bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial Distribution ofHelicobacterspp. in the Gastrointestinal Tract of Dogs
Authors: Recordati Camilla , Gualdi Valentina , Craven Melanie , Sala Lorenza , Luini Mario , Lanzoni Anna , Rishniw Mark , Simpson Kenneth W. , Scanziani Eugenio
Published: May 2009

Background: In dogs, the gastricHelicobacterspp. have been well studied, but there is little information regarding the other parts of the alimentary system. We sought to determine the spatial distribution ofHelicobacterspp. in the gastrointestinal tract and the hepatobiliary system of dogs using culture‐independent methods.

Materials and methods: Samples of stomach, duodenum, ileum, cecum, colon, pancreas, liver, and bile from six dogs were evaluated forHelicobacterspp. by genus, gastric, and enterohepaticHelicobacterspp. Polymerase chain reaction, 16S rRNA gene sequence analysis, immunohistochemistry, and fluorescencein situhybridization (FISH).

Results: In the stomach,Helicobacterspp. DNA was detected in all six dogs, withH. bizzozeroniiandH. felisidentified by specific polymerase chain reaction.Helicobacterorganisms were localized within the surface mucus, the lumen of gastric glands, and inside parietal cells. The small intestine harbored gastric and enterohepaticHelicobacterspp. DNA/antigen in low amounts. In the cecum and colon,Helicobacterspp. DNA, with highest similarity toH. bilis/flexispira taxon 8,H. cinaedi, andH. canis,was detected in all six dogs.Helicobacterorganisms were localized at the mucosal surface and within the crypts. GastricHelicobacterspp. DNA was detected occasionally in the large intestine, but no gastricHelicobacterspp. were present in clone libraries or detected by FISH.

Conclusions: This study demonstrates that in addition to the stomach, the large intestine of dogs is also abundantly colonized byHelicobacterspp. Additional studies are necessary to investigate the association between enterohepaticHelicobacterspp. and presence of intestinal inflammatory or proliferative disorders in dogs.
Evidence for Transepithelial Dendritic Cells in Human H. pylori Active Gastritis
Authors: Necchi Vittorio , Manca Rachele , Ricci Vittorio , Solcia Enrico
Published: May 2009

Background:  Despite extensive experimental investigation stressing the importance of bacterial interaction with dendritic cells (DCs), evidence regarding direct interaction of Helicobacter pylori or its virulence products with DCs in the human gastric mucosa is lacking.

Methods:  Human gastric mucosa biopsies, with or without H. pylori infection and active inflammation, were investigated at light and electron microscopy level with immunocytochemical tests for bacterial products (VacA, urease, outer membrane proteins) and DC markers (DC‐SIGN, CD11c, CD83) or with the DC‐labeling ZnI2‐OsO4 technique. Parallel tests with cultured DCs were carried out.

Results:  Cells reproducing ultrastructural and cytochemical patterns of DCs were detected in the lamina propria and epithelium of heavily infected and inflamed (but not of normal) mucosa, where DC luminal endings directly contact H. pylori and take up their virulence products. Cytotoxic changes (mitochondrial swelling, cytoplasmic vacuolation, autophagy) were observed in intraepithelial DCs and reproduced in cultured DCs incubated with H. pylori broth culture filtrates to obtain intracellular accumulation of VacA and urease. Granulocytes were also seen to contact and heavily phagocytose luminal H. pylori, while macrophages remained confined to basal epithelium, though taking up bacteria and bacterial products.

Conclusion:  Human DCs can enter H. pylori‐infected gastric epithelium, in association with other innate immunity cells, to take up bacteria and their virulence products. This process is likely to be important for bacterial sensing and pertinent immune response; however, it may also generate DC cytotoxic changes potentially hampering their function.
Age and early metamorphic history of the Sanbagawa belt: Lu–Hf and P–T constraints from the Western Iratsu eclogite
Authors: ENDO S. , WALLIS S. , HIRATA T. , ANCZKIEWICZ R. , PLATT J. , THIRLWALL M. , ASAHARA Y.
Published: May 2009

Two distinct age estimates for eclogite‐facies metamorphism in the Sanbagawa belt have been proposed: (i) c. 120–110 Ma based on a zircon SHRIMP age for the Western Iratsu unit and (ii) c. 88–89 Ma based on a garnet–omphacite Lu–Hf isochron age from the Seba and Kotsu eclogite units. Despite the contrasting estimates of formation ages, petrological studies suggest the formation conditions of the Western Iratsu unit are indistinguishable from those of the other two units—all ∼20 kbar and 600–650 °C. Studies of the associated geological structures suggest the Seba and Western Iratsu units are parts of a larger semi‐continuous eclogite unit. A combination of geochronological and petrological studies for the Western Iratsu eclogite offers a resolution to this discrepancy in age estimates. New Lu–Hf dating for the Western Iratsu eclogite yields an age of 115.9 ± 0.5 Ma that is compatible with the zircon SHRIMP age. However, petrological studies show that there was significant garnet growth in the Western Iratsu eclogite before eclogite facies metamorphism, and the early core growth is associated with a strong concentration of Lu. Pre‐eclogite facies garnet (Grt1) includes epidote–amphibolite facies parageneses equilibrated at 550–650 °C and ∼10 kbar, and this is overgrown by prograde eclogite facies garnet (Grt2). The Lu–Hf age of c. 116 Ma is strongly skewed to the isotopic composition of Grt1 and is interpreted to reflect the age of the pre‐eclogite phase. The considerable time gap (c. 27 Myr) between the two Lu–Hf ages suggests they may be related to separate tectonic events or distinct phases in the evolution of the Sanbagawa subduction zone.
Utilization of antiepileptic drugs during pregnancy: Comparative patterns in 38 countries based on data from the EURAP registry
Authors: The EURAP Study Group
Published: May 2009

We assessed the utilization of antiepileptic drugs (AEDs), 1999–2005, in 4,798 prospective epilepsy pregnancies from 38 countries participating in EURAP, an international AED and pregnancy registry. Prominent differences in utilization patterns were observed across the various countries. Exposure to second‐generation AEDs ranged from 3.5% in India and 7.3% in Italy to 75% in Denmark. Even wider variation was recorded in exposure to individual AEDs. The utilization of second‐generation AEDs increased over time (for lamotrigine, from 9.9% of all pregnancies before 2001 to 29.6% after 2003). The differences in use of individual AEDs across countries probably reflect lack of evidence concerning the optimal treatment of epilepsy in women of childbearing age, as well as variation in country‐specific traditions, medication costs, and drug promotion. Our observations underscore the need for comparative studies to investigate the factors influencing the prescription of AEDs during pregnancy, as well as their influence on pregnancy outcome.
Effects of valproic acid on sleep in children with epilepsy
Authors: Schmitt Bernhard , Martin Florence , Critelli Hanne , Molinari Luciano , Jenni Oskar G.
Published: May 2009

Purpose:  Parents frequently report increased sleep duration in their children during treatment with valproic acid (VPA). We assessed sleep duration and sleep behavior before and after tapering VPA in children treated for more than 6 months.

Methods:  Sleep variables were assessed by questionnaire, diary, and actigraphy (for 7 consecutive days and nights) before and 8–12 weeks after termination of VPA.

Results:  Forty‐six children (age range 1.7–17.4 years) completed the study. The questionnaire data showed no significant difference in bed and wake time, duration of sleep, and time to fall asleep before and after ending VPA treatment, although some qualitative measures on daytime sleepiness improved after tapering VPA. The actigraphy data revealed that the average sleep amount without VPA was reduced in 33 children (9 of them >30 min) and longer in 13 children (1 of them >30 min). The mean Assumed Sleep Time per Day decreased by 15.2 min or 9.5 min when the physiologic decrease of sleep duration within 0.3 years was considered. Also mean Actual Sleep Time per Day was significantly reduced after VPA termination (−15.2min; after correction −10.7 min). The reduction was only significant in children older than age 6 years.

Discussion:  Termination of VPA after long‐term treatment leads to a significant reduction of sleep duration in children older than 6 years of age. The change was small in the majority, but considerable in a subgroup of children.
Epileptic discharges and phasic sleep phenomena in patients with juvenile myoclonic epilepsy
Authors: Bonakis Anastasios , Koutroumanidis Michalis
Published: May 2009

Purpose: Epileptiform discharges (EDs) may be part of the internal arousing stimuli that affect the quality of sleep in patients with epilepsies. We studied the association between EDs and sleep phasic phenomena, and its relevance to seizure control in 19 patients with juvenile myoclonic epilepsy (JME).

Methods: We analyzed the first cycle of non‐REM (rapid eye movement) sleep in 22 sleep‐deprived electroencephalography (EEG) studies and classified EDs within the cyclical alternating pattern (CAP) frame, grouping separately the EDs that occurred at the transition between phases (B to A and A to B).

Results: Within CAP periods, 36.7% of EDs occurred in A phase, 26.7% in B phase, 31.5% at “B to A” transition, and 3% at “A to B” transition. Poor seizure control was strongly associated with increased EDs in phase B (p = 0.0016) and at the “B to A” transition (p = 0.002), but marginally with increased EDs in phase A (p = 0.03). Focal spikes were increased in phase B.

Discussion: EDs are facilitated by increased vigilance (A phase), but they may also enhance CAP cycling by generating A phases when those that occur at the “B to A” transition are interpreted as successfully breaking through the state of reduced arousal (phase B) because of increased epileptic pressure. This promotes sleep instability and further fosters epileptic activity, and conceivably seizures. This hypothesis is also supported by the strong correlation between EDs during phase B (including “B” and “B to A”) and poor seizure control. The enhanced nonlocalizing focal spikes in phase B may reflect successful inhibition of generalized EDs.
Dominant Frequency Mapping of Atrial Fibrillation: Comparison of Contact and Noncontact Approaches
Authors: GOJRATY SATTAR , LAVI NIMROD , VALLES ERMENGOL , KIM STEVEN J. , MICHELE JOHN , GERSTENFELD EDWARD P.
Published: May 2009

Introduction:
The ability to acquire a dominant frequency (DF) map during atrial fibrillation (AF) instantaneously using noncontact mapping has significant advantages over the current sequential contact mapping approach; however, the relationship between DFs determined from contact bipolar and noncontact unipolar recordings is unknown. We sought to determine the difference between DFs determined using contact bipolar, contact unipolar, noncontact unipolar, and noncontact pseudobipolar recordings.

Methods:
Sustained AF was induced in 5 canines with 10 weeks of atrial tachy‐pacing at 440 ppm. A noncontact multielectrode array was positioned in the left atrium (LA). Two simultaneous contact signals (unipolar and bipolar) and 3 noncontact signals (unipolar, pseudobipolar, and pseudobipolar Laplacian) were recorded from multiple LA sites. Fourier analysis was performed, and the DFs of contact and noncontact signals were compared.

Results:
Recordings were obtained from 389 LA locations in 5 canines. The correlation was best between contact bipolar and noncontact QRS‐subtracted unipolar signals (r = 0.58, P < 0.001), and weaker between contact bipolar and noncontact best‐fit pseudobipolar (r = 0.50, P < 0.01) and noncontact Laplacian bipolar (r = 0.49, P < 0.01). There was no significant difference in the mean DFs between contact bipolar and noncontact unipolar signals; however, there was a significant difference in the DFs comparing contact bipolar to noncontact pseudobipolar signals (11.6 ± 1.8 vs 11.2 ± 2.5 Hz; P = 0.004) and a small nonsignificant difference comparing contact bipolar DF and noncontact pseudobipolar Laplacian DF (11.4 ± 1.8 vs 11.1 ± 1.6 Hz; P = NS).

Conclusions:
We found that estimation of DFs using noncontact mapping is feasible and that QRS‐subtracted noncontact unipolar signals perform better than noncontact pseudobipolar signals at estimating contact bipolar DFs. This has important implications for developing algorithms for noncontact frequency mapping of AF.
Defining Cultural Competence in Context: Dyadic Norms of Friendship Among U.S. High School Students
Authors: Hruschka Daniel
Published: May 2009

AbstractCultural competence is often defined as the ability to adhere to a core set of beliefs and practices. In this article, I argue that in many cases competence also involves the creative and occasionally idiosyncratic use of conventional knowledge to meet both personal goals and the specific requirements of local relationships and settings. I illustrate this tension between adopting broadly shared cultural norms and adapting them to local circumstances by examining how U.S. high school students prioritize their expectations of “good friends.” Drawing from cultural consensus approaches in cognitive anthropology, I analyze patterns of agreement among students to show that despite some population‐wide sharing, friends share more similar priorities than do nonfriends, and individuals also maintain stable differences in their personal priorities. These patterns of agreement and disagreement support the view that individuals strike a balance between fitting their personal models of friendship to broad cultural norms and accommodating the goals and needs of particular partners. More generally, I argue that competence in a cultural domain (in this case appropriate friendship behaviors) must be examined in relation to the specific contexts of use and the scale of social interaction for that domain. [competence, cultural consensus, friendship, quadratic assignment procedure, adolescence]
Suppression of ovulation by a synthetic progestin in the capuchin monkey
Authors: Nagle Carlos A. , Lahoz Monica M. , Porta Maria M. , Torres Marta , Manzur Teresita , Farinati Zulema
Published: May 2009

Background  From the limited research in New World monkeys it is not clear whether they are as sensitive to the antiovulatory effects of synthetic progestins as noted in human beings. We examined whether levonorgestrel prevented ovulation in the capuchin monkey.

Methods  Cebus apella monkeys were treated orally with two doses of 2 mg of levonorgestrel, 8–9 hours apart, in four periovulatory stages assessed by laparoscopy.

Results  Levonorgestrel‐induced luteinization of the follicle prevented oocyte release up to 8 hours before ovulation. Unhealthy oocytes were recovered from 46% of unruptured follicles. Luteal progesterone was reduced by 55%, 35%, and 25% according to when levonorgestrel was given −2, −1, and 0 day from estradiol peak respectively.

Conclusion  The capuchin monkey, a neotropical primate in which progesterone circulates at levels much higher than in Old World primates and human beings, is sensitive to the antiovulatory effects of synthetic progestins.
Risk of Implant Failure and Marginal Bone Loss in Subjects with a History of Periodontitis: A Systematic Review and Meta‐Analysis
Authors: Safii Syarida H. , Palmer Richard M. , Wilson Ron F.
Published: May 2009

Background: A number of studies have suggested that implant failure and associated bone loss is greater in subjects with a history of periodontitis.

Purpose: To evaluate the risk for marginal bone loss around implants and implant failure in subjects with a history of periodontitis compared with periodontally healthy subjects in studies with a minimum 3‐year follow‐up.

Materials and Methods: Data sources: The MEDLINE, EMBASE, and PubMed databases and relevant journals were searched up to July 1, 2008, with restriction to English language.

Review Methods: Prospective and retrospective longitudinal observational clinical studies comparing periodontal/peri‐implant variables among subjects with periodontitis and subjects who were periodontally healthy were included. Screening of studies, quality assessment, and data extraction were conducted independently and in duplicate. Clarification of missing and unclear information was not sought. Outcome measures were: implant survival/failure, peri‐implant parameters, changes in radiographic marginal bone level, probing pocket depth, and gingival index.

Results: Seventeen potential studies were identified and six studies were accepted comparing patients with periodontitis and periodontally healthy patients treated with implants. Five studies were eligible for meta‐analysis of implant survival and four studies were eligible for meta‐analysis of bone loss around implants. The odds ratio for implant survival was significantly in favor of periodontally healthy patients (3.02, 95% confidence intervals 1.12–8.15). A random effects model showed more marginal bone loss in periodontitis subjects compared with periodontally healthy subjects (standard mean difference 0.61, 95% confidence interval 0.14–1.09).

Conclusions: Within the limitations of the heterogenous studies available, a moderate level of evidence indicates that periodontitis subjects were at significantly higher risk for implant failure and greater marginal bone loss as compared with periodontally healthy subjects. Prospective observational studies with subject‐based designs are recommended.
Immediate Provisionalization of NanoTite Implants in Support of Single‐Tooth and Unilateral Restorations: One‐Year Interim Report of a Prospective, Multicenter Study
Authors: Östman Pär‐Olov , Hupalo Markijan , Del Castillo Robert , Emery Robert W. , Cocchetto Roberto , Vincenzi Giampaolo , Wagenberg Barry , Vanassche Bruno , Valentin Andreas , Clausen Gerard , Hogan Paul , Goené Ronnie , Evans Christopher , Testori Tiziano
Published: May 2009

Background: Clinical studies reporting immediate loading of endosseous implants for edentulous cases and for fixed partial restorations have been well documented with satisfactory survival rates. Implants with a recently developed, nanometer‐scale surface topography (NanoTite®, BIOMET 3i, Palm Beach Gardens, FL, USA), created by discrete crystalline depositions (DCD) of calcium phosphate nano‐crystals onto a dual acid‐etched (DAE) surface, show enhanced early fixation in preclinical studies when compared with DAE‐surfaced implants. These outcomes suggest DCD‐surfaced implants may be advantageous for immediate loading approaches.

Objective: The aim of this prospective, multicenter, observational study is to report clinical outcomes for DCD‐surfaced implants placed in immediate functional support of single‐ and multi‐unit restorations according to an immediate loading protocol.

Materials and Methods: One hundred eighty‐five patients enrolled at 15 international study centers received a total of 335 implants supporting 216 immediate provisionalizations consisting of 128 single‐tooth restorations and 88 fixed restorations. Of the 335 implants, 77% are located in posterior and 23% in anterior regions with 55.5% of the total in mandibles and 44.5% in maxillae. Patients were evaluated for implant mobility, gingival health, symptomatology, and radiographic outcomes.

Results: At the time of this 1‐year interim report, a total of 17 failures have been observed in 11 patients, yielding a cumulative survival rate of 94.9%.

Conclusion: Relative to other prospective, multicenter studies of immediately loaded implants with various surface enhancements, NanoTite implants perform comparatively well when immediately provisionalized with single‐tooth and fixed restorations.
A Comparison Study of the Osseointegration of Zirconia and Titanium Dental Implants. A Biomechanical Evaluation in the Maxilla of Pigs
Authors: Gahlert Michael , Röhling Stefan , Wieland Marco , Eichhorn Stefan , Küchenhoff Helmut , Kniha Heinz
Published: May 2009

Objectives: The purpose of the present study was to investigate the osseointegration of microstructured zirconia implants in comparison with sandblasted and acid‐etched (SLA) titanium implants in a biomechanical study.

Materials: Zirconia implants (4.1 mm in diameter, 10 mm in length) were produced using a new low pressure injection molding technique. After that the implants were acid‐etched with hydrofluoric acid. Standard Ti‐SLA implants of the exact same shape served as controls. Six months after extraction of incisors 2 and 3, 16 adult pigs received a total of 64 implants in the maxillae. After 4, 8, and 12 weeks the animals were sacrificed, and 59 implants could be analyzed to removal torque (RTQ) testing.

Results: The mean RTQ values for zirconia implants were 42.4 Ncm at 4 weeks, 69.6 Ncm at 8 weeks, and 69.3 Ncm at 12 weeks of healing, whereas RTQ values for the Ti‐SLA implants were 42.1 Ncm, 75.0 Ncm, and 73.1 Ncm at corresponding time intervals. There is no statistical difference in RTQ values between Ti‐SLA and zirconia implants at 8 weeks.

Conclusions: Within the limits of the present study it was concluded that acid‐etching of zirconia implants enhances bone apposition resulting in RTQ values which were equivalent to that of Ti‐SLA.
Assessment of Maxillary Sinus Septa Using Cone‐Beam Computed Tomography: Etiological Consideration
Authors: Naitoh Munetaka , Suenaga Yutaka , Kondo Shintaro , Gotoh Kenichi , Ariji Eiichiro
Published: May 2009

Background: Septum presence in the maxillary sinus complicates sinus floor elevation surgery, and so it is important that septa are accurately diagnosed on preoperative imaging.

Purpose: Septa were observed regarding their relationship with the bony palate using cone‐beam computed tomography (CT).

Materials and Methods: Thirty maxillary sinuses with dentate jaws of 15 dry skulls and a cone‐beam CT unit were used. A septum was defined as a pointed bone structure, and an exostosis was defined as a rounded bone structure. The occurrence and locations of maxillary sinus septa and exostoses of more than 2 mm in height were evaluated. Also, angles between the direction of septum and median palatine suture were measured on axial images.

Results: Twelve septa of 11 maxillary sinuses (37%) and nine exostoses of nine maxillary sinuses (30%) were observed. Also, 42% of septa and 67% of exostoses were antero‐posteriorly aligned according to the transverse palatine suture. Moreover, the mean septum angle was 57.9 degrees in the anterior maxillary sinus region, and 101.8 degrees in the transverse palatine suture region, and significant differences were noted between them.

Conclusion: Maxillary sinus septa and exostoses could be clarified regarding their relationship with the bony palate using cone‐beam CT.
A CONCEPTUAL AND EMPIRICAL REEXAMINATION OF THE MEASUREMENT OF THE SOCIAL DESIRABILITY OF ITEMS: IMPLICATIONS FOR DETECTING DESIRABLE RESPONSE STYLE AND SCALE DEVELOPMENT
Authors: KUNCEL NATHAN R , TELLEGEN AUKE
Published: May 2009

This paper calls into question traditional methods of measuring the social desirability of items and their use in scale construction. First, we make explicit that the proper focus for desirability studies of items and traits are the rated desirabilities of the alternative item responses indicating different trait levels. Second, the results from our first study show that the relation between degree of endorsement of an item and its judged desirability level is often nonlinear and varies across items such that no general model of item desirability can be adopted that will accurately represent the relations across all items, traits, and trait levels. In addition, the nature of these relationships can vary depending on whether desirability is considered in a work or general context. Third, results from a second study indicate specifically that people when instructed to self‐present in a maximally desirable manner will choose for some attributes a moderate level of endorsement (e.g., “agree”) rather than a more extreme response option (e.g., “strongly agree”). Subjects offer several different reasons for viewing the less extreme response options, which yield more moderate trait level scores, as more desirable. These reasons are linked to perceptions of the more extreme response option as being associated with negative behaviors and concerns about how others will view a more extreme response to the item. Both studies indicate that desirable responding to personality items is more complex than previously believed.
A SITUATIONAL JUDGMENT TEST OF PERSONAL INITIATIVE AND ITS RELATIONSHIP TO PERFORMANCE
Authors: BLEDOW RONALD , FRESE MICHAEL
Published: May 2009

Although situational judgment tests have been found to be valid predictors of performance, they have rarely been used to measure particular constructs. In this study, we apply the situational judgment test method to the measurement of personal initiative, a construct defined as situated action. We used respondents' situated preferences in mental simulations of work scenarios as formative indicators of their overall level of personal initiative at work. Results from a validation study showed that the situational judgment test of personal initiative (SJT‐PI) had adequate validity and complemented a Likert‐type self‐report measure of personal initiative in predicting behavioral criteria. Situated preferences for personal initiative were hypothesized to be proximal predictors of actual behavior and were accordingly found to mediate the relationship between generalized self‐efficacy, felt responsibility, and actual behavior. Furthermore, situated preferences for personal initiative could be differentiated empirically from organizational citizenship behavior. We conclude that situational judgment tests are a promising method for measuring personal initiative and may be a general means of improving the validity of measurement in organizations.
Convenient Synthesis of Ibuprofen and Naproxen Aminoacyl, Dipeptidoyl and Ester Derivatives
Authors: Katritzky Alan R. , Jishkariani Davit , Narindoshvili Tamari
Published: May 2009

dl‐Ibuprofen and l‐naproxen were coupled with amino acids and other bioactive compounds to provide ibuprofen and naproxen bioconjugates in 61–95% yield as prodrugs or potential drug candidates.
Synthesis and Biological Evaluation of Mercapto Triazolo‐Benzothiadiazine Linked Aminobenzothiazoles as Potential Anticancer Agents
Authors: Kamal Ahmed , Khan Mohammed Naseer A. , Srikanth Yellamelli V. V. , Rajesh Shetti V. C. R. N. C.
Published: May 2009

The synthesis of a series of 10‐substituted 5,5‐dioxo‐5,10‐dihydro[1,2,4]triazolo[4,3‐b][1,2,4]benzothiadiazine coupled with sulfanylacetamido benzothiazole pharmacophores (5a–g) is described. All the synthesized compounds have been evaluated for their anticancer activity. Most of the compounds showed significant growth inhibitory activity against selected human tumor cell lines. Interestinlgy, one of the synthesized compounds 5d, exhibited GI50 values of 1.4 and 2.1 μm against RPMI‐8226 (leukemia) and HOP‐62 (lungs) cell lines, respectively.
A High‐Content, Cell‐Based Screen Identifies Micropolyin, A New Inhibitor of Microtubule Dynamics
Authors: De Rycker Manu , Rigoreau Laurent , Dowding Sarah , Parker Peter J.
Published: May 2009

High‐content cell‐based screens provide a powerful tool to identify new chemicals that interfere with complex biological processes. Here, we describe the identification of a new inhibitor of microtubule dynamics (micropolyin) using a high‐content screen. Integrated high‐resolution imaging allowed for fast selection of hits and progression to target identification. Treatment of cells with micropolyin efficiently causes a pro‐metaphase arrest, with abnormal spindle morphology and with the spindle assembly checkpoint activated. The arrest appears to result from interference of micropolyin with microtubule dynamics. We show in vitro that tubulin is indeed the target of micropolyin and that micropolyin inhibits microtubule polymerization. Our results demonstrate the power of high‐content image‐ and cell‐based screening approaches to identify potential new drug candidates. As our approach is unbiased, it should allow for discovery of new targets that may otherwise be overlooked.
Design, Synthesis and Antifungal Activity of a Series of Novel Analogs Based on Diphenyl Ketones
Authors: Liu Wei , Shi Hui‐Min , Jin Hong , Zhao Hao‐Yu , Zhou Guo‐Ping , Wen Fang , Yu Zhi‐Yi , Hou Tai‐Ping
Published: May 2009

To find potent fungicides, 35 analogs of diphenyl ketones were synthesized and evaluated for their antifungal activity. These compounds possessed a furyl–carbonyl–phenyl skeleton. Bioassay results showed that the synthesized compounds were effective in promoting the antifungal activity of diphenyl ketones. Compound 3 showed the best activity against the four tested fungi (100%, 100%, 100% and 96.4%) and could be used as potent fungicide for further research.
Children's Geographies/Geographies of Children: Play, Work, Mobilities and Migration
Authors: Skelton Tracey
Published: May 2009

Geographers play an important role in expanding our understanding of children's lives, socio‐spatial identities and material practices. As a sub‐discipline, Children's Geographies is experiencing exponential growth throughout the wider discipline of geography. There has been a tendency to corral Children's Geographies into special issues of journals and several of these are reviewed below. However, this article specifically draws upon geographical work cited in many places of the discipline and also highlights work from an extremely wide range of geographies across the globe. This paper provides a review of geographers’ investigations into a very well‐established theme of social science research connected with children, that of play. It considers the spatialities and geographies of children's play (and its counterpoint, work), playing and spaces for play. It also examines the newer and emerging themes of mobilities, children's use of outdoor, public spaces collectively grouped under the term ‘street’, and the role of children in migration and of migration in children's lives. Throughout it considers possibilities for future research with children.
Inverse Method to Estimate Kinetic Degradation Parameters of Grape Anthocyanins in Wheat Flour Under Simultaneously Changing Temperature and Moisture
Authors: Lai K.P.K. , Dolan K.D. , Ng P.K.W.
Published: May 2009

ABSTRACT:  Thermal and moisture effects on grape anthocyanin degradation were investigated using solid media to simulate processing at temperatures above 100 °C. Grape pomace (anthocyanin source) mixed with wheat pastry flour (1: 3, w/w dry basis) was used in both isothermal and nonisothermal experiments by heating the same mixture at 43% (db) initial moisture in steel cells in an oil bath at 80, 105, and 145 °C. To determine the effect of moisture on anthocyanin degradation, the grape pomace–wheat flour mixture was heated isothermally at 80 °C at constant moisture contents of 10%, 20%, and 43% (db). Anthocyanin degradation followed a pseudo first‐order reaction with moisture. Anthocyanins degraded more rapidly with increasing temperature and moisture. The effects of temperature and moisture on the rate constant were modeled according to the Arrhenius and an exponential relationship, respectively. The nonisothermal reaction rate constant and activation energy (mean ± standard error) were k80 °C, 43% (db) moisture = 2.81 × 10−4± 1.1 × 10−6 s−1 and ΔE = 75273 ± 197 J/g mol, respectively. The moisture parameter for the exponential model was 4.28 (dry basis moisture content)−1. One possible application of this study is as a tool to predict the loss of anthocyanins in nutraceutical products containing grape pomace. For example, if the process temperature history and moisture history in an extruded snack fortified with grape pomace is known, the percentage anthocyanin loss can be predicted.
Real‐time PCR quantification of haematopoietic chimerism after transplantation: a comparison between TaqMan and hybridization probes technologies
Authors: MARTINEZ‐LOPEZ J. , CROOKE A. , GRANDE S. , AYALA R. , JIMÉNEZ‐VELASCO A. , GAMARRA S. , MENEU J. C. , GILSANZ F.
Published: May 2009

This study aimed to compare the sensitivity and accuracy of two methods of quantitative real‐time polymerase chain reaction (qrt‐PCR), in order to determine haematopoietic chimerism (CH): single nucleotide polymorphisms using TaqMan (TM) probes and insertion/deletion polymorphisms using Hybridization (Hyb) probes. A total of 106 samples from 20 patients who underwent allogenic stem cell transplantation (n = 14) or live‐donor liver transplantation (n = 6) were studied. The mean level of chimerism was 8.37% for the TM method and 7.73% in the Hyb method, which was not significantly different (P = 0.69). The Pearson correlation coefficient between the two methods was r = 0.91 (P < 0.001). The estimation of the regression line, using the Passing and Balbock method was Intercept A −0.0381 [95% confidence interval (CI) −0.1265 to 0.0296) and Slope B: 1.04609(95% CI 0.9349–1.161). Bland–Altman data showed that the standard deviations, which differed between the two methods (%Hyb–%TM), were 0.98 and −1.28. The accuracy and sensitivity of qrt‐PCR chimerism is independent of the method used if the optimization is adequate and satisfies the criteria for adequate study. Real‐time PCR, independent of the method adopted, is a very good tool for study levels of CH.
Schooling the Cognitive Monster: The Role of Motivation in the Regulation and Control of Prejudice
Authors: Monteith Margo J. , Lybarger Jill E. , Woodcock Anna
Published: May 2009

Motivation has been a central construct in theoretical and empirical efforts to understand the nature of prejudice and stereotyping. We briefly review core motivational underpinnings of prejudice and stereotyping, focusing on aspects of the human condition that help to explain why we are so prone to bias. The strong propensity toward stereotyping and prejudice along with the automatic manner in which intergroup biases often operate have led researchers to question the controllability of such biases (e.g., Bargh's (1999) characterization of stereotyping as a ‘cognitive monster’ that could not be ‘chained’ through efforts at control). We revisit the issue of the controllability of stereotyping and prejudice in light of recent work examining the effects of motivations to control prejudice on regulatory processes. Although a top‐down approach to regulation has been emphasized in much past work (e.g., the conscious replacement of prejudiced associations with more egalitarian thoughts), there is growing evidence that more automated and less effortful bottom‐up regulation is also possible (i.e., a ‘schooling’ of the ‘cognitive monster’). Altogether, the accumulated evidence points to the limitations of dual‐process approaches when applied to understanding the control and regulation of prejudiced responses. The evidence argues instead for a more complex, dynamic, and multi‐level conceptualization of regulation.
From Antiracism to Antiracisms
Authors: O’Brien Eileen
Published: May 2009

Although antiracism has existed as long as there has been racism, social scientists’ attention to antiracism has increased in the past decade. In this essay, I argue that the body of scholarship on antiracism is characterized by three main strands: (1) a macro focus on the ideology and structure of antiracist social movement organizations, often attempting to distil ‘the real’ antiracism from others deemed not critical or radical enough to qualify; (2) a micro focus on what motivates individuals to become antiracist, usually concentrating more on whites and using an a priori assumption that people of colour are automatic antiracists; and (3) a more promising interest in the antiracisms of the racial middle (Latinos, Asians, multiracials). This latter focus is emerging with a handful of scholars largely outside the United States, questioning the assumptions of the previous two strands, and offering interesting potential for the future of the field.
Myocardial metabolism of triacylglycerol‐rich lipoproteins in type 2 diabetes
Authors: Niu You‐Guo , Evans Rhys D.
Published: May 2009

Cardiac utilisation of very‐low‐density lipoprotein (VLDL) and chylomicrons (CM) was investigated in the ZDF rat model of type 2 diabetes, in order to define the role of triacylglycerol (TAG) metabolism in the development of contractile dysfunction. Hearts from obese diabetic and lean littermate control rats were perfused with VLDL and CM from diabetic and control rats. Metabolic fate of the lipoprotein TAG and contractile function were examined. Myocardial utilisation of both VLDL‐ and CM‐TAG was increased in the diabetic state. Diabetic hearts oxidised diabetic lipoprotein‐TAG to a greater extent than control lipoproteins; glucose oxidation was decreased. There was no difference in lipoprotein‐TAG assimilation into diabetic heart lipids; diabetic lipoproteins were, however, a poor substrate for control heart tissue lipid accumulation. Although the proportion of exogenous lipid incorporated into tissue TAG was increased in diabetic hearts perfused with control lipoproteins, this effect was not seen in diabetic hearts perfused with diabetic lipoproteins. Myocardial heparin‐releasable lipoprotein lipase (LPL) activity was moderately increased in the diabetic state, and diabetic lipoproteins increased tissue‐residual LPL activity. Cardiac hydraulic work was decreased only in diabetic hearts perfused with diabetic CM. Compositional analysis of diabetic variant lipoproteins indicated changes in size and apoprotein content. Alterations in cardiac TAG‐rich lipoprotein metabolism in type 2 diabetes are due to changes in both the diabetic myocardium and the diabetic lipoprotein particle; decreased contractile function is not related to cardiac lipid accumulation from TAG‐rich lipoproteins but may be associated with changes in TAG‐fatty acid oxidation.
Determination of Cellular Tractions on Elastic Substrate Based on an Integral Boussinesq Solution
Authors: Huang Jianyong , Peng Xiaoling , Qin Lei , Zhu Tao , Xiong Chunyang , Zhang Youyi , Fang Jing
Published: May 2009

Cell-substrate interaction is implicated in many physiological processes. Dynamical monitoring of cellular tractions on substrate is critical in investigating a variety of cell functions such as contraction, migration, and invasion. On account of the inherent ill-posed property as an inverse problem, cellular traction recovery is essentially sensitive to substrate displacement noise and thus likely produces unstable results. Therefore, some additional constraints must be applied to obtain a reliable traction estimate. By integrating the classical Boussinesq solution over a small rectangular area element, we obtain a new analytical solution to express the relation between tangential tractions and induced substrate displacements, and then form an alternative discrete Green’s function matrix to set up a new framework of cellular force reconstruction. Deformation images of flexible substrate actuated by a single cardiac myocyte are processed by digital image correlation technique and the displacement data are sampled with a regular mesh to obtain cellular tractions by the proposed solution. Numerical simulations indicate that the 2-norm condition number of the improved coefficient matrix typically does not exceed the order of 100 for actual computation of traction recovery, and that the traction reconstruction is less sensitive to the shift or subdivision of the data sampling grid. The noise amplification arising from ill-posed inverse problem can be restrained and the stability of inverse solution is improved so that regularization operations become less relevant to the present force reconstruction with economical sampling density. The traction recovery for a single cardiac myocyte, which is in good agreement with that obtained by the Fourier transform traction cytometry, demonstrates the feasibility of the proposed method. We have developed a simple and efficient method to recover cellular traction field from substrate deformation. Unlike previous force reconstructions that numerically employ some regularization schemes, the present approach stabilizes the traction recovery by analytically improving the Green’s function such that the intricate regularizations can be avoided under proper conditions. The method has potential application to a real-time traction force microscopy in combination with a high-efficiency displacement acquisition technique.
Measurement of Young’s Modulus of Human Tympanic Membrane at High Strain Rates
Authors: Luo Huiyang , Dai Chenkai , Gan Rong Z. , Lu Hongbing
Published: May 2009

The mechanical behavior of human tympanic membrane (TM) has been investigated extensively under quasistatic loading conditions in the past. The results, however, are sparse for the mechanical properties (e.g., Young's modulus) of the TM at high strain rates, which are critical input for modeling the mechanical response under blast wave. The property data at high strain rates can also potentially be converted into complex modulus in frequency domain to model acoustic transmission in the human ear. In this study, we developed a new miniature split Hopkinson tension bar to investigate the mechanical behavior of human TM at high strain rates so that a force of up to half of a newton can be measured accurately under dynamic loading conditions. Young’s modulus of a normal human TM is reported as 45.2–58.9 MPa in the radial direction, and 34.1–56.8 MPa in the circumferential direction at strain rates 300–2000 s−1. The results indicate that Young’s modulus has a strong dependence on strain rate at these high strain rates.
Simulating Acceleration From Stereophotogrammetry For Medical Device Design
Authors: Tresadern Philip A. , Thies Sibylle B. , Kenney Laurence P. J. , Howard David , Smith Christine , Rigby Julie , Goulermas John Y.
Published: May 2009

When designing a medical device based on lightweight accelerometers, the designer is faced with a number of questions in order to maximize performance while minimizing cost and complexity: Where should the inertial unit be located? How many units are required? How is performance affected if the unit is not correctly located during donning? One way to answer these questions is to use position data from a single trial, captured with a nonportable measurement system (e.g., stereophotogrammetry) to simulate measurements from multiple accelerometers at different locations on the body. In this paper, we undertake a thorough investigation into the applicability of these simulated acceleration signals via a series of interdependent experiments of increasing generality. We measured the dynamics of a reference coordinate frame using stereophotogrammetry over a number of trials. These dynamics were then used to simulate several “virtual” accelerometers at different points on the body segment. We then compared the simulated signals with those directly measured to evaluate the error under a number of conditions. Finally, we demonstrated an example of how simulated signals can be employed in a system design application. In the best case, we may expect an error of 0.028 m/s2 between a derived virtual signal and that directly measured by an accelerometer. In practice, however, using centripetal and tangential acceleration terms (that are poorly estimated) results in an error that is an order of magnitude greater than the baseline. Furthermore, nonrigidity of the limb can increase error dramatically, although the effects can be reduced considerably via careful modeling. We conclude that using simulated signals has definite benefits when an appropriate model of the body segment is applied.
Stress Relaxation Behavior of Mandibular Condylar Cartilage Under High-Strain Compression
Authors: Singh M. , Detamore M. S.
Published: May 2009

During temporomandibular joint (TMJ) function, the mandibular condylar cartilage plays a prime role in the distribution and absorption of stresses generated over the condyle. Biomechanical characterization of the tissue under compression, however, is still incomplete. The present study investigates the regional variations in the elastic and equilibrium moduli of the condylar cartilage under high strains using unconfined compression and stress relaxation, with aims to facilitate future tissue engineering studies. Porcine condylar cartilages from five regions (anterior, central, lateral, medial, and posterior) were tested under unconfined compression. Elastic moduli were obtained from the linear regions of the stress-strain curves corresponding to the continuous deformation. Equilibrium moduli were obtained from the stress relaxation curves using the Kelvin model. The posterior region was the stiffest, followed by the middle (medial, central, and lateral) regions and the anterior region, respectively. Specifically, in terms of the equilibrium modulus, the posterior region was 1.4 times stiffer than the middle regions, which were in turn 1.7 times stiffer than the anterior region, although only the difference between anterior and posterior regions was statistically significant. No significant differences in stiffness were observed among the medial, central, lateral, and posterior regions. A positive correlation between the thickness and stiffness of the cartilage was observed, reflecting that their regional variations may be related phenomena caused in response to cartilage loading patterns. Condylar cartilage was less stiff under compression than in tension. In addition, condylar cartilage under compression appears to behave in a manner similar to the TMJ disc in terms of the magnitude of moduli and drastic initial drop in stress after a ramp strain.
Whole Bone Strain Quantification by Image Registration: A Validation Study
Authors: Hardisty Michael R. , Whyne Cari M.
Published: May 2009

Quantification of bone strain can be used to better understand fracture risk, bone healing, and bone turnover. The objective of this work was to develop and validate an intensity matching image registration method to accurately measure and spatially resolve strain in vertebrae using μCT imaging. A strain quantification method was developed that used two sequential μCT scans, taken in loaded and unloaded configurations. The image correlation algorithm implemented was a multiresolution intensity matching deformable registration that found a series of affine mapping between the unloaded and loaded scans. Once the registration was completed, the displacement field and strain field were calculated from the mappings obtained. Validation was done in two distinct ways: the first was to look at how well the method could quantify zero strain; the second was to look at how the method was able to reproduce a known applied strain field. Analytically defined strain fields that linearly varied in space and strain fields resulting from finite element analysis were used to test the strain measurement algorithm. The deformable registration method showed very good agreement with all cases imposed, establishing a detection limit of 0.0004 strain and displaying agreement with the imposed strain cases (average R2=0.96). The deformable registration routine developed was able to accurately measure both strain and displacement fields in whole rat vertebrae. A rigorous validation of any strain measurement method is needed that reports on the ability of the routine to measure strain in a variety of strain fields with differing spatial extents, within the structure of interest.