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1.
Int J Radiat Biol ; : 1-13, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683196

RESUMO

PURPOSE: Gamma rays are the most widely exploited physical mutagen in plant mutation breeding. They are known to be involved in the development of more than 60% of global cowpea (Vigna unguiculata (L.) Walp.) mutant varieties. Nevertheless, the nature and type of genome-wide mutations induced by gamma rays have not been studied in cowpea and therefore, the present investigation was undertaken. MATERIALS AND METHODS: Genomic DNAs from three stable gamma rays-induced mutants (large seed size, small seed size and disease resistant mutant) of cowpea cultivar 'CPD103' in M6 generation along with its progenitor were used for Illumina-based whole-genome resequencing. RESULTS: Gamma rays induced a relatively higher frequency (88.9%) of single base substitutions (SBSs) with an average transition to transversion ratio (Ti/Tv) of 3.51 in M6 generation. A > G transitions, including its complementary T > C transitions, predominated the transition mutations, while all four types of transversion mutations were detected with frequencies over 6.5%. Indels (small insertions and deletions) constituted about 11% of the total induced variations, wherein small insertions (6.3%) were relatively more prominent than small deletions (4.8%). Among the indels, single-base indels and, in particular, those involving A/T bases showed a preponderance, albeit indels of up to three bases were detected in low proportions. Distributed across all 11 chromosomes, only a fraction of SBSs (19.45%) and indels (20.2%) potentially altered the encoded amino acids/peptides. The inherent mutation rate induced by gamma rays in cowpea was observed to be in the order of 1.4 × 10-7 per base pair in M6 generation. CONCLUSION: Gamma-rays with a greater tendency to induce SBSs and, to a lesser extent, indels could be efficiently and effectively exploited in cowpea mutation breeding.

2.
Pharmaceutics ; 16(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38675126

RESUMO

The COVID-19 pandemic has made clear the need for effective and rapid vaccine development methods. Conventional inactivated virus vaccines, together with new technologies like vector and mRNA vaccines, were the first to be rolled out. However, the traditional methods used for virus inactivation can affect surface-exposed antigen, thereby reducing vaccine efficacy. Gamma rays have been used in the past to inactivate viruses. We recently proposed that high-energy heavy ions may be more suitable as an inactivation method because they increase the damage ratio between the viral nucleic acid and surface proteins. Here, we demonstrate that irradiation of the influenza virus using heavy ion beams constitutes a suitable method to develop effective vaccines, since immunization of mice by the intranasal route with the inactivated virus resulted in the stimulation of strong antigen-specific humoral and cellular immune responses.

3.
Int J Radiat Biol ; 100(5): 678-688, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451191

RESUMO

PURPOSE: To provide an updated summary of recent advances in the application of gamma irradiation to elicit secondary metabolism and for induction of mutations in plant cell and organ cultures for the production of industrially important specialized metabolites (SMs). CONCLUSIONS: Research on the application of gamma radiation with plants has contributed a lot to microbial decontamination of seeds, and the promotion of physiological processes such as seed germination, seedling vigor, plant growth, and development. Various studies have demonstrated the influence of gamma rays on the morphology, physiology, and biochemistry of plants. Recent research efforts have also shown that low-dose gamma (5-100 Gy) irradiation can be utilized as an expedient solution to alleviate the deleterious effect of abiotic stresses and to obtain better yields of plants. Inducing mutagenesis using gamma irradiation has also evolved as a better option for inducing genetic variability in crops, vegetables, medicinal and ornamentals for their genetic improvement. Plant SMs are gaining increasing importance as pharmaceutical, therapeutic, cosmetic, and agricultural products. Plant cell, tissue, and organ cultures represent an attractive alternative to conventional methods of procuring useful SMs. Among the varied approaches the elicitor-induced in vitro culture techniques are considered an efficient tool for studying and improving the production of SMs. This review focuses on the utilization of low-dose gamma irradiation in the production of high-value SMs such as phenolics, terpenoids, and alkaloids. Furthermore, we present varied successful examples of gamma-ray-induced mutations in the production of SMs.


Assuntos
Raios gama , Células Vegetais , Metabolismo Secundário , Metabolismo Secundário/efeitos da radiação , Células Vegetais/metabolismo , Células Vegetais/efeitos da radiação
4.
Int J Biol Macromol ; 262(Pt 2): 130010, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336320

RESUMO

In this work, gamma irradiation was used to create bimetallic silver­copper oxide nanoparticles (Ag-CuO NPs) in an ecologically acceptable way using gum Arabic (GA) polymer as a capping and reducing agent. Bimetallic Ag-CuO NPs were investigated through UV-Vis. spectroscopy, HR-TEM, SEM, DLS, and XRD examinations. The potency of antimicrobial and antibiofilm activities against a few bacterial isolates and Candida sp. had been investigated. Clinical investigations of 30 cows and 20 buffaloes from different sites in Egypt's Sharkia governorate found ulcerative lesions on the mouth and interdigital region. The cytotoxic assay of the generated NPs on BHK-21 was examined. The bimetallic Ag-CuO NPs had an average diameter of 25.58 nm, and the HR-TEM results showed that they were spherical. According to our results, Ag-CuO NPs exhibited the highest antibacterial efficacy against S. aureus (26.5 mm ZOI), K. pneumoniae (26.0 mm ZOI), and C. albicans (28.5 mm ZOI). The growth of biofilms was also successfully inhibited through the application of Ag-CuO NPs by 88.12 % against S. aureus, 87.08 % against C. albicans, and 74.0 % against B. subtilis. The ulcers on the mouth and foot of diseased animals healed in 4-5 days and 1 week, respectively, following topical application of bimetallic Ag-CuO NPs. The results examined the potential protective effects of a dosage of 3.57 µg/mL on cells before viral infection (cell control). According to our research, bimetallic Ag-CuO NPs limit the development of the virus that causes foot-and-mouth disease (FMD). The reduction of a specific FMD virus's cytopathic impact (CPE) on cell development represented the inhibitory effect when compared to identical circumstances without pretreatment with bimetallic Ag-CuO NPs. Their remarkable antibacterial properties at low concentration and continued-phase stability suggest that they may find widespread use in a variety of pharmacological and biological applications, especially in the wound-healing process.


Assuntos
Anti-Infecciosos , Febre Aftosa , Nanopartículas Metálicas , Nanopartículas , Feminino , Animais , Bovinos , Prata/química , Cobre/química , Goma Arábica/farmacologia , Staphylococcus aureus , Biomassa , Antibacterianos/química , Bactérias , Anti-Infecciosos/farmacologia , Nanopartículas/química , Óxidos/farmacologia , Nanopartículas Metálicas/química
5.
J Hazard Mater ; 468: 133830, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38387180

RESUMO

The daunting effects of persistent organic pollutants on humans, animals, and the environment cannot be overemphasized. Their fate, persistence, long-range transport, and bioavailability have made them an environmental stressor of concern which has attracted the interest of the research community. Concerted efforts have been made by relevant organizations utilizing legislative laws to ban their production and get rid of them completely for the sake of public health. However, they have remained refractive in different compartments of the environment. Their bioavailability is majorly a function of different anthropogenic activities. Landfilling and incineration are among the earliest classical means of environmental remediation of waste; however, they are not sustainable due to the seepage of contaminants in landfills, the release of toxic gases into the atmosphere and energy requirements during incineration. Other advanced waste destruction technologies have been explored for the degradation of these recalcitrant pollutants; although, some are efficient, but are limited by high amounts of energy consumption, the use of organic solvents and hazardous chemicals, high capital and operational cost, and lack of public trust. Thus, this study has systematically reviewed different contaminant degradation technologies, their efficiency, and feasibility. Finally, based on techno-economic feasibility, non-invasiveness, efficiency, and environmental friendliness; radiation technology can be considered a viable alternative for the environmental remediation of contaminants in all environmental matrices at bench-, pilot-, and industrial-scale.


Assuntos
Poluentes Ambientais , Recuperação e Remediação Ambiental , Humanos , Animais , Poluentes Orgânicos Persistentes , Temperatura , Substâncias Perigosas , Tecnologia
6.
Polymers (Basel) ; 16(4)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38399929

RESUMO

Radiation chemistry presents a unique avenue for developing innovative polymeric materials with desirable properties, eliminating the need for chemical initiators, which can be potentially detrimental, especially in sensitive sectors like medicine. In this investigation, we employed a radiation-induced graft polymerization process with N-vinylcaprolactam (NVCL) to modify lignocellulosic membranes derived from Agave salmiana, commonly known as maguey. The membranes underwent thorough characterization employing diverse techniques, including contact angle measurement, degree of swelling, scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared-attenuated total reflectance spectroscopy (FTIR-ATR), nuclear magnetic resonance (CP-MAS 13C-NMR), X-ray photoelectron spectroscopy (XPS), and uniaxial tensile mechanical tests. The membranes' ability to load and release an antimicrobial glycopeptide drug was assessed, revealing significant enhancements in both drug loading and sustained release. The grafting of PNVCL contributed to prolonged sustained release by decreasing the drug release rate at temperatures above the LCST. The release profiles were analyzed using the Higuchi, Peppas-Sahlin, and Korsmeyer-Peppas models, suggesting a Fickian transport mechanism as indicated by the Korsmeyer-Peppas model.

7.
Plants (Basel) ; 13(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38337875

RESUMO

The development of adaptation strategies for crops under ever-changing climate conditions is a critically important food security issue. Studies of barley responses to ionising radiation showed that this evolutionarily ancient stress factor can be successfully used to identify molecular pathways involved in adaptation to a range of abiotic stressors. In order to identify potential molecular contributors to abiotic stress resilience, we examined the transcriptomic profiles of barley seedlings after exposure to γ-rays, electrons, and protons. A total of 553 unique differentially expressed genes with increased expression and 124 with decreased expression were detected. Among all types of radiation, the highest number of differentially expressed genes was observed in electron-irradiated samples (428 upregulated and 56 downregulated genes). Significant upregulation after exposure to the three types of radiation was shown by a set of ROS-responsive genes, genes involved in DNA repair, cell wall metabolism, auxin biosynthesis and signalling, as well as photosynthesis-related genes. Most of these genes are known to be involved in plant ROS-mediated responses to other abiotic stressors, especially with genotoxic components, such as heavy metals and drought. Ultimately, the modulation of molecular pathways of plant responses to ionising radiation may be a prospective tool for stress tolerance programmes.

8.
J Fluoresc ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38396147

RESUMO

Gamma rays, as hazardous nuclear radiation, necessitate effective and rapid detection methods. This paper introduces a low-cost, fast, and simple fluorescence method based on CdTe/CdS core/shell quantum dots for gamma-ray detection. CdTe/CdS quantum dots, subjected to gamma irradiation from a 60Co source under various conditions, were investigated to assess their fluorescence sensor capabilities. The obtained results showed that an increase in CdTe/CdS nanoparticle size was associated with decreased sensitivity, while a reduction in CdTe/CdS concentration correlated with increased sensitivity. To further validate the practicality of CdTe/CdS core/shell quantum dots in gamma-ray detection, the structural properties of the quantum dots were meticulously studied. Raman spectroscopy, X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) analysis were conducted before and after gamma-ray radiation. The results demonstrated the crystalline stability of CdTe/CdS core/shell quantum dots under gamma irradiation, highlighting their robust structural integrity. In conclusion, the experimental findings underscore the exceptional potential of CdTe/CdS quantum dots as an off-fluorescence probe for simple, low-cost, fast, and on-site detection of gamma rays. This research contributes to the advancement of efficient and practical methods for gamma-ray sensing in various applications.

9.
Naunyn Schmiedebergs Arch Pharmacol ; 397(1): 521-534, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37480487

RESUMO

The danger of ionizing radiation exposure to human health is a concern. Since its wide use in medicine and industry, the development of radioprotectors has been very significant. Adenosine exerts anti-inflammatory actions and promotes tissue protection and repair, by activating the P1 receptors (A1, A2A, A2B, and A3). Zebrafish (Danio rerio) is an appropriate tool in the fields of toxicology and pharmacology, including the evaluation of radiobiological outcomes and in the search for radioprotector agents. This study aims to evaluate the effect of adenosine in the toxicity induced by radiation in zebrafish. Embryos were treated with 1, 10, or 100 µM adenosine, 30 min before the exposure to 15 Gy of gamma radiation. Adenosine potentiated the effects of radiation in heart rate, body length, and pericardial edema. We evaluated oxidative stress, tissue remodeling and inflammatory. It was seen that 100 µM adenosine reversed the inflammation induced by radiation, and that A2A2 and A2B receptors are involved in these anti-inflammatory effects. Our results indicate that P1R activation could be a promising pharmacological strategy for radioprotection.


Assuntos
Adenosina , Peixe-Zebra , Humanos , Animais , Adenosina/farmacologia , Raios gama/efeitos adversos , Frequência Cardíaca , Anti-Inflamatórios
10.
Int J Radiat Biol ; 100(2): 296-315, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37734005

RESUMO

PURPOSE: The North-western Himalayan region requires unique varietal traits for the cultivation and quality of grain produced. Wheat varieties released for this zone in the past remained very popular among the farmers. However, with the passage of time certain traits such as the appearance of pathogenic rust races and grain softness have become threat to the fecundity of these genotypes and needs immediate improvement in this region. Mutation breeding facilitates improving one or two traits of a popular cultivar and to generate variability for most of plant traits upon which selection can be imposed. The purpose of this study is to evaluate the mutagenic sensitivity, effectiveness and efficiency of physical and chemical mutagens in four bread wheat varieties with differential grain texture. MATERIALS AND METHODS: Four bread wheat varieties; HS 490, HPW 89, HPW 360 and HPW 251 were irradiated using six doses of gamma rays (γ-rays) ranging from 175 to 300 Gy; Co60 source (BARC, Mumbai, India) and six doses of ethyl methane sulfonate (EMS) ranging from 0.3 to 1.3%; EMS (Sigma-Aldrich, Bangalore, India) to assess their mutation sensitivity, effectiveness, efficiency and spectrum of induced macro-mutations in M1 and M2 generation. RESULTS: Based on mutagen sensitivity tests, both gamma rays and ethyl methane sulfonate had similar effects as the doses/concentrations increased in all four varieties. Ethyl methane sulfonate had a discernible effect on seed germination and growth parameters as compared to gamma irradiated treatments. Pollens viability studies confirmed the differential effects of both mutagens on germination and plant survivability. The LD50 and LC50 values varied between 290-315 Gy for gamma rays and 0.90-1.35% for EMS under controlled laboratory conditions, however, the range substantially differs for gamma rays (240-290 Gy) and for EMS (0.50-1.1%) under field conditions, irrespective of the variety treated. The frequency of chlorophyll mutations was low and showed a linear correlation with the doses/concentrations of the mutagen. A total of 117 putative mutants with desirable agro-morphological characteristics were also isolated. Mutagenic effectiveness and efficiency results showed that gamma irradiation doses of 250-300 Gy and ethyl methane sulfonate of 0.7-1.3% were most potent for an effective mutation breeding programme in wheat crop. CONCLUSIONS: It was found that semi-hard textured varieties showed higher sensitivity to chemical mutagens as compared to soft-textured varieties. Gamma irradiation dose of 250-300 Gy and ethyl methane sulfonate concentration of 0.7-1.3% were found to be most effective and efficient across four bread wheat varieties and can be used in large scale mutagenesis programmes.


Assuntos
Pão , Triticum , Triticum/genética , Raios gama , Índia , Metanossulfonato de Etila/farmacologia , Mutagênicos/farmacologia , Metano
11.
Adv Healthc Mater ; 13(3): e2301123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37921265

RESUMO

Studies on gamma radiation-induced injury have long been focused on hematopoietic, gastrointestinal, and cardiovascular systems, yet little is known about the effects of gamma radiation on the function of human cortical tissue. The challenge in studying radiation-induced cortical injury is, in part, due to a lack of human tissue models and physiologically relevant readouts. Here, a physiologically relevant 3D collagen-based cortical tissue model (CTM) is developed for studying the functional response of human iPSC-derived neurons and astrocytes to a sub-lethal radiation exposure (5 Gy). Cytotoxicity, DNA damage, morphology, and extracellular electrophysiology are quantified. It is reported that 5 Gy exposure significantly increases cytotoxicity, DNA damage, and astrocyte reactivity while significantly decreasing neurite length and neuronal network activity. Additionally, it is found that clinically deployed radioprotectant amifostine ameliorates the DNA damage, cytotoxicity, and astrocyte reactivity. The CTM provides a critical experimental platform to understand cell-level mechanisms by which gamma radiation (GR) affects human cortical tissue and to screen prospective radioprotectant compounds.


Assuntos
Amifostina , Humanos , Raios gama , Estudos Prospectivos , Dano ao DNA , Neurônios
12.
Philos Trans A Math Phys Eng Sci ; 382(2266): 20230082, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38104620

RESUMO

Many instruments for astroparticle physics are primarily geared towards multi-messenger astrophysics, to study the origin of cosmic rays and to understand high-energy astrophysical processes. Since these instruments observe the Universe at extreme energies and in kinematic ranges not accessible at accelerators these experiments provide also unique and complementary opportunities to search for particles and physics beyond the standard model of particle physics. In particular, the reach of IceCube, Fermi and KATRIN to search for and constrain Dark Matter, Axions, heavy Big Bang relics, sterile neutrinos and Lorentz invariance violation will be discussed. The contents of this article are based on material presented at the Humboldt-Kolleg 'Clues to a mysterious Universe-exploring the interface of particle, gravity and quantum physics' in June 2022. This article is part of the theme issue 'The particle-gravity frontier'.

14.
Front Plant Sci ; 14: 1266199, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37877080

RESUMO

Introduction: Future long-term space missions will focus to the solar system exploration, with the Moon and Mars as leading goals. Plant cultivation will provide fresh food as a healthy supplement to astronauts' diet in confined and unhealthy outposts. Ionizing radiation (IR) are a main hazard in outer space for their capacity to generate oxidative stress and DNA damage. IR is a crucial issue not only for human survival, but also for plant development and related value-added fresh food harvest. To this end, efforts to figure out how biofortification of plants with antioxidant metabolites (such as anthocyanins) may contribute to improve their performances in space outposts are needed. Methods: MicroTom plants genetically engineered to express the Petunia hybrida PhAN4 gene, restoring the biosynthesis of anthocyanins in tomato, were used. Seeds and plants from wild type and engineered lines AN4-M and AN4-P2 were exposed to IR doses that they may experience during a long-term space mission, simulated through the administration of gamma radiation. Plant response was continuously evaluated along life cycle by a non-disturbing/non-destructive monitoring of biometric and multiparametric fluorescence-based indices at both phenotypic and phenological levels, and indirectly measuring changes occurring at the primary and secondary metabolism level. Results: Responses to gamma radiation were influenced by the phenological stage, dose and genotype. Wild type and engineered plants did not complete a seed-to-seed cycle under the exceptional condition of 30 Gy absorbed dose, but were able to cope with 0.5 and 5 Gy producing fruits and vital seeds. In particular, the AN4-M seeds and plants showed advantages over wild type: negligible variation of fluorimetric parameters related to primary metabolism, no alteration or improvement of yield traits at maturity while maintaining smaller habitus than wild type, biosynthesis of anthocyanins and maintained levels of these compounds compared to non-irradiated controls of the same age. Discussion: These findings may be useful in understanding phenotypic effects of IR on plant growth in space, and lead to the exploitation of new breeding efforts to optimize plant performances to develop appropriate ideotypes for future long-term space exploration extending the potential of plants to serve as high-value product source.

15.
Can J Physiol Pharmacol ; 101(12): 672-681, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37767909

RESUMO

Ionizing radiation (IR) activates several signaling pathways. This study shows the impact of acute low-dose IR on crucial cytokines involved in cell-mediated immunity. The immunomodulatory effects of 0.25 and 0.5 Gray (Gy) gamma rays and standard immunomodulatory drugs (cyclophosphamide) on blood counts and significant pro-inflammatory cytokines implicated in various inflammatory conditions were tested in 20 rats. Examined was the effect of acute low doses on critical cytokines, which could be utilized as an alternative to current immunosuppressive drugs. One day post-irradiation, serum levels of interferon-gamma (INF-γ), tumor necrosis factor-alpha, and interleukin-2/1-beta were measured. A 0.25 Gy exposure did not affect the detected cytokines or blood cell count compared to the nonirradiated group. On the other hand, 0.5 Gy raises the majority of the immunologically examined cytokines except for INF-γ. Except for INF-γ, cyclophosphamide reduces all of the cytokines examined. As a result, low-dose IR has a less negative influence on essential inflammatory cytokines, permitting its use. More research is needed to determine how low amounts could be used in different immunological disorders.


Assuntos
Citocinas , Radiação Ionizante , Ratos , Animais , Citocinas/metabolismo , Raios gama/efeitos adversos , Interferon gama , Ciclofosfamida/farmacologia , Relação Dose-Resposta à Radiação
16.
BMC Microbiol ; 23(1): 224, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587432

RESUMO

BACKGROUND: Bimetallic nanoparticles (BNPs) has drawn a lot of attention especially during the last couple of decades. A bimetallic nanoparticle stands for a combination of two different metals that exhibit several new and improved physicochemical properties. Therefore, the green synthesis and design of bimetallic nanoparticles is a field worth exploring. METHODS: In this study, we present a green synthesis of silver nanoparticles (Ag NPs), selenium (Se) NPs, and bimetallic Ag-Se NPs using Gamma irradiation and utilizing a bacterial filtrate of Bacillus paramycoides. Different Techniques such as UV-Vis., XRD, DLS, SEM, EDX, and HR-TEM, were employed for identifying the synthesized NPs. The antimicrobial and antibiofilm activities of both the Ag/Se monometallic and bimetallic Ag-Se NPs were evaluated against some standard microbial strains including, Aspergillus brasiliensis ATCC16404, Candida albicans ATCC10231, Alternaria alternate EUM108, Fusarium oxysporum EUM37, Escherichia coli ATCC11229, Bacillus cereus ATCC15442, Klebsiella pneumoniae ATCC13883, Bacillus subtilis ATCC15442, and Pseudomonas aeruginosa ATCC6538 as a model tested pathogenic microbes. The individual free radical scavenging potentials of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs were determined using the DPPH radical scavenging assay. The degradation of methylene blue (MB) dye in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was used to assess their photocatalytic behavior. RESULTS: According to the UV-Vis. spectrophotometer, the dose of 20.0 kGy that results in Ag NPs with the highest O.D. = 3.19 at 390 nm is the most effective dose. In a similar vein, the optimal dose for the synthesis of Se NPs was 15.0 kGy dose with O.D. = 1.74 at 460 nm. With a high O.D. of 2.79 at 395 nm, the most potent dose for the formation of bimetallic Ag-Se NPs is 15.0 kGy. The recorded MIC-values for Ag-Se NPs were 62.5 µg mL- 1, and the data clearly demonstrated that C. albicans was the organism that was most susceptible to the three types of NPs. The MIC value was 125 µg mL- 1 for both Ag NPs and Se NPs. In antibiofilm assay, 5 µg mL- 1 Ag-Se NPs inhibited C. albicans with a percentage of 90.88%, E. coli with a percentage of 90.70%, and S. aureus with a percentage of 90.62%. The synthesized NPs can be arranged as follows in decreasing order of antioxidant capacity as an antioxidant result: Ag-Se NPs > Se NPs > Ag NPs. The MB dye degradation in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was confirmed by the decrease in the measured absorbance (at 664 nm) after 20 min of exposure to sunlight. CONCLUSION: Our study provides insight towards the synthesis of bimetallic NPs through green methodologies, to develop synergistic combinatorial antimicrobials with possible applications in the treatment of infectious diseases caused by clinically and industrial relevant drug-resistant strains.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Selênio , Selênio/farmacologia , Antioxidantes/farmacologia , Prata/farmacologia , Escherichia coli , Raios gama , Staphylococcus aureus , Anti-Infecciosos/farmacologia , Azul de Metileno , Candida albicans , Biofilmes
17.
Appl Radiat Isot ; 200: 110982, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37597269

RESUMO

Polymer-carbon nanostructures have been used as gamma-ray dosimeters. The thickness of the sensitive volume material plays an important role in the determination of the dosimetry response. In this work, the thickness effect of a real-time dosimeter based on the Epoxy/Multi-walled carbon nanotube (MWCNT) nanocomposite was investigated. The amount of electrical percolation threshold (EPT) for Epoxy/MWCNT nanocomposite was initially simulated using the finite element method. Then, the 0.1 MWCNT wt% nanocomposite was fabricated using a solution method with three thicknesses of 1, 2, and 3 mm. FESEM images demonstrated a good dispersion state of the inclusions into the Epoxy matrix. The samples were irradiated by gamma-rays of Co-60 source over the dose rates of 25-166 mGy/min. In addition, dosimetric characteristics were performed, including linearity, bias-polarity, angular dependence, energy dependence, field size, and repeatability. Results revealed that with increasing the thickness, the dosimetry response was enhanced remarkably.

18.
Luminescence ; 38(9): 1597-1606, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37325972

RESUMO

A series of ZnB2 O4 phosphors doped with different concentrations of Eu and Dy (0.05 0.1, 0.2, 0.5, 1.0 mol%) and co-doped with Ce (1, 2, 5, 7, 10 mol%) respectively was prepared via the solid-state reaction technique and the thermoluminescence (TL) behaviour of gamma ray-irradiated samples was studied. The synthesized samples were irradiated with γ-rays for the dose range 0.03-1.20 kGy. The TL intensity variations with dose, dopant concentration, and the effect of co-doping were studied. The TL response curves for ZnB2 O4 :Eu3+ and ZnB2 O4 :Dy3+ , ZnB2 O4 :Eu3 ,Ce3+ and ZnB2 O4 :Dy3+ ,Ce3+ phosphor were observed. It was revealed that ZnB2 O4 :Eu3+ showed a linear TL behaviour for the dose 0.03-1.20 kGy and ZnB2 O4 :Dy3+ showed linearity for the gamma dose range 0.03-0.10 kGy. Furthermore, fading for all the samples was observed to be less than 10% for a storage period of 30 days. In addition to this, the trapping parameters, especially activation energies were evaluated using the Ilich method and the initial rise method. The activation energy values obtained from both methods were in complete agreement with each other.


Assuntos
Boratos , Metais Terras Raras , Disprósio , Zinco , Raios gama
19.
Foods ; 12(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37174383

RESUMO

Food irradiation is a proven method commonly used for enhancing the safety and quality of meat. This technology effectively reduces the growth of microorganisms such as viruses, bacteria, and parasites. It also increases the lifespan and quality of products by delaying spoilage and reducing the growth of microorganisms. Irradiation does not affect the sensory characteristics of meats, including color, taste, and texture, as long as the appropriate dose is used. However, its influence on the chemical and nutritional aspects of meat is complex as it can alter amino acids, fatty acids, and vitamins as well as generate free radicals that cause lipid oxidation. Various factors, including irradiation dose, meat type, and storage conditions, influence the impact of these changes. Irradiation can also affect the physical properties of meat, such as tenderness, texture, and water-holding capacity, which is dose-dependent. While low irradiation doses potentially improve tenderness and texture, high doses negatively affect these properties by causing protein denaturation. This research also explores the regulatory and public perception aspects of food irradiation. Although irradiation is authorized and controlled in many countries, its application is controversial and raises concerns among consumers. Food irradiation is reliable for improving meat quality and safety but its implication on the chemical, physical, and nutritional properties of products must be considered when determining the appropriate dosage and usage. Therefore, more research is needed to better comprehend the long-term implications of irradiation on meat and address consumer concerns.

20.
Int J Mol Sci ; 24(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240171

RESUMO

Soybean (Glycine max (L.) Merr.) is a nutritious crop that can provide both oil and protein. A variety of mutagenesis methods have been proposed to obtain better soybean germplasm resources. Among the different types of physical mutagens, carbon-ion beams are considered to be highly efficient with high linear energy transfer (LET), and gamma rays have also been widely used for mutation breeding. However, systematic knowledge of the mutagenic effects of these two mutagens during development and on phenotypic and genomic mutations has not yet been elucidated in soybean. To this end, dry seeds of Williams 82 soybean were irradiated with a carbon-ion beam and gamma rays. The biological effects of the M1 generation included changes in survival rate, yield and fertility. Compared with gamma rays, the relative biological effectiveness (RBE) of the carbon-ion beams was between 2.5 and 3.0. Furthermore, the optimal dose for soybean was determined to be 101 Gy to 115 Gy when using the carbon-ion beam, and it was 263 Gy to 343 Gy when using gamma rays. A total of 325 screened mutant families were detected from out of 2000 M2 families using the carbon-ion beam, and 336 screened mutant families were found using gamma rays. Regarding the screened phenotypic M2 mutations, the proportion of low-frequency phenotypic mutations was 23.4% when using a carbon ion beam, and the proportion was 9.8% when using gamma rays. Low-frequency phenotypic mutations were easily obtained with the carbon-ion beam. After screening the mutations from the M2 generation, their stability was verified, and the genome mutation spectrum of M3 was systemically profiled. A variety of mutations, including single-base substitutions (SBSs), insertion-deletion mutations (INDELs), multinucleotide variants (MNVs) and structural variants (SVs) were detected with both carbon-ion beam irradiation and gamma-ray irradiation. Overall, 1988 homozygous mutations and 9695 homozygous + heterozygous genotype mutations were detected when using the carbon-ion beam. Additionally, 5279 homozygous mutations and 14,243 homozygous + heterozygous genotype mutations were detected when using gamma rays. The carbon-ion beam, which resulted in low levels of background mutations, has the potential to alleviate the problems caused by linkage drag in soybean mutation breeding. Regarding the genomic mutations, when using the carbon-ion beam, the proportion of homozygous-genotype SVs was 0.45%, and that of homozygous + heterozygous-genotype SVs was 6.27%; meanwhile, the proportions were 0.04% and 4.04% when using gamma rays. A higher proportion of SVs were detected when using the carbon ion beam. The gene effects of missense mutations were greater under carbon-ion beam irradiation, and the gene effects of nonsense mutations were greater under gamma-ray irradiation, which meant that the changes in the amino acid sequences were different between the carbon-ion beam and gamma rays. Taken together, our results demonstrate that both carbon-ion beam and gamma rays are effective techniques for rapid mutation breeding in soybean. If one would like to obtain mutations with a low-frequency phenotype, low levels of background genomic mutations and mutations with a higher proportion of SVs, carbon-ion beams are the best choice.


Assuntos
Glycine max , Mutagênicos , Glycine max/genética , Mutação , Raios gama , Íons , Fenótipo , Carbono , Genômica
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