Probe-Free Identification of RNA Virus Variants with Point Mutations by Surface-Enhanced Raman Spectroscopy.

As observed in the COVID-19 pandemic, RNA viruses continue to rapidly evolve through mutations. In the absence of effective therapeutics, early detection of new severely pathogenic viruses and quarantine of infected people are critical for reducing the spread of the viral infections. However, conventional detection methods require a substantial amount of time to develop probes specific to new viruses, thereby impeding immediate response to the emergence of viral pathogens.

TLR3 forms a highly organized cluster when bound to a poly(I:C) RNA ligand.

Toll-like Receptor 3 (TLR3) initiates a potent anti-viral immune response by binding to double-stranded RNA ligands. Previous crystallographic studies showed that TLR3 forms a homodimer when bound to a 46-base pair RNA ligand. However, this short RNA fails to initiate a robust immune response.

Engineering Genetic Systems for Treating Mitochondrial Diseases.

Mitochondria are intracellular energy generators involved in various cellular processes. Therefore, mitochondrial dysfunction often leads to multiple serious diseases, including neurodegenerative and cardiovascular diseases. A better understanding of the underlying mitochondrial dysfunctions of the molecular mechanism will provide important hints on how to mitigate the symptoms of mitochondrial diseases and eventually cure them.

Molecular-Level Interactions between Engineered Materials and Cells.

Various recent experimental observations indicate that growing cells on engineered materials can alter their physiology, function, and fate. This finding suggests that better molecular-level understanding of the interactions between cells and materials may guide the design and construction of sophisticated artificial substrates, potentially enabling control of cells for use in various biomedical applications. In this review, we introduce recent research results that shed light on molecular events and mechanisms involved in the interactions between cells and materials.

Attomolar detection of virus by liquid coplanar-gate graphene transistor on plastic.

The direct method of detecting a virus with extremely low concentration is recommended for the diagnosis of viral disease. In this study, coplanar-gate graphene field-effect transistors (GFETs) were built on flexible polyethylene terephthalate substrates for the attomolar detection of a virus. The GFETs exhibited a very low detection limit of 47.

Nanotopography-based engineering of retroviral DNA integration patterns.

Controlling the interactions between cells and viruses is critical for treating infected patients, preventing viral infections, and improving virus-based therapeutics. Chemical methods using small molecules and biological methods using proteins and nucleic acids are employed for achieving this control, albeit with limitations. We found, for the first time, that retroviral DNA integration patterns in the human genome, the result of complicated interactions between cells and viruses, can be engineered by adapting cells to the defined nanotopography of silica bead monolayers.

Recent Advances in Mitochondria-Targeted Gene Delivery.

Mitochondria are the energy-producing organelles of cells. Mitochondrial dysfunctions link to various syndromes and diseases including myoclonic epilepsy and ragged-red fiber disease (MERRF), Leigh syndrome (LS), and Leber hereditary optic neuropathy (LHON). Primary mitochondrial diseases often result from mutations of mitochondrial genomes and nuclear genes that encode the mitochondrial components.

Reliable RT-qPCR-based titration of retroviral and lentiviral vectors via quantification of residual vector plasmid DNA in samples.

Objectives: To develop a method for reliable quantification of viral vectors, which is necessary for determining the optimal dose of vector particles in clinical trials to obtain the desired effects without severe unwanted immune responses.

Results: A significant level of vector plasmid remained in retroviral and lentiviral vector samples, which led to overestimation of viral titers when using the conventional RT-qPCR-based genomic titration method. To address this problem, we developed a new method in which the residual plasmid was quantified by an additional RT-qPCR step, and standard molecules and primer sets were optimized.

Identification of Newly Emerging Influenza Viruses by Surface-Enhanced Raman Spectroscopy.

In this work, we demonstrate in situ virus identification based on surface-enhanced Raman scattering (SERS). We hypothesized that newly emerging influenza viruses possess surface proteins and lipids that can generate distinctive Raman signals. To test this hypothesis, SERS signals were measured from the surface of a noninfluenza virus, two different influenza viruses, and a genetically shuffled influenza virus.

[Performance evaluation of BD GeneOhm MRSA PCR assay for detection of nasal colonization of methicillin-resistant Staphylococcus aureus at endemic intensive care units].

Background: The BD GeneOhm MRSA PCR assay (Becton Dickinson, USA) is a qualitative real-time PCR test for rapid detection of nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA). We evaluated the performance of BD GeneOhm MRSA PCR assay versus MRSASelect (Bio-Rad, France) and broth enrichment cultures for detection of MRSA from nasal swabs.

Methods: From August 2008 to January 2009, 295 nasal swabs were taken from patients in intensive care units and transported to the laboratory with BD CultureSwab Liquid Stuart Single Swab (Becton Dickinson, USA).