bluuebunny/crossref_metadata_2025 huggingface dataset:
Soil Organic Matter Processes in Old‐Growth Redwood Forest Canopies
Authors: Enloe Heather A. , Quideau Sylvie A. , Graham Robert C. , Sillett Stephen C. , Oh S.-W. , Wasylishen R. E.
Published: January 2010

Organic soils up to 1 m thick cover tree surfaces within the canopies of old‐growth redwood [Sequoia sempervirens (D. Don) Endl.] forests 50 m or more above the ground. Very little is known about litter quality and litter decomposition processes within these canopies. A combination of solid‐state cross‐polarization magic‐angle spinning 13C nuclear magnetic resonance (NMR) spectroscopy, natural 13C and 15N isotopic analyses, and proximate analyses were used to gain insight into soil organic matter accumulation and decay processes within two arboreal soils. Arboreal soil, redwood, and fern (Polypodium scouleri Hook. & Grev.) litter as well as epiphyte roots were analyzed. Proximate analyses showed that the arboreal soil parent materials contained a high concentration of the acid residue fraction (i.e., Klason lignin), from 379 g kg−1 for fern rhizomes up to 652 g kg−1 for redwood bark litter. This high concentration of acid residue fraction in the soil parent materials probably promotes organic matter accumulation within the tree crown. Results from 13C NMR spectroscopy analyses indicated a preferential decomposition of carbohydrates and an accumulation of alkyl structures from the redwood and fern litter to the <2‐mm soil materials and from the Oi to the Oa horizons in both soils. On the other hand, there was no consistent variation in terms of C/N ratios and stable isotope composition along the depth gradient, suggesting that organic matter in these soils has undergone limited microbial processing but instead reflects the selective preservation of recalcitrant litter moieties.
Evidence for Carbon Saturation in a Highly Structured and Organic‐Matter‐Rich Soil
Authors: Chung Haegeun , Ngo Kathie J. , Plante Alain , Six Johan
Published: January 2010

Recent studies suggest that mineral soils of temperate ecosystems have a limit in C sequestration capacity, and we reasoned that C saturation will be most evident in soils that are already rich in soil organic C (SOC) and have been exposed to a broad range of C inputs. Therefore, we determined soil C saturation in an agricultural experiment located in Ellerslie, AB, Canada, where organic‐matter‐rich soils have been cropped to cereal grain for 25 yr. In this experiment, the soils were subject to a broad range of soil C inputs due to a combination of straw retention, tillage, and N fertilization treatments. We determined if C saturation is occurring in soil size fractions that are functionally different. Soils were highly aggregated, with >85% of the soils consisting of macroaggregates. Straw retention, tillage, and N fertilization had no significant effect on the SOC concentration of most soil fractions. Soil organic C concentration of whole soil and soil aggregates isolated from whole soil did not increase with greater soil C inputs. Most of the soil fractions within the large or small macroaggregates did not sequester additional SOC in response to higher soil C inputs. Conversely, SOC concentration in experimental plot soils was significantly lower than that of adjacent grassland soils, which suggests that the maximum C sequestration level for a specific soil type depends on the management practices used. We conclude that C sequestration is governed by C saturation in this highly structured and high‐C soil. Our study suggests that soils of temperate ecosystems that are closer to their C saturation capacity may store additional C less effectively than soils that are further away from their saturation capacity.
Runoff Nitrogen Loss with Simulated Rainfall Immediately Following Poultry Manure Application for Corn Production
Authors: Diaz D. A. Ruiz , Sawyer J. E. , Barker D. W. , Mallarino A. P.
Published: January 2010

Nitrogen loss from a soybean [Glycine max (L.) Merr.]–corn (Zea mays L.) rotation by runoff to surface water can be significant. This study was conducted to determine short‐term N loss in runoff immediately after poultry manure application and assess the effects of manure rate and incorporation on losses. The study was conducted for 3 yr at nine Iowa fields previously cropped to soybean. Poultry manure sources were applied in the fall or spring to untilled soybean stubble at intended rates of 0, 84, and 168 kg total N ha−1with three replications. Within 2 d of application, simulated rainfall was applied to 3‐m2 areas to provide a single 30‐min runoff event. The total Kjeldahl N (TKN) and NH4+–N concentration and load in runoff increased with higher manure rates, with the associated manure TKN and NH4+–N correlated with runoff losses. With the high manure rate, runoff TKN and NH4+–N concentration averaged 33 and 15 mg L−1 and the TKN and NH4+–N load 2.6 and 1.1 kg ha−1, respectively. Runoff concentration and load of TKN and NH4+–N was significantly decreased with incorporation, approximately 50% and 90%, respectively. Tillage increased TKN in runoff when no manure was applied, but loses were lower than the treatment with manure and incorporation. The NO3−–N load in runoff was low and not affected by manure application. The results show that rainfall shortly after surface application of poultry manure can result in increased runoff TKN and NH4+–N, with loss related to manure rate, specific N fraction, and incorporation, which significantly reduced manure N in surface runoff.
Unsaturated Hydraulic Conductivity Estimation of a Forest Soil Assuming a Stochastic‐Convective Process
Authors: Homolák Marián , Pichler Viliam , Jury William A. , Capuliak Jozef , O'Linger JoAnn , Gregor Juraj
Published: January 2010

Measurement of soil hydraulic conductivity requires considerable time and effort, which makes it difficult to characterize this important parameter across larger areas, especially remote forest regions. Forest soils are frequently texturally coarser than those in agricultural areas, making them more probable candidates for applications building on the stochastic‐convective hypothesis. We developed a method for measuring unsaturated soil hydraulic conductivity based on the analysis of a dye tracer resident concentration profile. In the experiment, partially saturated, steady‐state water flow was established in a forest allophanic soil by a sprinkler operating at 50 mm h−1, after which the water application was switched to a 10 mg L−1 Brilliant Blue FCF solution. The tracer was applied continuously until its cumulative infiltration reached 125 mm, after which the stained soil profile was exposed and photographed. The picture was subjected to an image analysis procedure designed to obtain the resident concentration profile of the tracer. The concentration was fitted to the solution of the convective lognormal transfer function, whose parameters were used in further calculations using functional relationships derived from the stochastic‐convective framework. The resulting hydraulic conductivity as a function of soil water content agreed within an order of magnitude with the relationship obtained by the instantaneous profile method. While the Mualem–van Genuchten model better reproduced the shape of that relationship, it strongly underestimated the hydraulic conductivity across the soil water content interval of interest (0.1–0.4). Finally, ways to improve the predictive capacity of the stochastic‐convective approach in terms of the general trends of the functional relationship were proposed.
Grandparent-Grandchild Relationships: From Families in Contexts to Families as Contexts
Authors: Davey Adam , Savla Jyoti , Janke Megan , Anderson Shayne
Published: January 2010

Relationships between grandparents and grandchildren provide an excellent framework for integrating family theory and family methodology. Systematic differences as a function of age, gender, life expectancy, and health as played out through generations suggest some topics are best studied by disentangling variability between and within families. Using data from 1,345 grandchildren (52% girls, mean age 13.69 years, range 9 to 20) reporting on 3,664 grandparents, we compare results obtained from studying grandparent-grandchild relationships individually and at the family level. Results suggest important predictors of relationship quality at the within-subject and between-subject levels. Future research should more carefully integrate each level into theory and design.
Isoflavonoids — an overview of their biological activities and potential health benefits
Authors: Miadoková Eva
Published: January 2010

Isoflavonoids — an overview of their biological activities and potential health benefits

There are many biological activities attributed to isoflavonoids. The majority of them could be beneficial and some of them may be detrimental, depending on specific circumstances. Isoflavonoids play an important role in human nutrition as health promoting natural chemicals. They belong to plant secondary metabolites that mediate diverse biological functions through numerous pathways. They are structurally similar to estrogens, exerting both estrogenic and antiestrogenic properties in various tissues. The results of epidemiologic studies exploring the role of isoflavonoids in human health have been inconclusive. Some studies support the notion of a protective effect of their consumption in immunomodulation, cognition, risk reduction of certain cancers, cardiovascular and skin diseases, osteoporosis and obesity, as well as relief of menopausal symptoms. Other studies failed to demonstrate any effects.
Physical Therapy in the Emergency Department: Development of a Novel Practice Venue
Authors: Fleming-McDonnell Debra , Czuppon Sylvia , Deusinger Susan S. , Deusinger Robert H.
Published: January 2010

Background and Purpose

The American Physical Therapy Association's Vision 2020 advocates that physical therapists be integral members of health care teams responsible for diagnosing and managing movement and functional disorders. This report details the design and early implementation of a physical therapist service in the emergency department (ED) of a large, urban hospital and presents recommendations for assessing the effectiveness of physical therapists in this setting.

Case Description

Emergency departments serve multiple purposes in the American health care system, including care of patients with non–life-threatening illnesses. Physical therapists have expertise in screening for problems that are not amenable to physical therapy and in addressing a wide range of acute and chronic musculoskeletal pain problems. This expertise invites inclusion into the culture of ED practice. This administrative case report describes planning and early implementation of a physical therapist practice in an ED, shares preliminary outcomes, and provides suggestions for expansion and effectiveness testing of practice in this novel venue.

Outcomes

Referrals have increased and length of stay has decreased for patients receiving physical therapy. Preliminary surveys suggest high patient and practitioner satisfaction with physical therapy services. Outpatient physical therapy follow-up options were developed. Educating ED personnel to triage patients who show deficits in pain and functional mobility to physical therapy has challenged the usual culture of ED processes.

Discussion

Practice in the hospital ED enables physical therapists to fully use their knowledge, diagnostic skills, and ability to manage acute pain and musculoskeletal injury. Recommendations for future action are made to encourage more institutions across the country to incorporate physical therapy in EDs to enhance the process and outcome of nonemergent care.
Curriculum Integration within the Context of Veterinary Education
Authors: Cavalieri John
Published: January 2010

Curriculum integration has been applied across a range of educational levels as a means of attempting to improve learning outcomes, but there is a paucity of information that has defined and explored curriculum integration as it relates to the teaching of veterinary science. A definition of curriculum integration in the teaching of veterinary science is suggested, which places students as lifelong learners at the center of the educational model. Learning activities are designed to help students see connections among disciplines and topics, thus reinforcing their relevance and helping them to apply their knowledge to different contexts. Curriculum integration at James Cook University in the first three years of the program has been promoted through the design of assessment, the use of case studies, imaging, and palpable anatomy, learning of clinical skills, a research project, animal handling, and a personal professional development program. Advantages and disadvantages of curriculum integration are discussed. Further work is needed to determine if this mode of curriculum design is able to produce veterinary graduates who are better able to meet the challenges of a changing workplace in the twenty-first century.
Teaching Transrectal Palpation of the Internal Genital Organs in Cattle
Authors: Bossaert Philippe , Leterme Lieselot , Caluwaerts Tim , Cools Steven , Hostens Miel , Kolkman Iris , de Kruif Aart
Published: January 2010

In this article, a simulation model for rectal palpation teaching in cows, Breed'n Betsy®, is evaluated. Furthermore, the learning process of rectal palpation is depicted during a training period in live cows. In experiment 1, eight students were trained in live cows (group A) and nine students were trained using Breed'n Betsy (group B). After 25 palpations, their ability to localize and evaluate structures was evaluated in practical tests in live cows. Group A had higher results than group B (p<0.001) and were more skilled at localizing the uterus and localizing and evaluating the ovaries (p<0.05). Group B was better at pregnancy diagnosis (nonsignificant). Results suggest that Breed'n Betsy cannot fully replace training in live cows, but may be a valuable addition to the classical teaching method. Suggestions for future improvement are made. In experiment 2, 10 students were intensely trained in live cows throughout the year and evaluated in practical tests at three time points (September, January, and March). Results were analyzed as a function of time point and the category of experience (1: 0–50 cows; 2: 50–100 cows; 3: 100–150 cows; 4: 150–200 cows; 5: >200 cows). Results increased in time (p<0.05) and were higher in categories 3, 4, and 5 than in category 1 (p<0.05). Although all of the students in the higher categories successfully localized the cervix, uterus, and ovaries, they had difficulties in interpreting these structures, suggesting that palpation of 200 cows is insufficient to reach a consistent level of expertise.
Neurovascular Risks of Anteroinferior Clavicular Plating
Authors: Lo Eddie Y. , Eastman Jonathan , Tseng Susan , Lee Mark A. , Yoo Brad J.
Published: January 2010

Anteroinferior plating has been described for internal fixation of clavicular fractures, citing improved bicortical fixation, less hardware prominence, and safer drill trajectories compared with other plate configurations. This anatomic study defined structures at risk during anteroinferior clavicular plating. Four paired cadaveric specimens (8 clavicles) from ages 75 to 93 years were systematically dissected. Using the screw paths associated with an anteroinferior plate (anteroinferior to superoposterior), the distance from the posterior clavicle cortex to the nearest vital structure was measured at 5 different positions along the clavicle. In the medial half of the clavicle, the subclavian artery is in closest proximity to the clavicle, measuring, on average, 22.95 mm and 15.10 mm at point A and B. At the lateral three-fifths point of the clavicle (point C), the brachial plexus is 12.76 mm from the posterior clavicle and is more at risk than the subclavian artery. Lateral to the three-fifth point of the clavicle, there were no vital structures that could be injured by overdrilling. Our results suggest that more care should be observed with placement of screws in the medial half of the clavicle where subclavian artery damage is more likely.
Early Failures in Unicondylar Arthroplasty
Authors: Fehring Thomas K. , Odum Susan M. , Masonis John L. , Springer Bryan D.
Published: January 2010

Unicondylar arthroplasty has reemerged as an option for isolated compartment knee arthritis. We have noticed an increase in the need for early revision of this construct at our revision center. This study sought to determine if the need for unicondylar revision has increased over time and what factors may have led to early failure.

Revision total knee arthroplasties (TKAs) performed between 1990 and 1999 (period 1) were compared to TKAs performed between 2000 and 2008 (period 2). The prevalence of unicondylar revision, time to failure, and reasons for failure were calculated. Between 1990 and 1999, 425 revision TKAs were performed, 7 of which were uni-revisions (1.6%). These had been in place an average of 169 months (range, 12.9–478.6 months). Between 2000 and 2008, 744 revision TKAs were performed, 43 of which were uni-revisions (5.8%). These had been in place an average of only 36 months (range, 4.2–159.5 months). The dominant reasons for failure in period 1 included poly wear and loosening. Reasons for failure in period 2 were variable but included a number of technical errors.

Early failure of unicondylar arthroplasty appears to be on the rise. Acknowledging that these patients came from an unknown pool, we are concerned that market pressure may have led to inappropriate patient selection and that surgical inexperience with this procedure may have led to the technical problems noted in period 2. Patients should be apprised of the possibility of early revision with this procedure.
Metal-on-Metal Hip Resurfacing in Patients With Pigmented Villonodular Synovitis: A Report of Two Cases
Authors: Hoberg Maik , Amstutz Harlan C.
Published: January 2010

Pigmented villonodular synovitis (PVNS) of the hip joint is a rare and benign tumor of the synovia. This local, aggressive, proliferative disorder of the joint synovial membrane can lead to secondary osteoarthritis and represents a small percentage of all patients undergoing total hip replacement (THR). Because of the usually young age of the patients undergoing THR for PVNS, a resurfacing arthroplasty of the hip appears as a beneficial treatment option due to its bone-conserving nature, good joint stability, and ability to easily convert to a THR if needed. This article describes 2 cases of metal-on-metal hip resurfacing in patients with pigmented villonodular synovitis. In patient 1, PVNS was suspected on radiographs but confirmed only after removal of a mass of thick, grey-brown spotted synovia. A complete synovectomy was performed prior to hip resurfacing. Seven years postoperatively, radiographs show secure fixation of the components with no radiolucencies. In patient 2, arthroscopy of the hip joint had been performed 3 months prior, but PVNS had not been diagnosed. Pigmented villonodular synovitis was confirmed during the operation when incising a yellowish nodular mass protruding from the capsule. Granuloma was also found in the inferior and anterior part of the acetabulum. Four years postoperatively, the patient exhibits excellent clinical and radiographic results. Complete surgical removal of all tissue affected with PVNS is the key to a successful resurfacing, which is otherwise technically similar to resurfacing in patients with other etiologies. The mid-term results of the 2 presented cases are satisfying and show the potential of the resurfacing technique for young patients with PVNS of the hip.
Spindle-Cell Hibernoma: A Clinicopathologic Comparison of This New Variant
Authors: Moretti Vincent M. , Brooks John S.J. , Lackman Richard D.
Published: January 2010

Spindle-cell hibernoma is 1 of 4 histologic variants of hibernomas, which are rare lipomatous tumors distinguished from other lipomas by their brown fat component. This article presents a case of a spindle-cell hibernoma that developed in the groin of a 58-year-old man, and is 1 of only 5 known cases of spindle-cell hibernoma published in the scientific literature. Minimal information is available regarding the clinicopathologic characteristics of the 4 hibernoma variants: typical, lipoma-like, myxoid, and spindle-cell. Spindle-cell hibernoma is believed to be the rarest variant, accounting for approximately 2% of hibernomas. The spindle-cell variant predominantly develops in the fourth and fifth decades, with an average age at diagnosis of 42.5 years (range, 28–59 years). It has a male predilection of 4:1. Previously reported only in the posterior neck and scalp, the groin is now added to the sites of spindle-cell hibernoma occurrence. Our patient's tumor demonstrated low-attenuation on computed tomography and contained moderately-attenuating internal septae. Histologically, in addition to the multivacuolated brown fat component common to all hibernomas, spindle-cell hibernoma has a spindle-cell element without vacuolization that is CD34 positive. No prior treatment details are available on this particular variant. Our patient was treated by marginal excision and was disease free through 13 months of follow-up.
Preceptors' Perspectives on Recruitment, Support, and Retention of Preceptors
Authors: DeWolfe Judith A. , Laschinger Susan , Perkin Catherine
Published: January 2010

In this study, the researchers sought consensus among preceptors of senior nursing students about issues key to the preceptors' recruitment, support, and retention. A modified Delphi method with two rounds of questionnaires was used followed by a focus group to explore issues for which consensus was not reached. Preceptors agreed on the importance of personal satisfaction and on a number of tangible benefits of being a preceptor that could be emphasized as part of recruitment strategies. Consensus was reached on ways to support preceptors such as receiving information on a need-to-know basis. Topics such as how to help students think critically and how to provide constructive feedback also were considered important. Preceptors agreed that having students well prepared at the beginning of preceptored experiences was important as was receiving a personalized thank you letter to acknowledge their work at the end of the experience, two strategies that could help with retention.
Rhegmatogenous Retinal Detachment Following Treatment for Retinoblastoma
Authors: Saumya Pal Swakshyar , Gopal Lingam , Khetan Vikas , Nagpal Amit , Sharma Tarun
Published: January 2010

Purpose:

To elucidate characteristics of rhegmatogenous retinal detachment that developed in children who underwent treatment for retinoblastoma and to analyze the outcome following vitreoretinal surgery in such clinical settings.

Methods:

This was a retrospective case series of 9 eyes of 9 patients who underwent vitreoretinal surgery for tumor control and retinal reattachment.

Results:

At the time of diagnosis of rhegmatogenous retinal detachment, retinoblastoma was regressed in 6 eyes (67%). The retinal detachment involved less than two quadrants in 7 eyes (78%) and was caused by an atrophic break in 7 eyes. Seven eyes underwent a non-drainage scleral buckling procedure. Three eyes underwent vitreous surgery; in 2 of these eyes, tumor excision along with retinectomy using melphalan infusion was performed and eventually silicone oil tamponade was used. Retinal reattachment was achieved in all eyes with eventual tumor control in 7 eyes. The median follow-up after retinal reattachment surgery was 24 months.

Conclusion:

Rhegmatogenous retinal detachment in treated eyes with retinoblastoma is usually caused by an atrophic retinal break. Retinal detachment can be repaired successfully in most eyes.
Reliability and Validity of the Health Enhancement Lifestyle Profile (HELP)
Authors: Hwang Jengliang Eric
Published: January 2010

The Health Enhancement Lifestyle Profile (HELP) is a self-report measure for examining various aspects of health-related lifestyle in older adults through seven scales (Exercise; Diet; Work, Education, and Social Participation; Leisure; Activities of Daily Living; Psychological Wellness and Spiritual Participation; and Other Health Promotion and Risk Behaviors). The current study examined the reliability and validity of the HELP scales through classic test theory. The resultant alpha coefficients ranged from .75 to .92 among the scales, indicating acceptable to good internal consistency reliability. Construct validity was also supported by the interrelationships found among the HELP scales and the statistically significant correlations shown between HELP results and global health status (i.e., number of chronic conditions, self-related health). HELP scales can help occupational therapists identify and monitor health promotion occupations and risk behaviors and measure the outcome of services aimed at promoting healthy lifestyles in older adults.
A cellular level approach to predicting resting energy expenditure: Evaluation of applicability in adolescents
Authors: Wang ZiMian , Heymsfield Steven B. , Ying Zhiliang , Pierson Richard N. , Gallagher Dympna , Gidwani Sonia
Published: January 2010

We previously derived a cellular level approach for a whole‐body resting energy expenditure (REE) prediction model by using organ and tissue mass measured by magnetic resonance imaging (MRI) combined with their individual cellularity and assumed stable‐specific resting metabolic rates. Although this approach predicts REE well in both young and elderly adults, there were no studies in adolescents that specifically evaluated REE in relation to organ–tissue mass. It is unclear whether the approach can be applied to rapidly growing adolescents. The aim of the present study was to evaluate the applicability of the previous developed REE prediction model in adolescents, and to compare its applicability in young and elderly adults. Specifically, we tested the hypothesis that measured REE can be predicted from a combination of individual organ and tissue mass and their related cellularity. This was a 2‐year longitudinal investigation. Twenty healthy male subjects with a mean age of 14.7 years had REE, organ and tissue mass, body cell mass, and fat‐free mass (FFM) measured by indirect calorimetry, whole‐body MRI, whole‐body 40K counting and dual‐energy X‐ray absorptiometry, respectively. The predicted REE (REEp; mean ± SD, 1,487 ± 238 kcal/day) was correlated with the measured REE (REEm, 1,606 ± 237 kcal/day, r = 0.76, P < 0.001). The mean difference (118 ± 165 kcal/day) between REEm and REEp was significant (P = 0.0047), accounting for 7.3% of REEm for the entire group. The present study, the first of its type in adolescents, does not support the applicability of the organ–tissue‐based REE prediction model during rapid adolescent growth. A modified general REE prediction model is thus suggested which may account for the higher REE/FFM ratio observed in adolescents. Am. J. Hum. Biol. 2010. © 2010 Wiley‐Liss, Inc.
Influence of surface morphology of the kraft pulp fibers on the growth of the transcrystalline layer of polypropylene
Authors: Lee Byung G. , Lee Sangyeob , Via Brian K.
Published: January 2010

The objective of this study was to evaluate the influence of the wood fiber surface on the crystallization behavior of thermoplastic polymers. Unbleached and bleached kraft pulp fibers were used for this study with 100% polypropylene (PP), 95% PP/5% maleic anhydride polypropylene (MAPP), and 100% MAPP at 150°C. Nuclei were induced at the ends of the fibers and on damaged surfaces while poor crystallization behavior was observed on the fiber surfaces using 100% PP. Enhanced MAPP induced transcrystallization on the wood fiber surfaces; the nucleation density also increased with the addition of MAPP. Oxygen/carbon (O/C) ratios of smooth surfaces, damaged surfaces, and the ends of wood fibers also indicated that the oxidation process of both wood fiber and thermoplastic polymer affected the crystallization process without MAPP addition. It was observed that the MAPP played a role in increasing numbers of nuclei on the linear fiber surface to induce transcrystallization. Dynamic mechanical properties increased 52% with 100% MAPP compared to the use of 100% PP. Therefore, the increased thickness of transcrystalline layer and nucleation density on the surface of wood fiber positively correlated with the dynamic mechanical properties of wood fiber‐plastic composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Novel thermo‐responsive semi‐interpenetrating network microspheres of gellan gum‐poly(N‐isopropylacrylamide) for controlled release of atenolol
Authors: Mundargi Raghavendra C. , Shelke Namdev B. , Babu V. Ramesh , Patel Pradip , Rangaswamy Vidhya , Aminabhavi Tejraj M.
Published: January 2010

Thermoresponsive microspheres of gellan gum‐poly(N‐isopropylacrylamide), i.e., GG‐P(NIPAAm) semi‐interpenetrating polymer networks (semi‐IPNs) have been prepared by ionic crosslinking and used to study the controlled release (CR) of atenolol (ATL), an antihypertensive drug. Interaction of the drug with polymers was studied by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) was used to confirm the polymorphism and molecular level dispersion of ATL. Scanning electron microscopy (SEM) indicated spherical nature and smooth surfaces of the microspheres with some debris attached on their surfaces. Mean particle size measured by laser light diffraction ranged between 34 and 76 μm. Equilibrium swelling performed at 25°C and 37°C in pH 7.4 phosphate buffer exhibited thermoresponsive nature of the polymers. In vitro drug release performed at 25°C and 37°C indicated temperature‐dependency of ATL release, which was extended up to 12 h. In vitro release profiles at both the temperatures confirmed thermoresponsive nature of the polymers giving pulsatile trends. The % cumulative release data have been fitted to an empirical equation to estimate transport parameters and to understand the nature of drug release. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation of new water‐soluble chitosan containing hyperbranched‐vinylsulfonic acid sodium salt and their antimicrobial activities and chelation with metals
Authors: Chanthateyanonth Ratana , Ruchirawat Somsak , Srisitthiratkul Chutima
Published: January 2010

In this work, an efficient and simple method to graft a vinylsulfonic acid sodium salt on a poorly water‐soluble chitosan is described. Commercially available low molecular weight chitosan is converted to water‐soluble chitosan containing hyperbranched‐vinylsulfonic acid sodium salt groups. The process comprises the following steps: Michael addition of methyl acrylate, amidation with ethylenediamine, and Michael addition of vinylsulfonic acid sodium salt. A variety of chitosans containing vinylsulfonic acid sodium salt, with improved water solubility, is synthesized by repeating these three steps. The new chitosan derivatives show better antimicrobial activity against Micrococcus luteus ATCC 10240 and Achromobacter xylosoxidans ATCC 2706. In addition, they display better chelating behavior with heavy metals, like cadmium(II), copper(II), and nickel(II), than the starting chitosan. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effects of organo‐clay modifier on physical–mechanical properties of butyl‐based rubber nano‐composites
Authors: Samadi Ali , Razzaghi Kashani Mehdi
Published: January 2010

Bladders are important rubber parts used for shaping and curing of tires. These parts are exposed to high temperature, high pressure, medium‐large extension, and oxidative aging during their service life. Curing bladders are usually made of butyl‐based rubber compounds vulcanized with phenolic resin vulcanization systems. To study the effect of Montmorillonite nano‐clay on properties of these rubber parts and their functionality during service, the most compatible and well dispersed organically modified Montmorillonite (OMMT) nano‐clay has to be selected. To study the effects of organic modifier on properties of these compounds, five types of commercial OMMT were mixed with the compounds using the melt intercalation method. Effect of modifiers on compatibility between clay and rubber, dispersion of clay in the polymer matrix, and thus mechanical properties of the nano‐composite were studied by X‐ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), mechanical tension, and dynamic‐mechnical‐thermal analysis (DMTA). XRD results revealed an intercalated structure for all OMMTs, but with different degrees of rubber intercalation. The largest change in interlayer spacing of silicate layers due to intercalation of rubber was seen for an OMMT modified by dimethyl‐benzyl‐hydrogenated tallow, quaternary ammonium. AFM and SEM micrographs of the latter compound confirmed the intercalated structure with a good distribution of filler. Viscoelastic properties obtained from DMTA confirmed more compatibility between butyl‐based rubber compound and this OMMT. This modified clay was selected as the filler of choice for potential application in actual bladder compound. Uni‐axial tension tests could also differentiate among nano‐composites reinforced with differently modified clays. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Electrospun ultrathin nylon fibers for protective applications
Authors: Vitchuli Narendiran , Shi Quan , Nowak Joshua , McCord Marian , Bourham Mohamed , Zhang Xiangwu
Published: January 2010

Electrospun nylon 6 fiber mats were deposited on woven 50/50 nylon/cotton fabric with the motive of making them into protective material against submicron‐level aerosol chemical and biological threats. Polymer solution concentration, electrospinning voltage, and deposition areal densities were varied to establish the relationships of processing‐structure‐filtration efficiency of electrospun fiber mats. A high barrier efficiency of greater than 99.5% was achieved on electrospun fiber mats without sacrificing air permeability and pressure drop. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Apolipoprotein E–deficient mice are resistant to the development of collagen‐induced arthritis
Authors: Asquith Darren L. , Miller Ashley M. , Hueber Axel J. , Liew Foo Y. , Sattar Naveed , McInnes Iain B.
Published: January 2010

Objective

To determine whether elevated serum lipid levels resulting from feeding animals a high‐fat diet can affect the inflammatory process in C57BL/6 (B6) wild‐type (WT) and B6 ApoE−/− mouse models of collagen‐induced arthritis (CIA).

Methods

Male B6 WT or ApoE−/− mice were fed either a normal chow diet or a high‐fat diet. CIA was induced in mice at 12 weeks of age using type II chicken collagen, Freund's complete adjuvant, and, on occasion, a lipopolysaccharide boost. Expression levels of autoantibodies and cytokines were measured using enzyme‐linked immunosorbent assay and multiplex assay, respectively.

Results

Whereas B6 WT mice developed severe articular inflammation after collagen immunization, ApoE−/− mice developed no clinical or histologic evidence of disease regardless of whether they had been fed a high‐fat diet or a normal chow diet. The fact that arthritis was not present in ApoE−/− mice did not result from inadequate production of serum IgG2a collagen antibodies, since levels observed in ApoE−/− mice were similar to those observed in arthritic B6 WT control mice. Critically, development of atherosclerosis in ApoE−/− mice was not affected by the CIA protocol.

Conclusion

Our findings suggest that ApoE−/− mice are resistant to the development of CIA. Intriguingly, induction of host autoimmunity in the absence of articular inflammation had no effect on atherosclerosis progression, suggesting that articular inflammatory load may be a critical risk factor in vascular pathology.
Enhanced Th1 and Th17 responses and arthritis severity in mice with a deficiency of myeloid cell–specific interleukin‐1 receptor antagonist
Authors: Lamacchia Céline , Palmer Gaby , Seemayer Christian A. , Talabot‐Ayer Dominique , Gabay Cem
Published: January 2010

Objective

The balance between interleukin‐1 (IL‐1) and its specific inhibitor, the IL‐1 receptor antagonist (IL‐1Ra), plays a major role in the development of arthritis. The purpose of this study was to investigate the role of IL‐1Ra produced specifically by myeloid cells in the control of collagen‐induced arthritis (CIA) by using myeloid cell–specific IL‐1Ra–deficient mice (IL‐1RaΔM).

Methods

IL‐1RaΔM mice were generated by using the loxP/Cre recombinase system. CIA was induced in IL‐1RaΔM mice and littermate control mice by a single immunization with bovine type II collagen (CII) in Freund's complete adjuvant. Arthritis severity was assessed by clinical and histologic scoring. Draining lymph node (DLN) cell responses were examined ex vivo, and ankle extracts were used in the quantification of cytokines and chemokines.

Results

Clinical and histopathologic evaluations revealed an early disease onset and a severe form of CIA in IL‐1RaΔM mice. This was characterized by increased production of interferon‐γ (IFNγ) and IL‐17 by CII‐stimulated DLN cells. We also observed that the CII‐specific CD4+ T cell response shifted in vivo, from a dominant Th1 response early in the course of the arthritis to the presence of both Th1 and Th17 cytokines later in the disease course. Interestingly, IL‐1Ra levels were higher in the arthritic joints of IL‐1RaΔM mice as compared with the controls, indicating that nonmyeloid cells strongly contribute to the local production of IL‐1Ra. However, this enhanced IL‐1Ra production was not sufficient to limit joint inflammation and tissue damage.

Conclusion

Our results suggest that myeloid cell–derived IL‐1Ra plays a critical role in the control of the development and the severity of CIA by modulating Th1 and Th17 responses in lymphoid organs.
Activation of AMP‐activated protein kinase by adiponectin rescues salivary gland epithelial cells from spontaneous and interferon‐γ–induced apoptosis
Authors: Katsiougiannis Stergios , Tenta Roxane , Skopouli Fotini N.
Published: January 2010

Objective

Primary Sjögren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltrates associated with destruction of salivary gland epithelial cells (SGECs) induced mainly by apoptosis. Adiponectin is an immunoregulatory hormone. We have previously shown that SGECs from patients with primary SS as well as from controls differentially express adiponectin. SGECs derived from patients with primary SS constitutively produce and secrete adiponectin in higher quantities. The aim of this study was to investigate the effect of adiponectin on the proliferation and apoptosis of SGECs.

Methods

Cultured, non‐neoplastic SGECs were treated with recombinant human adiponectin, and the rate of cell proliferation was assessed. Spontaneous and interferon‐γ (IFNγ)–induced apoptosis was evaluated with a specific single‐stranded DNA enzyme‐linked immunosorbent assay. The AMP‐activated protein kinase (AMPK) inhibitor Compound C was used to test the involvement of AMPK in adiponectin effects. Western blotting was applied to detect the phosphorylation levels of AMPK after adiponectin treatment.

Results

Adiponectin treatment resulted in a dose‐dependent suppression of proliferation of SGECs from patients with primary SS and control donors. Adiponectin protected cells from spontaneous as well as from IFNγ‐induced apoptosis. Furthermore, the antiapoptotic effects of adiponectin were dependent upon AMPK phosphorylation at Thr172, since pretreatment of SGECs with Compound C abolished the adiponectin protective effect.

Conclusion

Adiponectin exerted antiproliferative effects on SGECs without inducing apoptosis and protected SGECs from spontaneous as well as from IFNγ‐induced apoptosis through an AMPK‐dependent pathway. Our observations suggest that adiponectin may protect SGECs in this specific inflammatory milieu, providing a potential pathway through which AMPK may regulate cell survival under energy stress conditions such as autoimmune inflammation.
Periarticular bone structure in rheumatoid arthritis patients and healthy individuals assessed by high‐resolution computed tomography
Authors: Stach Christian M. , Bäuerle Michael , Englbrecht Matthias , Kronke Gerhard , Engelke Klaus , Manger Bernhard , Schett Georg
Published: January 2010

Objective

To define the nature of structural bone changes in patients with rheumatoid arthritis (RA) compared with those in healthy individuals by using the novel technique of high‐resolution microfocal computed tomography (micro‐CT).

Methods

Fifty‐eight RA patients and 30 healthy individuals underwent a micro‐CT scan of the proximal wrist and metacarpophalangeal joints. Bone lesions such as cortical breaks, osteophytes, and surface changes were quantified on 2‐dimensional (2‐D) slices as well as by using 3‐D reconstruction images, and exact localization of lesions was recorded.

Results

Micro‐CT scans could detect bone lesions <0.5 mm in width or depth. Small erosions could be observed in healthy individuals and RA patients, whereas lesions >1.9 mm in diameter were highly specific for RA. Cortical breaks were mostly found along the radial sites of the metacarpal heads. No significant difference in the presence of osteophytes between healthy individuals and RA patients was found. Cortical surface changes, presumably cortical thinning and fenestration, became evident from 3‐D reconstructions and were more pronounced in RA patients.

Conclusion

Micro‐CT allows exact detection of morphologic changes of juxtaarticular bone in healthy individuals and RA patients. Even healthy individuals occasionally show bone changes, but the severity of these lesions, with the exception of osteophytes, is greater in RA patients. Thus, micro‐CT allows accurate differentiation among physiologic bone changes in joints and among types of pathologic bone damage resulting from RA.
Comparative analysis of gene expression profiles between primary knee osteoarthritis and an osteoarthritis endemic to Northwestern China, Kashin‐Beck disease
Authors: Duan Chen , Guo Xiong , Zhang Xiao‐Dong , Yu Han‐Jie , Yan Hua , Gao Ying , Ma Wei‐Juan , Gao Zong‐Qiang , Xu Peng , Lammi Mikko
Published: January 2010

Objective

To investigate the differences in gene expression profiles of adult articular cartilage from patients with Kashin‐Beck disease (KBD) versus those with primary knee osteoarthritis (OA).

Methods

The messenger RNA expression profiles of articular cartilage from patients with KBD, diagnosed according to the clinical criteria for KBD in China, were compared with those of cartilage from patients with OA, diagnosed according to the Western Ontario and McMaster Universities OA Index. Total RNA was isolated separately from 4 pairs of the KBD and OA cartilage samples, and the expression profiles were evaluated by Agilent 4×44k Whole Human Genome density oligonucleotide microarray analysis. The microarray data for selected transcripts were confirmed by quantitative real‐time reverse transcription–polymerase chain reaction (RT‐PCR) amplification.

Results

For 1.2 × 104 transcripts, corresponding to 58.4% of the expressed transcripts, 2‐fold changes in differential expression were revealed. Expression levels higher in KBD than in OA samples were observed in a mean ± SD 6,439 ± 1,041 (14.6 ± 2.4%) of the transcripts, and expression levels were lower in KBD than in OA samples in 6,147 ± 1,222 (14.2 ± 2.8%) of the transcripts. After application of the selection criteria, 1.85% of the differentially expressed genes (P < 0.001 between groups) were detected. These included 233 genes, of which 195 (0.4%) were expressed at higher levels and 38 (0.08%) were expressed at lower levels in KBD than in OA cartilage. Comparisons of the quantitative RT‐PCR data supported the validity of our microarray data.

Conclusion

Differences between KBD and OA cartilage exhibited a similar pattern among all 4 of the pairs examined, indicating the presence of disease mechanisms, mainly chondrocyte matrix metabolism, cartilage degeneration, and apoptosis induction pathways, which contribute to cartilage destruction in KBD.
An eye‐tracking study on information processing in risky decisions: Evidence for compensatory strategies based on automatic processes
Authors: Glöckner Andreas , Herbold Ann‐Katrin
Published: January 2010

Many everyday decisions have to be made under risk and can be interpreted as choices between gambles with different outcomes that are realized with specific probabilities. The underlying cognitive processes were investigated by testing six sets of hypotheses concerning choices, decision times, and information search derived from cumulative prospect theory, decision field theory, priority heuristic and parallel constraint satisfaction models. Our participants completed 40 decision tasks of two gambles with two non‐negative outcomes each. Information search was recorded using eye‐tracking technology. Results for choices, decision time, the amount of information searched for, fixation durations, the direction of the information search, and the distribution of fixations conflict with the prediction of the non‐compensatory priority heuristic and indicate that individuals use compensatory strategies. Choice proportions are well in line with the predictions of cumulative prospect theory. Process measures indicate that individuals thereby do not rely on deliberate calculations of weighted sums. Information integration processes seem to be better explained by models that partially rely on automatic processes such as decision field theory or parallel constraint satisfaction models. Copyright © 2010 John Wiley & Sons, Ltd.
Real‐Time Monitoring of RNA Synthesis in a Phospholipid‐Coated Microdroplet as a Live‐Cell Model
Authors: Tsuji Akihiko , Yoshikawa Kenichi
Published: January 2010

We constructed a phospholipid‐coated water‐in‐oil microdroplet (20‐60 μm in diameter) that encapsulated plasmid DNA containing a human β‐actin cDNA sequence, fluorescent oligonucleotide probes, and other components of the transcription reaction. Transcription inside individual microdroplets was investigated in real time by using fluorescence microscopy. The progress of the transcription reaction was successively monitored by fluorescence resonance energy transfer (FRET), which was derived from the specific hybridization of fluorescent oligonucleotide probes to the β‐actin mRNAs synthesized. In microdroplets composed of phosphatidylethanolamine, DNAs were located in the aqueous phase or on the membrane surface depending on the MgII concentration. FRET images showed that transcription occurred on DNA in both states. Moreover, individual DNA molecules undergoing transcription were visualized as discrete FRET signals in cases in which small numbers of DNAs were present in the microdroplet.