A culture-based assessment of the microbiota of conventional and free-range chicken meat from Irish processing facilities

Chicken meat is the most popularly consumed meat worldwide, with free-range and ethically produced meat a growing market among consumers. However, poultry is frequently contaminated with spoilage microbes and zoonotic pathogens which impact the shelf-life and safety of the raw product, constituting a health risk to consumers. The free-range broiler microbiota is subject to various influences during rearing such as direct exposure to the external environment and wildlife which are not experienced during conventional rearing practices. Using culture-based microbiology approaches, this study aimed to determine whether there is a detectable difference in the microbiota from conventional and free-range broilers from selected Irish processing plants. This was done through analysis of the microbiological status of bone-in chicken thighs over the duration of the meat shelf-life. It was found that the shelf-life of these products was 10 days from arrival in the laboratory, with no statistically significant difference (P > 0.05) evident between free-range and conventionally raised chicken meat. A significant difference, however, was established in the presence of pathogenesis-associated genera in different meat processors. These results reinforce past findings which indicate that the processing environment and storage during shelf-life are key determinants of the microflora of chicken products reaching the consumer.

On farm interventions to minimise Campylobacter spp. contamination in chicken

1. This review explores current and proposed on-farm interventions and assess the potential of these interventions against Campylobacter spp. 2. Interventions such as vaccination, feed/water-additives and, most importantly, consistent biosecurity, exhibit potential for the effective control of this pathogen and its dissemination within the food chain. 3. Due to the extensive diversity in the Campylobacter spp. genome and surface-expressed proteins, vaccination of poultry is not yet regarded as a completely effective strategy. 4. The acidification of drinking water through the addition of organic acids has been reported to decrease the risk of Campylobacter spp. colonisation in broiler flocks. Whilst this treatment alone will not completely protect birds, use of water acidification in combination with in-feed measures to further reduce the level of Campylobacter spp. colonisation in poultry may be an option meriting further exploration. 5. The use of varied types of feed supplements to reduce the intestinal population and shedding rate of Campylobacter spp. in poultry is an area of growing interest in the poultry industry. Such supplements include pro - and pre-biotics, organic acids, bacteriocins and bacteriophage, which may be added to feed and water. 6. From the literature, it is clear that a distinct, albeit not unexpected, difference between the performance of in-feed interventions exists when examined in vitro compared to those determined in in vivo studies. It is much more likely that pooling some of the discussed approaches in the in-feed tool kit will provide an answer. 7. Whilst on-farm biosecurity is essential to maintain a healthy flock and reduce disease transmission, even the most stringent biosecurity measures may not have sufficient, consistent and predictable effects in controlling Campylobacter spp. Furthermore, the combination of varied dietary approaches and improved biosecurity measures may synergistically improve control.

Novel technetium (III)-Q complexes for functional imaging of multidrug resistance (MDR1) P-glycoprotein

Overexpression of the multidrug resistance (MDR1) P-glycoprotein (Pgp) correlates with cancer chemotherapeutic failure. Lipophilic cationic radiopharmaceuticals such as 99mTc-sestamibi, 99mTc-tetrofosmin and 99Tc-furifosmin (Tc-Q12) have been validated as transport substrates for the MDR1 Pgp and may enable functional imaging of the MDR phenotype in cancer by observing enhanced washout rates of the tracers in those tumor areas expressing Pgp. To further explore and optimize the Pgp recognition properties of Schiff base phosphine mixed-ligand complexes of the Tc-Q series of nonreducible (Tc(III) cations, a variety of Tc-Q complexes were synthesized and tested in vitro for recognition as transport substrates by the human MDR1 Pgp.

METHODS

Tracer assays with human drug-sensitive KB-3-1 epidermal carcinoma and MDR KB-8-5 cells expressing nonimmunodetectable and modest levels of MDR1 Pgp, respectively, were used to screen and pharmacologically characterize 37 novel 99mTc-Q analogs.

RESULTS

The ideal agent should have low nonspecific binding, high distinction in net uptake between drug-sensitive cells and MDR tumor cells, and high enhancement of uptake in resistant cells after treatment with an MDR modulator, indicating selective blockade of Pgp-mediated efflux of the radiotracer. Three analogs, trans-[5,5'-(1,2-ethanediyldiimino)bis(2-OEt-2-Me-4-penten-3 -one)]bis[dimethyl(3-OMe-1-propyl)phosphine]99mTc(III) (99mTc-Q63) and two trans-[bis(methyl-bis(3-OMe-1-propyl)phosphine)] analogs (99mTc-Q57 and 99mTc-Q58) displayed transport distinctions between drug-sensitive and MDR cell lines that were equal to or greater than all previously available agents. Cyclosporin A, an MDR modulator, had no significant effect in KB-3-1 cells for these 99mTc-complexes but enhanced tracer accumulations in KB-8-5 cells with IC50 values of approximately 1 microM. In contrast, the non-MDR agents methotrexate and cisplatin had no effect on accumulation of 99mTc-Q complexes and 99mTc-sestamibi in KB-8-5 cells.

CONCLUSION

Technetium-99m-Q57, 99mTc-Q58 and 99mTc-Q63 are avid transport substrates recognized by the human MDR1 Pgp, and have enhanced in vitro properties that may enable functional imaging of Pgp in vivo with improved signal-to-noise ratios and tissue contrast compared to currently available agents.

Tracers and contrast agents in cardiovascular imaging: present and future

This brief article addresses the current status and future potential of nuclear medicine, X-ray computed tomography (CT), ultrasound (US), and magnetic resonance (MR) imaging in the diagnosis of cardiovascular diseases. The currently perceived advantages and disadvantages, as well as the possible future roles, of each of the modalities with regard to the evaluation of coronary artery disease are delineated. The certain advent of MR and US myocardial contrast agents, combined with the inexorable pressures of health care reform, will alter the future usage patterns of all four modalities. Future debates about which modality should be used in which clinical situation will be based not on "anatomy vs function", nor on which specialty owns which "turf", but rather on the issues of cost effectiveness and patient outcomes.

C-reactive protein as an indicator of infection relapse in patients with abdominal sepsis

C-reactive protein (CRP) concentrations were monitored serially in 97 patients with abdominal sepsis to determine if differences in infection type or site would produce diagnostic or prognostic CRP level elevations. After surgery and abdominal infection, the average (+/- SD) CRP peak values were 21.2 +/- 9.0 mg/dL. The CRP values rose markedly with infection, rose further with surgery, and subsided to less than 10 mg/dL with cure. Persistent levels of more than 10 mg/dL indicated abscess formation or continued infection. The average normal value at complete tissue healing after resolution of infection was 1.2 mg/dL, which was not different from that for healthy volunteers. Analysis suggested that CRP concentrations were not predictive of the type, site, or severity of abdominal infection; however, since persistent elevations were frequently associated with new or unresolved bacterial infection, serial determinations may be helpful in monitoring the course of disease and response to treatment.