Male Sexual Dysfunction and Infertility in Spinal Cord Injury Patients: State-of-the-Art and Future Perspectives.

Spinal cord injury (SCI) is a relevant medical and social problem. According to the World Health Organization, the commonly estimated worldwide annual incidence of SCI is 40 to 80 cases per million population. After the SCI experience, most men present with sexual dysfunction (erectile dysfunction (ED) and ejaculatory dysfunction), fertility problems (such as impaired spermatogenesis, abnormalities in sperm viability, motility, and morphology), and systemic disorders such as genitourinary infection and endocrine imbalances. The best options available for managing the ejaculatory disorders in patients suffering from SCI are penile vibratory stimulation (PVS) and electroejaculation (EEJ). Furthermore, the treatment of ED in SCI patients consists of medical therapies including phosphodiesterase 5 inhibitors (PDE5i), intracavernosal injections (ICI), vacuum erection devices (VEDs), and surgical as penile prosthesis (PP). This review provides a snapshot of the current evidence for the mechanisms of sexual dysfunction and infertility in SCI patients, discusses the best management strategies for these conditions, and offers our perspective on the direction of future research.

Proton irradiation: a key to the challenge of N-glycosidic bond formation in a prebiotic context.

The formation of nucleosides in abiotic conditions is a major hurdle in origin-of-life studies. We have determined the pathway of a general reaction leading to the one-pot synthesis of ribo- and 2'-deoxy-ribonucleosides from sugars and purine nucleobases under proton irradiation in the presence of a chondrite meteorite. These conditions simulate the presumptive conditions in space or on an early Earth fluxed by slow protons from the solar wind, potentially mimicking a plausible prebiotic scenario. The reaction (i) requires neither pre-activated precursors nor intermediate purification/concentration steps, (ii) is based on a defined radical mechanism, and (iii) is characterized by stereoselectivity, regioselectivity and (poly)glycosylation. The yield is enhanced by formamide and meteorite relative to the control reaction.

New evolutionary insights into the non-enzymatic origin of RNA oligomers.

We outline novel findings on the non-enzymatic polymerization of nucleotides under plausible prebiotic conditions and on the spontaneous onset of informational complexity in the founding molecule, RNA. We argue that the unique ability of 3', 5' cyclic guanosine monophosphate to form stacked architectures and polymerize in a self-sustained manner suggests that this molecule may serve as the 'seed of life' from which all self-replicating oligonucleotides can be derived via a logically complete sequence of simple events. WIREs RNA 2017, 8:e1400. doi: 10.1002/wrna.1400 For further resources related to this article, please visit the WIREs website.

From formamide to RNA, the path is tenuous but continuous.

Reactions of formamide (NH2COH) in the presence of catalysts of both terrestrial and meteoritic origin yield, in plausible and variegated conditions, a large panel of precursors of (pre)genetic and (pre)metabolic interest. Formamide chemistry potentially satisfies all of the steps from the very initial precursors to RNA. Water chemistry enters the scene in RNA non-enzymatic synthesis and recombination.