The part played by the mucopolysaccharides in the form birefringence of the Collagen

We stressed in our wourk the necessity of knowing the details of the interaction between the acid mucopolysaccharides and the collagen. Employing the appropriate methods we carried out the measurements of birefringence of strictly limited parts of collagen bundles. The measurements were carried out before and after the collagen bundles were subjected to the action of testicular hyaluronidase.The statistic study of the data we arrived have revealed that the testicular hyaluronidase which removes the acid mucopolysaccharides causes a decrease of form birefringence.These results are discussed on the regard to former research with done by the author and the conclusions may be drawn that the acid mucopolysaccharides play a part in the form birefringence of collagen bundles, and therefore have a macromolecular orientation.The author is indebted to Prof. Lucien Lison who has done the statistical processing.     

The importance of naturally attenuated SARS-CoV-2in the fight against COVID-19

The current SARS-CoV-2 pandemic is wreaking havoc throughout the world and has rapidly become a global health emergency. A central question concerning COVID-19 is why some individuals become sick and others not. Many have pointed already at variation in risk factors between individuals. However, the variable outcome of SARS-CoV-2 infections may, at least in part, be due also to differences between the viral subspecies with which individuals are infected. A more pertinent question is how we are to overcome the current pandemic. A vaccine against SARS-CoV-2 would offer significant relief, although vaccine developers have warned that design, testing and production of vaccines may take a year if not longer. Vaccines are based on a handful of different designs (i), but the earliest vaccines were based on the live, attenuated virus. As has been the case for other viruses during earlier pandemics, SARS-CoV-2 will mutate and may naturally attenuate over time (ii). What makes the current pandemic unique is that, thanks to state-of-the-art nucleic acid sequencing technologies, we can follow in detail how SARS-CoV-2 evolves while it spreads. We argue that knowledge of naturally emerging attenuated SARS-CoV-2 variants across the globe should be of key interest in our fight against the pandemic.     

Conventional single-chamber pacemakers versus transcatheter pacing systems in a “real world” cohort of patients: A comparative prospective single-center study

PurposeDespite the developments in conventional transvenous pacemakers (VVI-PM), the procedure is still associated with significant complications. Although there are no prospective clinical trials that compared VVI-PM with transcatheter pacemaker systems (TPS).MethodsThis is a prospective, observational, single-center study that included all patients with an indication for a single-chamber pacemaker implant within a 4-year period. All clinical, ECG and echocardiographic characteristics at implant, electrical parameters, associated complications and mortality were analyzed. A Cox survival model and a Bayesian cohort analysis were performed for differences in complication rates between groups.ResultsThere were 443 patients included (198 TPS and 245 VVI-PM). The mean age was 81.5 years (TPS group, 79.2 ± 6.6 years; VVI-PM group, 83.5 ± 8.9 years). There was a male predominance in TPS group (123, 62.1% vs. 67, 27.3%; p < 0.001). The presence of systolic dysfunction and renal insufficiency were more frequent in VVI-PM group than in TPS patients. Mean follow-up was 22.3 ± 15.9 months. In a multivariable paired data the TPS group presented fewer complications than VVI-PM group (HR = 0.39 [0.15–0.98], p-value 0.013), but major complications were not different (6, 3% vs 14, 5.6% respectively, p = 0.1761). There was no difference in the mortality rate between the groups. The TPS group had less risk than VVI-PM group to have a complication, with a 96% of probability.ConclusionsTPS patients had a lower overall complication rate than VVI-PM patients including matched-pair samples using a Bayesian analysis. These results confirm the safety profile of TPS in clinical practice.     

Ancient saltern metagenomics: tracking changes in microbes and their viruses from the underground to the surface

Microbial communities in hypersaline underground waters derive from ancient organisms trapped within the evaporitic salt crystals and are part of the poorly known subterranean biosphere. Here, we characterized the viral and prokaryotic assemblages present in the hypersaline springs that dissolve Triassic-Keuper evaporite rocks and feed the Añana Salt Valley (Araba/Alava, Basque Country, Spain). Four underground water samples (around 23% total salinity) with different levels of exposure to the open air were analysed by means of microscopy and metagenomics. Cells and viruses in the spring water had lower concentrations than what are normally found in hypersaline environments and seemed to be mostly inactive. Upon exposure to the open air, there was an increase in activity of both cells and viruses as well as a selection of phylotypes. The underground water was inhabited by a rich community harbouring a diverse set of genes coding for retinal binding proteins. A total of 35 viral contigs from 15 to 104 kb, representing partial or total viral genomes, were assembled and their evolutionary changes through the spring system were followed by SNP analysis and metagenomic island tracking. Overall, both the viral and the prokaryotic assemblages changed quickly upon exposure to the open air conditions.     

Synthesis of Copper-64 and Technetium-99M Labeled Oligonucleotides with Macrocyclic Ligands

Abstract

An efficient procedure for the preparation of oligonucleotides carrying a mono-N-substituted azamacrocycle and its radiolabeled complex with Cu-64 and Tc-99m is reported. The new derivatives are of potential interest for Positron Emission Tomography and Single Photon Emission Tomography.     

A Monoclonal Antibody that Specifically Recognizes m'A Nucleoside

Abstract

A hybridoma against the nucleoside m⁶A has been obtained from mouse spleen. This hybridoma was named H65 and it secretes monoclonal antibodies anti-m⁶A. The competition assays showed that the monoclonal antibody was highly specific for m⁶A nucleoside.