Phenotypic and genetic characterization of enteropathogenic Escherichia coli (EPEC) and entero-aggregative E. coli (EAEC) from diarrhoeal and non-diarrhoeal children in Libya

A total of 50 Escherichia coli strains isolated in a Libyan hospital (20 from children with diarrhoea and 30 from healthy children) were investigated for their pathotypes and virulence traits. Altogether nine eae-positive (enteropathogenic E. coli, EPEC) and nine aggR-positive (entero-aggregative E. coli, EAEC) strains were identified. Significantly (P=0.001) more EPEC strains were identified from diarrhoeal patients (n=8) than from healthy controls (n=1), while six EAEC strains were identified from diarrhoeal and three from healthy children. Typical (eae(+), EAF(+), bfp(+)) EPEC strains (n=6) belonged to classical EPEC serogroups O55, O114, O127 and showed localized adherence on Hela cells. EAEC strains revealed genetic heterogeneity but uniformly adhered to HeLa cultures in an entero-aggregative adherence pattern. Antibiotic resistance frequently, characterized the strains. Sixty-eight percentage of the strains were resistant against at least one antibiotic and 30% harbored a class 1 integron independently of their clinical background. This is the first report from North Africa demonstrating the significance of EPEC and EAEC.     

Fatal toxoplasmosis and concurrent Calodium hepaticum infection in Korean squirrels (Tanias sibericus)

Four Korean squirrels (Tanias siberius) imported in Spain from People's Republic of China died 2 days after their arrival at a pet shop. They had neurological signs associated with generalized toxoplasmosis involving brain, lungs, liver, and the heart. Toxoplasma gondii-like tachyzoites and tissue cysts were found in organs of all four squirrels. The protozoa stained positively with T. gondii polyclonal antibodies and were ultrastructurally similar to T. gondii. Calodium (Capillaria) hepaticum infection was found in the liver of one squirrel.     

Immunohistochemical expression of progesterone receptors, growth hormone and insulin growth factor-I in feline fibroadenomatous change

The immunohistochemical expression, tissue-specific and cell-specific distribution patterns of progesterone receptors (PR), growth hormone (GH) and insulin growth factor-I (IGF-I) have been studied in 22 cases of feline fibroadenomatous change (FFAC). PR and GH were detected in all cases and were distributed homogeneously throughout the lesion, while IGF-I was detected in 77% of the cases at the site of ductal budding. The simultaneous expression of PR, GH and IGF-I was detected in epithelial cells in 14 of 22 cases while PR and GH expression only was detected in epithelial cells in 11 cases. Cases that expressed GH and IGF-I without PR expression in the stroma were the most numerous. Double immunohistochemical staining showed the co-localisation of PR and GH in a subset of ductal epithelial cells located between basal/myoepithelial and luminal cells (probably undifferentiated stem cells). These results suggest that ligand-activated progesterone receptors may induce the local synthesis of GH which in turn may exert its proliferative action directly and also indirectly through the production of other growth factors, such as IGF-I, in an autocrine/paracrine manner.     

Pharmacokinetic-pharmacodynamic integration of orbifloxacin in rabbits after intravenous, subcutaneous and intramuscular administration

The single-dose disposition kinetics of orbifloxacin were determined in clinically normal rabbits (n=6) after intravenous (i.v.), subcutaneous (s.c.) and intramuscular (i.m.) administration of 5 mg/kg bodyweight. Orbifloxacin concentrations were determined by high performance liquid chromatography with fluorescence detection. Minimal inhibitory concentrations (MICs) assay of orbifloxacin against 30 strains of Staphylococcus aureus from several European countries was performed in order to compute pharmacodynamic surrogate markers. The concentration-time data were analysed by compartmental and noncompartmental kinetic methods. Steady-state volume of distribution (V(ss)) and total body clearance (Cl) of orbifloxacin after i.v. administration were estimated to be 1.71+/-0.38 L/kg and 0.91+/-0.20 L/h x kg, respectively. Following s.c. and i.m. administration orbifloxacin achieved maximum plasma concentrations of 2.95+/-0.82 and 3.24+/-1.33 mg/L at 0.67+/-0.20 and 0.65+/-0.12 h, respectively. The absolute bio-availabilities after s.c. and i.m. routes were 110.67+/-11.02% and 109.87+/-8.36%, respectively. Orbifloxacin showed a favourable pharmacokinetic profile in rabbits. However, on account of the low AUC/MIC and C(max)/MIC indices obtained, its use by i.m. and s.c. routes against the S. aureus strains assayed in this study cannot be recommended given the risk of selection of resistant populations.     

Effect of rooibos tea (Aspalathus linearis) on Japanese quail growth, egg production and plasma metabolites

1. Birds have been proposed as a suitable model for studies on ageing because of their long life in comparison with similar-sized mammals. However, some weak fliers, such as Galliformes, are the exception to this rule. The aim of the present study was to determine the effects of the treatment with rooibos tea (Aspalathus linearis), a natural source of flavonoid antioxidants and compounds with phyto-oestrogenic activity, on postnatal development and egg production of aged Japanese quail (Coturnix coturnix japonica). 2. Substitution of drinking water with traditional rooibos tea or diet supplementation with ground rooibos tea affected body weight of Japanese quail up to 100 d of age. The body weight of males drinking rooibos tea or eating rooibos-supplemented food decreased significantly. There was a trend toward increased body weight of tea drinking females and a significant increase in the body weight of hens fed the rooibos-supplemented diet. Although rooibos treatment did not significantly increase egg production in young hens, the decrease in egg production of rooibos-treated aged hens (360 d of age) was significantly reduced, regardless of the egg production levels (high - 80%; low - 20%) before the treatment. 3. The results suggest that treatment with rooibos tea positively affected body weight and egg production in quail hens and prolonged the productive period of aged animals. Further studies would be needed to address the question whether these effects are due to the antioxidant or phyto-oestrogenic activities of rooibos.     

Exposure to Sarcocystis spp. in horses from Spain determined by Western blot analysis using Sarcocystis neurona merozoites as heterologous antigen

Horses serve as an intermediate host for several species of Sarcocystis, all of which utilize canids as the definitive host. Sarcocystis spp. infection and formation of latent sarcocysts in horses often appears to be subclinical, but morbidity can occur, especially when the parasite burden is large. A serological survey was conducted to determine the presence of antibodies against Sarcocystis spp. in seemingly healthy horses from the Galicia region of Spain. Western blot analyses using Sarcocystis neurona merozoites as heterologous antigen suggested greater than 80% seroprevalance of Sarcocystis spp. in a sample set of 138 horses. The serum samples were further tested with enzyme-linked immunosorbent assays (ELISAs) based on recombinant S. neurona-specific surface antigens (rSnSAGs). As expected for horses from the Eastern Hemisphere, less than 4% of the serum samples were positive when analyzed with either the rSnSAG2 or the rSnSAG4/3 ELISAs. An additional 246 horses were tested using the rSnSAG2 ELISA, which revealed that less than 3% of the 384 samples were seropositive. Collectively, the results of this serologic study suggested that a large proportion of horses from this region of Spain are exposed to Sarcocystis spp. Furthermore, the anti-Sarcocystis seroreactivity in these European horses could be clearly distinguished from anti-S. neurona antibodies using the rSnSAG2 and rSnSAG4/3 ELISAs.