SARS-CoV-2 N Gene G29195T Point Mutation May Affect Diagnostic Reverse Transcription-PCR Detection

Accurate diagnostic detection of SARS-CoV-2 currently depends on the large-scale deployment of RT-PCR assays. SARS-CoV-2 RT-PCR assays target predetermined regions in the viral genomes by complementary binding of primers and probes to nucleic acid sequences in the clinical samples.

Multiplexed, High-Sensitivity Measurements of Antibody Affinity Using Interferometric Reflectance Imaging Sensor

Anthrax lethal factor (LF) is one of the enzymatic components of the anthrax toxin responsible for the pathogenic responses of the anthrax disease. The ability to screen multiplexed ligands against LF and subsequently estimate the effective kinetic rates (kon and koff) and complementary binding behavior provides critical information useful in diagnostic and therapeutic development for anthrax. Tools such as biolayer interferometry (BLI) and surface plasmon resonance imaging (SPRi) have been developed for this purpose; however, these tools suffer from limitations such as signal jumps when the solution in the chamber is switched or low sensitivity. Here, we present multiplexed antibody affinity measurements obtained by the interferometric reflectance imaging sensor (IRIS), a highly sensitive, label-free optical biosensor, whose stability, simplicity, and imaging modality overcomes many of the limitations of other multiplexed methods. We compare the multiplexed binding results obtained with the IRIS system using two ligands targeting the anthrax lethal factor (LF) against previously published results obtained with more traditional surface plasmon resonance (SPR), which showed consistent results, as well as kinetic information previously unattainable with SPR. Additional exemplary data demonstrating multiplexed binding and the corresponding complementary binding to sequentially injected ligands provides an additional layer of information immediately useful to the researcher.

The promising use of nano-molecular imprinted templates for improved SARS-CoV-2 detection, drug delivery and research

Molecular imprinting (MI) is a technique that creates a template of a molecule for improving complementary binding sites in terms of size and shape to a peptide, protein, bacteria, mammalian cell, or virus on soft materials (such as polymers, hydrogels, or self-assembled materials). MI has been widely investigated for over 90 years in various industries but is now focused on improved tissue engineering, regenerative medicine, drug delivery, sensors, diagnostics, therapeutics and other medical applications. Molecular targets that have been studied so far in MI include those for the major antigenic determinants of microorganisms (like bacteria or viruses) leading to innovations in disease diagnosis via solid-phase extraction separation and biomimetic sensors. As such, although not widely investigated yet, MI demonstrates much promise for improving the detection of and treatment for the current Coronavirus Disease of 2019 (COVID-2019) pandemic as well as future pandemics. In this manner, this review will introduce the numerous applications of MI polymers, particularly using proteins and peptides, and how these MI polymers can be used as improved diagnostic and therapeutic tools for COVID-19. Graphic Abstract

Administration of simvastatin halts progression of cirrhosis via up-regulating expression of miR-34a and interleukin-10 in rats

IntroductionSimvastatin (SIM) treatment has been found to be able to reduce the expression of miR-34a, and we found that interleukin-10 (IL-10) is a potential target gene of miR-34a by searching the online microRNA (miRNA) database. Furthermore, it has been shown that IL10 up-regulation could halt the progression of cirrhosis. The objective of this study was to explore the underlying mechanism of Simvastatin/miR-34a/IL-10 involved in HBV associated cirrhosis.Material and methodsReal-time PCR, western-blot analysis, immunohistochemistry, computational analysis, luciferase assay was carried out to explore the underlying mechanism of miR-34a involved in HBV associated cirrhosis.ResultsSIM treatment dose-dependently decreased the levels of miR-34a while increasing the levels of IL-10 mRNA and protein. Levels of IL-10 mRNA and protein were remarkably decreased, while miR-34a mRNA level and active caspase-3 protein level was apparently increased in Cirrhosis group compared with sham group. Accordingly, SIM treatment obstructed the dysregulated miR-34a expression and IL-10 expression in cirrhosis animals. By performing computational analysis, we identified that a complementary binding site of miR-34a was located in IL-10 3’ untranslated region (3’UTR), and miR-34a reduced luciferase activity of wild-type IL-10 3’UTR.ConclusionsOur data also suggested that SIM may become a new therapeutic strategy for HBV-associated cirrhosis via targeting the miR-34a/IL-10 axis.

Erratum

Glioma is the most common and lethal malignant intracranial tumor. Long noncoding RNAs (lncRNAs) have been identified as pivotal regulators in the tumorigenesis of glioma. However, the role of lncRNA urothelial carcinoma-associated 1 (UCA1) in glioma genesis is still unknown. The purpose of this study was to investigate the underlying function of UCA1 on glioma genesis. The results demonstrated that UCA1 was upregulated in glioma tissue and indicated a poor prognosis. UCA1 knockdown induced by si-UCA1 significantly suppressed the proliferative, migrative, and invasive activities of glioma cell lines (U87 and U251). Bioinformatics analysis and luciferase reporter assay verified the complementary binding within UCA1 and miR-122 at the 3-UTR. Functional experiments revealed that UCA1 acted as an miR-122 sponge to modulate glioma cell proliferation, migration, and invasion via downregulation of miR-122. Overall, the present study demonstrated that lncRNA UCA1 acts as an endogenous sponge of miR-122 to promote glioma cell proliferation, migration, and invasion, which provides a novel insight and therapeutic target in the tumorigenesis of glioma.

MiR-599 Protects Cardiomyocytes against Oxidative Stress-Induced Pyroptosis

Oxidative stress is a crucial factor and key promoter of a variety of cardiovascular diseases associated with cardiomyocyte injury. Emerging literatures suggest that pyroptosis plays a key role in cardiac damages. However, whether pyroptosis contributes to cardiomyocyte injury under oxidative stress and the underlying molecular mechanisms are totally unclear. This study was designed to investigate the potential role of pyroptosis in H2O2-induced cardiomyocyte injury and to elucidate the potential mechanisms. Primary cardiomyocytes from neonatal Wistar rats were utilized. These myocytes were treated with different concentrations of H2O2 (25, 50, and 100 μM) for 24 h to induce oxidative injury. Our results indicated that mRNA and protein levels of ASC were remarkably upregulated and caspase-1 was activated. Moreover, the expressions of inflammatory factors IL-1β and IL-18 were also increased. Luciferase assay showed that miR-599 inhibited ASC expression through complementary binding with its 3 ′ UTR. MiR-599 expression was substantially reduced in H2O2-treated cardiomyocytes. Upregulation of miR-599 inhibited cardiomyocyte pyroptosis under oxidative stress, and opposite results were found by decreasing the expression of miR-599. Consistently, miR-599 overexpression ameliorated cardiomyocyte injury caused by H2O2. Therefore, miR-599 could be a promising therapeutic approach for the management of cardiac injury under oxidative condition.

MiRNA-128-3p Restrains Malignant Melanoma Cell Malignancy by Targeting NTRK3

The functions of non-coding RNA, including microRNA (miRNA), have attracted considerable attention in the field of oncology, In this report, we examined the roles and molecular mechanisms of miR-128-3p, as related to the biological behaviors of malignant melanoma (MM). We found that miR-128-3p was expressed in low levels in these MM cells and may serve as a tumor suppressor by inhibiting proliferation, migration, and invasion, as well as inducing apoptosis in these MM cells. Moreover, neurotrophin receptor 3 (NTRK3), which serves as an oncogene that can enhance malignant behaviors of MM cells, was up-regulated in MM cells. Our current survey disclosed a complementary binding between miR-128-3p and the NTRK3 3′ untranslated regions (3′-UTR), while luciferase activities of NTRK3 3′-UTR were restrained by miR-128-3p in 293T cells. The effects of pre-miR-128-3p and sh-NTRK3 as well as anti-miR-128-3p and NTRK3(+) appeared to function synergistically in producing malignant progression. Moreover, there were possible to have counteracted effects for pre-miR-128-3p and NTRK3(+) in malignant progression. These findings established that miR-128-3p can function as a tumor suppressor by inhibiting carcinogenesis of the oncogene, NTRK3. Collectively, miR-128-3p and NTRK3 genes participate in modulating the malignant behavior of MM, and may represent new therapeutic targets for MM.

Supramolecular polymers with reversed viscosity/temperature profile for application in motor oils

We report novel supramolecular polymers, which possess a reversed viscosity/temperature profile. To this end, we developed a series of ditopic monomers featuring two self-complementary binding sites, either the guanidiniocarbonyl pyrrole carboxylic acid (GCP) or the aminopyridine carbonyl pyrrole carboxylic acid (ACP). At low temperatures, small cyclic structures are formed. However, at elevated temperatures, a ring–chain transformation leads to the formation of a supramolecular polymer. We demonstrate that this effect is dependent on the concentration of the solution and on the polarity of the solvent. This effect can counteract the loss of viscosity of the solvent at elevated temperatures, thus opening an application of our systems as viscosity index improvers (VIIs) in working fluids. This was tested for different motor oils and led to the identification of one compound as a promising VII.

Moleculary imprinted micro- and nanoparticles for cancer associated glycan motifs

Sialic acids are an important family of monosaccharides that are typically found as terminal moieties of glycans. Aberrant sialylation has been proven to correlate with various diseases including cancer. Glycosylation analysis is complex due to high diversityof the glycan isomers and their low abundance. Antibodies and lectins are commonly used in glycan purification and enrichment. However, high cost, poor availability, and limitation in storage/testing conditions hinders their application on a broader scale. This thesis is focused on the development of alternative glycan specific receptors with their potential applications in glycomics and cell imaging. The underlying technique for producing the synthetic receptors is molecular imprinting. Highly complementary binding sites are formed by fixing pre-ordered template/functional monomer complexes into a highly crosslinked polymer matrix. Fundamental investigation of this intermolecular imprinting approach in the imprinting of glycosylated targets is reported here. The core of this study focuses on the elucidation of relative contribution of orthogonally interacting functional monomers, their structural tuning and the importance of monomer, solvent and counterion choice on the imprinting. Molecularly imprinted polymers (MIPs) are developed as particles of different sizes for glycan/glycopeptide enrichment applications or combined with fluorescent reportergroups for use as glycan imaging nanolabels. Special attention is given to the improvement of sialic acid MIP selectivities toward particular structures associated with cancer biomarkers. Development of MIPs against such complex targets includes design of linkage selective MIPs with comprehensive studies of the affinities and selectivities of the final glycan specific materials.

The Modulation of miR-195-TGF-β/Smad3 Pathway on Proliferation, Apoptosis and Invasion of Glioma Cells

Glioma is one of the most common malignant tumors of the central nervous system with the high incidence. The abnormal expression of Smad3 is related to the occurrence, progression, metastasis, and drug resistance of various kinds of tumors. It was reported that the decreased expression of miR-195 was related to the onset of glioma. This study aims to explore whether miR-195 plays an important role in regulating Smad3 and influencing the cell biology of glioma. Bioinformatics analysis was performed to determine the target complementary binding site between miR-195 and Smad3. The expressions of miR-195 and Smad3 mRNA were measured in tumor tissue of patients with glioma.In vitro culture, SHG-44 cells were divided into 2 groups: miR-NC group, miR-195 mimic group. The expression of miR-195 was detected by qRT-PCR, and expression of Smad3 was measured by western blot. Apoptosis was detected by flow detection. Cell proliferation and cell invasion ability was detected by Ed U staining and Transwell experiments respectively. Our result showed that, compared with that of the carcinoma tissue, the expressions of miR-195 and Smad3 in glioma tissue were decreased significantly. Compared with normal glial cells HEB, the expression of miR-195 was decreased significantly, whereas the expression of Smad3 was increased significantly. The transfection of miR-195 mimic significantly reduced the expression Smad3 and p-Smad3, which significantly reduced the ability of cell proliferation, and increased apoptosis. In conclusion, miR195 can target regulate proliferation, apoptosis and invasion of glioma cells through TGF-β /Smad3 pathway.