Biogeography of Phallusia nigra: is it really black and white?

Ascidians (Chordata, Tunicata) are an important group for the study of invasive species biology due to rapid generation times, potential for biofouling, and role as filter feeders in an ecosystem. Phallusia nigra is a putative cosmopolitan ascidian that has been described as introduced or invasive in a number of regions in the Indo-Pacific Ocean (India, Japan, and Hawaii) and in the Mediterranean. The taxonomic description of P.

The influence of a TNF gene polymorphism on the severity of rheumatoid arthritis in the Brazilian Amazon.

Purpose: The aim of this study was to investigate the influence of the TNF -308 G/A polymorphism in the promoter region of the tumor necrosis factor-α gene on the susceptibility and severity of rheumatoid arthritis (RA) in individuals from the Brazilian Amazon.

Methods: A total of 323 individuals-192 healthy controls without arthritis and 131 individuals suffering from arthritis-were genotyped for this polymorphism using a methodology based on PCR-RFLP.

Results: The frequency of the A allele (TNF2) in rheumatoid arthritis sufferers was not significantly higher than in the controls (p=0.