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Terms modified by Ex Selected AbstractsExercise is the primary factor associated with Hsp70 induction in muscle of treadmill running ratsACTA PHYSIOLOGICA, Issue 4 2006E. G. Noble Abstract Aim:, The cytoprotective, inducible stress protein, Hsp70, increases in muscles of rodents subjected to strenuous treadmill running. Most treadmill running protocols employ negative reinforcement to encourage animals to exercise. As these stimuli may themselves activate stress responses, the present investigation was conducted to determine their contribution to the exercise-induced expression of Hsp70. Methods:, Twenty-one male Sprague,Dawley rats were randomly divided into three equal groups including an exercise group (EX), which ran on a treadmill at 30 m min,1 for 60 min; a stimulation group (STIM), which was not allowed to run, but was stimulated with compressed air and mild electric shock concurrently with their exercising cohort; and a control group (CON), which was housed in the treadmill room during the exercise period. Animals were killed 24 h post-experiment and hearts (H), soleii (SOL) and white gastrocnemii (WG) were harvested and analysed for Hsp70 content (mean% ± SEM of standard). Results:, Significant increases in Hsp70 (as a % of standard) were noted in H and WG (H = 77.4 ± 8.5; WG = 93.9 ± 18.4) of EX but not in STIM (H = 32.5 ± 4.6; WG = 32.0 ± 3.4) or CON (H = 20.5 ± 3.7; WG = 32.4 ± 7.4). In SOL, Hsp70 expression in EX (126.7 ± 6.2) was different from STIM (98.3 ± 10.9) only. This occurred, despite the fact that all groups were exposed to a stressful environment and exhibited elevated (P < 0.001) temperatures (EX ,41.2 ± 0.1 °C > STIM ,40.5 ± 0.2 °C > CON ,39.0 ± 0.1 °C) indicative of a general stress response. Conclusions:, These data suggest that exercise per se, rather than environmental conditions or noxious stimuli, are responsible for the induction of Hsp70 in rat muscle during treadmill running. [source] Complete basis set extrapolations of dispersion, exchange, and coupled-clusters contributions to the interaction energy: a helium dimer study,INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 12 2008gorzata Jeziorska Abstract Effectiveness of various extrapolation schemes in predicting complete basis set (CBS) values of interaction energies has been investigated for the helium dimer as a function of interatomic separation R. The investigations were performed separately for the leading dispersion and exchange contributions to the interaction energy and for the interaction energy computed using the coupled cluster method with single and double excitations (CCSD). For all these contributions, practically exact reference values were obtained from Gaussian-type geminal calculations. Sequences of orbital basis sets augmented with diffuse and bond functions or augmented with two sets of diffuse functions have been employed, with the cardinal numbers up to X = 7. The functional form EX = ECBS + A(X , k),, was applied for the extrapolations, where EX is the contribution to the interaction energy computed with a basis set of cardinal number X. The main conclusion of this work is that CBS extrapolations of an appropriate functional form generally improve the accuracy of the interaction energies at a very small additional computational cost (of the order of 10%) and should be recommended in calculations of interatomic and intermolecular potentials. The effectiveness of the extrapolations significantly depends, however, on the interatomic separation R and on the composition of the basis set. Basis sets with midbond functions, well known to provide at a given size much more accurate nonextrapolated results than bases lacking such functions, have been found to perform best also in extrapolations. The X,1 extrapolations of dispersion energies computed with midbond function turned out to be very efficient (except at large R), reducing the errors by an order of magnitude for small X and a factor of two for large X (where the errors of nonextrapolated results are already very small). If midbond functions are not used, the X,3 formula is most appropriate for the dispersion energies. For the exchange component of the interaction energy, the best results are obtained,in both types of basis sets,with the X,4 extrapolation, which leads (in both cases) to almost an order of magnitude reduction of the error. The X,3 and (X , 1),3 extrapolations work also well, but give smaller improvements. The correlation component of the CCSD interaction energy extrapolates best with , between 2 and 3 for bases with midbond functions and between 3 and 4 for bases without such functions. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [source] Oxidative stress during leukocyte absorption apheresisJOURNAL OF CLINICAL APHERESIS, Issue 2 2003Aki Hirayama Abstract Leukocyte absorption apheresis absorbs leukocytes to the apheresis columns involving leukocyte activation. This process is regarded as bioincompatible and avoided in hemodialysis or other extracorporeal circulation processes. Thus, leukocyte apheresis has a potential risk to exacerbate in vivo oxidative stress. We evaluated the changes in plasma oxidative stress during leukocyte apheresis. Patients diagnosed as ulcerative colitis (UC) and treated with leukocyte apheresis were studied. Adacolumn (celluloseacetate beads) or Cellsorba EX (polyethylenephtarate fiber) was used for the leukocyte absorption device. Oxidative stress was measured by thiobarbituric acid reactive substances (TBARS) and hydroxyl radical (,OH) scavenging activity. Plasma samples were collected from the pre- and post-column sampling port at the start, and from the pre-column sampling port at the end of the treatment. The ,OH signal intensities (OHRI) significantly increased during a column passage, indicating a loss of plasma ,OH scavenging activity. However, OHRI was reduced at the end, suggesting a recovery of radical scavenging activity during leukocyte apheresis. Significant decreases of OHRI and TBARS were only observed in the early phase of the therapeutic course. No differences of OHRI and TBARS levels were observed between the two columns. These results indicate that though the plasma antioxidant activity was diminished by a column passage, plasma antioxidant activity recovers during the procedure. This efficient antioxidative effect is limited to the early phase of the therapeutic course. J. Clin. Apheresis 18:61,66, 2003. © 2003 Wiley-Liss, Inc. [source] Long-term effects of calorie restriction on serum sex-hormone concentrations in menAGING CELL, Issue 2 2010Roberto Cangemi Summary Calorie restriction (CR) slows aging and consistently reduces circulating sex hormones in laboratory animals. However, nothing is known regarding the long-term effects of CR with adequate nutrition on serum sex-hormone concentration in lean healthy humans. In this study, we measured body composition, and serum total testosterone, total 17-,-estradiol, sex hormone,binding globulin (SHBG), and dehydroepiandrosterone sulfate (DHEA-S) concentrations in 24 men (mean age 51.5 ± 13 years), who had been practicing CR with adequate nutrition for an average of 7.4 ± 4.5 years, in 24 age- and body fat,matched endurance runners (EX), and 24 age-matched sedentary controls eating Western diets (WD). We found that both the CR and EX volunteers had significantly lower body fat than the WD volunteers (total body fat, 8.7 ± 4.2%; 10.5 ± 4.4%; 23.2 ± 6.1%, respectively; P = 0.0001). Serum total testosterone and the free androgen index were significantly lower, and SHBG was higher in the CR group than in the EX and WD groups (P , 0.001). Serum 17,-estradiol and the estradiol:SHBG ratio were both significantly lower in the CR and EX groups than in the WD group (P , 0.005). Serum DHEA-S concentrations were not different between the three groups. These findings demonstrate that, as in long-lived CR rodents, long-term severe CR reduces serum total and free testosterone and increases SHBG concentrations in humans, independently of adiposity. More studies are needed to understand the role of this CR-mediated reduction in sex hormones in modulating the pathogenesis of age-associated chronic diseases such as cancer and the aging process itself. [source] The effect of caloric restriction interventions on growth hormone secretion in nonobese men and womenAGING CELL, Issue 1 2010Leanne M. Redman Summary Lifespan in rodents is prolonged by caloric restriction (CR) and by mutations affecting the somatotropic axis. It is not known if CR can alter the age-associated decline in growth hormone (GH), insulin-like growth factor (IGF)-1 and GH secretion. To evaluate the effect of CR on GH secretory dynamics; forty-three young (36.8 ± 1.0 years), overweight (BMI 27.8 ± 0.7) men (n = 20) and women (n = 23) were randomized into four groups; control = 100% of energy requirements; CR = 25% caloric restriction; CR + EX = 12.5% CR + 12.5% increase in energy expenditure by structured exercise; LCD = low calorie diet until 15% weight reduction followed by weight maintenance. At baseline and after 6 months, body composition (DXA), abdominal visceral fat (CT) 11 h GH secretion (blood sampling every 10 min for 11 h; 21:00,08:00 hours) and deconvolution analysis were measured. After 6 months, weight (control: ,1 ± 1%, CR: ,10 ± 1%, CR + EX: ,10 ± 1%, LCD: ,14 ± 1%), fat mass (control: ,2 ± 3%, CR: ,24 ± 3%, CR + EX: ,25 ± 3%, LCD: ,31 ± 2%) and visceral fat (control: ,2 ± 4%, CR: ,28 ± 4%, CR + EX: ,27 ± 3%, LCD: ,36 ± 2%) were significantly (P < 0.001) reduced in the three intervention groups compared to control. Mean 11 h GH concentrations were not changed in CR or control but increased in CR + EX (P < 0.0001) and LCD (P < 0.0001) because of increased secretory burst mass (CR + EX: 34 ± 13%, LCD: 27 ± 22%, P < 0.05) and amplitude (CR + EX: 34 ± 14%, LCD: 30 ± 20%, P < 0.05) but not to changes in secretory burst frequency or GH half-life. Fasting ghrelin was significantly increased from baseline in all three intervention groups; however, total IGF-1 concentrations were increased only in CR + EX (10 ± 7%, P < 0.05) and LCD (19 ± 4%, P < 0.001). A 25% CR diet for 6 months does not change GH, GH secretion or IGF-1 in nonobese men and women. [source] Methodology for drawing up a Red List of threatened freshwater fish in FranceAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2002P. Keith Abstract 1.In 1995, the IUCN implemented new definitions to be used when drawing up red lists. However, in addition to being imprecise for fish species, these remain difficult to apply. 2.This paper describes a more exhaustive method under the IUCN (1995) definitions based on six quantitative and qualitative criteria where scientific data are given the greatest possible weight, as compared with ,expert opinion'. This dual system makes it possible both to allocate an IUCN category to each species, and to rank each species within a particular category according to given scores, so that priorities can be determined. 3.The new Red List for French Freshwater Fish drawn up with this method contains 27 species, or 54% of the French native fauna. Three species are extinct (EX), four are critically endangered (CR), two are endangered (EN), 14 are vulnerable (VU), and four are at lower risk (LR). 4.Based on sounder scientific grounds, this list modifies and replaces the one drawn up in 1992. In effect, it makes it easier to argue for the presence of one species in one category rather than in another. Copyright © 2002 John Wiley & Sons, Ltd. [source] A combination of soy isoflavone supplementation and exercise improves lipid profiles and protects antioxidant defense-systems against exercise-induced oxidative stress in ovariectomized ratsBIOFACTORS, Issue 4 2007Hea Young Oh Abstract Menopause is often accompanied with weight gain, metabolic lipid abnormalities, and oxidative stress. In this study, we investigated the combined effects of exercise and soy isoflavone supplemention on the lipid profiles and antioxidant capacities of ovariectomized rats. Twenty-five female Sprague-Dawley rats were divided into 5 groups: sham-operated, ovariectomized (OVX), OVX with exercise (OVX + EX), OVX with soy isoflavone supplementation (OVX + ISO), and OVX with both soy isoflavones and exercise (OVX + ISO + EX). After 12 weeks of intervention, antioxidant status was evaluated in collected blood samples by the ferric reducing ability of plasma (FRAP), glutathione (GSH) content, and sodium oxide dismutase (SOD) activity. DNA damage in the lymphocytes was determined using alkaline single-cell gel electrophoresis (the Comet assay). Although there were no significant differences in weight gain and food intake, weight gain was lower in OVX + EX, OVX + ISO, and OVX + ISO + EX than in OVX. OVX + EX, OVX + ISO, and OVX + ISO + EX showed a significant decrease in total cholesterol, triglycerides, and LDL-cholesterol compared to OVX. The soy isoflavone supplemented group had significantly increased FRAP values and GSH contents in contrast to no changes in the exercised group, whereas exercise markedly increased SOD activity and H2O2 -induced DNA tail length and tail moment. Exercise with soy isoflavone supplementation significantly increased FRAP values and had no difference on SOD activity, including DNA damage. These results demonstrate that a combined treatment of moderate exercise and soy isoflavone supplementation could exert a beneficial effect on weight control and lipid profiles, and offer protection from exercise-induced oxidative stress in postmenopausal women. [source] Carotid artery revascularization in high surgical risk patients with the NexStent and the Filterwire EX/EZCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 20081-Year results in the CABERNET trial Abstract Objective: The multicenter, single-arm CABERNET trial evaluated outcomes in high-surgical-risk patients with carotid artery stenosis treated with the NexStent® plus FilterWire EX®/EZÔ Emboli Protection System. Background: For patients at high surgical risk, carotid artery stenting (CAS) offers a less invasive alternative to carotid endarterectomy (CEA). Methods: The trial enrolled 454 high-surgical-risk patients with carotid stenosis by angiography ,50% for symptomatic patients and ,60% for asymptomatic patients. The comparator primary endpoint was the 1-year major adverse event (MAE, defined as any death, stroke, or myocardial infarction [MI]) rate. It was compared with a proportionally weighted objective performance criterion (OPC) of 12.1% representative of published CEA results in similar patients plus a prespecified noninferiority margin (delta) of 4%. A second primary endpoint was the composite rate of 30-day MAE plus late (31,365 days) ipsilateral stroke. Results: Symptoms of carotid stenosis were present in 24.2% of patients; 36.6% of patients were considered high-surgical-risk due to comorbid risk factors and 63.4% due to anatomic risk factors. The rate of 30-day MAE plus late ipsilateral stroke was 4.7% (20/438). The comparator primary endpoint of 1-year MAE was 11.6% (51/438) and was noninferior to the OPC of 12.1% (95% upper confidence interval of 14.5% versus OPC plus delta of 16.1%, P = 0.005). Late ipsilateral stroke was 0.7% and target vessel revascularization at 1 year was 2.4%. Conclusions: The CABERNET trial demonstrates that CAS with NexStent and FilterWire is noninferior to (equivalent or better than) traditional CEA at 1 year in high-surgical-risk patients based on historical controls. © 2008 Wiley-Liss, Inc. [source] A new optimal foraging model predicts habitat use by drift-feeding stream minnowsECOLOGY OF FRESHWATER FISH, Issue 1 2002G. D. Grossman Abstract , There is substantial need for models that accurately predict habitat selection by fishes for purposes ranging from the elaboration of ecological theory to the preservation of biodiversity. We have developed a new and highly tractable optimal foraging model for drift-feeding fishes that is based on the profitability of occupying varying focal-point velocities in a stream. The basic model can be written as: Ix = (Ex * Px) = {(D * A * V) * [1/(1 + e(b + cV))]} , Sx, where: (1) Ix is the net energy intake at velocity x; (2) E is prey encounter rate; (3) P is prey capture success rate which can be modelled as 1/(1 + e(b + cV)) where b and c are fitting constants from the prey capture success curve; (4) D is the energy content of prey (J/m3) in the drift; (5) A is the visual reactive area of the fish; (6) V is velocity (cm/s); and (7) S is the cost of maintaining position (J/s). Given that D, A and S can be considered constant over the range of velocities occupied by these fishes, the model reduces to e(b + cV) = 1/(cV , 1) which we solved iteratively to yield an optimal focal-point velocity for species in each sample. We tested the model by comparing its predictions to the mean focal-point velocities (i.e. microhabitats) occupied by four species of drift-feeding minnows in two sites in a stream in North Carolina, USA. The model successfully predicted focal-point velocities occupied by these species (11 out of 14 cases) in three seasonal samples collected over 2 years at two sites. The unsuccessful predictions still were within 2 cm/s of the 95% confidence intervals of mean velocities occupied by fishes, whereas the overall mean deviation between optimal velocities and mean fish velocities was small (range = 0.9 and 3.3 cm/s for the warpaint shiner and the Tennessee shiner, respectively). Available focal-point velocities ranged from 0,76 to 0,128 cm/s depending on site and season. Our findings represent one of the more rigorous field tests of an optimal foraging/habitat selection model for aquatic organisms because they encompass multiple species and years, and for one species, multiple sites. Because of the ease of parameterization of our model, it should be readily testable in a range of lotic habitats. If validated in other systems, the model should provide critical habitat information that will aid in the management of riverine systems and improve the performance of a variety of currently used management models (e.g. instream flow incremental methodology (IFIM) and total maximum daily load calculations (TMDL)). Resumen 1. Existe una grave necesidad de modelos que predigan con precisión la selección de hábitat por parte de los peces con fines que van del desarrollo de la teoría ecológica a la conservación de la biodiversidad. Nosotros hemos desarrollado un modelo nuevo y de fácil manejo de alimentación óptima para peces que se alimentan de la deriva que se fundamenta en los diferentes beneficios energéticos derivados de ocupar velocidades focales distintas en un río. 2. El modelo básico puede formularse como: Ix = (Ex * Px) = {(D * A * V) * [1/(1 + e(b + cV))]} , Sx, donde: (1) Ix es el energía neta obtenida a la velocidad, x; (2) V es la velocidad (cm/s); (3) A es el area visual de reacción del pez; (4) D es la energía contenida en las presas (J/m3) en la deriva; (5) E es la tasa de encuentro de presas; (6) P es la probabilidad de captura de la presa, que puede representarse como 1/(1 + e(b + cV)) donde b y c son constantes; y (7) S es el coste de nadar para mantener la posición en la corriente (J/s). Puesto que D, A y S pueden considerarse constantes en el rango de velocidades que ocupan estos peces, el modelo se reduce a e(b + cV) = 1/(cV , 1) que resolvimos iterativamente para obtener una velocidad focal óptima para cada especie en cada muestreo. 3. Probamos el modelo comparando su predicciones con la velocidades focales medias (i.e. microhabitats) ocupadas por cuatro especies de ciprínidos que se alimentan de la deriva en un río de Carolina del Norte. El modelo predijo con éxito las velocidades focales ocupadas por estas especies (11/14 casos) en tres muestreos estacionales llevados a cabo a lo largo de dos años en dos estaciones. Incluso las predicciones fallidas se diferenciaron en menos de 2 cm/s del límite de confianza al 95% CIs de las velocidades medias ocupadas, y la diferencia media entre predicciones y observaciones fue pequeña (rango = 0.9 cm/s warpaint shiner, a 3.3-cm/s Tennessee shiner). El rango de las velocidades focales medias disponibles fue de 0,76 cm/s a 0,128 cm/s dependiendo de la localidad y estación del año. 4. Nuestros resultados son una de las pruebas de campo más rigurosas de un modelo de alimentación óptima/selección de hábitat para organismos acuáticos puesto que incluyen diversas especies, años y, para una de las especies, localidades. La facilidad de la estima de los parámetros del modelo hace que sea fácil probarlo en diversos hábitats lóticos. Si es validado en ellos, el modelo debería proporcionar información valiosa que ayudará a la gestión de los sistemas fluviales y mejorará los resultados obtenidos a través de varios modelos usados actualmente para la gestión (p.e. IFIM y cálculos TMDL). [source] Influence of oocyte collection technique on initial chromatin configuration, meiotic competence, and male pronucleus formation after intracytoplasmic sperm injection (ICSI) of equine oocytes,MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 1 2001Maria Elena Dell'Aquila Abstract There is a great variability in the success of horse oocyte maturation and fertilization among laboratories. This study was conducted to determine if the meiotic and developmental competence of horse oocytes could be dependent on the method of oocyte collection, i.e., aspiration of follicular fluid with a vacuum apparatus, or opening follicles and scraping the granulosa layer. Horse oocytes were recovered from abattoir ovaries by aspiration or scraping and classified as having compact (Cp), expanded (Ex), or partial (P) cumuli. In Experiment 1 (Part A in May and Part B in October), oocytes were fixed immediately after collection to assess whether the collection method influenced the initial chromatin configuration of oocytes. In Experiment 2, in vitro maturation rates of oocytes recovered by aspiration or scraping were compared. In Experiment 3, oocytes were matured in vitro and submitted to intracytoplasmic sperm injection (ICSI). Initial chromatin configuration differed according to collection method in that there was a significantly higher prevalence of diffuse chromatin within the germinal vesicle in oocytes recovered by scraping than in oocytes recovered by aspiration (29/87, 33% and 28/166, 17%, respectively; P,<,0.01). Maturation of oocytes to metaphase II did not significantly differ between scraped and aspirated oocytes (56/101, 55.4 % vs. 65/106, 61.4%, respectively). The overall pronucleus formation rate after ICSI of oocytes recovered by scraping was not significantly different than that of oocytes recovered by aspiration (50/99, 52.6% vs. 50/85, 68.5 %, respectively); however, the rate of abnormal fertilization was significantly higher for oocytes collected by aspiration (14/73, 19% vs. 6/94, 6%, respectively; P,<0.05). These results demonstrate that the collection method affects the population of recovered oocytes and may contribute to differences in results observed among laboratories working with horse oocytes. Mol. Reprod. Dev. 60: 79,88, 2001. © 2001 Wiley-Liss, Inc. [source] Phenotypic and functional characterization of mature dendritic cells from pediatric cancer patientsPEDIATRIC BLOOD & CANCER, Issue 7 2007Joannes F.M. Jacobs MD Abstract Background Dendritic cells (DCs) are the most potent antigen-presenting cells of the immune system. Clinical trials have demonstrated that mature DCs loaded with tumor-associated antigens can induce tumor-specific immune responses. Theoretically, pediatric patients are excellent candidates for immunotherapy since their immune system is more potent compared to adults. We studied whether sufficient amounts of mature monocyte-derived DCs can be cultured from peripheral blood of pediatric cancer patients. Procedure DCs from 15 pediatric patients with an untreated primary tumor were cultured from monocytes and matured with clinical grade cytokines. Phenotype and function were tested with flow cytometry, mixed lymphocyte reaction (MLR), and an in vitro migration assay. DCs of children with a solid tumor were compared with monocyte-derived DCs from age-related non-malignant controls. Results Ex vivo-generated monocyte-derived DCs from pediatric patients can be generated in numbers sufficient for DC vaccination trials. Upon cytokine stimulation the DCs highly upregulate the expression of the maturation markers CD80, CD83, and CD86. The mature DCs are six times more potent in inducing T cell proliferation compared to immature DCs. Furthermore, mature DCs, but not immature DCs, express the chemokine receptor CCR7 and have the capacity to migrate in vitro. Conclusions These data indicate that mature DCs can be generated ex vivo to further optimize DC-vaccination trials in pediatric cancer patients. Pediatr Blood Cancer 2007;49:924,927. © 2007 Wiley-Liss, Inc. [source] Electrophoresis on a microfluidic chip for analysis of fluorescence-labeled human rhinovirusELECTROPHORESIS, Issue 24 2007Viliam Kolivo Abstract We report the analysis of human rhinovirus serotype 2 (HRV2) on a commercially available lab-on-a-chip instrument. Due to lack of sufficient native fluorescence, the proteinaceous capsid of HRV2 was labeled with Cy5 for detection by the red laser (,ex 630,nm) implemented in the instrument. On the microdevice, electrophoresis of the labeled virus was possible in a BGE without stabilizing detergents, which is in contrast to conventional CE; moreover, analysis times were drastically shortened to the few 10,s range. Resolution of the sample constituents (virions, a contaminant present in all virus preparations, and excess dye) was improved upon adaptation of the separation conditions, mainly by adjusting the SDS concentration of the BGE. Purity of fractions from size-exclusion chromatography after labeling of virus was assessed, and affinity complex formation of the labeled virus with various recombinant very-low-density lipoprotein receptor derivatives differing in the number of concatenated V3 ligand binding repeats was monitored. Virus analysis on microchip devices is of particular interest for experiments with infectious material because of easy containment and disposal of samples. Thus, the employment of microchip devices in routine analysis of viruses appears to be exceptionally attractive. [source] Determination of tryptamine derivatives in illicit synthetic drugs by capillary electrophoresis and ultraviolet laser-induced fluorescence detectionELECTROPHORESIS, Issue 12 2005Carolin Huhn Abstract A method based on separation by capillary electrophoresis combined with UV-laser-induced fluorescence detection (,ex,=,266,nm) was developed for the determination of nine tryptamine derivatives of forensic interest and potential matrix constituents. The composition of the separation electrolyte was optimized with respect to the resolution of solutes of interest and to the sensitivity of fluorescence detection. Native ,-cyclodextrin was employed as a complex forming modifier of the electrophoretic separation and fluorescence-enhancing agent. With the help of a stacking procedure, limits of detection of 0.1,6,µg/L for all analytes were obtained. The repeatability for the peak area (at a concentration of the analyte about 100 times the LOD) was less than 2.3%,RSD. A second HPLC method was developed, and its analytical parameters were evaluated for an estimation of the accuracy of the CE-LIF method and for method comparison. The results of the determination of tryptamine derivatives in the samples of forensic interest obtained with the two independent methods are in good agreement. [source] d -Alanyl ester depletion of teichoic acids in Lactobacillus reuteri 100-23 results in impaired colonization of the mouse gastrointestinal tractENVIRONMENTAL MICROBIOLOGY, Issue 7 2007Jens Walter Summary The dlt operon of Gram-positive bacteria encodes proteins required for the incorporation of d -alanine esters into cell wall-associated teichoic acids (TA). d -Alanylation of TA has been shown to be important for acid tolerance, resistance to antimicrobial peptides, adhesion, biofilm formation, and virulence of a variety of pathogenic organisms. The aim of this study was to determine the importance of d -alanylation for colonization of the gastrointestinal tract by Lactobacillus reuteri 100-23. Insertional inactivation of the dltA gene resulted in complete depletion of d -alanine substitution of lipoteichoic acids. The dlt mutant had similar growth characteristics as the wild type under standard in vitro conditions, but formed lower population sizes in the gastrointestinal tract of ex- Lactobacillus -free mice, and was almost eliminated from the habitat in competition experiments with the parental strain. In contrast to the wild type, the dlt mutant was unable to form a biofilm on the forestomach epithelium during gut colonization. Transmission electron microscope observations showed evidence of cell wall damage of mutant bacteria present in the forestomach. The dlt mutant had impaired growth under acidic culture conditions and increased susceptibility to the cationic peptide nisin relative to the wild type. Ex vivo adherence of the dlt mutant to the forestomach epithelium was not impaired. This study showed that d -alanylation is an important cell function of L. reuteri that seems to protect this commensal organism against the hostile conditions prevailing in the murine forestomach. [source] Breaking Infinite CuI Carboxylate Helix Held by Cuprophilicity into Discrete Cun Fragments (n = 6, 4, 2)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2008Yulia Sevryugina Abstract A new copper(I) carboxylate complex with 3,5-bis(trifluoromethyl)benzoate ligands, [Cu(O2C(3,5-CF3)2C6H3)] (1), has been prepared in high yield and fully characterized. An X-ray diffraction study revealed a remarkable infinite double-helical chain motif held together by cuprophilic interactions ranging from 2.69 to 3.14 Å. Both left- and right-handed helices are present in the unit cell of the centrosymmetric structure of 1 thus making the crystalline compound racemic. Complex 1 shows bright emission at ca. 594 nm upon UV/Vis radiation in the solid state (,ex = 350 nm). The Cu···Cu contacts in 1 are easily broken in the gas phase to afford copper clusters of ascertained nuclearity upon sublimation with various polyaromatic hydrocarbons. Several polyarenes such as fluoranthene (C16H10), pyrene (C16H10), and coronene (C24H12) were selected to cover a broad temperature range from 130 to 220 °C for the gas-phase co-deposition reactions. As a result of the successive temperature increase, cleavage of the infinite copper(I) chain into [Cun(O2C(3,5-CF3)2C6H3)n] fragments of decreasing nuclearity, n = 6, 4, and 2, has been achieved. The isolation of these units represents the first instance where various polynuclear copper(I) complexes are prepared and structurally characterized for the same carboxylate ligand.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Synthesis of New Phenanthroline-Based Heteroditopic Ligands , Highly Efficient and Selective Fluorescence Sensors for Copper(II) IonsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 21 2006Peter Comba Abstract The heteroditopic phenanthroline derivatives 5,6-bis(2-pyridylcarboxamido)-1,10-phenanthroline (H2L1) and 5,6-bis[(4-methoxy-2-pyridyl)carboxamido]-1,10-phenanthroline (H2L2) have been prepared and characterized, together with their luminescent ruthenium(II) complexes [Ru(bpy)2(H2L1,2)](PF6)2 and [Ru(H2L1)3](PF6)2 and the corresponding iron(II) complex [Fe(H2L1)3](PF6)2. In these complexes, the metal ion is coordinated by the bidentate phen site of H2L. The luminescence of the ruthenium complexes (,ex = 450 nm, ,em ca. 620 nm) is completely quenched by Cu2+ ions in the micromolar concentration range and, to a lesser extent, by other metal ions. At pH 5, the response of the luminescent sensors is highly Cu2+ -selective. Heterodinuclear complexes [Ru(bpy)2(LM)](PF6)2, [Ru(LM)3](PF6)2, and [Fe(LM)3](PF6)2 have been isolated for M = Cu2+, Ni2+, Co2+, and Pd2+. It is suggested that M is coordinated to the tetradentate N4 site of L by two deprotonated amide N atoms and two pyridyl groups. This coordination type is confirmed by the EPR spectrum of the compound [RuII(bpy)2(L1CuII)](PF6)2.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Effect of cortical spreading depression on synaptic transmission of rat hippocampal tissuesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2006Brigitta Wernsmann Abstract Cortical spreading depression (CSD) is believed to be a putative neuronal mechanism underlying migraine aura and subsequent pain. In vitro and ex vivo/in vitro brain slice techniques were used to investigate CSD effects on the field excitatory postsynaptic potentials (fEPSP) and tetanus-induced long-term potentiation (LTP) in combined rat hippocampus,cortex slices. Induction of CSD in combined hippocampus,cortex slices in which DC negative deflections did not propagate from neocortex to hippocampus significantly augmented fEPSP amplitude and LTP in the hippocampus. Propagation of CSD to the hippocampus resulted in a transient suppression followed by reinstatement of fEPSP with amplitude of pre-CSD levels. LTP was inhibited when DC potential shifts were recorded in the hippocampus. Furthermore, CSD was induced in anaesthetized rats and, thereafter, hippocampal tissues were examined in vitro. LTP was significantly enhanced in hippocampal slices obtained from ipsilateral site to the hemisphere in which CSD was evoked. The results indicate the disturbances of hippocampal synaptic transmission triggered by propagation of CSD. This perturbation of hippocampal synaptic transmission induced by CSD may relate to some symptoms occurring during migraine attacks, such as amnesia and hyperactivity. [source] Generic disposition of Vicatia bipinnata in Melanosciadium and a new species (Umbelliferae)FEDDES REPERTORIUM, Issue 7-8 2006M. G. Pimenov Professor Dr. Taxonomically critical Chinese species Vicatia bipinnata, treated early also in the genus Sino-dielsia, found to be morphologically similar to Melanosciadium H.Boissieu, a previously monotypic genus, also endemic to China. A new combination in Melanosciadium [M. bipinnatum (Shan RenHwa & Pu FaTing ex Shan Ren-Hwa et al.) Pimenov & Kljuykov] has been proposed. A new species, Melanosciadium genuflexumPimenov & Kljuykov, closely related to M. bipinnatum has been described. A key to determination of three species of Melanosciadium has been compiled. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Verschiebung von Vicatia bipinnata in die Gattung Melanosciadium und eine neue Art (Umbelliferae) Die taxonomisch kritische chinesische Art Vicatia bipinnata, früher auch zur Gattung Sinodielsia gestellt, erwies sich als morphologisch ähnlich mit dem ebenfalls in China endemischen Melanosciadium H.Boissieu, eine ursprünglich monotypische Gattung. Es wird die Neukombination Melanosciadium bipinnatum (Shan RenHwa & Pu FaTing ex Sha RenHwa et al.) Pimenov & Kljuykov, comb. nov. vorgeschlagen. Die mit M. bipinnatum nahe verwandte Art M. genuflexumPimenov & Kljuykov sp. nova wird neu beschrieben. Ein Bestimmungsschlüssel für die drei Arten von Melanosciadium wird vorgelegt. [source] What is Sium frigidumHand.-Mazz. (Umbelliferae)?FEDDES REPERTORIUM, Issue 5-6 2003M. G. Pimenov Professor Dr. A rare and enigmatic Chinese species, known as Apium ventricosumH. Boissieu and Sium frigidumHand.-Mazz. (the latter name is only used in current floristic literature), has been shown to be closer related to SinocarumH. Wolff ex Shan RenHwa & PuFaTing. This affinity, indicated recently by ITS sequence investigation, was confirmed by morphological analysis. Attribution of the species to Apium, Sium, or Chamaesium, was not confirmed by molecular and morphological data either. A new combination, Sinocarum ventricosum (H. Boissieu) Pimenov & Kljuykov, has been proposed. The isolated position of S. ventricosum within the genus Sinocarum is emphazised by separation of a new monotypic section, Sinocarum sect. ApiopsisPimenov & Kljuykov. Was ist Sium frigidumHand.-Mazz. (Umbelliferae)? Eine seltene und rätselhafte chinesische Art, bekannt als Apium ventricosumH. Boissieu und Sium frigidumHand.-Mazz. (letzterer Name wird in der aktuellen floristischen Literatur allein benutzt), scheint näher verwandt zu sein mit SinocarumH. Wolff ex Shan RenHwa & Pu FaTing. Diese neuerlich durch IST-Sequenzanalyse festgestellte Affinität wurde durch molekulare und morphologische Daten bestätigt. Der Einschluss der Art in die Gattungen Apium, Sium oder Chamaesium konnte nicht durch molekulare und morphologische Merkmale bestätigt werden. Es wird eine Neukombination: Sinocarum ventricosum (H. Boissieu) Pimenov & Kljuykov vorgeschlagen. Die isolierte Stellung von S. ventricosum innerhalb der Gattung Sinocarum wird durch die Aufstellung einer monotypischen Sektion, Sinocarum sect. ApiopsisPimenov & Kljuykov unterstrichen. [source] Encapsulation and release of a fluorescent probe, khusimyl dansylate, obtained from vetiver oil by complex coacervationFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2008A. S. Prata Abstract The essential oil of vetiver [Vetiveria zizanoides (L.) Nash ex. Small] is widely used in the perfume industry, owing to its pleasant, long-lasting, woody aroma. If this substance can be encapsulated in microparticles so that its release can be controlled, the effective duration of its properties should be extended for a much longer period of time. The present study was thus designed to investigate the encapsulation of this vetiver essential oil in microparticles. Since the detection of the effective release of such a complex mixture from these microparticles into the receiving medium can be problematic, an identifiable probe can be released with it to facilitate evaluation of the progression of the release process. Zizanoic acid is one of the compounds found in vetiver oil which depreciates its sensorial quality. This acid was thus extracted and reduced to the corresponding alcohol, khusimol, which was combined with dansyl chloride to form a fluorescent ester, khusimyl dansylate (KD). The vetiver oil and the fluorescent probe were then encapsulated (100:1) in microparticles produced by the complex coacervation of gum Arabic and gelatin. The microparticles showed spherical shape, multinuclear distribution of the core material and high encapsulation efficiency (95%). Two versions of these microparticles, moist and freeze-dried ones, were tested for the release of the KD into an ethanol medium. The moist particles released the whole KD after 5 h, although only 80% of the fluorescent probe was released with the freeze-dried microparticles at that time, probably due to the constriction caused by freeze-drying. The release of the components of vetiver oil, under the same experimental conditions, was followed, in parallel, by gas chromatography and the results obtained were compared and discussed. Copyright © 2007 John Wiley & Sons, Ltd. [source] Thermogenesis and respiration of inflorescences of the dead horse arum Helicodiceros muscivorus, a pseudo-thermoregulatory aroid associated with fly pollinationFUNCTIONAL ECOLOGY, Issue 6 2003R. S. Seymour Summary 1In central Corsica, Helicodiceros muscivorus (Schott ex. K. Koch) produces a protogynous inflorescence that resembles the anal area of a dead mammal and produces a foetid scent during the few hours after sunrise. Flies enter the floral chamber, pollinate the female florets and become trapped until the next morning, when pollen is shed from the male florets and the flies are released. 2The exposed appendix exhibits a strong, unimodal episode of thermogenesis associated with scent production, reaching a maximum of 30 °C at 15 °C ambient temperature. The male florets in the floral chamber are highly thermogenic throughout the second night and generally maintain stable floret temperatures of about 24 °C at ambient temperatures down to 13 °C. 3Maximum respiration rates of the appendix (0·45 µmol CO2 s,1 g,1) and the male florets (0·82 µmol s,1 g,1) may be the highest recorded for plant tissue. 4Thermogenesis of the appendix does not depend on ambient temperature, but that of the male florets increases with decreasing ambient temperature in most cases. However, the pattern of heat production by the males appears related more to time than to ambient temperature, hence the term ,pseudo-thermoregulation'. 5The behaviour and thoracic temperatures of flies emerging from captivity suggests that male floral warming does not enhance their activity. [source] Analysis of Improved Efficiency of InGaN Light-Emitting Diode With Bottom Photonic Crystal Fabricated by Anodized Aluminum OxidxeADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Sang-Wan Ryu Abstract The improved performance of a bottom photonic crystal (PC) light-emitting diode (LED) is analyzed based on internal quantum efficiency (,int) and light-extraction efficiency (,ex). The bottom PC is fabricated by anodized aluminum oxide nanopatterns and InGaN quantum wells (QWs) are grown over it. Transmission electron microscopy images reveal that threading dislocations are blocked at the nanometer-sized air holes, resulting in improved optical emission efficiency of the QWs. From temperature-dependent photoluminescence measurements, the enhancement of ,int is estimated to be 12%. Moreover, the enhancement of ,ex is simulated to be 7% by the finite-difference time-domain method. The fabricated bottom PC LED shows a 23% higher optical power than a reference, which is close to the summation of enhancements in ,int and ,ex. Therefore, the bottom PC improves LED performance through higher optical quality of QWs as well as increased light extraction. [source] Globalization and cultural mediation: the construction of Arabia in LondonGLOBAL NETWORKS, Issue 4 2002Christa Salamandra The Arab Gulf's relationship to London epitomizes the processes of globalization i.e. flows of people, images, ideas and wealth beyond national borders. The rise of oil wealth in the mid,1970s financed the growth of London as a centre of Gulf Cooperation Council,funded Arab cultural production. The British capital's populations of ex,servicemen, former diplomats and Middle Eastern immigrants serve as ,third culture' mediators. Often well educated, well heeled and well connected, these intermediaries possess the social position and cultural know,how to play a central role in the construction and marketing of Gulf Arab local culture and heritage. Romantic notions of Gulf Arab cultural particularism feature prominently in mediators' products and activities. In the case of Arab London's mediation industries, globalization results not in cultural homogenization, but rather in the (re)production and commodification of reified notions of cultural difference. [source] Sensitized Lanthanide-Ion Luminescence with Aryl-Substituted N -(2-Nitrophenyl)acetamide-Derived ChromophoresHELVETICA CHIMICA ACTA, Issue 11 2009Michael Andrews Abstract The syntheses of the two tetraazamacrocyclic ligands L1 and L2 bearing a [(methoxy-2-nitrophenyl)amino]carbonyl chromophore, i.e., an N -(methoxy-2-nitrophenyl)acetamide moiety, together with their corresponding lanthanide-ion complexes are described. A combined spectroscopic (UV/VIS, 1H-NMR), structural (X-ray), and theoretical (DFT) investigation revealed that the absorption properties of the chromophores were dictated by the extent of electronic delocalisation, which in turn was determined by the position of the MeO substituent at the aromatic ring. X-Ray crystallographic studies showed that when attached to the macrocycle, both isomeric forms of the N -(methoxy-2-nitrophenyl)acetamide unit can participate in coordination, via the CO, to an encapsulated potassium cation. Luminescence measurements confirmed that such a binding mode also exists in solution for the corresponding lanthanide complexes (q ca. ,1), with the para -MeO derivative allowing longer wavelength sensitization (,ex 330,nm). [source] Premenopausal Smoking and Bone Density in 2015 Perimenopausal WomenJOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2000Dr. A. P. Hermann Abstract The importance of cigarette smoking in relation to bone mass remains uncertain, especially in younger women. In a recent meta-analysis including 10 studies in premenopausal women no effect was seen in this age group. We used baseline data from a large national cohort study (Danish Osteoporosis Prevention Study [DOPS]) to study the cumulated effect of pre- and perimenopausal smoking on bone mineral density (BMD) measured shortly after the cessation of cyclic bleedings. Baseline observations on 2015 recently menopausal women were available. Eight hundred thirty-two women were current smokers and 285 were exsmokers. Significant negative associations of cigarette smoking coded as current, ex-, or never smoking were seen on bone mass in the lumbar spine (P = 0.012), femoral neck (P < 0.001), and total body (P < 0.001). Quantitatively, the differences between current smokers and never smokers were limited to 1.6, 2.9, and 1.9%, respectively. A statistical interaction was found between smoking and fat mass, indicating that women in the highest tertile of fat mass were unaffected by cigarette smoking. Serum vitamin D levels and osteocalcin were inversely related to the number of cigarettes smoked per day (r = 0.11 and P < 0.001; r = 0.17 and P = 0.04), respectively. Bone alkaline phosphatase (BALP) and urinary hydroxyproline (U-OHP) were unaffected by current smoking. The average cumulated effect of premenopausal smoking on bone is small but biologically significant. Reduced body mass in smokers explains part of the negative effect on the skeleton and a complex interaction between smoking and fat mass on the skeleton is indicated. Serum levels of 25-hydroxyvitamin D (25-OHD) and osteocalcin are lower in smokers, which may effect rate of bone loss. [source] The Multivariate Analysis Biplot as tool for conflict analysis in MCDAJOURNAL OF MULTI CRITERIA DECISION ANALYSIS, Issue 5 2001Fabio B. Losa Abstract In this paper, the use of multivariate statistical analysis techniques to aid in conflict analysis in a multi-actor group is demonstrated. In particular, the covariance biplot technique is focused on and the resulting graphical output, called the conflict diagram, is interpreted in terms of relationships between actors, profiles of alternatives under consideration, and the interactions between actors and alternatives in terms of the conflict and its possible resolutions (consensus, coalition, etc.). The conflict analysis is divided into two distinct phases. The descriptive phase is used to represent the conflict. The prescriptive phase is used in two ways: (i) to visualize the effects of changes in parameters (,conflict resolution aid'), hopefully bringing the actors closer together, and (ii) as a tool to enhance the creative search for new alternatives (,alternative generation'). The conflict analysis process is illustrated by examining ex post a practical case study in water resource management. Copyright © 2002 John Wiley & Sons, Ltd. [source] Fluorescence and photoisomerization studies of p -nitrophenyl-substituted ethenylindolesJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 1 2006Anil K. Singh Abstract The synthesis, electronic absorption, fluorescence (,f, ,ex, ,f, ,f) and photoisomerization (,t,c, photostationary state composition) properties of 3-(4-nitrophenylethenyl- E)-NH-indole (1), 3-(4-nitrophenylethenyl- E)- N -ethylindole (2) and 3-(4-nitrophenyl ethenyl- E)- N -benzenesulfonylindole (3) in organic solvents of varying polarity are reported. The absorption maximum of these compounds undergoes a moderate red shift with increasing solvent polarity. However, the fluorescence maximum becomes highly red shifted with increasing solvent polarity. Whereas 1 and 2 show broad fluorescence bands, 3 exhibits dual fluorescence. Further, 1 and 2 fluoresce much more efficiently than 3. Correlation of the Stokes shift with solvent polarity parameters such as ,f and ET(30) and excited-state dipole moment indicate a highly polar excited state for 1,3. Time-resolved fluorescence studies show that the fluorescence decays are single- and multi-exponential type, depending on the solvent polarity. Further, 1 and 2 do not show photoisomerization on irradiation. However, 3 is photoactive and shows efficient photoisomerization in non-polar heptane. The sensitivity (,) of the photoreaction is determined in various solvent in terms of the Hammett plot, which showed that the excited states involved are electron deficient in nature and consequently stabilized more by an electron sufficient polar solvent and electron donating substituent. These results led us to suggest the existence of three types of excited states, namely the locally excited state, the intramolecular charge-transfer excited state and the conformationally relaxed intramolecular charge-transfer excited state in the photoprocesses of these compounds. Copyright © 2005 John Wiley & Sons, Ltd. [source] Biological Control of Botrytis cinerea Pers. ex Fr. in Strawberry by Paenibacillus polymyxaJOURNAL OF PHYTOPATHOLOGY, Issue 6 2001Article first published online: 20 DEC 200 [source] Synthesis of AB-type block copolymers containing benzoxazole and anthracene groups by ATRP and fluorescent propertyJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 17 2007Jian-Mei Lu Abstract Two functional monomers, methacrylic acid 4-(2-benzoxazol)-benzyl ester (MABE) containing the benzoxazole group and 4-(2-(9-anthryl))-vinyl-styrene (AVS) containing the anthracene group were synthesized by rational design. The MABE was polymerized via atom transfer radical polymerization (ATRP) using ethyl 2-bromoisobutyrate (EBIB) as initiator in CuBr/N,N,N,,N,,N,-pentamethyldiethylenetriamine (PMDETA) catalyst system; block copolymers poly(MABE- b -AVS) was obtained, which was conducted by using poly(MABE) as macro-initiator, AVS as the second monomer, and CuBr/PMDETA as catalyst. The constitute of two monomers in block copolymers poly(MABE- b -AVS) by ATRP could be adjusted, that is the constitute of the benzoxazole group and the anthracene group could be controlled in AB-type block copolymers. Moreover, the fluorescent properties of homopolymers poly(MABE) and block copolymers poly(MABE- b -AVS) were discussed herein. With the excitation at ,ex = 330 nm, the fluorescent emission spectrum of poly(MABE) solution showed emission at 375 nm corresponding to the benzoxazole-based part; with the same excitation, the fluorescent emission spectrum of poly(MABE- b -AVS) solution showed a broad peek at 330,600 nm when the monomer AVS to the total monomers mole ratio was 0.31, and the fluorescent emission spectrum of poly(MABE- b -AVS) in film state only showed one peak at 525 nm corresponding to the anthracene-based unit that indicated a complete energy transfer from the benzoxazole group to the anthracene group. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3894,3901, 2007 [source] Determination of some hydroxybenzoic acids and catechins in white wine samples by liquid chromatography with luminescence detectionJOURNAL OF SEPARATION SCIENCE, JSS, Issue 18 2006Rafael Carlos Rodríguez-Díaz Abstract A liquid chromatographic method with luminescence detection for the determination of eight phenolic compounds is reported. The method involves postcolumn derivatization with terbium(III). This derivatization is based on the reaction between phenolics and terbium(III) to form luminescent chelates, which were determined at ,ex 295 and ,em 545 nm using the fluorescence mode. The long wavelength emission of lanthanide chelates can minimize interferences from background sample matrix, which usually emit at shorter wavelengths. Also, the chromatographic separation allows the individual determination of phenolics, which cannot be done using the direct measurement of the fluorescence of their corresponding terbium chelates. Dynamic ranges of the calibration graphs and detection limits, obtained with standard solutions of analytes were (,g/mL): gallic acid (0.9,40, 0.3), protocatechuic acid (0.05,7, 0.016), catechin (0.2,40, 0.07), vanillic acid (0.25,40, 0.08), p -hydroxybenzoic acid (0.8,40, 0.25), syringic acid (0.17,40, 0.05), epicatechin (0.3,40, 0.09) and salicylic acid (0.07,12, 0.02). The precision was established at two concentration levels of each analyte and expressed as the percentage of RSD with values ranging between 1.0 and 6.5%. The practical usefulness of the method was demonstrated by the analysis of white wine samples, which were diluted two-fold and directly injected into the chromatographic system. The recovery values obtained ranged between 93.3 and 108.0%. 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