Expression of platelet-derived growth factor BB, erythropoietin and erythropoietin receptor in canine and feline osteosarcoma.

The discovery of expression of the erythropoietin receptor (EPO-R) on neoplastic cells has led to concerns about the safety of treating anaemic cancer patients with EPO. In addition to its endocrine function, the receptor may play a role in tumour progression through an autocrine mechanism. In this study, the expression of EPO, EPO-R and platelet-derived growth factor BB (PDGF-BB) was analysed in five feline and 13 canine osteosarcomas using immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR). EPO expression was positive in all tumours by IHC, but EPO mRNA was only detected in 38% of the canine and 40% of the feline samples. EPO-R was expressed in all samples by quantitative RT-PCR (RT-qPCR) and IHC. EPO-R mRNA was expressed at higher levels in all feline tumours, tumour cell lines, and kidney when compared to canine tissues. PDGF-BB expression was variable by IHC, but mRNA was detected in all samples. To assess the functionality of the EPO-R on tumour cells, the proliferation of canine and feline osteosarcoma cell lines was evaluated after EPO administration using an alamarBlue assay and Ki67 immunostaining. All primary cell lines responded to EPO treatment in at least one of the performed assays, but the effect on proliferation was very low indicating only a weak responsiveness of EPO-R. In conclusion, since EPO and its receptor are expressed by canine and feline osteosarcomas, an autocrine or paracrine tumour progression mechanism cannot be excluded, although in vitro data suggest a minimal role of EPO-R in osteosarcoma cell proliferation.

Immune response to Cystoisospora suis in piglets: local and systemic changes in T-cell subsets and selected mRNA transcripts in the small intestine.

Infections of neonatal piglets with Cystoisospora suis are responsible for substantial economic losses in pig production. To investigate kinetics of T-cell populations, which are possibly involved in this infection, lymphocytes from blood, spleen, mesenteric lymph nodes and the jejunal mucosa of infected and noninfected piglets were investigated by flow cytometry and immunohistochemistry at five time points during the acute phase of primary infection. Additionally, mRNA expression levels of pattern recognition receptors and immunomodulatory cytokines in the jejunum were investigated. T-cell receptor-γδ(+) T cells were found to be increased in the gut mucosa 4 days after infection and were most likely involved in the primary local immune response. Five to eleven days later, cytotoxic T cells peaked in this location, which was preceded by an expansion of this lymphocyte population in the mesenteric lymph nodes. In intestines of infected piglets, mRNA expressions of TLR-2, NOD2 and TNF-α were significantly upregulated, suggesting an involvement in parasite recognition, immune response and possibly also in immunopathology. Taken together, this study identifies cellular and molecular players involved in the early immune responses against C. suis, but their precise role in the pathogenesis and control of this neonatal disease requires further investigation.

[Local anesthesia after percutaneous application. II]. / Lokalansthesie nach percutaner Aufnahme. II. Mitteilung

Cyclohexane and hexadecane have been found to accelerate the penetration of local anesthetics (lidocaine, fomocaine, procaine) through the intact skin of guinea-pigs. Dissolved in cyclohexane, the potency of lidocaine is twice that of fomocaine, the latter being more active than procaine. When dissolved in hexadecane, the activity of the local anesthetics in markedly reduced. In combination with 2-butanone, (30% w/w), a solvent without any apparent effect on the permeability of skin, enhanced anesthetic effects are noted. The anesthetic bases, dissolved in dimethyl sulfoxide, produce a much deeper and longer local anesthetic effect than the solutions of their salts.