Apparent Intracellular Helicobacter pylori Detected by Immunohistochemistry: The Missing Link in Eradication Failure.

BACKGROUND: Helicobacter pylori is primarily an extracellularly living bacterium. However, seemingly intracellular occurrence can often be detected by immunohistochemical stains. Considering antimicrobial resistance, we investigated the impact of the apparent intracellular H. pylori (aiHp) on treatment failure of first-line triple therapies. METHODS: Gastric biopsies of 814 patients infected with H. pylori naive to treatment were analyzed before and after eradication therapy by immunohistochemistry. Of these, 373 received treatment consisting of amoxicillin, clarithromycin, and proton pump inhibitor (AC/PPI). Availability of polymerase chain reaction-based clarithromycin susceptibility test results from pretreatment gastric biopsies was a precondition for matching 52 aiHp to 52 non-aiHp cases within the AC/PPI group. RESULTS: AiHp were detected mostly in low counts predominantly in corpus biopsies, rarely in antrum biopsies (95.2% vs 24.6%); they were found in 497 (61%) of all patients and in 192 of 373 patients (51.5%) in the AC/PPI group. The eradication rate in aiHp versus non-aiHp cases was 44.4% versus 72.9% in the entire sample and 45.3% versus 66.8% in the AC/PPI group. Among the 104 paired patients, respective values were 46.2% versus 78.8%; in clarithromycin-susceptible cases, 60.6% versus 91.9%. Both aiHp and resistance to clarithromycin proved to be highly significant (P ≤ .001) and independent predictors of eradication failure. Twelve of 13 aiHp cases with a clarithromycin-sensitive strain who failed eradication developed resistance to the antibiotic. CONCLUSIONS: AiHp found by immunohistochemical staining especially in corpus biopsies proved to be a risk factor for failure of first-line triple therapies; occurrence of aiHp should be considered with regard to therapy options.

AMADEE-18 and the Analog Mission Performance Metrics Analysis: A Benchmarking Tool for Mission Planning and Evaluation.

Analog research of human or combined human and robotic missions is an established tool to explore the workflows, instruments, risks, and challenges of future planetary surface missions in a representative terrestrial environment. Analog missions that emulate selected aspects of such expeditions have risen in number, expanded their range of disciplines covered, and seen a significant increase in their operational and programmatic impact on mission planning. We propose a method to compare analog missions across agencies, disciplines, and complexities/fidelities to improve scientific output and mission safety and maximize effectiveness and efficiency. This algorithm measures mission performance, provides a tool for an objective postmission evaluation, and catalyzes programmatic progress. It does not evaluate individual sites or instruments but focuses at mission level. By applying the algorithm to several missions, we compare the missions' performance for benchmarking purposes. Methodically, a combination of objective data sets and questionnaires is used to evaluate three areas: two sections of closed and quantitative questions and a third section dedicated to the level or representativeness of the test site. By using a weighted metric, the complexity and fidelity of a mission are compared with reference missions, which yield strengths and weaknesses in mission planning.

Laboratory Analysis of Returned Samples from the AMADEE-18 Mars Analog Mission.

Between February 1 and 28, 2018, the Austrian Space Forum, in cooperation with the Oman Astronomical Society and research teams from 25 nations, conducted the AMADEE-18 mission, a human-robotic Mars expedition simulation in the Dhofar region in the Sultanate of Oman. As a part of the AMADEE-18 simulated Mars human exploration mission, the Remote Science Support team performed analyses of the Dhofar area (Oman) in an effort to characterize the region as a potential Mars analog site. The main motivation of this research was to study and register selected samples collected by analog astronauts during the AMADEE-18 mission with laboratory analytical methods and techniques comparable with those that are likely to be used on Mars in the future. The 25 samples representing unconsolidated sediments obtained during the simulated mission were studied by using optical microscopy, Raman spectroscopy, X-ray diffraction, laser-induced breakdown spectroscopy, and laser-induced fluorescence spectroscopy. The principal results show the existence of minerals and alteration processes related to volcanism, hydrothermalism, and weathering. The analogy between the Dhofar region and the Eridana Basin region of Mars is clearly noticeable, particularly as an analog for secondary minerals formed in a hydrothermal seafloor volcanic-sedimentary environment. The synergy between the techniques used in the present work provides a solid basis for the geochemical analyses and organic detection in the context of future human-robotic Mars expeditions. AMADEE-18 has been a prime test bed for geoscientific workflows with astrobiological relevance and has provided valuable insights for future space missions.

The AMADEE-18 Mars Analog Expedition in the Dhofar Region of Oman.

From February 1 to 28, 2018, the Austrian Space Forum, in cooperation with the Oman Astronomical Society and research teams from 25 nations, conducted the AMADEE-18 mission, a human-robotic Mars expedition simulation in the Dhofar region in the Sultanate of Oman. A carefully selected field crew, supported by a Mission Support Center in Innsbruck, Austria, conducted 19 experiments relevant to astrobiology, engineering disciplines, geoscience, operations research, and human factors. This expedition was the 12th in a series of analog missions that emulate selected aspects of the science expected for a human Mars mission, including the characterization of the (paleo)geological environment, human factors studies, and the search for biomarkers. In particular, an Exploration Cascade was deployed as a suggested workflow for coordinating the timing and location of the respective instruments and experiments. In validation of this workflow, the decision-making interaction between the field and the Mission Support Center was studied. This article introduces the AMADEE-18 mission and provides the mission-specific context for the other contributions of this special issue.