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Selected AbstractsAn enhanced level of motor cortical excitability during the control of human standingACTA PHYSIOLOGICA, Issue 3 2009C. D. Tokuno Abstract Aim:, The study examined the role of the motor cortex in the control of human standing. Methods:, Subjects (n = 15) stood quietly with or without body support. The supported standing condition enabled subjects to stand with a reduced amount of postural sway. Peripheral electrical stimulation, transcranial magnetic stimulation (TMS) or transcranial electrical stimulation (TES) was applied to elicit a soleus (SOL) H-reflex, or motor-evoked potentials (MEPs) in the SOL and the tibialis anterior (TA). Trials were grouped based on the standing condition (i.e. supported vs. normal) as well as sway direction (i.e. forward and backward) while subjects were standing normally. Results:, During normal when compared to supported standing, the SOL H-reflex was depressed (,11 ± 4%), while the TMS-evoked MEPs from the SOL and TA were facilitated (35 ± 11% for the SOL, 51 ± 15% for the TA). TES-evoked SOL and TA MEPs were, however, not different between the normal and supported standing conditions. The data based on sway direction indicated that the SOL H-reflex, as well as the SOL TMS- and TES-evoked MEPs were all greater during forward when compared to backward sway. In contrast, the TMS- and TES-evoked MEPs from the TA were smaller when swaying forward as compared to backward. Conclusions:, The results indicated the presence of an enhanced cortical excitability because of the need to control for postural sway during normal standing. The increased cortical excitability was, however, unlikely to be involved in an on-going control of postural sway, suggesting that postural sway is controlled at the spinal and/or subcortical levels. [source] Effect of the lactic acid bacterium Streptococcus thermophilus on stratum corneum ceramide levels and signs and symptoms of atopic dermatitis patientsEXPERIMENTAL DERMATOLOGY, Issue 5 2003Luisa Di Marzio Abstract:, A reduced amount of total ceramides could be responsible for functional abnormalities of the skin of atopic dermatitis (AD) patients. The ability of an experimental cream containing sonicated Streptococcus thermophilus to increase skin ceramide levels in healthy subjects has been previously reported. The aim of the present work was to investigate the effects of the topical administration of a S. thermophilus -containing cream on ceramide levels of stratum corneum from AD patients. A 2-week application of the cream, containing a sonicated preparation of the lactic acid bacterium S. thermophilus, in the forearm skin of 11 patients led to a significant and relevant increase of skin ceramide amounts, which could have resulted from the sphingomyelin hydrolysis through the bacterial sphingomyelinase. Moreover, in all patients the topical application of our experimental cream also resulted in the improvement of the signs and symptoms characteristic of AD skin (i.e. erythema, scaling, pruritus). [source] Investigation of critical inter-related factors affecting the efficacy of pulsed light for inactivating clinically relevant bacterial pathogensJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2010H.P. Farrell Abstract Aims:, To investigate critical electrical and biological factors governing the efficacy of pulsed light (PL) for the in vitro inactivation of bacteria isolated from the clinical environment. Development of this alternative PL decontamination approach is timely, as the incidence of health care,related infections remains unacceptably high. Methods and Results:, Predetermined cell numbers of clinically relevant Gram-positive and Gram-negative bacteria were inoculated separately on agar plates and were flashed with ,60 pulses of broad-spectrum light under varying operating conditions, and their inactivation measured. Significant differences in inactivation largely occurred depending on the level of the applied lamp discharge energy (range 3·2,20 J per pulse), the amount of pulsing applied (range 0,60 pulses) and the distance between light source and treatment surface (range 8,20 cm) used. Greater decontamination levels were achieved using a combination of higher lamp discharge energies, increased number of pulses and shorter distances between treatment surface and the xenon light source. Levels of microbial sensitivity also varied depending on the population type, size and age of cultures treated. Production of pigment pyocynanin and alginate slime in mucoid strains of Pseudomonas aeruginosa afforded some protection against lethal action of PL; however, this was evident only by using a combination of reduced amount of pulsing at the lower lamp discharge energies tested. A clear pattern was observed where Gram-positive bacterial pathogens were more resistant to cidal effects of PL compared to Gram negatives. While negligible photoreactivation of PL-treated bacterial strains occurred after full pulsing regimes at the different lamp discharge energies tested, some repair was evident when using a combination of reduced pulsing at the lower lamp discharge energies. Strains harbouring genes for multiple resistances to antibiotics were not significantly more resistant to PL treatments. Slight temperature rises (,4·2°C) were measured on agar surfaces after extended pulsing at higher lamp discharge energies. Presence of organic matter on treatment surface did not significantly affect PL decontamination efficacy, nor did growth of PL-treated bacteria on selective agar diminish survival compared to similarly treated bacteria inoculated and enumerated on nonselective agar plates. Conclusions:, Critical inter-related factors affecting the effective and repeatable in vitro decontamination performance of PL were identified during this study that will aid further development of this athermal process technology for applications in health care and in industry. Very rapid reductions (c. 7 log10 CFU cm,2 within ,10 pulses) occurred using discharge energy of 20 J for all tested clinically relevant bacteria under study when treated at 8 cm distance from xenon light source. While no resistant flora is expected to develop for treatment of microbial pathogens on two-dimensional surfaces, careful consideration of scale up factors such as design and operational usage of this PL technique will be required to assure operator safety. Significance and Impact of the Study:, Findings and conclusions derived from this study will enable further development and optimization of this decontamination technique in health care and in food preparation settings, and will advance the field of nonthermal processing technologies. [source] Optimization of growth medium for the production of ,-amylase from Bacillus amyloliquefaciens using response surface methodologyJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 4 2006M Saban Tanyildizi Abstract The optimization of nutrient levels for the production of ,-amylase by Bacillus amyloliquefaciens was carried out using response surface methodology (RSM) based on the 23 factorial central composite design (CCD). This procedure limited the number of actual experiments performed while allowing for possible interactions between three components. RSM was adopted to derive a statistical model for the effect of starch, peptone and yeast extract (YE) on ,-amylase production. The P -value of the coefficient for linear effects of starch and YE concentration was <0.0001, suggesting that this was the principal experimental variable, having the greatest effect on the production of ,-amylase. The optimal combinations of media constituents for maximum ,-amylase production were determined as 12.61 g L,1 starch, 2.83 g L,1 peptone and 1.25 g L,1 YE. The optimization of the medium resulted not only in a 34% higher enzyme activity than unoptimized medium but also in a reduced amount of the required medium constituents. Copyright © 2006 Society of Chemical Industry [source] Small-Diameter Implants: Indications and ContraindicationsJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 4 2000MITHRIDADE DAVARPANAH MD ABSTRACT The choice of implant diameter depends on the type of edentulousness, the volume of the residual bone, the amount of space available for the prosthetic reconstruction, the emergence profile, and the type of occlusion. Small-diameter implants are indicated in specific clinical situations, for example, where there is reduced interradicular bone or a thin alveolar crest, and for the replacement of teeth with small cervical diameter. Before using a small-diameter implant, the biomechanical risk factors must be carefully analyzed. Preliminary reports of this type of implant show good short- and medium-term results. CLINICAL SIGNIFICANCE Specific clinical situations indicate the use of small-diameter implants: a reduced amount of bone (thin alveolar crest) and where the replacement tooth requires a small cervical diameter. In some cases, the use of small-diameter implants avoids bone reconstruction. [source] Efficient cloning of plant genomes into bacterial artificial chromosome (BAC) libraries with larger and more uniform insert sizePLANT BIOTECHNOLOGY JOURNAL, Issue 3 2004Boulos Chalhoub Summary The construction of bacterial artificial chromosome (BAC) libraries remains relatively complex and laborious, such that any technological improvement is considered to be highly advantageous. In this study, we addressed several aspects that improved the quality and efficiency of cloning of plant genomes into BACs. We set the ,single tube vector' preparation method with no precipitation or gel electrophoresis steps, which resulted in less vector DNA damage and a remarkable two- to threefold higher transformation efficiency compared with other known vector preparation methods. We used a reduced amount of DNA for partial digestion (up to 5 µg), which resulted in less BAC clones with small inserts. We performed electrophoresis in 0.25 × TBE (Tris, boric acid, ethylenediaminetetraacetic acid) buffer instead of 0.5 × TBE, which resulted in larger and more uniformly sized BAC inserts and, surprisingly, a two- to threefold higher transformation efficiency, probably due to less contamination with borate ions. We adopted a triple size selection that resulted in an increased mean insert size of up to 70 kb and a transformation efficiency comparable with that of double size selection. Overall, the improved protocol presented in this study resulted in a five- to sixfold higher cloning efficiency and larger and more uniformly sized BAC inserts. BAC libraries with the desired mean insert size (up to 200 kb) were constructed from several plant species, including hexaploid wheat. The improved protocol will render the construction of BAC libraries more available in plants and will greatly enhance genome analysis, gene mapping and cloning. [source] Role of group A Streptococcus HtrA in the maturation of SpeB proteasePROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 24 2007Jason N. Cole Abstract The serine protease high-temperature requirement A (HtrA) (DegP) of the human pathogen Streptococcus pyogenes (group A Streptococcus; GAS) is localized to the ExPortal secretory microdomain and is reportedly essential for the maturation of cysteine protease streptococcal pyrogenic exotoxin B (SpeB). Here, we utilize HSC5 (M5 serotype) and the in-frame isogenic mutant HSC5,htrA to determine whether HtrA contributes to the maturation of other GAS virulence determinants. Mutanolysin cell wall extracts and secreted proteins were arrayed by 2-DE and identified by MALDI-TOF PMF analysis. HSC5,htrA had elevated levels of cell wall-associated M protein, whilst the supernatant had higher concentrations of M protein fragments and a reduced amount of mature SpeB protease, compared to wild-type (WT). Western blot analysis and protease assays revealed a delay in the maturation of SpeB in the HSC5,htrA supernatant. HtrA was unable to directly process SpeB zymogen (proSpeB) to the active form in vitro. We therefore conclude that HtrA plays an indirect role in the maturation of cysteine protease SpeB. [source] Effects of the Cardiff Bay tidal barrage on the abundance, ecology and behaviour of shelducks Tadorna tadornaAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2009Peter N. Ferns Abstract 1.Closure of the Taff/Ely Estuary by the Cardiff Bay barrage in 1999 resulted in the replacement of intertidal mudflats by a permanent freshwater lake. This led to an 89% reduction in the population of shelducks Tadorna tadorna. 2.The birds switched from foraging mainly for Nereis diversicolor and Hydrobia ulvae by scything with the bill as they walked across the mudflats at low tide, to feeding on benthic chironomid midge larvae while swimming in shallow water around the margins of the lake. 3.The population decline occurred as a consequence of a decrease in the area available for foraging,,,from about 1,km2 of mudflats to about 0.1,km2 of water shallow enough for shelducks to reach the bottom when dabbling, head dipping and upending. 4.Contrary to expectation, the amount of time shelducks spent feeding was similar pre- and post-barrage, and their body and plumage condition improved. 5.A tidal rhythm in activity persisted, with a reduced amount of feeding at high tide, probably because of the slight rise in water levels that sometimes occurred at this time. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effects of angiotensin II blockade on inflammation-induced alterations of pharmacokinetics and pharmacodynamics of calcium channel blockersBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2008S Hanafy Background and purpose: Inflammation elevates plasma verapamil concentrations but diminishes pharmacological response. Angiotensin II is a pro-inflammatory mediator. We examined the effect of angiotensin II receptor blockade on the pharmacokinetics and pharmacodynamics of verapamil, as well as the binding properties and amounts of its target protein in calcium channels, in a rat model of inflammation. Experimental approach: We used 4 groups of male Sprague,Dawley rats (220,280 g): inflamed-placebo, inflamed-treated, control-placebo and control-treated. Inflammation as pre-adjuvant arthritis was induced by injecting Mycobacterium butyricum on day 0. From day 6 to 12, 30 mg kg,1 oral valsartan or placebo was administered twice daily. On day 12, a single oral dose of 25 mg kg,1 verapamil was administered and prolongation of the PR interval measured and plasma samples collected for verapamil and nor-verapamil analysis. The amounts of the target protein Cav1.2 subunit of L-type calcium channels in heart was measured by Western blotting and ligand binding with 3H-nitrendipine. Key results: Inflammation reduced effects of verapamil, although plasma drug concentrations were increased. This was associated with a reduction in ligand binding capacity and amount of the calcium channel target protein in heart extracts. Valsartan significantly reversed the down-regulating effect of inflammation on verapamil's effects on the PR interval, and the lower level of protein binding and the decreased target protein. Conclusions and implications: Reduced responses to calcium channel blockers in inflammatory conditions appeared to be due to a reduced amount of target protein that was reversed by the angiotensin II antagonist, valsartan. British Journal of Pharmacology (2008) 153, 90,99; doi:10.1038/sj.bjp.0707538; published online 29 October 2007 [source] Birth defects caused by mutations in human GLI3 and mouse Gli3 genesCONGENITAL ANOMALIES, Issue 1 2010Ichiro Naruse ABSTRACT GLI3 is the gene responsible for Greig cephalopolysyndactyly syndrome (GCPS), Pallister,Hall syndrome (PHS) and Postaxial polydactyly type-A (PAP-A). Genetic polydactyly mice such as Pdn/Pdn (Polydactyly Nagoya), XtH/XtH (Extra toes) and XtJ/XtJ (Extra toes Jackson) are the mouse homolog of GCPS, and Gli3tmlUrtt/Gli3tmlUrt is produced as the mouse homolog of PHS. In the present review, relationships between mutation points of GLI3 and Gli3, and resulting phenotypes in humans and mice are described. It has been confirmed that mutation in the upstream or within the zinc finger domain of the GLI3 gene induces GCPS; that in the post-zinc finger region including the protease cleavage site induces PHS; and that in the downstream of the GLI3 gene induces PAP-A. A mimicking phenomenon was observed in the mouse homolog. Therefore, human GLI3 and mouse Gli3 genes have a common structure, and it is suggested here that mutations in the same functional regions produce similar phenotypes in human and mice. The most important issue might be that GCPS and PHS exhibit an autosomal dominant trait, but mouse homologs, such as Pdn/Pdn, XtH/XtH, XtJ/XtJ and Gli3tmlUrt/Gli3tmlUrt, are autosomal recessive traits in the manifestation of similar phenotypes to human diseases. It is discussed here how the reduced amounts of the GLI3 protein, or truncated mutant GLI3 protein, disrupt development of the limbs, head and face. [source] Decreased virulence of a strain of Pseudomonas aeruginosa O12 overexpressing a chromosomal type 1 ,-lactamase could be due to reduced expression of cell-to-cell signaling dependent virulence factorsFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2000Françoise Ramisse Abstract Pseudomonas aeruginosa produces a large variety of virulence factors and is characterized by its capacity to rapidly develop resistance when exposed to antibiotics. In order to evaluate a possible correlation between acquired resistance to antibiotics and virulence, we examined the virulence of four isogenic variants of P. aeruginosa O12 that differ in their resistance phenotypes to various ,-lactam antibiotics in a mouse model of acute pneumonia. Strains overproducing a chromosomal type 1 ,-lactamase were less virulent in both immunocompetent and immunosuppressed animals. Whereas the production of the exopolysaccharide alginate was similar between the four strains, extracellular virulence factors (elastase, rhamnolipid) that are controlled by the cell-to-cell signaling system circuit were detected in reduced amounts in the supernatant of the two isolates overproducing type 1 ,-lactamase. These results suggest that strains overexpressing the chromosomal type 1 ,-lactamase could be less virulent because of a reduction of cell-to-cell signaling dependent virulence factor production. [source] KlADH3, a gene encoding a mitochondrial alcohol dehydrogenase, affects respiratory metabolism and cytochrome content in Kluyveromyces lactisFEMS YEAST RESEARCH, Issue 8 2006Michele Saliola Abstract A Kluyveromyces lactis strain, harbouring KlADH3 as the unique alcohol dehydrogenase (ADH) gene, was used in a genetic screen on allyl alcohol to isolate mutants deregulated in the expression of this gene. Here we report the characterization of some mutants that lacked or had highly reduced amounts of KlAdh3p activity; in addition, these mutants showed alterations in glucose metabolism, reduced respiration and reduced cytochrome content. Our results confirm that the KlAdh3p activity contributes to the reoxidation of cytosolic NAD(P)H feeding the respiratory chain through KlNdi1p, the mitochondrial internal transdehydrogenase. The low levels of KlAdh3p in two of the mutants were associated with mutations in KlSDH1, one of the genes of complex II, suggesting signalling between the respiratory chain and expression of the KlADH3 gene. [source] Embedded Shape-Memory Alloy Wires for Improved Performance of Self-Healing Polymers,ADVANCED FUNCTIONAL MATERIALS, Issue 15 2008Eva L. Kirkby Abstract We report the first measurements of self-healing polymers with embedded shape-memory alloy (SMA) wires. The addition of SMA wires shows improvements of healed peak fracture loads by up to a factor of 1.6, approaching the performance of the virgin material. Moreover, the repairs can be achieved with reduced amounts of healing agent. The improvements in performance are due to two main effects: (i) crack closure, which reduces the total crack volume and increases the crack fill factor for a given amount of healing agent and (ii) heating of the healing agent during polymerization, which increases the degree of cure of the polymerized healing agent. [source] Monocyte cytokine and costimulatory molecule expression in patients infected with Leishmania mexicanaPARASITE IMMUNOLOGY, Issue 3 2007G. CARRADA SUMMARY Leishmania mexicana causes localized and diffuse cutaneous leishmaniasis. Patients with localized cutaneous leishmaniasis (LCL) develop a benign disease, whereas patients with diffuse cutaneous leishmaniasis (DCL) suffer from a progressive disease associated with anergy of the cellular response towards Leishmania antigens. We evaluated the production of the interleukins (IL) IL-12, IL-15, IL-18 and tumour necrosis factor-, (TNF-,) and the expression of the costimulatory molecules CD40, B7-1 and B7-2 in monocytes from LCL and DCL patients, stimulated in vitro with Leishmania mexicana lipophosphoglycan (LPG) for 18 h. LCL monocytes significantly increased TNF-,, IL-15 and IL-18 production, and this increase was associated with reduced amounts of IL-12. DCL monocytes produced no IL-15 or IL-18 and showed a decreasing tendency of TNF-, and IL-12 production as the severity of the disease increased. No difference was observed in the expression of CD40 and B7-1 between both groups of patients, yet B7-2 expression was significantly augmented in DCL patients. It remains to be established if this elevated B7-2 expression in DCL patients is cause or consequence of the Th2-type immune response that characterizes these patients. These data suggest that the diminished ability of the monocytes from DCL patients to produce cell-activating innate proinflammatory cytokines when stimulated with LPG is a possible cause for disease progression. [source] The temperature response of photosynthesis in tobacco with reduced amounts of RubiscoPLANT CELL & ENVIRONMENT, Issue 4 2008DAVID S. KUBIEN ABSTRACT The reasons for the decline in net CO2 assimilation (A) above its thermal optimum are controversial. We tested the hypothesis that increasing the ratio of Rubisco activase to Rubisco catalytic site concentration would increase the activation state of Rubisco at high temperatures. We measured photosynthetic gas exchange, in vivo electron transport (J) and the activation state of Rubisco between 15 and 45 °C, at 38 and 76 Pa ambient CO2, in wild-type (WT) and anti- rbcS tobacco. The Rubisco content of the anti- rbcS lines was 30% (S7-1) or 6% (S7-2) of WT, but activase levels were the same in the three genotypes. Anti- rbcS plants had lower A than WT at all temperatures, but had a similar thermal optimum for photosynthesis as WT at both CO2 levels. In WT plants, Rubisco was fully activated at 32 °C, but the activation state declined to 64% at 42 °C. By contrast, the activation state of Rubisco was above 90% in the S7-1 line, between 15 and 42 °C. Both A and J declined about 20% from Topt to the highest measurement temperatures in WT and the S7-1 line, but this was fully reversed after a 20 min recovery at 35 °C. At 76 Pa CO2, predicted rates of RuBP regeneration-limited photosynthesis corresponded with measured A in WT tobacco at all temperatures, and in S7-1 tobacco above 40 °C. Our observations are consistent with the hypothesis that the high temperature decline in A in the WT is because of an RuBP regeneration limitation, rather than the capacity of Rubisco activase to maintain high Rubisco activation state. [source] Tobacco bZIP transcription factor TGA2.2 and related factor TGA2.1 have distinct roles in plant defense responses and plant developmentTHE PLANT JOURNAL, Issue 1 2005Corinna Thurow Summary Salicylic acid (SA) is a crucial internal signaling molecule needed for the induction of plant defense responses upon attack of a variety of pathogens. Basic leucine zipper transcription factors of the TGA family bind to activating sequence-1 (as-1) -like elements which are SA-responsive cis elements found in promoters of ,immediate early' and ,late' SA-inducible genes. TGA2.2 constitutes the main component of tobacco as -1 -binding factor-1 (ASF-1). TGA2.1, which differs from TGA2.2 by being able to activate transcription in yeast, constitutes a minor fraction of the complex. Both proteins interact with NPR1, a protein essential for SA inducibility of ,late' genes. Here we demonstrate using dsRNAi mediated gene silencing that reducing the amount of TGA2.2 and TGA2.1 correlates with a significant decrease in ASF-1 activity and with a decreased inducibility of both ,immediate early' and ,late' genes. In contrast, reducing the amount of TGA2.1 alone had no effect on the expression of these target genes suggesting that TGA2.1 is dispensable for SA-inducible gene expression from the as-1 element. Expression of a TGA2.2 mutant unable to form heterodimers with the endogenous pool of TGA factors led to reduced SA-inducibility of ,immediate early' gene Nt103, indicating that the native leucine zipper is important for the protein to act positively on transcription. Plants with reduced amounts of TGA2.1 developed petal like stamens indicating a regulatory role of TGA2.1 in defining organ identity in tobacco flowers. A model is suggested that unifies conflicting results on the function of tobacco TGA factors with respect to activation of the ,late'PR-1a promoter. [source] | ||||||||||||||||