A Novel Proteomics-Based Strategy for the Investigation of Peptide Sequences in Extraterrestrial Samples.

Method development is one of the objectives of the astrophysical community for characterizing the organic matter in objects of the solar system. In this context, we report on the development of an enzyme-catalyzed stereoselective hydrolysis, inspired by the proteomics discipline, which has enabled the indirect detection of peptide sequences in extraterrestrial samples. A proof of concept has been performed on a Murchison extract. We show that our approach can successfully highlight l- and d-amino acids involved in peptide bonds. While we show that some d-amino acids must have been involved in peptide bonds, we cannot at this stage conclude on the indigenous or exogenous nature of these biopolymers. However, our strategy constitutes the first step toward direct UPLC-MS evidence of peptide sequences in extraterrestrial samples. It should thus contribute to deepening knowledge on the molecules available in the solar system, hence providing new clues about their chemical history, especially on Earth.

Data-Driven Astrochemistry: One Step Further within the Origin of Life Puzzle.

Astrochemistry, meteoritics and chemical analytics represent a manifold scientific field, including various disciplines. In this review, clarifications on astrochemistry, comet chemistry, laboratory astrophysics and meteoritic research with respect to organic and metalorganic chemistry will be given. The seemingly large number of observed astrochemical molecules necessarily requires explanations on molecular complexity and chemical evolution, which will be discussed. Special emphasis should be placed on data-driven analytical methods including ultrahigh-resolving instruments and their interplay with quantum chemical computations. These methods enable remarkable insights into the complex chemical spaces that exist in meteorites and maximize the level of information on the huge astrochemical molecular diversity. In addition, they allow one to study even yet undescribed chemistry as the one involving organomagnesium compounds in meteorites. Both targeted and non-targeted analytical strategies will be explained and may touch upon epistemological problems. In addition, implications of (metal)organic matter toward prebiotic chemistry leading to the emergence of life will be discussed. The precise description of astrochemical organic and metalorganic matter as seeds for life and their interactions within various astrophysical environments may appear essential to further study questions regarding the emergence of life on a most fundamental level that is within the molecular world and its self-organization properties.

Uterine transplantation: what else needs to be done before it can become a reality?

Uterine transplantation may be a possible treatment option in the future for absolute uterine infertility. We describe three important areas of research that we feel are important in order to move closer to a successful and, crucially, safe transplant in the human setting. With closer collaboration among the various international teams working on this project, the first human uterine transplant should be possible in the next few years.

Second trimester selective termination of a twin with ruptured membranes: elimination of fluid leakage and preservation of pregnancy.

Second trimester selective termination has been used for 15 years to prevent the birth of children with fetal abnormalities. We have managed a twin pregnancy in which one twin had spontaneous rupture of membranes at 15 weeks, with continued fluid leakage and oligohydramnios. There was a high risk for infection, and selective termination was performed at 18 weeks of gestation, followed by the term delivery of the remaining twin. Selective termination may preserve the viability of the second twin otherwise considered at high risk for fetal loss.