Alternaria brassicae produces a host-specific protein toxin from germinating spores on host leaves

Spore suspensions of Alternaria brassicae, the causal agent of gray leaf spot in Brassica plants, were incubated on the leaves of cabbage (B. oleracea) and spore germination fluid (SGF) was collected after 48 h. A high molecular weight (HMW) fraction (>10 kDa) was separated from the SGF by ultrafiltration. In a detached leaf assay, the HMW fraction induced visible symptoms only on host leaves and the toxicity was lost by treatment with proteinase K or heat at 60 degrees C for 15 min, indicating the presence of host-specific protein toxin(s). A protein toxin in the HMW fraction was purified by several chromatography steps. The toxin induced water-soaked symptoms followed by chlorosis at concentrations of 0.5 to 1 microg/ml on host leaves, but not on nonhost leaves even at 50 microg/ml. The toxin also had infection-inducing activity when added to spore suspension of a nonpathogenic isolate of A. alternata, causing symptoms similar to the infection of A. brassicae only on host leaves. These results indicate that a new host-specific protein toxin named ABR-toxin is released from germinating spores of A. brassicae on host leaves. ABR-toxin migrated as a protein of 27.5 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point of ABR-toxin was estimated to be approximately 7.0 and 21 N-terminal amino acid residues were sequenced.

Assessment of patients with intellectual disability using the International Classification of Functioning, Disability and Health to evaluate dental treatment tolerability

BACKGROUND

Patients with serious intellectual disability (ID) are occasionally unable to tolerate dental treatment when intravenous sedation or general anaesthesia (IVS/GA) is involved. In order to make a decision regarding the application of IVS/GA, the International Classification of Functioning, Disability and Health (ICF) is useful. Therefore, in this study, a set of codes involved in dental problems were chosen from the ICF, and patients with ID who could tolerate dental treatments were compared with those who could not.

METHODS

From preliminary interviews of six patients with ID, 16 codes were chosen, and an objective five-rank scale was then constructed for use with all chosen codes. Forty-nine ID patients who visited the Okayama University Hospital for dental treatment between January and April 2003 were evaluated. Facility workers were interviewed according to the code set chosen. The participants were then divided into two subgroups depending on their tolerability of dental treatment. The results of these groups for all 16 codes were then compared.

RESULTS

Of the 49 patients interviewed, 23 were able to tolerate the dental treatment. In the 'Activities & Participation' section of the ICF, the tolerable group showed lower disability levels with regard to d110 Watching, d540 Dressing and d550 Eating. In other sections, there were no significant differences between the groups. The code set chosen in this study and the five-rank scales in each code were useful as they enabled easy interviewing.

CONCLUSIONS

The ICF was raised as a possibility for considering the application of IVS/GA for dental treatment on patients with ID. For clinical use of the ICF, it is recommended that significant codes should be selected and that the five-rank scale is used so that more objective results are obtained from interviews.

Intravenous sedation for dental patients with intellectual disability

BACKGROUND

The poor quality of oral health care for people with intellectual disability (ID) has been recognized, and the strong fears about dental treatment suggested as a major reason for disturbances of visits to dentists by such patients. Intravenous sedation is a useful method for relieving the anxiety and fear of such patients about dental treatment, and is frequently essential for ID patients undergoing dental treatment. However, decision regarding the dose of sedative required to be administered for an adequate level of sedation is difficult because the effect of sedation cannot be adequately assessed in patients with severe ID. As an appropriate sedative dose for dental patients with ID has not been fully established, we investigated sedative doses required and the effect of sedation in patients with ID, compared with other dental patients.

METHODS

We reviewed the anaesthetic records of dental patients with ID (73 cases) and other dental patients (19 cases) aged between 20 and 29 years who had undergone intravenous sedation with midazolam and propofol in Okayama University Dental Hospital, from January 2000 to December 2000. Intravenous sedation was induced with a bolus intravenous administration of midazolam (2-3 mg) and maintained with a continuous infusion of propofol. The dose of propofol was titrated to achieve an adequate level of sedation: asleep but responding to painful stimulation. The efficacy of sedation, the required doses of propofol, and the wake-up times were investigated for all subjects. The efficacy of sedation was evaluated by judging whether the patient became cooperative and allowed the dental treatment to be carried out or not. The complications induced by intravenous sedation were also evaluated in each subject. Differences in variables between subjects with ID and other subjects were analysed using the Mann-Whitney U-test.

RESULTS

Intravenous sedation was effective for dental treatment in all subjects with or without ID. The required dose of propofol in subjects with ID was 4.74 mg/kg/h (2.63-10.33 mg/kg/h), significantly higher than that required for other subjects (3.31, 1.72-4.80 mg/kg/h). Wake-up times of subjects with ID were similar to those of the other subjects. Severe complications were not seen during or after intravenous sedation.

CONCLUSION

The results of this study show that intravenous sedation is a useful method for dental patients with ID as well as for other dental patients, but indicate that dental patients with ID need higher doses of sedative to obtain an adequate level of sedation.

Amicrobial pustular dermatosis in two patients with immunological abnormalities

We report two patients with severe amicrobial pustular dermatosis with immunological abnormalities: a 63-year-old woman with a 30-year-history of discoid lupus erythematosus and sicca syndrome, and a 35-year-old woman with high levels of gamma-globulinemia and positive antinuclear antibodies. Both patients presented with crusty and eroded erythematous plaques studded with aseptic pustules on the back, face, and scalp. Histological examination showed acanthosis, neutrophilic exocytosis to the epidermis, and neutrophilic and lymphocytic infiltration with nuclear dust in the dermis. These patients were diagnosed as having "amicrobial pustulosis associated with autoimmune diseases". The eruptions improved with combination treatment of oral prednisolone with cyclosporin A or diaminodiphenylsulphone. Although the pathogenesis remains unclear, amicrobial pustular dermatosis might be one of the cutaneous complications in autoimmune diseases.