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1.
Food Res Int ; 192: 114810, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39147505

ABSTRACT

Using green techniques to convert native starches into nanoparticles is an interesting approach to producing stabilizers for Pickering emulsions, aiming at highly stable emulsions in clean label products. Nanoprecipitation was used to prepare the Pickering starch nanoparticles, while ultrasound technique has been used to modulate the size of these nanoparticles at the same time as the emulsion was developed. Thus, the main objective of this study was to evaluate the stabilizing effect of cassava starch nanoparticles (SNP) produced by the nanoprecipitation technique combined with ultrasound treatment carried out in the presence of water and oil (more hydrophobic physicochemical environment), different from previous studies that carry out the mechanical treatment only in the presence of water. The results showed that the increased ultrasound energy input could reduce particle size (117.58 to 55.75 nm) and polydispersity (0.958 to 0.547) in aqueous dispersions. Subsequently, Pickering emulsions stabilized by SNPs showed that increasing emulsification (ultrasonication) time led to smaller droplet sizes and monomodal size distribution. Despite flocculation, long-term ultrasonication (6 and 9 min) caused little variation in the droplet size after 7 days of storage. The cavitation effects favored the interaction between oil droplets through weak attraction forces and particle sharing, favoring the Pickering stabilization against droplet coalescence. Our results show the potential to use only physical modifications to obtain nanoparticles that can produce coalescence-stable emulsions that are environmentally friendly.


Subject(s)
Emulsions , Manihot , Nanoparticles , Particle Size , Starch , Manihot/chemistry , Starch/chemistry , Emulsions/chemistry , Nanoparticles/chemistry , Water/chemistry , Sonication/methods , Flocculation
2.
Int J Mol Sci ; 25(14)2024 Jul 11.
Article in English | MEDLINE | ID: mdl-39062874

ABSTRACT

To analyze the mechanism of copper accumulation in the marine alga Ulva compressa, it was cultivated with 10 µM of copper, with 10 µM of copper and increasing concentrations of a sulfide donor (NaHS) for 0 to 7 days, and with 10 µM of copper and a concentration of the sulfide acceptor (hypotaurine) for 5 days. The level of intracellular copper was determined as well as the level of glutathione (GSH) and phytochelatins (PCs) and the expression of metallothioneins (UcMTs). The level of intracellular copper in the algae treated with copper increased at day 1, slightly increased until day 5 and remained unchanged until day 7. The level of copper in the algae cultivated with copper and 100 or 200 µM of NaHS continuously increased until day 7 and the copper level was higher in the algae cultivated with 200 µM of NaHS compared to 100 µM of NaHS. In contrast, the level of intracellular copper decreased in the algae treated with copper and hypotaurine. The level of intracellular copper did not correlate with the level of GSH or with the expression of UcMTs, and PCs were not detected in response to copper, or copper and NaHS. Algae treated with copper and with copper and 200 µM of NaHS for 5 days were visualized by TEM and the elemental composition of electrondense particles was analyzed by EDXS. The algae treated with copper showed electrondense particles containing copper and sulfur, but not nitrogen, and they were mainly located in the chloroplast, but also in the cytoplasm. The algae treated with copper and NaHS showed a higher level of electrondense particles containing copper and sulfur, but not nitrogen, and they were located in the chloroplast, and in the cytoplasm. Thus, copper is accumulated as copper sulfide insoluble particles, and not bound to GSH, PCs or UcMTs, in the marine alga U. compressa.


Subject(s)
Copper , Glutathione , Metallothionein , Phytochelatins , Sulfides , Ulva , Copper/metabolism , Ulva/metabolism , Ulva/drug effects , Phytochelatins/metabolism , Glutathione/metabolism , Metallothionein/metabolism , Sulfides/metabolism , Taurine/analogs & derivatives
3.
Heliyon ; 10(12): e33384, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39027447

ABSTRACT

This work presents an exhaustive visualization of the airflow expulsed by a person while breathing, talking, exhaling, and blowing inside a closed room wearing a disposable face mask like those used in hospitals for patient protection and those who care for them. An optical schlieren experimental arrangement was used to obtain some of the relevant physical characteristics of the airflow, such as its refractive index gradient, the distribution of temperature, and the associated velocity field for all the tests developed. We tested three face masks, one of the surgical types and the others of the N95 series with denominations KN95 and 3MN95 (Aura TC-84A-8590). The results show appreciable differences between the masks evaluated; the surgical mask was the one that allowed the most abrupt output airflow through it in the field of view of the experimental setup. However, were also found some differences in the performance of the KN95 and 3MN95 masks. The KN95 face mask had the best performance since it expulsed to its surroundings the lowest airflow with different physical properties to the input airflow. The results obtained are relevant since it was possible to estimate the expulsed airflow velocity as a function of the distance for every face mask tested, which allows for understanding its filtering capacity by restricting the flow of potential pathogens from the mouth or nose of one person to another. Undoubtedly, the airflow behavior determination around a face mask can help to reduce the risk of spreading infectious airborne particles.

4.
Chemosphere ; 363: 142881, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39032733

ABSTRACT

This work explores the efficiency of honey bees (Apis mellifera) as biosamplers of metal pollution. To understand this, we selected two cities with different urbanization (a medium-sized city and a megacity), and we collected urban dust and honey bees captured during flight. We sampled two villages and a university campus as control areas. The metal content in dust was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Atomic Force Microscopy (AFM) and Scanning electron microscopy (SEM) were used to investigate the shape and size distribution of the particles, and to characterize the semiquantitative chemical composition of particles adhered to honey bee's wings. Principal Component Analysis (PCA) shows a distinctive urban dust geochemical signature for each city, with component 1 defining V-Cr-Ni-Tl-Pt-Pb-Sb as characteristic of Mexico City and Ce-As-Zr for dust from Hermosillo. Particle count using SEM indicates that 69% and 63.4% of the resuspended dust from Hermosillo and Mexico City, respectively, corresponds to PM2.5. Instead, the particle count measured on the honey bee wings from Hermosillo and Mexico City is mainly PM2.5, 91.4% and 88.9%, respectively. The wings from honey bees collected in the villages and the university campus show much lower particle amounts. AFM-histograms confirmed that the particles identified in Mexico City have even smaller sizes (between 60 and 480 nm) than those in Hermosillo (between 400 and 1400 nm). Particles enriched in As, Zr, and Ce mixed with geogenic elements such as Si, Ca, Mg, K, and Na dominate honey bee' wings collected in Hermosillo. In contrast, those particles collected from Mexico City contain V, Cr, Ni, Tl, Pt, Pb, and Sb. Such results agree with the urban dust data. This work shows that honey bees are suitable biosamplers for the characterization of fine dust fractions by microscopy techniques and reflect the urban pollution of the sites.


Subject(s)
Cities , Dust , Environmental Monitoring , Particulate Matter , Bees , Animals , Mexico , Particulate Matter/analysis , Dust/analysis , Air Pollutants/analysis , Particle Size , Urbanization , Metals/analysis
5.
Methods Mol Biol ; 2829: 227-235, 2024.
Article in English | MEDLINE | ID: mdl-38951338

ABSTRACT

Virus-like particles (VLPs) of the adeno-associated virus (AAV) can be produced using the baculovirus expression vector system. Insertion of small peptides on the surface of the AAV or AAV VLPs has been used to redirect the AAV to different target tissues and for vaccine development. Usually, the VLPs self-assemble intracellularly, and an extraction step must be performed before purification. Here, we describe the method we have used to extract AAV VLPs from insect cells successfully with peptide insertions on their surface.


Subject(s)
Dependovirus , Peptides , Dependovirus/genetics , Animals , Peptides/chemistry , Peptides/genetics , Genetic Vectors/genetics , Virion/genetics , Baculoviridae/genetics , Sf9 Cells , Humans , Cell Line , Capsid Proteins/genetics , Capsid Proteins/isolation & purification
6.
Methods Mol Biol ; 2829: 237-246, 2024.
Article in English | MEDLINE | ID: mdl-38951339

ABSTRACT

Virus-like particles (VLP) of the cowpea chlorotic mottle virus (CCMV), a plant virus, have been shown to be safe and noncytotoxic vehicles for delivering various cargos, including nucleic acids and peptides, and as scaffolds for presenting epitopes. Thus, CCMV-VLP have acquired increasing attention to be used in fields such as gene therapy, drug delivery, and vaccine development. Regardless of their production method, most reports purify CCMV-VLP through a series of ultracentrifugation steps using sucrose density gradient ultracentrifugation, which is a complex and time-consuming process. Here, the use of anion exchange chromatography is described as a one-step protocol for purification of CCMV-VLP produced by the insect cell-baculovirus expression vector system (IC-BEVS).


Subject(s)
Bromovirus , Bromovirus/genetics , Animals , Baculoviridae/genetics , Genetic Vectors/genetics , Chromatography, Ion Exchange/methods , Virion/isolation & purification , Virion/genetics , Virion/metabolism
7.
ACS Appl Bio Mater ; 7(7): 4642-4653, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38967050

ABSTRACT

Titanium-based implants have long been studied and used for applications in bone tissue engineering, thanks to their outstanding mechanical properties and appropriate biocompatibility. However, many implants struggle with osseointegration and attachment and can be vulnerable to the development of infections. In this work, we have developed a composite coating via electrophoretic deposition, which is both bioactive and antibacterial. Mesoporous bioactive glass particles with gentamicin were electrophoretically deposited onto a titanium substrate. In order to validate the hypothesis that the quantity of particles in the coatings is sufficiently high and uniform in each deposition process, an easy-to-use image processing algorithm was designed to minimize human dependence and ensure reproducible results. The addition of loaded mesoporous particles did not affect the good adhesion of the coating to the substrate although roughness was clearly enhanced. After 7 days of immersion, the composite coatings were almost dissolved and released, but phosphate-related compounds started to nucleate at the surface. With a simple and low-cost technique like electrophoretic deposition, and optimized stir and suspension times, we were able to synthesize a hemocompatible coating that significantly improves the antibacterial activity when compared to the bare substrate for both Gram-positive and Gram-negative bacteria.


Subject(s)
Anti-Bacterial Agents , Chitosan , Electrophoresis , Gentamicins , Glass , Materials Testing , Nanoparticles , Particle Size , Surface Properties , Titanium , Gentamicins/pharmacology , Gentamicins/chemistry , Titanium/chemistry , Titanium/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Glass/chemistry , Nanoparticles/chemistry , Chitosan/chemistry , Chitosan/pharmacology , Porosity , Microbial Sensitivity Tests , Humans , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Prostheses and Implants , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology
8.
J Photochem Photobiol B ; 258: 112979, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39003970

ABSTRACT

Bioluminescence resonance energy transfer photodynamic therapy, which uses light generated by bioluminescent proteins to activate photosensitizers and produce reactive oxygen species without the need for external irradiation, has shown promising results in cancer models. However, the characterization of delivery systems that can incorporate the components of this therapy for preferential delivery to the tumor remains necessary. In this work, we have characterized parvovirus B19-like particles (B19V-VLPs) as a platform for a photosensitizer and a bioluminescent protein. By chemical and biorthogonal conjugation, we conjugated rose Bengal photosensitizer and firefly luciferase to B19V-VLPs and a protein for added specificity. The results showed that B19V-VLPs can withstand decoration with all three components without affecting its structure or stability. The conjugated luciferase showed activity and was able to activate rose Bengal to produce singlet oxygen without the need for external light. The photodynamic reaction generated by the functionalized VLPs-B19 can decrease the viability of tumor cells in vitro and affect tumor growth and metastasis in the 4 T1 model. Treatment with functionalized VLPs-B19 also increased the percentage of CD4 and CD8 cell populations in the spleen and in inguinal lymph nodes compared to vehicle-treated mice. Our results support B19V-VLPs as a delivery platform for bioluminescent photodynamic therapy components to solid tumors.


Subject(s)
Photochemotherapy , Photosensitizing Agents , Rose Bengal , Animals , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Mice , Rose Bengal/chemistry , Rose Bengal/pharmacology , Rose Bengal/therapeutic use , Cell Line, Tumor , Humans , Singlet Oxygen/metabolism , Parvovirus B19, Human/drug effects , Parvovirus B19, Human/chemistry , Neoplasms/drug therapy , Luciferases, Firefly/metabolism , Female
9.
Chem Phys Lipids ; 263: 105418, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38944410

ABSTRACT

Cholesterol-rich nanoemulsion (LDE) can carry chemotherapeutic agents in the circulation and can concentrate those agents in the neoplastic and inflammatory tissues. This method improves the biodistribution of the drug and reduces toxicity. However, the structural stability of LDE particles, without or with associated drugs, has not been extensively investigated. The aim of the present study is to investigate the structural stability of LDE and LDE associated to paclitaxel, etoposide or methotrexate in aqueous solution over time by small-angle X-ray scattering (SAXS and Ultra SAXS) and dynamic light scattering (DLS). The results show that LDE and LDE associated with those chemotherapeutic agents had reproducible and stable particle diameter, physical structure, and aggregation behavior over 3-month observation period. As estimated from both DLS and Ultra-SAXS methods, performed at pre-established intervals, the average particle diameter of LDE alone was approx. 32 nm, of LDE-paclitaxel was 31 nm, of LDE-methotrexate was 35 nm and of LDE-etoposide was 36 nm. Ultra-SAXS analysis showed that LDE nanoparticles were quasi-spherical, and SAXS showed that drug molecules inside the particles showed a layered-like organization. Formulations of LDE with associated PTX, ETO or MTX were successfully tested in animal experiments and in patients with cancer or with cardiovascular disease, showing markedly low toxicity, good tolerability and possible superior pharmacological action. Our results may be useful for ensuing clinical trials of this novel Nanomedicine tool, by strengthening the knowledge of the structural aspects of those LDE formulations.


Subject(s)
Cholesterol , Emulsions , Methotrexate , Nanoparticles , Emulsions/chemistry , Cholesterol/chemistry , Nanoparticles/chemistry , Methotrexate/chemistry , Humans , Animals , Particle Size , Paclitaxel/chemistry , Paclitaxel/pharmacology , Scattering, Small Angle , Etoposide/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , X-Ray Diffraction , Molecular Structure
10.
Methods Mol Biol ; 2822: 387-410, 2024.
Article in English | MEDLINE | ID: mdl-38907930

ABSTRACT

Plant viruses such as brome mosaic virus and cowpea chlorotic mottle virus are effectively purified through PEG precipitation and sucrose cushion ultracentrifugation. Increasing ionic strength and an alkaline pH cause the viruses to swell and disassemble into coat protein subunits. The coat proteins can be reassembled into stable virus-like particles (VLPs) that carry anionic molecules at low ionic strength and through two-step dialysis from neutral pH to acidic buffer. VLPs have been extensively studied due to their ability to protect and deliver cargo, particularly RNA, while avoiding degradation under physiological conditions. Furthermore, chemical functionalization of the surface of VLPs allows for the targeted drug delivery. VLPs derived from plants have demonstrated great potential in nanomedicine by offering a versatile platform for drug delivery, imaging, and therapeutic applications.


Subject(s)
Plant Viruses , Plant Viruses/genetics , Capsid Proteins/chemistry , Capsid Proteins/genetics , Capsid Proteins/metabolism , Virion/chemistry , Virion/genetics , Bromovirus/chemistry , Bromovirus/genetics , RNA/chemistry , Hydrogen-Ion Concentration , RNA, Viral/genetics
11.
Vaccine ; 42(18): 3916-3929, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38782665

ABSTRACT

Nonenveloped virus-like particles (VLPs) are self-assembled oligomeric structures composed of one or more proteins that originate from diverse viruses. Because these VLPs have similar antigenicity to the parental virus, they are successfully used as vaccines against cognate virus infection. Furthermore, after foreign antigenic sequences are inserted in their protein components (chimVLPs), some VLPs are also amenable to producing vaccines against pathogens other than the virus it originates from (these VLPs are named platform or epitope carrier). Designing chimVLP vaccines is challenging because the immunogenic response must be oriented against a given antigen without altering stimulant properties inherent to the VLP. An important step in this process is choosing the location of the sequence modifications because this must be performed without compromising the assembly and stability of the original VLP. Currently, many immunogenic data and computational tools can help guide the design of chimVLPs, thus reducing experimental costs and work. In this study, we analyze the structure of a novel VLP that originate from an insect virus and describe the putative regions of its three structural proteins amenable to insertion. For this purpose, we employed molecular dynamics (MD) simulations to assess chimVLP stability by comparing mutated and wild-type (WT) VLP protein trajectories. We applied this procedure to design a chimVLP that can serve as a prophylactic vaccine against the SARS-CoV-2 virus. The methodology described in this work is generally applicable for VLP-based vaccine development.


Subject(s)
Epitopes , Vaccines, Virus-Like Particle , Vaccines, Virus-Like Particle/immunology , Epitopes/immunology , Epitopes/genetics , Humans , SARS-CoV-2/immunology , Molecular Dynamics Simulation , COVID-19/prevention & control , COVID-19/immunology , COVID-19 Vaccines/immunology , Computational Biology/methods
12.
Vaccines (Basel) ; 12(4)2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38675794

ABSTRACT

Previously, it was shown that intranasally (i.n.) administered Corynebacterium pseudodiphtheriticum 090104 (Cp) or CP-derived bacterium-like particles (BLPs) improve the immunogenicity of the pneumococcal conjugate vaccine (PCV). This work aimed to deepen the characterization of the adjuvant properties of Cp and CP-derived BLPs for their use in the development of pneumococcal vaccines. The ability of Cp and CP-derived BLPs to improve both the humoral and cellular specific immune responses induced by i.n. administered polysaccharide-based commercial pneumococcal vaccine (Pneumovax 23®) and the chimeric recombinant PSPF (PsaA-Spr1875-PspA-FliC) protein was evaluated, as well as the protection against Streptococcus pneumoniae infection in infant mice. Additionally, whether the immunization protocols, including Cp and CP-derived BLPs, together with the pneumococcal vaccines can enhance the resistance to secondary pneumococcal pneumonia induced after inflammatory lung damage mediated by the activation of Toll-like receptor 3 (TLR3) was assessed. The results showed that both Cp and CP-derived BLPs increased the immunogenicity and protection induced by two pneumococcal vaccines administered through the nasal route. Of note, the nasal priming with the PSPF T-dependent antigen co-administered with Cp or CP-derived BLPs efficiently stimulated humoral and cellular immunity and increased the resistance to primary and secondary pneumococcal infections. The CP-derived BLPs presented a stronger effect than live bacteria. Given safety concerns associated with live bacterium administration, especially in high-risk populations, such as infants, the elderly, and immunocompromised patients, BLPs emerge as an attractive mucosal adjuvant to improve the host response to pneumococcal infections and to enhance the vaccines already in the market or in development.

13.
Bone ; 184: 117090, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38579924

ABSTRACT

Mechanical properties are becoming fundamental for advancing the comprehension of cellular processes. This study addresses the relationship between viscoelastic properties and the cellular mineralization process. Osteoblast-like cells treated with an osteogenic medium were employed for this purpose. Additionally, the study explores the impact of hydroxyapatite (HA) and hydroxyapatite/silver (HA/Ag) composite on this process. AFM relaxation experiments were conducted to extract viscoelastic parameters using the Fractional Zener (FZ) and Fractional Kelvin (FK) models. Our findings revealed that the main phases of mineralization are associated with alterations in the viscoelastic properties of osteoblast-like cells. Furthermore, HA and HA/Ag treatments significantly influenced changes in the viscoelastic properties of these cells. In particular, the HA/Ag treatment demonstrated a marked enhancement in cell fluidity, suggesting a possible role of silver in accelerating the mineralization process. Moreover, the study underscores the independence observed between fluidity and stiffness, indicating that modifications in one parameter may not necessarily correspond to changes in the other. These findings shed light on the factors involved in the cellular mineralization process and emphasize the importance of using viscoelastic properties to discern the impact of treatments on cells.


Subject(s)
Calcification, Physiologic , Durapatite , Elasticity , Osteoblasts , Silver , Durapatite/chemistry , Osteoblasts/metabolism , Osteoblasts/drug effects , Osteoblasts/cytology , Silver/chemistry , Calcification, Physiologic/physiology , Calcification, Physiologic/drug effects , Viscosity , Cell Line , Humans , Microscopy, Atomic Force , Animals
14.
Polymers (Basel) ; 16(5)2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38475362

ABSTRACT

The goal of this research was to create an antibacterial biopolymeric coating integrating lytic bacteriophages against Salmonella enterica for use in ripened cheese. Salmonella enterica is the main pathogen that contaminates food products and the food industry. The food sector still uses costly and non-selective decontamination and disease control methods. Therefore, it is necessary to look for novel pathogen biocontrol technologies. Bacteriophage-based biocontrol seems like a viable option in this situation. The results obtained show promise for food applications since the edible packaging developed (EdiPhage) was successful in maintaining lytic phage viability while preventing the contamination of foodstuff with the aforementioned bacterial pathogen.

15.
Sci Total Environ ; 923: 171390, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38438044

ABSTRACT

Marine microdebris (MDs, <5 mm) and mesodebris (MesDs, 5-25 mm), consist of various components, including microplastics (MPs), antifouling or anticorrosive paint particles (APPs), and metallic particles (Mmps), among others. The accumulation of these anthropogenic particles in macroalgae could have significant implications within coastal ecosystems because of the role of macroalgae as primary producers and their subsequent transfer within the trophic chain. Therefore, the objectives of this study were to determine the abundance of MDs and MesDs pollution in different species of macroalgae (P. morrowii, C. rubrum, Ulva spp., and B. minima) and in surface waters from the Southwest Atlantic coast of Argentina to evaluate the ecological damage. MDs and MesDs were chemically characterized using µ-FTIR and SEM/EDX to identify, and assess their environmental impact based on their composition and degree of pollution by MPs, calculating the Polymer Hazard Index (PHI). The prevalence of MDs was higher in foliose species, followed by filamentous and tubular ones, ranging from 0 to 1.22 items/g w.w. for MPs and 0 to 0.85 items/g w.w. for APPs. It was found that macroalgae accumulate a higher proportion of high-density polymers like PAN and PES, as well as APPs based on alkyd, PMMA, and PE resins, whereas a predominance of CE was observed in surrounding waters. Potentially toxic elements, such as Cr, Cu, and Ti, were detected in APPs and MPs, along with the presence of epiplastic communities on the surface of APPs. According to PHI, the presence of high hazard score polymers, such as PAN and PA, increased the overall risk of MP pollution in macroalgae compared to surrounding waters. This study provided a baseline for MDs and MesDs abundance in macroalgae as well as understanding the environmental impact of this debris and their bioaccumulation in the primary link of the coastal trophic chain.


Subject(s)
Seaweed , Water Pollutants, Chemical , Plastics , Environmental Monitoring , Ecosystem , Argentina , Water Pollutants, Chemical/analysis , Microplastics
16.
Viruses ; 16(3)2024 02 21.
Article in English | MEDLINE | ID: mdl-38543688

ABSTRACT

Two novel members of the subfamily Betarhabdovirinae, family Rhabdoviridae, were identified in Brazil. Overall, their genomes have the typical organization 3'-N-P-P3-M-G-L-5' observed in mono-segmented plant-infecting rhabdoviruses. In aristolochia-associated cytorhabdovirus (AaCV), found in the liana aristolochia (Aristolochia gibertii Hook), an additional short orphan ORF encoding a transmembrane helix was detected between P3 and M. The AaCV genome and inferred encoded proteins share the highest identity values, consistently < 60%, with their counterparts of the yerba mate chlorosis-associated virus (Cytorhabdovirus flaviyerbamate). The second virus, false jalap virus (FaJV), was detected in the herbaceous plant false jalap (Mirabilis jalapa L.) and represents together with tomato betanucleorhabdovirus 2, originally found in tomato plants in Slovenia, a tentative new species of the genus Betanucleorhabdovirus. FaJV particles accumulate in the perinuclear space, and electron-lucent viroplasms were observed in the nuclei of the infected cells. Notably, distinct from typical rhabdoviruses, most virions of AaCV were observed to be non-enclosed within membrane-bounded cavities. Instead, they were frequently seen in close association with surfaces of mitochondria or peroxisomes. Unlike FaJV, AaCV was successfully graft-transmitted to healthy plants of three species of the genus Aristolochia, while mechanical and seed transmission proved unsuccessful for both viruses. Data suggest that these viruses belong to two new tentative species within the subfamily Betarhabdovirinae.


Subject(s)
Aristolochia , Mirabilis , Rhabdoviridae , Aristolochia/genetics , Mirabilis/genetics , Genome, Viral , Plants/genetics , Phylogeny , Plant Diseases
17.
Toxics ; 12(1)2024 Jan 21.
Article in English | MEDLINE | ID: mdl-38276727

ABSTRACT

The toxicological impact of airborne polluting ultrafine particles (UFPs, also classified as nanoparticles with average sizes of less than 100 nm) is an emerging area of research pursuing a better understanding of the health hazards they pose to humans and other organisms. Hemolytic activity is a toxicity parameter that can be assessed quickly and easily to establish part of a nanoparticle's behavior once it reaches our circulatory system. However, it is exceedingly difficult to determine to what extent each of the nanoparticles present in the air is responsible for the detrimental effects exhibited. At the same time, current hemolytic assessment methodologies pose a series of limitations for the interpretation of results. An alternative is to synthesize nanoparticles that model selected typical types of UFPs in air pollution and evaluate their individual contributions to adverse health effects under a clinical assay of osmotic fragility. Here, we discuss evidence pointing out that the absence of hemolysis is not always a synonym for safety; exposure to model nanopollutants, even at low concentrations, is enough to increase erythrocyte susceptibility and dysfunction. A modified osmotic fragility assay in combination with a morphological inspection of the nanopollutant-erythrocyte interaction allows a richer interpretation of the exposure outcomes. Membrane-nanoparticle interplay has a leading role in the vulnerability observed. Therefore, future research in this line of work should pay special attention to the evaluation of the mechanisms that cause membrane damage.

18.
Appl Microbiol Biotechnol ; 108(1): 160, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38252281

ABSTRACT

Virus-like particles (VLPs) are nanometric structures composed of structural components of virions, keeping most of the cellular recognition and internalization properties, but are non-infective as they are deprived of their genetic material. VLPs have been a versatile platform for developing vaccines by carrying their own or heterologous antigenic epitopes. Moreover, VLPs can also be used as nanovessels for encapsulating molecules with therapeutic applications, like enzymes, nucleic acids, and drugs. Parvovirus B19 (B19V) VLPs can be self-assembled in vitro from the denatured major viral particle protein VP2 by equilibrium dialysis. Despite its fair productivity, this process is currently a time-consuming task. Affinity chromatography is used as an efficient step for concentration and purification, but it is only sometimes seen as a method that facilitates the oligomerization of proteins. In this research, we report a novel approach for the in vitro assembly of B19V VLPs through the immobilization of the denatured VP2 into an immobilized metal affinity chromatography (IMAC) column, followed by the on-column folding and the final VLP assembly upon protein elution. This method is suitable for the fast production of B19V VLPs. KEY POINTS: • Biotechnological applications for inclusion bodies • Efficient single-step purification and immobilization strategies • Rapid VLP assembly strategy.


Subject(s)
Bacterial Proteins , Parvovirus B19, Human , Parvovirus B19, Human/genetics , Bacteria , Biotechnology , Chromatography, Affinity
19.
Int J Biol Macromol ; 256(Pt 2): 128418, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38029902

ABSTRACT

The objective of this study was to immobilize a recombinant ß-galactosidase (Gal) tagged with a cellulose-binding domain (CBD) onto a magnetic core-shell (CS) cellulose system. After 30 min of reaction, 4 U/capsule were immobilized (CS@Gal), resulting in levels of yield and efficiency exceeding 80 %. The optimal temperature for ß-galactosidase-CBD activity increased from 40 to 50 °C following oriented immobilization. The inhibitory effect of galactose decreased in the enzyme reactions catalyzed by CS@Gal, and Mg2+ increased the immobilized enzyme activity by 40 % in the magnetic CS cellulose system. The relative enzyme activity of the CS@Gal was 20 % higher than that of the soluble enzyme activity after 20 min at 50 °C. The CS support and CS@Gal capsules exhibited an average size of 8 ± 1 mm, with the structure of the shell (alginate-pectin-cellulose) enveloping and isolating the magnetic core. The immobilized ß-galactosidase-CBD within the magnetic CS cellulose system retained ∼80 % of its capacity to hydrolyze lactose from skim milk after 10 reuse cycles. This study unveils a novel and promising support for the oriented immobilization of recombinant ß-galactosidase using a magnetic CS system and a CBD tag. This support facilitates ß-galactosidase reuse and efficient separation, consequently enhancing the catalytic properties of the enzyme.


Subject(s)
Cellulose , Enzymes, Immobilized , Cellulose/chemistry , Enzymes, Immobilized/chemistry , Catalysis , beta-Galactosidase/chemistry , Magnetic Phenomena
20.
Anal Bioanal Chem ; 416(4): 861-872, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38062198

ABSTRACT

Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) based on micro/nanostructured materials with different natures has received increasing attention for the analysis of a wide variety of analytes. However, up to now, only a few studies have shown the application of simple platforms in MALDI-MS for the identification of intact proteins. The present work reports on the application of copper oxide particles (Cu2O PS), obtained by a greener route, in combination with low amounts of 2,5-dihydroxybenzoic acid (DHB) as a novel hybrid platform. The combined Cu2O PS@DHB matrix, containing only 2.5 mg mL-1 of particles and 10 mg mL-1 of DHB, was easily applicable in MALDI-MS without surface modification of target plates. Under optimal conditions, the analysis of intact proteins up to 150,000 Da was possible, including immunoglobulin G, bovine serum albumin, and cytochrome C with adequate spot-to-spot signal reproducibility (RSD < 10%). In addition, the analysis of glycopeptides from IgG digests was carried out to prove the multipurpose application of the Cu2O PS@DHB platform in the low m/z range (2500-3000 Da). From the obtained results, it can be concluded that the optical and surface properties of as-synthesized Cu2O PS are likely to be responsible for the superior performance of Cu2O PS@DHB in comparison with conventional matrices. In this sense, the proposed user-friendly methodology opens up the prospect for possible implementation in bioanalysis and diagnostic research.


Subject(s)
Copper , Glycopeptides , Hydroxybenzoates , Reproducibility of Results , Gentisates/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Proteins/analysis , Lasers , Oxides
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