A systematic review of compression treatment for venous leg ulcers.

OBJECTIVE: To estimate the clinical and cost effectiveness of compression systems for treating venous leg ulcers. METHODS: Systematic review of research. Search of 19 electronic databases including Medline, CINAHL, and Embase. Relevant journals and conference proceedings were hand searched and experts were consulted. MAIN OUTCOME MEASURES: Rate of healing and proportion of ulcers healed within a time period. STUDY SELECTION: Randomised controlled trials, published or unpublished, with no restriction on date or language, that evaluated compression as a treatment for venous leg ulcers. RESULTS: 24 randomised controlled trials were included in the review. The research evidence was quite weak: many trials had inadequate sample size and generally poor methodology. Compression seems to increase healing rates. Various high compression regimens are more effective than low compression. Few trials have compared the effectiveness of different high compression systems. CONCLUSIONS: Compression systems improve the healing of venous leg ulcers and should be used routinely in uncomplicated venous ulcers. Insufficient reliable evidence exists to indicate which system is the most effective. More good quality randomised controlled trials in association with economic evaluations are needed, to ascertain the most cost effective system for treating venous leg ulcers.     

Genetics of Streptomyces rimosus, the oxytetracycline producer.

From a genetic standpoint, Streptomyces rimosus is arguably the best-characterized industrial streptomycete as the producer of oxytetracycline and other tetracycline antibiotics. Although resistance to these antibiotics has reduced their clinical use in recent years, tetracyclines have an increasing role in the treatment of emerging infections and noninfective diseases. Procedures for in vivo and in vitro genetic manipulations in S. rimosus have been developed since the 1950s and applied to study the genetic instability of S. rimosus strains and for the molecular cloning and characterization of genes involved in oxytetracycline biosynthesis. Recent advances in the methodology of genome sequencing bring the realistic prospect of obtaining the genome sequence of S. rimosus in the near term.     

Relative Resistance of Four Peach Rootstocks to Phytophthora cactorum and Phytophthora megasperma

Shoot samples of four peach rootstocks that are important to the peach industry in Greece: KID I, GF305, GF677, and PR204, were inoculated with Phytophthora cactorum and Phytophthora megasperma in the field and in the glasshouse and were then evaluated with regard to susceptibility. The pathogenicity of P. cactorum and P. megasperma to peach rootstocks was confirmed with an excised twig assay. The peach rootstocks showed differential susceptibility to P. cactorum . GF305 was the least susceptible and KID I was the most susceptible, which suggests that the latter rootstock is unsuitable for orchards in which the conditions are favourable for Phytophthora diseases. GF677 and PR204 were moderately susceptible. The plants that were inoculated with P. megasperma in the field and in the glasshouse showed no sign of infection whereas twigs inoculated in vitro with P. megasperma developed necrosis. GF305 was the most resistant, KID I was the most susceptible and PR204 and GF677 were moderately resistant. The present results demonstrate that none of the four peach rootstocks used in this study was completely resistant to P. cactorum , particularly when rootstocks were flooded periodically to enhance disease development. Therefore an integrated approach including host and resistance cultural practices is recommended to manage diseases caused by P. cactorum in peach orchards in Greece.     

Temperature-sensitive mutants of the Streptomyces plasmid pIJ702

DNA from the Streptomyces plasmid pIJ702 was mutagenized in vitro using hydroxylamine and transformed into Streptomyces lividans. One plasmid with temperature-sensitive replication (pMT660) and one plasmid with a temperature-sensitive tyrosinase (pMT661) were isolated. The plasmid pMT661 contains a novel PstI restriction endonuclease site within the tyrosinase gene.     

Comparison between emission and transmission computed tomography of the liver.

Emission computed tomography (emission CT) and conventional planar gamma-camera imaging of the liver were compared in 242 patients with suspected metastatic spread to liver. Concordant data were obtained in 171 patients (71%). Single large lesions, multiple small lesions, and diffuse disease were accurately defined with this new radionuclide tomographic technique. The smallest lesion detected by emission CT was 8 mm. Emission CT, planar gamma-camera imaging, and transmission (x-ray) CT were compared in 107 patients. All three methods gave identical results in 76 patients (71%). Assessed against other criteria, such as histological findings and follow-up data, emission CT yielded the highest range of accuracy (92-96%), while transmission CT and planar gamma-camera imaging had similar but lower accuracies (78-81%). Emission CT had a false-positive rate of 2.8% and a false-negative rate of less than 1%. Thus emission CT is highly sensitive in detecting space-occupying disease in the liver.     

DNA amplification and an unstable arginine gene in Streptomyces lividans 66

Summary Streptomyces lividans 66 produced spontaneous chloramphenicol-sensitive mutants (Cml^s) at a frequency of about 1% of spores. The Cml^s mutant strains were very unstable, giving Arg^- mutants at frequencies of about 25% of spores. All the Arg^- mutants had amplified a particular 5.75 kb DNA fragment into tandem repeats of 250–500 copies per chromosome.     

Liver Transplantation in Man—III,Studies of Liver Function,Histology, and Immunosuppressive Therapy

The experience gained from 13 hepatic transplant operations is described, with particular reference to the findings in nine patients who survived the immediate operative period. A major problem was found to be infection. Fulminant pneumonia caused death in two adults, at a time when liver function was virtually normal. Infection related to bile fistula and sepsis may be overcome by an improved method of biliary drainage by cholecyst-dochostomy, which was carried out in the last two patients. Jaundice in the second week due to rejection was observed in several patients. The striking histological change was centrilobular cholestasis. The jaundice, which was not prevented by administration of antilymphocyte globulin, was rapidly controlled by temporarily increasing die dose of prednisone. One patient who survived for four and a half months and who had a poor tissue match subsequently developed chronic rejection with progressive cholestatic jaundice. Five of the patients were able to go home and at time of publication two are alive and well 14 and 20 weeks after treatment.     

Factors affecting the kinetics of progeny formation with F′lac in Escherichia coli K12

In matings of F′lac donors with an excess of recipient cells, different donor cells mated at different times. The concentration dependence of mating is incompatible with bimolecular reaction kinetics. In exponentially growing cultures, F′lac transfer from each donor cell continues to occur about once per generation. The establishment of F′lac in some recipient cells may take more than five generations.