A novel combination of plant growth regulators for in vitro regeneration of complete plantlets of guar [Cyamopsis tetragonoloba (L.) Taub.].

A novel combination of plant growth regulators comprising indole-3-butyric acid (IBA), 6-benzylaminopurine (BA) and gibberellic acid (GA3) in Murashige and Skoog basal medium has been formulated for in vitro induction of both shoot and root in one culture using cotyledonary node explants of guar, (Cyamopsis tetragonoloba). Highest percentages of shoot (92%) and root (80%) induction were obtained in the medium containing (mg/L) 2 IBA, 3 BA and 1 GA3. Shoot regeneration from the cotyledonary node explants was observed after 10-15 days. Regeneration of roots from these shoots occurred after 20 to 25 days. The regenerated plantlets showed successful acclimatization on transfer to soil. This protocol is expected to be helpful in carrying out various in vitro manipulations in this economically and industrially important legume.

Characterization of biofilm formed on intrauterine devices.

PURPOSE: Intrauterine device (IUD) is one of the most convenient contraceptive procedures used by women of Asian and African countries. Previous surveys have revealed that 75% of the IUDs recovered from patients suffering from reproductive tract infections (RTIs) were covered with a consortium of microbes. This study was designed to characterize these microbes and recommend remedial measures. METHODS: Quantitative measurement of biofilm formation was assessed by a microtitre plate assay on 86 samples of microorganisms dislodged from IUDs of patients with RTIs. Susceptibility of biofilm to various antimicrobial agents was also quantified. Scanning electron microscopy (SEM) was used to scrutinize the microorganisms adherent to IUDs. RESULTS: The organisms associated with IUDs were predominantly composed of Staphylococcus aureus (16%), Staphylococcus epidermidis (18%), Pseudomonas aeruginosa (5%), Escherichia coli (27%), Neisseria gonorrhoeae (2%), Candida albicans (20%) and Candida dubliniesis (12%). SEM studies indicated that these organisms were organized into biofilms. Studies on the in vitro adherence pattern by crystal violet staining on 96 well microtitre plates revealed that the biofilms were stably established after 60 hours. These biofilms are resistant to an array of antibiotics tested. CONCLUSION: Biofilm formation may be one of the major causes for persistent infection and antibiotic resistance in IUD users.

Serological investigation of refractory human adult periodontitis.

This study examined the difference between the serum antibody profiles in refractory adult periodontitis patients (group A), and compared to those (group B) who responded well to conventional periodontal treatment. The levels of specific IgG antibody to Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, Fusibacteriumnucleatum, and Eikenella corrodens were assessed in a group of 19 patients (group A) and 11 patients (group B). Specific IgG serum antibody levels were estimated using biotin-avidin linked immunosorbent assay (BALISA). Results indicated that Actinobacillus actinomycetemcomitans, and Bacteroides gingivalis had very high levels of specific circulating antibody in the sera of both groups of patients; whereas, Fusobacterium nucleatum and Eikenella corrodens showed considerable lower levels of antibody than the other two antigens. However, the differences between the two groups with regard to the antibody levels against different bacterial antigens were not statistically significant.