A prospective, controlled, double-blind, cross-over study of tripterygium wilfodii hook F in treatment of rheumatoid arthritis

A polyglycosides of Tripterygium wilfodii hook F (TWH) preparation with a code name of T2 is used in the present double-blind, controlled, cross-over study on the treatment of 70 cases of rheumatoid arthritis (RA). An impressive curative effect of T2 is confirmed much more convincingly by the present study than that by the previously reported clinical open trials. The adverse reactions and the probable pharmacological mechanism of T2 are also discussed.

Nucleotide sequences involved in the neolysogenic insertion of filamentous phage Cf16-v1 into the Xanthomonas campestris pv. citri chromosome

Following a protracted carrier state in the infected cell, filamentous bacteriophage Cf16-v1 neolysogenizes Xanthomonas campestris pv. citri by inserting the phage genome into the host chromosome. The integration region in the phage and the host chromosome, respectively, and the two junctions in the lysogen chromosome were isolated and their nucleotide sequence was determined. The phage and host attachment sites shared an identical 15-bp "core," 5'-TATACATTATGCGAA-3'. Located on either side of each core were two unique arm sequences. Each of the two phage-host junctions contained an intact core flanked by a hybrid combination of phage and host arm sequences. A 10-bp symmetrical sequence arranged as inverted repeats with 1-bp spacing straddled the core sequence. A 10-bp repeated sequence, 5'-GCGCTATGGC-3', was found distal to the core in opposite orientation at the phage attachment site, while an abbreviated form of this sequence was present in the host attachment site. These sequence characteristics indicate that neolysogenic insertion of Cf16-v1 was accomplished by a site-specific recombination mechanism similar to lambda integration. However, in contrast to lambda, the phage and the host attachment sites in the Cf16-v1 system contained a high G + C nucleotide bias (except for the core sequence itself).

Transformation of psi- Saccharomyces cerevisiae to psi+ with DNA co-purified with 3 micron circles

DNA enriched for supercoiled plasmids prepared from the 3 micron plasmid-enriched, [psi+], [2 micron degrees] strain 6-1G-P188 and from the [2 micron+] [psi+] strain LL20 can be used to transform a psi- recipient strain to psi+. Fractionation of the former preparation by electrophoresis showed that the 3 micron plasmid band contained the transforming activity.

[Transfer of plasmid RP4 into some phytopathogenic bacteria and its relation to their virulence]

Plasmid RP4 were transferred from Escherichia coli into Pseudomonas solanacerum, Xanthomonas campestris pv. oryzae, X. campestris pv. campestris, and X. campestris pv. citri at the frequencies of 1.8 X 10(-6), 2.8 X 10(-6), 1.4 X 10(-2) and 2.0 X 10(-3), respectively. The frequencies of transfer depended on bacterial species and conjugation conditions. Treatment of bromide at the concentration of 2 micrograms/ml and acridine orange at 100 micrograms/ml for 32 hrs the plasmid RP4 could be cured from the transconjugant of P. solanacerum at the frequencies of 75% and 95%, respectively. When transconjugant of P. solanacearum was inoculated into tomato plants, the decrease in virulence was observed, furthermore, no plasmids were detected both in the wild-type strain and the cured transconjugant. It thus appears that the virulence may not be related to plasmids.