Comparison of microbial composition in the subgingival plaque of adult crowded versus non-crowded dental regions.

It has been reported in the literature that certain species of bacteria (periodontopathogens) present in the subgingival plaque are associated with destructive periodontal disease. The purpose of this study was to investigate and compare the presence and proportional distribution of periodontopathogens in the subgingival plaque of adult crowded versus non-crowded dental regions. Thirty adult patients with anterior dental crowding were selected from the Orthodontic Clinic of the University of Pennsylvania. After orthodontic records were taken and the periodontal examination was performed, subgingival plaque samples were collected from crowded (experimental) and contralateral non-crowded regions (control) of each patient. The presence of 9 periodontopathic species, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, Campylobacter rectus, Capnocytophaga species, Fusobacterium species, Peptostreptococcus micros, Porphyromonas gingivalis, and Bacteroides forsythus, was determined using culture and immunofluorescence techniques. The bacterial morphotype was also determined by the use of dark-field microscopy. It was found that supragingival plaque accumulation in crowded regions was significantly greater than in non-crowded regions. Analysis of the bacteria showed that the samples from crowded regions consistently contained more species of periodontopathogens than the samples from non-crowded regions. Morphologically, more spirochetes and motile rods were present in the crowded-region samples. In terms of the presence of individual periodontopathogens, Fusobacterium species, Capnocytophaga species, C rectus, and P micros were significantly more common in the crowded samples than in the non-crowded samples. It was concluded that: (1) more plaque accumulated in crowded areas; (2) more species of periodontopathogens were present in the subgingival plaque of crowded regions; (3) morphologically, more spirochetes and motile rods were present in crowded areas; and (4) Fusobacterium species, Capnocytophaga species, C rectus, and P micros were present more often in crowded areas than in non-crowded areas (P < 0.05).

Hereditary hemorrhagic macular dystrophy.

We treated two brothers who had a hemorrhagic macular lesion in one eye; a similar problem affected the fellow eye of both patients within eight months. Generalized fine granularity of the retinal pigment epithelium and peripheral iris transillumination defects were observed in both siblings. A study of the family suggested that the disorder was dominantly inherited and probably was Sorsby's pseudoinflammatory macular dystrophy. The macular lesions in one brother were treated by argon green laser photocoagulation and in the other brother by krypton red laser photocoagulation. Although the brother treated by krypton red laser photocoagulation attained better final visual function, additional differences in treatment methods also may have contributed to the final outcome.

Hepatitis B infection in ophthalmologists.

A seroepidemiologic survey of ophthalmologists in Western Pennsylvania was performed to define the hepatitis B virus (HBV) exposure risk for this subspecialty population. Of 70 participating ophthalmologists, only 5 (7.1%) had serologic evidence of prior hepatitis (positive hepatitis B surface antibody and antibody to the core antigen of hepatitis B). No participants were found to be HBsAg (hepatitis B surface antigen) positive. The infection rate for ophthalmologists appears lower than that previously described for physicians involved in surgical and nonsurgical medical specialties. However, caution is still recommended since hands and surgical instruments may become contaminated with HBV from the blood and secretions of hepatitis B patients or carriers.

Retinal toxicity of amphotericin B in vitrectomised versus non-vitrectomised eyes.

The retinal toxicity of intravitreally administered amphotericin B was compared in non-vitrectomised versus vitrectomised rabbit eyes. Doses of 5 and 10 micrograms in both groups resulted in transient vitritis but had no effect on electroretinograms. Histopathological examination four weeks after injection showed vitreous cells and minimal areas of retinal necrosis in both groups at 5 or 10 micrograms doses. At these doses vitrectomy did not modify the retinotoxic effects of intravitreally administered amphotericin B. At higher doses marked toxicity was found in both vitrectomised and non-vitrectomised groups.

Diffuse cutaneous hypersensitivity reaction after dexamethasone/polymyxin B/neomycin combination eyedrops.

Localized cutaneous hypersensitivity reactions to antibiotic eyedrops are not unusual. To our knowledge, however, a diffuse cutaneous reaction to eyedrops containing dexamethasone/polymyxin B/neomycin has never been reported. We describe the diffuse skin changes noted in a 72-year-old patient five days after starting eyedrop therapy.

The effect of doxorubicin on hepatic and cardiac glutathione.

The effect of the antitumor antibiotic doxorubicin on glutathione and glutathione disulfide levels in mouse heart and liver has been evaluated. The glutathione content of hepatic and cardiac tissue from saline-treated controls exhibited a statistically significant diurnal variation. Doxorubicin administration produced a dose-related decrease in hepatic glutathione which was not blocked by pretreatment with the free radical scavenger alpha-tocopherol; a lesser drop in cardiac glutathione was also documented. These changes may play an important role in the metabolism and toxicity of doxorubicin.