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1.
Mol Microbiol ; 121(1): 142-151, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38082498

RESUMO

Free-living organisms frequently encounter unfavorable abiotic environmental factors. Those who adapt and cope with sudden changes in the external environment survive. Desiccation is one of the most common and frequently encountered stresses in nature. On the contrary, ionizing radiations are limited to high local concentrations of naturally occurring radioactive materials and related anthropogenic activities. Yet, resistance to high doses of ionizing radiation is evident across the tree of life. The evolution of desiccation resistance has been linked to the evolution of ionizing radiation resistance, although, evidence to support the idea that the evolution of desiccation tolerance is a necessary precursor to ionizing radiation resistance is lacking. Moreover, the presence of radioresistance in hyperthermophiles suggests multiple paths lead to radiation resistance. In this minireview, we focus on the molecular aspects of damage dynamics and damage response pathways comprising protective and restorative functions with a definitive survival advantage, to explore the serendipitous genesis of ionizing radiation resistance.


Assuntos
Deinococcus , Radiação Ionizante , Tolerância a Radiação , Reparo do DNA
2.
J Neurosci ; 43(34): 6061-6083, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37532464

RESUMO

Exposure to elevated doses of ionizing radiation, such as those in therapeutic procedures, catastrophic accidents, or space exploration, increases the risk of cognitive dysfunction. The full range of radiation-induced cognitive deficits is unknown, partly because commonly used tests may be insufficiently sensitive or may not be adequately tuned for assessing the fine behavioral features affected by radiation. Here, we asked whether γ-radiation might affect learning, memory, and the overall ability to adapt behavior to cope with a challenging environment (cognitive/behavioral flexibility). We developed a new behavioral assay, the context discrimination Morris water maze (cdMWM) task, which is hippocampus-dependent and requires the integration of various contextual cues and the adjustment of search strategies. We exposed male mice to 1 or 5 Gy of γ rays and, at different time points after irradiation, trained them consecutively in spatial MWM, reversal MWM, and cdMWM tasks, and assessed their learning, navigational search strategies, and memory. Mice exposed to 5 Gy performed successfully in the spatial and reversal MWM tasks; however, in the cdMWM task 6 or 8 weeks (but not 3 weeks) after irradiation, they demonstrated transient learning deficit, decreased use of efficient spatially precise search strategies during learning, and, 6 weeks after irradiation, memory deficit. We also observed impaired neurogenesis after irradiation and selective activation of 12-week-old newborn neurons by specific components of cdMWM training paradigm. Thus, our new behavioral paradigm reveals the effects of γ-radiation on cognitive flexibility and indicates an extended timeframe for the functional maturation of new hippocampal neurons.SIGNIFICANCE STATEMENT Exposure to radiation can affect cognitive performance and cognitive flexibility - the ability to adapt to changed circumstances and demands. The full range of consequences of irradiation on cognitive flexibility is unknown, partly because of a lack of suitable models. Here, we developed a new behavioral task requiring mice to combine various types of cues and strategies to find a correct solution. We show that animals exposed to γ-radiation, despite being able to successfully solve standard problems, show delayed learning, deficient memory, and diminished use of efficient navigation patterns in circumstances requiring adjustments of previously used search strategies. This new task could be applied in other settings for assessing the cognitive changes induced by aging, trauma, or disease.


Assuntos
Hipocampo , Aprendizagem , Camundongos , Masculino , Animais , Hipocampo/fisiologia , Neurogênese/fisiologia , Cognição/fisiologia , Neurônios/fisiologia , Aprendizagem em Labirinto/fisiologia
3.
Microb Cell Fact ; 23(1): 68, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408972

RESUMO

Owing to the growing need for natural materials in different fields, studying melanin production from biological sources is imperative. In the current study, the extracellular melanin pigment was produced by the fungus Curvularia soli AS21 ON076460. The factors that affect the production of melanin were optimized by the Plackett-Burman design (P-BD). The effect of gamma irradiation on melanin productivity was investigated. The maximum melanin yield (3.376 mg/L) was elicited by a stimulus of gamma irradiation at 1.0 kGy. The results evoked that, Curvularia soli AS21 ON076460 melanin exhibited excellent antimicrobial activity against all tested bacteria and fungi. Klebsiella pneumoniae ATCC 13883 and P. digitatum were mostly affected by melanin registering the inhibition zone diameters of 37.51 ± 0.012 and 44.25 ± 0.214 mm, respectively. Moreover, Curvularia soli AS21 ON076460 melanin indicated a significant antiviral efficacy (77% inhibition) of Herpes simplex virus (HSV1). The melanin pigment showed antioxidant activities with IC50 of 42 ± 0.021 and 17 ± 0.02 µg/mL against DPPH and NO, respectively. Melanin had cytotoxic action against human breast cancer and skin cancer cell lines (Mcf7and A431) as well as exerting a low percentage of cell death against normal skin cell lines (Hfb4). Melanin was effective in wound management of human skin cells by 63.04 ± 1.83% compared with control (68.67 ± 1.10%). The novelty in the study is attributed to the possibility of using gamma rays as a safe method in small economic doses to stimulate melanin production from the fungi that have been isolated. In summary, melanin produced from fungi has significant biological activities that encourage its usage as a supportive medical route.


Assuntos
Fungos , Melaninas , Humanos , Raios gama , Fungos/metabolismo , Curvularia/metabolismo
4.
J Fluoresc ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530563

RESUMO

In this investigation, we explore the integration of lanthanides into Metal-Organic Frameworks (MOFs) to enable Near-Infrared (NIR) emission. Specifically, we focus on Lanthanide-Naphthalene Dicarboxylate based MOFs (Ln-MOFs), incorporating elements such as Praseodymium (Pr), Samarium (Sm), Dysprosium (Dy), and Erbium (Er). The synthesis of Ln-MOFs is achieved via the hydrothermal method. The structure, morphology, thermal stability, and luminescence properties of synthesized Ln-MOFs have been evaluated through different characterization techniques. Upon photoexcitation at 350 nm, Ln-MOFs show the emission in the Visible and NIR region. Further, the luminescence intensity of Ln-MOFs enhanced by 2-3 folds in the visible region and 6-8 folds in NIR region after exposing to Gamma irradiation at 150 kGy. Cytotoxic effect on the viability of MDA-MB 231 and MDA-MB 468 Triple negative breast cancer (TNBC) cells was evaluated by MTT assay. The results revealed that among all synthesized MOFs, Pr-MOF exhibited an aggressive cytotoxic effect. Additionally, analysis of phase-contrast microscopy data indicates that Pr-MOF induces alterations in the morphology of both MDA-MB 231 and MDA-MB 468 TNBC cells when compared to untreated controls. The findings in this study reveal the utilization of Ln-MOFs for studying cytotoxicity and highlight their ability to enhance near-infrared (NIR) emission when exposed to gamma radiation.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39279250

RESUMO

This study presents a novel approach to manage vaginal infections due to Candidiasis, utilizing a novel silver secnidazole nano-hybrid emulsion (Ag-Secn-NHE)-based probiotics and free Ag-Secn-NHE. Ag-Secn-NHE was prepared by simple homogenization‒ultrasonication technique and validated by using a ultraviolet‒visible scan, dynamic light scattering, transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy, and zeta potential. Saccharomyces cerevisiae (RCMB 002Y001) is the most effective probiotic-producing organism that demonstrates significant effects when combined with Ag-Secn-NHE. Ag-Secn-NHE-based probiotics showed significant antifungal effect compared to free Ag-Secn-NHE, silver nitrate, silver nanoparticles, secnidazole, secnidazole nanoemulsion, and commercial vaginal wash against multidrug-resistant vaginal pathogens. The highest inhibitory effect was achieved with Ag-Secn-NHE-based probiotic against Candida auris, Candida albicans, and Cryptococcus neoformans with minimal inhibitory concentration (MIC) 0.625 ± 0.002, 0.00625:1.25 ± 0.012 and 0.00625:1.25 ± 0.032 mg/mL, respectively, in comparison with Ag-Secn-NHE that show MIC at 0.00625:1.25 ± 0.612, 0.0125:2.5 ± 0.812, and 0.0125:2.5 ± 0.112 mg/mL (Ag:Secn). Ag-Secn-NHE-based- probiotic show minimum fungicidal concentration (MFC) at range from 2.5 to 20 mg/mL, wherever free Ag-Secn-NHE show MFC range from 5 to >20 mg/mL. Additionally, Ag-Secn-NHE-based probiotics have 75% inhibition of biofilm formation against C. auris and 60% inhibition of biofilm formation against both Cryptococcus neoformans and C. albicans in comparison with free Ag-Secn-NHE. Time-kill curves showed that the antifungal effect of Ag-Secn-NHE-based probiotics was fungistatic at 2MIC value after 4 h and after 16 h for Ag-Secn-NHE. TEM photographs showed that C. auris cells treated with Ag-Secn-NHE-based probiotic formula revealed severe deformations and distored ultrastructural changes. furthermore, results indicated that the Gamma radiation up to 15 kGy increases production of Ag-Secn-NHE in comparison with non-irradiated one.

6.
Int J Mol Sci ; 25(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39273325

RESUMO

Cosmic radiation experienced during space travel may increase the risk of cognitive impairment. While simulated galactic cosmic radiation (GCRsim) has led to memory deficits in wildtype (WT) mice, it has not been investigated whether GCRsim in combination with genetic risk factors for Alzheimer's disease (AD) worsens memory further in aging mice. Here, we investigated the central nervous system (CNS) effects of 0 Gy (sham) or 0.75 Gy five-ion GCRsim or 2 Gy gamma radiation (IRR) in 14-month-old female and male APPNL-F/NL-F knock-in (KI) mice bearing humanized ApoE3 or ApoE4 (APP;E3F and APP;E4F). As travel to a specialized facility was required for irradiation, both traveled sham-irradiated C57BL/6J WT and KI mice and non-traveled (NT) KI mice acted as controls for potential effects of travel. Mice underwent four behavioral tests at 20 months of age and were euthanized for pathological and biochemical analyses 1 month later. Fecal samples were collected pre- and post-irradiation at four different time points. GCRsim seemed to impair memory in male APP;E3F mice compared to their sham counterparts. Travel tended to improve cognition in male APP;E3F mice and lowered total Aß in female and male APP;E3F mice compared to their non-traveled counterparts. Sham-irradiated male APP;E4F mice accumulated more fibrillar amyloid than their APP;E3F counterparts. Radiation exposure had only modest effects on behavior and brain changes, but travel-, sex-, and genotype-specific effects were seen. Irradiated mice had immediate and long-term differences in their gut bacterial composition that correlated to Alzheimer's disease phenotypes.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Cognição , Radiação Cósmica , Camundongos Transgênicos , Animais , Feminino , Masculino , Radiação Cósmica/efeitos adversos , Camundongos , Cognição/efeitos da radiação , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Técnicas de Introdução de Genes , Camundongos Endogâmicos C57BL , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Modelos Animais de Doenças , Fatores Sexuais , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Humanos
7.
Molecules ; 29(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38792087

RESUMO

In this work, we present the modification of a medical-grade silicone catheter with the N-vinylimidazole monomer using the grafting-from method at room temperature and induced by gamma rays. The catheters were modified by varying the monomer concentration (20-100 vol%) and the irradiation dose (20-100 kGy). Unlike the pristine material, the grafted poly(N-vinylimidazole) chains provided the catheter with hydrophilicity and pH response. This change allowed for the functionalization of the catheters to endow it with antimicrobial features. Thus, the quaternization of amines with iodomethane and bromoethane was performed, as well as the immobilization of silver and ampicillin. The inhibitory capacity of these materials, functionalized with antimicrobial agents, was challenged against Escherichia coli and Staphylococcus aureus strains, showing variable results, where loaded ampicillin was amply better at eliminating bacteria.


Assuntos
Escherichia coli , Imidazóis , Silicones , Staphylococcus aureus , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Silicones/química , Imidazóis/química , Imidazóis/farmacologia , Catéteres/microbiologia , Testes de Sensibilidade Microbiana , Polivinil/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Ampicilina/química , Ampicilina/farmacologia , Raios gama
8.
Environ Geochem Health ; 46(2): 66, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329628

RESUMO

The radiation arising from naturally occurring radioactive materials (NORMs) is the foremost contributor to the collective dose received by the global population. The present study aims to measure the natural background radiation level and the associated gamma radiation dose in air in the Beldih apatite mine region of Purulia district, India. This study is primarily focused on the determination of 238U, 232Th and 40K activities in the sub-surface soil of the study area. The measurements were carried out using a High Purity Germanium (HPGe) detector-based gamma-ray spectrometer with a relative efficiency of 80%. To achieve uniformity in exposure estimations, radium equivalent activity has been calculated. Additionally, the internal hazard index, external hazard index, radioactivity level index and gamma dose rates have been evaluated to estimate the radiation hazard levels in the study area. The comparison of obtained concentrations and hazard indices with global data (UNSCEAR. (2008). Sources, effects and risks of ionizing radiation. United nations scientific committee on the effects of atomic radiation (report to the general assembly, with Annexes).) suggests that this region lies in a relatively high background radiation zone.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Tório/análise , Radioisótopos de Potássio/análise , Solo , Poluentes Radioativos do Solo/análise , Rádio (Elemento)/análise
9.
World J Microbiol Biotechnol ; 40(9): 258, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954148

RESUMO

The aim of the present study is to develop a pH-sensing biopolymer film based on the immobilization of red cabbage extract (RCE) within bacterial cellulose (BC) to detect contamination and gamma radiation exposure in cucumbers. The results obtained show a sensitivity to pH changes for RCE in its aqueous form and that incorporated within BC films (RCE-BC), both showed color change correlated to bacterial growth (R2 = 0.91), this was supported with increase in pH values from 2 to 12 (R2 = 0.98). RCE and RCE-BC exposure to gamma radiation (0, 2.5, 5, 10, 15, 20, 25 kGy) resulted in gradual decrease in color that was more evident in RCE aqueous samples. To sense bacterial contamination of cucumbers, the total count was followed at 0, 5, 10 and 15 days in cold storage conditions and was found to reach 9.13 and 5.47 log cfu/mL for non-irradiated and 2 kGy irradiated samples, respectively. The main isolates detected throughout this storage period were identified as Pseudomonas fluorescens, Erwinia sp. Pantoea agglomerans using matrix assisted laser desorption ionization-time of flight-ms (MALDI-TOF-MS). Bacterial growth in stored irradiated cucumbers was detected by color change within 5 and 10 days of storage, after which there was no evident change. This is very useful since contamination within the early days of storage cannot be sensed with the naked eye. This study is the first to highlight utilizing RCE and RCE-BC as eco-friendly pH-sensing indicator films for intelligent food packaging to detect both food contamination and gamma preservation for refrigerator stored cucumbers.


Assuntos
Brassica , Celulose , Cucumis sativus , Raios gama , Extratos Vegetais , Brassica/microbiologia , Brassica/química , Celulose/química , Cucumis sativus/microbiologia , Cucumis sativus/química , Cucumis sativus/efeitos da radiação , Concentração de Íons de Hidrogênio , Extratos Vegetais/química , Microbiologia de Alimentos , Bactérias/efeitos da radiação , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Embalagem de Alimentos/métodos , Contaminação de Alimentos/análise , Armazenamento de Alimentos , Irradiação de Alimentos/métodos , Contagem de Colônia Microbiana
10.
World J Microbiol Biotechnol ; 40(9): 264, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990244

RESUMO

Bentonite is an integral part of the engineered barrier system (EBS) in deep geological repositories (DGR) for nuclear waste, but its indigenous microorganisms may jeopardize long-term EBS integrity. To predict microbial activity in DGRs, it is essential to understand microbial reactions to the early hot phase of DGR evolution. Two bentonites (BCV and MX-80) with varied bentonite/water ratios and saturation levels (compacted to 1600 kg.m- 3 dry density/powder/suspension), were subjected to heat (90-150 °C) and irradiation (0.4 Gy.h- 1) in the long-term experiments (up to 18 months). Molecular-genetic, microscopic, and cultivation-based techniques assessed microbial survivability. Exposure to 90 °C and 150 °C notably diminished microbial viability, irrespective of bentonite form, with negligible impacts from irradiation or sample type compared to temperature. Bentonite powder samples exhibited microbial recovery after 90 °C heating for up to 6 months but not 12 months in most cases; exposure to 150 °C had an even stronger effect. Further long-term experiments at additional temperatures combined with the mathematical prediction of temperature evolution in DGR are recommended to validate the possible evolution and spatial distribution of microbially depleted zones in bentonite buffer around the waste canisters and refine predictions of microbial effects over time in the DGR.


Assuntos
Bactérias , Bentonita , Raios gama , Temperatura Alta , Viabilidade Microbiana , Bentonita/química , Viabilidade Microbiana/efeitos da radiação , Bactérias/classificação , Bactérias/efeitos da radiação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Resíduos Radioativos/análise , Microbiologia do Solo
11.
BMC Oral Health ; 24(1): 110, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238729

RESUMO

BACKGROUND: Diabetes is a common disease that cancer patients may suffer from and may aggravate side effects of radiotherapy. This study aimed to detect whether metformin and/or quercetin will improve gamma-irradiation induced tongue toxicity in diabetic rats. METHODS: 35 male albino rats were divided into five groups; NOR no streptozotocin, no radiation and no treatment was given, DR rats were subjected to streptozotocin then gamma-irradiation, DRM rats were subjected to streptozotocin then gamma-irradiation then metformin, DRQ rats were subjected to streptozotocin then gamma-irradiation then quercetin, DRMQ rats were subjected to streptozotocin then gamma-irradiation then metformin and quercetin. Rats were euthanized 24 h after last treatment dose. Mean blood glucose level was recorded. Tongue specimens were stained with H&E and CD68. Histomorphometric analysis of length, diameter and taste buds of lingual papillae and epithelial, keratin and lamina propria thickness and CD68 positive cells were calculated. RESULTS: Blood glucose level of DRMQ was significantly lower than DR, DRM and DRQ, whereas higher than NOR. Metformin or quercetin partially restored tongue structure, papillae length and diameter and tongue layers thickness. The ameliorative effect was superior when metformin and quercetin were used together. Diabetes and irradiation significantly increased number of CD68 positive macrophages in submucosa and muscles. Metformin or quercetin significantly reduced number of lingual macrophages with more noticeable effect for quercetin. Treatment with metformin and quercetin significantly decreased number of macrophages. CONCLUSIONS: Combined use of metformin and quercetin might help mitigate the harmful effects of radiotherapy and diabetes on lingual tissues.


Assuntos
Diabetes Mellitus Experimental , Metformina , Humanos , Ratos , Masculino , Animais , Quercetina/farmacologia , Quercetina/uso terapêutico , Metformina/farmacologia , Metformina/uso terapêutico , Glicemia , Diabetes Mellitus Experimental/tratamento farmacológico , Estreptozocina/uso terapêutico , Língua
12.
Angew Chem Int Ed Engl ; : e202415811, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289789

RESUMO

Regulating chemical drug's responsiveness to gamma radiation is crucial for achieving better therapeutic effects in cancer treatment. Most research focused on thermodynamic chemical structure design, while little attention was paid to kinetic regulate strategy, which possesses greater universality and security. In this study, we achieved a kinetic-based regulate strategy of gamma radiation reaction, through the construction of microphase environment during polymerization of polytelluoxane (PTeO). We designed hydrophobic segments forming large compound micelles (LCMs) assembly to create kinetically favorable higher concentration for radiation-induced reaction. It exhibited a > ten times higher responsiveness and, as far as we know, merely required a minimum dosage of 5 Gy for polymerization to occur. What's more, by taking advantages of the assembly change with Te-O hydrophilic segments and gamma radiation, polymerization became milder with lower polydispersity than previous methods. Such kinetic-based regulate strategy could offer a novel perspective on the design of radiation-responsive chemoradiotherapy and other radiation-induced chemical process.

13.
Plant Biotechnol J ; 21(9): 1745-1756, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37224108

RESUMO

Nuclear energy, already a practical solution for supplying energy on a scale similar to fossil fuels, will likely increase its footprint over the next several decades to meet current climate goals. Gamma radiation is produced during fission in existing nuclear reactors and thus the need to detect leakage from nuclear plants, and effects of such leakage on ecosystems will likely also increase. At present, gamma radiation is detected using mechanical sensors that have several drawbacks, including: (i) limited availability; (ii) reliance on power supply; and (iii) requirement of human presence in dangerous areas. To overcome these limitations, we have developed a plant biosensor (phytosensor) to detect low-dose ionizing radiation. The system utilizes synthetic biology to engineer a dosimetric switch into potato utilizing the plant's native DNA damage response (DDR) machinery to produce a fluorescent output. In this work, the radiation phytosensor was shown to respond to a wide range of gamma radiation exposure (10-80 Grey) producing a reporter signal that was detectable at >3 m. Further, a pressure test of the top radiation phytosensor in a complex mesocosm demonstrated full function of the system in a 'real world' scenario.


Assuntos
Ecossistema , Plantas , Humanos , Raios gama , Plantas/genética , Monitoramento Ambiental
14.
Expert Rev Proteomics ; 20(10): 221-246, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37752078

RESUMO

INTRODUCTION: Radiological/nuclear accidents, hostile military activity, or terrorist strikes have the potential to expose a large number of civilians and military personnel to high doses of radiation resulting in the development of acute radiation syndrome and delayed effects of exposure. Thus, there is an urgent need for sensitive and specific assays to assess the levels of radiation exposure to individuals. Such radiation exposures are expected to alter primary cellular proteomic processes, resulting in multifaceted biological responses. AREAS COVERED: This article covers the application of proteomics, a promising and fast developing technology based on quantitative and qualitative measurements of protein molecules for possible rapid measurement of radiation exposure levels. Recent advancements in high-resolution chromatography, mass spectrometry, high-throughput, and bioinformatics have resulted in comprehensive (relative quantitation) and precise (absolute quantitation) approaches for the discovery and accuracy of key protein biomarkers of radiation exposure. Such proteome biomarkers might prove useful for assessing radiation exposure levels as well as for extrapolating the pharmaceutical dose of countermeasures for humans based on efficacy data generated using animal models. EXPERT OPINION: The field of proteomics promises to be a valuable asset in evaluating levels of radiation exposure and characterizing radiation injury biomarkers.


Assuntos
Síndrome Aguda da Radiação , Contramedidas Médicas , Animais , Humanos , Proteômica/métodos , Síndrome Aguda da Radiação/diagnóstico , Síndrome Aguda da Radiação/tratamento farmacológico , Espectrometria de Massas/métodos , Biomarcadores
15.
Strahlenther Onkol ; 199(9): 862-868, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37479825

RESUMO

PURPOSE: The occurrence of acrocentric chromosome association (ACA) after radiation exposure is an interesting cytogenetic endpoint, known to show a dose-dependent increase in irradiated lymphocytes suggesting its potential use in radiation biodosimetry. Here, an attempt was made to study the complexity and correlation of the occurrence of ACA with dicentric chromosomes (DC) in lymphocytes exposed to gamma radiation. METHODS: Ninety metaphases each with DC and without DC were chosen randomly from lymphocytes irradiated with different doses (0, 1, 2, 3, 4 and 5 Gy) of gamma radiation. ACA along with chromosomal types of aberrations were scored and analyzed for complexity and co-occurrence, retrospectively. RESULTS: The number of associations between 2 and ≥ 3 acrocentric chromosomes showed an increase with each irradiation dose. Concomitantly, the total number of chromosomal type of aberrations showed an increase in number at each radiation dose studied. The number of DC showed an increase, however, metaphases containing 1DC decreased while ≥ 2DC increased as the radiation dose increased. The number of tricentric chromosomes increased at doses higher than 2 Gy. Importantly, the association of DC with an acrocentric chromosome was noticed at doses 2 Gy and above. A significant (p < 0.05) increase was noticed in ACA frequency in 1DC and ≥ 2DC metaphases at 1 and 2 Gy, in 1DC at 3 Gy, and in ≥ 2DC 4 and 5 Gy compared to the frequency in no DC metaphases. When average ACA frequency was plotted against DC frequency, a significant (p = 0.0009) correlation was observed, producing regression equation y = 0.9025x + 0.1283; R2 = 0.9522. CONCLUSION: The present analysis showed increasing ACA complexity with increasing radiation dose. Furthermore, a higher frequency of ACA in cells with 1DC or ≥ 2DC compared to the ACA in cells without DC from the same sample of irradiated lymphocytes demonstrated the co-occurrence of ACA and DC in the same cells.


Assuntos
Linfócitos , Exposição à Radiação , Humanos , Estudos Retrospectivos , Cromossomos
16.
Biotechnol Appl Biochem ; 70(1): 306-317, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35481612

RESUMO

Based on the broad clinical utility of the immunosuppressant mycophenolic acid (MPA), this article aims to intensify the biosynthetic potential of Penicillium roqueforti for more effective hyperproduction of the drug. Several mutants were generated from irradiation mutagenesis and screened. Two strains (GM1013 and GM1093) presented an elevated MPA productivity with significant yield constancy over 10 subsequent generations. By investigating the effect of some phosphorous sources and mineral salts on MPA production by the two mutants, KH2 PO4 and FeSO4 ·7H2 O were most preferred by the two mutants for higher MPA production rates. Statistics-dependent experimental designs were also employed for optimizing medium components for maximum MPA production. Medium components were primarily screened using the Plackett-Burman model to demonstrate the most important components that most significantly affect MPA production. The concentrations of these significant components were then optimized through a central composite rotatable model. In conclusion, gamma-radiation mutation and response surface optimization resulted in a promising MPA productivity by P. roqueforti GM1013. To our knowledge, the MPA-yield achieved in this study (2933.32 mg L-1 ) is the highest reported by academic laboratories from P. roqueforti cultures, which could be of economic value for a prospective large industrialized application.


Assuntos
Ácido Micofenólico , Penicillium , Imunossupressores , Fermentação , Raios gama , Estudos Prospectivos , Penicillium/genética , Mutagênese
17.
Cell Biochem Funct ; 41(8): 1115-1132, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37653677

RESUMO

The biogenic synthesis of nanoparticles has drawn significant attention. The spleen is the largest lymphatic organ that is adversely impacted during irradiation. The current study was designated to evaluate the possible anti-inflammatory effect of matcha-silver nanoparticles (M-AgNPs) to reduce inflammation associated with γ-radiation induced-oxidative stress and inflammation in rats' spleen. Silver nanoparticles (AgNPs) were synthesized by biogenic synthesis using a green sonochemical method from matcha (M) green tea. The obtained M-AgNPs were extensively characterized by dynamic light scattering, transmission electron microscopy, thermogravimetric analysis, and Fourier-transform infrared spectroscopy. Using zetasizer analysis, the surface charge, particle size, and radical scavenging DPPH assay of M-AgNPs were also examined. Biocompatibility and cytotoxicity were analyzed by MTT assay, and the IC50 was calculated. Four groups of 24 Wistar rats each had an equal number of animals. The next step involved measuring the levels of oxidative stress markers in the rat splenic tissue. Additionally, the amounts of inflammatory protein expression were evaluated using the ELISA analysis. The results indicated the formation of spherical nanoparticles of pure Ag° coated with matcha polyphenols at the nanoscale, as well as uniform monodisperse particles suited for cellular absorption. Results revealed that M-AgNPs improved all biochemical parameters. Furthermore, M-AgNPs relieve inflammation by reducing the expression of NOD-like receptor family pyrin domain-containing 3 (NLRP3), interleukin-1ß (IL-1ß), and enhancing the levels of ileSnt information regulator 1 (SIRT1). Histopathological examinations demonstrated the ability of M-AgNPs to overcome the damage consequent to irradiation and recover the spleen's cellular structure. These results confirmed that matcha is a potential biomaterial for synthesizing AgNPs, which can be exploited for their anti-inflammatory activity.


Assuntos
Nanopartículas Metálicas , Prata , Animais , Ratos , Anti-Inflamatórios , Raios gama , Inflamação/tratamento farmacológico , Inflamação/patologia , Nanopartículas Metálicas/química , Estresse Oxidativo , Ratos Wistar , Transdução de Sinais , Prata/farmacologia , Prata/química , Prata/uso terapêutico , Sirtuína 1 , Baço , Lesões por Radiação/genética , Lesões por Radiação/metabolismo , Lesões por Radiação/prevenção & controle , Chá
18.
Can J Physiol Pharmacol ; 101(5): 226-234, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36812473

RESUMO

Many studies reported the diverse therapeutic potential of essential oils. They have a crucial role in cancer prevention and treatment. Antioxidant, antimutagenic, and antiproliferative are mechanisms involved. Also, essential oils may enhance immune function and surveillance, induce enzymes, enhance detoxification, and modulate multidrug resistance. Hemp oil, obtained from Cannabis sativaL. seeds, is known for its health-enhancing properties and bioactivity. Adult female Swiss albino mice were injected with viable Ehrlich ascites carcinoma cells (2.5 × 106 cells/mouse), and then administered with hemp oil (20 mg/kg) daily for 10 consecutive days pre-, and then 10 days post-exposure to 6 Gy whole-body gamma irradiation. Hemp oil significantly increased Beclin1, VMP1, LC3, cytochrome c, and Bax. More interestingly, Hemp oil showed a significant decrease in Bcl2 and P13k either alone or in combination with γ radiation. Finally, this study documented the possible role of hemp oil in inducing two cell death types, autophagy and apoptosis, as it may be applied as an adjuvant in cancer treatment.


Assuntos
Cannabis , Neoplasias , Óleos Voláteis , Feminino , Animais , Camundongos , Raios gama , Transdução de Sinais
19.
Parasitol Res ; 122(6): 1283-1291, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36988683

RESUMO

Experimental toxoplasmosis is an excellent model for adaptive immune response. Gamma-irradiated tachyzoites or soluble tachyzoite antigen extracts (STag) induce protection against experimental toxoplasmosis in mice. Scavenger receptors recognize irradiated proteins, promote their entry into cells, and lead to antigen presentation. CD36 is a specific scavenger receptor involved in intracellular transport of free fatty acid (FFA), cellular recycling, and intracellular trafficking in lipid rafts outside the lysosomal pathways. CD36 is also associated with an altered immune response, as CD36-/- mice presented some immune defects in the cyst-forming Toxoplasma gondii. We studied T. gondii infection in CD36-/- mice, naïve or immunized, with irradiated T. gondii STags by investigating protection, antibody production, and primed macrophage transplantation. CD36-/- mice presented no resistance against the viable RH tachyzoites, even after immunization with gamma-irradiated STags that protected wild-type mice. The animals presented poor humoral responses to both immunogens despite adequate levels of serum immunoglobulins. CD36-/- mice failed to induce protection against virulent T. gondii infection with inadequate antibody production or an innate response. Irradiated antigens failed to induce antibodies in CD36-/- mice and only produced adequate levels of immunoglobulin G when transplanted with irradiated STag-primed wild-type macrophages. The CD36 pathway is necessary for humoral response against the irradiated antigen; however, several other pathways are also involved in mounting a humoral response against any antigen. CD36 is a multipurpose molecule for FFA and lipid transport, as well as for the immune response, and gamma radiation mimics the innate response by targeting irradiated antigens of this pathway.


Assuntos
Vacinas Protozoárias , Toxoplasma , Toxoplasmose , Animais , Camundongos , Antígenos de Protozoários/genética , Imunização , Macrófagos , Imunoglobulina G , Camundongos Endogâmicos BALB C , Anticorpos Antiprotozoários , Proteínas de Protozoários
20.
Ecotoxicol Environ Saf ; 255: 114779, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36924557

RESUMO

Biological rhythm refers to the internal regulation of various life activities of an organism, which are determined by the specific time structure sequences of each individual. Behavior rhythm is the most intuitive embodiment of biological rhythm. To study the effect of low dose radiation on behavioral rhythm, zebrafish (Danio rerio) was used as a model organism in this study. The early embryos of zebrafish were irradiated at doses of 0.01, 0.1, and 1 Gy to observe the changes in zebrafish development, circadian rhythm, key clock genes, related RNA and protein expression, and melatonin. The results revealed that 0.1 and 1 Gy radiation could lead to different degrees of telencephalic nerve cell apoptosis and the formation of vacuolar structures. 0.1 and 1 Gy radiation could reduce the hatching rate of zebrafish embryos at 72 hpf and delay embryo hatching. The analysis of circadian behavior at 120 hpf demonstrated that 1 Gy dose of radiation altered the circadian rhythm of zebrafish, as well as decreased the distance, amplitude, and phase of movement. RT-PCR analysis of the key clock genes (bmal1b, clock1a, per1b, per2, cry2, and nr1d1) involved in regulating circadian rhythm was performed. The results showed that 1 Gy radiation could interfere with the expression of clock genes in zebrafish embryos and upregulate bmal1b, clock1a, and per1b. Western blot experiments further verified the protein expression of key clock genes, bmal1b and clock. Detection of melatonin secretion at different time points over 24 h showed that radiation doses of 0.1 and 1 Gy could increase melatonin secretion. Based on these findings, it is speculated that a certain dose of radiation may affect melatonin secretion, which impacts the telencephalon structure and ontogeny of zebrafish, delays hatching, and changes the circadian rhythm. This effect is thought to be achieved through upregulating the expression of circadian rhythm genes, clock1a and per1b and related proteins, which may be responsible for the abnormal circadian rhythm caused by radiation.


Assuntos
Melatonina , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Melatonina/farmacologia , Ritmo Circadiano , RNA Mensageiro/metabolismo , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo
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