Influence and variation of the body mass index in patients treated with etanercept for plaque-type psoriasis.

A relationship between psoriasis, pro-inflammatory cytokines and obesity has been demonstrated. Tumour necrosis factor-alpha (TNF-alpha), that is involved in the pathogenesis of psoriasis, is commonly over-expressed in obese subjects, and seems to be derived from inflammatory cells and adipocytes. The primary aim of this study is to investigate whether the Body Mass Index (BMI) of patients influences the clinical response to etanercept, a competitive inhibitor of TNF-alpha approved for the treatment of moderate-to-severe plaque-type psoriasis. The secondary aim is to evaluate whether the TNF-alpha inhibition influences the weight and BMI profile of patients. One hundred patients received 50 mg etanercept twice weekly for 12 weeks, followed by 25 mg. At weeks-12 and 24, treatment efficacy and tolerability were evaluated, as well as body weight and BMI. BMI values did not correlate with etanercept efficacy. Mean PASI score variation did not show significant differences among the BMI groups. A statistically significant weight gain and BMI variation were observed in a consistent rate of patients. Patient BMI does not influence psoriasis efficacy parameters. Although the role of anti TNF-alpha molecules on weight regulation need to be confirmed, our study shows that etanercept treatment may induce weight gain and a BMI increase.

Nucleotide sequence of the gene encoding the nitrogenase iron protein (nifH) of Azospirillum brasilense and identification of a region controlling nifH transcription.

The DNA sequence was determined for the Azospirillum brasilense nifH gene and part of the nifD gene. The nifH gene is 885 bp long and encodes 293 amino acid residues. The region upstream of the nifH open reading frame contains a putative promoter whose sequence shows perfect homology with promoters of other diazotrophic bacteria and two putative upstream activator sequences. Experiments with the promoter-probe vector pAF300 showed that this region promotes transcription in response to the nitrogen and oxygen availability of the cell. The amino acid sequence was deduced from the DNA nucleotide sequence of nifH; the polypeptide contains the four cysteine residues highly conserved among other nifH products and an arginine residue at position 101 which could be the site of the modification occurring during the "switch-off" of nitrogenase. The codon usage appears to be very biased reflecting the high G + C content of the Azospirillum nifH gene. In a comparison of the amino acid sequence with the other 18 known nifH gene products, the A. brasilense nifH product showed the highest level of homology with fast-growing Rhizobia suggesting interesting evolutionary implications.

Cloning of histidine genes of Azospirillum brasilense: organization of the ABFH gene cluster and nucleotide sequence of the hisB gene.

A cluster of four Azospirillum brasilense histidine biosynthetic genes, hisA, hisB, hisF and hisH, was identified on a 4.5 kb DNA fragment and its organization studied by complementation analysis of Escherichia coli mutations and nucleotide sequence. The nucleotide sequence of a 1.3 kb fragment that complemented the E. coli hisB mutation was determined and an ORF of 624 nucleotides which can code for a protein of 207 amino acids was identified. A significant base sequence homology with the carboxy-terminal moiety of the E. coli hisB gene (0.53) and the Saccharomyces cerevisiae HIS3 gene (0.44), coding for an imidazole glycerolphosphate dehydratase activity was found. The amino acid sequence and composition, the hydropathic profile and the predicted secondary structures of the yeast, E. coli and A. brasilense proteins were compared. The significance of the data presented is discussed.