[30] for Si nanoparticles synthesized by pulsed laser ablation, where the determined crystallization temperatures were in the

range of 800 to 1,300 K (depending on the nanoparticle Cilengitide nmr size). These temperatures are far below the melting point of bulk Si (1,683 K). In our case, the annealing temperature of 1,373 K is also well below the melting point of bulk Si and only slightly below the melting point of a-Si (1,420 K for relaxed a-Si [31]). However, it is well known that the melting temperature of a nanoparticle decreases significantly with size, as a consequence of the additional free energy contribution of the surface to the overall Gibbs free energy [32]. For example, it has been shown that free-standing Si nanoparticles with a size of 20 nm melt at around 1,000 K [32]. On the other hand, nanoparticles embedded in a matrix can exhibit both melting-point click here depression and enhancement [33], and the actual melting behavior depends on the nature of the interface between the nanoparticle and the matrix. It has been found that when the interface between the nanoparticle and the matrix is coherent, the thermal vibration of the surface (interface) atoms selleck of the nanoparticle is suppressed. This suppression may prevent the melting of the nanocrystals’

surface and lead to an increase of the melting temperature. This kind of behavior has been found for lead nanocrystals in an aluminum matrix and was attributed to the lattice structures of the two crystals ‘locking up’, suppressing the vibration of the nanoparticles’ surface atoms [34]. Contrary to this, irregularly shaped and incoherent interfaces can be directly correlated with lowering of melting temperature of a nanoparticle [35]. In the investigated case, we expect

that directly after deposition we deal with amorphous Tryptophan synthase Si nanoparticles embedded in a disordered oxide matrix. Moreover, it is improbable that the sputtering technique allows deposit of coherent (epitaxial) interfaces between the amorphous nanoparticles and the matrix. Due to a large density gradient of the Si nanoparticles and the oxide host, when merged at their interface, the network topologies in either side deform in order to accommodate the transition [36]. Therefore, we expect the interfaces between Si nanoparticles and the matrix to be incoherent. This can be further supported by the latest findings of molecular dynamics simulations which have shown that the interface structure between Si-NCs and the matrix is generally highly porous on the silica side, making the contact with the Si-NCs discontinuous [37]. Taking this into account, we expect that the melting temperature of small, amorphous Si nanoparticles embedded in SRSO matrix might be depressed below the melting point of a-Si. If this is the case, melting of the nanoparticles may be possible at 1,100°C. Having this in mind, we suggest the following origin of the compressive stress observed in our experiment.

53 or greater than 3-fold higher risk than an individual with an average BMD. Note that the risk of fracture in individuals with an average BMD is lower than the average fracture risk, since fracture risk is a convex function of BMD. Table 4 Age-adjusted increase in risk of fracture (with 95 % confidence

interval) in women for every 1 SD decrease in bone mineral JQ-EZ-05 ic50 density (by absorptiometry) below the mean value for age (amended from [31], with permission Cytoskeletal Signaling inhibitor from the BMJ Publishing Group) Site of measurement Outcome Forearm fracture Hip fracture Vertebral fracture All fractures Distal radius 1.7 (1.4–2.0) 1.8 (1.4–2.2) 1.7 (1.4–2.1) 1.4 (1.3–1.6) Femoral neck 1.4 (1.4–1.6) 2.6 (2.0–3.5) 1.8 (1.1–2.7) 1.6 (1.4–1.8) Lumbar spine 1.5 (1.3–1.8) 1.6 (1.2–2.2) selleck kinase inhibitor 2.3 (1.9–2.8) 1.5 (1.4–1.7) The performance characteristics of ultrasound are similar. Most studies suggest that measurements of broadband ultrasound attenuation or speed of sound at the heel are associated with a 1.5- to 2-fold increase in risk for each standard deviation decrease in the measured variable [32, 54]. Comparative studies indicate that these

gradients of risk are very similar to those provided by peripheral assessment of bone mineral density at appendicular sites by absorptiometric techniques to predict any osteoporotic fracture [31]. However, the WHO criteria for the diagnosis of osteoporosis cannot be applied to ultrasound results. Clinical risk factors A large number

of risk factors for fracture have been identified [55–57]. For the purposes of improving risk assessment, interest lies in those factors that contribute significantly to fracture risk over and above that provided by bone mineral density measurements or age [58]. A good example is age. The same T-score with the same technique www.selleck.co.jp/products/wnt-c59-c59.html at any one site has a different significance at different ages. For any BMD, fracture risk is much higher in the elderly than in the young [59]. This is because age contributes to risk independently of BMD. At the threshold for osteoporosis (T-score = −2.5 SD), the 10-year probability of hip fracture ranges 5-fold in women from Sweden depending on age (Fig. 1) [52]. Thus, the consideration of age and BMD together increases the range of risk that can be identified. Fig. 1 Ten-year probability of hip fracture in women from Sweden according to age and T-score for femoral neck BMD [52] with kind permission from Springer Science and Business Media Over the past few years, a series of meta-analyses has been undertaken to identify additional clinical risk factors that could be used in case finding strategies, with or without the use of BMD. There are a number of factors to be considered in the selection of risk factors for case finding. Of particular importance, in the setting of primary care, is the ease with which they might be used.

[20] who prepared Zn3N2 using NH3, while the PL at 2.0 eV is closer to 2.3 eV found by Futsuhara et al. [12]. Different PL and optical energy band gaps have, therefore, been obtained for Zn3N2 using different growth

methods and conditions. Interestingly, the PL peak of the Zn3N2 layers at 2.9 eV shown in Figure  1 was enhanced by increasing the flow of NH3 or by adding H2 which also led to a suppression of the side CP673451 emission at 2.0 eV. The same has also been observed in the growth of GaN NWs or the conversion of β-Ga2O3 into GaN NWs, where find more the band edge emission at 3.4 eV was boosted using a high flow of H2 along with NH3 since it passivates surface states or defects within the GaN NWs. Therefore, at first sight, it appears that the main band edge of the Zn3N2 layers grown here is ≈2.9 eV which is close to the PL of Zn3N2 layers obtained by a variety

of other methods [21]. However, the energy band gap of Zn3N2 is still a controversial issue, and the optical band gap may not correspond to the fundamental energy gap as will be discussed later in more detail. No Zn3N2 NWs were obtained on Au/Si(001) by changing the temperature between 500°C and 700°C, flow of NH3, or the thickness of Au between 0.9 and 19 nm while no deposition took place on plain Si(001). This is in direct contrast to the case of ZnO NWs which were obtained readily on Au/Si(001) at 500°C to 600°C by the reaction of Zn with residual O2 under an inert flow of 100 sccms Ar by reactive vapour transport or directly on Si(001) without any Au via a self-catalysed check details vapour solid mechanism. The ZnO NWs showed Tolmetin clear peaks in the XRD as shown in Figure  2, corresponding to the hexagonal wurtzite crystal structure of ZnO. Figure 2 XRD spectra of ZnO NWs’ lower trace. Inset shows the PL of the ZnO NWs and square of the absorption versus energy. A typical PL spectrum of the ZnO NWs obtained on Au/Si(001) is shown in Figure  2 with a peak at 390 nm corresponding to 3.2 eV, which is in excellent agreement with the abrupt onset in the absorption measured from

ZnO NWs grown on 1.0 nm Au/quartz, shown as an inset in Figure  2. Here, it should be noted that the broad PL of the ZnO NWs at ≈2.0 eV (≡600 nm) is attributed to the radiative recombination of the carriers’ occupying defect states that are located energetically in the upper half of the energy band gap, as we have shown in the past for MO NWs such as SnO2 and β-Ga2O3 using ultrafast transient absorption-transmission pump-probe spectroscopy [5, 22]. This broad PL is not desirable in optoelectronic devices as it represents a competing radiative recombination path which acts to reduce the main band-edge emission. While we did not obtain any Zn3N2 NWs on Au/Si(001), we found that the reaction of Zn with 250 to 450 sccm NH3 including 50 sccm H2 over 1.

Crawford M, Brawner E, Batte K, Yu L, Hunter MG, Otterson GA, Nuovo G, Marsh CB, Nana-Sinkam SP: MicroRNA-126 inhibits invasion in non-small cell lung carcinoma cell lines. GDC-0449 price Biochem Biophys Res Commun 2008, 373:607–612.PubMedCrossRef 24. Yu SL, Chen HY, Chang GC, Chen CY, Chen HW, Singh S, Cheng CL, Yu CJ,

Lee YC, Chen HS, Su TJ, Chiang CC, Li HN, Hong QS, Su HY, Chen CC, Chen WJ, Liu CC, Chan WK, Li KC, Chen JJ, Yang PC: MicroRNA signature predicts survival and relapse in lung cancer. Cancer Cell 2008, 13:48–57.PubMedCrossRef 25. Markou A, Tsaroucha EG, Kaklamanis L, Fotinou M, Georgoulias V, Lianidou ES: Prognostic value of mature microRNA-21 and microRNA-205 overexpression in non-small cell lung cancer by quantitative real-time RT-PCR. Clin Chem 2008, 54:1696–1704.PubMedCrossRef 26. Weiss GJ, Bemis LT, Nakajima E, Sugita M, Birks DK, Robinson WA, Varella-Garcia M, Bunn PA Jr, Haney J, Helfrich BA, Kato H, Hirsch FR, Franklin WA: EGFR regulation by microRNA in lung cancer: correlation with clinical response and survival to gefitinib and EGFR expression in cell lines. Ann Oncol 2008, 19:1053–1059.PubMedCrossRef 27. Guo C, Sah JF, Beard L, Willson JK, Markowitz SD, Guda K: The noncoding RNA, miR-126, suppresses the growth of neoplastic cells by targeting phosphatidylinositol 3-kinase signaling and is frequently lost

in colon cancers. Genes Chromosomes Cancer 2008, 47:939–946.PubMedCrossRef 28. Kefas B, Godlewski J, Comeau L, Li Y, Abounader R, Hawkinson M, Lee J, Fine H, Chiocca EA, Lawler S, Purow B: microRNA-7 inhibits the epidermal growth factor receptor and the Akt pathway and is down-regulated IWP-2 in glioblastoma. Cancer Res 2008, 68:3566–3572.PubMedCrossRef Authors’ contributions YBG: Conceived and designed the experiments; WSC, JNH: Performed the experiments and analysed the data; HLY, CMX, YCL, ZGS: Contributed reagents/material/analysis tools/. All authors read an approved the final draft.”
“Background Glycosylated antigens, important components of glycolipids and glycoproteins, are widely expressed on cell membrane and are involved in cell adhesion,

recognition, and signal transduction [1]. The alterations of type II sugar chains, such as Lewis × and Lewis y, are common in ovarian cancer: 75% of epithelial ovarian cancers have overexpression of Lewis y antigen Phospholipase D1 which shows obvious relationship with prognosis; tumor marker CA125 in epithelial ovarian cancer also contains Lewis y structure [2, 3]. Alpha1, 2-fucosyltransferase (α1, 2-FT) is a key enzyme for STA-9090 nmr synthesizing Lewis y antigen. In our previous study, we successfully transferred α1, 2-FT gene into ovarian cancer cell line RMG-I and established a cell line RMG-I-H with stable high expression of Lewis y antigen, which showed obviously enhanced malignant behaviors [4–6]. CD44, one of important adhesive molecules on cells, is involved in the adhesion and metastasis of tumor cells and plays an important role in tumor development [7–10], but the regulatory mechanism is unclear yet.

In an overlay of the spectra from all isolates included in this study (Figure 2) one particular mass (A, m/z = 5303) separated CC 21/ST 21 C. jejuni isolates positive for TLP7m+c and of bovine origin from all others (Figure 3). Two additional masses separated ggt-positive C. jejuni isolates from ggt-negative ones. The majority of isolates displayed a peak at m/z = 5496 (C), which is replaced by neighboring peaks in specific isolates. The ggt- and cj1365c-postive

C. jejuni isolates (MLST-ST 22) showed a shift of this peak from m/z = 5496 to ~5479 (B). In contrast ZD1839 purchase to that the ggt-positive but cj1365c- and cstII-negative isolates (MLST ST-45) showed a shift of this peak into the opposite direction to m/z = 5523 (D). Figure 2 Overlay of ICMS spectra (Overview of entire MALDI-TOF MS spectrum). General overview of the whole MALDI-TOF-MS spectrum of the C. jejuni strains NCTC 11168 (red) and 81-176 (blue). The numbers above the peaks indicate their m/z-value. The shaded area marks the mass range that

is detailed in Figure 3. Figure 3 Overlay of ICMS spectra (Detail of Figure 2 ). Overlay of ICMS spectra selleck inhibitor of all isolates led to the identification of characteristic peaks for specific C. jejuni subgroups. Peak A (m/z = 5303; red) is specific for isolates of MLST-ST 21 expressing a dimeric form of the formic acid specific chemotaxis receptor Tlp7m+c. The majority of isolates shows a peak

at m/z = 5496 (peak C, dark blue). Ggt- and cj1365c-postive isolates (MLST-ST 21) show a shift of this peak to m/z = 5479 (peak B, light blue), whereas ggt-positive but cj1365c- and cstII-negative isolates (MLST-ST 45) show a shift of this peak to m/z = 5523 (peak D, green). Comparison of phylogenetic and phyloproteomic analyses To determine if there was a more global correlation between phyloproteomic and phylogenetic relatedness, the two dendrograms obtained by PCA and MLST clustering Myosin were compared (Figure 4). Figure 4 Comparison of the ICMS-spectra-based PCA-phyloproteomic tree with the phylogenetic MLST-based UPGMA-tree. Most of the Tlp7m+c + isolates cluster together in the ICMS-spectra-based PCA-dendrogram as well as the MLST-based 4SC-202 mw UPGMA-tree (orange); ggt+ isolates of MLST-CC 22, CC 45, and CC-283 form a common cluster in the PCA-tree (IIb2 + 3) whereas MLST-CC 42 isolates (mixed ggt+/-) cluster together with MLST-CC 257 isolates (dmsA +, ansB + but ggt -). The MLST-based UPGMA-dendrogram splits at two bifurcations into a minor and a major group. At the third bifurcation the remaining isolates form two approximately equal groups. In each of both groups, subgroups positive for dmsA and ansB and predominantly also for ggt are present.

In parallel to our study, however, there are other

recent studies examining the toxicological effects of other compounds which have similarly studied 6 animals per condition [33, 34]. Creatine monohydrate (equivalent to 2.5 g/dose for humans) is also a major ingredient in the WPH-based supplement. However, creatine monohydrate does not alter glucose tolerance or insulin sensitivity and is not insulinogenic nor does it affect circulating leucine concentrations [35]. With regard to other major ingredients present in the WPH-based supplement, L-citrulline has not been shown to impact circulating insulin and/or leucine levels [36], although vitamin C has been shown to reduce insulin in type II diabetes patients over chronic supplementation periods [37], and L-lysine may stimulate insulin secretion from pancreatic

beta cells [38]. Therefore, beyond the active biopeptides that exist in the WPH formulation, other check details ingredients may have influenced the insulin response. Finally, while we examined the postprandial circulating leucine response to a WPH-based supplement versus WPI, it remains unknown as to whether or not potential unknown biologically active peptide fragments that occur during the whey hydrolysis process spike in the bloodstream after feeding relative to WPI [this aspect of food science is reviewed Compound C datasheet in [39]. In this regard, future animal and/or human studies should PRKACG pursue this exciting and unexplored nutraceutical research area in order to determine if WPH supplementation with exercise confer

positive skeletal muscle anabolic responses due to potential increases in circulating bioactive peptide fragments relative to other protein sources. Conclusions In summary, our rodent feeding model uniquely found that the WPH-based supplement elicited greater transient leucine with a subsequent increased insulin response relative to the WPI. Given these data in conjunction with the recent data demonstrating that WPH may possess biologically active peptide fragments [5], it will be of future interest to compare the anabolic effects of WPI- versus WPH-based supplements surrounding resistance training and/or the effect of WPH-based supplements in persons with diminished insulin secretion. Our 30-day feeding rodent model suggests that WPH-based supplements are safe to consume for one month in rats and may confer satiating effects which reduced total food intake, Chk inhibitor albeit the relatively short-term feeding study did not unveil significant alterations in total fat mass between the administered dosages. In this regard, longer-term human studies might be performed in order to examine the potential weight regulatory effects that WPH-based products (i.e., meal-replacement shakes) may exhibit on overweight and obese populations. Acknowledgements This study was funded in full by Scivation, Inc. The authors disclose no financial consulting benefits from Scivation, Inc.

1 (ANOVA). Interleukin 6, IL-6 There

were no differences between groups at baseline and after treatment. IL-6 concentrations were unremarkable and within normal range before exercise (< 11.3 pg . mL-1), but we observed a significant increase from pre to post exercise above normal in both groups (P = 0.001, Figure 5) at baseline buy GDC 0032 and after 14 weeks of treatment. Figure 5 Plasma concentrations of interleukin-6 in trained men before and after 14 weeks of treatment, and pre/post a triple step test cycle ergometry. Pro with probiotics supplemented group, Plac placebo group, Ex exercise, wk week; n = 11 (probiotic supplementation), n = 12 (placebo). Values are means ± SD. There were significant differences from pre to post exercise: PEx < 0.05 (ANOVA). Discussion Athletes exposed to high intense exercise show increased occurence of GI symptoms like cramps, diarrhea, bloating, nausea, and bleeding [31, 32]. These symptoms have been associated with alterations in intestinal permeability and decreased Selleck Pevonedistat barrier function [33, 34] and subsequent with inflammation and oxidative stress [22, 23]. For this investigation we assembled a panel of surrogate markers related to increased intestinal permeability, oxidative stress and inflammation. The study was primarily focussed on the effects of

14 weeks multi-species probiotic supplementation on intestinal barrier function in trained men compared to a placebo group (primary outcome). The secondary TGF-beta Smad signaling outcome was to evaluate the influence of the probiotic supplementation and the model of exercise on markers of oxidative stress and inflammation. The resulting data show that, after the 14 weeks study period i) the probiotics decreased stool zonulin concentrations – a modulator of intestinal barrier function – from slightly above normal into the physiolgical range; ii) the probiotic supplementation decreased protein oxidation and the chronic inflammatory marker TNF-α; and iii) the

model of exercise did not induce oxidative stress but increased concentrations of the inflammatory cytokine IL-6 in this cohort of endurance trained men. Markers of intestinal permeability Zonulin is regarded as a phyiological modulator of intercellular Staurosporine order tight junctions and a surrogate marker of impaired gut barrier [19, 35–37]. Beside liver cells, intestinal cells can synthesize zonulin and the zonulin system can be activated by dietary proteins (especially gliadin) or enteric bacteria [21, 38]. We can exclude a dietary influence on the observed changes in zonulin concentrations as our subjects followed strictly all dietary instructions and did not change their diet during the study period. To our best knowledge this study reports for the first time that probiotic supplementation can reduce zonulin concentrations in feces of trained men. The observed reduction is all the more remarkable as mean concentrations were slightly above normal at baseline (ref. range: < 30 ng .

The carbohydrate content in the G drink was 66 g.L-1, which is approximately in-line with the current American College of Sports

Medicine recommendations [4]. These guidelines were based on the understanding that carbohydrates ingested during exercise could only be oxidized at a maximum rate of 1 g.min-1[33]. However, advances in carbohydrate metabolism research have determined up to 1.75 g.min-1 can be oxidized when using multiple transportable carbohydrates, such as glucose and fructose [34]. As such, the carbohydrate content in the INW drink was comprised of glucose and fructose delivered in a 2:1 ratio at 1.3 – 1.5 g.min-1 based on a concentration of 90 g.L-1. Previous work has determined this ratio of carbohydrate delivered in solution and ingestion at 1.5 g.min-1 can improve

exogenous carbohydrate metabolism during exercise by 13% [35] to 48% [36] compared to consuming an isocaloric find more glucose only solution. While carbohydrate oxidation was not measured in this study, consuming a drink with high carbohydrate concentration using multiple transporters has a potentially BI 2536 chemical structure powerful effect for sailing athletes, as World Cup regattas last 5–7 days with up to three hours of competitions per day. Therefore, reducing endogenous carbohydrate oxidation could potentially preserve stored muscle glycogen energy for later in the competition, which has previously been found to have a performance enhancing effect [37]. During competition, sailors can spend anywhere from two hours to six hours on-water, with time divided between warm-up, racing and waiting for changes in wind and weather and cool-down. Given the length of time on-water, the co-ingestion of carbohydrates Thalidomide and protein is necessary to prevent extended periods of muscle protein breakdown. Research examining the addition of whey protein to carbohydrate electrolyte beverages has revealed inconsistent results for improved athletic performance in both acute exercise [38, 39] and cycling time trials [40, 41]. In these studies, the addition of protein to an experimental beverage was focused on improving athletic performance

in acute exercise. In contrast, the addition of protein to a carbohydrate electrolyte drink used during multi-day competitions may be more appropriate for metabolic reasons and worthy of continued investigation. Saunders et al. [42] found the use of a fluid replacement drink fortified with protein during a two cycle-to-exhaustion tests within the same day was effective in attenuating the nutritional deficit incurred during exercise and helped to reduce skeletal muscle damage compared to a carbohydrate electrolyte drink alone. Therefore, performing multiple bouts of exercise within a day or consecutive days of https://www.selleckchem.com/products/lcz696.html competition may be necessary to fully observe the nutritional and physiologic effects of protein ingested with a carbohydrate electrolyte beverage during exercise [43].

PLB2 was underexpressed in biofilms grown in the MTP and in the in vivo and RHE models (up to 12 h), but this gene was upregulated in biofilms grown in the CDC reactor and in the RHE model (after 24 h and 48 h). Expression levels of LIP genes in biofilms The expression levels of LIP genes in biofilms buy Z-DEVD-FMK at Temsirolimus selected time points in the various model systems are shown in Additional file 3. LIP2, LIP4 and LIP5 were

overexpressed in biofilms grown in all model systems at several time points or during the entire time course. Furthermore, LIP1, LIP6, LIP9 and LIP10 were upregulated in biofilms grown in the two in vitro models but not in the in vivo and RHE models. LIP3 was overexpressed in biofilms grown in the two in vitro models, while this gene was downregulated in the in vivo and RHE models. LIP7 was upregulated in biofilms grown in both in vitro models and in the in vivo model, but not in the RHE model. Similar results were obtained for LIP8, except that this gene was downregulated in biofilms grown in the MTP. mTOR phosphorylation For all the LIP genes (except LIP4), model-dependent gene expression levels

were observed. LIP1, LIP2, LIP9 and LIP10 were highly overexpressed in biofilms grown in both in vitro models, whereas LIP3 and LIP5-7 were highly upregulated only in the CDC reactor. On the other hand, LIP genes were not expressed at a high level in biofilms grown in the in vivo and RHE models. Extracellular lipase

activity Extracellular lipase activity in the supernatant derived from start cultures or from biofilms grown in the MTP and RHE model was determined using a fluorogenic substrate, 4-methylumbelliferyl (4-MU) palmitate. The relative slope (biofilms versus start cultures) of the fluorescence-time curves obtained from biofilms grown at selected time points in the MTP or RHE model is shown in Fig. 4. No differences in lipase activity were observed between biofilms grown for 1 h in the MTP and planktonic cells. Between 1 h and 24 h of biofilm growth in the MTP, lipase activity increased and then remained stable from 24 h up to 72 h. A marked increase in lipase activity was detected between 72 h and 144 h of biofilm growth in the MTP. In the RHE model after 1 h, lipase activity was approximately 100 fold higher than the lipase activity in planktonic cells. Exoribonuclease Lipase activity increased during further biofilm formation and was more than 1000 fold higher after 48 h of biofilm growth in the RHE model, compared to that in planktonic cells. Figure 4 Extracellular lipase activity of sessile C. albicans cells. Extracellular lipase activity in the supernatant of sessile and planktonic C. albicans cells was determined using 4-MU palmitate. Relative slopes (%) of biofilms versus start cultures (derived from fluorescence-time curves) are shown for biofilms grown at selected time points in the MTP and RHE model.

Nevertheless, the data clearly confirmed such activity of the catalytic

fragment [12, 30]. It remains to be determined www.selleckchem.com/products/AG-014699.html whether the LytM catalytic domain can be released under physiological circumstances. A proteomic study of the S. Selleckchem Alvocidib aureus cell wall envelope fraction has identified only full length LytM (with a molecular mass of approximately 40 kDa and a pI around 6), but not in the predicted active form [33]. Although the physiological role of LytM and its catalytic domain remains uncertain, the catalytic domain has properties that could make it attractive as a potential antistaphylococcal agent. First, the protein can be easily overexpressed in Escherichia coli with very high yields and is easy to purify [30]. Moreover, preliminary in vitro experiments indicated that in certain conditions BTK inhibitor LytM185-316 was similarly effective as lysostaphin in clearing turbid cell wall suspensions. Therefore, we proceeded to compare lysostaphin and LytM in a new mouse model of staphylococcal infection. The efficacy of lysostaphin was confirmed in the new model as well. Surprisingly, the catalytic domain of LytM was no more effective than control. This

finding prompted us to compare properties of the two proteins in greater detail in vitro. Here, we report the in vivo observations and the in vitro properties of lysostaphin and LytM that might explain the different treatment outcomes. Results Chronic contact eczema model of staphylococcal infection A new chronic dermatitis model of staphylococcal infection for in vivo functional studies was developed. Following standard procedures, mice were sensitized by epicutaneous application of 4-ethoxymethylene-2-phenyloxazolone (oxazolone, Sigma) on the abdomen skin. Six days later and subsequently every second day

they were challenged Erlotinib with oxazolone applied to the ears. The treatment led to the development of chronic contact eczema in the treated ear, but not in the contralateral ear, which was left untreated as a control (Additional file 1). Preliminary experiments were run to establish a suitable S. aureus dose for the infection experiments. 106, 107, 108, and 109 CFUs of S. aureus strain LS-1 were spread on both ears of one mouse each. Mice were sacrificed two days later, ears were homogenized and S. aureus colony forming units (CFUs) counted. 106  S. aureus cells per ear were sufficient to establish infection in oxazolone-treated, inflamed mouse ears, but not in non-oxazolone treated ears (data not shown). To establish the time course for the infection, 106  S. aureus cells were applied to the oxazolone-treated, inflamed ears and to the non-oxazolone treated, contralateral control ears. At different time points following inoculation, mice were sacrificed, ears homogenized and S. aureus colony forming units (CFUs) counted. In non-oxazolone treated control ears, no bacteria were found after the application of 106  S. aureus cells.