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Cytomegalovirus (CMV) pneumonia is a life-threatening infection in patients with haematological malignancies (HMs) or in haematopoietic stem cell transplant (HSCT) recipients. To assess the incidence and risk factors for developing fatal CMV pneumonia in these patients, a case–control study based on 999 autopsies was performed at The University of Texas M. D. Anderson Cancer Center, Houston, Texas (January 1990 to December 2004). Twenty-five cases (patients who died with CMV pneumonia) were matched with 34 controls (patients who died without CMV pneumonia) by type of HM or HSCT, year of autopsy, age and gender. The incidence of CMV pneumonia declined between January 1990 to June /1997 and July 1997 to December 2004 (CMV pneumonia rates were 22/620 and 3/379 autopsies, respectively; p 0.006). Logistic regression analysis identified complete remission and sustained lymphopenia as independent predictors of CMV pneumonia (all p <0.05). The incidence of fatal CMV pneumonia has decreased over the last 15 years, which might reflect earlier diagnosis or the use of pre-emptive therapy or more effective preventive strategies. Complete remission of an HM does not preclude the development of CMV pneumonia among patients with prolonged lymphopenia. [ABSTRACT FROM AUTHOR]

A Mars sample return (MSR) mission must deal with two new categories of planetary protection requirements: (1) assuring a very low probability of inadvertent release of the sample in order to provide extra protection against the extremely unlikely possibility of biological hazards in the returned material and (2) keeping the samples free of round-trip Earth organisms to facilitate confirmation of safety after return to Earth. This paper describes the planetary-protection-related technical challenges awaiting an MSR mission as well as the range of capabilities being developed to meet these challenges. Containment assurance requires breaking the chain of contact with Mars: the exterior of the sample container must not be contaminated with Mars material. The sample container and its seals must be designed to survive Earth impacts corresponding to the candidate mission profiles, and the Earth entry vehicle must be designed to withstand the thermal and structural rigors of Earth atmosphere entry (all with an unprecedented degree of confidence). Sample contamination must be avoided by sterilizing the entire spacecraft, a challenge with modern avionics, or by sterilizing the sample collection and containment gear and then isolating it from other parts of the spacecraft. [Copyright &y& Elsevier]

For Mars in situ landed missions, it has become increasingly apparent that significant value may be provided by a shared system that we call a Sample Preparation and Distribution (SPAD) System. A study was conducted to identify the issues and feasibility of such a system for these missions that would provide common functions for: receiving a variety of sample types from multiple sample acquisition systems; conducting preliminary characterization of these samples with non-destructive science instruments and making decisions about what should happen to the samples; performing a variety of sample preparation functions; and, finally, directing the prepared samples to additional science instruments for further analysis. Scientific constraints on the functionality of the system were identified, such as triage, contamination management, and various sample preparation steps, e.g., comminution, splitting, rock surfacing, and sieving. Some simplifying strategies were recommended and an overall science flow was developed. Engineering functional requirements were also investigated and example architectures developed. Preliminary conclusions are that shared SPAD facility systems could indeed add value to future Mars in situ landed missions if they are designed to respond to the particular requirements and constraints of those missions, that such a system appears feasible for consideration, and that certain standards should be developed for key SPAD interfaces. [Copyright &y& Elsevier]