A microbiological assay to estimate the antimicrobial activity of parenteral tildipirosin against foodborne pathogens and commensals in the colon of beef cattle and pigs.

Tildipirosin (TIP) is a novel 16-membered-ring macrolide authorized for the treatment of bovine and swine respiratory disease. The pH dependency of macrolide antimicrobial activity is well known. Considering that the pH in the colon contents of growing beef cattle and pigs is usually below pH 7.0, the minimum inhibitory concentrations (MIC) of TIP against foodborne bacterial pathogens such as Campylobacter (C.) coli, C. jejuni and Salmonella enterica and commensal species including Enterococcus (E.) faecalis, E. faecium and Escherichia coli were determined under standard (pH 7.3 ± 1) or neutral as well as slightly acidic conditions. A decrease in pH from 7.3 to 6.7 resulted in an increase in MICs of TIP. Except for the MICs > 256 µg/mL observed in the resistant subpopulation of the C. coli and the Enterococcus species, the MIC ranges increased from 2-8 µg/mL to 64-> 256 µg/mL for Salmonella enterica and E. coli, from 8-16 µg/mL to 32-128 µg/mL for the two Campylobacter species, and from 4-32 µg/mL to 128-> 256 µg/mL for both Enterococcus species. To estimate the antimicrobial activity of TIP in the colon contents of livestock during recommended usage of the parenterally administered TIP (Zuprevo(®) ), and to compare this with the increased MICs at the slightly acidic colonic pH, we developed and validated a microbiological assay for TIP and used this to test incurred faecal samples collected from cattle and pigs. Microbiological activity of luminal TIP was determined in aqueous supernatants from diluted faeces, using standard curves produced from TIP-spiked faecal supernatants. The limit of quantification (LOQ) for TIP was 1 µg/mL (ppm). In a cattle study (n = 14), 3 of 28 faecal samples collected 24 and 48 h post-treatment were found to contain TIP above the LOQ (concentrations of 1.3-1.8 ppm). In another cattle study (n = 12) with faecal samples collected at 8, 24 and 48 h post-treatment, TIP concentrations were above the LOQ in 4 of the 8 h samples (1.2-2.6 ppm) and one of the 24-h samples (1.3 ppm). In a pig study (n = 12) with faecal samples collected 24, 48 and 72 h post-treatment, only one sample contained TIP above the LOQ (concentration 1.5 ppm). In another pig study (n = 12), with samples collected at 8, 24 48 and 96 h post-treatment, TIP concentrations were above the LOQ in one 8-h sample (1.1 ppm) and two 24-h samples (2.3 and 2.5 ppm). None of the 48-h and 96-h samples from these 4 studies contained measurable TIP concentrations. Thus, in cattle and pigs, only a small fraction of faecal samples collected up to 24 h postdosing contained measurable microbiologically active TIP, with its maximum limited to 2.6 µg/mL. This is several log2 dilution steps below the MICs of TIP against foodborne pathogens and commensals collected under acidic conditions comparable with those in the colonic contents and may explain a lack of intestinal dysbacteriosis with parenteral tildipirosin in livestock.

Pharmacokinetics of tildipirosin in porcine plasma, lung tissue, and bronchial fluid and effects of test conditions on in vitro activity against reference strains and field isolates of Actinobacillus pleuropneumoniae.

The pharmacokinetics of tildipirosin (Zuprevo(®) 40 mg/mL solution for injection for pigs), a novel 16-membered-ring macrolide for the treatment for swine respiratory disease (SRD), was investigated in studies collecting blood plasma and postmortem samples of lung tissue and bronchial fluid (BF) from swine. In view of factors influencing the in vitro activity of macrolides, and for the interpretation of tildipirosin pharmacokinetics in relation to minimum inhibitory concentrations (MIC), additional experiments were conducted to study the effects of pH, carbon dioxide-enriched atmosphere, buffers, and serum on tildipirosin MICs for various reference strains and Actinobacillus (A.) pleuropneumoniae field isolates. After single intramuscular (i.m.) injection at 4 mg/kg body weight, maximum plasma concentration (Cmax) was 0.9 µg/mL observed within 23 min (Tmax ). Mean residence time from the time of dosing to the time of last measurable concentration (MRTlast) and terminal half-life (T1/2) both were about 4 days. A dose-response relationship with no significant sex effect is observed for area under the plasma concentration-time curve from time 0 to the last sampling time with a quantifiable drug concentration (AUClast) over the range of doses up to 6 mg/kg. However, linear dose proportionality could not be proven with statistical methods. The time-concentration profile of tildipirosin in BF and lung far exceeded that in blood plasma. In lung, tildipirosin concentrations reached 3.1 µg/g at 2 h, peaked at 4.3 µg/g at day 1, and slowly declined to 0.8 µg/g at day 17. In BF, tildipirosin levels were 14.3, 7.0, and 6.5 µg/g at days 5, 10, and 14. T1/2 in lung was ∼7 days. Tildipirosin is rapidly and extensively distributed to the respiratory tract followed by slow elimination. Culture media pH and carbon dioxide-enriched atmosphere (CO2 -EA) had a marked impact on in vitro activity of tildipirosin in reference strains of various rapidly growing aerobic and fastidious bacteria including Histophilus (H.) somni ATCC 700025 and A. pleuropneumoniae ATCC 27090. For A. pleuropneumoniae ATCC 27090 testing conditions without CO2 -EA resulted in reduced acidification of culture media pH and a reduction in the minimum inhibitory concentrations compared to standard in vitro test conditions by 2 log2 dilution steps (4-fold) from 8 to 2 µg/mL. Supplementary buffering of standard culture media resulted in a reduction in the A. pleuropneumoniae (n = 8) MIC range by 4 log2 dilution steps (16-fold) from 8-16 to 0.5-1 µg/mL. Incremental supplementation of culture media with 50% serum resulted in noticeable shifts to lower minimum or maximum MICs by at least 2 log2 dilution steps (≥4-fold) in all aerobic and fastidious reference strains tested except for Pasteurella (P.) multocida. The MIC of A. pleuropneumoniae ATCC 27090 decreased by 2-4 log2 dilution steps (4 to 16-fold) from 8 to 0.5-2 µg/mL when 50% serum was added to the standard assay. Considering a higher presence of serum and the rather neutral pH conditions maintained in vivo, it is suggested to take the influence of these factors on in vitro activity into account when interpreting tildipirosin MICs for A. pleuropneumoniae in relation to pharmacokinetics.

Pharmacokinetics of tildipirosin in bovine plasma, lung tissue, and bronchial fluid (from live, nonanesthetized cattle).

The pharmacokinetics of tildipirosin (Zuprevo(®) 180 mg/mL solution for injection for cattle), a novel 16-membered macrolide for treatment, control, and prevention of bovine respiratory disease, were investigated in studies collecting blood plasma, lung tissue, and in vivo samples of bronchial fluid (BF) from cattle. After single subcutaneous (s.c.) injection at 4 mg/kg body weight, maximum plasma concentration (C(max)) was 0.7 µg/mL. T(max) was 23 min. Mean residence time from the time of dosing to the time of last measurable concentration (MRT(last)) and terminal half-life (T(1/2) ) was 6 and 9 days, respectively. A strong dose-response relationship with no significant sex effect was shown for both C(max) and area under the plasma concentration-time curve from time 0 to the last sampling time with a quantifiable drug concentration (AUC(last) ) over the range of doses up to 6 mg/kg. Absolute bioavailability was 78.9%. The volume of distribution based on the terminal phase (V(z)) was 49.4 L/kg, and the plasma clearance was 144 mL/h/kg. The time-concentration profile of tildipirosin in BF and lung far exceeded those in blood plasma. In lung, tildipirosin concentrations reached 9.2 µg/g at 4 h, peaked at 14.8 µg/g at day 1, and slowly declined to 2.0 µg/g at day 28. In BF, the concentration of tildipirosin reached 1.5 and 3.0 µg/g at 4 and 10 h, maintained a plateau of about 3.5 µg/g between day 1 and 3, and slowly declined to 1.0 at day 21. T(1/2) in lung and BF was approximately 10 and 11 days. Tildipirosin is rapidly and extensively distributed to the respiratory tract followed by slow elimination.

[Strategies for action to tackle health inequalities in Germany]. / Strategien zur Verminderung gesundheitlicher Ungleichheiten in Deutschland.

Against the background of health inequalities, the German Federal Centre for Health Education (BZgA) has coordinated the European project 'Closing the Gap: Strategies for Action to Tackle Health Inequalities in Europe'. Describing the state of the art of reducing health inequalities in each participating country has been one output of the EU project. The aim of this contribution is to present information for Germany with regard to research, political background, initiatives, quality and evaluation of interventions and public awareness. Despite the lack of a national strategy to tackle health inequalities, it can be concluded that there is a range of important activities which are supported by the federal government and which comprise different actors and sectors. Knowledge transfer across Europe can be helpful within the conception of a concerted action.

[Health promoting interventions for migrants. Analysis of the database "Health Promotion for the Socially Disadvantaged" www.gesundheitliche-chancengleichheit.de]. / Gesundheitsfördernde Angebote für Menschen mit Migrationshintergrund. Sonderauswertung der Projektdatenbank "Gesundheitsförderung bei sozial Benachteiligten" www.gesundheitliche-chancengleichheit.de.

The nationwide database "Health Promotion for the Socially Disadvantaged" (http:// www.gesundheitliche-chancengleichheit. de), set up by Federal Centre for Health Education (BZgA), includes about 2,700 projects, and amongst other activities also interventions for migrants living under socially disadvantaged circumstances. Based on qualitative interviews with the coordinators of some selected interventions, this contribution presents basic strategies and methods for reaching the target group.

[Health information database system of the Federal Center for Health Education (FCHE)]. / Die Fachdatenbanken der Bundeszentrale für gesundheitliche Aufklärung (BZgA) im Bereich der Gesundheitsförderung/ Prävention.

The "market" of institutions, organizations, and providers offering information in the field of health promotion and prevention is heterogeneous and complex. Reliable data and improvements in transparency and quality assurance are urgently needed at the national level. The Federal Center for Health Education (FCHE) organizes qualified nationwide surveys on available health-promoting services. The results are published as online databases with convenient options for data recall, which encourages information transfer and networking. The databases also facilitate analyses of supply and development of quality criteria. This contribution demonstrates the basics of FCHE activities in this field and presents three database examples.

Isolated elevation of serum alkaline phosphatase level in an uncomplicated pregnancy: a case report.

Serum level of alkaline phosphatase of placental origin was increased >10-fold in a 28-year-old pregnant woman. Repeated abdominal ultrasonographic scans yielded negative results for hepatobiliary disease. After delivery of a healthy baby, the placenta showed no major pathologic characteristics, and the alkaline phosphatase level returned to the reference range.

[The plasma level of kanamycin after intravenous and intramuscular injections in horses]. / Untersuchung der Plasmaspiegel von Kanamycin nach intravenöser und intramuskulärer Injektion bei Pferden.

A therapeutical dose of kanamycin was tested intravenously and intramuscularly in four normal standardbreds and plasma concentrations were measured over a 12 hour period. Plasma levels exceeded a minimum inhibitory concentration of 4 micrograms/ml within only 15 minutes for 8 hours both after i.v. and i.m. injection. Kanamycin revealed a mean plasma half life of 2.3 hours. Bioavailability of an intramuscular dose was about 76%. The pharmacokinetic parameters demonstrate the rapid onset of antibacterial plasma levels of the test compound. A dose regimen for horses of two times daily 5 mg/kg body weight ensures therapeutically effective plasma levels. The risk of accumulation as well as nephro- or ototoxic side effects are negligible at short-term treatment.

The consequences of nitrofurantoin-induced oxidative stress in isolated rat hepatocytes: evaluation of pathobiochemical alterations.

Oxidative stress was induced in isolated rat hepatocytes by incubation with nitrofurantoin in the absence and presence of the GSSG reductase inhibitor BCNU. In both cases nitrofurantoin markedly reduced glutathione but exerted cytotoxicity as measured by LDH release and loss of intracellular potassium only in BCNU pretreated cells. The onset of cytotoxicity was accompanied by an increase of lipid peroxidation. Oxidation of protein thiols, however, could not be detected in the early phase of cell damage. The cytoprotective activity of N-acetyl-cysteine > dithiothreitol = deferoxamine revealed the substantial importance of glutathione for cellular defence and the sensitivity of not yet identified thiol-dependent targets of oxidative stress.

Semiquantitative aspects of mast cells in normal skin and in neurofibromas of neurofibromatosis types 1 and 5.

Mast cells are supported to influence the growth of neurofibromas, because some of their mediators may also act as growth factors. Accordingly, mast cell stabilizers are claimed to reduce proliferation and itching of neurofibromas. Therefore, we quantified the mast cells of 19 neurofibromas and compared them with normal skin. We saw a statistically significant increase in mast cells in neurofibromas versus normal skin. However, there is no correlation between the age of neurofibromatosis (NF) patients and mast cell density. In our study the density of mast cells in neurofibromas is also independent of NF type; age of neurofibroma and chronic ultraviolet exposure in contrast to normal skin. Different tumors of the same patient had similar mast cell counts.