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Kinds of Increase Terms modified by Increase Selected AbstractsSALES MAXIMIZATION AND PROFIT MAXIMIZATION: A NOTE ON THE DECISION OF A SALES MAXIMIZER TO THE INCREASE OF PER UNIT COSTPACIFIC ECONOMIC REVIEW, Issue 5 2007Ke Li A common mistake in currently used textbooks is pointed out, and a new proposition is proposed for replacing a false statement there. [source] FORMALIN-INDUCED INCREASE IN P2X3 RECEPTOR EXPRESSION IN DORSAL ROOT GANGLIA: IMPLICATIONS FOR NOCICEPTIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2009Ai-Hua Pan SUMMARY 1ATP-gated P2X receptors in nociceptive sensory neurons participate in the transmission of pain signals from the periphery to the spinal cord. The effect of formalin on the expression of P2X3 receptors in dorsal root ganglia (DRG) was characterized using molecular and immunological approaches and the patch-clamp technique. 2Adult Sprague-Dawley rats were injected with 100 µL of 5% formalin in the planar surface of the hindpaw and were killed 30 min and 1, 3, 6, 12, 24 and 48 h later for in vitro analyses. The expression and distribution of P2X3 receptors in the lumbar spinal cord and in L5/L6 DRG were examined; 24 and 48 h after formalin injection, currents in neurons were examined using whole-cell patch-clamp recording. 3Western blots showed that anti-P2X3 antibody recognized a major monomer of approximately 64 kDa in DRG. Immunoreactivity for P2X3 receptors was detected predominantly in the cytoplasm and plasma membrane of small (< 25 µm) and middle-sized (25,50 µm) DRG neurons. Expression of the P2X3 transcript in the DRG was unchanged 30 min and 1 h after formalin injection, but increased after 12 h. There was no distinct change in P2X3 immunostaining of the spinal cord lamina at 30 min or 1 h after injection, but after 24 h P2X3 labelling increased. At 24 h after the formalin injection, currents in isolated small and middle-sized DRG neurons were increased by 1 µmol/L ,,,-methylene-ATP. These currents were completely inhibited by 1 µmol/L A-317491, a potent and selective P2X3 receptor antagonist. 4These data suggest that formalin injection leads to early upregulation of P2X3 expression in the spinal cord and DRG and that this may be one of the mechanisms giving rise to nociception. [source] Myocardial growth before and after birth: clinical implications,ACTA PAEDIATRICA, Issue 2 2000AM Rudolph Perinatal changes in myocardial growth have recently evoked considerable interest with regard to cardiac chamber development with congenital cardiac lesions and to myocardial development in preterm infants. It is suggested that cardiac chamber development is influenced by blood flow. Experimental pulmonary stenosis in fetal lambs may induce either greatly reduced or markedly increased right ventricular volume. Ventricular enlargement appears to be associated with a large ventricular volume load resulting from tricuspid valve regurgitation. A small competent tricuspid valve is associated with reduced flow through the ventricle due to outflow obstruction and a small right ventricle. Postnatal growth of the ventricles in congenital heart disease is discussed. Increase in myocardial mass prenatally is achieved by hyperplasia, both during normal development and when myocardial mass is increased by right ventricular outflow obstruction. Postnatally, increases in myocardial mass with normal growth, as well as with ventricular outflow obstruction, are largely due to hypertrophy of myocytes. Myocardial capillary numbers do not increase in proportion with myocyte numbers in ventricular myocardium in association with outflow obstruction. The postnatal effects of these changes in congenital heart lesions are considered. Studies in fetal lambs suggest that the late gestational increase in blood cortisol concentrations is responsible for the change in the pattern of myocardial growth after birth. The concern is raised that prenatal exposure of the premature infant to glucocorticoids, administered to the mother to attempt to prevent hyaline membrane disease in the infant, may inhibit myocyte proliferation and result in a heart with fewer than normal myocytes. This would necessitate that each myocyte would have to hypertrophy abnormally to achieve a normal cardiac mass postnatally. [source] Gravitational unloading inhibits the regenerative potential of atrophied soleus muscle in miceACTA PHYSIOLOGICA, Issue 3 2009Y. Matsuba Abstract Aim:, The present study was performed to investigate the influence of unloading on the regeneration of atrophied and injured skeletal muscle. Methods:, Male mice (C57BL/6J), aged 8 weeks, were used. Cardiotoxin (CTX) was injected into soleus muscles bilaterally. Gravitational unloading on soleus muscle was performed by hind limb suspension for 2 weeks before and additionally 6 weeks after CTX injection in one group. Soleus muscles in the remaining groups were loaded keeping the mice in the cages and were dissected 14, 28 and 42 days after the injection. Results:, Recovery of the wet weight and protein content of soleus in the CTX-injected group was inhibited by unloading. Increase in satellite cell number, induced by CTX injection and loading, was also inhibited by unloading. Disappearance of infiltration of mononucleated cells into the necrotic area was also delayed. This phenomenon suggests that regeneration, which is indicated by the appearance of fibres with central nuclei, was inhibited by unloading. Conclusion:, Results suggested that loading plays an important role in the activation of the regenerating potential of injured skeletal muscle. [source] Eyelid Tightening and Improved Eyelid Aperture through Nonablative Fractional ResurfacingDERMATOLOGIC SURGERY, Issue 11 2008SEAN A. SUKAL MD BACKGROUND AND OBJECTIVE The effects of fractional resurfacing on eyelid tightening and aperture are unknown. Our purpose was to retrospectively examine the potential for eyelid tightening and eye-aperture opening in patients treated with nonablative fractional resurfacing for facial photorejuvenation. STUDY DESIGN/MATERIALS AND METHODS Fractional laser treatments using a 1,550-nm erbium-doped fiber laser system on the upper and lower eyelids were given at a pulse energy of 17 to 20 mJ at 125 micro-thermal zones (MTZ)/cm2 to a final density of 500 to 750 MTZ/cm2. Each patient had 3 to 7 treatments. Standard pre- and post-treatment photographs were taken at each visit. Physicians who graded 31 preselected patient photographs using a 4-point scale evaluated eyelid tightening. Increase in eyelid aperture was also evaluated. RESULTS All patients had some degree of eyelid tightening; 19% achieved 1% to 25% tightening, 26% achieved 25% to 50%, 26% achieved 50% to 75%, and 29% achieved 75% to 100%. Increase in eyelid aperture was seen in 55.9% of patients. Postoperative wounding, hypopigmentation, hyperpigmentation, persistent erythema, and scarring were not observed. All patients experienced mild or no edema for a few days after treatment. CONCLUSION Fractional resurfacing tightens and increases eyelid aperture without wounding, downtime, or long-term complications. [source] Increase in Surgical Procedures in a Dermatology Department in United KingdomDERMATOLOGIC SURGERY, Issue 5 2006PREETI N. ATHAVALE MRCP No abstract is available for this article. [source] Increase in multidrug transport activity is associated with oocyte maturation in sea stars,DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 9 2006Troy A. Roepke In this study, we report on the presence of efflux transporter activity before oocyte maturation in sea stars and its upregulation after maturation. This activity is similar to the multidrug resistance (MDR) activity mediated by ATP binding cassette (ABC) efflux transporters. In sea star oocytes the efflux activity, as measured by exclusion of calcein-am, increased two-fold 3 h post-maturation. Experiments using specific and non-specific dyes and inhibitors demonstrated that the increase in transporter activity involves an ABCB protein, P-glycoprotein (P-gp), and an ABCC protein similar to the MDR-associated protein (MRP)-like transporters. Western blots using an antibody directed against mammalian P-gp recognized a 45 kDa protein in sea star oocytes that increased in abundance during maturation. An antibody directed against sea urchin ABCC proteins (MRP) recognized three proteins in immature oocytes and two in mature oocytes. Experiments using inhibitors suggest that translation and microtubule function are both required for post-maturation increases in transporter activity. Immunolabeling revealed translocation of stored ABCB proteins to the plasma cell membrane during maturation, and this translocation coincided with increased transport activity. These MDR transporters serve protective roles in oocytes and eggs, as demonstrated by sensitization of the oocytes to the maturation inhibitor, vinblastine, by MRP and PGP-specific transporter inhibitors. [source] Increase of learning abilities and maturation of the vertical lobe complex during postembryonic development in the cuttlefish, SepiaDEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2001Ludovic Dickel Abstract When shown prawns in a glass tube, cuttlefish quickly learn to inhibit their predatory behavior. By using a visual learning paradigm, we studied training and retention performances of cuttlefish aged from 8 to 90 days. We found an improvement in the acquisition of learning abilities during the first 2 months of life as well as an increase of 24-hr retention performance between 30 and 90 days of age. Using morphometric measurements of different lobes of the central nervous system, we correlated the emergence of these learning abilities with the postembryonic development of related nervous structures. Our results show that only the growth of the superior frontal and vertical lobes appears to be significantly correlated with the improvement of learning and long-term retention performances. Thus, as found in earlier data collected in Octopus, the vertical lobe complex of the cuttlefish seems to be involved in these learning processes. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 40: 92,98, 2001 [source] Diabetic neuropathy and oxidative stressDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 4 2006Rodica Pop-Busui Abstract This review will focus on the impact of hyperglycemia-induced oxidative stress in the development of diabetes-related neural dysfunction. Oxidative stress occurs when the balance between the production of reactive oxygen species (ROS) and the ability of cells or tissues to detoxify the free radicals produced during metabolic activity is tilted in the favor of the former. Although hyperglycemia plays a key role in inducing oxidative stress in the diabetic nerve, the contribution of other factors, such as endoneurial hypoxia, transition metal imbalances, and hyperlipidemia have been also suggested. The possible sources for the overproduction of ROS in diabetes are widespread and include enzymatic pathways, auto-oxidation of glucose, and mitochondrial superoxide production. Increase in oxidative stress has clearly been shown to contribute to the pathology of neural and vascular dysfunction in diabetes. Potential therapies for preventing increased oxidative stress in diabetic nerve dysfunction will be discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] A Community Intervention by Firefighters to Increase 911 Calls and Aspirin Use for Chest PainACADEMIC EMERGENCY MEDICINE, Issue 4 2006Hendrika Meischke PhD Abstract Objectives: To test the effectiveness of an intervention, delivered face-to-face by local firefighters, designed to increase utilization of 911 and self-administration of aspirin for seniors experiencing chest pain. Methods: King County, Washington was divided into 126 geographically distinct areas that were randomized to intervention and control areas. A mailing list identified households of seniors within these areas. More than 20,000 homes in the intervention areas were contacted by local firefighters. Data on all 911 calls for chest pain and self-administration of aspirin were collected from the medical incident report form (MIRF). The unit of analysis was the area. Firefighters delivered a heart attack survival kit (that included an aspirin) and counseled participants on the importance of aspirin and 911 use for chest pain. Main outcome measures were 911 calls for chest pain and aspirin ingestion for a chest pain event, obtained from the MIRFs that are collected by emergency medical services personnel for 2 years after the intervention. Results: There were significantly more calls (16%) among seniors on the mailing list in the intervention than control areas in the first year after the intervention. Among the seniors who were not on the mailing list, there was little difference in the intervention and control areas. The results were somewhat sensitive to the analytical model used and to an outlier in the treatment group. Conclusions: A community-based firefighter intervention can be effective in increasing appropriate response to symptoms of a heart attack among elders. [source] Peripheral sensitization in migraine,role for P2X purinergic receptors in the dura,vascular sensory pathwayDRUG DEVELOPMENT RESEARCH, Issue 6 2007Ernest A. Jennings Abstract Peripheral sensitization is still considered a prime contributor underlying the mechanisms of migraine. Trigeminal primary afferent neurons are the first neurons in the dural nociceptive pathway, and activation results in conscious perception of pain. Peripheral sensitization can lower the activation threshold of primary afferent neurons, rendering them more excitable, allowing for increases in release of neurotransmitter from both central and peripheral terminals. Increase in neurotransmitter release from central terminals contributes to excitation of second-order neurons, while the release of peptides from peripheral terminals has been implicated in neurogenic inflammation. Adenosine 5,-triphosphate (ATP) causes pain in human studies, and depolarize sensory neurons. There is evidence of the action of ATP at many levels in the dura,vascular sensory pathway. Animal studies have shown that some P2X receptors are located in neurons innervating the dura, including the P2X3 receptor, which is most often shown to be involved in nociceptive pathways. In this article, we briefly review peripheral sensitization in relation to migraine and provide emphasis for P2X receptor involvement where it is available. Drug Dev Res 68:321,328, 2007. © 2007 Wiley-Liss, Inc. [source] Worsening of Left Ventricular End-Systolic Volume and Mitral Regurgitation without Increase in Left Ventricular Dyssynchrony on Acute Interruption of Cardiac Resynchronization TherapyECHOCARDIOGRAPHY, Issue 7 2009Suman S. Kuppahally M.D. Background: Responders to cardiac resynchronization therapy (CRT) have greater left ventricular (LV) dyssynchrony than nonresponders prior to CRT. Aim: We conducted this study to see whether the long term responders have more worsening of LV dyssynchrony and LV function on acute interruption of CRT. Materials and Methods: We identified 22 responders and 13 nonresponders who received CRT as per standard criteria for 23.73 ± 7.9 months (median 24.5 months). We assessed the acute change in LV function, mitral regurgitation (MR) and compared LV dyssynchrony in CRT on and off modes. Results: On turning off CRT, there was no significant worsening of LV dyssynchrony in both responders and nonresponders. The dyssynchrony measurements by SPWMD, TDI and 3D echocardiography did not correlate significantly. LVESV increased (p = 0.02) and MR (p = 0.01) worsened in CRT-off mode in responders only without significant change in LVEF or LV dimensions. Discussion and Conclusion: In long-term responders to CRT, there is alteration in the function of remodeled LV with acute interruption of CRT, without significant worsening of LV dyssynchrony. The role of different echocardiographic parameters in the assessment of LV dyssynchrony remains controversial. Even after long-term CRT reversely remodels the LV, the therapy needs to be continued uninterrupted for sustained benefits. [source] Increase in Riparian Vegetation along Peterson Creek, North Queensland 1938,2004ECOLOGICAL MANAGEMENT & RESTORATION, Issue 1 2006Amanda N. D. Freeman First page of article [source] Increase of atmospheric CO2 promotes phytoplankton productivityECOLOGY LETTERS, Issue 6 2004Peter Schippers Abstract It is usually thought that unlike terrestrial plants, phytoplankton will not show a significant response to an increase of atmospheric CO2. Here we suggest that this view may be biased by a neglect of the effects of carbon (C) assimilation on the pH and the dissociation of the C species. We show that under eutrophic conditions, productivity may double as a result of doubling of the atmospheric CO2 concentration. Although in practice productivity increase will usually be less, we still predict a productivity increase of up to 40% in marine species with a low affinity for bicarbonate. In eutrophic freshwater systems doubling of atmospheric CO2 may result in an increase of the productivity of more than 50%. Freshwaters with low alkalinity appeared to be very sensitive to atmospheric CO2 elevation. Our results suggest that the aquatic C sink may increase more than expected, and that nuisance phytoplankton blooms may be aggravated at elevated atmospheric CO2 concentrations. [source] Does Correlation Between Stock Returns Really Increase During Turbulent Periods?ECONOMIC NOTES, Issue 1 2001Francois Chesnay Correlations betwen international equity markets are often claimed to increase during periods of high volatility. Therefore the benefits of international diversification are reduced when they are most needed, i.e. during turbulent periods. This paper investigates the relationship between international correlation and stock-market turbulence. We estimate a multivariate Markov-switching model, in which the correlation matrix varies across regimes. Subsequently, we test the null hypothesis that correlations are regime-independent. Using weekly stock returns for the S&P, the DAX and the FTSE over the period 1988,99, we find that international correlations significantly increased during turbulent periods. (J.E.L.: C53, G15). [source] Microstructure of microemulsion in MEEKCELECTROPHORESIS, Issue 4 2010Yuhua Cao Abstract The influences of the composition of microemulsion on the microstructure including dimensions and , potentials of microdroplets were measured in details. The average dynamic dimension of microdroplets was measured by dynamic laser light scattering, and , potential was determined to characterize average surface charge density of microdroplets. The experiment results showed that increase of the amount of surfactant resulted in decrease of microdroplet size but almost invariant , potential, which would enlarge migration time of the microdroplet in MEEKC. With increment of cosurfactant concentration, the microdroplet size had an increasing trend, whereas the , potential decreased. Thus, observed migration velocity of microdroplets increased, which made the separation window in MEEKC shortened. Neither dimension nor , potential of microdroplets changed by varying both the type and the amount of the oil phase. Adding organic solvent as modifier to microemulsion did not change the microdroplet size, but lowered , potential. The migration time of microdroplet still became larger, since EOF slowed down owing to organic solvent in capillary. So, besides increment of surfactant concentration, organic additive could also enlarge the separation window. Increase of cosurfactant concentration was beneficial for separation efficiency thanks to the looser structure of swollen microdroplet, and the peak sharpening might compensate for the resolution and peak capacity owing to a narrow separation window. Except the oil phase, tuning the composition of microemulsion would change the microstructure, eventually could be exploited to optimize the resolution and save analysis time in MEEKC. [source] Effect of organic carbon content, clay type, and aging on the oral bioavailability of hexachlorobenzene in rats,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2007Shakil A. Saghir Abstract Bioavailability of lipophilic chemicals is influenced by the physicochemical properties of soils/sediment such as particle size, pH, clay, and organic carbon content. The present study investigated the effects of sediment composition and aging on the oral bioavailability of hexachlorobenzene (HCB) in rats. Formulated sediments were prepared using various ratios of kaolinite and montmorillonite clay, sand, peat moss, and black carbon, spiked with 14C-HCB, and orally administered to rats prior to and after one year of aging in dark at 10°C. In the nonaged sediments there was a 21 to 45% reduction in the oral bioavailability of HCB when compared to the corn oil standard without any clear pattern of the impact of the sediment clay and/or organic carbon content. One year of aging resulted in statistically significant (p = 0.049) reduction in the oral bioavailability of HCB from the sediments compared to the corn oil standard and nonaged sediment indicating stronger interactions between HCB and sediment contents with aging. The mean reduction in oral bioavailability after one year of aging ranged from approximately 5 to 14% greater than that observed for nonaged sediments. The fecal elimination of the HCB-derived radioactivity from the one-year-aged sediments was much higher than the nonaged sediments, consistent with the lower absorption from the gastrointestinal tract due to lower desorption of HCB from the aged sediments. Increase in the fecal elimination and decrease in oral bioavailability of 14C-HCB was related to the increase in clay and black carbon. [source] Intracellular Calcium Increase in Epileptiform Activity: Modulation by Levetiracetam and LamotrigineEPILEPSIA, Issue 7 2004Antonio Pisani Summary:,Purpose: Alterations in neuronal calcium (Ca2+) homeostasis are believed to play an essential role in the generation and propagation of epileptiform events. Levetiracetam (LEV) and lamotrigine (LTG), novel antiepileptic drugs (AEDs), were tested on epileptiform events and the corresponding elevations in intracellular Ca2+ concentration ([Ca2+]i) recorded from rat neocortical slices. Methods: Electrophysiological recordings were performed from single pyramidal neurons from a slice preparation. Spontaneous epileptiform events consisting of long-lasting, repetitive paroxysmal depolarization shifts (PDSs) and interictal spike activity were induced by reducing the magnesium concentration from the solution and by adding bicuculline and 4-aminopyridine. Simultaneously, microfluorimetric measurements of [Ca2+]i were performed. Optical imaging with Ca2+ indicators revealed a close correlation between Ca2+ transients and epileptiform events. Results: Both LEV and LTG were able to reduce both amplitude and duration of PDSs, as well as the concomitant elevation in [Ca2+]i, in a dose-dependent fashion. Whole-cell patch-clamp recordings from isolated neocortical neurons revealed that LEV significantly reduced N-, and partially P/Q-type high-voltage-activated (HVA) Ca2+ currents, whereas sodium currents were unaffected. Interestingly, the inhibitory effects of LEV were mimicked and occluded by LTG or by a combination of ,-conotoxin GVIA and ,-agatoxin IVA, selective blockers of N- and P/Q-type HVA channels, respectively, suggesting a common site of action for these AEDs. Conclusions: These results demonstrate that large, transient elevations in neuronal [Ca2+]i correlate to epileptiform discharges. The antagonistic effects of LEV and LTG on [Ca2+]i overload might represent the basis for their anticonvulsant efficacy and could preserve neuronal viability. [source] Zonisamide Reduces the Increase in 8-Hydroxy-2,-Deoxyguanosine Levels Formed During Iron-Induced Epileptogenesis in the Brains of RatsEPILEPSIA, Issue 9 2000M. Komatsu Summary: Purpose: To examine the change of 8,-hydroxy-2,-deoxyguanosine (8-OHdG) levels, which are used as a marker for oxidative DNA damage, in iron-induced epileptogenic foci of the rat cerebrum. Method: Male Wistar rats were given a cortical injection of ferric chloride, and their 8-OHdG levels were determined over time. Additional animals were pretreated with the antiepileptic drug zonisamide (ZNS) before the ferric chloride injection, and their 8-OHdG levels were compared with the nonpretreated rats. Results: Fifteen minutes after ferric chloride solution injection, the level of 8-OHdG increased, reaching a maximum 30 minutes after injection. Sixty minutes after injection, the levels coincided with those of controls. ZNS, in concentrations of 50 and 100 mg/kg body weight, prevented the increase of 8-OHdG levels within the cerebrum 30 minutes after iron solution injection. Conclusions: These results indicate that the formation of iron-induced epileptogenic foci in rats is related to DNA-damage-induced reactive oxygen species and that the inhibition of 8-OHdG formation by ZNS after iron injection may be due to the drug's antioxidant activity. The data suggest that free radical species known to be formed during iron salts,induced focal epileptogenesis cause damage to isocortical DNA. Furthermore, ZNS appears to inhibit the focal injuring response to DNA that occurs following iron salts,induced acute epileptogenesis. [source] The noradrenaline plasma concentration and its gradient across the lungEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 8 2000Marenzi Background We investigated the lung contribution to circulating noradrenaline (NA) homeostasis. Evaluation of the transpulmonary NA gradient, related to the NA amount entering the lungs, is potentially important, mainly regarding clinical conditions, such as congestive heart failure (CHF), that are associated with excessive circulating NA. Materials and methods 15 moderate (group 1) and 15 severe (group 2) CHF patients, and 10 normal individuals had determination of NA transpulmonary gradient in the baseline and during rise (exercise, in normals and group 1) or fall (withdrawal from plasma by ultrafiltration, in group 2) of plasma NA. Results NA gradient (pg mL,1) at rest was 30 ± 3 in normals, 21 ± 6 in group 1 and 5 ± 8 in group 2. Increase of NA concentration in the mixed venous blood with exercise was paralleled by depression of the transpulmonary gradient. Pulmonary arteriovenous difference disappeared when NA entering the lungs averaged 1300 pg mL,1. In group 2, ultrafiltration lowered NA in the mixed venous blood from 1225 ± 213 to 718 ± 182, which caused transpulmonary gradient to increase from 5 ± 8 to 22 ± 9. Conclusions Transpulmonary gradient of NA diminishes when NA entering the lungs increases, and 1300 pg mL,1 in the pulmonary artery is, both in patients and normal subjects, the level at which gradient disappears; which likely reflects cessation of NA uptake or achievement of a balance between lung uptake and production. This may have physiological and pathological implications. [source] Effect of digoxin on circadian blood pressure values in patients with congestive heart failureEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2000Kirch Background The aim of the study was to investigate the effect of chronic digoxin treatment on circadian blood pressure profile in normotensive patients with mild congestive heart failure. Methods In a randomized double-blind, placebo-controlled cross-over protocol, 12 normotensive patients with mild congestive heart failure took digoxin or placebo for a total of 7 days. Automatic 24-h ambulatory blood pressure measurements were carried out at day 7, of either digoxin or placebo. Results Diastolic blood pressure significantly decreased and systolic blood pressure significantly increased during overnight sleep in the digoxin phase compared to placebo. Digoxin had no effect on either systolic or diastolic blood pressure during daytime. Heart rate decreased in the overnight sleeping phase but did not differ significantly between placebo and digoxin phase. Conclusions Digoxin significantly decreases diastolic blood pressure during overnight sleep in patients with congestive heart failure. This effect is likely to be caused by reduction of sympathetic activity or increase of parasympathetic activity. Increase of systolic blood pressure during sleep is probably caused by the positive inotropic effect of the drug. [source] CLINICAL STUDY: BRIEF REPORT: Serum levels of vascular endothelial growth factor A increase during alcohol withdrawalADDICTION BIOLOGY, Issue 3 2010Annemarie Heberlein ABSTRACT Vascular endothelial growth factor A (VEGF-A) is a key regulator of angiogenesis. This study investigated VEGF-A serum levels during alcohol withdrawal (days 1, 7 and 14, 76 male patients, 38 healthy controls). Patients showed significantly higher VEGF-A serum levels (t = 2.620, P = 0.010), which increased significantly during withdrawal (F = 4.484, P = 0.014, mean difference = ,36.835, P = 0.037). The increase of VEGF-A serum levels was significantly associated with initial breath alcohol concentration and the sumscore of the severity scale of alcohol dependence (SESA questionnaire, F = 5.252, P = 0.008). Increase of VEGF-A serum levels is closely associated to alcohol intoxication and severity of alcohol dependence. [source] Efficient Increase of DNA Cleavage Activity of a Diiron(III) Complex by a Conjugating Acridine GroupEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 34 2007Xiao-Qiang Chen Abstract A new diferric complex, Fe2Lb, in which a DNA intercalator (acridine) is linked to a precursor diferric complex (Fe2La), has been designed and synthesised as a hydrolytic cleaving agent of DNA. Compared with Fe2La (without the DNA intercalator) (La: 2,6-bis{[(2-hydroxybenzyl)(pyridin-2-yl)methylamino]methyl}-4-methylphenol), Fe2Lb [Lb: 5-(acridin-9-yl)- N -(3,5-bis{[(2-hydroxybenzyl)(pyridin-2-yl)methylamino]methyl}-4-hydroxybenzyl)pentanamide] leads to a 14-fold increase in the cleavage efficiency of plasmid DNA due to the binding interaction between DNA and the acridine moiety. The interaction has been demonstrated by UV/Vis absorption, CD spectroscopy, viscidity experiments and thermal denaturation studies. The hydrolytic mechanism is supported by evidence from T4 DNA ligase assay, reactive oxygen species (ROS) quenching and BNPP [bis(4-nitrophenyl) phosphate, a DNA model] cleavage experiments. The pH dependence of the BNPP cleavage by Fe2La in aqueous buffer media shows a bell-shaped pH,kobs profile with an optimum point around a pH of 7.0 which is in good agreement with the maximum point of the pH-dependent relative concentration curve of active species from the pH titration experiments. The determination of the initial rates at a pH of 7.36 as a function of substrate concentration reveals saturation kinetics with Michaelis,Menten-like behaviour and Fe2La shows a rate acceleration increase of 4.7,×,106 times in the hydrolysis of BNPP. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] PRECLINICAL STUDY: Effect of cannabinoids on platelet serotonin uptakeADDICTION BIOLOGY, Issue 2 2007Marie Velenovská ABSTRACT Serotonin is involved in many of the same processes affected by cannabinoids; therefore, we investigated in vitro and in vivo effects of these drugs on the function of serotonin transporter. The effect of ,9 -tetrahydrocannabinol (,9 -THC), endocannabinoid anandamide and synthetic cannabinoid receptor agonist WIN 55,212-2 on platelet serotonin uptake and membrane microviscosity was examined in 19 marijuana smokers and 20 controls. (1) Serotonin uptake was inhibited at higher doses of ,9 -THC (IC50 = 139 µmol/l), anandamide (IC50 = 201 µmol/l) or WIN 55,212-2 (IC50 = 17.4 µmol/l); the inhibition was found non-competitive. ,9 -THC, anandamide and WIN 55,212-2 produced different effects on the membrane microviscosity. (2) Maximal velocity of platelet serotonin uptake was significantly increased in a group of chronic marijuana smokers suffering impairment of cognitive functions when compared with controls. Opposite effect of marijuana smoking on the serotonin uptake efficiency was observed in males beside females. In summary, this study provides evidence that (1) Activity of serotonin transporter is acutely affected by cannabinoids at relatively high drug concentrations; this effect is indirect and can be partially accounted for the changes in the membrane microviscosity. (2) Increase of maximal velocity of the serotonin uptake could be understood as adaptation change in the serotonergic system induced by chronic cannabis use. A hypothesis was supported that lowered serotonin uptake may reflect a gender-related differences in effects of psychoactive cannabinoids. [source] Going Ultra: How We Can Increase the Length Scales Studied in Small-Angle Neutron Scattering,ADVANCED ENGINEERING MATERIALS, Issue 6 2009Melissa A. Sharp Abstract Small-angle neutron scattering (SANS) has over the years proved to be a popular technique to investigate a variety of problems in materials science, since the length scales probed by this technique (1,100,nm) are ideal for many systems. However, there are a number of problems where the length scale of interest is larger. In order to study such systems it is possible to combine SANS with ultra-small-angle neutron scattering (USANS). This allows the study of structures from a few nanometers up to 50,µm. Here it is shown how the combination of SANS and USANS has allowed for a wider range of problems within materials science and polymer science to be solved. [source] Increase in the fracture toughness and bond energy of clay by a root exudateEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2008B. Zhang Summary Root exudates help drive the formation of the rhizosphere by binding soil particles, but the underlying physical mechanisms have not been quantified. This was addressed by measuring the impact of a major component of root exudates, polygalacturonic acid (PGA), on the interparticle bond energy and fracture toughness of clay. Pure kaolinite was mixed with 0, 1.2, 2.4, 4.9 or 12.2 g PGA kg,1 to form test specimens. Half of the specimens were washed repeatedly to remove unbound PGA and evaluate the persistence of the effects, similar to weathering in natural soils. Fracture toughness, KIC, increased exponentially with added PGA, with washing increasing this trend. In unwashed specimens KIC ranged from 54.3 ± 2.5 kPa m,1/2 for 0 g PGA kg,1 to 86.9 ± 4.7 kPa m,1/2 for 12.2 g PGA kg,1. Washing increased KIC to 61.3 ± 1.2 kPa m,1/2 for 0 g PGA kg,1 and 132.1 ± 4.9 kPa m,1/2 for 12.2 g PGA kg,1. The apparent bond energy, ,, of the fracture surface increased from 5.9 ± 0.6 J m,2 for 0 g kg,1 to 12.0 ± 1.1 J m,2 for 12.2 g kg,1 PGA in the unwashed specimens. The washed specimens had , of 13.0 ± 1.9 J m,2 for 0 g kg,1 and 21.3 ± 2.6 J m,2 for 12.2 g PGA kg,1. Thus PGA, a major component of root exudates, has a large impact on the fracture toughness and bond energy of clay, and is likely to be a major determinant in the formation of the rhizosphere. This quantification of the thermodynamics of fracture will be useful for modelling rhizosphere formation and stability. [source] Understanding the partial discharge activity of conducting particles in GIS under DC voltages using the UHF techniqueEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 5 2010R. Sarathi Abstract The major cause of failure of DC-GIS is due to presence of foreign particles causing partial discharges in the insulation structure. The particle movement in gas insulated system (GIS) radiates electromagnetic waves and the bandwidth of the signal lies in the range 1,2,GHz. Increase in applied DC voltage/pressure has not altered the frequency content of the ultra high frequency (UHF) signal generated due to partial discharge formed by particle movement. The UHF sensor could recognize the breakdown of sulfur-hexa-fluoride (SF6) gas under DC and Lightning impulse voltages and the frequency content of the signal captured by the UHF sensor lies up to 500,MHz. Mounting UHF sensor in GIS could allow one to classify internal partial discharges from breakdown, at the time of testing/during operation. Copyright © 2009 John Wiley & Sons, Ltd. [source] Multiple P2 Receptors Contribute to a Transient Increase in Intracellular Ca2+ Concentration in Atp-Stimulated Rat Brown AdipocytesEXPERIMENTAL PHYSIOLOGY, Issue 6 2002Mariko Omatsu-Kanbe Extracellular ATP in micromolar concentrations evokes a transient elevation in intracellular free Ca2+ concentration ([Ca2+]i), which arises primarily from a release of Ca2+ from intracellular stores in rat brown adipocytes. We investigated the mechanisms underlying this transient nature of [Ca2+]i elevation during exposure to ATP by using fura-2 fluorescence measurements together with the P2 receptor antagonists pyridoxal-phosphate-6-azophenyl-2,,4,-disulfonic acid (PPADS) and suramin. Extracellular ATP (10 ,M) almost completely depressed the thapsigargin (100 nM)-evoked [Ca2+]i elevation mediated through store-operated Ca2+ entry. The inhibitory effect of ATP was antagonized by PPADS with IC50 of 0.7 ,M. In the presence of PPADS at concentrations of more than 5 ,M, the ATP-induced [Ca2+]i elevation became sustained during the entire duration of the agonist application, although the magnitude of the sustained [Ca2+]i elevation was reduced in a concentration-dependent manner by PPADS with an IC50 of 200 ,M. In contrast, the ATP-induced [Ca2+]i elevation was blocked by suramin in a concentration range similar to that required to antagonize the inhibitory effect of ATP on the store-operated pathway. These results suggest that the [Ca2+]i responses to extracellular ATP in rat brown adipocytes are mediated through the activation of at least two distinct P2 receptors exhibiting different sensitivities to PPADS but similar sensitivities to suramin. Extracellular ATP stimulates the PPADS-resistant P2 receptor to mobilize intracellular Ca2+ stores, which is probably followed by the activation of store-operated Ca2+ entry. Extracellular ATP, however, would inhibit this Ca2+ entry process through the stimulation of the PPADS-sensitive P2-receptor, which may underlie the transient nature of [Ca2+]i elevation in response to extracellular ATP. [source] Increase of calnexin gene dosage boosts the secretion of heterologous proteins by Hansenula polymorphaFEMS YEAST RESEARCH, Issue 7 2007Jens Klabunde Abstract The type I membrane protein calnexin is a conserved key component of the quality control mechanism in the endoplasmic reticulum. It functions as a molecular chaperone that monitors the folding state of nascent polypeptides entering the endoplasmic reticulum. Calnexin also behaves as a lectin, as its chaperoning activity involves binding of oligosaccharide moieties present on newly imported glycoproteins. We isolated the calnexin gene (HpCNE1) from the methylotrophic yeast Hansenula polymorpha, and used HpCNE1 expression plasmids for supertransformation of H. polymorpha strains secreting target proteins of biotechnological interest. The elevated dosage of HpCNE1 enhanced secretion of the four proteins tested: three glycoproteins and one unglycosylated product. Secretion of bacterial alginate epimerase AlgE1 was increased threefold on average, and secretion of both human interferon-, and fungal consensus phytase twofold. With phytase and AlgE1 this improvement was all the more remarkable, as the secretion level was already high in the original strains (g L,1 range). The same approach improved secretion of human serum albumin, which lacks N-linked glycans, about twofold. Glycosylation of the pro-MF,1 leader may account for the effect of calnexin in this case. Our results argue that cooverexpression of calnexin can serve as a generally applicable tool for enhancing the secretion of all types of heterologous protein by H. polymorpha. [source] Increase in photosynthetic efficiency as a strategy of planktonic organisms exploiting deep lake layersFRESHWATER BIOLOGY, Issue 2 2004Beatriz Modenutti Summary 1. The photosynthetic efficiencies of the mixotrophic ciliate Ophrydium naumanni and the autotrophic dinoflagellate Gymnodinium paradoxum were investigated using laboratory and field experiments in Lake Moreno Oeste (41°5,S and 71°33,W, 758 m a.s.l.), in the Nahuel Huapi System (North Patagonia, Argentina). 2. The effect of different underwater light intensities on net primary production (NPP) was assessed during one summer. Additionally, laboratory experiments were carried out to obtain photosynthesis-irradiance response curves for each species. 3. Ophrydium naumanni and G. paradoxum dominated the metalimnetic (30 m depth) deep chlorophyll maximum (DCM) in the lake. 4. Despite these deep higher abundances, the cell-specific production of both species was higher at 10 m than at 30 m (DCM) depth. In addition, at 5 m depth, NPP was reduced by PAR + UV-A radiation. 5. Both species exhibited a positive NPP at very low irradiance but the mixotrophic ciliate was more efficient in exploiting the DCM irradiance level both in situ and at comparable light intensities in laboratory experiments. Light acclimatised O. naumanni showed a higher NPP at lower irradiances and photoinhibition at medium and high irradiances. 6. Under the strong wind-driven turbulence commonly found in Patagonian lakes, organisms cannot select their position in the epilimnetic water column and will be dragged to potentially harmful UV radiation levels. Thus, metalimnetic DCM colonisation by these two species represents a tradeoff between higher survival and lower cell-specific NPP. [source] | |||||||||||||||||||||||||||||||||||||