Chlamydia psittaci: growth characteristics and enumeration of serotypes 1 and 2 in cultured cells.

The growth characteristics of Chlamydia psittaci serotypes 1 and 2 (ovine and bovine origin) were studed in mouse L cells. Formation of inclusions and yield of infectious progeny for serotype 1 were maximal when host cells were treated with cycloheximide and the pH in the cell culture medium was 7.2-7.4. The number of cells that contained inclusions and the infectivity yield for serotype 2 were maximal when the pH was 6.6-7.0. Treatments with diethylaminoethyl dextran and cycloheximide increased inclusion formation in serotype 2 but decreased the yield per infected cell. For both serotypes, centrifugation of the chlamydiae onto monolayers infected 50-1,200 times the number of cells infected with use of stationary adsorption. An enumeration method for L-cell infectious units was developed that gave higher titers than the chicken embryo 50% lethal dose after yolk sac inoculation.     

Intratumor bacillus Calmette-Guerin therapy for chest wall recurrence of carcinoma of the breast.

Intratumor bacillus Calmette-Guerin administration is effective for treating chest wall recurrence from carcinoma of the breast in selected patients. Our results suggest that bacillus Calmette-Guerin therapy can be used alone, with systemic chemotherapy, hormonal therapy or in previously irradiated tissue. It represents local treatment for local disease that is well tolerated. Intratumor bacillus Calmette-Guerin treatment is a useful clinical method for the treatment of local chest wall disease.     

Effect of dietary selenium on the primary and secondary immune response in calves challenged with infectious bovine rhinotracheitis virus

The present study was conducted to determine if a selenium deficiency affects the primary and secondary humoral immune response of calves challenged with infectious bovine rhinotracheitis virus (IBRV) and to evaluate changes in glutathione peroxidase (GSH-Px) and creatine phosphokinase activities associated with selenium deficiency and viral stress. Treatments included 1) +Se (0.2 mg/kg diet) and 2) -Se (0.03 mg/kg diet). Calves were adapted to their assigned diets during an 84-d depletion period. By d 42 of the depletion period, whole-blood GSH-Px was lower for -Se calves than for +Se calves. Differences between treatments in plasma GSH-Px were observed by d 14. On d 84, Se-dependent GSH-Px activity in liver was higher in +Se calves. After depletion of -Se calves, animals in both treatments were intranasally inoculated with IBRV on d 0 and 35 of the 70-d challenge phase. Whole-blood and plasma GSH-Px increased after IBRV inoculation in +Se calves but not in Se-deficient calves. Serum IgM was higher for +Se calves throughout the challenge phase. Serum IgM increased in both treatments after primary IBRV inoculation but was unaffected by secondary challenge. Serum IgG was not affected by selenium status but increased in both treatments after secondary IBRV challenge. Serum IBRV antibody titers increased after inoculation on d 0 and 35. By d 49, IBRV antibody titers were higher for +Se calves than in Se-deficient calves. These results indicate that selenium deficiency may depress the immune response of calves challenged with a foreign pathogen.     

Laser balloon angioplasty: effect of exposure duration on shear strength of welded layers of postmortem human aorta

Laser Balloon Angioplasty (LBA) is a technique that may improve the results of balloon angioplasty by thermally sealing arterial dissections and reducing elastic recoil. To define the relationship between laser-exposure duration and the strength of thermal welds made between separated layers of arterial wall, 360 1-cm discs of human postmortem aorta were lased for six different exposure intervals at three different temperature ranges, comparing shear strength of thermal welds in the different groups. Twenty discs were lased to achieve plateau adventitial temperatures of 95 degrees C-104 degrees C (group A), 105 degrees C-114 degrees C (group B), or 115 degrees C-124 degrees C (group C) at each of the exposure periods (5, 10, 15, 20, 25, and 30 sec). A 400-micron fiberoptic coupled to a 1.06 micron continuous wave neodymium:YAG laser was placed perpendicularly 8 mm above the luminal surface of each disc, which had been split midway between the intimal and adventitial surface and reapposed. Mean laser energy ranged 78-378 J delivered in a decremental stepwise fashion to achieve quickly and maintain the target plateau tissue temperature. Mean weld strength increased in relation to both achieved tissue temperature and laser-exposure duration, with at least 10 sec necessary, at temperatures greater than 95 degrees C, for reliable thermal welding. Laser exposure for greater than 20 sec provided no statistical increment in weld strength. In the anticipated clinical performance of LBA, these data suggest that when thermal fusion of disrupted arterial tissues is desired, a laser-exposure duration of 10-20 sec is optimal.     

Dysplastic naevi in a population-based survey

The prevalence of dysplastic naevi was studied in a population-based survey of 380 30 to 39-year-old and 50 to 59-year-old non-Maoris in Milton, a small town in the south of New Zealand. Photographs of all pigmented naevi greater than or equal to 4 mm in diameter were taken during the survey and subsequently evaluated by two experienced reviewers. Nine percent of the group (95% CI, 6%-13%) were judged to have one or more dysplastic naevi. Interobserver agreement over the diagnosis of dysplastic naevi was 85% (kappa = 0.55). Dysplastic naevi were associated with higher counts of moles greater than or equal to 2 mm in diameter; 50 or more such moles increased the likelihood of having three or more dysplastic naevi about 40-fold. Naevi judged to be dysplastic were, therefore, relatively common and were associated with increased numbers of common moles.     

Context and content: the impact of school-leaving and school-based health education on AIDS-relevant cognitions.

A survey examined health beliefs and intentions among 690 16-18 year-olds in Dundee. Respondents in the younger cohort (n = 363) were classified according to their educational situation (at school vs left) and self-reports of having received AIDS/HIV-relevant health education. Both remaining in school and receiving AIDS/HIV-relevant health education had independent beneficial effects, but the effects of leaving school also interacted with sex of respondent and with amount of relevant education received prior to leaving. Males' and females' reliance on mass media and other information sources diverged once they left school, indicating that males who leave school early are most likely to disregard useful or important information regarding AIDS. Consistent with this finding, leaving school reduced the difference between males' and females' intention to use condoms with a new partner. The beneficial impact of having previously received AIDS/HIV-relevant education on beliefs concerning the controllability of the epidemic and on feeling worried about everyday contact with a person with HIV/AIDS, was most marked among those who had left school. The results are discussed in terms of their implications for health education strategies.