bluuebunny/crossref_metadata_2025 huggingface dataset:
Central nervous system stimulants and sport practice
Authors: Avois L , Robinson N , Saudan C , Baume N , Mangin P , Saugy M
Published: June 2006

Background and objectives:Central nervous system (CNS) stimulants may be used to reduce tiredness and increase alertness, competitiveness, and aggression. They are more likely to be used in competition but may be used during training to increase the intensity of the training session. There are several potential dangers involving their misuse in contact sports. This paper reviews the three main CNS stimulants, ephedrine, amfetamine, and cocaine, in relation to misuse in sport.

Methods:Description of the pharmacology, actions, and side effects of amfetamine, cocaine, and ephedrine.

Results:CNS stimulants have psychotropic effects that may be perceived to be ergogenic. Some are prescription drugs, such as Ephedra alkaloids, and there are issues regarding their appropriate therapeutic use. Recently attention has been given to their widespread use by athletes, despite the lack of evidence regarding any ergogenic or real performance benefit, and their potentially serious side effects. Recreational drugs, some of which are illegal (cocaine, amfetamines), are commonly used by athletes and cause potential ergolytic effects. Overall, these drugs are important for their frequent use and mention in anti-doping laboratories statistics and the media, and their potentially serious adverse effects.

Conclusions:Doping with CNS stimulants is a real public health problem and all sports authorities should participate in its prevention. Dissemination of information is essential to prevent doping in sport and to provide alternatives. Adequate training and education in this domain should be introduced.
Significance of 19-norandrosterone in athletes’ urine samples
Authors: Ayotte C
Published: June 2006

Nandrolone and other 19-norsteroid potent anabolic steroids have been prohibited in sports for 30 years. The detection of the main urinary metabolite—19-norandrosterone—in amounts greater than 2 ng/ml constitutes an adverse analytical finding. The presence in nutritional sport supplements of steroids not listed on the label has undoubtedly resulted in positive tests, but inadvertent consumption of meat containing residues of hormonal treatment should not realistically cause apprehension. Although highly improbable, athletes should prudently avoid meals composed of pig offal in the hours preceding the test since the consumption of edible parts of a non-castrated pig, containing 19-nortestosterone, has been shown to results in the excretion of 19-norandrosterone in the following hours. Norsteroid metabolites are formed during pregnancy and excreted as minor metabolites of norethisterone, and minute amounts have been identified in some male and female samples when using more sensitive techniques of detection. Whereas exercise does not seem to be a significant factor in 19-norandrosterone excretion, some rare urine samples were found to be a suitable medium for in situ 19-demethylation of urinary metabolites.
Take nothing but pictures, leave nothing but footprints…?
Authors: McCrory P
Published: June 2006

This article has been retracted. See the retraction notice for details. The PDF is retained for transparency.
PRODUCTION–INVENTORY MODEL FOR A DETERIORATING ITEM WITH IMPRECISE PREPARATION TIME FOR PRODUCTION IN A FINITE TIME HORIZON
Authors: MAHAPATRA N. K. , MAITI M.
Published: June 2006

In this paper, realistic production-inventory models with shortages for a deteriorating item with imprecise preparation time for production (hereafter called preparation time) has been formulated and an inventory policy is proposed for maximum profit in a finite time horizon. Here, the rate of production is constant, demand depends on selling price, marketing cost, and inventory level, and setup cost depends on preparation time. The imprecise preparation time is assumed to be represented by a fuzzy number and is first transformed to a corresponding interval number and then following interval mathematics, the objective function for total profit over the finite time horizon is changed to respective multi-objective functions. These functions are maximized and solved for a set of Pareto optimal solution with the help of the weighted sum method using the generalized reduced gradient technique. Different case studies have been made depending upon the occurrence of shortages. The models have been illustrated by numerical data. Pareto-optimal solutions for different weights are obtained and presented in tables and graphs.
GENERALIZED RENEWAL PROCESS (GRP) FOR THE ANALYSIS OF SOFTWARE RELIABILITY GROWTH MODEL
Authors: JAIN MADHU , MAHESHWARI SANDHYA
Published: June 2006

With the rapid advancement in computer technology, the software reliability plays a very significant role in predicting the performance and assuring the quality of the software. A compromise testing effort is necessary to affirm the pre-defined quality of the software at optimum cost by detecting and eliminating errors in the software. In this investigation, a robust solution for software reliability growth model (SRGM) which is applicable to non-perfect repair condition called generalized renewal process (GRP) is proposed. The GRP includes the renewal process (RP) and non-homogeneous Poisson process (NHPP) as special cases by suitable choice of index parameters. The optimal testing time of the software is determined for a large and complex modular software system wherein each module having a different failure rate and other characteristics. Maximum likelihood approach is used to estimate the GRP parameters. Numerical illustrations are provided to explore the effect of various parameters on maintenance cost.
LIMITS ON THE INTEGRATION CONSTANT OF THE DARK RADIATION TERM IN BRANE COSMOLOGY
Authors: AL-RAWAF A. S.
Published: June 2006

We consider the constraints from primordial Helium abundances on the constant of integration of the dark radiation term of the brane-world generalized Friedmann equation derived from the Randall–Sundrum single brane model. We found that — using simple, approximate and semi-analytical methods — the constant of integration is restricted to the range between -9.18 and 5.18 which limits the contribution from dark radiation to be approximately between -28% to 16% of the background photon energy density.
SEARCH FOR SINGLE TOP QUARK PRODUCTION AT DØ
Authors: SCHWIENHORST REINHARD
Published: June 2006

We present a review of searches for electroweak production of single top quarks at the Fermilab Tevatron proton–antiproton collider at [Formula: see text]. Searches for s-channel and t-channel single top quark production have been carried out using secondary-vertex b-quark tagging and advanced event analysis methods in order to maximize the sensitivity to single top quark production. So far, no evidence for a single top quark signal has been found. However, 95% confidence level upper limits on the production cross-section have been set that improve upon previous limits by factors of two to three and are approaching the cross-section region predicted by the standard model.
TRANSLATION INVARIANT RI-SPLINE WAVELET AND ITS APPLICATION ON DE-NOISING
Authors: ZHANG ZHONG , TODA HIROSHI , FUJIWARA HISANAGA , REN FUJI
Published: June 2006

Wavelet Shrinkage using DWT has been widely used in de-noising although DWT has a translation variance problem. In this study, we solve this problem by using the translation invariant DWT. For this purpose, we propose a new complex wavelet, the Real-Imaginary Spline Wavelet (RI-Spline wavelet). We also propose the Coherent Dual-Tree algorithm for the RI-Spline wavelet and extend it to the 2-Dimensional. Then we apply this translation invariant RI-Spline wavelet for translation invariant de-noising. Experimental results show that our method, when applied to ECG data, the medical image and the textile surface inspection can obtain better de-noising results than that of conventional Wavelet Shrinkage.
NETWORKED FACILITIES EXPANSION PROBLEM
Authors: COX LOUIS ANTHONY , BABAYEV DJANGIR A.
Published: June 2006

This paper considers how best to sequence the acquisition of new locations (e.g. office park buildings, multi-tenant units, etc.) to expand the coverage area or fill in the geographic footprint of a network service provider or other business-service activities. Consider several locations, candidates for acquisition, on the plane. Each location will generate a certain revenue stream for the service provider if it is acquired. In addition, once a location has been acquired (i.e. served), it may be less expensive to acquire other nearby locations. The problem addressed in this paper is: Given a finite budget for acquisitions and a model for the acquisition costs, how to sequence the acquisitions to maximize the total new revenue from the locations acquired? A specific cost model is proposed, an integer programming formulation of the problem and its transformations presented. Properties of the models and of the optimal solution are discussed. Finally, an effective heuristic method intended for applications is developed. Features of the solutions are demonstrated by a numerical study.
Downregulation in the expression of the serine dehydratase in the rat liver during chronic metabolic acidosis
Authors: López-Flores Inmaculada , Peragón Juan , Valderrama Raquel , Esteban Francisco J. , Luque Francisco , Peinado M. Ángeles , Aranda Fermín , Lupiáñez José A. , Barroso Juan B.
Published: June 2006

Blood pH controls the activity of important regulatory enzymes in the metabolism. Serine dehydratase (SerDH) transforms l-serine into pyruvate and ammonium and is involved in the regulation of gluconeogenesis from serine in the rat liver. In this work, we investigate the effect of chronic metabolic acidosis on the kinetics, specific protein level, tissue location, and mRNA levels of rat liver SerDH. Experimental acidosis was induced in rats by ingestion of 0.28 M ammonium chloride solution for 10 days. Acidosis significantly ( P < 0.05) decreased SerDH activity at all substrate concentrations assayed. Moreover, the Vmaxvalue was 38.50 ± 3.51 mU/mg ( n = 7) of mitochondrial protein in the acidotic rats and 92.49 ± 6.79 mU/mg ( n = 7) in the control rats. Western blot analysis revealed a significant reduction (14%) in the level of SerDH protein content in the rat liver during acidosis. Immunohistochemical analysis showed that SerDH location did not change in response to chronic metabolic acidosis and confirmed previous results on SerDH protein levels. Moreover, the SerDH mRNA level, estimated by RT-PCR, was also significantly 33.8% lower than in control. These results suggest that during experimental acidosis a specific repression of rat-liver SerDH gene transcription could result, lowering the amount and activity of this enzyme. The changes found in SerDH expression are part of an overall metabolic response of liver to maintain acid-base homeostasis during acidosis.
Modeling baroreflex regulation of heart rate during orthostatic stress
Authors: Olufsen Mette S. , Tran Hien T. , Ottesen Johnny T. , Lipsitz Lewis A. , Novak Vera
Published: June 2006

During orthostatic stress, arterial and cardiopulmonary baroreflexes play a key role in maintaining arterial pressure by regulating heart rate. This study presents a mathematical model that can predict the dynamics of heart rate regulation in response to postural change from sitting to standing. The model uses blood pressure measured in the finger as an input to model heart rate dynamics in response to changes in baroreceptor nerve firing rate, sympathetic and parasympathetic responses, vestibulo-sympathetic reflex, and concentrations of norepinephrine and acetylcholine. We formulate an inverse least squares problem for parameter estimation and successfully demonstrate that our mathematical model can accurately predict heart rate dynamics observed in data obtained from healthy young, healthy elderly, and hypertensive elderly subjects. One of our key findings indicates that, to successfully validate our model against clinical data, it is necessary to include the vestibulo-sympathetic reflex. Furthermore, our model reveals that the transfer between the nerve firing and blood pressure is nonlinear and follows a hysteresis curve. In healthy young people, the hysteresis loop is wide, whereas, in healthy and hypertensive elderly people, the hysteresis loop shifts to higher blood pressure values, and its area is diminished. Finally, for hypertensive elderly people, the hysteresis loop is generally not closed, indicating that, during postural change from sitting to standing, baroreflex modulation does not return to steady state during the first minute of standing.
Exaggerated response to mild stress in rats fed high-fat diet
Authors: Legendre Ariadne , Harris Ruth B. S.
Published: June 2006

It has been suggested that high-fat (HF) diet exaggerates the stress-induced release of glucocorticoids due to activation of the hypothalamic-pituitary-adrenal (HPA) axis. In an initial experiment, in which rats were fed HF diet for 4 days, we found that HF-fed controls stopped gaining weight, indicating that they were hyperresponsive to the mild stress of tail bleeding but responded the same as low-fat (LF)-fed rats to the more severe stress of restraint. A second experiment confirmed these results when rats fed a HF diet for 4 days showed an exaggerated corticosterone release in response to an intraperitoneal injection of saline and movement to a novel cage, compared with LF-fed rats. Experiment 3 tested the same parameters as experiment 2 but interchanged the diets. This allowed us to differentiate between the effects of the dietary fat and the novelty of the diet. Additionally, this experiment determined whether hyperresponsiveness to mild stress in HF-fed rats was sustained during a prolonged exposure to diet. The results confirmed that a HF diet, not novelty, exaggerated the endocrine stress response after 9 days on the diet but that the effect was no longer present after 23 days on the diet. The hyperresponsiveness of the HPA axis in HF-fed rats is similar to that observed in animals that have been exposed to a significant chronic or acute stress, suggesting that the HF diet may initially be perceived as a stressor.
Quantification of cerebrospinal fluid transport across the cribriform plate into lymphatics in rats
Authors: Nagra Gurjit , Koh Lena , Zakharov Andrei , Armstrong Dianna , Johnston Miles
Published: June 2006

A major pathway by which cerebrospinal fluid (CSF) is removed from the cranium is transport through the cribriform plate in association with the olfactory nerves. CSF is then absorbed into lymphatics located in the submucosa of the olfactory epithelium (olfactory turbinates). In an attempt to provide a quantitative measure of this transport,125I-human serum albumin (HSA) was injected into the lateral ventricles of adult Fisher 344 rats. The animals were killed at 10, 20, 30, 40, and 60 min after injection, and tissue samples, including blood (from heart puncture), skeletal muscle, spleen, liver, kidney, and tail were excised for radioactive assessment. The remains were frozen. To sample the olfactory turbinates, angled coronal tissue sections anterior to the cribriform plate were prepared from the frozen heads. The average concentration of125I-HSA was higher in the middle olfactory turbinates than in any other tissue with peak concentrations achieved 30 min after injection. At this point, the recoveries of injected tracer (percent injected dose/g tissue) were 9.4% middle turbinates, 1.6% blood, 0.04% skeletal muscle, 0.2% spleen, 0.3% liver, 0.3% kidney, and 0.09% tail. The current belief that arachnoid projections are responsible for CSF drainage fails to explain some important issues related to the pathogenesis of CSF disorders. The rapid movement of the CSF tracer into the olfactory turbinates further supports a role for lymphatics in CSF absorption and provides the basis of a method to investigate the novel concept that diseases associated with the CSF system may involve impaired lymphatic CSF transport.
Deficiency of γδ T lymphocytes contributes to mortality and immunosuppression in sepsis
Authors: Chung Chun-Shiang , Watkins Lara , Funches Antonio , Lomas-Neira Joanne , Cioffi William G. , Ayala Alfred
Published: June 2006

Studies have indicated that γδ T lymphocytes play an important role in the regulation of immune function and the clearance of intracellular pathogens. We have recently reported that intraepithelial lymphocytes (IEL), which are rich in γδ T cells, within the small intestine illustrated a significant increase in apoptosis and immune dysfunction in mice subjected to sepsis. However, the contribution of γδ T cells to the host response to polymicrobial sepsis remains unclear. In this study, we initially observed that after sepsis induced by cecal ligation and puncture (CLP), there was an increase in small intestinal IEL CD8+γδ+T cells in control γδ+/+mice. Importantly, we subsequently found an increased early mortality in mice lacking γδ T cells (γδ−/−mice) after sepsis. This was associated with decreases in plasma TNF-α, IL-6, and IL-12 levels in γδ−/−mice compared with γδ+/+mice after sepsis. In addition, even though in vitro LPS-stimulated peritoneal macrophages showed a reduction in IL-6 and IL-12 release after CLP, these cytokines were less suppressed in macrophages isolated from γδ−/−mice. Alternatively, IL-10 release was not different between septic γδ+/+and γδ−/−mice. Whereas T helper (Th)1 cytokine release by anti-CD3-stimulated splenocytes was significantly depressed in septic γδ+/+mice, there was no such depression in γδ−/−mice. However, γδ T cell deficiency had no effect on Th2 cytokine release. These findings suggest that γδ T cells may play a critical role in regulating the host immune response and survival to sepsis, in part by alteration of the level of IEL CD8+γδ+T cells and through the development of the Th1 response.
RS1 (RSC1A1) regulates the exocytotic pathway of Na+-d-glucose cotransporter SGLT1
Authors: Veyhl Maike , Keller Thorsten , Gorboulev Valentin , Vernaleken Alexandra , Koepsell Hermann
Published: June 2006

The product of gene RSC1A1, named RS1, participates in transcriptional and posttranscriptional regulation of the sodium-d-glucose cotransporter SGLT1. Using coexpression in oocytes of Xenopus laevis, posttranscriptional inhibition of human SGLT1 (hSGLT1) and some other transporters by human RS1 (hRS1) was demonstrated previously. In the present study, histidine-tagged hRS1 was expressed in oocytes or Sf9 cells and purified using nickel(II)-charged nitrilotriacetic acid-agarose. hRS1 protein was injected into oocytes expressing hSGLT1 or the human organic cation transporter hOCT2, and the effect on hSGLT1-mediated uptake of methyl-α-d-[14C]glucopyranoside ([14C]AMG) or hOCT2-mediated uptake of [14C]tetraethylammonium ([14C]TEA) was measured. Within 30 min after the injection of hRS1 protein, hSGLT1-expressed AMG uptake or hOCT2-expressed TEA uptake was inhibited by ∼50%. Inhibition of AMG uptake was decreased when a dominant negative mutant of dynamin I was coexpressed and increased after stimulation of PKC. Inhibition remained unaltered when endocytosis was inhibited by chlorpromazine, imipramine, or filipin but was prevented when exocytosis was inhibited by botulinum toxin B or when the release of vesicles from the TGN and endosomes was inhibited by brefeldin A. Inhibition of hSGLT1-mediated AMG uptake and hOCT2-mediated TEA uptake by hRS1 protein were decreased at an enhanced intracellular AMG concentration. The data suggest that hRS1 protein exhibits glucose-dependent, short-term inhibition of hSGLT1 and hOCT2 by inhibiting the release of vesicles from the trans-Golgi network.
Oxidative stress and glomerular filtration barrier injury: role of the renin-angiotensin system in the Ren2 transgenic rat
Authors: Whaley-Connell Adam T. , Chowdhury Nazif A. , Hayden Melvin R. , Stump Craig S. , Habibi Javad , Wiedmeyer Charles E. , Gallagher Patricia E. , Ann Tallant E. , Cooper Shawna A. , Link C. Daniel , Ferrario Carlos , Sowers James R.
Published: June 2006

TG(mRen2)27 (Ren2) transgenic rats overexpress the mouse renin gene, manifest hypertension, and exhibit increased tissue ANG II levels and oxidative stress. Evidence indicates that elevated tissue ANG II contributes to oxidative stress, increases in glomerular macromolecular permeability, and consequent albuminuria. Furthermore, angiotensin type 1 receptor (AT1R) blockers reduce albuminuria and slow progression of renal disease. However, it is not known whether improvements in glomerular filtration barrier integrity and albuminuria during treatment are related to reductions in oxidative stress and/or kidney renin-angiotensin system (RAS) activity. To investigate the renal protective effects of AT1R blockade, we treated young (6–7 wk old) male Ren2 rats with valsartan (Ren2-V; 30 mg/kg) for 3 wk and measured urine albumin, kidney malondialdehyde (MDA), RAS component mRNAs, and NADPH oxidase subunits (gp91phoxand Rac1) compared with age-matched untreated Ren2 and Sprague-Dawley (S-D) rats. Basement membrane thickness, slit pore diameter and number, and foot process base width were measured by transmission electron microscopy (TEM). Results indicate that AT1R blockade lowered systolic blood pressure (30%), albuminuria (91%), and kidney MDA (80%) in Ren2-V compared with untreated Ren2 rats. Increased slit pore number and diameter and reductions in basement membrane thickness and podocyte foot process base width were strongly associated with albuminuria and significantly improved following AT1R blockade. AT1R blockade was also associated with increased angiotensin-converting enzyme-2 and neprilysin expression, demonstrating a beneficial shift in balance of renal RAS. Thus reductions in blood pressure, albuminuria, and tissue oxidative stress with AT1R blockade were associated with improved indexes of glomerular filtration barrier integrity and renal RAS in Ren2 rats.
The mRNA expression profile of metabolic genes relative to MHC isoform pattern in human skeletal muscles
Authors: Plomgaard Peter , Penkowa Milena , Leick Lotte , Pedersen Bente K. , Saltin Bengt , Pilegaard Henriette
Published: June 2006

The metabolic profile of rodent muscle is generally reflected in the myosin heavy chain (MHC) fiber-type composition. The present study was conducted to test the hypothesis that metabolic gene expression is not tightly coupled with MHC fiber-type composition for all genes in human skeletal muscle. Triceps brachii, vastus lateralis quadriceps, and soleus muscle biopsies were obtained from normally physically active, healthy, young male volunteers, because these muscles are characterized by different fiber-type compositions. As expected, citrate synthase and 3-hydroxyacyl dehydrogenase activity was more than twofold higher in soleus and vastus than in triceps. Contrary, phosphofructokinase and total lactate dehydrogenase (LDH) activity was approximately three- and twofold higher in triceps than in both soleus and vastus. Expression of metabolic genes was assessed by determining the mRNA content of a broad range of metabolic genes. The triceps muscle had two- to fivefold higher MHC IIa, phosphofructokinase, and LDH A mRNA content and two- to fourfold lower MHC I, lipoprotein lipase, CD36, hormone-sensitive lipase, and LDH B and hexokinase II mRNA than vastus lateralis or soleus. Interestingly, such mRNA differences were not evident for any of the genes encoding mitochondrial oxidative proteins, 3-hydroxyacyl dehydrogenase, carnitine palmitoyl transferase I, citrate synthase, α-ketogluterate dehydrogenase, and cytochrome c, nor for the transcriptional regulators peroxisome proliferator activator receptor gamma coactivator-1α, forkhead box O1, or peroxisome proliferator activator receptor-α. Thus the mRNA expression of genes encoding mitochondrial proteins and transcriptional regulators does not seem to be fiber type specific as the genes encoding glycolytic and lipid metabolism genes, which suggests that basal mRNA regulation of genes encoding mitochondrial proteins does not match the wide differences in mitochondrial content of these muscles.
Reversibility of exercise-induced dendritic attenuation in brain cardiorespiratory and locomotor areas following exercise detraining
Authors: Nelson Amanda J. , Iwamoto Gary A.
Published: June 2006

It has been shown previously that dendritic branching in cardiorespiratory and locomotor brain areas can be attenuated with exercise training (ET). It was not known whether this process was reversible. Twenty-three ( n = 23) male Sprague-Dawley rats were individually caged and divided into two groups: untrained (UN; n = 11) and detrained (DTR; n = 12). DTR were provided with a running wheel at 21 days of age and exercised spontaneously. After 120 days (70 days of ET followed by 50 days of detraining), ET indexes were obtained, including maximal oxygen uptake, percent body fat, resting heart rate, and heart weight-to-body weight ratios. The brain was processed according to a modified Golgi-Cox procedure. Impregnated neurons from the periaqueductal gray (PAG), posterior hypothalamic area (PH), nucleus of the tractus solitarius (NTS), and cuneiform nucleus (CfN) were examined in coronal sections. Neurons were traced using a camera lucida technique and analyzed using the Sholl concentric ring analysis of dendritic branching. t-Tests compared the mean number of intersections per neuron by grouping inner rings, outer rings, and total number of intersections per animal. There were no significant differences between UN and DTR in PH, PAG, CfN, and NTS in the inner rings, outer rings, and total number of intersections per animal. A separate group of animals was used to show that a training effect in the CfN and NTS was present at 56 days of ET. Our results show that dendritic attenuation resulting from 70 days of ET in PH, PAG, CfN, and NTS is completely reversed with 50 days of detraining.
Changes in tissue water content measured with multiple-frequency bioimpedance and metabolism measured with 31P-MRS during progressive forearm exercise
Authors: Raja Mohan K. , Raymer Graydon H. , Moran Gerald R. , Marsh Greg , Thompson R. Terry
Published: June 2006

Multiple-frequency bioimpedance analysis (MFBIA) has been used to determine the cellular water composition in the human body. It is noninvasive and has demonstrated good correlations with other invasive measures of tissue water. However, the ability of this method to study transient changes in tissue water in specific muscle groups has not been explored. In this study, MFBIA was used to assess changes in forearm intracellular water (ICW), extracellular water (ECW), and total water (TW) in seven healthy volunteers during and after a progressive wrist flexion exercise protocol. In an identical trial, 31P magnetic resonance spectroscopy (31P-MRS) was used to assess changes in intracellular pH and phosphocreatine (PCr). At the completion of exercise, forearm ICW increased 12.6% (SD 0.07, P = 0.003), TW increased 10.1% (SD 0.06, P = 0.005), and no significant changes were recorded for ECW. A significant correlation was found between the changes in intracellular pH and changes in ICW during exercise ( r = −0.84, P = 0.018). With the use of regression analysis, average changes in Pi, PCr, and pH were found to predict changes in ICW ( R2 = 0.98, P = 0.005). In conclusion, MFBIA was sensitive enough to measure transient changes in the exercising forearm muscle. The changes seen were consistent with the hypothesis that intracellular acidification and PCr hydrolysis are important mediators of cellular osmolality and therefore may be responsible for the increased volume of water in the intracellular space that is often recorded after short-term high-intensity exercise.
Wavelet analysis of scaling properties of gastric electrical activity
Authors: West Bruce J. , Maciejewski Artur , Latka Miroslaw , Sebzda Tadeusz , Swierczynski Zbigniew , Cybulska-Okołow Sylwia , Baran Eugeniusz
Published: June 2006

We present a novel approach to the analysis of fluctuations in human myoelectrical gastric activity measured noninvasively from the surface of the abdomen. The time intervals between successive maxima of the wavelet transformed quasi-periodic electrogastrographic waveform define the gastric rate variability (GRV) time series. By using the method of average wavelet coefficients, the statistical fluctuations in the GRV signal in healthy individuals are determined to scale in time. Such scaling was previously found in a variety of physiological phenomena, all of which support the hypothesis that physiological dynamics utilize fractal time series. We determine the scaling index in a cohort of 17 healthy individuals to be 0.80 ± 0.14, which compared with a set of surrogate data is found to be significant at the level P < 0.01. We also determined that the dynamical pattern, so evident in the spectrum of average wavelet coefficients of the GRV time series of healthy individuals, is significantly reduced in a cohort of systemic sclerosis patients having a scaling index 0.64 ± 0.17. These results imply that the long-term memory in GRV time series is significantly reduced from healthy individuals to those with systemic sclerosis. Consequently, this disease degrades the complexity of the underlying gastrointestinal control system and this degradation is manifest in the loss of scaling in the GRV time series.
Implications of Functionally Different Synaptic Inputs for Neuronal Gain and Computational Properties of Fly Visual Interneurons
Authors: Grewe Jan , Matos Nélia , Egelhaaf Martin , Warzecha Anne-Kathrin
Published: June 2006

Neurons embedded in networks are thought to receive synaptic inputs that do not drive them on their own, but modulate the responsiveness to driving input. Although studies on brain slices have led to detailed knowledge of how nondriving input affects dendritic integration, its origin and functional implications remain unclear. We tackle this issue using an ensemble of fly wide-field visual interneurons. These neurons offer the opportunity not only to combine in vivo recording techniques and natural sensory stimulation but also to interpret electrophysiological results in a behavioral context. By targeted manipulation of the animal's visual input we find a pronounced modulating impact of nondriving input, whereas functionally important cellular properties like direction tuning and the coding of pattern velocity are left almost unaffected. We propose that the integration of functionally different synaptic inputs is a mechanism that immanently equalizes the ensemble's sensitivity irrespective of the specific stimulus conditions.
Assessment of the Value of Rescreening for Syphilis in the Third Trimester of Pregnancy
Authors: Edwards Rodney K. , Bennett Margaret , Langstraat Carrie , Greene Daina
Published: June 2006

Objectives. Our aim is evaluating the need for repeating tests for syphilis on pregnant women in the third trimester. Study design. A single‐center retrospective cohort study was performed on all women delivering 7/03–6/04. Results. During the study interval, 2244 women delivered at our hospital. Of those women having available records and attending at least one prenatal visit, 1940 (98.9%) were screened for syphilis at the first prenatal visit. Of the 1627 women beginning prenatal care prior to 27 weeks and delivering after 32 weeks, 1377 (84.6%) were rescreened in the third trimester. No cases of syphilis were identified with either the initial (upper limit of 95% CI 0.24%) or repeat (upper limit of 95% CI 0.34%) screening. Conclusions. In our obstetric population, syphilis is so uncommon that mandated prenatal screening on more than one occasion seems unjustified and laws requiring repeated screening should be reevaluated.
Hepatic Dysfunction in Typhoid Fever During Pregnancy
Authors: H. Jorge Hasbun , Osorio Raúl , Hasbun Andrea
Published: June 2006

We described the hepatic dysfunction found in 10 cases out of 32 women with typhoid fever during pregnancy. This was associated with late diagnosis and maternal and perinatal complications.
Differential Predictors of Response to Preventive Cognitive Therapy in Recurrent Depression: A 2-Year Prospective Study
Authors: Bockting Claudi L.H. , Spinhoven Philip , Koeter Maarten W.J. , Wouters Luuk F. , Visser Ieke , Schene Aart H.
Published: June 2006

Background:Major depressive disorder is a recurrent disease. Brief cognitive therapy (CT), added to either regular care or medication, is helpful in preventing relapse/recurrence. Little is known which type of persons benefit from preventive CT, the so called ‘aptitude treatment interaction’ effect. Method:The present cohort included exclusively patients with at least two previous episodes remitted on various types of treatments (n = 172). They were assessed within a clinical trial comparing treatment as usual (TAU) with preventive CT added to TAU. Differential demographic, illness-related, psychological and biological risk factors in postponing recurrence by preventive CT were examined. Results:Significant aptitude-treatment-interaction effects were found for the number of previous episodes, daily hassles and life events, avoidant coping, gender, and morning cortisol levels. Preventive CT seemed ineffective in patients with life events (as more frequently reported by women in our study) and in patients with high episode number characterized by higher levels of avoidant coping. Generic predictors indicate that in CT, as in TAU, patients with more residual depressive symptomatology and higher levels of dysfunctional attitudes profit less from preventive CT. Conclusion:The finding that preventive CT protects against the influence of a consistently found risk factor of relapse/recurrence, i.e. the number of depressive episodes, underlines the potential of psychological preventive interventions. Preventive CT seemed to be especially effective in reducing presumably internally provoked, relapse/recurrence but may be quite ineffective in reducing externally provoked relapse/recurrence. CT possibly prevents either stress generation or disrupts kindling effects. Kindling effects probably cannot be disrupted in patients with higher levels of avoidant coping who experienced a high number of episodes, and patients who experienced life events.
Effects of Electromagnetic Fields on Cells: Physiological and Therapeutical Approaches and Molecular Mechanisms of Interaction
Authors: Funk Richard H.W. , Monsees Thomas K.
Published: June 2006

This review concentrates on findings described in the recent literature on the response of cells and tissues to electromagnetic fields (EMF). Models of the causal interaction between different forms of EMF and ions or biomolecules of the cell will be presented together with our own results in cell surface recognition. Naturally occurring electric fields are not only important for cell-surface interactions but are also pivotal for the normal development of the organism and its physiological functions. A further goal of this review is to bridge the gap between recent cell biological studies (which, indeed, show new data of EMF actions) and aspects of EMF-based therapy, e.g., in wounds and bone fractures.
Renal Angiotensin Receptor Type 1 and 2 Upregulation in Intrauterine Growth Restriction of Newborn Piglets
Authors: Rüster Michael , Sommer Manfred , Stein Günter , Bauer Kathrin , Walter Bernd , Wolf Gunter , Bauer Reinhard
Published: June 2006

Epidemiological and experimental studies suggest that intrauterine growth restriction (IUGR) is associated with abnormalities in kidney development which is thought to be linked with alterations causing adult cardiovascular diseases. The renin-angiotensin system (RAS) plays an important role in the development of renal vascular and tubular structures, and is known to be altered by experimentally induced IUGR. These experimental models of IGUR have been criticized because they may have a more severe impact on intrauterine development than that which is normally encountered in humans. Therefore, we asked whether naturally occurring small-for-gestational-age newborn piglets exhibit features of altered RAS activity. We investigated the regional renal expression of angiotensin II type 1 (AT1) and AT2 receptors in normal-weight and IUGR piglets. The AT1 receptor mRNA expression was markedly enhanced in IUGR piglets, in the renal cortex by 64% and in the renal medulla by 52% (p < 0.05, compared with normal littermates). In contrast, mRNA expression for the AT2 receptor was similar in both the normal-weight and IUGR piglets. A significantly higher AT1 receptor protein expression was found in the IUGR piglets (p < 0.05) in the glomeruli, in the proximal and distal tubules, as well as in the collecting ducts by immunohistochemistry. Furthermore, AT2 receptor protein expression was significantly higher in the IUGR piglets (p < 0.05) in the subcapsular nephrogenic zone and in the distal tubules and collecting ducts. Thus, IUGR is accompanied by an upregulation of angiotensin II receptor expression in the kidneys of newborn piglets. This may indicate an alteration of the RAS in newborns suffering from naturally occurring IUGR.
The Relationship of Microalbuminuria with Metabolic Syndrome
Authors: Choi Hyo Sun , Ryu Seung Ho , Lee Kyu-Beck
Published: June 2006

Background/Aims: Microalbuminuria and the metabolic syndrome are risk factors for cardiovascular disease. The aim of this study is to examine the prevalence of microalbuminuira and to document the relationship of microalbuminuria with the metabolic syndrome in a large population of Korean subjects. Methods: We examined the cross-sectional association of microalbuminuria with the components of the metabolic syndrome and with other cardiovascular risk factors in 6,588 Korean adults who took part in a health examination program. Results: The prevalence of microalbuminuria was 4.2% in the non-metabolic syndrome group (n = 5,902), and 14.4% in the metabolic syndrome group (n = 686). The odds ratio of microalbuminuria in the adults with the metabolic syndrome compared with those adults without the metabolic syndrome was 1.53 (1.13–2.07 95% CI). In the multiple logistic regression analysis, as compared with the subjects without an elevated blood pressure, a low high-density lipoprotein cholesterol level, a high triglyceride level, a high plasma glucose level and a large waist circumference, the odds ratios for microalbuminuria with these components, after adjustment was made for the body mass index, the high-sensitivity C-reactive protein level and the homeostasis model assessment, were 2.17 (95% CI 1.71–2.76), 2.84 (95% CI 1.55–5.21), 1.30 (95% CI 1.03–1.65) and 2.68 (95% CI 2.04–3.51), respectively. The corresponding multivariate-adjusted odds ratios of microalbuminuria for the participants with 1, 2, 3, and 4 and 5 components of metabolic syndrome were 1.79 (95% CI 1.24–2.59), 2.35 (95% CI 1.58–3.51), 3.23 (95% CI 2.07–5.25), and 4.22 (95% CI 2.13–8.35), respectively. Conclusion: There was a significantly graded relationship between the number of metabolic syndrome components and the corresponding prevalence of microalbuminuria. These findings suggest microalbuminuria is strongly related with the components of the metabolic syndrome.
Recent Insights into Experimental Mouse Models of Diabetic Nephropathy
Authors: Tesch Gregory H. , Nikolic-Paterson David J.
Published: June 2006

Background/Aims: Mouse models are an essential experimental tool for investigating the role of molecular mechanisms and genetic susceptibility in the development of diabetic nephropathy. Methods: The most widely used inbred strain, the C57BL/6 mouse, is commonly used in streptozotocin-induced models of type 1 diabetes and is particularly susceptible to obesity-induced type 2 diabetes. However, use of this strain has been criticised by studies suggesting that it is relatively resistant to renal injury. Results: Recent refinement of these models and utilisation of genetically modified (knockout and transgenic) mice on a C57BL/6 background has provided important insights into the roles of oxidative stress, advanced glycation end products, inflammation and profibrotic mechanisms in the development of type 1 and type 2 diabetic nephropathy. Conclusion: These findings demonstrate the utility of mouse models for identifying and testing novel therapeutic strategies which could translate into better protection against the human disease.
Analbuminemic Nagase Rats: Blood Pressure Response to Dietary Salt Challenge
Authors: Yu Zhenrong , Schumacher Martin , Dick Bernhard , Frey Felix J. , Frey Brigitte M. , Vogt Bruno
Published: June 2006

Background: The role of albumin on blood pressure response to different salt challenges is not known. Therefore, we studied the blood pressure response of analbuminemic Nagase rats (NAR) to different salt challenges. 11β-Hydroxysteroid dehydrogenase type 2 (11β-HSD2), the enzyme regulating the glucocorticoid access to the mineralocorticoid receptor, an enzyme that is decreased in humans with salt sensitive hypertension and other diseases with abnormal renal salt retention, was assessed during salt challenges. Methods: Blood pressure was measured continuously by an intra-arterial catheter and a telemetry system in NAR (n = 8). NAR were set successively for 7 days on a normal (0.45% NaCl), high (8% NaCl), low (0.1% NaCl) and normal salt diet again, to assess salt related response in mean systolic (SBP) and diastolic blood pressure (DBP). 11β-HSD2activity was assessed by measuring the urinary (THB + 5α-THB)/THA ratio with gas chromatography – mass spectrometry. Results: Mean SBP and DBP increased with high salt intake (normal salt vs. high salt: SBP: 114 ± 1 vs.119 ± 3 mm Hg, p < 0.01; DBP: 84 ± 1 vs. 88 ± 3 mm Hg; n = 8; p < 0.01). Urinary (THB +5α-THB)/THA ratio increased during the high-salt period when compared to the normal-salt period (high salt vs. normal salt: 0.52 ± 0.10 vs. 0.37 ± 0.07; p = 0.05) indicating decreased 11β-HSD2activity. Conclusion: Analbuminemic Nagase rats express increased blood pressure and reduced 11β-HSD2 activity in response to a high-salt diet.
Primary Repair of Esophageal Atresia in Extremely Low Birth Weight Infants: A Single-Center Experience and Review of the Literature
Authors: Seitz Guido , Warmann Steven W. , Schaefer Juergen , Poets Christian F. , Fuchs Joerg
Published: June 2006

Background: Advances in neonatal intensive care have led to an increased survival of very low birth weight (VLBW, <1,500 g) and extremely low birth weight infants (ELBW, <1,000 g). Several abnormalities may occur in these children, e.g. esophageal atresia (EA), imperforate anus or abdominal wall defects. Correction of EA is often performed as a staged procedure in this group of patients. Objectives: To evaluate the feasibility of a primary correction of EA in 4 ELBW and VLBW infants. Methods: Between 2002 and 2004, 4 infants below 1,200 g were operated on in our institution with a diagnosis of EA with lower tracheoesophageal fistula. Birth weight ranged from 780 to 1,120 g (median: 920 g), gestational age from 28 to 30 weeks. Treatment included closure of the tracheoesophageal fistula and primary anastomosis of the esophagus in a one-step procedure. Results: Primary correction of EA and fistula repair was feasible in all children. Initially, all children had a normal passage of the esophagus as observed in barium swallowing. One child suffering from a leakage of the anastomosis was managed conservatively. Another infant suffered from spontaneous small bowel perforation 6 days after surgery, which was treated by laparotomy. One child developed stenosis of the esophagus and required a single dilatation 14 months after initial treatment. In the 4th child, a type II cleft syndrome was subsequently diagnosed, requiring secondary cleft repair together with semifundoplication. This child eventually died from cytomegalovirus pneumonia. Conclusions: Primary repair of EA and closure of a tracheoesophageal fistula is technically feasible and offers a good treatment option for ELBW and VLBW infants. Staged repair can be avoided. Infants with cleft syndrome are still a diagnostic and therapeutic challenge.
Cochleovestibular Dysfunction in Ankylosing Spondylitis
Authors: Erbek Selim S. , Erbek H. Seyra , Yilmaz Sema , Topal Ozgul , Yucel Eftal , Ozluoglu Levent N.
Published: June 2006

Ankylosing spondylitis (AS) is a rheumatic disease characterized by chronic inflammation. The aim of this study was to evaluate the functions of the cochlea and the vestibular system in patients with AS. The study group consisted of 32 patients with AS and 30 healthy volunteers as a control group. Otorhinolaryngologic examinations were performed in all patients together with pure-tone audiometry, speech tests, impedancemetry, transient evoked otoacoustic emission (TEOAE) and electronystagmography (ENG). A significant difference was found between the 2 groups with regard to pure-tone averages at high frequencies in each ear (p < 0.05). The rates of reproducibility in TEOAE testing were significantly lower in patients with AS (p = 0.03). The signal-to-noise rates of the response values were lower at all frequencies in patients with AS, but a statistically significant difference was only observed at 2, 3 and 4 Hz (p < 0.05). ENG revealed pathologies in 11 patients with AS (34%), 8 of which were central (25%) and 3 of which were peripheral (9%). No correlation was found between cochleovestibular dysfunction and age, sex, disease duration, activity and medication taken. This study demonstrated that there is an association between AS and cochleovestibular dysfunction.
A Simple Parallel Analytical Method of Prenatal Screening
Authors: Li Ding , Yang Hao , Zhang Wen-Hong , Pan Hao , Wen Dong-Qing , Han Feng-Chan , Guo Hui-Fang , Wang Xiao-Ming , Yan Xiao-Jun
Published: June 2006

Protein microarray has progressed rapidly in the past few years, but it is still hard to popularize it in many developing countries or small hospitals owing to the technical expertise required in practice. We developed a cheap and easy-to-use protein microarray based on dot immunogold filtration assay for parallel analysis of ToRCH-related antibodies including Toxoplasma gondii, rubella virus, cytomegalovirus and herpes simplex virus type 1 and 2 in sera of pregnant women. It does not require any expensive instruments and the assay results can be clearly recognized by the naked eye. We analyzed 186 random sera of outpatients at the gynecological department with our microarray and commercial ELISA kit, and the results showed there was no significant difference between the two detection methods. Validated by clinical application, the microarray is easy to use and has a unique advantage in cost and time. It is more suitable for mass prenatal screening or epidemiological screening than the ELISA format.