Non-agglomerated silicon-organic nanoparticles and their nanocomplexes with oligonucleotides: synthesis and properties

YOLOv5-FPN: A Robust Framework for Multi-Sized Cell Counting in Fluorescence Images

Cell counting in fluorescence microscopy is an essential task in biomedical research for analyzing cellular dynamics and studying disease progression. Traditional methods for cell counting involve manual counting or threshold-based segmentation, which are time-consuming and prone to human error. Recently, deep learning-based object detection methods have shown promising results in automating cell counting tasks. However, the existing methods mainly focus on segmentation-based techniques that require a large amount of labeled data and extensive computational resources. In this paper, we propose a novel approach to detect and count multiple-size cells in a fluorescence image slide using You Only Look Once version 5 (YOLOv5) with a feature pyramid network (FPN). Our proposed method can efficiently detect multiple cells with different sizes in a single image, eliminating the need for pixel-level segmentation. We show that our method outperforms state-of-the-art segmentation-based approaches in terms of accuracy and computational efficiency. The experimental results on publicly available datasets demonstrate that our proposed approach achieves an average precision of 0.8 and a processing time of 43.9 ms per image. Our approach addresses the research gap in the literature by providing a more efficient and accurate method for cell counting in fluorescence microscopy that requires less computational resources and labeled data.

The Effect of Silicon Dioxide Nanoparticles Combined with Entomopathogenic Bacteria or Fungus on the Survival of Colorado Potato Beetle and Cabbage Beetles

Three types of modified silicon dioxide nanoparticles (SiO2, 10−20 nm) with additives of epoxy, silane and amino groups, used independently and in combination with the entomopathogenic bacteria Bacillus thuringiensis subsp. morrisoni and fungus Metarhizium robertsii were tested against Colorado potato beetle (Leptinotarsa decemlineata) and cabbage beetles (Phyllotreta spp.). All three nanoparticles were found to have an entomocidal effect on Colorado potato beetle larvae and crucifer flea beetles when ingested. Increased susceptibility of insects to B. thuringiensis or M. robertsii blastospores and their metabolites was shown after exposure to the modified silicon dioxide nanoparticles. The potential of modified silicon dioxide nanoparticles to enhance the efficiency of biopesticides based on the bacteria B. thuringiensis and fungi M. robertsii is considered in the paper.

Anti-Influenza Strategies Based on Nanoparticle Applications

Influenza virus has the potential for being one of the deadliest viruses, as we know from the pandemic's history. The influenza virus, with a constantly mutating genome, is becoming resistant to existing antiviral drugs and vaccines. For that reason, there is an urgent need for developing new therapeutics and therapies. Despite the fact that a new generation of universal vaccines or anti-influenza drugs are being developed, the perfect remedy has still not been found. In this review, various strategies for using nanoparticles (NPs) to defeat influenza virus infections are presented. Several categories of NP applications are highlighted: NPs as immuno-inducing vaccines, NPs used in gene silencing approaches, bare NPs influencing influenza virus life cycle and the use of NPs for drug delivery. This rapidly growing field of anti-influenza methods based on nanotechnology is very promising. Although profound research must be conducted to fully understand and control the potential side effects of the new generation of antivirals, the presented and discussed studies show that nanotechnology methods can effectively induce the immune responses or inhibit influenza virus activity both in vitro and in vivo. Moreover, with its variety of modification possibilities, nanotechnology has great potential for applications and may be helpful not only in anti-influenza but also in the general antiviral approaches.

Antisense Oligonucleotides Immobilized on Silicon-Organic Nanoparticles as a Tool for Prolonged Correction of Hypertensive States

We propose an original method for controlling BP by administration of Si~ODN nanocomposites containing antisense oligonucleotides fixed on silicon-organic nanoparticles. ODN in nanocomposites are targeted to mRNA of the genes encoding angiotensin-converting enzyme (ACE1) and type 1 angiotensin-II receptor (AT1A). The experiments were performed on hypertensive ISIAH rats, a genetic model of hypertension. Single inhalation or intraperitoneal administration of the nanocomposites targeted to ACE1 mRNA or ATA1 mRNA, respectively, led to a pronounced decrease (by ~30 mm Hg) in systolic BP in ISIAH rats over a week. The use of scrambled ODN in the nanocomposites had no effect. A decrease in the expression of ACE1 and AT1A genes under the effect of the corresponding antisense ODN was demonstrated, which attested to directed effect of the test preparations.

Methods of the Synthesis of Silicon-Containing Nanoparticles Intended for Nucleic Acid Delivery

A promising new approach to the treatment of viral infections and genetic diseases associated with damaged or foreign nucleic acids in the body is gene therapy, i.e., the use of antisense oligonucleotides, ribozymes, deoxyribozymes, siRNA, plasmid DNA, etc. (therapeutic nucleic acids). Selective recognition of target nucleic acids by these compounds based on highly specific complementary interaction can minimize negative side effects, which occur with currently used low molecular weight drugs. To apply a new generation of therapeutic agents in medical practice, it is necessary to solve the problem of their delivery into cells. Silicon-containing nanoparticles are considered as promising carriers for this purpose due to their biocompatibility, low toxicity, ability to biodegradation and excretion from the body, as well as the simplicity of the synthesis and modification. Silicon-containing nanoparticles are divided into two broad categories: solid (nonporous) and mesoporous silicon nanoparticles (MSN). This review gives a brief overview of the creation of mesoporous, multilayer, and other silicon-based nanoparticles. The publications concerning solid silicon-organic nanoparticles capable of binding and delivering nucleic acids into cells are discussed in more detail with emphasis on methods for their synthesis. The review covers publications over the past 15 years, which describe the classical Stöber method, the microemulsion method, modification of commercial silica nanoparticles, and other strategies.