OSIRIS-REx Contamination Control Strategy and Implementation

OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This article describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and <180 ng/cm² of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication among scientists, engineers, managers, and technicians.

Etoposide, ifosfamide, and cisplatin in extensive small cell lung cancer

From December 1987 through April 1989, 40 patients with extensive-stage small cell carcinoma of the lung were enrolled in a Hoosier Oncology Group (HOG) trial using etoposide, ifosfamide, and cisplatin (VIP). Patients with extensive disease were eligible if they had not received prior chemotherapy, had a Karnofsky performance status of 50 or more, and had adequate renal function (creatinine, less than 1.5 mg/dl) and bone marrow reserve (granulocyte count, greater than or equal to 2500/microliters; platelets, greater than or equal to 125,000/microliters). Doses of therapy were: etoposide 75 mg/m2/day on days 1 to 5, ifosfamide 1.2 g/m2/day on days 1 to 5, and cisplatin 20 mg/m2/day on days 1 to 5. The first 11 patients received a 5-day course; this was repeated every 21 days for four cycles, but therapy was shortened to 4 days when unacceptable toxicity was noticed in these patients. Overall, 14 (37%) had a complete remission (overall response rate, 71.1%) with a median survival of 42 weeks (28 weeks on 5-day regimen and 45 weeks on 4-day regimen). There were five early deaths. Although toxic, VIP produces a high complete remission rate in patients with extensive disease and warrants further evaluation. A prospective randomized trial comparing cisplatin and etoposide to the VIP regimen is underway through HOG.

Random prospective study of vindesine versus vindesine plus high-dose cisplatin versus vindesine plus cisplatin plus mitomycin C in advanced non-small-cell lung cancer

In this phase III randomized study, 124 evaluable patients with unresectable non-small-cell lung cancer (NSCLC) were randomized to vindesine v cisplatin (120 mg/m2) plus vindesine v cisplatin (60 mg/m2) plus vindesine plus mitomycin C. The objective response rate for cisplatin and vindesine was 27% v 20% for cisplatin, vindesine, and mitomycin C, and 14% for vindesine alone (P = .25 for cisplatin and vindesine v vindesine). The percentage of patients having stable disease (no progression for a minimum of 3 months) was 20% (cisplatin and vindesine), 27% (cisplatin, vindesine, and mitomycin C), and 26% (vindesine alone), respectively. The median survival time for vindesine was 18 weeks, compared with 26 weeks for cisplatin and vindesine and 17 weeks for cisplatin, vindesine, and mitomycin C. Overall survival was not statistically different for cisplatin plus vindesine v vindesine (P = .65). There was no evidence for improved duration of remission or survival of responders with the cisplatin (120 mg/m2) and vindesine arm. This study failed to demonstrate sufficient therapeutic benefit for cisplatin and vindesine (+/- mitomycin C) compared with single-agent vindesine to justify the increased cost and toxicity of these combination regimens.

Response of turkey poults to aerosolized spores of Aspergillus fumigatus and aflatoxigenic and nonaflatoxigenic strains of Aspergillus flavus

Groups of 3-week-old turkey poults were exposed to aerosols containing spores of either Aspergillus fumigatus or aflatoxigenic or nonaflatoxigenic strains of Aspergillus flavus. Approximately 5 X 10(5) spores of A. fumigatus/gm of lung tissue killed about 50% of the turkey poults with A. funigatus, whereas doses approximating this level with either of the A. flavus strains did not cause any mortalities for up to 8 weeks postexposure. Fungi were isolated from lung tissue of 60% of the birds surviving for 8 weeks after exposure to spores of A fumigatus, but A. flavus was isolated from lung tissue from only 20% of the birds 8 weeks after exposure to either A. flavus strain. Almost all birds exposed to A. fumigatus developed precipitating antibodies, whereas none of the birds exposed to A. flavus developed precipitating antibodies. The lesions in the lung tissue from birds exposed to A. fumigatus were larger, were more numerous, and involved a greater percentage of tissue than was observed in lung tissue from birds exposed to A. flavus. There were no apparent differences in pathogenicity between the A. flavus strains. Aflatoxin was not detected in tissues from birds exposed to the aflatoxigenic strain of A. flavus, and there were no signs of aflatoxigenic when sections of liver from these birds were examined histopathologically.