SOI-nanowire biosensor for detection of D-NFATc1 protein

The nanowire (NW) detection is one of the fast-acting and high-sensitive methods, which can recognize potentially relevant protein molecules. A NW-biosensor based on the silicon-on-insulator (SOI)-structures has been used for biospecific label-free real time detection of the NFATc1 (D-NFATc1) oncomarker. For this purpose, SOI-nanowires (NWs) were modified with aptamers against NFATc1 used as molecular probes. It was shown that using this biosensor it is possible to reach sensitivity of 10^?15 M. This sensitivity was comparable to that of the NW-biosensor with immobilized antibodies used as macromolecular probes. The results demonstrate that approaches used in this study are promising for development of sensor elements for high-sensitive diagnostics of diseases.     

SARS-CoV-2 Nsp3 unique domain SUD interacts with guanine quadruplexes and G4-ligands inhibit this interaction

The multidomain non-structural protein 3 (Nsp3) is the largest protein encoded by coronavirus (CoV) genomes and several regions of this protein are essential for viral replication. Of note, SARS-CoV Nsp3 contains a SARS-Unique Domain (SUD), which can bind Guanine-rich non-canonical nucleic acid structures called G-quadruplexes (G4) and is essential for SARS-CoV replication. We show herein that the SARS-CoV-2 Nsp3 protein also contains a SUD domain that interacts with G4s. Indeed, interactions between SUD proteins and both DNA and RNA G4s were evidenced by G4 pull-down, Surface Plasmon Resonance and Homogenous Time Resolved Fluorescence. These interactions can be disrupted by mutations that prevent oligonucleotides from folding into G4 structures and, interestingly, by molecules known as specific ligands of these G4s. Structural models for these interactions are proposed and reveal significant differences with the crystallographic and modeled 3D structures of the SARS-CoV SUD-NM/G4 interaction. Altogether, our results pave the way for further studies on the role of SUD/G4 interactions during SARS-CoV-2 replication and the use of inhibitors of these interactions as potential antiviral compounds.     

HABITAT USE AND PREFERENCES OF INDO-PACIFIC HUMPBACK DOLPHINS SOUSA CHINENSIS IN ALGOA BAY, SOUTH AFRICA

This paper examines environmental and behavioral determinants of the habitat use and preferences of Indo-Pacific humpback dolphins inhabiting the Algoa Bay region on the south Eastern Cape coast of South Africa. In order to quantify the habitat use and preference, two indices were used, the Coefficient of Area Use (AU) and the Activity Index (AI). The dolphins inhabit a narrow strip of shallow, inshore waters of Algoa Bay and remain mostly within 400 m of the shore, in water less than 15 m deep, with no apparent preference for clear or turbid water. Water depth is probably the main factor limiting their inshore distribution, and the 25-m isobath seems to represent the critical depth. Within this confined, inshore distribution, dolphin activities concentrate in the vicinity of rocky reefs-their primary feeding grounds. Dolphin dependence on these shallow-water habitats is evident throughout the year and, consequently, the inshore shallow reefs are identified as the "key habitat" which is of primary importance for humpback dolphins in Eastern Cape waters. The dolphins' dependence on this restricted type of habitat within an already restricted inshore distribution makes them particularly vulnerable to alteration or loss of this habitat.     

Structural studies and physiological activity of lemnan, a pectin fromLemna minor L

A pectic polysaccharide, lemnan, was isolated from freshly collected duckweedLemna minor L. Its sugar chain was shown to be mainly composed of the residues ofD-galacturonic acid (64%), galactose, arabinose, xylose, andD-apiose, a branched chain sugar. The high content ofD-apiose (25%) indicated that lemnan is an apiogalacturonan type pectin similar to zosteran, a pectic polysaccharide from a sea phanerogam of the Zosteraceae family. The results of partial acidic hydrolysis, pectinase digestion, and NMR studies of lemnan demonstrated that its macromolecule contains regions of the linear α-1,4-D-galacturonan and branched apiogalacturonan. The side chains of apiogalacturonan were found to be formed of single and 1,5-linked residues ofD-apiofuranose attached to 2- and 3-positions of theD-galacturonic acid residues of the apiogalacturonan backbone. Lemnan was shown to exhibit an immunomodulatory effect activating the system of phagocytosis.     

Alterations in Nitric Oxide Activity and Sensitivity in Early Streptozotocin-Induced Diabetes Depend on Arteriolar Size

Changes in NO activity may play an important role in the early increase in microvascular flow that has been implicated in the pathogenesis of diabetic microangiopathy. We assessed, in the in situ spinotrapezius muscle preparation of 6 weeks'' streptozotocin-diabetic rats (n = 6) and of agematched controls (n = 8), basal inside diameters of A2–A4 arterioles and the reactivity to topically applied acetylcholine and nitroprusside, before and after N^G-nitro-L-arginine. In diabetic rats, cholinergic vasodilatation in A2–A4 arterioles was intact. Basal diameter in A3 and A4 arterioles was significantly higher in streptozotocin-diabetic rats. The increased basal diameter in A3 arterioles was partially due to an increased contribution of NO to basal diameter. The response to nitroprusside was impaired in streptozotocin-diabetic rats in A2, but not in A3 and A4 arterioles. Thus, this study shows that NO activity and sensitivity are altered after 6 weeks of streptozotocin-induced diabetes. These streptozotocin-induced changes are anatomically specific and, for arterioles, depend on their position within the vascular tree.     

Morariopsis dumonti n.sp. (Crustacea: Copepoda: Harpacticoida) – a new species from an unsaturated karstic zone in Slovenia

The genus Morariopsishas a disjunct distribution. It has been found in south-eastern Europe and in the Baikal region in Russia. In Europe two species are known, both from the Dinaric region. They have been found in three caves only, but always in puddles filled with percolating water. This indicates that they inhabit an unsaturated karstic environment. A third species, Morariopsis dumontin.sp has now been found, in the same type of habitat, on several dates, in a small cave in central Slovenia. Males were recorded for the first time in this genus.The new species is related to Morariospsis kieferiPetkovski, 1959 from Dalmatia. The main differences are in the ornamentation of the furca and of the abdominal segments. P5 and particularly endopodite of P4 in males suggest a close relation between Morariaand Morariopsis.