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The spread of antibiotic-resistant pathogenic bacteria is an increasing health issue worldwide. A possible origin of antibiotic resistance could be the persistence of antibiotics in the aquatic environment. To tackle this problem, restricted control of application of antibiotics in human and veterinary medicine has been proposed. However, these measures do not prevent the spreadof antibiotic resistance but may delay the process, since antibiotics are still continuously emitted into the environment and many persist there. Derived from ciprofloxacin (CIP), CIP-Hemi, a fluoroquinolone with improved environmental properties, was developed following the benign by design approach and using insilico and in vitro methods. CIP-Hemi was designed to maintain its required metabolic stability (human liver microsomes, intestinal microsomes, blood plasma) and antibiotic activity (MIC in the μg mL−1 range) against the target while transforming into an inactive fragment (CIP-d-CP) and a degradable linker present under acidic conditions, e.g., after excretion or when released into theenvironment. Moreover, CIP-Hemi and CIP-d-CP showed weaker cytotoxic and mutagenic or genotoxic effects compared to the parent compound CIP and therefore underline the feasibility of CIP-Hemi as a viable antibiotic drug candidate, demonstrating benign by design as a promising approach.

Prudent use of antibiotics in livestock is widely considered to be important to prevent antibiotic resistance. This study aimed to evaluate the interactions between biofilms and veterinary antibiotics in therapeutic concentrations administrated via drinking water through a standardized experimental setup. In this context, two biofilms formed by pseudomonads (Pseudomonas (P.) aeruginosa or P. fluorescens) and a susceptible Escherichia (E.) coli strain were developed in a nutrient-poor medium on the inner surface of polyvinyl chloride pipe pieces. Subsequently, developing biofilms were exposed to sulfadiazine/trimethoprim (SDZ/TMP) or tylosin A (TYL A) in dosages recommended for application in drinking water for 5 or 7 days, respectively. Various interactions were detected between biofilms and antibiotics. Microbiological examinations revealed that only TYL A reduced the number of bacteria on the surface of the pipes. Additionally, susceptible E. coli survived both antibiotic treatments without observable changes in the minimum inhibitory concentration to 13 relevant antibiotics. Furthermore, as demonstrated by HPLC-UV, the dynamics of SDZ/TMP and TYL A in liquid media differed between the biofilms of both pseudomonads over the exposure period. We conclude that this approach represents an innovative step toward the effective evaluation of safe veterinary antibiotic use.

Antibacterial agents play important roles in the treatment of bacterial infections. However, the development of antimicrobial resistance (AMR) and carry-over of substances into the environment are several problems arising during oral treatment of bacterial infections. We assessed AMR development in commensalIn each trial, six pigs were treated with enrofloxacin via powder, granulate or pellet forms in two time periods (days 1-5 and 22-26). Four pigs served as untreated controls. The minimum inhibitory concentration (MIC) was determined to evaluate AMR development. Analysis of enro- and ciprofloxacin was performed with high performance liquid chromatography.Non-wildtypeThis study indicates that the kind of the oral dosage form of antibiotics affects environmental contamination and AMR development in commensal

BACKGROUND AND PURPOSE: Th9 cells represent a recently defined subset of CD4(+) T‐helper cells, characterized by a high production of IL‐9. They are found at increased frequency in lesions of atopic dermatitis, where IL‐9 is also elevated. As histamine is up‐regulated in lesions of inflammatory skin diseases, we investigated the expression profile of histamine receptors and their functional role on Th9 cells. EXPERIMENTAL APPROACH: Naïve CD4(+) T‐cells were purified from human peripheral blood mononuclear cells, using magnetic beads and further differentiated into Th9 cells. During differentiation, cells were additionally stimulated with histamine receptor agonists or left untreated. Histamine receptor expression as well as IL‐9 production was measured. KEY RESULTS: As proof of a successful differentiation, IL‐9 production was measured at mRNA and protein level. Expression of mRNA for histamine H(1), H(2) and H(4) receptors were up‐regulated in differentiated Th9 cells compared to Th0 cells, while no mRNA for the H(3) receptor was detectable. Stimulation of Th9 cells with histamine significantly up‐regulated expression of mRNA and protein for IL‐9 . Experiments with specific histamine receptor agonists and antagonists revealed that this up‐regulation was mediated by H(4) receptors. CONCLUSIONS AND IMPLICATIONS: In summary, our study demonstrates a functional role for histamine H(4) receptors on Th9 cells, which might amplify the pro‐inflammatory potency of these cells. Together with earlier studies on Th2 and Th17 cells, this study underlines the promising approach for the use of H(4) receptor antagonists in inflammatory and allergic diseases such as atopic dermatitis. LINKED ARTICLES: This article is part of a themed section on New Uses for 21st Century. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.3/issuetoc

Background The aim of this study was to establish precision-cut bovine udder slices (PCBUS) as an in-vitro-model to investigate pathophysiological processes in the early phase of mastitis in order to have the possibility to investigate new therapeutic approaches for the treatment of such udder inflammation in later studies. Furthermore, this model should contribute to substitute in-vivo-experiments. Bovine mastitis is one of the most common and costly infectious diseases in the dairy industry, which is largely associated with the use of antimicrobial agents. Given this problem of antimicrobial resistance, it is essential to step up research into bacterial infectious diseases. Thus, the transfer of the in-vitro-model of precision-cut tissue slices to the bovine udder enables broad research into new therapeutic approaches in this area and can also be used to address issues in basic research or the characterisation of complex pathophysiological processes. Results A stimulation with LPS, PGN or the combination of both substances (LPS:PGN) demonstrates the ability of the PCBUS to react with a significant secretion of IL-1ß, TNF-α and PGE2. Conclusion The slices represent an instrument for investigating pharmacological interactions with udder tissue, which can be useful for studies on pharmacological questions and the understanding of complex pathophysiological processes of infection and inflammation.

The naturally occurring betulinic acid (BA) and its derivative NVX-207 show anticancer effects against equine malignant melanoma (EMM) cells and a potent permeation in isolated equine skin in vitro. The aim of the study was to determine the in vivo concentration profiles of BA and NVX-207 in equine skin and assess the compounds' local and systemic tolerability with the intent of developing a topical therapy against EMM. Eight horses were treated percutaneously in a crossover design with 1% BA, 1% NVX-207 or a placebo in a respective vehicle twice a day for seven consecutive days with a seven-day washout period between each formulation. Horses were treated at the neck and underneath the tail. Concentration profiles of the compounds were assessed by high-performance liquid chromatography in the cervical skin. Clinical and histopathological examinations and blood analyses were performed. Higher concentrations of NVX-207 were found in the skin compared to BA. Good systemic tolerability and only mild local adverse effects were observed in all three groups. This study substantiates the topical application of BA and NVX-207 in further clinical trials with horses suffering from EMM; however, penetration and permeation of the compounds may be altered in skin affected by tumors.

Background In orthopedics, the treatment of implant-associated infections represents a high challenge. Especially, potent antibacterial effects at implant surfaces can only be achieved by the use of high doses of antibiotics, and still often fail. Drug-loaded magnetic nanoparticles are very promising for local selective therapy, enabling lower systemic antibiotic doses and reducing adverse side effects. The idea of the following study was the local accumulation of such nanoparticles by an externally applied magnetic field combined with a magnetizable implant. The examination of the biodistribution of the nanoparticles, their effective accumulation at the implant and possible adverse side effects were the focus. In a BALB/c mouse model (n = 50) ferritic steel 1.4521 and Ti90Al6V4 (control) implants were inserted subcutaneously at the hindlimbs. Afterwards, magnetic nanoporous silica nanoparticles (MNPSNPs), modified with rhodamine B isothiocyanate and polyethylene glycol-silane (PEG), were administered intravenously. Directly/1/7/21/42 day(s) after subsequent application of a magnetic field gradient produced by an electromagnet, the nanoparticle biodistribution was evaluated by smear samples, histology and multiphoton microscopy of organs. Additionally, a pathohistological examination was performed. Accumulation on and around implants was evaluated by droplet samples and histology. Results Clinical and histological examinations showed no MNPSNP-associated changes in mice at all investigated time points. Although PEGylated, MNPSNPs were mainly trapped in lung, liver, and spleen. Over time, they showed two distributional patterns: early significant drops in blood, lung, and kidney and slow decreases in liver and spleen. The accumulation of MNPSNPs on the magnetizable implant and in its area was very low with no significant differences towards the control. Conclusion Despite massive nanoparticle capture by the mononuclear phagocyte system, no significant pathomorphological alterations were found in affected organs. This shows good biocompatibility of MNPSNPs after intravenous administration. The organ uptake led to insufficient availability of MNPSNPs in the implant region. For that reason, among others, the nanoparticles did not achieve targeted accumulation in the desired way, manifesting future research need. However, with different conditions and dimensions in humans and further modifications of the nanoparticles, this principle should enable reaching magnetizable implant surfaces at any time in any body region for a therapeutic reason.

The addition of Ag to amorphous carbon (a-C) films is highly effective in tailoring the tribo-mechanical properties and biocompatibility. For biomedical applications, Ag-containing a-C (a-C:Ag) represents a promising film material for improving the biofunctional surface properties of Ti-based alloys. In a sputtering process, a-C:Ag films, with Ag contents up to 7.5 at.%, were deposited with a chemically graded TixCy interlayer onto Ti6Al4V. The tribo-mechanical and biocompatible properties of a-C:Ag were evaluated. The influence of the Ag content on these properties was analyzed and compared to those of uncoated Ti6Al4V. Raman spectroscopy reveals that the amount of incorporated Ag does not induce significant structural changes in the disordered network, only a reduced number of vacancies and sp3-coordinated C bonds within the sp2-dominant a-C network is assigned to the films with high Ag concentration. With increasing Ag content, stresses, hardness, and elastic modulus decrease from (2.02 ± 0.07) to (1.15 ± 0.03) GPa, from (17.4 ± 1.5) to (13.4 ± 0.9) GPa, and from (171.8 ± 8.1) to (138.5 ± 5.8) GPa, respectively. In tribometer tests, the friction behavior against Al2O3 in lubricated condition with a simulated-body-fluid-based lubricant is not affected by the Ag concentration, but the Al2O3 counterpart wear is reduced for all a-C:Ag films compared to a-C. The friction against ultra-high-molecular-weight polyethylene (UHMWPE) decreases continuously with increasing Ag concentration and the counterpart wear is lower at higher Ag contents. Compared to a-C:Ag, Ti6Al4V demonstrates lower friction against UHMWPE and higher friction against Al2O3. The a-C:Ag films are not exposed to abrasion by Al2O3 or pronounced material transfer of UHMWPE. The hardness difference and chemical affinity between the friction partners are decisive for the tribological behavior of a-C:Ag. Compared to Ti6Al4V, the a-C:Ag films show antibacterial activity against Staphylococcus aureus, while the proliferation of osteoblast-like cells is reduced by Ag.

Resorbable implants are highly beneficial to reduce patient burden since they need not be removed after a defined period. Currently, magnesium (Mg) and polymers are being applied as bioresorbable materials. However, for some applications the insufficient mechanical properties and high degradation rate of Mg cause the need for new materials. Iron (Fe)-based alloys are promising due to their biocompatibility and good mechanical properties, but their degradation rate is too low and needs to be adapted eg. via alloying with manganese (Mn). Besides, phases with high electrochemical potential lead to increased degradation of residual material with lower potential based on the galvanic coupling. Here, silver (Ag) is promising for the formation of such phases due to its high electrochemical potential (+0.8 V vs. SHE), immiscibility with Fe, biocompatibility, and anti-bacterial properties. Since remaining silver particles can lead to adverse consequences as thrombosis, these particles need to dissolve after the matrix material. Thus a silver alloy with high electrochemical potential, biocompatibility, and adjusted degradation behavior is required as an additive for iron-based bioresorbable materials. Several silver alloying systems are possible, but regarding the electrochemical potential and degradation behavior of binary alloys, calcium (Ca) and lanthanum (La) are best-suited considering their biocompatibility. Accordingly, this research addresses AgCa and AgCaLa alloys as additives for iron-based degradable materials with adapted degradation behavior

Methylxanthines positives in competition samples have challenged doping control laboratories and racing jurisdictions since methylxanthines are naturally occurring prohibited substances and often constituents of feed. For theobromine, an international threshold (renamed in International Residue Limit, IRL) of 2 µg/mL in urine has been established. On the basis of the data presented herein, a threshold or rather an IRL for theobromine in plasma of 0.3 µg/mL was proposed and was thereupon approved by the International Federation of Horseracing Authorities (IFHA). Official recommendations for reporting caffeine and theophylline are still lacking. The aim of the study was to investigate IRLs for theobromine in blood and for caffeine and theophylline in blood and urine. Therefore, a set of six administrations were carried out including both single i.v. and single oral administrations of caffeine, theobromine and theophylline. Plasma and urine concentrations were determined using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS). Applying the Toutain model approach an effective plasma concentration (EPC) of caffeine was estimated at 3.05 µg/mL, irrelevant concentrations in blood (IPC) and urine (IUC) approached 6 and 12 ng/mL, respectively. EPC of theobromine was calculated with 3.80 µg/mL, and irrelevant concentrations of theobromine were determined at 8 ng/mL in plasma and at 142 ng/mL in urine. Toutain modelling of the theophylline data produced an EPC, IPC, and IUC of 3.20 µg/mL, 6 ng/mL, and 75 ng/mL, respectively. The obtained irrelevant concentrations were used to postulate IRLs for theobromine in plasma and for caffeine and theophylline in plasma and urine. Copyright © 2016 John Wiley & Sons, Ltd.

The cytokine thymic stromal lymphopoietin (TSLP) is involved in the development and the progression of allergic diseases. It is mainly released by epithelial cells at barriers such as skin and gut in response to danger signals. Overexpression of TSLP in keratinocytes (KC) can provoke the development of a type 2 inflammatory response. Additionally, TSLP directly acts on sensory neurons and thereby triggers itch. Since histamine is also increased in lesions of inflammatory skin diseases, the aim of this study was to investigate possible effects of histamine as well as different histamine receptor subtype agonists and antagonists on TSLP production in KC. We therefore stimulated human KC with histamine in the presence or absence of the known TSLP-inductor poly I:C and measured TSLP production at protein as well as mRNA level. Histamine alone did not induce TSLP production in human KC, but pre-incubation with histamine prior to challenge with poly I:C resulted in a significant increase of TSLP production compared to stimulation with poly I:C alone. Experiments with different histamine receptor agonists (H1R: 2-pyridylethylamine; H2R: amthamine; H2R/H4R: 4-methylhistamine (4MH)) revealed a dominant role for the H4R receptor, as 4-MH in combination with poly I:C displayed a significant increase of TSLP secretion, while the other agonists did not show any effect. The increase in TSLP production by 4MH was blocked with the H4R antagonist JNJ7777120. This effect was reproducible also in the murine KC cell line MSC. Taken together, our study indicates a new role for the H4 receptor in the regulation of TSLP in keratinocytes. Therefore, blocking of the H4R receptor in allergic diseases might be promising to alleviate inflammation and pruritus via TSLP.

Gum arabic (GA) is a traditional herbal medicine from Acacia Senegal (L.) Willdenow trees, which consist of a complex mixture of polysaccharides and glycoproteins. It is used in daily applications for several diseases and is considered to protect against bacterial infections. The detailed mechanisms behind these observations are still unclear. In this study, we investigated the direct antibacterial activity of GA water and ethanol extracts against Staphylococcus (S.) aureus or Escherichia (E.) coli and the immunomodulating properties of those extracts on granulocytes as a first line of defense against bacteria. Firstly, the direct antimicrobial effect of GA was tested on three different S. aureus strains and two E. coli strains. The growth of bacteria was analyzed in the presence of different GA concentrations over time. GA water as well as ethanol extracts showed a significant growth inhibition in a concentration-dependent manner in the case of S. aureus Newman, S. aureus Rd5, and E. coli 25922, but not in the case of S. aureus USA300 and E. coli K1. Transmission electron microscopic analysis confirmed an antibacterial effect of GA on the bacteria. Secondly, the immunomodulatory effect of GA on the antimicrobial activity of bovine or human blood-derived granulocytes was evaluated. Interestingly, water and ethanol extracts enhanced antimicrobial activity of granulocytes by the induction of intracellular ROS production. In line with these data, GA increased the phagocytosis rate of E. coli. No effect was seen on neutrophil extracellular trap (NET) formation that mediates killing of extracellular bacteria such as S. aureus. In conclusion, we show that GA exhibits a direct antibacterial effect against some S. aureus and E. coli strains. Furthermore, GA boosts the antimicrobial activities of granulocytes and increases intracellular ROS production, which may lead to more phagocytosis and intracellular killing. These data might explain the described putative antimicrobial activity of GA used in traditional medicine.

Implant associated infections are still key problem in surgery. In the present study, the combination of a magnetic implant with administered magnetic nanoporous silica nanoparticles as potential drug carriers was examined in mice in dependence of local infection and macrophages as influencing factors. Four groups of mice (with and without implant infection and with and without macrophage depletion) received a magnet on the left and a titanium control on the right hind leg. Then, fluorescent nanoparticles were administered and particle accumulations at implant surfaces and in inner organs as well as local tissue reactions were analyzed. Magnetic nanoparticles could be found at the surfaces of magnetic implants in different amounts depending on the treatment groups and only rarely at titanium surfaces. Different interactions of magnetic implants, particles, infection and surrounding tissues occurred. The general principle of targeted accumulation of magnetic nanoparticles could be proven.

Gaining knowledge about the spread of resistance against antibacterial agents is a primary challenge in livestock farming. The purpose of this study was to test the effect of double antibiotic treatment (at days 10&ndash, 14 and days 26&ndash, 30) with enrofloxacin or solely environmental exposition (identical times, directly into the litter) on resistance against antibacterial agents in commensal Escherichia coli in comparison with the control (without treatment), depending on different flooring. A total of 720 Big 6 turkeys participated in three trials. Four different flooring designs were examined: An entire floor pen covered with litter, a floor pen with heating, a partially slatted flooring including 50% littered area, and a fully slatted flooring with a sand bath. A total of 864 Escherichia coli isolates were obtained from cloacal swabs and poultry manure samples at days 2, 9, 15, 21, and 35. The broth microdilution method (MIC) was used to determine the resistance of isolates to enrofloxacin and ampicillin. A double antibiotic treatment with enrofloxacin reduced the proportion of susceptible Escherichia coli isolates significantly in all flooring designs. Simulation of water losses had no significant effect, nor did the flooring design. Ampicillin-resistant isolates were observed, despite not using ampicillin.

Systematic survey of data from cases of suspected poisoning in small animal practices.In 11 exemplary selected small animal practices, patient files from cases of suspected poisoning over 2006/2007, data entry forms of poisonings 2009-2010 and the contact group, which are all patients with at least one visit in 2007, were analysed.In 2007, approximately 1 in 200 dog and 1 in 500 cat patients were presented with poisoning. More than 70 % of cases concerned dogs. Some breeds of hunting dogs were more frequently affected than expected from their percentage in the practice population. Suspicion of poisoning was retrospective mainly founded in neutered dogs. In addition to numerous unspecific symptoms, bleeding was frequently observed. With central nervous system symptoms or a critical general condition a founded suspicion was observed more frequently. In cases of unfounded suspicion, inflammation of the gastrointestinal tract was mostly present. Other frequently seen diseases were infections, tumours and autoimmune diseases. The main toxins in the retrospective evaluation were coumarin derivatives (37 %), drugs (10 %) and chocolate (7 %). The prospective survey yielded a higher percentage of poisoning with drugs and plants. The diagnosis was mainly based on case history and clinical signs. Therapy was predominantly symptomatic.Poisoning with coumarin derivatives is the most frequent intoxication in dogs, but also cats. The risk from permethrin for cats remains current. In daily practice, therapy is mostly symptomatic without any specific toxicological evidence. Consequently, the causative toxin is frequently unknown. Therefore, additional methods for elimination (stomach/rectal lavage, medical coal, lipid therapy) should be included as therapeutical options. For a successful systematic prospective survey in daily practice a good collaboration between practice and investigator is necessary.

Background In the European Union, various fluoroquinolones are authorised for the treatment of food producing animals. Each administration poses an increased risk of development and spread of antimicrobial resistance. The aim of this study was to investigate the impact of parenteral administration of enrofloxacin on the prevalence of enrofloxacin and ciprofloxacin susceptibilities in the commensal intestinal E. coli population. Methods E. coli isolates from faeces of twelve healthy pigs were included. Six pigs were administered enrofloxacin on day 1 to 3 and after two weeks for further three days. The other pigs formed the control group. MIC values were determined. Virulence and resistance genes were detected by PCR. Phylogenetic grouping was performed by PCR. Enrofloxacin and ciprofloxacin were analysed in sedimentation samples by HPLC. Results Susceptibility shifts in commensal E. coli isolates were determined in both groups. Non-wildtype E. coli could be cultivated from two animals of the experimental group for the first time one week after the first administration and from one animal of the control group on day 28. The environmental load with enrofloxacin in sedimentation samples showed the highest amount between days one and five. The repeated parenteral administration of enrofloxacin to pigs resulted in rapidly increased MIC values (day 28: MIC up to 4 mg/L, day 35: MIC ≥ 32mg/L). E. coli populations of the control group in the same stable without direct contact to the experimental group were affected. Conclusion The parenteral administration of enrofloxacin to piglets considerably reduced the number of the susceptible intestinal E. coli population which was replaced by E. coli strains with increased MIC values against enrofloxacin. Subsequently also pigs of the control were affected suggesting a transferability of strains from the experimental group through the environment to the control group especially as we could isolate the same PFGE strains from both pig groups and the environment.

The objective of this study was to evaluate the effects of different types of flooring designs on antimicrobial resistance in commensal Escherichia coli from turkeys treated with enrofloxacin. Two trials were performed with same feed, housing conditions and fattening duration, but with different flooring designs. Furthermore, the first trial was performed in an unchanged environment and the second trial in a changed environment. The flooring designs of the pens were assigned to four groups; G1 – entire floor pen covered with litter, G2 – floor pen with heating, G3 – partially slatted flooring including an area that was littered, G4 – fully slatted flooring with a sand bath. Enrofloxacin was given at days 10–14 via drinking water. The changed environment in the second trial was achieved by moving the animals to new pens with the respective same conditions as previously after antimicrobial administration at day 15. A total of 576 E. coli were isolated from cloacal swab and poultry manure samples. Sample collection was done before the treatment, after the treatment and at the end of the trials at day 35. The resistance of isolates to enrofloxacin and ampicillin was determined using broth microdilution A single treatment with enrofloxacin reduced the proportion of samples with susceptible E. coli isolates significantly in all flooring designs. Overall, frequencies of enrofloxacin resistance were significantly different between the unchanged and changed environment. At the same time, the proportion of ampicillin-resistant isolates increased in the first trial, although no ampicillin was applied in this study.

Extensive usage of fluoroquinolone antibiotics in livestock results in their occurrence in manure and subsequently in the environment. Fluoroquinolone residues may promote bacterial resistance and are toxic to plants and aquatic organisms. Moreover, fluoroquinolones may enter the food chain through plant uptake, if manure is applied as fertilizer. Thus, the presence of fluoroquinolones in the environment may pose a threat to human and ecological health. In this study, the biotransformation of enrofloxacin, marbofloxacin, and difloxacin by the fungus X. longipes (Xylaria) was investigated. The main metabolites were unequivocally identified as the respective N-oxides by mass spectrometry and nuclear magnetic resonance spectroscopy. Fungal-mediated N-oxidation of fluoroquinolones led to a 77-90% reduction of the initial antibacterial activity. In contrast to their respective parent compounds, N-oxides showed low cytotoxic potential and had a reduced impact on cell proliferation. Thus, biotransformation by X. longipes may represent an effective method for inactivating fluoroquinolones.

The effects of water-filtered infrared-A (wIRA) and of convective heat on viability, inflammation, inducible free radicals and antioxidative power were investigated in natural and viable skin using the ex vivo Bovine Udder System (BUS) model. Therefore, skin samples from differently treated parts of the udder of a healthy cow were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test, by prostaglandin E2 (PGE2) measurement and by electron spin resonance (ESR) spectroscopy. Neither cell viability, the inflammation status, the radical status or the antioxidative defence systems of the skin were significantly affected by wIRA applied within 30 min by using an irradiance of 1900 W m(-2) which is of relevance for clinical use, but which exceeded the maximum solar IR-A irradiance at the Earth's surface more than 5 times and which resulted in a skin surface temperature of about 45 °C without cooling and of about 37 °C with convective cooling by air ventilation. No significant effects on viability and on inflammation were detected when convective heat was applied alone under equivalent conditions in terms of the resulting skin surface temperatures and exposure time. As compared with untreated skin, free radical formation was almost doubled, whereas the antioxidative power was reduced to about 50% after convective heating to about 45 °C.

Pharmaceuticals are widely distributed in low concentrations in the water compartment. Conventional sewage treatment plants (STP) are not capable to remove pharmaceuticals to the full extent, so alternative methods such as ozonization or photooxidation are tested as additional stage. However, it has been shown that in many cases no complete mineralization is achieved during these processes and transformation products occur. Up to now only little is known about these transformation products in terms of their structure and toxicity. The antibiotic sulfathiazole (STZ) is used in veterinary medicine and it can be detected in different water matrices such as STP effluent or surface water. We tested the ability of photooxidation for degradation of STZ using a medium pressure mercury lamp. LC-UV showed the formation of several minor compounds and one main transformation product which has been isolated subsequently. Using NMR and high resolution mass spectrometry techniques, we were able to reveal the structure of promizole, an antituberculotic, used in the 1950s. This compound showed a reduced microbial activity in Brilliant Black Reduction Maximum Residue Level test. Furthermore, there was no difference in the effects of promizole when compared to STZ on cell toxicity and cell proliferation in two murine cell lines.

Sphingosine-1-phosphate (S1P) modulates many cell functions such as lymphocyte trafficking and signaling as well as keratinocyte proliferation. However, less is known about the specific effects of S1P on cytokine production, particularly on the interaction between dendritic cells (DCs) and keratinocytes, cell types which are crucial for the initiation and maintenance of chronic inflammatory skin diseases like atopic dermatitis or psoriasis. Especially the cytokines of the IL-12 family play a dominant role in many inflammatory diseases as they have a significant impact on T-helper cell function. In the present study we show that S1P decreased the production of the pro-inflammatory cytokines IL-12 and IL-23 in LPS-stimulated DCs via the common subunit p40 as well as in the crosstalk with activated keratinocytes. By using specific S1P receptor agonists (SEW2871, FTY720-P) and antagonist (JTE013) we identified an important role for S1P receptor 1 in the modulation of the cytokine profile. While diminishing IL-12 and IL-23 secretion, S1P enhanced IL-27 production in DCs. To elucidate the mechanism of the different impact on the IL-12 family cytokine production, we investigated the mitogen-activated protein kinase (MAPK) and phosphatidylinositide 3-kinase (PI3K) pathways in DCs. By using specific MAPK-Inhibitors (U0126, SB202190, SP600125) we demonstrated that ERK, p38 and JNK differently regulate each pathway of each cytokine. While p38 and JNK did not seem to play a role in the modulation properties of S1P on cytokine production, ERK is at least partially involved in the S1P mediated modulation of IL-12 and IL-27. The PI3K-Inhibitor abrogated the S1P-induced decrease of IL-12 and IL-23 secretion, while it had no influence on the S1P-induced increase of IL-27 production. These data implicate, that S1P has an anti-inflammatory impact on the production of IL-12 family cytokines, indicating therapeutic potential for S1P treatment of several inflammatory diseases like psoriasis.

Resorbable magnesium-based implants hold great promise for various biomedical applications, such as osteosynthesis and coronary stenting. They also offer a new therapeutic option for the treatment of chronic rhinosinusitis, but little data is yet available regarding the use of magnesium in the nasal cavity. To model this field of application, primary porcine nasal epithelial cells were used to test the biocompatibility of degrading pure magnesium and investigate whether the degradation products may also affect cellular metabolism. Magnesium specimens did not induce apoptosis and we found no major influence on enzyme activities or protein synthesis, but cell viability was reduced and elevated interleukin 8 secretion indicated proinflammatory reactions. Necrotic damage was most likely due to osmotic stress, and our results suggest that magnesium ion build-up is also involved in the interleukin 8 release. Furthermore, the latter seems to be mediated, at least in part, by the p38 signaling pathway. These effects probably depended on the accumulation of very high concentrations of magnesium ions in the in vitro set-up, which might not be achieved in vivo, although we cannot exclude that further, as yet unknown, factors played a role in the inflammatory response during the degradation process. In conclusion, the biocompatibility of pure magnesium with cells in the immediate vicinity appears less ideal than is often supposed, and this needs to be considered in the evaluation of magnesium materials containing additional alloying elements.

Background Histamine 4 receptor (H4R) antagonists are considered as new therapeutics for the treatment of atopic dermatitis (AD) and first clinical trials have already shown promising results. Histamine 1 receptor (H1R) antagonists are traditionally used to treat AD although the evidence for the efficacy is weak. The combined blockade of both, H1R and H4R, might provide synergistic anti-inflammatory. Objective The study was performed to test the anti-inflammatory potential of a combined treatment with an H1R and an H4R antagonist in a mouse AD model. Methods The development of ovalbumin-induced AD-like skin lesions was analysed mice treated with the H1R inverse agonist mepyramine, the H4R antagonist JNJ-39758979 or a combination of both. Results Mice treated with mepyramine plus JNJ-39758979 showed less severe skin lesions, with a diminished influx of inflammatory cells, a reduced epidermal thickening and a lower level of IL-33 in lesional skin. Scratching behaviour was ameliorated in mice treated with the combination. Moreover, total numbers of skin-draining lymph node cells and splenocytes were significantly reduced. Both substances given alone did not elicit this strong anti-inflammatory effect. Conclusion H1R and H4R antagonists provide synergistic anti-inflammatory effects in a mouse model of AD. The combined therapy with H1R and H4R antagonists might represent a new strategy for the treatment of AD.

At present, resorbable materials for implant applications are of great interest in biomedical engineering. Furthermore, the magnesium alloy MgNd2 provides unique mechanical and corrosive characteristics combined with appropriate biocompatibility, making it an ideal candidate for resorbable biomedical applications. MgNd2 provides low strength, enabling plastic deformation at ~80 MPa and a tensile elongation of ~30%, which is exceptional for magnesium alloys. Mass-loss analyses using simulated body fluid have exhibited a slow and homogeneous corrosion behavior in vitro, revealing a corrosion rate of less than 1 mm/year. Using cell viability and cytocompatibility tests, a general biocompatibility determined for MgNd2 showed no negative impact on cells. Due to excellent characteristics of MgNd2, it was successfully introduced as a resorbable stenting material within biological air-ducting tubuli and, furthermore, demonstrated desired in situ deformation characteristics.

Postoperative ileus (POI) is a severe complication following small intestinal surgery in horses. It was hypothesised that prokinetic effects of lidocaine, the most commonly chosen drug for treatment of POI, resulted from drug integration into smooth muscle (SM) cell membranes, thereby modulating cell membrane properties. This would probably depend on the structural and lipophilic characteristics of lidocaine. To assess the influence of molecular structure and lipophilicity on prokinetic effects in vitro, the current study compared the effects of lidocaine with four structure-related drugs, namely, mexiletine, bupivacaine, tetracaine and procaine. The response to cumulative drug administration and reversibility of effects were tested by measuring isometric contractile performance of equine jejunal circular SM strips, challenged by a standardised, artificial in vivo ischaemia-reperfusion injury. A second set of SM strips were incubated with the different drugs to determine changes in creatine kinase (CK) release. All drugs caused a drug-specific increase in contractility, although only lidocaine and mexiletine induced similar concentration-dependent curve progressions, significantly reduced CK release, and featured shorter recovery times of tissue contractility after washing, compared to bupivacaine and tetracaine. In was concluded that the structural and lipophilic similarity of mexiletine and lidocaine were responsible for the similar effects of these drugs on SM contractility and cell membrane permeability, which supported the hypothesis that prokinetic effects of lidocaine are based on interactions with SM cell membranes modulated by these features.

Background Although acetylsalicylic acid (ASA) is not frequently used as a therapeutic agent in horses, its metabolite SA is of special interest in equestrianism since it is a natural component of many plants used as horse feed. This led to the establishment of thresholds by horse sport organizations for SA in urine and plasma. The aim of this study was to investigate plasma and urine concentrations of salicylic acid (SA) after oral administration of three different single dosages (12.5 mg/kg, 25 mg/kg and 50 mg/kg) of acetylsalicylic acid (ASA) to eight horses in a cross-over designed study. Results In the 12.5 mg/kg group, SA concentrations in urine peaked 2 h after oral administration (2675 μg/mL); plasma concentrations peaked at 1.5 h (17 μg/mL). In the 25 mg/kg group, maximum concentrations were detected after 2 h (urine, 2785 μg/mL) and 1.5 h (plasma, 23 μg/mL). In the 50 mg/kg group, maximum concentrations were observed after 5 h (urine, 3915 μg/mL) and 1.5 h (plasma, 45 μg/mL). The plasma half-life calculated for SA varied between 5.0 and 5.7 h. The urine concentration of SA fell below the threshold of 750 μg/mL (set by the International Equestrian Federation FEI and most of the horseracing authorities) between 7 and 26 h after administration of 12.5 and 25 mg/kg ASA and between 24 and 36 h after administration of 50 mg/kg ASA. For ASA, IC50 were 0.50 μg/mL (COX-1) and 5.14 μg/mL (COX-2). For salicylic acid, it was not possible to calculate an IC50 for either COX due to insufficient inhibition of both cyclooxygenases. Conclusion The established SA thresholds of 750 μg//mL urine and 6.5 μg/mL plasma appear too generous and are leaving space for misuse of the anti-inflammatory and analgetic compound ASA in horses.