In situ saphenous vein bypass grafts: angiographic evaluation and interventional repair of complications

In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.     

Heightened vulnerability and increased risk-taking among adolescent chat room users: results from a statewide school survey.

PURPOSE: To profile adolescent Internet chat room users in terms of demographic characteristics, psychological and environmental factors, and behavioral risk factors. METHODS: The study sample was drawn from respondents to an anonymous statewide survey of 50,168 9th-grade public school students and included 40,376 students who reported Internet access at home and 19,511 who accessed chat rooms. Data were collected by the Minnesota Student Survey (MSS), a survey that has been administered triennially by the state's education department to public school students in grades 6, 9, and 12 since 1989. The MSS includes more than 117 questions (300 variables) addressing attitudinal, behavioral, and environmental issues. Data analysis consisted of comparing the odds of a particular characteristic or behavior for chat room users with that of nonusers. Analyses were run separately for boys and girls. The homogeneity of odd ratios was tested with the Breslow-Day statistic using SPSS for Windows. RESULTS: For boys and girls, use of Internet chat rooms was associated with psychological distress, a difficult living environment, and a higher likelihood of risky behaviors. Although most chat room users did not report serious problems, this group included a disproportionate number of troubled individuals. CONCLUSIONS: Because chat room use serves as an indicator of heightened vulnerability and risk-taking, parents and others need to be aware of potential dangers posed by online contact between strangers and youth.     

The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity

The integrity of sperm DNA is crucial for the maintenance of genetic health. A major source of damage is reactive oxygen species (ROS) generation; therefore, antioxidants may afford protection to sperm DNA. The objectives of the study were, first, to measure the effects of antioxidant supplementation in vitro on endogenous DNA damage in spermatozoa using the single cell gel electrophoresis (comet) assay and, second, to assess the effect of antioxidant supplementation given prior to X-ray irradiation on induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll centrifugation in the presence of ascorbic acid (300, 600 microM), alpha tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5, 10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand breakage was measured using the comet assay. Sperm DNA was protected from DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60 microM) and urate (400 microM). These antioxidants provided protection from subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or ascorbate and alpha tocopherol together induced further DNA damage. Supplementation in vitro with the antioxidants ascorbate, urate and alpha tocopherol separately has beneficial effects for sperm DNA integrity.      

Comparison of a blood-free medium and a filtration technique for the isolation of Campylobacter spp. from diarrhoeal stools of hospitalised patients in central Australia.

Single specimens of diarrhoeal stool from 676 patients, mostly aboriginals aged less than 5 years, admitted to Alice Springs Hospital, central Australia, for diarrhoea between Sept. 1988 and Feb. 1989, were examined for Campylobacter spp. by culture on a blood-free medium with selective supplement (BFM; Oxoid) and blood agar overlaid with a membrane filter (FM). Campylobacter spp. were isolated on either BFM or FM or both from 225 patients. Campylobacter spp. were isolated on BFM alone from 75 patients and on FM alone from 213 patients (p less than 0.001; chi 2 test). Most campylobacters isolated on BFM were C. jejuni. All C. jejuni subsp. doylei, all "C. upsaliensis" except one, all C. laridis, C. fetus subsp. fetus and several uncharacterised Campylobacter isolates were isolated on FM only. C. jejuni was isolated on BFM but not FM from several patients, and vice versa. Serotyping of C. jejuni and C. coli isolated from both media showed the serotypes recovered from the two media to be different in some patients. In some patients concurrent infection with several species or serotypes (up to five) of Campylobacter, or both, was shown for the first time by the use of FM. We conclude that the use in combination of a selective medium and a non-selective medium with a filtration technique are better than either medium alone for the isolation of Campylobacter spp.