bioRxiv Science⌕ Search

Biology subjects

Zana, B.

Publications and source records attributed to Zana, B..

7 recordsLinked to original sources

The redesign of the molecular scaffold of viral ion channel blockers

The rise of new, rapidly mutating viruses presents increasing challenges for drug developers. Traditional methods, such as high-throughput screening and drug repurposing against mutagenic viral targets, have recently shown their limitations. Our current rational molecular engineering approach offers a sustainable solution by targeting viral ion channels, which generally have low mutation rates. First, extending the amantadine molecule led to the development of new compounds that better match the alternating hydrophobic and hydrophilic patterns of the inner walls of ion channels--a common feature across many viruses. Then, simplifying the structure yielded a cyclohexylamine-based minimalist scaffold that effectively blocks the ion channel and demonstrates improved antiviral activity compared to well-known agents such as amantadine and arterolane. SARS-CoV-2 variants served as test systems in laboratory experiments. The new molecular scaffolds presented here provide a strong foundation for designing potent, broad-spectrum viral ion channel blockers.

pharmacology and toxicology↗

Vividness of Visual Imagery Supported by Intrinsic Structural-Functional Brain Network Dynamics

Vividness of visual imagery is subject to individual variability, a phenomenon with largely unexplored neurobiological underpinnings. By analyzing data from 273 participants we explored the link between the structural-functional organization of brain connectomes and the reported intensity of visual imagery (measured with VVIQ-2). Employing graph theory analyses we investigated both the structural (DTI) and functional (rs-fMRI) connectomes within a network of regions often implicated in visual imagery. Our results indicate a relationship between increased local efficiency and clustering coefficients in the structural connectome in individuals who experience more vivid visual imagery. Increased local efficiency and clustering coefficients were mirrored in the functional connectome with increases in left inferior temporal regions, a region frequently identified as a critical hub in the visual imagery literature. Furthermore, individuals with more vivid imagery were found to have lower levels of global efficiency in their functional connectome. We propose that the clarity and intensity of visual imagery are optimized by a network organization characterized by heightened localized information transfer and interconnectedness. Conversely, an excessively globally integrated network might dilute the specific neural activity crucial for generating vivid visual images, leading to less locally concentrated resource allocation in key regions involved in visual imagery vividness.

neuroscience↗

Isolation and genome characterization of Lloviu virus from Italian Schreibers bent-winged bats

Lloviu cuevavirus (LLOV) was the first identified member of Filoviridae family outside the Ebola and Marburgvirus genera. A massive die-off of Schreibers bent-winged bats (Miniopterus schreibersii) in the Iberian Peninsula in 2002 led to its discovery. Studies with recombinant and wild-type LLOV isolates confirmed the susceptibility of human-derived cell lines and primary human macrophages to LLOV infection in vitro. Based on these data, LLOV is now considered as a potential zoonotic virus with unknown pathogenicity to humans and bats. We examined bat samples from Italy for the presence of LLOV in an area outside of the currently known distribution range of the virus. We detected one positive sample from 2020, sequenced the complete coding sequence of the viral genome and established an infectious isolate of the virus. In addition, we performed the first comprehensive evolutionary analysis of the virus, using the Spanish, Hungarian and the Italian sequences. The most important achievement of this article is the establishment of an additional infectious LLOV isolate from a bat sample using the SuBK12-08 cells, demonstrating that this cell line is highly susceptible to LLOV infection. These results further confirms the role of these bats as the host of this virus, possibly throughout their entire geographic range. This is an important result to further understand the role of bats as the natural hosts for zoonotic filoviruses.

microbiology↗

In-depth Temporal Transcriptome Profiling of Monkeypox and Host Cells using Nanopore Sequencing

The recent Monkeypox outbreak showed the importance of studying the basic biology of orthopoxviruses. However, the transcriptome of its causative agent has not been investigated before neither with short-, nor with long-read sequencing approaches. This Oxford Nanopore long-read RNA-Sequencing dataset fills this gap. Our direct cDNA and native RNA sequencing data enable the in-depth characterization of the transcriptomic architecture and dynamics of the gene expressions of monkeypox virus; and also the deeper understanding of the changes it causes in the host cells on a transcriptome level.

microbiology↗

A possible way to relate the effects of SARS-CoV-2 induced changes in transferrin to severe COVID-19 associated diseases

The potentially life-threatening Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is responsible for the coronavirus pandemic in 2019 (COVID-19). The transferrin as an essential component of iron-metabolism was suggested to be a link between iron transport associated diseases and COVID-19 infection. The effect of SARS-CoV-2 on human whole blood was studied by differential scanning calorimetry. The analysis and deconvolution of the thermal transition curves showed that the Tm of transferrin related second peak decreased by 5.16 {degrees}C (6.4%) in the presence of SARS-CoV-2 virus. The ratio of the under-curve area of the two main peaks was greatly affected while the total enthalpy of the heat denaturation was nearly unchanged in the presence of the virus. Based on the results it is possible to conclude that SARS-CoV-2 through binding to transferrin can influence its Fe3+ uptake by inducing thermodynamic changes. Transferrin may stay in iron-free apo-conformational state, which probably depends on the SARS-CoV-2 concentration. SARS-CoV-2 might induce disturbance in the erythropoiesis due to the free iron overload generated iron toxicity. As a late consequence iron toxicity related hepatocellular carcinoma can even develop. Our work can support the basic role of transferrin in COVID-19 related severe diseases.

biophysics↗

Reservoir host studies of Lloviu virus: first isolation, sequencing and serology in Schreiber's bats in Europe

IntroductoryFiloviruses are prime examples of emerging human pathogens that are transmitted to humans by zoonotic spillover events. Since their initial discovery, filovirus outbreaks have occured with increasing frequency and intensity. There is an urgent need to better understand their enzootic ecology and pathogenic potential, given recent zoonotic virus spillover events including the 2013-2016 West African Ebola virus (EBOV) epidemic. Several novel filoviruses have been discovered with a markedly wider geographic distribution than previously described. One of these novel filoviruses, Lloviu virus (LLOV), was first identified in 2002 in Schreibers bats (Miniopterus schreibersii) in Spain, Portugal, and southern France. Subsequently, in 2016, LLOV was detected during the passive monitoring of bats in Hungary. Here we report the first isolation of infectious Lloviu virus; from the blood of an asymptomatic Schreibers bat, subsequently cultivated in the Miniopterus sp. kidney cell line SuBK12-08. We also show that LLOV is able to infect monkey and human cells, suggesting that LLOV might have spillover potential. We performed a multi-year surveillance of LLOV and detected LLOV RNA in both deceased and asymptomatic live animals as well as in coupled ectoparasites from the families Nycteribiidae and Ixodidae. We present data on the natural infection and seropositivity of Schreibers bats and provide novel LLOV genomic sequence information from a bat host and an arthropod parasite. Our data support the role of bats, specifically Miniopterus schreibersii as natural reservoirs for the LLOV filovirus in Europe. We also suggest that bat-associated parasites might play a role in the natural ecology of filoviruses in temperate climate regions compared to filoviruses in the tropics. These results raise the possibility of cross-species transmission events via bat-human interactions.

microbiology↗

Small interfering RNAs are highly effective inhibitors regarding Crimean-Congo hemorrhagic fever virus replication in vitro

Crimean-Congo hemorrhagic fever virus (CCHFV) is one of the prioritized diseases of World Health Organization, considering its potential to create a public health emergency and more importantly, the absence of efficacious drugs and/or vaccines regarding treatment. The highly lethal nature characteristic to CCHFV restricts research to BSL-4 laboratories, which complicates effective research and developmental strategies. In consideration of antiviral therapies, RNA interference can be used to suppress viral replication by targeting viral genes. RNA interference uses small interfering RNAs (siRNAs) to silence genes. The aim of our study was to design siRNAs that inhibit CCHFV replication and can serve as a basis for further antiviral therapies. A549 cells were infected with CCHFV after transfection with the siRNAs. Following 72 hours, nucleic acid from the supernatant was extracted for Droplet Digital PCR analysis. Among the investigated siRNAs we identified four effective candidates against all three segments of CCHF genome: one for the S and M segments, whilst two for the L segment. Consequently, blocking any segment of CCHFV leads to changes in the virus copy number that indicates an antiviral effect of the siRNAs in vitro. The most active siRNAs were demonstrated a specific inhibitory effect against CCHFV in a dose-dependent manner. In summary, we demonstrated the ability of specific siRNAs to inhibit CCHFV replication in vitro. This promising result can be used in future anti-CCHFV therapy developments.

microbiology↗