Home About us Contact
|
Home About us Contact | ||
|
|
||
mM NaCl (mm + nacl)
Selected AbstractsDouble-Blind, Randomized, Placebo-Controlled Pilot Study of the Safety and Efficacy of Myobloc (Botulinum Toxin Type B) for the Treatment of Palmar HyperhidrosisDERMATOLOGIC SURGERY, Issue 3 2005Leslie Baumann MD Background Palmar hyperhidrosis is a problem of unknown etiology that affects patients both socially and professionally. Botulinum toxin type B (Myobloc), approved by the Food and Drug Administration for use in the treatment of cervical dystonia in the United States in December 2000, has subsequently been used effectively in an off-label indication to treat hyperhidrosis. There are sparse data, however, in the literature evaluating the safety and efficacy of BTX-B for the treatment of palmar hyperhidrosis. Objective We evaluated the safety and efficacy of Myobloc in the treatment of bilateral palmar hyperhidrosis. This was a double-blind, randomized, placebo-controlled study to report on the safety and efficacy of Myobloc. Methods Twenty participants (10 men, 10 women) diagnosed with palmar hyperhidrosis were injected with either Myobloc (5,000 U per palm) or a 1.0 mL vehicle (100 mM NaCl, 10 mM succinate, and 0.5 mg/mL human albumin) into bilateral palms (15 Myobloc, 5 placebo). The participants were followed until sweating returned to baseline levels. The main outcome measures were safety, efficacy versus placebo, and duration of effect. Results A significant difference was found in treatment response at day 30, as determined by participant assessments, between 15 participants injected with Myobloc and 3 participants injected with placebo. The duration of action, calculated in the 17 participants who received Myobloc injections and completed the study, ranged from 2.3 to 4.9 months, with a mean duration of 3.8 months. The single most reported adverse event was dry mouth or throat, which was reported by 18 of 20 participants. The adverse event profile also included indigestion or heartburn (60%), excessively dry hands (60%), muscle weakness (60%), and decreased grip strength (50%). Conclusion Myobloc proved to be efficacious for the treatment of palmar hyperhidrosis. Myobloc had a rapid onset, with most participants responding within 1 week. The duration of action ranged from 2.3 to 4.9 months, with a mean of 3.8 months. The adverse event profile included dry mouth, indigestion or heartburn, excessively dry hands, muscle weakness, and decreased grip strength. MYOBLOC WAS PROVIDED FOR THIS STUDY BY ELAN PHARMACEUTICALS. [source] Plant,Water Relations of Kidney Bean Plants Treated with NaCl and Foliarly Applied GlycinebetaineJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2002C. M. L. Lopez Salinity is at present one of the most serious environmental problems influencing crop growth. It has been extensively demonstrated that salinity affects several physiological processes in the plant, including the plant,water relations of most salt-sensitive crops species. In this study, the effects of salinity on the plant,water relations of kidney bean (Phaseolus vulgaris L.) and the possibility that foliarly applied glycinebetaine improves these water relations are examined. Kidney bean plants were grown in a greenhouse and treated with 0, 30, 50 and 100 mM NaCl, combined with 0, 10 and 30 mM glycinebetaine in foliar applications. Increased salinity levels decreased stomatal conductance, photosynthetic rate, transpiration and leaf relative water content in the 30, 50 and 100 mM treatments relative to the control treatment. Glycinebetaine applications of 10 mM increased stomatal conductance at 50 mM NaCl, ameliorating significantly the effect of salinity on water relations through increases in the leaf relative water content. At 100 mM NaCl, 30 mM glycinebetaine applications in particular contributed to osmotic stress, and had an adverse effect on plants. Our experiment suggests that glycinebetaine can be used as an alternative treatment to reduce the effects of salt stress on the water relations of salt-sensitive plants, but only to limited salinity levels. Furthermore, the improvement in the water status of kidney beans was dose dependent, suggesting that the concentration of glycinebetaine essential for the survival of salt-sensitive plants is species specific and must be determined individually for each plant species. Pflanzen,Wasser-Beziehungen von NaCl-behandelten und mit Glycinbetain besprühten Blättern von Gartenbohnenpflanzen Versalzung ist zur Zeit eine der am meisten wirksamen Umweltprobleme im Hinblick auf das Wachstum von Kulturpflanzen. Es hat umfangreiche Untersuchungen gegeben, die Versalzungswirkungen in ihrem Einfluss auf zahlreiche physiologische Vorgänge in der Pflanze zu untersuchen; hierbei wurden auch die Pflanzen,Wasser-Beziehungen von hochsalzempfindlichen Pflanzenarten berück-sichtigt. In dieser Untersuchung wurden die Einflüsse der Versalzung auf die Pflanzen,Wasser-Beziehungen bei Buschbohnen (Phaseolus vulgaris L.) und die Möglichkeit über Blattbesprühungen mit Glycinbetain die Wasser-Beziehungen zu verbessern, untersucht. Die Buschbohnen wurden im Gewächshaus angezogen und mit 0, 30, 50 mM NaCl in Kombination mit 0, 10, 30 mM Glycinbetain Blattbehandlungen angezogen. Eine Erhöhung der Versalzung führte zu einer Abnahme der stomatären Konduktanz, der Photosyntheserate, der Transpiration und des relativen Blattwassergehaltes bei den Behandlungen mit 30, 50 und 100 mM im Vergleich zur Kontrolle. Glysinbetainanwendungen von 10mM erhöhten die stomatäre Konduktanz bei 50 mM NaCl und verbesserten signifikant den ungünstigen Einfluss der Versalzung auf die Wasser-Beziehungen über eine Erhöhung des relativen Blattwassergehaltes. Verwendung von 100 mM NaCl und 30 mM GB trug zu dem osmotischen Streß durch Versalzung bei und hatten einen ungünstigen Einfluss auf die Pflanzen. Unser Experiment weist darauf hin, dass Glycinbetain eine alternative Möglichkeit ist, um die Einflüsse des Salzstresses auf die Wasser-Beziehungen von salzempfindlichen Pflanzen abzuschwächen; es bestehen aber Begrenzungen bezüglich des Versalzungsgrades, bei denen eine günstige Wirkung nachgewiesen werden kann. Ausserdem ist die Verbesserung im Wasserzustand der Buschbohnen von der Anwendungsstärke abhängig, so dass die Konzentration von GB wesentlich für das Überleben der salzempfindlichen Pflanzenart spezifisch ist und für jede Pflanzenart untersucht werden. [source] Core-Shell Biopolymer Nanoparticles Produced by Electrostatic Deposition of Beet Pectin onto Heat-Denatured ,-Lactoglobulin AggregatesJOURNAL OF FOOD SCIENCE, Issue 6 2008R. Santipanichwong ABSTRACT:, The purpose of this study was to produce and characterize core-shell biopolymer particles based on electrostatic deposition of an anionic polysaccharide (beet pectin) onto amphoteric protein aggregates (heat-denatured ,-lactoglobulin [,-lg]). Initially, the optimum conditions for forming stable protein particles were established by thermal treatment (80 °C for 15 min) of 0.5 wt%,-lg solutions at different pH values (3 to 7). After heating, stable submicron-sized (d= 100 to 300 nm) protein aggregates could be formed in the pH range from 5.6 to 6. Core-shell biopolymer particles were formed by mixing a suspension of protein aggregates (formed by heating at pH 5.8) with a beet pectin solution at pH 7 and then adjusting the pH to values where the beet pectin is adsorbed (< pH 6). The impact of pH (3 to 7) and salt concentration (0 to 250 mM NaCl) on the properties of the core-shell biopolymer particles formed was then established. The biopolymer particles were stable to aggregation from pH 4 to 6, but aggregated at lower pH values because they had a relatively small ,-potential. The biopolymer particles remained intact and stable to aggregation up to 250 mM NaCl at pH 4, indicating that they had good salt stability. The core-shell biopolymer particles prepared in this study may be useful for encapsulation and delivery of bioactive food components or as substitutes for lipid droplets. [source] Effects of NaCl Concentration on Salting-in and Dilution During Salting-out on Soy Protein FractionationJOURNAL OF FOOD SCIENCE, Issue 4 2006N. A. Deak ABSTRACT:, Glycinin and ,-conglycinin are the main storage proteins in soybeans that can be fractionated by using alkali extraction, SO2, salting-in with NaCl, salting-out by dilution and pH adjustment to produce a glycinin-rich fraction, a ,-conglycinin,rich fraction, and an intermediate fraction, which is a mixture of the two proteins. Two different strategies were employed to optimize the procedure to achieve high efficiency in recovering the ,-conglycinin,rich fraction. The first strategy was to optimize salting-in effects of NaCl, and the effects of NaCl concentration on the yields and purities of the protein fractions were investigated. The maximum protein yield of the ,-conglycinin,rich fraction was obtained at 500 mM NaCl, but at the expense of purity. The optimum NaCl concentration was 250 mM, at which good protein yield (18.5%) and purity (84.5%) were achieved. At higher NaCl concentrations, the protein yields of the intermediate fractions were significantly lower, and the protein loss in the whey fraction increased. The second strategy was to improve the salting-out step for the ,-conglycinin,rich fraction. At 0- and 0.5-fold dilution, the purities and yields of the ,-conglycinin,rich fractions were significantly lower than at 1.0- and 2.0-fold dilution. There were no differences in protein yields or purities when using 1.0- or 2.0-fold dilution. According to these results, the recommended NaCl concentration for the salting-in step is 250 mM and the dilution factor for salting-out is 1.0. [source] Role of pH and Ionic Strength on Water Relationships in Washed Minced Chicken-breast Muscle GelsJOURNAL OF FOOD SCIENCE, Issue 3 2003H.G. Kristinsson ABSTRACT The relationship between pH, ionic strength, and water balance of chicken-breast muscle gels was investigated. An increase in gel pH (pH 6.4 to 7.4) without added NaCl led to dramatic increases in water-holding capacity and water uptake (P < 0.05). Gels at 150 mM NaCl exhibited less ability to adsorb water than salt-free gels (P < 0.05 at pH 6.8 to 7.4) and had lower water-holding capacities (P < 0.05) and fold scores at and below pH 7. Varying salt concentration of the gel-bathing solutions had dramatic effect on the water uptake of the gels. The results show that strong water-absorbing gels can be produced at low ionic strengths and suggest that the negative charge of the muscle proteins is the driving force for water uptake and retention. [source] Optimizing Preparation Conditions for Heat-denatured Whey Protein Solutions to be Used as Cold-gelling IngredientsJOURNAL OF FOOD SCIENCE, Issue 2 2000C.M. Bryant ABSTRACT: Heat-denatured whey protein solutions are used to make ingredients that gel at low temperatures. This study examines the influence of holding temperature (65 to 90°C), holding time (5 to 30 min), protein concentration (2 to 12 wt%) and pH (3 to 8) on the rheology and appearance of heat-denatured whey protein solutions. The optimum preparation conditions required to produce non-gelled transparent solutions of heat-denatured proteins were established. The rate of cold-gelation after the addition of 200 mM NaCl to the heat-denatured whey protein solutions increased as their initial viscosity increased. It was possible to produce gels with different cold-gelling characteristics by altering the thermal preparation conditions. [source] Water-elutability of nucleic acids from metal-chelate affinity adsorbents: enhancement by control of surface charge density,JOURNAL OF MOLECULAR RECOGNITION, Issue 4 2006Joseph Y. Fu Abstract Immobilized metal affinity chromatography (IMAC) is widely used for purification of proteins, especially "hexahistidine-tagged" recombinant proteins. We previously demonstrated the application of IMAC to selective capture of nucleic acids, including RNA, selectively-denatured genomic DNA, and PCR primers through interactions with purine bases exposed in single-stranded regions. We also found that the binding affinity of nucleic acids for IMAC adsorbents can be increased several-fold by addition of 20 volume% of neutral additives such as ethanol or DMSO. In the present work, it is demonstrated that bound nucleic acids can be effectively eluted with water instead of the usual imidazole-containing competitive eluants, when the surface density of negative charges is enhanced by operation at alkaline pH, or by deliberate metal-underloading of the anionic chelating ligands. With enhanced negative surface charge density, nucleic acid adsorption can be made strongly dependent on the presence of adsorption-promoting additives and/or repulsion-shielding salts, and removal of these induces elution. Complete water-elutability is demonstrated for baker's yeast RNA bound to 10% Cu(II)- underloaded IDA Chelating Sepharose in a binding buffer of 20,mM HEPES, 240,mM NaCl, pH,7. Water elutability will significantly enhance the utility of IMAC in nucleic acid separations. Copyright © 2006 John Wiley & Sons, Ltd. [source] Decline in leaf growth under salt stress is due to an inhibition of H+ -pumping activity and increase in apoplastic pH of maize leavesJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2009Britta Pitann Abstract In this study, salt-induced changes in the growth rate of maize (Zea mays L.) were investigated during the first phase of salt stress. Leaf growth was reduced in the presence of 100 mM NaCl, and effects were more pronounced for the salt-sensitive cv. Pioneer 3906 in comparison to the hybrid SR03. While hydrolytic activity of plasma membrane remained unaffected, H+ -pumping activity was reduced by 47% in Pioneer 3906, but was unchanged in SR03. Changes in apoplastic pH were detected by ratiometric fluorescence microscopy using the fluorescent dye fluorescein isothiocyanate-dextran (50 mM). Pioneer 3906 responded with an increase of 0.2 pH units in contrast to SR03 for which no apoplastic alkalization was found. With respect to the hypothesis that the apoplastic pH is influenced by salinity, it is suggested that salt resistance is partly achieved due to efficient H+ -ATPase proton pumping, which results in cell-wall acidification and loosening. [source] Salt-resistant and salt-sensitive wheat genotypes show similar biochemical reaction at protein level in the first phase of salt stressJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2006Muhammad Saqib Abstract Salinity has a two-phase effect on plant growth, an osmotic effect due to salts in the outside solution and ion toxicity in a second phase due to salt build-up in transpiring leaves. To elucidate salt-resistance mechanisms in the first phase of salt stress, we studied the biochemical reaction of salt-resistant and salt-sensitive wheat (Triticum aestivum L.) genotypes at protein level after 10 d exposure to 125 mM,NaCl salinity (first phase of salt stress) and the variation of salt resistance among the genotypes after 30 d exposure to 125 mM,NaCl salinity (second phase of salt stress) in solution culture experiments in a growth chamber. The three genotypes differed significantly in absolute and relative shoot and root dry weights after 30 d exposure to NaCl salinity. SARC-1 produced the maximum and 7-Cerros the minimum shoot dry weights under salinity relative to control. A highly significant negative correlation (r2 = ,0.99) was observed between salt resistance (% shoot dry weight under salinity relative to control) and shoot Na+ concentration of the wheat genotypes studied. However, the salt-resistant and salt-sensitive genotypes showed a similar biochemical reaction at the level of proteins after 10 d exposure to 125 mM NaCl. In both genotypes, the expression of more than 50% proteins was changed, but the difference between the genotypes in various categories of protein change (up-regulated, down-regulated, disappeared, and new-appeared) was only 1%,8%. It is concluded that the initial biochemical reaction to salinity at protein level in wheat is an unspecific response and not a specific adaptation to salinity. [source] Does H+ pumping by plasmalemma ATPase limit leaf growth of maize (Zea mays) during the first phase of salt stress?JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2005Christian Zörb Abstract In the first phase of salt stress, growth of plants is impaired mainly by osmotic stress. To elucidate the effect of NaCl salinity on elongation growth of maize leaves in the first phase of salt stress, we investigated the effect of NaCl on gene expression and activity of the plasmalemma H+ ATPase of elongating leaves of maize (Zea mays L.). Treatment of maize plants with 125 mM NaCl for 3 d decreased leaf growth relative to control plants (1 mM NaCl). Whereas H+ ATPase hydrolytic activity was unaffected, the ability of the H+ ATPase to establish a pH gradient was strongly reduced. Total mRNA of plasmalemma H+ ATPase was slightly increased. However, mRNA of the ATPase isoform MHA1 was significantly reduced and ATPase isoform MHA4 was strongly increased at the mRNA level. Synthesis of total H+ ATPase protein was unchanged as revealed by western blot. The results indicate that reduced pumping of H+ ATPase in leaf plasmalemma under salt stress may be caused by a switch to gene expression of the specific isoform MHA4, which shows inferior H+ -pumping efficiency in comparison to isoforms expressed under control conditions. We propose that reduced H+ pumping of plasmalemma H+ ATPase is involved in the reduction of leaf growth of maize during the first phase of salt stress. Limitiert die H+ -Pumpaktivität der Plasmalemma-ATPase das Blattwachstum von Mais (Zea mays) während der ersten Phase eines Salzstresses? In der ersten Phase eines Salzstresses wird das Pflanzenwachstum hauptsächlich durch osmotischen Stress beeinträchtigt. Zur Klärung des Einflusses der NaCl-Salinität auf das Streckungswachstum von Maisblättern in der ersten Phase eines Salzstresses wurde der Einfluss von NaCl auf die Genexpression und die Aktivität der H+ -ATPase im Plasmalemma von unter Salzstress wachsenden Maisblättern (Zea mays L.) untersucht. Dreitägige Behandlung von Maispflanzen mit 125 mM NaCl verminderte im Vergleich zu Kontrollpflanzen (1 mM NaCl) das Blattwachstum. Während die hydrolytische H+ -ATPase-Aktivität unbeeinflusst blieb, wurde die Fähigkeit, einen pH-Gradienten aufzubauen, stark reduziert. Die Gesamt-mRNA der H+ -ATPase war unverändert. Während jedoch die ATPase-Isoform MHA1 signifikant vermindert war, wurde die Isoform MHA4 auf dem mRNA-Niveau stark erhöht. Die Western-Blot-Analyse zeigte keine Veränderung der Menge des Gesamtproteins der H+ -ATPase. Unsere Ergebnisse sprechen dafür, dass die reduzierte Fähigkeit der H+ -ATPase im Plasmalemma von unter Salzstress gewachsenen Blättern einen pH-Gradienten aufzubauen, durch Genexpression der spezifischen Isoform MHA4 verursacht wird. Diese Isoform weist eine geringere H+ -Pumpeffizienz im Vergleich zu Isoformen auf, die unter Kontrollbedingungen gebildet werden. Wir schlagen daher vor, dass die reduzierte Fähigkeit der H+ -ATPase einen pH-Gradienten aufzubauen, an der Verminderung des Blattwachstums von Mais in der ersten Phase des Salzstresses beteiligt ist. [source] Sensitivity of Actinobacillus actinomycetemcomitans and Capnocytophaga spp. to the bactericidal action of LL-37: a cathelicidin found in human leukocytes and epitheliumMOLECULAR ORAL MICROBIOLOGY, Issue 4 2000D. Tanaka The bactericidal activity of synthetic LL-37, a cathelicidin, was assessed against Actinobacillus actinomycetemcomitans (three strains) and Capnocytophaga spp. (three strains). All strains were sensitive to LL-37, and exhibited 99% effective dose of 7.5-to-11.6 ,g/ml. An amidated form of LL-37, pentamide-37, killed with about the same efficacy as LL-37. Partial inhibition of killing was noted at physiologic concentrations of NaCl, and complete inhibition was observed at 400 mM NaCl. At approximately the 99% effective dose , i.e., 10 ,g/ml , LL-37 also lost activity against A. actinomycetemcomitans in the presence of native or heat-inactivated 10,15% normal human AB serum. Pentamide-37 was less sensitive to serum inhibition than LL-37. In conclusion, certain oral, gram-negative bacteria are sensitive to the bactericidal activity of LL-37 at low concentrations of serum and salt, a condition likely to be found within the membrane-delimited phagolysosome. Modified forms of LL-37, such as pentamide-37, may be more suitable for future therapeutic application in the presence of serum. [source] Differential response of antioxidant compounds to salinity stress in salt-tolerant and salt-sensitive seedlings of foxtail millet (Setaria italica)PHYSIOLOGIA PLANTARUM, Issue 4 2000N. Sreenivasulu The modulation of antioxidant components was comparatively analysed in a salt-tolerant (cv. Prasad) and salt-sensitive (cv. Lepakshi) cultivar of foxtail millet (Setaria italica L.) under different NaCl concentrations. Under conditions of salt stress, the salt-tolerant cultivar exhibited increased total superoxide dismutase (SOD) and ascorbate peroxidase (APX) activity, whereas both enzyme activities decreased in acutely salt-stressed seedlings of the sensitive cultivar. At 200 mM NaCl, the tolerant foxtail millet cultivar responded with induction of cytosolic Cu/Zn-SOD and the Mn-SOD isoform at the protein level. The induced accumulation of the cytosolic Cu/Zn-SOD protein/activity is positively correlated with an elevated level of the cytosolic APX gene activity. The elevated cytosolic Cu/Zn-SOD and cytosolic APX activity correlates with an induced accumulation of their transcripts. Tolerant 5-day-old seedlings grown during high salinity treatment (200 mM NaCl) contained a lower amount of Na+ ions and showed a lower electrolyte leakage than sensitive seedlings. In conclusion, our comparative studies indicate that salt-induced oxidative tolerance is conferred by an enhanced compartment-specific activity of the antioxidant enzymes in response to compartment-specific signals. [source] Enhancement in the absorption of water and electrolytes from rat intestine by Hemidesmus indicus R. Br. root (water extract)PHYTOTHERAPY RESEARCH, Issue 7 2004D. A. Evans Abstract Hemidesmus indicus root in the form of suspension in water (10 mg/ml) containing 15.5 mM NaCl, 3 mM KCl and 12 mM glucose, when injected into the ligated jejunal sac (1 ml/sac) of rat, increased the absorption of water, Na+ and K+ (but not glucose) from the sac. This bioactivity was present in the water extract (5 or 10 mg/sac) of the root and not in the hexane extract. In contrast, the ethanol extract decreased the absorption of water and electrolytes from the jejunal sac. The effect of water extract was not affected by heat at 100 °C for 30 min. Intraperitoneal administration of the water extract (50 to 200 mg/kg) was devoid of any signi,cant effect on the jejunal absorption. Neither the root suspension nor the water extract (125,500 mg/kg) showed any signi,cant anti-ulcer and diuretic activities in rats. The intestinal motility was also not in,uenced by the root (water extract) when tested in mice. The present study indicates that H. indicus root powder or its water extract can be incorporated in oral rehydrating salt solution (ORS) for increasing its anti-diarrhoeal ef,cacy. Copyright © 2004 John Wiley & Sons, Ltd. [source] Differences in efficient metabolite management and nutrient metabolic regulation between wild and cultivated barley grown at high salinityPLANT BIOLOGY, Issue 4 2010Sabah Yousfi Abstract Physiological and biochemical responses of Hordeum maritimum and H. vulgare to salt stress were studied over a 60-h period. Growth at increasing salinity levels (0, 100, 200 and 300 mM NaCl) was assessed in hydroponic culture. H. maritimum was shown to be a true halophyte via its typical behaviour at high salinity. Shoot growth of cultivated barley was gradually reduced with increasing salinity, whereas that of wild barley was enhanced at 100 and 200 mm NaCl then slightly reduced at 300 mM NaCl. The higher salt tolerance of H. maritimum as compared to H. vulgare was due to its higher capacity to maintain cell turgor under severe salinity. Furthermore, H. maritimum exhibited fine regulation of Na+ transport from roots to shoots and, unlike H. vulgare, it accumulated less Na+ in shoots than in roots. In addition, H. maritimum can accumulate more Na+ than K+ in both roots and shoots without the appearance of toxicity symptoms, indicating that Na+ was well compartmentalized within cells and substituted K+ in osmotic adjustment. The higher degree of salt tolerance of H. maritimum is further demonstrated by its economic strategy: at moderate salt treatment (100 mm NaCl), it used inorganic solutes (such as Na+) for osmotic adjustment and kept organic solutes and a large part of the K+ for metabolic activities. Indeed, K+ use efficiency in H. maritimum was about twofold that in H. vulgare; the former started to use organic solutes as osmotica only at high salinity (200 and 300 mm NaCl). These results suggest that the differences in salt tolerance between H. maritimum and H. vulgare are partly due to (i) differences in control of Na+ transport from roots to shoots, and (ii) H. maritimum uses Na+ as an osmoticum instead of K+ and organic solutes. These factors are differently reflected in growth. [source] Developmental Changes in Effect of Cytokinin and Gibberellin on Shoot K+ and Na+ Accumulation in Salt-Treated Sorghum PlantsPLANT BIOLOGY, Issue 4 2001G. N. Amzallag Abstract: The effect of cytokinin (CK) and/or gibberellin (GA) treatments on shoot accumulation of Na+ and K+ was investigated in Sorghum bicolor exposed to 150 mM NaCl. These hormonal treatments modified the shoot content of Na+ and K+, but the effect varied throughout development. Comparison of ion concentration versus ion content in shoots indicates that regulation of shoot concentration of K+ is modified during a transition period of development. This change is concomitant with reorganization of the regulation network for meristem activity, an event also involving changes in sensitivity to CK and GA. This evidence suggests a strong interdependency between dynamic changes in a between-organ network of relations and control of accumulation of monovalent ions in the shoot. Moreover, a new pattern of regulation of shoot Na+ concentration emerges during the transition period. During this process GA appears progressively involved in regulation of Na retranslocation, while CK is rather controlling the root uptake of Na+. Accordingly, the spontaneous emergence of Na-includer and Na-excluder individuals observed from an initially homogeneous population is interpreted as related to variations in sensitivity to GA and CK during differentiation of this newly emerging pathway of regulation. [source] Silicon deposition in the root reduces sodium uptake in rice (Oryza sativa L.) seedlings by reducing bypass flowPLANT CELL & ENVIRONMENT, Issue 10 2006H. J. GONG ABSTRACT Sodium chloride reduces the growth of rice seedlings, which accumulate excessive concentrations of sodium and chloride ions in their leaves. In this paper, we describe how silicon decreases transpirational bypass flow and ion concentrations in the xylem sap in rice (Oryza sativa L.) seedlings growing under NaCl stress. Salt (50 mM NaCl) reduced the growth of shoots and roots: adding silicate (3 mM) to the saline culture solution improved the growth of the shoots, but not roots. The improvement of shoot growth in the presence of silicate was correlated with reduced sodium concentration in the shoot. The net transport rate of Na from the root to shoot (expressed per unit of root mass) was also decreased by added silicate. There was, however, no effect of silicate on the net transport of potassium. Furthermore, in salt-stressed plants, silicate did not decrease the transpiration, and even increased it in seedlings pre-treated with silicate for 7 d prior to salt treatment, indicating that the reduction of sodium uptake by silicate was not simply through a reduction in volume flow from root to shoot. Experiments using trisodium-8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS), an apoplastic tracer, showed that silicate dramatically decreased transpirational bypass flow in rice (from about 4.2 to 0.8%), while the apparent sodium concentration in the xylem, which was estimated indirectly from the flux data, decreased from 6.2 to 2.8 mM. Direct measurements of the concentration of sodium in xylem sap sampled using Philaenus spumarius confirmed that the apparent reduction was not a consequence of sodium recycling. X-ray microanalysis showed that silicon was deposited in the outer part of the root and in the endodermis, being more obvious in the latter than in the former. The results suggest that silicon deposition in the exodermis and endodermis reduced sodium uptake in rice (Oryza sativa L.) seedlings under NaCl stress through a reduction in apoplastic transport across the root. [source] Effects of salinity levels on proteome of Suaeda aegyptiaca leavesPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 8 2006Hossein Askari Abstract Saline soils are the major problem of cultivated lands of Iran. Suaeda aegyptiaca is a salt-tolerant plant (halophytes) that grow naturally in salt-affected areas of Iran. We have employed proteomics to identify the mechanisms of salt responsiveness in leaves of S.,aegyptiaca grown under different salt concentrations. Ten-day-old plants were treated with 0, 150, 300, 450, and 600,mM NaCl. After 30,days of treatment, leaf samples were collected and analyzed using 2-D-PAGE. Out of 700,protein spots reproducible detected within replications, 102,spots showed significant response to salt treatment compared to 0,mM,NaCl. We analyzed expression pattern of salt-responsive proteins using a hierarchical and two nonhierarchical (Fuzzy ART and SOM) statistical methods and concluded that Fuzzy ART is the superior method. Forty proteins of 12,different expression groups were analyzed using LC/MS/MS. Of these, 27,protein spots were identified including proteins involved in oxidative stress tolerance, glycinebetain synthesis, cytoskeleton remodeling, photosynthesis, ATP production, protein degradation, cyanide detoxification, and chaperone activities. The expression pattern of these proteins and their possible roles in the adaptation of S.,aegyptiaca to salinity is discussed. [source] Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of 4-sulfophenyl isothiocyanate-derivatized peptides on AnchorChipÔ sample supports using the sodium-tolerant matrix 2,4,6-trihydroxyacetophenone and diammonium citrateRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 6 2005Leon P. Oehlers The reagent 4-sulfophenyl isothiocyanate (SPITC) is an effective, stable, and inexpensive alternative to commercially available reagents used in the N-terminal sulfonation of peptides for enhanced postsource decay (PSD) in matrix-assisted laser desorption/ionization time-of-flight mass spectrometric (MALDI-TOFMS) analyses. However, suppression of ionization of sulfonated peptides due to sample and matrix contaminants such as sodium can be a problem when using prestructured MALDI target sample supports, such as the Bruker Daltonics AnchorChipÔ. We show that use of the salt-tolerant matrix 2,4,6-trihydroxyacetophenone containing diammonium citrate (THAP/DAC) as an alternative to , -cyanohydroxycinnamic acid (HCCA) reduces the need for extensive washing of ZipTip-bound peptides or additional on-target sample clean-up steps. Use of the THAP/DAC matrix results in selective ionization of sulfonated peptides with greater peptide coverage, as well as detection of higher mass derivatized peptides, than was observed for HCCA or THAP alone. The THAP/DAC matrix is quite tolerant of sodium contamination, with SPITC-peptides detectable in preparations containing up to 50,mM NaCl. In addition, THAP/DAC matrix was found to promote efficient PSD fragmentation of sulfonated peptides. We demonstrated the utility of using the THAP/DAC MALDI matrix for peptide sequencing with DNA polymerase , tryptic peptide mixture, as well as tryptic peptides derived from Xiphophorus maculatus brain extract proteins previously separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Copyright © 2005 John Wiley & Sons, Ltd. [source] Optical recordings of taste responses from fungiform papillae of mouse in situTHE JOURNAL OF PHYSIOLOGY, Issue 2 2001Yoshitaka Ohtubo 1Single taste buds in mouse fungiform papillae consist of ,50 elongated cells (TBCs), where fewer than three TBCs have synaptic contacts with taste nerves. We investigated whether the non-innervated TBCs were chemosensitive using a voltage-sensitive dye, tetramethylrhodamine methyl ester (TMRM), under in situ optical recording conditions. 2Prior to the optical recordings, we investigated the magnitude and polarity of receptor potentials under in situ whole-cell clamp conditions. In response to 10 mM HCl, several TBCs were depolarized by ,25 mV and elicited action potentials, while other TBCs were hyperpolarized by ,12 mV. The TBCs eliciting hyperpolarizing receptor potentials also generated action potentials on electrical stimulation. 3A mixture of 100 mM NaCl, 10 mM HCl and 500 mM sucrose depolarized six TBCs and hyperpolarized another three TBCs out of 13 identified TBCs in a taste bud viewed by optical section. In an optical section of another taste bud, 1 M NaCl depolarized five TBCs and hyperpolarized another two TBCs out of 11 identified TBCs. 4The number of chemosensitive TBCs was much larger than the number of innervated TBCs in a taste bud, indicating the existence of chemosensitivity in non-innervated TBCs. There was a tendency for TBCs eliciting the same polarity of receptor potential to occur together in taste buds. We discuss the role of non-innervated TBCs in taste information processing. [source] Salinity-induced changes in essential oil, pigments and salts accumulation in sweet basil (Ocimum basilicum) in relation to alterations of morphological developmentANNALS OF APPLIED BIOLOGY, Issue 2 2010N. Bernstein The objective of the project was to study salinity-induced effects on essential oil, pigments and salts accumulation in sweet basil (Ocimum basilicum, the cultivar Perrie) in relation to the alteration of plant morphological development and yield production. Hydroponically grown plants were exposed to one of six NaCl concentrations (1, 25, 50, 75, 100 and 130 mM NaCl). Inhibitory effects of salinity on biomass production of the shoot and the root, and area of individual leaves were apparent already under cultivation with 25 mM NaCl. Elevation of salinity from 1 to 100 mM NaCl induced 63% and 61% reductions in fresh and dry herb biomass production, respectively. The stress-induced reduction of foliage biomass sourced mainly from inhibition of leaf area development rather than reduction of internode and leaf number. Cl and Na concentrations in the leaves, stems and roots increased with elevation of NaCl concentration in the cultivation solution. While the extent of Cl accumulation was leaves>stems>roots, Na was largely excluded from the leaves and was preferentially accumulated in roots and the stems, potentially accounting for the moderate sensitivity of the leaf tissue to salinity. Salt stress increased the contents of essential oil and carotenoids in the leaves that may further account for the moderate sensitivity of sweet basil to salinity and suggest a potential for agro-industrial production. A twofold increase in both carotenoid concentration and the percent of essential oil in the fresh tissue was observed by elevation of the salinity from 1 to 130 mM NaCl. Overall, the stress induced increase of the percent of essential oil in the tissue in the salinity range 1,75 mM NaCl was about 50%, and thereby compensated for the similar reduction of biomass production in this salinity range, so that oil production on per plant basis was not reduced by salinity. [source] Comparative activity and stability under salinity conditions of different antimicrobial peptides isolated from aquatic animalsAQUACULTURE RESEARCH, Issue 16 2009Sara Emelie Löfgren Abstract This study reports the in vitro activity of six antimicrobial peptides (AMPs) produced by aquatic animals (most marine invertebrates): tachyplesin (Tach), magainin (Mag), clavanin (Clav), penaeidin (Pen), mytilin (Myt) and antilipopolysaccharide factor (ALF) against marine vibrios, filamentous fungi and yeast. Their stability under salinity conditions and seawater was also examined. The results showed that Mag, Myt and especially Tach and ALF (minimum inhibitory concentration<1.5 ,M) had a potent activity against all tested vibrio species, whereas Clav and Pen were ineffective (up to 50 ,M). With respect to the antifungal activity, each AMP had a different potency according to the fungal species. In general terms, Tach was the most potent peptide, followed by Mag. Interestingly, Tach, Myt and ALF had a significant effect on the filamentous fungus Fusarium solani that could be pathogenic to marine organisms. All AMPs had a tendency to decrease or lose their activity at high salinity (>225 mM NaCl). Tach and Myt were the most stable peptides, maintaining significant activity under seawater salinity (450 mM). Curiously, all peptides lost their effect under seawater conditions. The results suggest that Tach, ALF and Myt are the most promising candidates for potential therapeutic use in farmed-marine species, because all have a significant and broad antimicrobial activity maintained at high salinity. [source] Crystallization and preliminary X-ray crystallographic analysis of highly thermostable L2 lipase from the newly isolated Bacillus sp.ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 6 2010Purified thermostable recombinant L2 lipase from Bacillus sp. L2 was crystallized by the counter-diffusion method using 20% PEG 6000, 50,mM MES pH 6.5 and 50,mM NaCl as precipitant. X-ray diffraction data were collected to 2.7,Å resolution using an in-house Bruker X8 PROTEUM single-crystal diffractometer system. The crystal belonged to the primitive orthorhombic space group P212121, with unit-cell parameters a = 87.44, b = 94.90, c = 126.46,Å. The asymmetric unit contained one single molecule of protein, with a Matthews coefficient (VM) of 2.85,Å3,Da,1 and a solvent content of 57%. [source] Chromatin dynamics of unfolding and refolding controlled by the nucleosome repeat length and the linker and core histonesBIOPOLYMERS, Issue 4 2007Toshiro Kobori Abstract Chromatin is composed of genomic DNA and histones, forming a hierarchical architecture in the nucleus. The chromatin hierarchy is common among eukaryotes despite different intrinsic properties of the genome. To investigate an effect of the differences in genome organization, chromatin unfolding processes were comparatively analyzed using Schizosaccaromyces pombe, Saccharomyces cerevisiae, and chicken erythrocyte. NaCl titration showed dynamic changes of the chromatin. 400,1000 mM NaCl facilitated beads with ,115 nm in diameter in S. pombe chromatin. A similar transition was also observed in S. cerevisiae chromatin. This process did not involve core histone dissociation from the chromatin, and the persistence length after the transition was ,26 nm for S. pombe and ,28 nm for S. cerevisiae, indicating a salt-induced unfolding to "beads-on-a-string" fibers. Reduced salt concentration recovered the original structure, suggesting that electrostatic interaction would regulate this discrete folding-unfolding process. On the other hand, the linker histone was extracted from chicken chromatin at 400 mM NaCl, and AFM observed the "beads-on-a-string" fibers around a nucleus. Unlike yeast chromatin, therefore, this unfolding was irreversible because of linker histone dissociation. These results indicate that the chromatin unfolding and refolding depend on the presence and absence of the linker histone, and the length of the linker DNA. © 2007 Wiley Periodicals, Inc. Biopolymers 85:295,307, 2007. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] The chromatography-free release, isolation and purification of recombinant peptide for fibril self-assemblyBIOTECHNOLOGY & BIOENGINEERING, Issue 5 2009B.M. Hartmann Abstract One of the major expenses associated with recombinant peptide production is the use of chromatography in the isolation and purification stages of a bioprocess. Here we report a chromatography-free isolation and purification process for recombinant peptide expressed in Escherichia coli (E. coli). Initial peptide release is by homogenization and then by enzymatic cleavage of the peptide-containing fusion protein, directly in the E. coli homogenate. Release is followed by selective solvent precipitation (SSP) to isolate and purify the peptide away from larger cell contaminants. Specifically, we expressed in E. coli the self-assembling ,-sheet forming peptide P11 -2 in fusion to thioredoxin. Homogenate was heat treated (55°C, 15,min) and then incubated with tobacco etch virus protease (TEVp) to release P11 -2 having a native N-terminus. SSP with ethanol at room temperature then removed contaminating proteins in an integrated isolation-purification step; it proved necessary to add 250,mM NaCl to homogenate to prevent P11 -2 from partitioning to the precipitate. This process structure gave recombinant P11 -2 peptide at 97% polypeptide purity and 40% overall yield, without a single chromatography step. Following buffer-exchange of the 97% pure product by bind-elute chromatography into defined chemical conditions, the resulting peptide was shown to be functionally active and able to form self-assembled fibrils. To the best of our knowledge, this manuscript reports the first published process for chromatography-free recombinant peptide release, isolation and purification. The process proved able to deliver functional recombinant peptide at high purity and potentially low cost, opening cost-sensitive materials applications for peptide-based materials. Biotechnol. Bioeng. 2009; 104: 973,985. © 2009 Wiley Periodicals, Inc. [source] A novel purification strategy for retrovirus gene therapy vectors using heparin affinity chromatographyBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2005María de las Mercedes Segura Abstract Membrane separation and chromatographic technologies are regarded as an attractive alternative to conventional academic small-scale ultracentrifugation procedures used for retrovirus purification. However, despite the increasing demands for purified retroviral vector preparations, new chromatography adsorbents with high specificity for the virus have not been reported. Heparin affinity chromatography is presented here as a novel convenient tool for retrovirus purification. The ability of bioactive retroviral particles to specifically bind to heparin ligands immobilized on a chromatographic gel is shown. A purification factor of 63 with a recovery of 61% of functional retroparticles was achieved using this single step. Tentacle heparin affinity supports captured retroviral particles more efficiently than conventional heparin affinity chromatography supports with which a lower recovery was obtained (18%). Intact, infective retroviral particles were recovered by elution with low salt concentrations (350 mM NaCl). Mild conditions for retrovirus elution from chromatographic columns are required to preserve virus infectivity. VSV-G pseudotyped retroviruses have shown to be very sensitive to high ionic strength, losing 50% of their activity and showing membrane damage after a short exposure to 1M NaCl. We also report a complete scaleable downstream processing scheme for the purification of MoMLV-derived vectors that involves sequential microfiltration and ultra/diafiltration steps for virus clarification and concentration respectively, followed by fractionation by heparin affinity chromatography and final polishing by size-exclusion chromatography. Overall, by using this strategy, a 38% yield of infective particles can be achieved with a final purification factor of 2,000. © 2005 Wiley Periodicals, Inc. [source] Purification, crystallization and preliminary structural analysis of nucleoside diphosphate kinase from Bacillus anthracisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 12 2007Gauri Misra Bacillus anthracis nucleoside diphosphate kinase (BaNdk) is an enzyme whose primary function is to maintain deoxynucleotide triphosphate (dNTP) pools by converting deoxynucleotide diphosphates to triphosphates using ATP as the major phosphate donor. Although the structures of Ndks from a variety of organisms have been elucidated, the enzyme from sporulating bacteria has not been structurally characterized to date. Crystals of the B. anthracis enzyme were grown using the vapour-diffusion method from a hanging drop consisting of 2,µl 10,mg,ml,1 protein in 50,mM Tris,HCl pH 8.0, 50,mM NaCl, 5,mM EDTA equilibrated against 500,µl reservoir solution consisting of 2.25,M ammonium formate and 0.1,M HEPES buffer pH 7.25. Diffraction data extending to 2.0,Å were collected at room temperature from a single crystal with unit-cell parameters a = b = 107.53, c = 52.3,Å. The crystals are hexagonal in shape and belong to space group P6322. The crystals contain a monomer in the asymmetric unit, which corresponds to a Matthews coefficient (VM) of 2.1,Å3,Da,1 and a solvent content of about 36.9%. [source] The quaternary structure of the amidase from Geobacillus pallidus RAPc8 is revealed by its crystal packingACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 12 2006Vinod B. Agarkar The amidase from Geobacillus pallidus RAPc8, a moderate thermophile, is a member of the nitrilase enzyme superfamily. It converts amides to the corresponding acids and ammonia and has application as an industrial catalyst. RAPc8 amidase has been cloned and functionally expressed in Escherichia coli and has been purified by heat treatment and a number of chromatographic steps. The enzyme was crystallized using the hanging-drop vapour-diffusion method. Crystals produced in the presence of 1.2,M sodium citrate, 400,mM NaCl, 100,mM sodium acetate pH 5.6 were selected for X-ray diffraction studies. A data set having acceptable statistics to 1.96,Å resolution was collected under cryoconditions using an in-house X-ray source. The space group was determined to be primitive cubic P4232, with unit-cell parameter a = 130.49 (±0.05) Å. The structure was solved by molecular replacement using the backbone of the hypothetical protein PH0642 from Pyrococcus horikoshii (PDB code 1j31) with all non-identical side chains substituted with alanine as a probe. There is one subunit per asymmetric unit. The subunits are packed as trimers of dimers with D3 point-group symmetry around the threefold axis in such a way that the dimer interface seen in the homologues is preserved. [source] | |||||||||||||||||||