bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel GABAA receptor pharmacology: drugs interacting with the α+β‐ interface
Authors: Sieghart Werner , Ramerstorfer Joachim , Sarto‐Jackson Isabella , Varagic Zdravko , Ernst Margot
Published: November 2011

GABAA receptors are ligand‐gated chloride channels composed of five subunits that can belong to different subunit classes. The existence of 19 different subunits gives rise to a multiplicity of GABAA receptor subtypes with distinct subunit composition; regional, cellular and subcellular distribution; and pharmacology. Most of these receptors are composed of two α, two β and one γ2 subunits. GABAA receptors are the site of action of a variety of pharmacologically and clinically important drugs, such as benzodiazepines, barbiturates, neuroactive steroids, anaesthetics and convulsants. Whereas GABA acts at the two extracellular β+α‐ interfaces of GABAA receptors, the allosteric modulatory benzodiazepines interact with the extracellular α+γ2‐ interface. In contrast, barbiturates, neuroactive steroids and anaesthetics seem to interact with solvent accessible pockets in the transmembrane domain. Several benzodiazepine site ligands have been identified that selectively interact with GABAA receptor subtypes containing α2βγ2, α3βγ2 or α5βγ2 subunits. This indicates that the different α subunit types present in these receptors convey sufficient structural differences to the benzodiazepine binding site to allow specific interaction with certain benzodiazepine site ligands. Recently, a novel drug binding site was identified at the α+β‐ interface. This binding site is homologous to the benzodiazepine binding site at the α+γ2‐ interface and is thus also strongly influenced by the type of α subunit present in the receptor. Drugs interacting with this binding site cannot directly activate but only allosterically modulate GABAA receptors. The possible importance of such drugs addressing a spectrum of receptor subtypes completely different from that of benzodiazepines is discussed.
Effects of immediate or delayed addition of platelet additive solution on the in vitro quality of apheresis platelets
Authors: Ringwald Juergen , Tully Susanne , Geier Christoph , Hauck Barbara , Weiss Dominik , Callaert Martine , Eckstein Reinhold
Published: November 2011

BACKGROUND: There is little knowledge how different hold times of hyperconcentrated platelet (PLT) suspensions (HPSs) before the addition of platelet additive solution (PAS) might affect PLT quality. We compared the in vitro quality of single‐donor PLT concentrates (SDPs) with immediate or delayed PAS addition and studied the quality of collected concurrent plasma (CP).

STUDY DESIGN AND METHODS: We collected 6 × 1011 PLTs in 175 of mL plasma and CP from 31 donors. The HPSs were split into two parts, with 162 mL of modified PAS III (PAS‐IIIM) added immediately (0hr‐SDP) or 2 hours later (2hr‐SDP). Final SDPs had a targeted concentration of 1.2 × 1012 PLTs/L and a PAS proportion of 65%. On Days 1, 5, and 7 we determined glucose and lactate concentration, pH, P‐selectin expression, hypotonic shock response (HSR), and extent of shape change (ESC). Clotting Factor V (FV) and VIII (FVIII) activities and D‐dimer concentration were determined in CP and donor.

RESULTS: Glucose utilization, lactate production, and pH were similar for both kinds of products. Low P‐selectin expression indicated no relevant PLT activation during storage. HSR and ESC were similarly well preserved. Recoveries of FV and FVIII were 100.0 ± 14.0 and 98.6 ± 14.9%, respectively. Concentrations of D‐dimers in the donor and CP were 173.7 ± 90.1 and 177.6 ± 91.2 ng/dL, respectively.

CONCLUSIONS: Adding PAS immediately or 2 hours after collection does not result in different in vitro quality of PLTs stored up to 7 days. The good recovery of clotting factors with no signs of activation indicates a good quality of CP.
Depression Screening During Pregnancy
Authors: Breedlove Ginger , Fryzelka Denise
Published: November 2011

Depression in the antepartum period is more commonly missed by clinicians than is intimate partner violence, although more women and families suffer from this debilitating disease. Early identification and appropriate psychotherapeutic interventions significantly reduce the risk of adverse effects for the mother, infant, and family. Despite debate regarding specificity and sensitivity, 2 instruments have been predominantly referenced for use in antepartum screening: the Edinburgh Postnatal Depression Scale and the Center for Epidemiologic Studies Depression Scale. Routine screening combined with interview methods provides high reliability for predicting a risk for depression in pregnancy and postpartum. Caution should be exercised when new onset is identified or when women who were using psychotropic medications before pregnancy are being treated, because the relative risk of prenatal exposure to medication is counterbalanced by the risk of relapse of maternal psychiatric disorders.
My Baby, My Move: Examination of Perceived Barriers and Motivating Factors Related to Antenatal Physical Activity
Authors: Leiferman Jenn , Swibas Tracy , Koiness Kacey , Marshall Julie A. , Dunn Andrea L.
Published: November 2011

Introduction:Based on a socioecological model, the present study examined multilevel barriers and facilitators related to physical activity engagement during pregnancy in women of low socioeconomic status.

Methods:Individual and paired interviews were conducted with 25 pregnant women (aged 18‐46 years, 17‐40 weeks’ gestation) to ask about motivational factors and to compare differences in activity level and parity. Atlas/Ti software was used to code verbatim interview transcripts by organizing codes into categories that reflect symbolic domains of meaning, relational patterns, and overarching themes.

Results:Perceived barriers and motivating factors differed between exercisers and nonexercisers at intrapersonal, interpersonal, and environmental levels.

Discussion:Future interventions should take into account key motivating multilevel factors and barriers to tailor more meaningful advice for pregnant women.
Maternal Temperature Elevation and Occiput Posterior Position at Birth Among Low‐Risk Women Receiving Epidural Analgesia
Authors: Osborne Cara , Ecker Jeffrey L. , Gauvreau Kimberlee , Davidson Karen M. , Lieberman Ellice
Published: November 2011

Introduction: To evaluate the relationship between maternal temperature elevation and occiput posterior position at birth as well as the association of fetal head position and temperature elevation on method of birth among women receiving epidural analgesia.

Methods: We conducted a secondary analysis of data from the Fetal Orientation during Childbirth by Ultrasound Study (FOCUS), which used serial ultrasounds to evaluate the effect of epidural anesthesia on fetal position at birth in low‐risk women. The current analysis was limited to the 1428 study participants who received epidural analgesia.

Results: In our population, 47% (n = 669) of women had a maximum intrapartum temperature greater than or equal to 99.6°F (37.6°C). The prevalence of fetal occiput posterior position at admission did not differ between women who later developed temperature elevations (24.4%) and those who did not (23.6%, P= .70). Women who developed an elevated temperature greater than or equal to 99.6°F (37.6°C) had an increased risk of occiput posterior fetal head position at birth regardless of the amount of temperature elevation (odds ratio [OR]= 2.0; 95% confidence interval [CI], 1.5‐2.8); the association persisted after control for potentially confounding factors (adjusted OR = 1.5; 95% CI, 1.1‐2.1). The cesarean birth rate among women with both temperature elevation and occiput posterior position at birth was more than 12 times the rate of women with neither risk factor (adjusted OR = 12.6; 95% CI, 7.5‐21.2).

Discussion: Intrapartum temperature elevation among women receiving epidural analgesia, even if only to 99.6°F (37.6°C), is associated with approximately a 2‐fold increase in the occurrence of occiput posterior fetal head position at birth. Additionally, although this observational study cannot establish causal links, our findings suggest that the relationship between epidural‐related intrapartum temperature elevation and occiput posterior position at birth could contribute to an increased cesarean birth rate among women receiving epidural analgesia for pain relief in labor.
A Girl Thing: Perceptions Concerning the Word “Hymen” Among Young Swedish Women and Men
Authors: Christianson Monica , Eriksson Carola
Published: November 2011

Introduction: This study investigated, from a gender perspective, perceptions concerning the word “hymen” among students in a Swedish senior high school.

Methods: Students answered an open‐ended question: What do you think about when you hear the word hymen? The answers were analyzed by using content analysis.

Results: In total, 198 students, aged 17 to 18 years, answered the question. The theme “a fragile biological structure in the female body” described how the vast majority of the girls and 57% of the boys associated the hymen with a thin membrane that breaks during first vaginal intercourse. The theme “a symbol and manifestation of feminine virginity” described the symbolic meanings of having or not having a hymen. The theme “questioning the existence of the hymen” revealed the doubts that some had about its existence.

Discussion: Most of the students associated the hymen with a breakable membrane. This is problematic. It may lead to misunderstandings about virginity or about bleeding during sexual intercourse. Changing these views about the hymen is important to correct such misunderstanding but may be a significant challenge. In modern medical discourse, in health care, and in popular speech, there are few discussions about the hymen as a social construct, indicating that more gender research concerning hymen‐related issues is needed.
Defining Male Support During and After Pregnancy From the Perspective of HIV‐Positive and HIV‐Negative Women in Durban, South Africa
Authors: Maman Suzanne , Moodley Dhayendre , Groves Allison K.
Published: November 2011

Introduction: Greater male support during pregnancy and in the postpartum period may improve health outcomes for mothers and children. To develop effective strategies to engage men, we need to first understand the ways that men are currently engaged and the barriers to their greater involvement.

Methods: We conducted in‐depth interviews in isiZulu with 30 HIV‐positive women and 16 HIV‐negative women who received prenatal care from a public clinic in Durban, South Africa. Interviews were audiotaped, transcribed, translated, and coded for analysis.

Results: Although less than a quarter of women reported that their partners accompanied them to the clinic, they described receiving other material and psychosocial support from partners. More HIV‐positive women reported that their partners were not involved or not supportive, and in some cases direct threats and experiences with violence caused them to fear partner involvement.

Discussion: We need to broaden the lens through which we consider male support during pregnancy and in the postpartum period and acknowledge that male involvement may not always be in the best interest of women. Engaging supportive partners outside of the clinic setting and incorporating other important social network members are important next steps in the effort to increase support for women.
Validation of an Online Data Registry for Midwifery Practices: A Pilot Project
Authors: Stapleton Susan Rutledge
Published: November 2011

Introduction: The value of a data registry for research, benchmarking, and quality improvement activities depends on the underlying quality of the data. This pilot study was conducted to design and implement a validation process assessing data quality in the American Association of Birth Centers’ online data registry, the Uniform Data Set (UDS).

Methods: Site visits were conducted in 5 midwifery practices attending births in freestanding birth centers and hospitals to compare data from health records with data in the registry. Practices meeting the inclusion criteria and representative of the overall population of midwifery practices contributing data to the UDS were audited. Between 2% and 5% of each practice's total UDS records were randomly selected and then compared with their matched health records for 29 key variables from the 189 variables in the UDS.

Results: A total of 3966 variables were reviewed for 152 records. There were 126 records for which complete maternity care was provided; thus, all 4 parts of the UDS were expected. There were 26 records for women who left care during pregnancy; thus, only parts 1 and 2 of the UDS were expected. Quality of the UDS data was evaluated, with the health records serving as the criterion standard, and the 2 sources were found to be consistent for 97.1% of the variables.

Discussion: Results from the study suggest that the data registry can provide valid data for use in research describing the process and outcomes of midwifery care and for benchmarking and quality improvement activities.
Differences in Women's Psychological Well‐being Based on Infertility Treatment Choice and Outcome
Authors: McCarthy M. Patrice , Chiu Sheau‐Huey
Published: November 2011

Introduction: The empirical foundation regarding women's experiences with infertility is influenced by the use of clinically based populations of women who are seeking medical assistance to conceive. Although the experience of infertility and involuntary childlessness is recognized as a significant life stressor characterized by a loss of control, bodily integrity, and identity, little is understood about women who perceive an infertility problem but do not seek treatment.

Methods: A secondary analysis was conducted by using a national probability sample from the National Survey of Fertility Barriers. Women (N = 142) who self‐reported perceptions of fertility problems were placed in 1 of 3 groups based on the decision to seek/not seek treatment and treatment outcome.

Results: When we controlled for marital status, women who conceived with medical assistance reported significantly higher levels of life satisfaction and held parenting as more important than women who sought treatment and did not conceive and women who did not seek treatment.

Discussion: Women who did not seek treatment for perceived infertility problems reported a decreased sense of the importance of parenthood but also reported lower levels of self‐esteem and life satisfaction than women who sought treatment, regardless of treatment outcome.
A Review of Systemic Opioids Commonly Used for Labor Pain Relief
Authors: Anderson Deborah
Published: November 2011

Parenteral opioids for pain relief during labor have been the subject of research for many decades. Commonly used systemic opioids provide limited pain relief during labor yet are used extensively for managing labor pain. These opioids share similar pharmacologic profiles but differ in potency, pharmacokinetics, and side effects. This article reviews the pharmacokinetics, pharmacodynamics, and clinical research related to the commonly used systemic labor pain analgesics morphine, meperidine, fentanyl, remifentanil, butorphanol, and nalbuphine.
Sexual Function and Quality of Life for Women with Mild‐to‐Moderate Stress Urinary Incontinence
Authors: Liebergall‐Wischnitzer Michal , Paltiel Ora , Hochner‐Celnikier Drorit , Lavy Yuval , Manor Orly , Woloski Wruble Anna Carol
Published: November 2011

Introduction: Sexual function is affected by stress urinary incontinence with or without pelvic organ prolapse. The aim of the study was to describe the sexual function of women with mild‐to‐moderate stress urinary incontinence, with or without pelvic organ prolapse (up to stage 2) and examine correlations with symptoms and quality of life. This investigation was part of a large, randomized, clinical trial of women with stress urinary incontinence who participated in an exercise intervention.

Methods: Women included in the study suffered from stress urinary incontinence as measured by a pad test and were interested in an exercise intervention. All participants underwent assessment for prolapse staging. Instruments included: the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ‐12), Incontinence Quality of Life Questionnaire (I‐QOL), and a health and urinary leakage questionnaire.

Results: One hundred and eighty‐seven ambulatory women, aged 20 to 65 years, had a mean sexual function score of 36.9 (standard deviation [SD] 5.9). No significant correlation was found between the sexual function scores and quantity of urinary leakage. A significant correlation existed between the sexual function and I‐QOL scores (P < .001). An additional finding was that women with urgency symptoms were older (P= .04) and had significantly lower sexual function scores (mean 35.7; SD 6.4) than those who did not report urgency (mean 38.7; SD 4.6; P < .001).

Discussion: Women with mild‐to‐moderate stress urinary incontinence, without or with lower stages of pelvic organ prolapse, demonstrated good sexual function, which correlated with physical and psychosocial factors. Health professionals need to perform multifaceted intake assessments on women with urinary leakage to customize their health promotion regimen.
PERCEPTIONS ON BIRTH POSITIONS AMONG MIDWIVES AND OBSTETRICIANS AT MALALAI MATERNITY HOSPITAL AND BADAKHSHAN PROVINCIAL HOSPITAL, AFGHANISTAN
Authors: Mushtari Feroza , Hamnawozada Saleha
Published: November 2011

Background: The choice of positions during labor and birth has a huge impact on a mother's comfort levels during the birth process and how quickly and effectively her labor does or does not progress. The aim of this study is to explore health care providers’ perceptions on birthing positions and the possibility to improve evidence‐based variety in birthing positions in 2 busy hospitals in Afghanistan. Methods: An exploratory study using focus group discussions (FGDs) asked 30 physicians and midwives in Malalai Maternity Hospital, Kabul, and Badakhshan Provincial Hospital in which positions women can labor and give birth. Convenience sampling technique was utilized to select health workers from 1 urban and 1 rural setting. Data collectors were midwives trained in conducting FGDs. Ethical approval was taken from Institution Review Board. Results: Providers’ perceptions include that some positions have disadvantages such as standing position is difficult to manage and may cause lacerations. They prefer that patients do not give birth in standing position regardless of the woman's wishes. They also think it is unhygienic to give birth in a “sitting/squatting position”. Conclusion: Health care provider perceptions significantly impact women's choices of position during birth and this may contribute to the decision to give birth at home. Researchers recommend educating health care providers and advocating that facilities offer alternative birthing positions and resources in hospitals. Hospital management should ensure that women are supported to adopt the position of their choice.
Identification of Gunshot Residues in Fabric Targets Using Sector Field Inductively Coupled Plasma Mass Spectrometry Technique and Ternary Graphs*
Authors: Freitas João Carlos D. , Sarkis Jorge E. Souza , Neto Osvaldo Negrini , Viebig Sônia Bocamino
Published: November 2011

Abstract: During criminal investigations involving firearms, the detection of gunshot residues (GSRs) is one of the most important evidences. In the present study, a new method to identify trace evidences of GSRs, deposited around the bullet entrance hole, in different types of fabrics used as targets, is described. The experiments were carried out using a 0.38‐inch caliber revolver, and 9‐mm and 0.40‐inch caliber pistols. Testimonies of 2.25 cm2of the fabrics were cut around the bullet entrance and digested with 10% nitric acid. Antimony, barium, and lead were analyzed in the remaining solution using a sector field inductively coupled plasma mass spectrometer. The concentrations of the elements were detected at levels up to few microgram per square centimeter. The use of ternary graphics allowed us to identify specific patterns of distribution for blank samples and the clear distinction between the revolver and pistols used.
Quantifying the structure of food demand in China: An econometric approach
Authors: Hovhannisyan Vardges , Gould Brian W.
Published: November 2011

This article examines food demand structure and its dynamics for 11 commodities in urban China. The analysis is based on household‐level expenditure survey data for two cross‐sectional surveys of Chinese households pertaining to food expenditure patterns during 1995 and 2003. Pre‐committed components of commodity demands, that are insensitive to economic variables, are explored.

We use the generalized quadratic almost ideal demand system (GQAIDS) for its empirical superiority to the generalized almost ideal demand system (GAIDS), and estimate the associated parameters via full information maximum likelihood procedure (FIML) accounting for endogeneity of total expenditures on food for home consumption (FAH). We also use quality‐adjusted commodity unit values to control for quality differences resulting from commodity aggregation and food choice. Furthermore, we derive GQAIDS elasticity formulas, and estimate income elasticities without restrictions.

The results partially support the hypothesis that an average Chinese household has incorporated elements of Western diet (fine grains) into traditional Chinese food diet over time. Moreover, the outcome of a simple test developed here points to possible preference changes for a majority of food staples under study.
Distress rentals and the land rental market as a safety net: contract choice evidence from Tigray, Ethiopia
Authors: Gebregziabher Gebrehaweria , Holden Stein T.
Published: November 2011

Rural households in the semiarid Northern Ethiopian highlands are net buyers of food. Crop failure due to erratic and unpredictable rainfall occurs frequently and leads to food shortages and income shocks. The renting out of land may be one of the coping responses of households exposed to shocks. We developed a theoretical household model for poor landlord households capturing their contract choice response to downside production shocks. We tested econometrically whether contract choice may depend on poverty, capital constraints, production risk and random shocks. The multinomial logit model estimates show that poor households experiencing random shocks are more likely to choose fixed‐rent contracts as a distress response to shocks, suggesting that fixed‐rent contracts may be used to meet immediate needs, but at the expense of future incomes. We also found that fixed‐rent contracts are preferred when ex ante production risk is low, while sharecropping is more likely where production risk is high. Finally, we found an indication that the choice of a fixed‐rent contract as a coping response to shocks comes as a last resort after all other means of coping are exhausted.
Impact of copula choice on the modeling of crop yield basis risk
Authors: Woodard Joshua D. , Paulson Nicholas D. , Vedenov Dmitry , Power Gabriel J.
Published: November 2011

A number of problems in agricultural economics involve modeling joint distributions for which the assumption of multivariate normality may not be warranted. Yet, very little work has been conducted evaluating competing methods for modeling joint dependence. We develop a simulation framework to evaluate the bias and efficiency impacts of copula choice in the context of evaluating county‐to‐farm basis risk. The results suggest significant differences in performance across various copulas and approaches. The findings have important implications for risk analysis, insurance, and policy modeling problems in agriculture regarding the selection of method to model dependence among random variables.
Measuring the cost of liquidity in agricultural futures markets: Conventional and Bayesian approaches
Authors: Frank Julieta , Garcia Philip
Published: November 2011

Estimating the cost of liquidity in agricultural futures markets is challenging because bid‐ask spreads are usually not observed. Based on an ability to reflect simulated data from Roll's spread model, we assess the effectiveness of conventional and Bayesian bid‐ask spread estimators under different market conditions. Conventional serial covariance and absolute price change spread estimators appear to be biased. Hasbrouck's Bayesian estimator generates small costs of liquidity whose values depend on the correlation and noise in the data. The absolute value Bayesian estimator is precise and works well under conditions of high levels of noise and correlation usually found in agricultural futures markets. Using data from live cattle (LC) and lean hog (LH) contracts, we find similar patterns of performance that produce economically meaningful cost of liquidity differences.
IL1 gene polymorphisms and unsuccessful dental implants
Authors: Vaz P. , Gallas M. M. , Braga A. C. , Sampaio‐Fernandes J. C. , Felino A. , Tavares P.
Published: November 2011

Objectives

This study aimed to analyse the association between polymorphisms in the IL1 gene cluster and failure of dental implants in a Portuguese population.

Material and methods

A total of 155 Caucasian Portuguese subjects were divided into two groups: 100 with successful dental implants and 55 with unsuccessful dental implants. DNA was obtained through an oral mucosa scraping. PCR was used to identify the polymorphisms: single nucleotide changes in positions −889 of IL1A gene and +3953 of IL1B gene.

Results

The prevalence of the polymorphisms −889IL1A gene and +3953IL1B gene, determined by the positive result of TGP (Genetic Test for Periodontitis; CGC, Genetics, Portugal), in the studied population rehabilitated with dental implants was of 33.50%. Allele 1 of the IL1B gene was the most prevalent (62.20%), followed by allele 1 of the IL1A gene (54.80%) and the least frequent was allele 2 of IL1B gene (37.40%). Success of dental implants was mainly associated with a negative TGP result, whereas no success was found to be related to a positive result. There were no statistically significant differences between the alleles 1 and 2 of the genes IL1A and IL1B and the tobacco and alcohol consumption for the success or no success of the dental implants.

Conclusions

The alleles 1 and 2 of IL1A gene and the alleles 1 and 2 of IL1B gene were statistically associated with the success or no success of the dental implants. Tobacco habit and alcohol consumption showed no statistically significant association with success or no success of the dental implants.
Cooperation and Prosperity of the Americas Initiative: Puerto Rico and Opportunities for Increased Partnership, Collaboration, and Stability for the People of the Americas
Authors: Figueroa Richard , Hagadorn Jason
Published: November 2011

The U.S. government's efforts to redefine policy toward Latin America, and to counter the image that it is doing little more than fighting drug trafficking, would be boosted if it embraced cooperation with its territory in the Caribbean: Puerto Rico. Despite years of disagreement and distrust between federal and Puerto Rican political leaders, it is time to refocus on how the island's developed infrastructure, educated population, demonstrated patriotism to the United States, and cultural affinity with Latin America can help U.S.–Latin America policy. Puerto Rico is an ideal location from which to send emergency and humanitarian assistance to the region and to establish training centers to assist in building judicial and other democratic institutions in Latin America. As important, federal and local cooperation in the national security sphere will improve economic and social conditions on an island fighting crime and chronic underemployment.
Mexico–United States Border Security: From a Bilateral to a Truly Binational Policy Process
Authors: Bronk Christopher , González‐Aréchiga Bernardo
Published: November 2011

This study advocates for a transformative expansion of collaboration between the governments of Mexico and the United States directed at enhancing security in the border region. Protecting security on both sides of the border should be the top priority of all collaboration efforts. With a binational narco‐crisis and the border functioning as a buffer zone, there is a need to bring new ideas forward in ameliorating the externalities produced by the international narcotics and weapons trade. The authors argue that there is no “lesser crime” and that all illegal activity strengthens organized crime in the end. They identify major security problems, prior attempts at remedy, and a roadmap to shared work in formulating and implementing prescriptions. Advocated here is a need for strong border coordinators in each country—based on the border but reaching into the national capitals—that will share staff, resources, planning responsibilities, and intelligence.
Mass Media's Influence on the Transformation of the Mexican Political Regime
Authors: Palavicini Gabriela
Published: November 2011

For many years, mass media has transformed its original role from one of simply informing people to one of shaping societies by making them adopt elements of different cultures. Giving information is only one of its attributes, but in this day and age it is not the main activity. Today, mass media acts more like a group of “feature writers and feature speakers” than of informative channels. Mass media has become an important new player in all states and a decision maker in some spheres. In Mexico, mass media has influenced the adoption of lifestyles and the integration of new traditions and values, but these are not the only aspects in which media intervened. It also has participated in the building of a new political culture that shows people how to become real citizens. This article will study the role of television and the press in the transformation of the Mexican political regime. It will focus on the way that mass media can influence the process of transforming political attitudes by making democratic political values a daily routine.
Transport mechanisms of flavanone aglycones across Caco-2 cell monolayers and artificial PAMPA membranes
Authors: Kobayashi Shoko , Nagai Toshitada , Konishi Yutaka , Tanabe Soichi , Morimoto Kaori , Ogihara Takuo
Published: November 2011

Objectives

We recently reported that flavanone aglycones (hesperetin, naringenin and eriodictyol) are efficiently absorbed via proton-coupled active transport, in addition to transcellular passive diffusion, in Caco-2 cells. Here, we aimed to evaluate in detail the absorption mechanisms of these flavanones, as well as homoeriodictyol and sakuranetin.

Methods

We evaluated the absorption mechanisms of the above compounds by means of in vitro studies in Caco-2 cells in parallel with an artificial membrane permeation assay (PAMPA) under pH-gradient and iso-pH conditions.

Key findings

Comparison of the permeability characteristics of flavanones in Caco-2 cells and in PAMPA under these conditions, as well as a consideration of the physicochemical properties, indicated that hesperetin, naringenin, eriodictyol and homoeriodictyol were efficiently transported by passive diffusion according to the pH-partition hypothesis, except in the case of sakuranetin. However, transport of all flavanones were remarkably temperature-dependent, and was significantly reduced when Caco-2 cells were treated with amino acid-modifying reagents.

Conclusions

Our data confirm that both passive diffusion and an active transport mechanism contribute to flavanone absorption through human intestinal epithelium.
Continuity from an implicit to an explicit understanding of false belief from infancy to preschool age
Authors: Thoermer Claudia , Sodian Beate , Vuori Maria , Perst Hannah , Kristen Susanne
Published: November 2011

An implicit understanding of false belief indicated by anticipatory looking has been shown to be significantly correlated with performance on explicit false‐belief tasks in 3‐ and 4‐year‐old children (Low, 2010). Recent evidence from infant research indicates, however, that implicit false‐belief understanding guides infants’ expectations about goal‐directed actions even in the second year of life. The present study presents data from a sample of N= 70 infants who were tested longitudinally at 15, 18, 30, 36 and 48 months with implicit and explicit Theory of Mind measures, as well as an assessment of verbal IQ. Belief‐based anticipatory looking in the false‐belief task at 18 months significantly predicted verbal false‐belief reasoning at 48 months, after controlling for verbal IQ. These findings indicate developmental continuity and conceptual specificity in belief reasoning from infancy to preschool age. They are discussed with respect to competing accounts of infants’ understanding of the mind.
Deposition of novel nanocomposite films by a newly developed differential pumping co-sputtering system
Authors: Nose Masateru , Kurimoto Takeshi , Saiki Atsushi , Matsuda Kenji , Terayama Kiyoshi
Published: November 2011

A differential pumping co-sputtering system was developed to facilitate a controlled, but flexible fabrication of multifunctional nanocomposite films with compositions not limited by thermodynamic restrictions. This system features a multichamber design with a differential pumping system. Dividing atmospheres with this set up greatly reduced the cross-contamination between chambers, and each material could be co-deposited by rapid rotation of the substrate. The clearance between the substrate holder and the chamber was set at 1–2 mm, and the conductance of the clearance was examined roughly using conductance equations for typical types of orifices. It was found that the potential difference (PD) value of the clearance between the two chambers was less than 0.01; the gas flow between the two chambers through the clearance thus appears to be a practical molecular flow. The PD value, where P is a pressure (Pa) and D is a diameter of an orifice or a pipe (m), is a gas flow indicator or parameter obtained from an equation of Knudsen number. The changes in the oxygen partial pressure and glow discharge plasma in the left chamber were investigated using a process gas monitor (PGM) and optical emission spectroscope (OES) by introducing different gases to each chamber. The PGM results revealed that the cross-contamination of oxygen from the other chamber was suppressed to 10 ± 3% of the original. In addition, the OES measurement for glow discharge plasma did not detect substantial oxygen contamination from the other chamber. Using the newly developed system, an AlN/SiOx nanocomposite film consisting of B4-type AlN and amorphous SiOx was obtained successfully.
Investigation of polarity effects on the degradation of Pd/Ti/Pt ohmic contacts to p-type SiC under current stress
Authors: Downey B. P. , Flemish J. R. , Mohney S. E.
Published: November 2011

Degradation of low resistance Pd/Ti/Pt ohmic contacts to p-SiC under high current density stressing and the effects of polarity are presented. The Pd/Ti/Pt contact is compared to the conventional Ti/Al contact and provides a lower contact resistance, smoother surface morphology, lower required annealing temperature, and better stability under current stressing. A thick Au overlayer is added to both metallizations for continuous direct current (dc) and pulsed dc stressing. A 31% increase in total resistance is measured for the Ti/Al contacts after 20 h of continuous dc stressing at 200 mA for 5 μm radius contacts, compared to an increase of only 2.5% for the Pd/Ti/Pt contacts. Degradation of the entire anode and cathode was observed for the Ti/Al contacts, whereas damage to only the leading edge of the cathode of the Pd/Ti/Pt contacts was found. The degradation behavior of the Pd/Ti/Pt contacts is explained by a polarity effect, where the cathode reached a higher temperature than the anode under continuous dc stressing. When the contacts were instead pulsed with a dc current of 200 mA using 5 μs pulses and a 10% duty cycle, both contact schemes were electrically stable, probably due to the reduced temperature during testing. However, chemical instability of the Ti/Al contacts was still evident, and although the Pd/Ti/Pt ohmic contacts appeared unaltered, voiding between the Au bond pad and the Pd/Ti/Pt metallization occurred.
Companding technique for high dynamic range measurements using Gafchromic films
Authors: Van den Heuvel Frank , Crijns Wouter , Defraene Gilles
Published: November 2011

Purpose:

To introduce a methodology to perform dose measurements using Gafchromic films which can span several decades of dose levels.

Methods:

The technique is based on a rescaling approach using different films irradiated at different dose levels. This is combined with a registration protocol correcting positioning and scaling factors for each film. The methodology is validated using TLD's for out‐of‐field doses. Furthermore, two examples are provided using the technique to characterize small sized radiosurgery cones and compared with measurements made with a pinpoint chamber.

Results:

Excellent agreement with TLD, planning systems and measurement was found. The superior resolution of the film technique was apparent.

Conclusions:

The authors have introduced a new technique allowing users to quantify very low doses in conjunction with commissioning measurements. The use of film also provides 2D information on beam characteristics in high resolution measurements.
Long-Term Antibody and Immune Memory Response Induced by Pulmonary Delivery of the Influenza Iscomatrix Vaccine
Authors: Vujanic Ana , Snibson Kenneth J. , Wee Janet L. K. , Edwards Stirling J. , Pearse Martin J. , Scheerlinck Jean-Pierre Y. , Sutton Philip
Published: November 2011

Pulmonary delivery of an influenza Iscomatrix adjuvant vaccine induces a strong systemic and mucosal antibody response. Since an influenza vaccine needs to induce immunological memory that lasts at least 1 year for utility in humans, we examined the longevity of the immune response induced by such a pulmonary vaccination, with and without antigen challenge. Sheep were vaccinated in the deep lung with an influenza Iscomatrix vaccine, and serum and lung antibody levels were quantified for up to 1 year. The immune memory response to these vaccinations was determined following antigen challenge via lung delivery of influenza antigen at 6 months and 1 year postvaccination. Pulmonary vaccination of sheep with the influenza Iscomatrix vaccine induced antigen-specific antibodies in both sera and lungs that were detectable until 6 months postimmunization. Importantly, a memory recall response following antigenic challenge was detected at 12 months post-lung vaccination, including the induction of functional antibodies with hemagglutination inhibition activity. Pulmonary delivery of an influenza Iscomatrix vaccine induces a long-lived influenza virus-specific antibody and memory response of suitable length for annual vaccination against influenza.
Requirements for Mouse Mammary Tumor Virus Rem Signal Peptide Processing and Function
Authors: Byun Hyewon , Halani Nimita , Gou Yongqiang , Nash Andrea K. , Lozano Mary M. , Dudley Jaquelin P.
Published: November 2011

Mouse mammary tumor virus (MMTV) encodes a Rev-like protein, Rem, which is involved in the nuclear export and expression of viral RNA. Previous data have shown that all Rev-like functions are localized to the 98-amino-acid signal peptide (SP) at the N terminus of MMTV Rem or envelope proteins. MMTV-SP uses endoplasmic reticulum-associated degradation (ERAD) for protein trafficking. Rem cleavage by signal peptidase in the ER is necessary for MMTV-SP function in a reporter assay, but many requirements for trafficking are not known. To allow detection and localization of both MMTV-SP and the C-terminal cleavage product, we prepared plasmids expressing green fluorescent protein (GFP) tags. N-terminal Rem tagging led to protein accumulation relative to untagged Rem and allowed signal peptidase cleavage but reduced its specific activity. C-terminal tagging also led to Rem accumulation yet dramatically reduced cleavage, GFP fluorescence, and activity relative to N-terminally tagged Rem (GFPRem). Substitutions of an invariant leucine at position 71 between the known RNA-binding and nuclear export sequences interfered with GFPRem accumulation and activity but not cleavage. Similarly, deletion of 100 or 150 C-terminal amino acids from GFPRem dramatically reduced both Rem and MMTV-SP levels and function. Removal of the entire C terminus (203 amino acids) restored both protein levels and activity of MMTV-SP. Only C-terminal GFP tagging, and not other modifications, appeared to trap Rem in the ER membrane. Thus, Rem conformation in both the ER lumen and cytoplasm determines cleavage, retrotranslocation, and MMTV-SP function. These mutants further characterize intermediates in Rem trafficking and have implications for all proteins affected by ERAD.
Adenovirus Serotype 5 Neutralizing Antibodies Target both Hexon and Fiber following Vaccination and Natural Infection
Authors: Bradley Ritu R. , Lynch Diana M. , Iampietro Mark J. , Borducchi Erica N. , Barouch Dan H.
Published: November 2011

The immunogenicity of adenovirus serotype 5 (Ad5) vectors has been shown to be suppressed by neutralizing antibodies (NAbs) directed primarily against the hexon hypervariable regions (HVRs). However, the role of NAbs directed against other capsid components, particularly the adenovirus fiber, remains unclear. Here we show that Ad5 NAbs target both hexon and fiber following vaccination and natural infection. Utilizing neutralization assays with capsid chimeric vectors, we observed that NAb responses to hexon appeared dominant and NAb responses against fiber were subdominant in sera from vaccinated mice, vaccinated humans, and naturally exposed humans. A novel chimeric Ad5 vector in which both the hexon HVRs and the fiber knob were exchanged nearly completely evaded Ad5-specific NAbs both
in vitro
and
in vivo
.
HIV Latency in the Humanized BLT Mouse
Authors: Marsden Matthew D. , Kovochich Michael , Suree Nuttee , Shimizu Saki , Mehta Roshni , Cortado Ruth , Bristol Gregory , An Dong Sung , Zack Jerome A.
Published: November 2011

Even after extended treatment with powerful antiretroviral drugs, HIV is not completely eliminated from infected individuals. Latently infected CD4
+
T cells constitute one reservoir of replication-competent HIV that needs to be eliminated to completely purge virus from antiretroviral drug-treated patients. However, a major limitation in the development of therapies to eliminate this latent reservoir is the lack of relevant
in vivo
models that can be used to test purging strategies. Here, we show that the humanized BLT (bone marrow-liver-thymus) mouse can be used as both an abundant source of primary latently infected cells for
ex vivo
latency analysis and also as an
in vivo
system for the study of latency. We demonstrate that over 2% of human cells recovered from the spleens of HIV-infected BLT mice can be latently infected and that this virus is integrated, activation inducible, and replication competent. The non-tumor-inducing phorbol esters prostratin and 12-deoxyphorbol-13-phenylacetate can each induce HIV
ex vivo
from these latently infected cells, indicating that this model can be used as a source of primary cells for testing latency activators. Finally, we show activation-inducible virus is still present following suppression of plasma viral loads to undetectable levels by using the antiretroviral drugs zidovudine, indinavir sulfate, and didanosine, demonstrating that this model can also be used to assess the
in vivo
efficacy of latency-purging strategies. Therefore, the HIV-infected BLT mouse should provide a useful model for assessment of HIV latency activators and approaches to eliminate persistent
in vivo
HIV reservoirs.
Serum angiotensin I-converting enzyme response to exercise; no differential effect of genotype
Authors: Yau A , Moss A D , James L J , Hynes J , Ashworth J J , Evans G H
Published: November 2011

Angiotensin I-converting enzyme (ACE) plays a pivotal role in whole body fluid balance and the degradation of bradykinin. A common allelic variant with a 287 base pair insert has been identified on theACEgene. The homozygous insertion genotype (II) corresponds with lower basal serum ACE concentrations compared to the heterozygous (WI) and homozygous wild type genotypes (WW). Higher circulating levels of ACE may decrease vasodilation; affecting blood flow and sweat loss during exercise. A genotype-independent rise in ACE activity following 20 min of exercise has been reported, but the response to prolonged exercise is unknown. The aim was to examine the influence ofACEgenotype on the serum ACE response to exercise in the heat. Healthy Caucasian males (n=45, 18–45 y) completed 60 min of cycle exercise at (mean ± SD) 62 ± 5% VO2maxin 30.5 ± 0.3°C, with fluidad libitum. Fluid intake and sweat loss were recorded. Venous blood samples were drawn pre, mid, and postexercise for the determination of serum ACE concentration andACEgenotype. Basal serum ACE concentrations were dependent onACEgenotype (WW: 215 ± 57 ng.ml-1;WI: 158 ± 28 ng.ml-1;II: 106 ± 29 ng.ml-1,P<0.001). Serum ACE concentrations increased at 30 min of exercise to 231 ± 55 ng.ml-1, 166 ± 29 ng.ml-1and 115 ± 30 ng.ml-1forWW,WIandII, respectively (P<0.001), and remained elevated post exercise. Serum ACE response was not influenced byACEgenotype (P= 0.321). No differences were found for mean fluid intake (WW: 613 ± 388 ml;WI: 753 ± 385 ml;II: 862 ± 421 ml,P= 0.31), or sweat loss (WW: 1013 ± 257 ml;WI: 1048 ± 254 ml;II: 1257 ± 675 ml,P= 0.28). Serum ACE concentration increased independently ofACEgenotype within 30 min exercise at 30.5°C. Coupled with the lack of genotype effect on sweat loss and fluid intake, these results suggestACEgenotype plays little role in fluid balance during exercise.
The effect of moderate intensity exercise on arterial stiffness in resistance trained athletes, endurance trained athletes and sedentary controls: a cross-sectional observational study
Authors: Hoonjan B , Dulai R , Ahmed M , Lucey A , Morrissey D , Twycross-Lewis R , Greenwald S
Published: November 2011

Increased arterial stiffness is a significant risk factor for cardiovascular mortality. Acute changes to arterial stiffness in athletes following moderate intensity aerobic exercise are unknown. The purpose of this study was to compare central and peripheral arterial stiffness at rest and with moderate intensity exercise in resistance trained (RT) athletes, endurance trained (ET) athletes and sedentary controls. Fifty two participants (18 RT athletes, 19 ET athletes and 15 controls) underwent central (carotid to femoral) and peripheral (femoral to posterior tibial) pulse wave velocity (PWV) measurements before and at intervals 3, 15 and 30 min after half an hour of moderate intensity cycling (65% of maximal heart rate). PWV was measured using Doppler flow velocimeters as pulse detectors and calculated using the ‘foot to foot' velocity method. Groups did not differ in resting central or peripheral PWV. In the endurance and control group, central PWV increased at 3 min postexercise compared with resting values (from 7.7±2.2 to 10.6±4.2 m/s; P = 0.01 and from 7.4±2.2 to 9.1±3.1 m/s; P = 0.02, respectively), followed by a decline to baseline in both groups within 15 min of exercise cessation. The RT group experienced no changes in central PWV, and there were no changes to peripheral PWV postexercise in any group. The study concluded that a 30 min bout of moderate intensity exercise led to a transient increase in central PWV in the endurance and control group, most likely due to mechanisms related to vasoconstriction, but did not reduce arterial stiffness. It is likely that repeated bouts of exercise are needed or a higher intensity of exercise required before reductions in arterial stiffness occur.