bluuebunny/crossref_metadata_2025 huggingface dataset:
Wegener’s granulomatosis: Symptoms, diagnosis, and treatment
Authors: Olivencia‐Simmons Ivelisse
Published: May 2007

Purpose: To provide nurse practitioners with a basic understanding of the clinical presentation, diagnosis, diagnostic testing, pharmacological treatment, and prevalence of Wegener’s granulomatosis (WG).

Data sources: Published research and clinical articles, and a case report.

Conclusions: WG is a systemic disease characterized by vasculitis, necrosis, and granulomas. The diagnosis of WG is difficult, particularly early in the disease process. In order to confirm the diagnosis, the patient should undergo specific tests such as antineutrophil cytoplasm antibodies, erythrocyte sedimentation rate, C‐reactive protein, and biopsy of the tissue involved.

Implications for practice: The diagnosis of WG is often delayed because of the vague symptoms on presentation. Initial symptoms, such as chronic fatigue, upper respiratory infection, sinusitis, and otitis media are common and may not be alarming. Recognizing symptoms, ordering diagnostic tests, and providing appropriate pharmacological therapy is key to diagnosing and treating WG.
Postpartum depression screening by family nurse practitioners
Authors: Goldsmith Marla E.
Published: May 2007

Purpose: The purpose of the study was to identify whether and how nurse practitioners (NPs) screen for postpartum depression, as well as to identify factors affecting such screening.

Data sources: Self‐report data were gathered from 159 questionnaires completed by a convenience sample of family NPs (FNPs) in Illinois and Wisconsin during July 2002.

Conclusions: Despite the fact that 84% of FNP respondents saw at least one postpartum woman yearly, 42% never screened for postpartum depression in any way. The subjects’ confidence in their knowledge of how to use a screening tool was the single best predictor of screening behavior (r= .487). NPs tend to follow clinical practice guidelines, but no guidelines exist to address postpartum depression specifically. Screening for postpartum depression is not universal, making it likely that prevailing estimates of the incidence of this disease are low.

Implications for practice: If the number of NPs who screen for postpartum depression could be increased, many postpartum patients and families could be positively affected. Advanced practice nursing education should adequately prepare graduates to screen at‐risk patients. The development of graduate curricula including thorough units on postpartum depression, as well as formulation of clinical practice guidelines for postpartum depression, could make great strides toward more and better screening, prompt diagnosis, and treatment.
Region specific patellar tendon hypertrophy in humans following resistance training
Authors: Kongsgaard M. , Reitelseder S. , Pedersen T. G. , Holm L. , Aagaard P. , Kjaer M. , Magnusson S. P.
Published: May 2007

Aim: To examine if cross‐sectional area (CSA) differs along the length of the human patellar tendon (PT), and if there is PT hypertrophy in response to resistance training.

Methods: Twelve healthy young men underwent baseline and post‐training assessments. Maximal isometric knee extension strength (MVC) was determined unilaterally in both legs. PT CSA was measured at the proximal‐, mid‐ and distal PT level and quadriceps muscle CSA was measured at mid‐thigh level using magnetic resonance imaging. Mechanical properties of the patellar tendons were determined using ultrasonography. Subsequently, subjects performed 12 weeks of heavy resistance knee extension training with one leg (Heavy‐leg), and light resistance knee extension training with the other leg (Light‐leg).

Results: The MVC increased for heavy‐leg (15 ± 4%,P < 0.05), but not for light‐leg (6 ± 4%). Quadriceps CSA increased in heavy‐legs (6 ± 1%,P < 0.05) while unchanged in light‐legs. Proximal PT CSA (104 ± 4 mm2) was smaller than the mid‐tendon CSA (118 ± 3 mm2), which again was smaller than distal tendon CSA (127 ± 2 mm2,P < 0.05). Light‐leg PT CSA increased by 7 ± 3% (P < 0.05) at the proximal tendon level, but was otherwise unchanged. Heavy‐leg PT CSA increased at the proximal and distal tendon levels by 6 ± 3% and 4 ± 2% respectively (P < 0.05), but was unchanged at the mid tendon level. PT stiffness increased in heavy‐legs (P < 0.05) but was unchanged in light‐legs. Modulus remained unchanged in both legs.

Conclusions: To our knowledge, this study is the first to report tendon hypertrophy following resistance training. Further, the data show that the human PT CSA varies along the length of the tendon.
REPRODUCTIVE PATTERNS OF THE HAWAIIAN MONK SEAL
Authors: Harting Albert L. , Baker Jason D. , Johanos Thea C.
Published: May 2007

Abstract

We evaluated reproductive patterns of the Hawaiian monk seal (Monachus schauinslandi) using a combination of fitted age‐specific reproductive curves and analysis of reproductive patterns of individual females. We review the difficulties inherent in the acquisition and modeling of reproductive data with emphasis on the significance of reproductive senescence to populations with dissimilar age/sex compositions. Validation of the fitted reproductive parameters was accomplished by Monte Carlo sampling of parameter distributions to compare the expected number of pups with the observed production. Although the fitted reproductive functions appear to provide an acceptable fit to the raw reproductive data, we found that the fitted curves did a poor job of predicting the actual pup production in individual years because of high variability among years. To further verify, and elaborate on, the patterns in the pooled (multi‐seal, and multi‐year) rates, we examined attributes of the reproductive performance of individual seals. The attributes included age of primiparity, reproductive rates computed over several age ranges, and the relationship between reproductive performance and seal longevity. Analysis of individual seal patterns reinforced the conclusion that reproductive senescence is operative in monk seal populations.
Zero‐Inflated Discrete Statistical Models for Fecundity Data Analysis in Channel Catfish, Ictalurus punctatus
Authors: Quintero Herbert E. , Abebe Asheber , Davis D. Allen
Published: May 2007

Traditional fecundity analysis, either as number of eggs per body weight of female or number of eggs per gram of egg mass, pay little attention to females that do not spawn. These fecundity variables contain a high proportion of zeroes either because of the absence of eggs or the inability to recover the eggs. Zero‐inflated discrete generalized linear models are an alternative method that can be developed to take into account females that do not spawn. In this case study, we propose discrete generalized linear models that use specially constructed mixture models to handle the excess zeroes such as the zero‐inflated Poisson and zero‐inflated negative binomial models. These models have the advantage of modeling fecundity simultaneously with the probability of spawning. The results show that age was the most significant factor influencing the number of eggs per gram of egg mass, while period of spawning was the most significant factor influencing the number of eggs per female body weight. These were also the most important variables that significantly affected the probability of successful spawning. Model residual diagnostics show that zero‐inflated models exhibit superior performance compared to the traditional models like analysis of covariance, Poisson regression, and negative binomial regression models.
Effects of Dietary Recombinant Bovine Somatotropin Levels on Growth, Plasma Recombinant Bovine Somatotropin Concentrations, and Body Composition of Juvenile Korean Rockfish, Sebastes schlegeli
Authors: Yoo Gwangyeol , Lee Seunghyung , Park Gun Jun , Choi Se‐Min , Eme Okorie Okorie , Kim Young Chul , Kim Kang‐Woong , Kang Yong‐Jin , Bai Sungchul C.
Published: May 2007

This experiment was conducted to study the effects of the graded recombinant bovine somatotropin (rBST) levels on growth, plasma rBST concentrations, and body composition of Korean rockfish, Sebastes schlegeli, and to estimate the optimum oral dosage of rBST. Seven experimental diets were formulated to be isonitrogenous and isocaloric and to contain 49.0% crude protein and 16.7 kJ available energy/g, with 0, 5, 10, 15, 20, 25, or 50 mg rBST/kg body weight (BW)/wk (rBST0, rBST5, rBST10, rBST15, rBST20, rBST25, and rBST50, respectively). After the feeding trial, fish fed all the diets supplemented with rBST showed higher weight gain (WG), feed efficiency (FE), specific growth rate (SGR), and protein efficiency ratio (PER) than those fed the rBST0 diet (P < 0.05). WG of fish fed rBST15, rBST20, rBST25, and rBST50 diets was significantly higher than that of fish fed rBST0 and rBST5 diets (P < 0.05); however, there were no significant differences among fish fed rBST10, rBST15, rBST20, rBST25, and rBST50 diets. FE of fish fed rBST15 and rBST20 diets was significantly higher than that of fish fed rBST0, rBST5, rBST10, and rBST50 diets, and fish fed rBST10, rBST25, and rBST50 diets had significantly higher FE than those fed rBST0 and rBST5 diets (P < 0.05). SGR of fish fed all the diets supplemented with rBST was significantly higher than that of fish fed rBST0 diet (P < 0.05); however, there were no significant differences among fish fed all the diets supplemented with rBST. PER of fish fed rBST15 and rBST20 diets was significantly higher than that of fish fed rBST0, rBST5, and rBST50 diets, and fish fed rBST10, rBST25, and rBST50 diets had significantly higher PER than those fed rBST0 and rBST5 diets (P < 0.05). Whole‐body protein of fish fed rBST15 diet was significantly higher than that of fish fed rBST0, rBST5, and rBST10 diets (P < 0.05); however, there were no significant differences among fish fed rBST15, rBST20, rBST25, and rBST50 diets. Plasma rBST concentrations of fish fed all the diets began to rise at 3 h after oral administration of rBST; the maximum plasma rBST concentration peaked at 12 h and returned to the basal level at 24 h. Broken‐line model analyses of WG and FE were 12.8 and 13.2 mg rBST/kg BW/wk, respectively. These results indicated that the optimum oral dosage could be greater than 12.8 mg rBST/kg BW/wk but less than 13.2 mg rBST/kg BW/wk in juvenile Korean rockfish.
Effects of Dietary Short‐chain Fructooligosaccharides on Intestinal Microflora, Survival, and Growth Performance of Juvenile White Shrimp, Litopenaeus vannamei
Authors: Zhou Zhigang , Ding Zhaokun , Huiyuan L. V.
Published: May 2007

Abstract.— Five groups of juvenile white shrimp, Litopenaeus vannamei, in triplicate were separately fed a compound diet with additional short‐chain fructooligosaccharides (ScFOS, Profeed® 95%) 0, 0.4, 0.8, 1.2, or 1.6 g/kg dried diet for 8 wk to investigate the effects of ScFOS on the intestinal microflora, survival, and growth performance of the shrimp. The juvenile shrimp with around 0.17 g of initial body weight were divided into 30 per tank and reared in a standard water recirculation system at 28 C. The shrimp were fed five times a day. At the end of experiment, the shrimp were weighed and their intestinal samples were analyzed for the amounts of Vibrio parahaemolyticus, Aeromonas hydrophila, Lactobacillus sp., and Streptococcus faecalis using selective agar. The results showed that the shrimps’ weight gain and specific growth rate increased with the increment of dietary ScFOS, while their feed conversion ratio decreased. The result was the best when an additional ScFOS 0.4 g/kg dried diet was used.
Tabloid Imperialism: American Geopolitical Anxieties and the War on Terror
Authors: Debrix François
Published: May 2007

Over the past decade, influential American intellectuals of statecraft have adopted a style of presentation of global political, social, and economic realities that can be described as tabloid geopolitics. Using a discursive style directly borrowed from popular television talk‐shows, news reporting, and punditry, tabloid geopolitics is designed to be highly entertaining, sensational, shocking, and overtly simplistic. Tabloid geopolitics combines commonsensical textual explanations and spectacular maps to produce a sense of fear and inevitable danger that can lead American audiences to accept certain ‘truths’ that geopolitical experts seek to impose. This article traces the path of these discourses of popular geopolitics from ‘tabloid realism’ to ‘tabloid imperialism’. After offering an overview of the tabloid geopolitical genre that takes the reader through the tabloid productions of Robert D. Kaplan, Samuel Huntington, and Thomas Barnett, this essay explores the place of tabloid imperialism today, some 6 years after the 9/11 terrorist attacks. Introducing a recent text by media pundit Tony Blankley, this article shows how previous tabloid realist and tabloid imperialist concerns have given way to a mode of panic tabloid imperialism. Mixing prior tabloid realist and imperialist themes and techniques at a time when uncertainties about the protracted military occupation of Iraq is starting to turn the American public away from the war on terror, Blankley's panic tabloid imperialist text is a somewhat desperate yet, like most tabloid geopolitical discourses, typically hateful, violent and, in the end, self‐defeating attempt at making sense of the place of the West and the United States in the war on terror.
Functional role of A‐type potassium currents in rat presympathetic PVN neurones
Authors: Sonner Patrick M. , Stern Javier E.
Published: May 2007

Despite the fact that paraventricular nucleus (PVN) neurones innervating the rostral ventrolateral medulla (RVLM) play important roles in the control of sympathetic function both in physiological and pathological conditions, the precise mechanisms controlling their activity are still incompletely understood. In the present study, we evaluated whether the transient outward potassium current IA is expressed in PVN‐RVLM neurones, characterized its biophysical and pharmacological properties, and determined its role in shaping action potentials and firing discharge in these neurones. Patch‐clamp recordings obtained from retrogradely labelled, PVN‐RVLM neurones indicate that a 4‐AP sensitive, TEA insensitive current, with biophysical properties consistent with IA, is present in these neurones. Pharmacological blockade of IA depolarized resting Vm and prolonged Na+ action potential duration, by increasing its width and by slowing down its decay time course. Interestingly, blockade of IA either increased or decreased the firing activity of PVN‐RVLM neurones, supporting the presence of subsets of PVN‐RVLM neurones differentially modulated by IA. In all cases, the effects of IA on firing activity were prevented by a broad spectrum Ca2+ channel blocker. Immunohistochemical studies suggest that IA in PVN‐RVLM neurons is mediated by Kv1.4 and/or Kv4.3 channel subunits. Overall, our results demonstrate the presence of IA in PVN‐RVLM neurones, which actively modulates their action potential waveform and firing activity. These studies support IA as an important intrinsic mechanism controlling neuronal excitability in this central presympathetic neuronal population.
Transport Characteristics of Expiratory Droplets and Droplet Nuclei in Indoor Environments With Different Ventilation Airflow Patterns
Authors: Wan M. P. , Chao C. Y. H.
Published: May 2007

Expiratory droplets and droplet nuclei can be pathogen carriers for airborne diseases. Their transport characteristics were studied in detail in two idealized floor-supply-type ventilation flow patterns: Unidirectional–upward and single-side–floor, using a multiphase numerical model. The model was validated by running interferometric Mie imaging experiments using test droplets with nonvolatile content, which formed droplet nuclei, ultimately, in a class-100 clean-room chamber. By comparing the droplet dispersion and removal characteristics with data of two other ceiling-supply ventilation systems collected from a previous work, deviations from the perfectly mixed ventilation condition were found to exist in various cases to different extent. The unidirectional–upward system was found to be more efficient in removing the smallest droplet nuclei (formed from 1.5μm droplets) by air extraction, but it became less effective for larger droplets and droplet nuclei. Instead, the single-side–floor system was shown to be more favorable in removing these large droplets and droplet nuclei. In the single-side–floor system, the lateral overall dispersion coefficients for the small droplets and nuclei (initial size ⩽45μm) were about an order of magnitude higher than those in the unidirectional–upward system. It indicated that bulk lateral airflow transport in the single-side–floor system was much stronger than the lateral dispersion mechanism induced mainly by air turbulence in the unidirectional–upward system. The time required for the droplets and droplet nuclei to be transported to the exhaust vent or deposition surfaces for removal varied with different ventilation flow patterns. Possible underestimation of exposure level existed if the perfectly mixed condition was assumed. For example, the weak lateral dispersion in the unidirectional ventilation systems made expiratory droplets and droplet nuclei stay at close distance to the source leading to highly nonuniform spatial distributions. The distance between the source and susceptible patients became an additional concern in exposure analysis. Relative significance of the air-extraction removal mechanism was studied. This can have impact to the performance evaluation of filtration and disinfection systems installed in the indoor environment. These findings revealed the need for further development in a risk-assessment model incorporating the effect of different ventilation systems on distributing expiratory droplets and droplet nuclei nonuniformly in various indoor spaces, such as buildings, aircraft cabins, trains, etc.
Effect of ACL Deficiency on MCL Strains and Joint Kinematics
Authors: Lujan Trevor J. , Dalton Michelle S. , Thompson Brent M. , Ellis Benjamin J. , Weiss Jeffrey A.
Published: May 2007

The knee joint is partially stabilized by the interaction of multiple ligament structures. This study tested the interdependent functions of the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) by evaluating the effects of ACL deficiency on local MCL strain while simultaneously measuring joint kinematics under specific loading scenarios. A structural testing machine applied anterior translation and valgus rotation (limits 100N and 10Nm, respectively) to the tibia of ten human cadaveric knees with the ACL intact or severed. A three-dimensional motion analysis system measured joint kinematics and MCL tissue strain in 18 regions of the superficial MCL. ACL deficiency significantly increased MCL strains by 1.8% (p<0.05) during anterior translation, bringing ligament fibers to strain levels characteristic of microtrauma. In contrast, ACL transection had no effect on MCL strains during valgus rotation (increase of only 0.1%). Therefore, isolated valgus rotation in the ACL-deficient knee was nondetrimental to the MCL. The ACL was also found to promote internal tibial rotation during anterior translation, which in turn decreased strains near the femoral insertion of the MCL. These data advance the basic structure-function understanding of the MCL, and may benefit the treatment of ACL injuries by improving the knowledge of ACL function and clarifying motions that are potentially harmful to secondary stabilizers.
Extraction of Mechanical Properties of Articular Cartilage From Osmotic Swelling Behavior Monitored Using High Frequency Ultrasound
Authors: Wang Q. , Zheng Y. P. , Niu H. J. , Mak A. F. T.
Published: May 2007

Articular cartilage is a biological weight-bearing tissue covering the bony ends of articulating joints. Negatively charged proteoglycan (PG) in articular cartilage is one of the main factors that govern its compressive mechanical behavior and swelling phenomenon. PG is nonuniformly distributed throughout the depth direction, and its amount or distribution may change in the degenerated articular cartilage such as osteoarthritis. In this paper, we used a 50MHz ultrasound system to study the depth-dependent strain of articular cartilage under the osmotic loading induced by the decrease of the bathing saline concentration. The swelling-induced strains under the osmotic loading were used to determine the layered material properties of articular cartilage based on a triphasic model of the free-swelling. Fourteen cylindrical cartilage-bone samples prepared from fresh normal bovine patellae were tested in situ in this study. A layered triphasic model was proposed to describe the depth distribution of the swelling strain for the cartilage and to determine its aggregate modulus Ha at two different layers, within which Ha was assumed to be linearly dependent on the depth. The results showed that Ha was 3.0±3.2, 7.0±7.4, 24.5±11.1MPa at the cartilage surface, layer interface, and deep region, respectively. They are significantly different (p<0.01). The layer interface located at 70%±20% of the overall thickness from the uncalcified-calcified cartilage interface. Parametric analysis demonstrated that the depth-dependent distribution of the water fraction had a significant effect on the modeling results but not the fixed charge density. This study showed that high-frequency ultrasound measurement together with triphasic modeling is practical for quantifying the layered mechanical properties of articular cartilage nondestructively and has the potential for providing useful information for the detection of the early signs of osteoarthritis.
Robust Strategies for Automated AFM Force Curve Analysis—I. Non-adhesive Indentation of Soft, Inhomogeneous Materials
Authors: Lin David C. , Dimitriadis Emilios K. , Horkay Ferenc
Published: May 2007

The atomic force microscope (AFM) has found wide applicability as a nanoindentation tool to measure local elastic properties of soft materials. An automated approach to the processing of AFM indentation data, namely, the extraction of Young’s modulus, is essential to realizing the high-throughput potential of the instrument as an elasticity probe for typical soft materials that exhibit inhomogeneity at microscopic scales. This paper focuses on Hertzian analysis techniques, which are applicable to linear elastic indentation. We compiled a series of synergistic strategies into an algorithm that overcomes many of the complications that have previously impeded efforts to automate the fitting of contact mechanics models to indentation data. AFM raster data sets containing up to 1024 individual force-displacement curves and macroscopic compression data were obtained from testing polyvinyl alcohol gels of known composition. Local elastic properties of tissue-engineered cartilage were also measured by the AFM. All AFM data sets were processed using customized software based on the algorithm, and the extracted values of Young’s modulus were compared to those obtained by macroscopic testing. Accuracy of the technique was verified by the good agreement between values of Young’s modulus obtained by AFM and by direct compression of the synthetic gels. Validation of robustness was achieved by successfully fitting the vastly different types of force curves generated from the indentation of tissue-engineered cartilage. For AFM indentation data that are amenable to Hertzian analysis, the method presented here minimizes subjectivity in preprocessing and allows for improved consistency and minimized user intervention. Automated, large-scale analysis of indentation data holds tremendous potential in bioengineering applications, such as high-resolution elasticity mapping of natural and artificial tissues.
Lifetime Estimation of Moems Devices
Authors: Bar-Kohany T. , Stern A.
Published: May 2007

Generally, microelectro mechanical systems (MOEMS) devices require encapsulation for protecting their fragile and tiny inner components in a hermetically sealed cavity. Cavity hermeticity can be critical to the device performance and plays a vital role with respect to reliability and long-term drift characteristics of the MOEMS products. The paper presents a theoretical approach for estimation of lifetime of MOEMS devices in terms of cavity’s hermeticity to gases and water. The results are summarized as working maps for MOEMS packaging engineers, in terms of device cavity (internal package volume), equivalent leak rates, and equivalent size of interconnected defects in the bonding zone.
Hardwiring the Brain: Endocannabinoids Shape Neuronal Connectivity
Authors: Berghuis Paul , Rajnicek Ann M. , Morozov Yury M. , Ross Ruth A. , Mulder Jan , Urbán Gabriella M. , Monory Krisztina , Marsicano Giovanni , Matteoli Michela , Canty Alison , Irving Andrew J. , Katona István , Yanagawa Yuchio , Rakic Pasko , Lutz Beat , Mackie Ken , Harkany Tibor
Published: May 2007

The roles of endocannabinoid signaling during central nervous system development are unknown. We report that CB
1
cannabinoid receptors (CB
1
Rs) are enriched in the axonal growth cones of γ-aminobutyric acid–containing (GABAergic) interneurons in the rodent cortex during late gestation. Endocannabinoids trigger CB
1
R internalization and elimination from filopodia and induce chemorepulsion and collapse of axonal growth cones of these GABAergic interneurons by activating RhoA. Similarly, endocannabinoids diminish the galvanotropism of
Xenopus laevis
spinal neurons. These findings, together with the impaired target selection of cortical GABAergic interneurons lacking CB
1
Rs, identify endocannabinoids as axon guidance cues and demonstrate that endocannabinoid signaling regulates synaptogenesis and target selection in vivo.
Single-Molecule Experiments in Vitro and in Silico
Authors: Sotomayor Marcos , Schulten Klaus
Published: May 2007

Single-molecule force experiments in vitro enable the characterization of the mechanical response of biological matter at the nanometer scale. However, they do not reveal the molecular mechanisms underlying mechanical function. These can only be readily studied through molecular dynamics simulations of atomic structural models: “in silico” (by computer analysis) single-molecule experiments. Steered molecular dynamics simulations, in which external forces are used to explore the response and function of macromolecules, have become a powerful tool complementing and guiding in vitro single-molecule experiments. The insights provided by in silico experiments are illustrated here through a review of recent research in three areas of protein mechanics: elasticity of the muscle protein titin and the extracellular matrix protein fibronectin; linker-mediated elasticity of the cytoskeleton protein spectrin; and elasticity of ankyrin repeats, a protein module found ubiquitously in cells but with an as-yet unclear function.
Visual Language Discrimination in Infancy
Authors: Weikum Whitney M. , Vouloumanos Athena , Navarra Jordi , Soto-Faraco Salvador , Sebastián-Gallés Núria , Werker Janet F.
Published: May 2007

This study shows that 4- and 6-month-old infants can discriminate languages (English from French) just from viewing silently presented articulations. By the age of 8 months, only bilingual (French-English) infants succeed at this task. These findings reveal a surprisingly early preparedness for visual language discrimination and highlight infants' selectivity for retaining only necessary perceptual sensitivities.
Ubiquitin-Binding Protein RAP80 Mediates BRCA1-Dependent DNA Damage Response
Authors: Kim Hongtae , Chen Junjie , Yu Xiaochun
Published: May 2007

Mutations in the breast cancer susceptibility gene 1 (
BRCA1
) are associated with an increased risk of breast and ovarian cancers. BRCA1 participates in the cellular DNA damage response. We report the identification of receptor-associated protein 80 (RAP80) as a BRCA1-interacting protein in humans. RAP80 contains a tandem ubiquitin-interacting motif domain, which is required for its binding with ubiquitin in vitro and its damage-induced foci formation in vivo. Moreover, RAP80 specifically recruits BRCA1 to DNA damage sites and functions with BRCA1 in G
2
/M checkpoint control. Together, these results suggest the existence of a ubiquitination-dependent signaling pathway involved in the DNA damage response.
Chondrite Barium, Neodymium, and Samarium Isotopic Heterogeneity and Early Earth Differentiation
Authors: Carlson Richard W. , Boyet Maud , Horan Mary
Published: May 2007

Isotopic variability in barium, neodymium, and samarium in carbonaceous chondrites reflects the distinct stellar nucleosynthetic contributions to the early solar system. We used
148
Nd/
144
Nd to correct for the observed s-process deficiency, which produced a chondrite
146
Sm-
142
Nd isochron consistent with previous estimates of the initial solar system abundance of
146
Sm and a
142
Nd/
144
Nd at average chondrite Sm/Nd ratio that is lower than that measured in terrestrial rocks by 21 ± 3 parts per million. This result strengthens the conclusion that the deficiency in
142
Nd in chondrites relative to terrestrial rocks reflects
146
Sm decayand earlyplanetary differentiation processes.
Genetic Properties Influencing the Evolvability of Gene Expression
Authors: Landry Christian R. , Lemos Bernardo , Rifkin Scott A. , Dickinson W. J. , Hartl Daniel L.
Published: May 2007

Identifying the properties of gene networks that influence their evolution is a fundamental research goal. However, modes of evolution cannot be inferred solely from the distribution of natural variation, because selection interacts with demography and mutation rates to shape polymorphism and divergence. We estimated the effects of naturally occurring mutations on gene expression while minimizing the effect of natural selection. We demonstrate that sensitivity of gene expression to mutations increases with both increasing trans-mutational target size and the presence of a TATA box. Genes with greater sensitivity to mutations are also more sensitive to systematic environmental perturbations and stochastic noise. These results provide a mechanistic basis for gene expression evolvability that can serve as a foundation for realistic models of regulatory evolution.
ATM and ATR Substrate Analysis Reveals Extensive Protein Networks Responsive to DNA Damage
Authors: Matsuoka Shuhei , Ballif Bryan A. , Smogorzewska Agata , McDonald E. Robert , Hurov Kristen E. , Luo Ji , Bakalarski Corey E. , Zhao Zhenming , Solimini Nicole , Lerenthal Yaniv , Shiloh Yosef , Gygi Steven P. , Elledge Stephen J.
Published: May 2007

Cellular responses to DNA damage are mediated by a number of protein kinases, including ATM (ataxia telangiectasia mutated) and ATR (ATM and Rad3-related). The outlines of the signal transduction portion of this pathway are known, but little is known about the physiological scope of the DNA damage response (DDR). We performed a large-scale proteomic analysis of proteins phosphorylated in response to DNA damage on consensus sites recognized by ATM and ATR and identified more than 900 regulated phosphorylation sites encompassing over 700 proteins. Functional analysis of a subset of this data set indicated that this list is highly enriched for proteins involved in the DDR. This set of proteins is highly interconnected, and we identified a large number of protein modules and networks not previously linked to the DDR. This database paints a much broader landscape for the DDR than was previously appreciated and opens new avenues of investigation into the responses to DNA damage in mammals.
Scientific misconduct from the perspective of research coordinators: a national survey: Table 1
Authors: Pryor Erica R , Habermann Barbara , Broome Marion E
Published: May 2007

Objective:To report results from a national survey of coordinators and managers of clinical research studies in the US on their perceptions of and experiences with scientific misconduct.

Methods:Data were collected using the Scientific Misconduct Questionnaire-Revised. Eligible responses were received from 1645 of 5302 (31%) surveys sent to members of the Association of Clinical Research Professionals and to subscribers ofResearch Practitioner, published by the Center for Clinical Research Practice, between February 2004 and January 2005.

Findings:Overall, the perceived frequency of misconduct was low. Differences were noted between workplaces with regard to perceived pressures on investigators and research coordinators, and on the effectiveness of the regulatory environment in reducing misconduct. First-hand experience with an incident of misconduct was reported by 18% of respondents. Those with first-hand knowledge of misconduct were more likely to report working in an academic medical setting, and to report that a typical research coordinator would probably do nothing if aware that a principal investigator or research staff member was involved in an incident of misconduct.

Conclusion:These findings expand the knowledge on scientific misconduct by adding new information from the perspective of research coordinators. The findings provide some data supporting the influence of workplace climate on misconduct and also on the perceived effectiveness of institutional policies to reduce scientific misconduct.
EFFECTS OF COMBINED RADIATIVE AND CONVECTIVE HEAT TRANSFER ON TEMPERATURE BENEATH MODULATED SOURCE
Authors: BOUBAKER KAREM , BOUHAFS M.
Published: May 2007

An analytical solution is presented to the heat equation in the vicinity of a surface fluid, heated by a modulated Gaussian Laser beam and taking into account three heat transfer modes: conduction, radiation and convection. A new calculation method is performed for profiling temperature inside a surface fluid. Comparison with several experimental profiles explains some unexpected temperature profile results as non-Gaussian behaviour.
THE HUBBARD OPERATORS AND THE SLAVE-PARTICLES PATH-INTEGRAL REPRESENTATIONS DESCRIBING THE t-J MODEL
Authors: ZANDRON O. S.
Published: May 2007

In the present work it is shown that the family of first-order Lagrangians for the t-J model and the corresponding correlation generating functional previously found can be exactly mapped into the slave-fermion decoupled representation. Next, by means of the Faddeev-Jackiw symplectic method, a different family of Lagrangians is constructed and it is shown how the corresponding correlation generating functional can be mapped into the slave-boson decoupled representation.
Airway mechanoreceptor deactivation
Authors: Guardiola J. , Proctor M. , Li H. , Punnakkattu R. , Lin S. , Yu J.
Published: May 2007

Airway sensors play an important role in control of breathing. Recently, it was found that pulmonary slowly adapting stretch receptors (SARs) cease after a brief excitation following sodium pump blockade by ouabain. This deactivation can be explained by overexcitation. If this is true, mechanical stimulation of the SARs should also lead to a deactivation. In this study, we recorded unit activity of the SARs in anesthetized, open-chest, and mechanically ventilated rabbits and examined their responses to lung inflation at different constant pressures. Forty-seven of 137 units had a clear deactivation during the lung inflation. The deactivation threshold varied from unit to unit. For a given unit, the higher the inflation pressure, the sooner the deactivation occurs. For example, the SARs deactivated at 3.0 ± 0.3 and 4.8 ± 0.4 s when the lungs were inflated to constant pressures of 30 and 20 cmH2O, respectively ( n = 25, P < 0.0001). The units usually ceased after a brief intense discharge. In some units, their activity shifted to a lower level, indicating a pacemaker switching. Our results support the notion that SARs deactivate due to overexcitation.
Altered respiratory pattern and hypoxic response in transgenic newborn mice lacking the tachykinin-1 gene
Authors: Berner J. , Shvarev Y. , Lagercrantz H. , Bilkei-Gorzo A. , Hökfelt T. , Wickström R.
Published: May 2007

Substance P is known to be involved in respiratory rhythm and central pattern-generating mechanisms, especially during early development. We therefore studied respiratory responses in transgenic newborn mice (Tac1−/−) lacking substance P and neurokinin A (NKA). In vivo, the effects of intermittent isocapnic hypoxia (IH) and hypercapnia were studied using whole body flow plethysmography at P2-3 and P8-10. In vitro, anoxic responses and the effects of hypocapnic and hypercapnic conditions were studied in brain stem-spinal cord preparations (C4 activity) at P2. Hypoxic challenge considerably modified the respiratory activity in transgenic mice displayed in vivo as an attenuated increase in tidal volume during IH. Transgenic mice also showed a more prominent posthypoxic frequency decline in vivo, and posthypoxic neuronal arrests appeared more often in vitro. We recognized two types of sigh activity: with or without a following pause. During IH, the amount of sighs with a pause decreased and those without increased, a redistribution that became stronger with age only in controls. Intermittent anoxia induced long-term facilitation effects in controls, but not in Tac1−/−animals, manifested as an increase in burst frequency in vitro and by an augmentation of ventilation during posthypoxic periods in vivo. Thus our data demonstrate that a functional substance P/NKA system is of great importance for the generation of an adequate respiratory response to hypoxic provocation in newborn mice and during early maturation. It also indicates that substance P (and/or NKA) is involved in the development of the plasticity of the respiratory system.
Dietary Pulverized Konjac Glucomannan Suppresses Scratching Behavior and Skin Inflammatory Immune Responses in NC/Nga Mice
Authors: Onishi Nobukazu , Kawamoto Seiji , Suzuki Hidenori , Santo Hiroyuki , Aki Tsunehiro , Shigeta Seiko , Hashimoto Kunihiko , Hide Michihiro , Ono Kazuhisa
Published: May 2007

Background: Feeding with pulverized konjac glucomannan (PKGM) suppresses the development of eczema and hyper-IgE production in NC/Nga mice, a model of atopic dermatitis. This study aimed to examine the effects of PKGM on scratching behavior and skin inflammatory immune responses in NC/Nga mice. Methods: Four-week-old NC/Nga mice were maintained for 8 or 9 weeks on diet containing PKGM. Scratching behavior and clinical symptoms were evaluated every 2 weeks. Effects of PKGM on cutaneous inflammation were evaluated by histopathological analysis. Local expression levels of substance P and proinflammatory cytokines were measured by ELISA. Results: An increase in scratching behavior was evident from 6 weeks of age in control mice, but this symptom was dose-dependently inhibited in PKGM-fed mice. Continuous PKGM feeding then significantly inhibited eczematous skin lesions including hyperkeratosis, dermal mastocytosis and eosinophilia. Concomitantly, cutaneous overproductions of substance P, IL-10, IL-4, and TNF-α were all suppressed in PKGM-fed mice. Conclusions: PKGM feeding markedly suppressed development of scratching behavior, substance P expression with mastocytosis, and skin inflammatory immune responses in NC/Nga mice.
A NOS1 Gene Polymorphism Associated with Asthma and Specific Immunoglobulin E Response to Mite Allergens in a Colombian Population
Authors: Martínez B. , Barrios K. , Vergara C. , Mercado D. , Jiménez S. , Gusmão L. , Caraballo L.
Published: May 2007

Background: Nitric oxide (NO) is involved in asthma pathogenesis and is synthesized by three isoforms of NO synthase, one of them encoded by NOS1 gene. The CA-repeat and the C5266T SNP in NOS1 exon 29 have been associated with asthma and IgE levels. We thought to test the association of asthma and asthma-related phenotypes with the exon 29 CA-repeat and the C5266T SNP in a Colombian population sample. Methods: The CA-repeat and the C5266T SNP were genotyped in 167 asthmatics and 166 controls using PCR-based fragment length polymorphism and TaqMan assay. We also determined total and mite-specific IgE against Blomia tropicalis and Dermatophagoides pteronyssinus. Results: Three new CA-repeat alleles, 14, 23 and 24 repeats were detected. Allele comprising 16 repeats was associated with asthma (OR: 1.90 (CI 1.22–2.97, pc = 0.028) and low total (pc = 0.02) and specific IgE to B. tropicalis (pc < 0.0001) and D. pteronyssinus (pc < 0.0001). We found no association of the C5266T SNP and asthma or IgE levels. Conclusion:NOS1 exon 29 CA-repeat may be a risk factor for asthma susceptibility and mite specific IgE response in a Colombian population.
Distribution and Expression of RhoA in Rat Retina after Optic Nerve Injury
Authors: Wang Yan-hua , Wang Yi , Wang Dong-wu , Wu Nan , Liu Dong-ning , Yin Zheng-qin
Published: May 2007

Background: RhoA is a small guanosine triphosphatase which participates in signaling pathways of axonal repellents or inhibitors. However, the distribution and expression of RhoA in the rat retina after optic nerve injury has not been elucidated yet. Objectives: To study the distribution and expression of RhoA in the rat retina after optic nerve injury. Methods: Immunohistochemistry was used to determine the distribution of RhoA in rat retina after optic nerve injury. The expression of RhoA was analyzed by Western blot. Results: In normal retina and the retina 1 day after optic nerve injury, RhoA was distributed in the retinal ganglion cell (RGC) layer. Three days after optic nerve injury, it existed in RGCs and the inner plexiform layer. However, 7 days after surgery its immunoreactivity was abundant not only in the RGC and inner plexiform layers but also in the inner nuclear and outer plexiform layers. Western blot analysis showed that the expression of RhoA increased significantly in the retina after optic nerve injury in comparison with normal retina. Conclusion: Theseresults indicate that the distribution and expression of RhoA were extended and enhanced after optic nerve injury, and that RhoA plays an important role in optic nerve regeneration.
Transient Deafness in Young Candidates for Cochlear Implants
Authors: Attias J. , Raveh E.
Published: May 2007

This study describes 5 infants who were diagnosed with auditory neuropathy (AN) associated with severe to profound neural hearing loss shortly after birth. However, on repetition of the tests 7–12 months later, all infants showed full or partial recovery. The follow-up electrophysiological patterns were characterized by the appearance of wave I, followed by wave III and V, reflecting synchronization of auditory pathways and improvement in auditory nerve function. Suspected causative or contributory factors were neonatal hyperbilirubinemia, hypoxia, ischemia, and central nervous system immaturity, alone or in combination. These findings indicate that lack of an auditory brain stem response does not necessarily mean no hearing and that the situation where AN exists can improve. Thus, clinicians should be made aware that although cochlear implants may yield better auditory performance when applied early, they should be considered a therapeutic option only after repeated measures have proved persistent AN, and no child should be considered for an implant until a behavioral measure of hearing has been obtained.
Recipes for Creating Animal Models of Diabetic Cardiovascular Disease
Authors: Hsueh Willa , Abel E. Dale , Breslow Jan L. , Maeda Nobuyo , Davis Richard C. , Fisher Edward A. , Dansky Hayes , McClain Donald A. , McIndoe Richard , Wassef Momtaz K. , Rabadán-Diehl Cristina , Goldberg Ira J.
Published: May 2007

For more than 50 years, investigators have unsuccessfully tried to recreate in experimental animals the cardiovascular complications of diabetes seen in humans. In particular, accelerated atherosclerosis and dilated cardiomyopathy, the major causes of mortality in patients with diabetes, have been conspicuously absent in many mouse models of the disease. Under the auspices of the NIH, the Animal Models of Diabetic Complications Consortium has worked to address this issue. This effort has focused on the development of mouse models because of the high level of genomic information available and the many well-developed genetic manipulations that may be performed in mice. Importantly, the consortium has also worked to standardize many methods to assess metabolic and cardiovascular end points for measurement of the diabetic state and its macrovascular complications. Finally, for maximum benefits from these animal models in the study of atherosclerosis and of other diabetic complications, the consortium has created a system for sharing both the animal models and the accumulated phenotypic data with the greater scientific community.
Calcium Cycling Protein Density and Functional Importance to Automaticity of Isolated Sinoatrial Nodal Cells Are Independent of Cell Size
Authors: Lyashkov Alexey E. , Juhaszova Magdalena , Dobrzynski Halina , Vinogradova Tatiana M. , Maltsev Victor A. , Juhasz Ondrej , Spurgeon Harold A. , Sollott Steven J. , Lakatta Edward G.
Published: May 2007

Spontaneous, localized, rhythmic ryanodine receptor (RyRs) Ca
2+
releases occur beneath the cell membrane during late diastolic depolarization in cardiac sinoatrial nodal cells (SANCs). These activate the Na
+
/Ca
2+
exchanger (NCX1) to generate inward current and membrane excitation that drives normal spontaneous beating. The morphological background for the proposed functional of RyR and NCX crosstalk, however, has not been demonstrated. Here we show that the average isolated SANC whole cell labeling density of RyRs and SERCA2 is similar to atrial and ventricle myocytes, and is similar among SANCs of all sizes. Labeling of NCX1 is also similar among SANCs of all sizes and exceeds that in atrial and ventricle myocytes. Submembrane colocalization of NCX1 and cardiac RyR (cRyR) in all SANCs exceeds that in the other cell types. Further, the Cx43 negative primary pacemaker area of the intact rabbit sinoatrial node (SAN) exhibits robust positive labeling for cRyR, NCX1, and SERCA2. Functional studies in isolated SANCs show that neither the average action potential (AP) characteristics, nor those of intracellular Ca
2+
releases, nor the spontaneous cycle length vary with cell size. Chelation of intracellular [Ca
2+
], or disabling RyRs or NCX1, markedly attenuates or abolishes spontaneous SANC beating in all SANCs. Thus, there is dense labeling of SERCA2, RyRs, and NCX1 in small-sized SANCs, thought to reside within the SAN center, the site of impulse initiation. Because normal automaticity of these cells requires intact Ca
2+
cycling, interactions of SERCA, RyR2 and NCX molecules are implicated in the initiation of the SAN impulse.