Moreover, we find that the screen effect also highly depends on t

Moreover, we find that the screen effect also highly depends on the length of nanowires on the field emission performance. The turn-on fields increase from 6.6 to 13.6 V μm−1, and β values LOXO-101 mouse decrease from 1,857 to 699 after the 10-h growth. The screen effect is predominated after the length of nanowires increases, namely the longer growth time, thereby degrading the field emission performance. Consequently, the turn-on fields and β values change from 13.6 V μm−1 and 699 to 6.6 V μm−1 and 1,857, respectively, as the growth time of Sn-doped ITO NWs decreases into 3 h. The detailed screen effect in terms of electrical potential and NW density was investigated

in details. The findings provide an effective way

of improving the field emission properties for nano-emitter application. Acknowledgment This work was supported by the National Science Council, Taiwan, under grant number NSC-99-2221-E-007-069-MY3. References 1. Ngamsinlapasathian S, Sreethawong T, Suzuki Y, Yoshikawa S: Doubled layered ITO/SnO learn more 2 conducting glass for substrate of dye-sensitized solar cells. Sol Energy Mater Sol Cells 2006, 90:2129– CrossRef 2. Kamei M, Yagami T, Takaki S, Shigesato Y: Heteroepitaxial growth of tin-doped indium oxide films on single crystalline yttria stabilized zirconia substrates. Appl Phys Lett 1994, 64:2712–2714.CrossRef 3. Ohta H, Orita M, Hirano M, Tanji H, Kawazoe H, Hosono H: Highly electrically conductive indium–tin–oxide thin films epitaxially grown on yttria-stabilized zirconia (100) by pulsed-laser Lepirudin deposition. Appl Phys Lett 2000, 76:2740.CrossRef 4. O’Dwyer C, Szachowicz M, Visimberga G, Lavayen V, Newcomb S, Torres C: Bottom-up growth of fully transparent contact layers of indium tin oxide nanowires for light-emitting devices. Nat Nanotechnol 2009, 4:239–244.CrossRef 5. Gao J, Chen R, Li DH, Jiang L, Ye JC, Ma XC, Chen XD, Xiong QH, Sun HD, Wu T: UV light emitting transparent conducting tin-doped indium oxide (ITO) nanowires. Nanotechnol

2011, 22:195706.CrossRef 6. Wan Q, Feng P, Wang TH: Vertically aligned tin-doped indium oxide nanowire arrays: epitaxial growth and electron field emission properties. Appl Phys Lett 2006, 89:123102.CrossRef 7. Wan Q, Dattoli E, Fung W, Guo W, Chen Y, Pan X, Lu W: High-performance transparent conducting oxide nanowires. Nano Lett 2006, 6:2909–2915.CrossRef 8. Peng XS, Meng GW, Wang XF, Wang YW, Zhang J, Liu X, Zhang LD: Synthesis of oxygen-deficient indium-tin-oxide (ITO) nanofibers. Chem Mater 2002, 14:4490–4493.CrossRef 9. Lee SY, Lee CY, Lin P, Tseng TY: Low temperature synthesized Sn doped indium oxide nanowires. Nanotechnol 2005, 16:451–457.CrossRef 10. Orlandi MO, Aguiar R, Lanfredi AJC, Longo E, Varela JA, Leite ER: Tin-doped indium oxide nanobelts grown by carbothermal reduction method. Appl Phys A: Mater Sci Process 2005, 80:23–25.CrossRef 11.

The oxygen permeability was measured in a HMI module (with a mucu

The oxygen permeability was measured in a HMI module (with a mucus layer of 200 μm) maintaining a completely

anaerobic upper chamber (water previously gassed with 95% N2-5% CO2) and an aerobic lower chamber (liquid constantly gassed with an air pump). Measurements were carried out at 37°C by following the increasing oxygen concentration in the upper chamber by means of a luminescent LDO oxygen probe (Hach Lange, Mechelen, Belgium) placed on the outlet connection of the luminal side of the module. Data of the increasing oxygen concentration in the upper chamber, collected in the first 30 minutes, were used to calculate the relative permeability (PmO2) using the following equation, as shown by Autophagy inhibitor cost Saldena et al. [40]: where MO2 is the mass of oxygen transferred in the time t; (cO2)A and (cO2)B are the concentrations of oxygen in the upper and lower chamber of the HMI module with a mucus layer with a surface S and a thickness x. The quotient DO2/x corresponds to the oxygen permeability (PmO2). Characterization of the biological parameters Lactobacillus rhamnosus GG (LMG 18243, BCCM/LMG, Ghent, Belgium) was used as a positive control to assess the capacity of bacteria to colonize

the double functional layer [55]. LGG was grown in MRS medium, quantified by plate count (LGG t0). The fully grown OICR-9429 liquid culture was then circulated through the upper chamber of an HMI module at a flow correspondent to a shear stress of 3 dynes cm−2 (6.5 mL min−1). After 1.5 h, the simulation was Temsirolimus stopped Cytidine deaminase and the luminal suspension removed. The functional layer was rinsed twice with phosphate buffer solution to remove the non-adhered bacteria. Subsequently, the luminal side of the functional layer was rinsed with Triton X-100 to remove the adhering bacteria. The obtained bacterial suspension was analyzed for microbial concentration measurements using the plate count technique on MRS (LGG t1.5). Percent of adhering bacteria was calculated

as LGG t1.5/LGG t0. In a second set of experiments, it was evaluated the capacity of Caco-2 cells to survive in the HMI module in presence of a complex microbial community (derived from a SHIME reactor). An HMI module was set up as described in the first paragraph of the Methods section and the complex microbial community was introduced in the upper chamber of the HMI module. In a parallel experiment, the enterocytes were directly exposed to the same microbiota (i.e. viability after direct contact) in a microtiter plate. The cell viability in the 2 setups was compared by means of the MTT ((3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) colorimetric test [56] after 48 h of incubation in the HMI module and after 2 h of direct contact.

Endley S, McMurray D, Ficht TA: Interruption of the cydB locus in

Endley S, McMurray D, Ficht TA: Interruption of the cydB locus in Brucella abortus attenuates intracellular survival and virulence in

the mouse model of infection. J Bacteriol 2001, 183:2454–62.CrossRefPubMed 36. Cotter PA, Chepuri V, Gennis RB, Gunsalus RP: Cytochrome-O learn more ( cyoABCDE ) and D ( cydAB ) oxidase gene-expression in Escherichia coli is regulated by oxygen, pH, and the fnr gene-product. Journal of selleck chemical Bacteriology 1990, 172:6333–6338.PubMed 37. Watson RJ, Chan YK, Wheatcroft R, Yang AF, Han SH:Rhizobium meliloti genes required for C-4-dicarboxylate transport and symbiotic nitrogen-fixation are located on a megaplasmid. Journal of Bacteriology 1988, 170:927–934.PubMed 38. Yurgel S, Mortimer MW, Rogers KN, Kahn ML: New substrates for the dicarboxylate transport system of Sinorhizobium meliloti. Journal of Bacteriology 2000, 182:4216–4221.CrossRefPubMed 39. Dubin DT, Rosenthal SM: The acetylation of polyamines in Escherichia coli. J Biol Chem 1960, 235:776–782.PubMed 40. Munro GF, Hercules K, Morgan J, Sauerbier W: Dependence of the putrescine content of Escherichia coli on the osmotic strength of the medium. J Biol Chem 1972, 247:1272–1280.PubMed 41. Yamamoto S, Yamasaki K, Takashina K, Katsu T, Shinoda S: Characterization of putrescine production in nongrowing

APO866 solubility dmso Vibrio parahaemolyticus cells in response to external osmolality. Microbiol Immunol 1989, 33:11–21.PubMed 42. Chao TC, Becker A, Buhrmester J, Pühler A, Weidner S: The Sinorhizobium meliloti fur gene regulates, with dependence on Mn(II), transcription of the sitABCD operon, encoding a metal-type transporter. Journal of Bacteriology 2004, 186:3609–3620.CrossRefPubMed 43. Platero RA, Jaureguy M, Battistoni FJ, Fabiano ER: Mutations in sitB and sitD genes affect manganese-growth requirements in Sinorhizobium meliloti. Fems Microbiology Letters 2003, 218:65–70.CrossRefPubMed 44. Bardin S, Regorafenib molecular weight Dan S, Osteras M, Finan TM: A phosphate transport system is required for symbiotic nitrogen fixation by Rhizobium meliloti. Journal of Bacteriology

1996, 178:4540–4547.PubMed 45. Suziedeliene E, Suziedelis K, Garbenciute V, Normark S: The acid-inducible asr gene in Escherichia coli : Transcriptional control by the phoBR operon. Journal of Bacteriology 1999, 181:2084–2093.PubMed 46. Iyoda S, Kamidoi T, Hirose K, Kutsukake K, Watanabe H: A flagellar gene fliZ regulates the expression of invasion genes and virulence phenotype in Salmonella enterica serovar Typhimurium. Microbial Pathogenesis 2001, 30:81–90.CrossRefPubMed 47. Olson ER, Dunyak DS, Jurss LM, Poorman RA: Identification and characterization of dppa , an Escherichia coli gene encoding a periplasmic dipeptide transport protein. Journal of Bacteriology 1991, 173:234–244.PubMed 48. Barloy-Hubler F, Cheron A, Hellegouarch A, Galibert F: Smc01944, a secreted peroxidase induced by oxidative stresses in Sinorhizobium meliloti 1021. Microbiology 2004, 150:657–64.CrossRefPubMed 49.

The FTIR spectrum will therefore, exhibit peak for Al-OH and not

The FTIR spectrum will therefore, exhibit peak for Al-OH and not due to loss of hydroxyl group (Figure 7). The OH group may be lost if Al(OH)3 is heated in open according to Figure 7 FTIR spectra. I: loaded particles (a); particles loaded with 10.0% (b), 100.0% (c) and 432.4% (d) monomolecular layer of phenanthrene. II: spectra obtained by subtraction of spectrum a from b, c and d, resulting in e, f and g, respectively. The band near 950 cm-1 is related to the surface characteristics of alumina nanoparticles [167]. The absorbance of phenanthrene can be distinguished in both spectra,

f and g [146]. Pure Al2O3 may exhibit a peak due to Al-O. This assignment, on find more the basis of IR spectral data, may not be true. The authors [146] claim that dimethyl sulphoxide (DMSO) used in their experiment is selleck chemical a

hydroxyl radical scavenger, and in aqueous medium, it removes the OH radical as shown below [168, 169]: The last equation is wrong in the above reactions. It should produce CH3OH not CH2OH. Generally, free radicals combine with another species to give a molecule. The effect of two fluorescent nanoparticles, fluorescein isothiocyanate (FITC)-silica nanoparticles and quantum dots (QD), on germination of rice seeds has been studied [170]. In addition, the uptake capacity of photostable CdSe QD and FITC-labelled silica nanoparticles (SNP) has also been studied. It was observed that germination in the presence of FITC-labelled SNP was Mannose-binding protein-associated serine protease enhanced while it was arrested with QD. Since the QD contain Cd as one of the known toxic metal ions, it may have reversibly

acted on germination of rice seeds. However, transport of both fluorescent nanoparticles has been observed in rice seedlings. The FITC-SNP appears to be useful to plants and has shown good fluorescence in rice seedlings. It is therefore suggested that it may be used for bioimaging in plant tissues because of the photostability of SNP. Bioimaging can be done only with the help of fluorescent materials especially in vivo. Since very limited study has been done in this direction [171], the exact nature and mechanism of transport of nanoparticles is not well understood. It can equally be used in mammals, but the toxicity of such nanoparticles in biological system must be checked prior to its use. Conflicting reports have been received about the toxicity of QD [172, 173] in mammals even though CdSe QD is known to arrest the root growth of rice seedlings. The useful application of metal or/and metal oxide nanoparticles is still a matter of controversy. In some cases, it has been found to be useful, while in many other instances, it appears to be phytotoxic [9–13]. The ZnO nanoparticles in this context have been used as growth promoter for Cicer arietinum and Vigna radiata seedlings [174]. They were monodispersed and their spherical shape was confirmed by SAED pattern (Figure 8). It was observed that in the case of V.

Therefore, the small amount of longitudinal stress along the carb

Therefore, the small amount of longitudinal stress along the carbon nanowire can be explained by the fact that most of the dimensional changes occur in the polymer phase and only small dimensional

changes occur during the solid carbon formation itself. It also should be stressed that the slow temperature ramp rate of 1°C/min during the pyrolysis process and the slow cooling process afterwards would tend to anneal out any excessive stresses accumulated in the carbon structure. The shape of the supporting posts was converted from a brick shape to a four-pole tent shape and the wire bent downwards at supports where the nanowire and the post are connected as shown in the inset image of Figure 2b and Additional file 1: Figure S2. This geometric shape is a result of the very good adhesion of SU-8 to the substrate, where the bottom part of the posts, during pyrolysis, is held strongly by the substrate while Eltanexor datasheet the top of the posts tend to shrink freely inwards and downwards. As a result of this type of non-uniform volume reduction of the posts, the side-wall profile of the posts changes from a straight wall to a curved one and as a consequence the suspended nanowires experience more elongation at the top compared to the bottom and the nanowire supports are bent downwards. It is this difference

in the top to bottom elongation across the nanowire thickness that causes the transverse stress gradient in the nanowire. The photoresist wires are formed thicker at the supports as shown in the dashed rectangle of Figure 2a because the photomask open area in the 2nd UV lithography Bafilomycin A1 supplier process is enlarged abruptly at the supports such that the UV energy is transferred deeper at the ends of the nanowire. The polymer supports remain thicker

compared to the wire through pyrolysis and transforms into thick carbon bent supports. This bridge-shaped carbon nanowire geometry and the tensional stress, that is not significant but grows triclocarban along the nanowire thickness, enhanced the structural robustness of the nanowire and could enable high aspect ratio (approximately 450) suspended carbon nanowires to resist stiction to the substrate even when they were wet processed with very small gaps between the nanowires and the substrate. Figure 2 SEM images of suspended SU-8 microwire structure, a corresponding carbon nanowire structure, and suspended carbon nanomesh. (a) A suspended SU-8 microwire structure before pyrolysis and (b) a corresponding suspended carbon nanowire structure after pyrolysis. (c) A suspended carbon nanomesh. Inset images of (a) and (b) are the enlarged views of the polymer and carbon supports. In contrast to suspended carbon nanowires fabricated using electrospinning, the UV lithography-patterned suspended carbon nanowires can be shaped in a wide GS-7977 concentration variety of geometries such as nanomeshes.

The other

The other selleckchem five bacterial species represent previously unreported associations

for R. microplus. Whereas C. glutamicum and S. marcescens were detected in eggs only, S. sciuri was present in male and female ticks, F. magna in eggs and female ticks, and S. dysgalactiae in eggs, male ticks, and female ticks. Because of our permissive approach to assess bacterial diversity, e.g., the ticks used in this study were not disinfected prior to DNA extraction, the prevalence of these new bacterial associations with R. microplus needs to be confirmed. However, it is relevant to note that S. dysgalactiae and S. marcescens are known to cause bovine mastitis, whereas F. magna was detected in papillomatous digital dermatitis lesions of cattle [27–29]. Epigenetics inhibitor Staphylococcus

sciuris is commonly found in the skin of cattle and other animals, while the natural habitats of C. glutamicum include soil, soils contaminated with bird feces, sewage and manure, and vegetables and fruits [30, 31]. In their natural environment, R. microplus eggs may be exposed to C. glutamicum after oviposition by gravid female ticks. Clustering analysis showed that the microbial biota detected in the ovary tissue of adult female ticks was the most dissimilar tissue of all the tick samples tested (Figure 1). Additionally, the least diverse microbial biota was detected in this tissue. Members of the Coxiellaceae family were the most prevalent bacteria in cattle tick ovary. Consistent with this finding, the Coxiellaceae were also found in the egg and adult female samples (Figure 1). Relative abundance of bacterial genera by tick life stage and tissue sample One hundred twenty-one bacterial Adenosine genera were detected in all the life stages and tissues sampled in this study (see Additional File 1 Table S1). Among the genera found in our study, Arthrobacter, Bacillus, Curtobacterium,

Enterobacter, Microbacterium, Paenibacillus, Pantoea, Pseudomonas, Rhodococcus, Serratia, Staphylococcus, and Stenotrophomonas are genera previously reported to be harbored by R. microplus isolated from ticks collected in Australia [24]. Enterobacter, Pseudomonas, and Staphylococcus, found in both our study and the Australian study, were also SHP099 supplier cultured from homogenates of R. microplus in Bangladesh that were produced following surface sterilization and dissections using sterile technique [32]. Infection with Achromobacter and Escherichia was previously reported for cattle ticks from the Bangladesh study but not the Australian study. Among the life stages sampled, the total number of bacterial genera detected in the egg, adult male, and adult female ticks was 54, 53, and 61, respectively (Additional File 1 Table S1). Of those numbers, 25, 25, and 27 genera were unique to the egg, adult male, and adult female life stages, respectively.


genetic basis for the aberrant immune response in sus


genetic basis for the aberrant immune response in susceptible individuals is not clearly defined. Several years ago we discovered that inbred strains of mice vary over 4 logs in their susceptibility to infection with C. immitis and that resistance is the dominant phenotype [10]. This proved to be a selleckchem polygenic trait, and a resistance locus was identified on chromosome 6 using recombinant inbred BXD lines [11]. C57BL/6 mice are more sensitive to infection with C. immitis than DBA/2 mice such that nearly all C57BL/6 mice die between day 16 and 18 post-infection [10]. We have shown that infected C57BL/6 mice make more IL-10 and IL-4 and less interferon gamma (IFN-γ) in their lungs compared to DBA/2 mice [12]. IL-10 has pleiotropic effects on Selleckchem GW-572016 different cell types that affect the acquired immune response

resulting in inhibition of the development of Th1 immune responses [13]. In the current work, microarray analysis was used to identify genes differentially expressed between lung tissue samples from resistant DBA/2 and sensitive C57BL/6 mice following infection with C. immitis. Differentially expressed genes were mapped onto biological pathways, gene ontologies and protein networks in order to fully characterize the biological processes PF-3084014 that contribute to a protective response against C. immitis infection. Results C. immitis infection in DBA/2 resistant versus sensitive C57BL/6 mice The colony forming units (CFUs) in the right (R) lung and spleen of DBA/2 and C57BL/6 mice were determined after intra-nasal (i.n.) infection with C. immitis arthroconidia. We chose three time points after infection Selleckchem Sirolimus for analysis

(day 10, 14 and 16). Since mice were only infected with 50 CFU and not all of them were inhaled, day 10 is the earliest day when there are enough organisms in the lungs to reliably quantitate pulmonary infection in all mice. C57BL/6 mice began to die on day 16 so this was selected as the last time point, and day 14 was chosen as an intermediate time point. On day 10 after infection there were equal numbers of CFU in the lungs of both strains of mice and we could not detect dissemination by culturing their spleens (Figure 1). On day 14 and 16 post-infection DBA/2 mice had 10 to 100 fold fewer CFU/lung, and in this experiment no DBA/2 mice had detectable dissemination to the spleen, whereas all the C57BL/6 mice had positive spleen cultures. Figure 1 Comparison of C. immitis infection between resistant DBA/2 and sensitive C57BL/6 mice. Mice were infected (i.n.) and then sacrificed at the indicated intervals. The right lung and spleen of each mouse was homogenized and cultured quantitatively. Each symbol represents an individual mouse and the horizontal lines are the geometric mean ± standard error of the mean.

Curr Pharm Des 12:4601–4611PubMedCrossRef”
“Introduction Rea

Curr Pharm Des 12:4601–4611PubMedCrossRef”
“Introduction Reactive oxygen species (ROS) such as O2 −, H2O2 and •OH are generated in cells through aerobic metabolic processes or as a result of interaction with exogenous agents. Low levels are essential for proper cell function, but excess

levels of ROS are responsible for ‘oxidative stress’ which has been linked with the progression of ageing and many human diseases, e.g. neurogenerative, cardiovascular and cancer. Superoxide dismutases (SODs), catalase (CAT) and glutathione peroxidase (GPx) are enzymes which act as a primary cellular defence system against oxidative damage in living organisms. Copper(II) has an important biological role in all living systems as an essential trace element (Linder and Hazegh-Azam, 1996). The Cu(II) complexes with organic ligands have been used as analgesic, antipyretic, antiinflammatory and a platelet anti-aggregating agents. Due to the redox behaviour of the Cu(II)/Cu(I) system and the interaction of copper complexes with O2 biomimetic complexes

of copper ions with biologically interesting ligand have been investigated in detail. They have antioxidant, antitumor activity and protect against some injuries being consequences of UV exposure (Zheng et al., 2006). Recently, several reports have appeared in the literature describing RG7112 molecular weight the anticancer activity of Cu(II) derivatives of many classes of Selleck Vistusertib nitrogen donors including thiosemicarbazone, imidazole (Huang et al., 2005). Among them, pyrazole-containing complexes have been reported to possess antitumor activity which is comparable to that of cisplatin (Sakai et al., 2000; Wheate et

al., 2001; Al-Allaf and Rashan, 2001). In addition, considerable interest in the pyrazole moiety has been stimulated by promising pharmacological, agrochemical and analytical applications of pyrazole-containing derivatives (Eicher and Hauptmann, 1995; Eliguero et al., Methane monooxygenase 1997; Onoa et al., 1999, 2002; Duivenvoorden et al., 2005). Recently, substituted pyrazoles have been used as analytical reagents in the complexation of transition metal ions (Wisniewski et al., 1994; Majsterek et al., 2011). In our previous articles, we have investigated the synthesis, X-ray structures, physicochemical properties and preliminary cytotoxic effect for Cu(II) complexes with pyrazole derivatives as ligands (Miernicka et al., 2008; Budzisz et al., 2009, 2010). Here, we present evaluation of the antioxidant activity of six Cu(II) complexes with three ligands: 5-substituted-3-methyl/phenyl-1-(2-pyridinyl)-1H-pyrazol-4-carboxylic acid methyl ester (1a) or phosphonic acid dimethyl ester (1b) and 1-benzothiazol-2-yl-5-(2-hydroxyphenyl)-3-methyl-1H-pyrazole-4-carboxylic acid methyl ester (1c). We assessed the ability to act these complexes as SOD, CAT and GPx enzyme mimics and to scavenge ROS.

Sensitivity analyses with stratification for nutritional status s

Sensitivity analyses with stratification for nutritional status showed that the cost-effectiveness for weight as outcome

was especially high in malnourished patients but also (Epacadostat concentration though slightly less high) in well-nourished patients. If selleck kinase inhibitor the nutritional intervention would be targeted to elderly patients (≥75 years), the probability that the intervention was cost-effective was also high. This was in marked contrast with younger patients (55–74 years), where cost effectiveness was <50%, possibly due to the fact that younger patients generally have a better general condition than elderly patients, so that nutritional intervention will have less effect on their weight. With respect to QALY, the probability for the intervention to be cost-effective was relatively low for the total population and subgroups; however, the probability that the nutritional intervention was cost-effective with respect to QALY was highest (60–90% depending on willingness to pay) in younger patients (55–74 years). Our results confirm previous studies indicating that the costs of nutritional intervention are extremely low (in our case, less than 3%) compared with regular health care costs such as hospital

costs [20, 22–24, 43, 44]. Previous research in malnourished patients living in the community and in a heterogeneous group of malnourished patients admitted to a mixed medical and surgical ward indicated that nutritional intervention with oral nutritional Emricasan ic50 supplementation alone or combined with dietetic counseling was cost-effective with regard to length PRKD3 of stay [24]. We found that, in hip fracture patients, the probability of the nutritional intervention to be cost-effective with regard to QALY as outcome was relatively low in the older age group of ≥75 years. Of note, older patients more often live in nursing homes even before the fracture, and

they tend to have more co-morbidities for which medical treatment is needed; both these factors may overrule the potential cost-reduction induced by the nutritional intervention. Also, after hip fracture, older and malnourished patients may have more postoperative complications and hospital re-admissions as compared with younger and well-nourished patients. As also noted in the literature, medical costs do not seem to be associated with the type of surgical procedure but are mainly determined by increasing age, living in an institution and the presence of co morbidity [21, 38, 41]. Finally, home-dwelling older patients often live alone, which may also result in a higher requirement of professional care as compared with patients living with their partner.

pylori orientation [24] In contrast, bicarbonate and not CO2 app

In contrast, bicarbonate and not CO2 appears to be the Foretinib manufacturer inducer of expression of the B. anthracis toxins [25]. Using the P ebpA ::lacZ PF-6463922 research buy fusion in OG1RF, we first investigated the independent effect of CO2 and NaHCO3 on ebpA in buffered TSBG with or without the presence of 0.1 M NaHCO3 and/or 5% CO2. pH was controlled during the experiment and remained at pH 7.5 ± 0.25. As shown in Fig. 7, ebpA expression in TSBG-air did not differ appreciably from that in TSBG- 5% CO2, reaching

a peak of expression early in stationary phase (15.8 and 14.5 β-gal units, respectively); expression then decreased to 2 and 0.4 β-gal units, respectively, at 24 hr. In the presence of NaHCO3, ebpA expression peak was ~4-fold higher with 46.5 β-gal units for the NaHCO3-air culture at entry into stationary phase (5 hr) compared to 9.8 β-gal when the cells were grown without NaHCO3, and 46.0 β-gal units for the selleck screening library 5% CO2 plus NaHCO3 culture compared to 12.5 β-gal when grown in presence of CO2 only. The bicarbonate effect persisted late into stationary

phase with 42.5 and 40.7 β-gal units when grown in air-NaHCO3 and CO2-NaHCO3 respectively. A similar profile with increased ebpR expression in the presence of bicarbonate but not in presence of CO2 was also observed (data not shown). Furthermore, the differential effect of CO2 and NaHCO3 was also detected in BHI or when potassium bicarbonate was used as a source for HCO3 – (data not shown). Taken together, these results demonstrate that the increase in ebpR and ebpA expression is caused by the addition of HCO3 – and not CO2. Figure 7 ebpA expression affected by NaHCO 3 , and not CO 2 . For β-gal assays, samples were collected every hour from 3 to 8 hr, then at 10 and 24 hr after starting the culture (x axis). Growth

curves of OG1RF containing P ebpA ::lacZ are shown in air with a thin gray line, in NaHCO3/air with thin orange line, in CO2 with a dense gray line, and in NaHCO3/CO2 with a dense orange line. The Aprepitant β-gal assays for OG1RF containing P ebpA ::lacZ are represented with closed black square, closed orange square, open black square, and open orange square when the cells were grown in air, 5% CO2, NaHCO3-air, and NaHCO3-5% CO2, respectively. All sets of cultures presented were analyzed concurrently. This figure is a representative of at least two experiments. A. OD600 nm readings. B. β-gal assays (β-gal units = OD420 nm/protein concentration in mg/ml). Since NaHCO3 is in equilibrium with H2CO3, HCO3-, and CO3 2- depending of the pH, temperature and partial pressure of CO2, we next tested a possible pH effect on ebpA expression when cells were grown in buffered TSBG. In a preliminary experiment, OG1RF (P ebpA ::lacZ) was grown in buffered TSBG with pH ranging from 5 to 9. Severe growth inhibition was observed at pH 5 and 9 with mild growth inhibition at pH 6, compared to unaffected growth at pH 7 and 8 (data not shown).