Isolation of Streptococcus suis from 2 lambs with a history of lameness.

Streptococcus suis was isolated postmortem from 2 lambs with a history of lameness. Identity of S. suis was confirmed by species-specific polymerase chain reaction (PCR) and by 16S rRNA gene sequencing. One isolate was untypable by serotyping and non-encapsulated, while the other isolate was serotype 33. The lambs had come from the same farm, and there was no evidence of contact between the lambs and pigs. Although the natural niche for S. suis is considered to be the pig, a wide range of host species may be affected by this pathogen.

Isolement deStreptococcus suischez 2 agneaux avec une anamnèse de boiterie.Streptococcus suis a été isolé post-mortem chez 2 agneaux avec une anamnèse de boiterie. L'identité de S. suis a été confirmée par une amplification en chaîne par la polymérase (ACP) et par le séquençage génétique de l'ARNr 16S. Un isolat n'a pas pu être typé par sérotypage et était non encapsulé, tandis que l'autre isolat était de sérotype 33. Les agneaux provenaient de la même ferme et il n'y avait aucune preuve de contact entre les agneaux et les porcs. Même si le créneau naturel de S. suis est considéré comme étant le porc, un vaste éventail d'espèces hôtes peuvent être affectées par cet agent pathogène.(Traduit par Isabelle Vallières).

The transcription factor Sry-related HMG box-4 (SOX4) is required for normal renal development in vivo.

BACKGROUND: The DNA-binding transcription factor Wilms' Tumor Suppressor-1 (WT1) plays an essential role in nephron progenitor differentiation during renal development. We previously used Wt1 chromatin-immunoprecipitation coupled to microarray (ChIP-chip) to identify novel Wt1 target genes that may regulate nephrogenesis in vivo. We discovered that all three members of the SoxC subfamily, namely, Sox4, Sox11, and Sox12, are bound by Wt1 in mouse embryonic kidneys in vivo. SoxC genes play master roles in determining neuronal and mesenchymal progenitor cell fate in a multitude of developmental processes, but their function in the developing kidney is largely unknown. RESULTS: Here we show that all three SoxC genes are expressed in the nephrogenic lineages during renal development. Conditional ablation of Sox4 in nephron progenitors and their cellular descendants (Sox4(nephron-) mice) results in a significant reduction in nephron endowment. By postnatal day (P)7, Sox4(nephron-) renal corpuscles exhibit reduced numbers of Wt1+ podocytes together with loss of expression of the slit diaphragm protein nephrin. Sox4(nephron-) mice develop early-onset proteinacious glomerular injury within 2 weeks of birth progressing to end-stage renal failure within 5-9 months. CONCLUSIONS: Collectively, our results demonstrate an essential requirement of Sox4 for normal renal development in vivo.

Effect of 2-amino-9H-pyrido[2,3-b]indole (AalphaC), a carcinogenic heterocyclic amine present in food, on atherosclerotic plaque development in apoE deficient mice.

There is experimental and epidemiological evidence demonstrating that polycyclic aromatic hydrocarbons (PAHs) are involved in the pathogenesis of cardiovascular diseases. However, heterocyclic amines (HAs), a class of carcinogenic compounds present in food, which share many biochemical features with PAHs, have not received much attention. Previous reports have shown that the heterocyclic amine 2-amino-9H-pyrido[2,3-b]indole (AalphaC) binds and metabolically affects endothelial cells in animal models suggesting a potential role in vascular remodeling. The present study investigates the effect of exposure to HAs on atherosclerotic plaque development in the apoE(-/-) mice. We observed that animals treated with AalphaC developed atherosclerotic lesions characterized by lower lipid content but richer in inflammatory cells and collagen content when compared with control animals. Moreover, atherosclerotic plaques from AalphaC-treated apoE(-/-) mice were also smaller with a marked reduction in the tunica media thickness. Furthermore, total cholesterol levels were significantly reduced in AalphaC-treated apoE(-/-) mice. In contrast to what has been previously reported for PAHs, we provide for the first time evidence that HAs may protect against cardiovascular disease by inducing stable atherosclerotic plaques and reducing circulating cholesterol levels. These results open new avenues to further investigate the role of these food-borne carcinogens in cardiovascular physiology and pathology.