bluuebunny/crossref_metadata_2025 huggingface dataset:
The CARA Network: Building Latin American Capacity in Hydrogeology and Water Resource Management
Authors: Bethune David N , Ryan M. Cathryn
Published: September 2010

Ground water supplies the vast majority of water supply in Central America yet, prior to the last 15 years, there have been only a handful of appropriately educated hydrogeologists in the region. The CARA Network (http://www.caragua.org) began in 1999 with the intention of building capacity in hydrogeology and water resource management in Central America. Capacity is built at national (public) universities through applied two‐year M.Sc. programs with related teaching and research. Each university is strengthened through the creation of new faculty positions, faculty training, the procurement of equipment/books/software, and the dedication of infrastructure. To date, the CARA M.Sc. programs have trained (or have in a current program) almost 160 Latin American hydrogeologists at the M.Sc. level. CARA short courses and workshops have trained over 2000 water‐sector professionals in the region in a variety of water themes related to groundwater and water resource management.
Using Classroom Assessment Techniques to Improve Foreign Language Composition Courses
Authors: Carduner Jessie
Published: September 2010

ABSTRACT: Classroom Assessment Techniques (CATs) are formative assessment tools that require, essentially, knowledge of one's discipline and a clear desire to increase student learning. CATs can assist instructors and students in setting realistic goals for a course and in shifting the focus of instruction from teaching to learning. Although the examples described in this article are from a Spanish grammar and composition course, the techniques presented may be adapted for use in nearly any second language course.
Learning Strategies and Achievement in the Spanish Writing Classroom: A Case Study
Authors: Olivares‐Cuhat Gabriela
Published: September 2010

ABSTRACT: This article investigates the effect of learning strategies on writing achievement in an intermediate‐advanced college‐level Spanish writing course, and examines the influence of the students native language and textbook on these strategies. The study was conducted with a class of 20 students that comprised nine first (L1) and eleven second/foreign (L2/FL) language speakers. The Strategy Inventory for Language Learning (SILL) provided an estimate of learning strategy use and two composition grades were used as a measure of the students' success. Additionally, the class was divided into two groups, each instructed to work with a different textbook. The following results were found: (1) on average, L1 students obtained higher grades than L2/FL students, (2) L1 students were more inclined to use affective and memory strategies than L2/FL students, and (3) use of memory strategies and writing achievement were significantly correlated, explaining 40% of the overall variability in grades. It was not possible to link the use of a specific textbook to the composition grades. Several classroom implications and suggestions for future research are discussed.
Fulminant type 1 diabetes mellitus associated with a reactivation of Epstein–Barr virus that developed in the course of chemotherapy of multiple myeloma
Authors: Fujiya Atsushi , Ochiai Hiroshi , Mizukoshi Toshihiro , Kiyota Atsushi , Shibata Taiga , Suzuki Atsushi , Ohashi Norimi , Sobajima Hiroshi
Published: September 2010

A 70‐year‐old woman who was diagnosed with multiple myeloma underwent chemotherapy. Three months after beginning chemotherapy, she was readmitted to the hospital because of fever and hepatopathy. Her elevated Epstein–Barr virus (EBV) antibody levels showed that the hepatopathy was caused by reactivation of EBV. On the 18th hospital day, the levels of fasting plasma glucose (FPG; 451 mg/dL) and pancreatic enzymes were suddenly elevated. Elevation of HbA1c level (6.4%) was slight, as compared with that of the FPG level. Arterial blood gas analysis showed metabolic acidosis and diabetic ketoacidosis was suspected. The serum C‐peptide level was below the detectable limit both before and after glucagon load, thereby suggesting an insulin‐dependent state. These features were identical to the features for fulminant type 1 diabetes mellitus. The levels of EBV anti‐viral capsid antigen immunoglobulin M decreased, and the clinical course was identical to that associated with reactivation of EBV infection. (J Diabetes Invest, doi: 10.1111/j.2040.1124.2010.00061.x, 2010)
Childhood development of common drive to a human leg muscle during ankle dorsiflexion and gait
Authors: Petersen Tue Hvass , Kliim‐Due Mette , Farmer Simon F. , Nielsen Jens Bo
Published: September 2010

Corticospinal drive has been shown to contribute significantly to the control of walking in adult human subjects. It is unknown to what extent functional change in this drive is important for maturation of gait in children. In adults, populations of motor units within a muscle show synchronized discharges during walking with pronounced coherence in the 15–50 Hz frequency band. This coherence has been shown to depend on cortical drive. Here, we investigated how this coherence changes with development. Forty‐four healthy children aged 4–15 years participated in the study. Electromyographic activity (EMG) was recorded from pairs of electrodes placed over the right tibialis anterior (TA) muscle during static dorsiflexion and during walking on a treadmill (speed from 1.8 to 4.8 km h−1). A significant increase of coherence with increasing age was found in the 30–45 Hz frequency band (gamma) during walking and during static ankle dorsiflexion. A significant correlation with age was also found in the 15–25 Hz frequency band (beta) during static foot dorsiflexion. χ2 analysis of differences of coherence between different age groups of children (4–6, 7–9, 10–12 and 13–15 years of age) revealed a significantly lower coherence in the gamma band for recordings during walking in children aged 4–6 years as compared to older children. Recordings during static dorsiflexion revealed significant differences in both the beta and gamma bands for children in the 4–6 and 7–9 years age groups as compared to the older age groups. A significant age‐related decrease in step‐to‐step variability of toe position during the swing phase of walking was observed. This reduction in the step‐to‐step variability of gait was correlated with increased gamma band coherence during walking. We argue that this may reflect an increased ability to precisely control the ankle joint position with age, which may be contingent on maturation of corticospinal control of the foot dorsiflexor muscles.
The Root of the Problem
Authors: Hines Pamela J.
Published: September 2010

Oscillations in gene expression define the positions of periodic lateral roots in a plant model.
Mosquito Malarial Memory
Authors: Ash Caroline
Published: September 2010

Early immune priming limits malaria parasite infection of mosquitoes.
National Multicenter Study of Predictors and Outcomes of Bacteremia upon Hospital Admission Caused by
Enterobacteriaceae
Producing Extended-Spectrum β-Lactamases
Authors: Marchaim Dror , Gottesman Tamar , Schwartz Orna , Korem Maya , Maor Yasmin , Rahav Galia , Karplus Rebekah , Lazarovitch Tsipora , Braun Eyal , Sprecher Hana , Lachish Tamar , Wiener-Well Yonit , Alon Danny , Chowers Michal , Ciobotaro Pnina , Bardenstein Rita , Paz Alona , Potasman Israel , Giladi Michael , Schechner Vered , Schwaber Mitchell J. , Klarfeld-Lidji Shiri , Carmeli Yehuda
Published: September 2010

Extended-spectrum β-lactamase (ESBL)-producing
Enterobacteriaceae
are pathogens that may lead to a spectrum of clinical syndromes. We aimed to identify predictors and outcomes of ESBL bacteremia upon hospital admission (UHA) in a nationwide prospective study. Thus, a multicenter prospective study was conducted in 10 Israeli hospitals. Adult patients with bacteremia due to
Enterobacteriaceae
diagnosed within 72 h of hospitalization were included. Patients with ESBL producers (cases) were compared to those with non-ESBL producers (controls), and a 1:1 ratio was attempted in each center. A case-control study to identify predictors and a cohort study to identify outcomes were conducted. Bivariate and multivariate logistic regressions were used for analyses. Overall, 447 patients with bacteremia due to
Enterobacteriaceae
were recruited: 205 cases and 242 controls. Independent predictors of ESBL were increased age, multiple comorbid conditions, poor functional status, recent contact with health care settings, invasive procedures, and prior receipt of antimicrobial therapy. In addition, patients presenting with septic shock and/or multiorgan failure were more likely to have ESBL infections. Patients with ESBL producers suffered more frequently from a delay in appropriate antimicrobial therapy (odds ratio [OR], 4.7;
P
, <0.001) and had a higher mortality rate (OR, 3.5;
P
, <0.001). After controlling for confounding variables, both ESBL production (OR, 2.3;
P
, 9.1) and a delay in adequate therapy (OR, 0.05;
P
, 0.001) were significant predictors for mortality and other adverse outcomes. We conclude that among patients with bacteremia due to
Enterobacteriaceae
UHA, those with ESBL producers tend to be older and chronically ill and to have a delay in effective therapy and severe adverse outcomes. Efforts should be directed to improving the detection of patients with ESBL bacteremia UHA and to providing immediate appropriate therapy.
OXA-134, a Naturally Occurring Carbapenem-Hydrolyzing Class D β-Lactamase from
Acinetobacter lwoffii
Authors: Figueiredo Samy , Poirel Laurent , Seifert Harald , Mugnier Pauline , Benhamou Dan , Nordmann Patrice
Published: September 2010

Acinetobacter lwoffii
, a species whose natural habitat is the human skin, intrinsically possesses a chromosomal gene encoding a carbapenem-hydrolyzing class D β-lactamase, OXA-134. This species may therefore constitute a reservoir for carbapenemase genes that may spread among other
Acinetobacter
species.
Comparative
In Vitro
Activities of Torezolid (DA-7157) against Clinical Isolates of Aerobic and Anaerobic Bacteria in South Korea
Authors: Yum Jong Hwa , Choi Sung Hak , Yong Dongeun , Chong Yunsop , Im Weon Bin , Rhee Dong-Kwon , Lee Kyungwon
Published: September 2010

Resistance of Gram-positive pathogens to first-line antimicrobial agents has been increasing in many parts of the world. We compared the
in vitro
activities of torezolid with those of other antimicrobial agents, including linezolid, against clinical isolates of major aerobic and anaerobic bacteria. Torezolid had an MIC
90
of ≤0.5 μg/ml for the Gram-positive bacterial isolates tested and was more potent than either linezolid or vancomycin.
Tafenoquine, an Antiplasmodial 8-Aminoquinoline, Targets
Leishmania
Respiratory Complex III and Induces Apoptosis
Authors: Carvalho Luis , Luque-Ortega Juan Román , Manzano José Ignacio , Castanys Santiago , Rivas Luis , Gamarro Francisco
Published: September 2010

Tafenoquine (TFQ), an 8-aminoquinoline analogue of primaquine, which is currently under clinical trial (phase IIb/III) for the treatment and prevention of malaria, may represent an alternative treatment for leishmaniasis. In this work, we have studied the mechanism of action of TFQ against
Leishmania
parasites. TFQ impaired the overall bioenergetic metabolism of
Leishmania
promastigotes, causing a rapid drop in intracellular ATP levels without affecting plasma membrane permeability. TFQ induced mitochondrial dysfunction through the inhibition of cytochrome
c
reductase (respiratory complex III) with a decrease in the oxygen consumption rate and depolarization of mitochondrial membrane potential. This was accompanied by ROS production, elevation of intracellular Ca

2+

levels and concomitant nuclear DNA fragmentation. We conclude that TFQ targets
Leishmania
mitochondria, leading to an apoptosis-like death process.
Antileishmanial and Antitrypanosomal Activities of the 8-Aminoquinoline Tafenoquine
Authors: Yardley Vanessa , Gamarro Francisco , Croft Simon L.
Published: September 2010

The 8-aminoquinoline tafenoquine showed significant
in vitro
activity against
Leishmania
species, including
L. donovani
amastigotes in macrophages, with 50% inhibitory concentrations (IC
50
s) between 0.1 and 4.0 μM for both pentavalent antimony (SbV)-sensitive and SbV-resistant strains and by oral administration in BALB/c mice, with 50% effective dose (ED
50
) values of 1.2 to 3.5 mg/kg for 5 days. Tafenoquine was less active against intracellular
Trypanosoma cruzi
amastigotes, with an IC
50
of 21.9 μM.
Role of Ferroportin in Macrophage-Mediated Immunity
Authors: Johnson Erin E. , Sandgren Andreas , Cherayil Bobby J. , Murray Megan , Wessling-Resnick Marianne
Published: September 2010

Perturbations in iron metabolism have been shown to dramatically impact host response to infection. The most common inherited iron overload disorder results from defects in the HFE gene product, a major histocompatibility complex class I-like protein that interacts with transferrin receptors. HFE-associated hemochromatosis is characterized by abnormally high levels of the iron efflux protein ferroportin. In this study, J774 murine macrophages overexpressing ferroportin were used to investigate the influence of iron metabolism on the release of nitric oxide (NO) in response to infection. Overexpression of ferroportin significantly impaired intracellular
Mycobacterium tuberculosis
growth during early stages of infection. When challenged with lipopolysaccharide (LPS) or
M. tuberculosis
infection, control macrophages increased NO synthesis, but macrophages overexpressing ferroportin had significantly impaired NO production in response to LPS or
M. tuberculosis
. Increased NO synthesis in control cells was accompanied by increased iNOS mRNA and protein, while upregulation of iNOS protein was markedly reduced when J744 cells overexpressing ferroportin were challenged with LPS or
M. tuberculosis
, thus limiting the bactericidal activity of these macrophages. The proinflammatory cytokine gamma interferon reversed the inhibitory effect of ferroportin overexpression on NO production. These results suggest a novel role for ferroportin in attenuating macrophage-mediated immune responses.
The Impact of Balsam Woolly Aphid Damage on Balsam Fir Stands in Newfoundland
Authors: Page G.
Published: September 2010

This paper presents data on the effects of balsam woolly aphid damage on the mensurational characteristics of balsam fir trees and stands, and quantitative estimates of changes in merchantable volumes that result from alterations in these characteristics. Average volume losses in damaged semi-mature and mature stands ranged from 2 to 6%, but were as high as 80% or more in a few highly susceptible stands. Strong and consistent relationships were recorded between the incidence and severity of aphid damage and a number of site and stand characteristics, including elevation, soil-moisture regime, stand height and age, balsam fir content and total balsam fir basal area of affected stands, and length of time damage had been present. These relationships were utilized to construct a hazard-rating system for use by forest managers in identifying sites and stands highly susceptible to severe damage, and in scheduling silvicultural control measures.
Magmatism in the southeastern Anatolian orogenic belt: transition from arc to post-collisional setting in an evolving orogen
Authors: Kuscu Ilkay , Kuscu Gonca Gencalioglu , Tosdal Richard M. , Ulrich Thomas D. , Friedman Richard
Published: September 2010

Late Cretaceous to Middle Eocene calc-alkaline to alkaline magmatic rocks emplaced within the southeastern Anatolian orogenic belt, the most extensive magmatic belt in Turkey, result from the complex collision between the Afro-Arabian and Eurasian plates and the subduction of the southern and northern Neotethyan oceanic basins beneath the Eurasian continental margin during the Alpine–Himalayan orogeny. In a transect in east-central Turkey extending from Baskil (Elazig) to Divrigi (Sivas) to the north, and from Copler (Erzincan) to Horozkoy (Nigde) to the SW, these magmatic rocks vary in time, spatial distribution, and composition.
40
Ar/
39
Ar ages supplemented by a few U–Pb ages geochronology from major plutons demonstrate a general younging of magmatism in the transect from
c
. 83 Ma in the south (Baskil) to
c
. 69 Ma in the north (Divrigi-Keban), followed by a
c
. 44 Ma scattered magmatic complex now found along a NE trending arcuate belt between Copler and Horoz. In general, trace element and rare earth element (REE) geochemistry in the magmatic rocks suggest two main sources for the melts: (1) a mantle-wedge and subducted oceanic lithosphere producing arc-type magma; and (2) metasomatized lithospheric mantle modified by subduction producing magmatic rocks with more metasomatized mantle and within plate signatures. The combination of geochemical and geochronological data presented herein provides a basis to reconstruct the temporal and spatial transition from subduction-related to post-collision and to late-orogenic magmatism in the eastern Mediterranean region. Subduction-related magmatism is rooted to closure of the Neo-Tethyan Ocean whereas post-collision and late orogenic-within plate-related magmatism is driven by the collision of a northern promontory of the SE Anatolian orogenic belt with northerly derived ophiolitic rocks. The magmatic transition occurs regionally in northerly to northwesterly trending belts in the southeastern Anatolian orogenic belt. The magmatism exhibit a clear shift from deep seated arc-type to late-orogenic from south (Baskil) to more deeply eroded mid-crustal plutons at the north (Divrigi), then to magmatism related to incipient slab-rupture from northeast (Copler, Kabatas, Bizmisen-Calti) to SW (Karamadazi and Horoz). The age progression follows a south-to-north geochemical trend of decreasing crustal input into mantle-derived magmas, and is explained as a consequence of slab roll-back after the collision/obduction of northerly ophiolites followed by slab steepening and incipient rupture leading to transtensional block faulting and subsidence, and thus to the preservation of near-surface magmatic products along a NE trending belt.
Seismic images of crustal variations beneath the East Anatolian Plateau (Turkey) from teleseismic receiver functions
Authors: Özacar A. Arda , Zandt George , Gilbert Hersh , Beck Susan L.
Published: September 2010

We used teleseismic P-wave receiver functions recorded by the Eastern Turkey Seismic Experiment to determine the crustal structure across an active continent–continent collision zone. Moho depth and
V
p
/
V
s
variations in the region are mapped by incorporating crustal multiples and later two-dimsional (2-D) seismic profiles are produced using a common conversion point technique with our crustal
V
p
/
V
s
estimates. Moho depths do not correlate with surface topography and reveal a relatively thin crust consistent with the high plateau being supported by hot asthenosphere near the base of the crust. Under the Arabian plate, the crust is thinnest (
c
. 35 km) and exhibits high
V
p
/
V
s
(≥1.8) associated with mafic compositions. In the east, the crust gradually becomes thicker towards the north and exceeds 45 km in the northeastern side whereas in the west, the crust thickens sharply near the Bitlis suture and displays pronounced Moho topography within the Anatolian plate that suggests the presence of multiple fragments.
V
p
/
V
s
variations show an anomalously high
V
p
/
V
s
corridor (≥1.85) along the North Anatolian Fault and near the youngest volcanic units (
c
. 3 Ma) and support the presence of partial melt. This corridor is spatially limited from both north and south by low
V
p
/
V
s
regions implying a change in crustal composition. Near the Bitlis suture, a layered
V
p
/
V
s
model points to the source of low
V
p
/
V
s
in the lower crust that may be rich in quartz. Furthermore, the seismic profiles indicate a prominent low velocity zone in the lower crust across a large area beneath the plateau that may act as a decoupling zone between the crust and upper mantle.
The crustal structure of the Black Sea from the reinterpretation of deep seismic sounding data acquired in the 1960s
Authors: Yegorova Tamara , Baranova Ekaterina , Omelchenko Viktor
Published: September 2010

A ray-tracing modelling of seismic refraction data acquired in the 1960s has been undertaken on two north–south lines – Profile 25 in the western part of the Black Sea and Profile 28/29 crossing the Azov Sea and central part of the Black Sea. The velocity model along Profile 25 shows two domains interpreted as thin (5 km) high-velocity (sub-)oceanic crust below the deep-water part of the Western Black Sea (WBS) basin, covered by 12–13 km of Cretaceous and younger sediments, and a 39 km thick continental domain of the Scythian Platform and southernmost part of the East European Platform. They are separated by a high-amplitude normal fault, interpreted as being related to the opening of the WBS during Late Cretaceous rifting. The velocity model on Profile 28/29 shows what is interpreted as oceanic crust on the northwestern extremity of the Eastern Black Sea Basin (EBS) and thinned continental crust (Moho depths at 29 km) underlying the mid-Black Sea Ridge (MBSR) that separates the EBS and WBS. The basement of the MBSR comprises three units, which in an en echelon-like manner elevate southwards from a depth of 10–11 km beneath the Andrusov Ridge to 6 km on Arkhangelsky Ridge. An inclined seismic boundary at the Moho interface may be related to oblique rifting setting during the initial formation of the EBS.
Brittle deformation, palaeostress field reconstruction and tectonic evolution of the Eastern Balkanides (Bulgaria) during Mesozoic and Cenozoic times
Authors: Bergerat F. , Vangelov D. , Dimov D.
Published: September 2010

Brittle tectonics analysis and stress tensor reconstructions allow us to better depict the Mesozoic and Cenozoic geodynamical evolution of the Eastern Balkanides which is characterized by a series of overimposed basin-systems. The Late Permian–Triassic corresponds to a wide carbonate platform with local embryonic troughs. During the Jurassic–Early Cretaceous period, the area, limited by regional unconformities, was at first dominated by the existence of a deep basin until the latest middle Jurassic, then by its gradual closure during the Late Jurassic–Early Cretaceous. Traces of these tectonic events are found as a result of brittle tectonic data analysis, especially in the Strandja Zone where NE–SW extension and ENE–WSW compression may be related to the Early Alpine phases of rifting and shortening, respectively. The Late Cretaceous–middle Eocene period was governed by the back-arc basin/island-arc system of East Balkan/Srednogorie zones. The inversion of these extensional zones occurred after the Maastrichtian, then important shearing and thrusting developed during the major shortening in the latest Middle Eocene. These Late Alpine tectonic phases were well characterized by brittle tectonics and the analysis of faulting in terms of stress tensors allows us to identify the main directions of extension of the rifting stage which is north–south to NNE–SSW, and the directions of compression of the Laramian and Illyrian phases, which are NE–SW and north–south, respectively. The relationships between folding and reverse and strike–slip faults are established as well as the occurrence of post-folding normal faults assigned to collapse process following the shortening.
Dating of the Black Sea Basin: new nannoplankton ages from its inverted margin in the Central Pontides (Turkey)
Authors: Hippolyte J.-C. , Müller C. , Kaymakci N. , Sangu E.
Published: September 2010

The Eocene uplift and inversion of a part of the Black Sea margin in the Central Pontides, allows us to study the stratigraphic sequence of the Western Black Sea Basin (WBS). The revision of this sequence, with 164 nannoplankton ages, indicates that subsidence and rifting started in the Upper Barremian and accelerated during the Aptian. The rifting of the western Black Sea Basin lasted about 40 Ma (from late Barremian to Coniacian). In the inner, inverted, Black Sea margin, the syn-rift sequence ends up with shallow marine sands. The uppermost Albian to Turonian was a period of erosion or non deposition. This regional mid-Cretaceous stratigraphical gap might result from rift flank uplift, as expected in the case of a thick and cold pre-rift lithosphere. However, coeval collision of the Kargi Block, along the North Tethyan subduction zone at the southern margin of the Pontides, might also have contributed to this uplift. A rapid thermal post-rift subsidence of the margin occurred during the Coniacian–Santonian. Collision of the Kirşehir continental block commenced in Early Eocene time (zone NP12) giving rise to compressional deformation and sedimentation in piggyback basins in the Central Pontides, whereas the eastern Black Sea was still opening.
Detection of reactive jamming in sensor networks
Authors: Strasser Mario , Danev Boris , Čapkun Srdjan
Published: September 2010

An integral part of most security- and safety-critical applications is a dependable and timely alarm notification. However, owing to the resource constraints of wireless sensor nodes (i.e., their limited power and spectral diversity), ensuring a timely and jamming-resistant delivery of alarm messages in applications that rely on wireless sensor networks is a challenging task. With current alarm forwarding schemes, blocking of an alarm by jamming is straightforward and jamming is very likely to remain unnoticed. In this work, we propose a novel jamming detection scheme as a solution to this problem. Our scheme is able to identify the cause of bit errors for individual packets by looking at the received signal strength during the reception of these bits and is well-suited for the protection of reactive alarm systems with very low network traffic. We present three different techniques for the identification of bit errors based on: predetermined knowledge, error correcting codes, and limited node wiring. We perform a detailed evaluation of the proposed solution and validate our findings experimentally with Chipcon CC1000 radios. The results show that our solution effectively detects sophisticated jamming attacks that cannot be detected with existing techniques and enables the formation of robust sensor networks for dependable delivery of alarm notifications. Our scheme also meets the high demands on the energy efficiency of reactive surveillance applications as it can operate without introducing additional wireless network traffic.
Degrees, Distance, and Dollars
Authors: Krakovsky Marina
Published: September 2010

Demand for higher education continues to rise at double-digit rates, boosting the number of students taking one or more online courses in the U.S. in the fall of 2008 to 2.4 million. Yet while elite schools are reaching the masses as a philanthropic gesture, they tend to avoid granting more degrees. Writer Marina Krakovsky investigates this trend in an article that originally appeared in Communications of the ACM. (Both Communications and eLearn Magazine are owned and operated by the ACM, a non-profit membership organization.)
Supersonic e-Learning
Authors: Little Bob
Published: September 2010

Learning technologists have stated innumerable times that delivery technology is irrelevant. What really matters is that the learning materials are designed and developed in line with accepted best practice in instructional design whichever formula that happens to be at the time. Yet, as soon as that statement is made, everyone becomes sidetracked by the latest piece of learning delivery technology. Do delivery technologies indeed matter, or is content really still king in e-learning?
Toll-Like Receptors, Tissue Injury, and Tumourigenesis
Authors: Ioannou Savvas , Voulgarelis Michael
Published: September 2010

Toll-like receptors (TLRs) belong to a class of molecules known as pattern recognition receptors, and they are part of the innate immune system, although they modulate mechanisms that impact the development of adaptive immune responses. Several studies have shown that TLRs, and their intracellular signalling components, constitute an important cellular pathway mediating the inflammatory process. Moreover, their critical role in the regulation of tissue injury and wound healing process as well as in the regulation of apoptosis is well established. However, interest in the role of these receptors in cancer development and progression has been increasing over the last years. TLRs are likely candidates to mediate effects of the innate immune system within the tumour microenvironment. A rapidly expanding area of research regarding the expression and function of TLRs in cancer cells and its association with chemoresistance and tumourigenesis, and TLR-based therapy as potential immunotherapy in cancer treatment is taking place over the last years.
Vitamin A Deficiency after Gastric Bypass Surgery: An Underreported Postoperative Complication
Authors: Zalesin Kerstyn C. , Miller Wendy M. , Franklin Barry , Mudugal Dharani , Rao Buragadda Avdesh , Boura Judith , Nori-Janosz Katherine , Chengelis David L. , Krause Kevin R. , McCullough Peter A.
Published: September 2010

Introduction. Few data are available on vitamin A deficiency in the gastric bypass population.Methods. We performed a retrospective chart review of gastric bypass patients (n=69, 74% female). The relationship between serum vitamin A concentration and markers of protein metabolism at 6-weeks and 1-year post-operative were assessed.Results. The average weight loss at 6-weeks and 1-year following surgery was20.1±9.1 kg and44.1±17.1 kg, respectively. At 6 weeks and 1 year after surgery, 35% and 18% of patients were vitamin A deficient, (<325 mcg/L). Similarly, 34% and 19% had low pre-albumin levels (<18 mg/dL), at these time intervals. Vitamin A directly correlated with pre-albumin levels at 6 weeks (r=0.67,P<0.001) and 1-year (r=0.67,  P<0.0001). There was no correlation between the roux limb length measurement and pre-albumin or vitamin A serum concentrations at these post-operative follow-ups. Vitamin A levels and markers of liver function testing were also unrelated.Conclusion. Vitamin A deficiency is common after bariatric surgery and is associated with a low serum concentration of pre-albumin. This fat-soluble vitamin should be measured in patients who have undergone gastric bypass surgery and deficiency should be suspected in those with evidence of protein-calorie malnutrition.
EphB4 Promotes Site-Specific Metastatic Tumor Cell Dissemination by Interacting with Endothelial Cell–Expressed EphrinB2
Authors: Héroult Mélanie , Schaffner Florence , Pfaff Dennis , Prahst Claudia , Kirmse Robert , Kutschera Simone , Riedel Maria , Ludwig Thomas , Vajkoczy Peter , Graeser Ralph , Augustin Hellmut G.
Published: September 2010

The tyrosine kinase receptor EphB4 interacts with its ephrinB2 ligand to act as a bidirectional signaling system that mediates adhesion, migration, and guidance by controlling attractive and repulsive activities. Recent findings have shown that hematopoietic cells expressing EphB4 exert adhesive functions towards endothelial cells expressing ephrinB2. We therefore hypothesized that EphB4/ephrinB2 interactions may be involved in the preferential adhesion of EphB4-expressing tumor cells to ephrinB2-expressing endothelial cells. Screening of a panel of human tumor cell lines identified EphB4 expression in nearly all analyzed tumor cell lines. Human A375 melanoma cells engineered to express either full-length EphB4 or truncated EphB4 variants which lack the cytoplasmic catalytic domain (ΔC-EphB4) adhered preferentially to ephrinB2-expressing endothelial cells. Force spectroscopy by atomic force microscopy confirmed, on the single cell level, the rapid and direct adhesive interaction between EphB4 and ephrinB2. Tumor cell trafficking experiments in vivo using sensitive luciferase detection techniques revealed significantly more EphB4-expressing A375 cells but not ΔC-EphB4–expressing or mock-transduced control cells in the lungs, the liver, and the kidneys. Correspondingly, ephrinB2 expression was detected in the microvessels of these organs. The specificity of the EphB4-mediated tumor homing phenotype was validated by blocking the EphB4/ephrinB2 interaction with soluble EphB4-Fc. Taken together, these experiments identify adhesive EphB4/ephrinB2 interactions between tumor cells and endothelial cells as a mechanism for the site-specific metastatic dissemination of tumor cells. Mol Cancer Res; 8(10); 1297–309. ©2010 AACR.
CYP4A2-Induced Hypertension Is 20-Hydroxyeicosatetraenoic Acid– and Angiotensin II–Dependent
Authors: Sodhi Komal , Wu Cheng-Chia , Cheng Jennifer , Gotlinger Katherine , Inoue Kazuyoshi , Goli Mohan , Falck John R. , Abraham Nader G. , Schwartzman Michal L.
Published: September 2010

We have shown previously that increased vascular endothelial expression of CYP4A2 leads to 20-hydroxyeicosatetraenoic (20-HETE)–dependent hypertension. The renin-angiotensin system is a key regulator of blood pressure. In this study, we examined possible interactions between 20-HETE and the renin-angiotensin system. In normotensive (110±3 mm Hg) Sprague-Dawley rats transduced with a lentivirus expressing the CYP4A2 cDNA under the control of an endothelial-specific promoter (VECAD-4A2), systolic blood pressure increased rapidly, reaching 139±1, 145±3, and 150±2 mm Hg at 3, 5, and 10 days after transduction; blood pressure remained elevated, thereafter, with maximum levels of 163±3 mm Hg. Treatment with lisinopril, losartan, or the 20-HETE antagonist 20-hydroxyeicosa-6(Z), 15(Z)-dienoic acid decreased blood pressure to control values, but blood pressure returned to its high levels after cessation of treatment. Endothelial-specific overexpression of CYP4A2 resulted in increased expression of vascular angiotensin-converting enzyme (ACE) and angiotensin II type 1 receptor and increased levels of plasma and tissue angiotensin II; all were attenuated by treatment with HET0016, an inhibitor of 20-HETE synthesis, or with 20-hydroxyeicosa-6(Z), 15(Z)-dienoic acid. In cultured endothelial cells, 20-HETE specifically and potently induced ACE expression without altering the expression of ACE2, angiotensinogen, or angiotensin II receptors. This is the first study to demonstrate that 20-HETE, a key constrictor eicosanoid in the microcirculation, induces ACE and angiotensin II type 1 receptor expression and increases angiotensin II levels, suggesting that the mechanisms by which 20-HETE promotes hypertension include activation of the renin-angiotensin system that is likely initiated at the level of ACE induction.
Comparative Efficacy of Yohimbine Against Pyridostigmine for the Treatment of Orthostatic Hypotension in Autonomic Failure
Authors: Shibao Cyndya , Okamoto Luis E. , Gamboa Alfredo , Yu Chang , Diedrich Andre' , Raj Satish R. , Robertson David , Biaggioni Italo
Published: September 2010

Orthostatic hypotension affects patients with autonomic failure producing considerable disability because of presyncopal symptoms. Severely affected patients may have residual sympathetic tone that can be engaged to increase blood pressure (BP) with the α-2 adrenergic antagonist yohimbine. This medication activates sympathetic outflow centrally and unrestrains norepinephrine release from noradrenergic neurons. Alternatively, the acetylcholinesterase inhibitor, pyridostigmine, can increase sympathetic tone by improving ganglionic cholinergic neurotransmission. Our purpose was to compare these complementary approaches and to explore whether the combination would lead to synergistic increases in BP. We compared the effects of 60 mg of pyridostigmine and 5.4 mg of yohimbine in a single-blind, randomized, placebo-controlled, crossover fashion. In a subset of patients we tested the combination of pyridostigmine and yohimbine. Our primary outcome was the change in standing diastolic BP 60 minutes after drug administration from baseline. We studied a total of 31 patients with severe autonomic failure. Yohimbine significantly improved standing diastolic BP as compared with placebo (11±3 mm Hg [95% CI: 6 to 16 mm Hg];
P
<0.001). On the contrary, pyridostigmine did not increase the standing diastolic BP (0.6±3 mm Hg [95% CI: −5 to 5 mm Hg];
P
=0.823). Only yohimbine showed a significant improvement in presyncopal symptoms. Sixteen patients received the combination of pyridostigmine and yohimbine, but no evidence of synergistic pressor effect was found. Engaging residual sympathetic tone with yohimbine is a more effective approach to improve orthostatic hypotension as compared with pyridostigmine in patients with severe orthostatic hypotension.
Robust Early Pregnancy Prediction of Later Preeclampsia Using Metabolomic Biomarkers
Authors: Kenny Louise C. , Broadhurst David I. , Dunn Warwick , Brown Marie , North Robyn A. , McCowan Lesley , Roberts Claire , Cooper Garth J.S. , Kell Douglas B. , Baker Philip N.
Published: September 2010

Preeclampsia is a pregnancy-specific syndrome that causes substantial maternal and fetal morbidity and mortality. The etiology is incompletely understood, and there is no clinically useful screening test. Current metabolomic technologies have allowed the establishment of metabolic signatures of preeclampsia in early pregnancy. Here, a 2-phase discovery/validation metabolic profiling study was performed. In the discovery phase, a nested case-control study was designed, using samples obtained at 15±1 weeks’ gestation from 60 women who subsequently developed preeclampsia and 60 controls taking part in the prospective Screening for Pregnancy Endpoints cohort study. Controls were proportionally population matched for age, ethnicity, and body mass index at booking. Plasma samples were analyzed using ultra performance liquid chromatography-mass spectrometry. A multivariate predictive model combining 14 metabolites gave an odds ratio for developing preeclampsia of 36 (95% CI: 12 to 108), with an area under the receiver operator characteristic curve of 0.94. These findings were then validated using an independent case-control study on plasma obtained at 15±1 weeks from 39 women who subsequently developed preeclampsia and 40 similarly matched controls from a participating center in a different country. The same 14 metabolites produced an odds ratio of 23 (95% CI: 7 to 73) with an area under receiver operator characteristic curve of 0.92. The finding of a consistent discriminatory metabolite signature in early pregnancy plasma preceding the onset of preeclampsia offers insight into disease pathogenesis and offers the tantalizing promise of a robust presymptomatic screening test.
Simulated Sea Surface Salinity Variability in the Tropical Indian Ocean
Authors: Sharma Rashmi , Agarwal Neeraj , Momin Imran M. , Basu Sujit , Agarwal Vijay K.
Published: September 2010

A long-period (15 yr) simulation of sea surface salinity (SSS) obtained from a hindcast run of an ocean general circulation model (OGCM) forced by the NCEP–NCAR daily reanalysis product is analyzed in the tropical Indian Ocean (TIO). The objective of the study is twofold: assess the capability of the model to provide realistic simulations of SSS and characterize the SSS variability in view of upcoming satellite salinity missions. Model fields are evaluated in terms of mean, standard deviation, and characteristic temporal scales of SSS variability. Results show that the standard deviations range from 0.2 to 1.5 psu, with larger values in regions with strong seasonal transitions of surface currents (south of India) and along the coast in the Bay of Bengal (strong Kelvin-wave-induced currents). Comparison of simulated SSS with collocated SSS measurements from the National Oceanographic Data Center and Argo floats resulted in a high correlation of 0.85 and a root-mean-square error (RMSE) of 0.4 psu. The correlations are quite high (>0.75) up to a depth of 300 m. Daily simulations of SSS compare well with a Research Moored Array for African–Asian–Australian Monsoon Analysis and Prediction (RAMA) buoy in the eastern equatorial Indian Ocean (1.5°S, 90°E) with an RMSE of 0.3 psu and a correlation better than 0.6. Model SSS compares well with observations at all time scales (intraseasonal, seasonal, and interannual). The decorrelation scales computed from model and buoy SSS suggest that the proposed 10-day sampling of future salinity sensors would be able to resolve much of the salinity variability at time scales longer than intraseasonal. This inference is significant in view of satellite salinity sensors, such as Soil Moisture and Ocean Salinity (SMOS) and Aquarius.
The Impact of a Hemispheric Circulation Regime on Fall Precipitation over North America
Authors: Small David , Islam Shafiqul , Barlow Mathew
Published: September 2010

While there is growing evidence that the main contribution to trends in U.S. precipitation occurs during fall, most studies of seasonal precipitation have focused on winter or summer. Here, the leading mode of fall precipitation variability over North America is isolated from multiple data sources and connected to a hemispheric-scale circulation pattern. Over North America, the leading mode of fall precipitation variability in both station-based and satellite-blended data is a tripole that links fall precipitation anomalies in southern Alaska, the central United States, and eastern Canada. This mode is part of a larger pattern of alternating wet and dry anomalies stretching from the western Pacific to the North Atlantic. Dynamically, the precipitation anomalies are closely associated with changes to regional-scale moisture transport that are, in turn, linked to two independently identified hemispheric-scale wave patterns that are one-quarter wavelength out of phase (i.e., in quadrature) and resemble the circumglobal teleconnection.
Hypertriglyceridemia in a Pediatric Referral Practice: Experience With 300 Patients
Authors: de Ferranti Sarah D. , Crean Sheila , Cotter Jill , Boyd Dylan , Osganian Stavroula K.
Published: September 2010

Background: Pediatric hypertriglyceridemia is an emerging comorbidity of childhood obesity. Methods: This study reviewed medical records retrospectively to describe the characteristics and clinical course of 300 at-risk children followed in a pediatric preventive cardiology clinic. Results: Average baseline triglyceride (TG) level was 269 mg/dL (SD 342 mg/dL); 91% had TG levels between 150 and 399 mg/dL. A total of 77% were overweight/obese, 23% had elevated blood pressure, 23% had a family history of high triglycerides, and 11% reported a psychiatric diagnosis (33.3% of those with severe TG elevations). Diet and activity change were the first-line therapies; few were taking lipid-lowering medications (baseline, 5.1%; follow-up, 11.4%). TG levels declined by 23% (average, 88 mg/dL; SD 231), often with a decline or plateau in TG risk category. Children with a lower body mass index (<85% gender- and age-matched percentile) were more likely to improve in TG category than heavier children (70% vs 40%; P ≤ .05).
Patient—Provider Communication and Human Papillomavirus Vaccine Acceptance
Authors: Rand Cynthia M. , Schaffer Stanley J. , Humiston Sharon G. , Albertin Christina S. , Shone Laura P. , Heintz Eric V. , Blumkin Aaron K. , Stokley Shannon , Szilagyi Peter G.
Published: September 2010

The authors performed telephone interviews of parents of adolescents (n = 430) and their older adolescents (n = 208) in Monroe County, New York to measure parent and adolescent acceptance of human papillomavirus (HPV) vaccine, its association with ratings of provider communication, and vaccine-related topics discussed with the adolescent’s provider. More than half of adolescent girls had already received an HPV vaccination, with fewer than one quarter refusing. Parent and teen ratings of provider communication was high, and not related to HPV vaccine refusal. Parents were more likely to refuse if they were Hispanic (odds ratio [OR] = 5.88, P = .05) or did not consider vaccines “very safe” (OR = 2.76, P = .04). Most parents of boys (85%) believed males should be given HPV vaccine if recommended. Few parents and teens recalled discussing that vaccination does not preclude future Pap smear testing. Providers should address cultural and vaccine safety concerns in discussions about HPV vaccine.
Organizational Culture and Its Impact on Partnering Between Community Agencies and Postsecondary Institutions to Help Low-Income Students Attend College
Authors: Kezar Adrianna
Published: September 2010

Given the importance of postsecondary institutions partnering with community agencies and groups to meet a variety of essential goals such as access and success of students, this study investigated one such partnership with the aim of attempting to understand the experience of community-led partnerships and the role of culture in partnerships between community agencies and postsecondary institutions. Although the collaboration literature often assumes similarities among nonprofit organizations, this study identified a host of differences that need to be carefully negotiated and worked through while developing a partnering. Knowledge about the areas of culture differences serves as a guide for forming and developing relationships between postsecondary institutions and community agencies that further the goals of urban educators.
Developing a Transformative School Vision: Lessons From Peer-Nominated Principals
Authors: Kose Brad W.
Published: September 2010

Scholars argue or imply that schools should build transformative school visions that promote equity, diversity, and social justice. However, little empirical research has investigated the principal’s role in this endeavor or analyzed the practical dimensions of transformative vision statements. This study re-examined relevant data from two qualitative studies of school principals who were peer-nominated for exemplary transformative practices. The findings delineate principals’ practices in developing a transformative vision and suggest several useful dimensions of transformative vision statements. Implications for practice and research are discussed.
Intradistrict Resource Allocation: Key Findings and Policy Implications
Authors: Houck Eric A.
Published: September 2010

The focus on school-level performance brought about by the No Child Left Behind Act—as well as recent court cases challenging the use of race in student assignment polices—has brought greater attention to the need to for careful study of the allocation of resources within school districts. This paper describes the policy context, review key intradistrict studies, and proffers three extensions to the field of intradistrict resource analysis: consideration of teacher labor markets, consideration of the resource implications of peer effects, and the use of additional statistical methods such as quantile regression. Taken together, these topics have the promise to extend the field of intradsitrict resource allocation.
Citizenship Literacy Among 16-Year Old Secondary School Students in Malaysia
Authors: Fatt Hee Tie  , Yan Piaw Chua
Published: September 2010

The purpose of this study is to investigate the citizenship literacy of secondary school students in Malaysia. Citizenship literacy was examined from two perspectives, namely, the level of knowledge; and secondly, the perception of selected aspects of citizenship. A questionnaire was developed to elicit the response of the subjects. A total of 4,040 sixteen year old secondary school students participated in the study. The Crammer’s V Correlation Coefficient was used to analyze the relationship between citizenship literacy and the selected variables. A similar analysis was conducted to determine the relationship between the perceptions of the subjects and the variables.