bluuebunny/crossref_metadata_2025 huggingface dataset:
Sustained increase of somatosensory cortex excitability by tactile coactivation studied by paired median nerve stimulation in humans correlates with perceptual gain
Authors: Höffken Oliver , Veit Mathias , Knossalla Frauke , Lissek Silke , Bliem Barbara , Ragert Patrick , Dinse Hubert R. , Tegenthoff Martin
Published: August 2007

Cortical excitability can be reliably assessed by means of paired‐pulse stimulation techniques. Recent studies demonstrated particularly for motor and visual cortex that cortical excitability is systematically altered following the induction of learning processes or during the development of pathological symptoms. A recent tactile coactivation protocol developed by Godde and coworkers showed that improvement of tactile performance in humans can be achieved also without training through passive stimulation on a time scale of a few hours. Tactile coactivation evokes plastic changes in somatosensory cortical areas as measured by blood oxygenation level‐dependent (BOLD) activation in fMRI or SEP‐dipole localization, which correlated with the individual gain in performance. To demonstrate changes in excitability of somatosensory cortex after tactile coactivation, we combined assessment of tactile performance with recordings of paired‐pulse SEPs after electrical median nerve stimulation of both the right coactivated and left control hand at ISIs of 30 and 100 ms before, 3 h after and 24 h after tactile coactivation. Amplitudes and latencies of the first and second cortical N20/P25 response components were calculated. For the coactivated hand, we found significantly lowered discrimination thresholds and significantly reduced paired‐pulse ratios (second N20/P25 response/first N20/P25 response) at an ISI of 30 ms after tactile coactivation indicating enhanced cortical excitability. No changes in paired‐pulse behaviour were observed for ISIs of 100 ms. Both psychophysical and cortical effects recovered to baseline 24 h after tactile coactivation. The individual increase of excitability correlated with the individual gain in discrimination performance. For the left control hand we found no effects of tactile coactivation on paired‐pulse behaviour and discrimination threshold. Our results indicate that changes in cortical excitability are modified by tactile coactivation and were scaled with the degree of improvement of the individual perceptual learning. Conceivably, changes of cortical excitability seem to constitute an additional important marker and mechanism underlying plastic reorganization.
Cognitive and emotional information processing: protein synthesis and gene expression
Authors: Sajikumar Sreedharan , Navakkode Sheeja , Korz Volker , Frey Julietta U.
Published: August 2007

Recent findings suggest that functional plasticity phenomena such as long‐term potentiation (LTP) and long‐term depression (LTD) – cellular processes underlying memory – are restricted to functional dendritic compartments. It was also shown, however, that a relatively strong activation of a synaptic input can abolish compartment restrictions. Our data support these findings and we present one cellular pathway responsible for uncompartmentalization of the normally localized plasticity processes by the action of rolipram, an inhibitor of type 4 phosphodiesterases. In contrast with compartment‐restricted information processing, uncompartmentalization requires transcription. In the search for system relevance of compartmentalization versus uncompartmentalization we describe firstly data which show that more cognitive information processing in rats' behaviour may follow rules of compartmentalization, whereas stressful, more life‐threatening, inputs abolish compartment‐restricted information processing involving transcription. Our findings allow us to suggest that consolidation of processes which take place during the cognitive event most probably depend on local protein synthesis, whereas stress immediately induces gene expression in addition, resulting in a compartment‐unspecific up‐regulation of plasticity‐related proteins (PRPs), providing the entire neuron with a higher level of ‘reactiveness’. These data would provide a specific functional cellular mechanism to respond differentially and effectively to behaviourally weighted inputs.
Analytical and Experimental Study of Determining the Optimal Number of Wedge Shape Cutting Teeth in Coring Bits Used in Percussive Drilling
Authors: Liu Yinghui , Mavroidis Constantinos , Bar-Cohen Yoseph , Chang Zensheu
Published: August 2007

In this paper we study the design of the coring bits with wedge-shape cutting teeth of vibratory drills that percussively penetrate into brittle material. The overall coring bit specific energy is analytically derived as a function of the cutting teeth spacing and teeth number. It is found that given the coring bit dimensions and rock material properties, there exist an optimal spacing/depth ratio and an optimal tooth number that minimize the coring bit specific energy and hence maximize the coring bit’s drilling rate. Experimental drilling tests were performed to corroborate the analytical results. It was shown that the laboratory drilling tests follow the trend predicted by the theoretical analysis.
Process-Driven Input Profiling for Plastics Processing
Authors: Dong Shaoqiang , E Chunsheng , Fan Bingfeng , Danai Kourosh , Kazmer David O.
Published: August 2007

Most plastic processing set points are variables that need to be defined for each sample point of the cycle. However, in the absence of on-line measures of part quality, the set points cannot be defined by feedback and need to be prescribed a priori for the entire cycle. In conventional practice, the shape of each set-point profile is defined either heuristically, according to qualitative experience, or mechanistically, to enforce a predefined trajectory for a simulated internal process state that is used as a surrogate measure of part quality (e.g., the velocity profile defined to dictate a constant melt front velocity). The purpose of this study is twofold: (i) to evaluate the efficacy of using a single internal state as the surrogate of part quality, and (ii) to explore the feasibility of devising a multivariate profiling approach, where indices of multiple process states act as surrogates of part quality. For this study, an injection-compression molding process used for production of digital video disks was considered as the development domain, and a pseudo-optimal cycle of the process was found by reinforcement learning to provide a basis for evaluating the ideal behavior of the process states. Compared to conventional molding, the results indicate that the asymmetric process capability index, CPK, was increased by ∼50% with velocity profile optimization and to 120% with both velocity profile and pressure profile optimization. Two general conclusions result. First, velocity and pressure profiling provide important degrees of freedom for optimizing process control and maximizing part quality. Second, estimators for unobservable process states, in this case birefringence and warpage, can be used to develop different machine profiles to selectively trade off multiple quality attributes according to user preferences.
Investigation of the Tooth Geometry of a Hob for Machining of Involute Gears (in the Tool-in-Use Reference System)
Authors: Radzevich Stephen P.
Published: August 2007

This paper is aiming at development of an analytical approach for computation of the geometrical parameters of cutting edges of an involute hob. It is well recognized that the involute hob geometry strongly affects the cutting tool performance, as well as the efficiency of gear hobbing operation. It is proven experimentally and by industrial practice that the optimal value of every geometrical parameter of the tool cutting edge exists and, thus, it can be found out. A method for computation of the cutting edge geometry is necessary for optimization of parameters of a gear hobbing operation. In this paper, an analytical method for the computation of the cutting edge geometry of a gear hob is reported. The method is based on wide application of elements of vector calculus and matrices. The analysis is performed in the tool-in-use reference system. An equation of the penetration curve is derived. The machining zone is partitioned onto several different sectors. The roughing sector and the generating sector are distinguished. Generating of the work-gear tooth profile occurs within the generating sector that is bounded by the penetration curve. The derived equations, as well as the worked-out computer codes are applicable for computation of the cutting edge geometry at any point of the cutting edge of the hob, and at a any instant of time. The equations and the computer codes enable one estimating the impact of (a) the hob diameter, (b) the hob number of starts, (c) the work-gear number of teeth, (d) the hob feed rate, and (e) the hob rotation onto the actual values of the geometrical parameters of the hob cutting edges. Numerical results of the investigation are computed using commercial software MATHCAD-SCIENTIFIC. The results of the computation of the cutting edge geometry of the involute hob enable the user (a) to avoid not-feasible values of any and all geometrical parameters of the cutting edge of the hob teeth, (b) to develop parameters of the hob grinding and reliving operations, which guaranteed the optimal values of any and all geometrical parameters of the hob cutting edges. Ultimately, the application of the hobs with optimal geometry of the cutting edges will result in an increase in the cutting tool performance and in the efficiency of the gear hobbing operation. The latter is of critical importance for high volute production of involute gears for the needs of the automotive industry. The reported research results are ready to be put into practice.
Analytical Modeling of Chatter Stability in Turning and Boring Operations—Part I: Model Development
Authors: Ozlu Emre , Budak Erhan
Published: August 2007

In this paper an analytical model for stability limit predictions in turning and boring operations is proposed. The multidimensional model includes the three-dimensional geometry of the processes resulting in an eigenvalue problem. In addition, a model for the chip thickness at the insert nose is proposed to observe the effect of the insert nose radius on the chatter stability limit. The model represents a development over existing ones due to accurate treatment of the multidimensional process dynamics and geometry, and resulting practical formulas for stability limit predictions. Chatter experiments are conducted for both turning and boring in order to verify the model predictions, and overall, an acceptable agreement is observed.
Analytical Modeling of Chatter Stability in Turning and Boring Operations—Part II: Experimental Verification
Authors: Ozlu Emre , Budak Erhan
Published: August 2007

In this part of the paper series, chatter experiments are conducted in order to verify the proposed stability models presented in the first part (Ozlu, E., and Budak, E., 2007, ASME J. Manuf. Sci. Eng., 129(4), pp. 726–732). Turning and boring chatter experiments are conducted for the cases where the tool or the workpiece is the most flexible component of the cutting system. In addition, chatter experiments demonstrating the effect of the insert nose radius on the stability limit are presented. Satisfactory agreement is observed between the analytical predictions and the experimental results.
Signatures of Electron Fractionalization in Ultraquantum Bismuth
Authors: Behnia Kamran , Balicas Luis , Kopelevich Yakov
Published: August 2007

Because of the long Fermi wavelength of itinerant electrons, the quantum limit of elemental bismuth (unlike most metals) can be attained with a moderate magnetic field. The quantized orbits of electrons shrink with increasing magnetic field. Beyond the quantum limit, the circumference of these orbits becomes shorter than the Fermi wavelength. We studied transport coefficients of a single crystal of bismuth up to 33 tesla, which is deep in this ultraquantum limit. The Nernst coefficient presents three unexpected maxima that are concomitant with quasi-plateaus in the Hall coefficient. The results suggest that this bulk element may host an exotic quantum fluid reminiscent of the one associated with the fractional quantum Hall effect and raise the issue of electron fractionalization in a three-dimensional metal.
Selecting appropriate study designs to address specific research questions in occupational epidemiology
Authors: Checkoway Harvey , Pearce Neil , Kriebel David
Published: August 2007

Various epidemiological study designs are available to investigate illness and injury risks related to workplace exposures. The choice of study design to address a particular research question will be guided by the nature of the health outcome under study, its presumed relation to workplace exposures, and feasibility constraints. This review summarises the relative advantages and limitations of conventional study designs including cohort studies, cross-sectional studies, repeated measures studies, case-control (industry- and community-based) studies, and more recently developed variants of the nested case-control design: case-cohort and case-crossover studies.
Treatment with Rhubarb Improves Brachial Artery Endothelial Function in Patients with Atherosclerosis: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
Authors: Liu Yun-Fang , Yu Hui-Ming , Zhang Cheng , Yan Fang-Fang , Liu Yan , Zhang Yun , Zhang Mei , Zhao Yu-Xia
Published: August 2007

Rhubarb has been used to decrease plasma cholesterol levels and reduce vascular endothelial cellular damage in recent years. However, it is not known whether reported lipid-lowering effects are associated with the improvement of endothelial function. This work aimed to elucidate the therapeutic effects of rhubarb on serum lipids and brachial artery endothelial function, as well as to investigate the relationship between them. One hundred and three patients with atherosclerosis were randomly divided into two groups: patients in the control and the trial group received a placebo and rhubarb, respectively, in addition to the 6 month baseline therapy. Serum lipids and brachial artery endothelial functions were measured in all patients before and after treatment. A total of 83 patients completed the 6-month follow-up protocol. Serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in the trial group decreased significantly and LDL-C was significantly lower than that in the control group. Flow-mediated dilation (FMD) in the trial group was significantly higher after treatment in comparison to the baseline and to the control group. Improvement in FMD correlated with the decreased magnitude of TC and LDL-C levels. The results obtained appeared to confirm that rhubarb significantly improves endothelial function mainly due to lipid-lowering effects in patients with atherosclerosis.
Effects of a Taiji and Qigong Intervention on the Antibody Response to Influenza Vaccine in Older Adults
Authors: Yang Yang , Verkuilen Jay , Rosengren Karl S. , Mariani Rachel A. , Reed Michael , Grubisich Scott A. , Woods Jeffrey A.
Published: August 2007

Previous studies have suggested that Taiji practice may improve immune function. This study was intended to examine whether 5 months of moderate Taiji and Qigong (TQ) practice could improve the immune response to influenza vaccine in older adults. Fifty older adults (mean age 77.2 ± 1.3 years) participated in this study (TQ N = 27; wait-list control [CON] N = 23). Baseline pre-vaccine blood samples were collected. All subjects then received the 2003–2004 influenza vaccine during the first week of the intervention. Post-vaccine blood samples were collected 3, 6 and 20 weeks post-intervention for analysis of anti-influenza hemagglutination inhibition (HI) titers. We found a significant ( p < 0.05) increase in the magnitude and duration of the antibody response to influenza vaccine in TQ participants when compared to CON. The vaccination resulted in a 173, 130, and 109% increase in HI titer at 3, 6, and 20 weeks post-vaccine, respectively, in the TQ group compared to 58, 54, and 10% in CON. There was a significant between group difference at 3 and 20 weeks post-vaccine and at 20 weeks the TQ group had significantly higher titers compared to the pre-vaccine time point, whereas the CON group did not. A higher percentage of TQ subjects also responded to the influenza A strains with a protective (> 40HI) antibody response (37% TQ vs. 20% CON for the H1N1 strain and 56% TQ vs. 45% CON for the H3N2 strain), but the differences between groups were not statistically significant. Traditional TQ practice improves the antibody response to influenza vaccine in older adults, but further study is needed to determine whether the enhanced response is sufficient to provide definitive protection from influenza infection.
Transcriptome Analysis of Cold Syndrome Using Microarray
Authors: Yang Liping , Wang Miqu , Wu Wei , Zhang Louxin
Published: August 2007

Microarrays are widely used to study changes in gene expression in diseases. In this paper, we use this technology to discover gene expression patterns in the cold syndrome in Chinese medicine. We identify differentially expressed genes and extracted gene modules that are enriched with differentially expressed genes in the cold syndrome by analyzing cDNA samples, which are purified from blood taken from a pedigree. Our results suggest that the cold syndrome might be caused by the physiological imbalance and/or the disorder of metabolite processes. The study confirms the hypotheses about molecular pathways responsible to human metabolic-related diseases.
Treatment of Chronic Liver Injuries in Mice by Oral Administration of Ethanolic Extract of the Fruit ofHovenia dulcis
Authors: Fang Hsun-Lang , Lin Hui-Yi , Chan Ming-Che , Lin Wei-Lii , Lin Wen-Chuan
Published: August 2007

The present study examined the effects of an ethanolic extract of the fruit of Hovenia dulcis (EHD) on chronic hepatitis induced by carbon tetrachloride ( CCl4) in mice. CCl4(5%; 0.1 ml/10 g body weight) was given twice a week for 9 weeks, and mice received EHD throughout the entire experimental period. Plasma activities of GPT and GOT, and hepatic levels of malondialdehyde were significantly lowered in mice treated with EHD as compared to mice treated with CCl4only. Histological evaluation showed that EHD could attenuate the liver fibrosis and necrosis caused by CCl4. RT-qPCR analysis also showed that EHD treatment decreased hepatic collagen (α1)(I) and collagen (α1)(III) mRNA expressions. Chronic CCl4treatment caused liver injuries in mice, characterized by an increase in hepatic methionine adenosyltransferase (MAT) 2A gene expression, and decreased MAT1A gene expression. EHD significantly reduced the changes in MAT gene expression due to the chronic CCl4treatment. These results clearly demonstrate that the EHD can reduce hepatic injuries in mice induced by CCl4.
MAGNETISM AT THE NANOSCALE: THE CASE OF FePt
Authors: ANTONIAK C. , FARLE M.
Published: August 2007

Fe x Pt 1-x nanoparticles prepared by organometallic synthesis and gas-phase condensation were structurally and magnetically characterised. The effective spin magnetic moments at both the Fe and Pt sites are reduced with respect to the moments in the corresponding bulk material by up to 20% and further decrease with decreasing particle size at the Fe sites. The ratio of orbital-to-effective-spin magnetic moment [Formula: see text] at the Fe sites increases from 2.1% for 6 nm particles to 3.4% for 3.4 nm particles due to the break of symmetry at the surface. A lowering of the crystal symmetry after the transformation to the chemically ordered L1 0 state yields a [Formula: see text] ≈ 9% and is accompanied by an enhancement of the coercive field at 15 K from (36±5) mT to (292±8) mT indicating an increase of the anisotropy.
Developmental Genetics of Adaptation in Fishes: The Case for Novelty
Authors: Streelman J.T. , Peichel C.L. , Parichy D.M.
Published: August 2007

During the past decade of study in evolutionary developmental biology, we have seen the focus shift away from the stunning conservation of form and function between distantly related taxa toward the causal explanation of differences between closely related species. A number of fish models have emerged at the forefront of this effort to dissect the developmental genetic and molecular basis of evolutionary novelty and adaptation. We review the highlights of this research, concentrating our attention on skeletal morphology (cranial and postcranial), pigmentation patterning, and sex determination. Thus far, the genes involved in adaptation among fishes belong to well-characterized molecular pathways. We synthesize the current state of knowledge to evaluate theories about the interplay between development and evolution. General rules of evolutionary change have not materialized; however, the field is wide open, and fishes will likely continue to contribute insights to this central biological question.
Terrestrial Carbon–Cycle Feedback to Climate Warming
Authors: Luo Yiqi
Published: August 2007

The coupled carbon-climate models reported in the literature all demonstrate a positive feedback between terrestrial carbon cycles and climate warming. A primary mechanism underlying the modeled positive feedback is the kinetic sensitivity of photosynthesis and respiration to temperature. Field experiments, however, suggest much richer mechanisms driving ecosystem responses to climate warming, including extended growing seasons, enhanced nutrient availability, shifted species composition, and altered ecosystem-water dynamics. The diverse mechanisms likely define more possibilities of carbon-climate feedbacks than projected by the kinetics-based models. Nonetheless, experimental results are so variable that we have not generated the necessary insights on ecosystem responses to effectively improve global models. To constrain model projections of carbon-climate feedbacks, we need more empirical data from whole-ecosystem warming experiments across a wide range of biomes, particularly in tropic regions, and closer interactions between models and experiments.
Nicotinic Acid: Pharmacological Effects and Mechanisms of Action
Authors: Gille Andreas , Bodor Erik T. , Ahmed Kashan , Offermanns Stefan
Published: August 2007

Pharmacological doses of nicotinic acid induce a profound change in the plasma levels of various lipids and lipoproteins. The ability of nicotinic acid to strongly increase the plasma concentration of high-density lipoprotein (HDL) cholesterol has in recent years led to an increased interest in the pharmacological potential of nicotinic acid. There is increasing evidence that nicotinic acid alone or in addition to LDL cholesterol–lowering drugs can reduce the progression of atherosclerosis and reduce the risk of cardiovascular events. The clinical use of nicotinic acid is, however, hindered by harmless but unpleasant side effects, especially by a strong cutaneous vasodilation called flushing. The recent discovery of the G protein–coupled receptor GPR109A (HM74A or PUMA-G) as a receptor for nicotinic acid has allowed for better understanding of the mechanisms underlying the metabolic and vascular effects of nicotinic acid. On the basis of recent progress in understanding the pharmacological effects of nicotinic acid, new strategies are in development to better exploit the pharmacological potential of nicotinic acid. New drugs acting via the nicotinic acid receptor or related receptors, as well as new co-medications that suppress unwanted effects of nicotinic acid, will most likely be introduced as new therapeutic options in the treatment of dyslipidemia and the prevention of cardiovascular diseases.
Stimulation of voltage-dependent Ca2+channels by NO at rat myenteric neurons
Authors: Sitmo Mabruka , Rehn Matthias , Diener Martin
Published: August 2007

The aim of the present study was to characterize the action of the neurotransmitter NO on rat myenteric neurons. A NO donor such as GEA 3162 (10−4mol/l) induced an increase in the intracellular Ca2+concentration as indicated by an increase in the fura 2 ratio in ganglia loaded with this Ca2+-sensitive fluorescent dye. The effect of GEA 3162 was strongly reduced in the absence of extracellular Ca2+, suggesting an influx of Ca2+from the extracellular space evoked by NO. A similar nearly complete inhibition was observed in the presence of Ca2+channel blockers such as Ni2+(5 × 10−4mol/l) or nifedipine (10−6mol/l). Whole cell patch-clamp recordings confirmed the activation of voltage-dependent Ca2+channels, measured as inward current carried by Ba2+, by the NO donor. The peak Ba2+-carried inward current increased from −100 ± 19 to −185 ± 34 pA in the presence of sodium nitroprusside (10−4mol/l). The consequence was a hyperpolarization of the membrane, which was blocked by intracellular Cs+and thus most probably reflects the activation of Ca2+-dependent K+channels. Furthermore, at least two subtypes of NO synthases, NOS-1 (neuronal form) and NOS-3 (endothelial form), were found as transcripts in mRNA isolated from the rat myenteric ganglia. The expression of these NO synthases was confirmed immunohistochemically. These observations suggest that NO, released from nitrergic neurons within the enteric nervous system, not only affects target organs such as smooth muscle cells in the gut but has in addition profound effects on the enteric neurons themselves, the key players in the regulation of many gastrointestinal functions.
C-type natriuretic peptide enhances amylase release through NPR-C receptors in the exocrine pancreas
Authors: Sabbatini María E. , Rodríguez Myrian , di Carlo María B. , Davio Carlos A. , Vatta Marcelo S. , Bianciotti Liliana G.
Published: August 2007

Several studies show that C-type natriuretic peptide (CNP) has a modulatory role in the digestive system. CNP administration reduces both jejunal fluid and bile secretion in the rat. In the present study we evaluated the effect of CNP on amylase release in isolated pancreatic acini as well as the receptors and intracellular pathways involved. Results showed that all natriuretic peptide receptors were expressed not only in the whole pancreas but also in isolated pancreatic acini. CNP stimulated amylase secretion with a concentration-dependent biphasic response; maximum release was observed at 1 pM CNP, whereas higher concentrations gradually attenuated it. The response was mimicked by a selective natriuretic peptide receptor (NPR-C) agonist and inhibited by pertussis toxin, strongly supporting NPR-C receptor activation. CNP-evoked amylase release was abolished by U-73122 (PLC inhibitor) and 2-aminoethoxydiphenyl borate (2-APB) [an inositol 1,4,5-triphosphate (IP3) receptor antagonist], partially inhibited by GF-109203X (PKC inhibitor), and unaltered by ryanodine or protein kinase A (PKA) and protein kinase G (PKG) inhibitors. Phosphoinositide hydrolysis was enhanced by CNP at all concentrations and abolished by U-73122. At 1 and 10 pM, CNP did not affect cAMP or guanosine 3′,5′-cyclic monophosphate (cGMP) levels, but at higher concentrations it increased cGMP and diminished cAMP content. Present findings show that CNP stimulated amylase release through the activation of NPR-C receptors coupled to the PLC pathway and downstream effectors involved in exocytosis. The attenuation of amylase release was likely related to cAMP reduction. The augmentation in cGMP supports activation of NPR-A/NPR-B receptors probably involved in calcium influx. Present findings give evidence that CNP is a potential direct regulator of pancreatic function.
Prediction of atherosclerotic plaque ruptures with high-frequency ultrasound imaging and serum inflammatory markers
Authors: Chen Wen Qiang , Zhang Lei , Liu Yun Fang , Chen Liang , Ji Xiao Ping , Zhang Mei , Zhao Yu Xia , Yao Gui Hua , Zhang Cheng , Wang Xing Li , Zhang Yun
Published: August 2007

Atherosclerotic plaque rupture and thrombosis are the main causes of acute coronary syndrome. In the present study, we investigated whether ultrasound imaging and inflammatory parameters are predictive of plaque rupture in a newly established animal model. We developed a rabbit model for plaque rupture by locally delivering recombinant p53 adenovirus to plaques in rabbits fed a high-cholesterol diet for 10 wk, and plaque rupture was triggered using Chinese Russell's viper venom and histamine. We found that 81.1% of rabbits transfected with p53 ( n = 37) had the ruptured plaques, which was significantly higher than results in rabbits transfected with the control vector (26.3%, n = 38; P < 0.001). Among measured biomarkers, high-sensitive C-reactive protein, soluble intercellular adhesion molecule-1, and soluble vascular cell adhesion molecule-1 were significantly different between rabbits with and without ruptured plaques. Using high-frequency duplex and intravascular ultrasound imaging techniques, we obtained a list of parameters. With the multivariate logistic regression model, we identified that plaque eccentric index, plaque area, high-sensitive C-reactive protein, and corrected integrated backscatter intensity were significant predictors of plaque rupture, with odds ratios of 7.056 [95% confidence interval (CI): 1.958, ∼25.430], 1.942 (95% CI: 1.058, ∼3.564), 1.025 (95% CI: 1.007, ∼1.043), and 0.856 (95% CI: 0.775, ∼0.946), respectively. Localized p53 overexpression technique induces plaque rupture, and the combined measurement of ultrasound and biochemical markers is a valuable tool in predicting plaque rupture.
Mismatch between uniform increase in cardiac glucose uptake and regional contractile dysfunction in pacing-induced heart failure
Authors: Lionetti Vincenzo , Guiducci Letizia , Simioniuc Anca , Aquaro Giovanni D. , Simi Claudia , De Marchi Daniele , Burchielli Silvia , Pratali Lorenza , Piacenti Marcello , Lombardi Massimo , Salvadori Piero , Pingitore Alessandro , Neglia Danilo , Recchia Fabio A.
Published: August 2007

Increased glucose utilization and regional differences in contractile function are well-known alterations of the failing heart and play an important pathophysiological role. We tested whether, similar to functional derangement, changes in glucose uptake develop following a regional pattern. Heart failure was induced in 13 chronically instrumented minipigs by pacing the left ventricular (LV) free wall at 180 beats/min for 3 wk. Regional changes in contractile function and stress were assessed by magnetic resonance imaging, whereas regional flow and glucose uptake were measured by positron emission tomography utilizing, respectively, the radiotracers [13N]ammonia and 18F-deoxyglucose. In heart failure, LV end-diastolic pressure was 20 ± 4 mmHg, and ejection fraction was 35 ± 4% (all P < 0.05 vs. control). Sustained pacing-induced dyssynchronous LV activation caused a more pronounced decrease in LV systolic thickening (7.45 ± 3.42 vs. 30.62 ± 8.73%, P < 0.05) and circumferential shortening (−4.62 ± 1.0 vs. −7.33 ± 1.2%, P < 0.05) in the anterior/anterior-lateral region (pacing site) compared with the inferoseptal region (opposite site). Conversely, flow was reduced significantly by ∼32% compared with control and was lower in the opposite site region. Despite these nonhomogeneous alterations, regional end-systolic wall stress was uniformly increased by 60% in the failing LV. Similar to wall stress, glucose uptake markedly increased vs. control (0.24 ± 0.004 vs. 0.07 ± 0.01 μmol·min−1·g−1, P < 0.05), with no significant regional differences. In conclusion, high-frequency pacing of the LV free wall causes a dyssynchronous pattern of contraction that leads to progressive cardiac failure with a marked mismatch between increased glucose uptake and regional contractile dysfunction.
Intravascular pressure and diameter profile of the utero-ovarian resistance artery network: estrous cycle-dependent modulation of resistance artery tone
Authors: Sweeney Terrence E. , Bagher Pooneh , Bailey Jocelyn , Cherra Salvatore J. , Grisafi Frank N. , Pauli Eric M. , Riley Kristin , Soares Sarita
Published: August 2007

Blood flow to the ovary varies dramatically in both magnitude and distribution throughout the estrous cycle to meet the hormonal and metabolic demands of the ovarian parenchyma as it cyclically develops and regresses. Several vascular components appear to be critical to vascular regulation of the ovary. As a first step in resolving the role of the resistance arteries and their paired veins in regulating ovarian blood flow and transvascular exchange, we characterized the architecture and intravascular pressure profile of the utero-ovarian resistance artery network in an in vivo preparation of the ovary of the anesthetized Golden hamster. We also investigated estrous cycle-dependent changes in resistance artery tone. The right ovary and the cranial aspect of the uterus in 26 female hamsters were exposed for microcirculatory observations. Estrous-cycle phase was determined in each animal before experimentation. The utero-ovarian vascular architecture was determined and resistance artery diameters were measured in each animal by video microscopy. Servo-null intravascular pressure measurements were made throughout the uteroovarian arterial network in 11 of the animals. Architectural data showed a complex anastomotic network jointly supplying the uterus and ovary. Resistance arteries showed a high degree of coiling and close apposition to veins, maximizing countercurrent-exchange capabilities. Arterial pressure dropped below 60% of systemic arterial pressure before the arteries entered the ovary. Both the ovarian artery and the uterine artery, which jointly feed the ovary, showed cycle day-dependent changes in diameter. Arterial diameters were smallest on the day following ovulation, during the brief luteal phase of the hamster. The data show that resistance arteries comprise a critical part of a complex network designed for intimate local communication and control and suggest that these arteries may play an important role in regulating ovarian blood flow in an estrous cycle-specific manner.
Effect of PEEP on induced constriction is enhanced in decorin-deficient mice
Authors: Salerno Francesco G. , Pinelli Valentina , Pini Laura , Tuma Bodil , Iozzo Renato V. , Ludwig Mara S.
Published: August 2007

Decorin ( Dcn), a small leucine-rich proteoglycan, is present in the extracellular matrix of the airways and lung tissues, contributes to lung mechanical properties, and its deposition is altered in asthma. The effect of Dcn deficiency on airway parenchymal interdependence was examined during induced bronchoconstriction. Studies were performed in C57Bl/6 mice in which the Dcn gene was disrupted by targeted deletion ( Dcn−/−) and in wild-type controls ( Dcn+/+). Mice were mechanically ventilated, and respiratory system impedance was measured during in vivo ventilation at positive end-expiratory pressure (PEEP) = 2 and 10 cmH20, before and after aerosol delivery of methacholine (MCh). Length vs. tension curves in isolated tracheal rings were measured in vitro. Dcn distribution in +/+ mice airways was characterized by immunofluorescence; differences in collagen structure in Dcn+/+ and Dcn−/− mouse lungs was examined by electron microscopy. MCh caused similar increases in airway resistance (Raw) and tissue elastance (H) in Dcn+/+ and Dcn−/− mice. During MCh-induced constriction, increasing PEEP caused a decrease in Raw that was greater in Dcn−/− mice and a decrease in H in Dcn−/− mice only. Tracheal ring compliance was greater in Dcn −/− mice. Imaging studies showed that Dcn was deposited primarily in the airway adventitial layer in Dcn+/+ mice; in Dcn−/− mice, collagen had an irregular appearance, especially in the lung periphery. These results show that lack of Dcn alters the normal interaction between airways and lung parenchyma; in asthma, changes in Dcn could potentially contribute to abnormal airway physiology.
Biobank Governance: Trends and Perspectives
Authors: Gottweis H. , Zatloukal K.
Published: August 2007

Biobanks are a challenge and topic for governance. Today, biobanks are identified as a biomedical scientific/infrastructural development that warrants a political/legal/ethical reaction with the goal to integrate biobanks into the preexisting fabric of regulation, medicine, law and society. Biobank governance is always a response to sociocultural challenges and requires the building of trust, acceptance, and careful political negotiation. Biobanks are regulated in networks of governance in which the state is one actor next to others, and the ordering and structuring of the interaction between biobanks, society, and politics operates through a variety of actors, on different levels and along particular rationalities. Such networks of governance reflect, to some extent, a postregulatory state in which governance has become a complicated architecture and field of action involving a multitude of forces and rationalities. Biobank governance is still a relatively new field of political-legal intervention and it will be crucial for the future of biobanks to establish governance regimes that appropriately link research with society and politics.
Tissue Banking in a Regulated Environment – Does This Help the Patient?
Authors: Borisch Bettina
Published: August 2007

Several scandals related to tissue collection have questioned the position of patients regarding tissue banking. The Human Tissue Act in the UK is a legal framework for tissue banking that has been evaluated by the Europa Donna Forum UK, an advocacy organisation for breast cancer. Patients are well aware of the importance of clinical research and want to see it strengthened. They envisage several modalities for tissue banking. One modality is the ‘patient-driven’ bank where some of the individual rights are transferred to the community, research done with the tissues is partly controlled by the patients, and information regarding the results is obtained back. However, for all models proposed, the point of prime importance for patients is the issue of consent.
Biobanking for Epidemiological Research and Public Health
Authors: Brand Angela M. , Probst-Hensch Nicole M.
Published: August 2007

Almost all healthcare systems are currently facing fundamental challenges. New ways of organizing these systems based on novel knowledge and stakeholders’ different needs are required to meet these challenges at the appropriate time. In this context, the issue of biobanking has become a specific challenge having major implications for future research and policy strategies as well as for the healthcare systems in general. Medicine is currently undergoing remarkable developments from its morphological and phenotype orientation to a molecular and genotype orientation, promoting the importance of prognosis and prediction. Yet, the discussion about the relevance of integrating genome-based information into biobanks and about the role of genome-based biobanking for epidemiological research and public health is still at the beginning. The following article contributes to this discussion by focusing on the use of genome-based biobanking for epidemiological research, surveillance systems, health policy development, individual health information management and effective health services.
Biobanking for Interdisciplinary Clinical Research
Authors: Riegman P.H.J. , Dinjens W.N.M. , Oosterhuis J.W.
Published: August 2007

Biobanking nowadays is mostly strongly determined by the specific aims of a research group in charge of the biobank, determining their own standards for the collection and annotation of samples. Often a long period is needed to build up the sample and data collections, especially when long-term follow-up data is required. Such collections need a long-term dedication and proper funding. Neglecting either sample number or annotation can result in insignificant or poor results. However, outcome of translational research does not only depend on the sample quality. In many cases it can also be improved to start the experimental design within a multidisciplinary team composed of clinicians including pathologists, molecular biologists, statisticians, bioinformaticians and tissue resource managers. Such a team, capable of careful evaluation of the numbers needed and which or what part of the samples are to be included, could help in obtaining far better results. Many lines of clinical research could benefit more efficiently from the wealth of information stored in well-preserved disease-oriented tissue sample collections with the proper annotations, when the infrastructure around biobanks and new collection build-up is well organized, standardized and streamlined. Future medical research will refine its scientific questions, demanding even further refinement of corresponding clinical information. In addition, larger sample collections are needed to study for instance multifactorial diseases. Today, the samples are collected for tomorrow, therefore, improvement is needed now in standardization, automated enrichment of annotations from hospital information systems and disease registries, insight in overlapping collections of different forms of tissue banking and cooperation in national and international networks.
Tumour Banking: The Spanish Design
Authors: Morente M.M. , de Alava E. , Fernández P.L.
Published: August 2007

In the last decade the technical advances in high throughput techniques to analyze DNA, RNA and proteins have had a potential major impact on prevention, diagnosis, prognosis and treatment of many human diseases. Key pieces in this process, mainly thinking about the future, are tumour banks and tumour bank networks. To face these challenges, diverse suitable models and designs can be developed. The current article presents the development of a nationwide design of tumour banks in Spain based on a network of networks, specially focusing on its harmonization efforts mainly regarding technical procedures, ethical requirements, unified quality control policy and unique sample identification. We also describe our most important goals for the next years. This model does not correspond to a central tumour bank, but to a cooperative and coordinated network of national and regional networks. Independently from the network in which it is included, sample collections reside in their original institution, where it can be used for further clinical diagnosis, teaching and research activities of each independent hospital. The herein described ‘network of networks’ functional model could be useful for other countries and/or international tumour bank activities.
Talking with Families when Their Children Are Dying
Authors: Kuttner Leora
Published: August 2007

Talking with a family whose child is dying is painful and challenging, yet can be a profoundly rewarding aspect of a physician’s work. At some time, every physician must give patients bad news. If this conversation is carried out well, with preparation, compassion, genuine empathy and skill, this adds considerably to the physician’s capacity to provide comprehensive care. Until recently however, there has been little or no training for this sensitive and delicate undertaking. Recent research indicates that breaking bad news to a family is a trainable skill. Data show a high consistency in the desirable traits for good communication. These are compassion, clinical accuracy, honesty, and availability. The literature emphasizes allowing sufficient time in a quiet private setting, following the families’ agenda, using nontechnical language, being emotionally responsive and not doing it alone. Training should include constructive feedback on communication skills, on patient’s perception, addressing interventions, and determining patient’s and caregivers’ support systems. Parental feedback during end-of-life care indicates that maintaining hope, while being honest about what is happening, enables families to cope. Integrating siblings of the dying child is an essential part of successfully talking with the family, as they too carry a heavy burden of grief.
Facilitating Therapeutic Expression and Communication through Play
Authors: Brown Christina D.
Published: August 2007

Objective: To present several examples that illustrate the effectiveness of play interventions in a hospital context facilitated by child life specialists and other health care providers. Clinical Presentation and Intervention: Specific examples include children between the ages of 4 and 10 with serious illnesses (cancer, cystic fibrosis, heart disease) and those having experienced the death of a loved one. Interventions include child-directed play as a therapeutic modality. Conclusion: The opportunities afforded by play and creative arts for self-expression, mastery, and control are of paramount importance for children experiencing the anxiety or psychological trauma often associated with a serious illness or with the death of a loved one.
The Diagnostic Value of Absolute Neutrophil Count, Band Count and Morphologic Changes of Neutrophils in Predicting Bacterial Infections
Authors: Al-Gwaiz Layla A. , Babay Hanan H.
Published: August 2007

Objectives: To evaluate the value of neutrophil left shift parameters and neutrophil morphologic changes in diagnosing acute bacterial infections. Materials and Methods: Peripheral blood samples were obtained from 105 patients who had a positive culture for bacteria. Automated complete white blood cell count was performed as well as peripheral blood smear preparation. Absolute neutrophil count (ANC) and neutrophil band count were determined and the neutrophils were evaluated for morphologic changes, namely toxic granulation, vacuolation and Döhle bodies. Results: Band count was less sensitive than ANC and white blood cell count in predicting bacterial infections except in the elderly and infant population. Toxic granulation in neutrophils appeared to be as sensitive as ANC in predicting bacterial infection. Conclusion: ANC and toxic granulation appear to be more sensitive than band count in predicting bacterial infections. However, band count has a greater sensitivity in infants and elderly patients.
Depressive Symptoms among Kuwaiti Population Attending Primary Healthcare Setting: Prevalence and Influence of Sociodemographic Factors
Authors: Al-Otaibi B. , Al-Weqayyan A. , Taher H. , Sarkhou E. , Gloom A. , Aseeri F. , Al-Mousa E. , Al-Zoubi H. , Habeeba S.
Published: August 2007

Objectives: The aim of this study was to estimate the prevalence of depressive disorders and the influence of sociodemographic characteristics on primary healthcare (PHC) setting in Kuwait. Subjects and Methods: A cross-sectional survey was conducted in PHC setting in Kuwait using the Beck Depression Inventory second edition questionnaire (BDI II) as a screening instrument, together with a sociodemographic questionnaire. A representative sample drawn from the target population consisted of 2,320 subjects of Kuwaiti nationality randomly selected from 18 PHC centers covering all Kuwait governorates during the period from April 2003 to January 2004. The target age group was 21–64 years. Participants were asked to complete the BDI II questionnaire consisting of 21 items reflecting the depressive disorder independently. Sociodemographic data such as sex, age, marital status, children, occupation, educational status, chronic diseases and social problems were included in the questionnaire. The optimum cutoff score for BDI II was estimated. Results: A total of 2,320 participants completed the questionnaire, 1,082 (46.8%) male and 1,237 (53.2%) female; 860 (37.1%) screened positive for depressive symptoms, among whom 352 (15.3%) were male and 508 (21.7%) female. Of all participants, 163 (7.0%) were severely depressed, 314 (13.5%) moderately depressed and 383 (16.5%) mildly depressed. Depressive disorder was more prevalent among women than men, young than old, more among highly educated individuals, working participants, married individuals, and parents with 3 or more children. Conclusion: Depressive disorder is a highly prevalent condition among Kuwaiti patients attending PHC setting. Chronic diseases and social problems are risk factors for depressive disorder.