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1.
Physiol Mol Biol Plants ; 27(10): 2433-2446, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34566283

RESUMO

Exploding global population, rapid urbanization, salinization of soils, decreasing arable land availability, groundwater resources, and dynamic climatic conditions pose impending damage to our food security by reducing the grain quality and quantity. This issue is further compounded in arid and semi-arid regions due to the shortage of irrigation water and erratic rainfalls. Millets are gluten (a family of proteins)-free and cultivated all over the globe for human consumption, fuel, feed, and fodder. They provide nutritional security for the under- and malnourished. With the deployment of strategies like foliar spray, traditional/marker-assisted breeding, identification of candidate genes for the translocation of important minerals, and genome-editing technologies, it is now tenable to biofortify important millets. Since the bioavailability of iron and zinc has been proven in human trials, the challenge is to make such grains accessible. This review encompasses nutritional benefits, progress made, challenges being encountered, and prospects of enriching millet crops with essential minerals.

2.
Radiat Environ Biophys ; 58(1): 69-80, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30467642

RESUMO

Radiological accidents and nuclear terrorism pose an increased threat to members of the public who, following such an event, would need to be assessed for medical care by fast triage. Assay methods such as chromosome aberrations (CA), cytokinesis-block micronucleus (CBMN) and fluorescence in situ hybridization (FISH) techniques have been well established for dose estimation and their potential for handling more samples has also been proved with automation. However, culturing of lymphocytes is an inevitable step, which limits the potential of these markers for triage. In vitro analysis of gamma-H2AX (γ-H2AX), gene and microRNA (miRNA) markers do not require culturing of lymphocytes, and as such have been suggested as attractive tools for triage. Despite studies reporting in vitro dose-response curves, limited evidence is available evaluating the suitability of these assays in real situations. In this study, we have measured the absorbed dose using γ-H2AX, gene (GADD45A, FDXR, and CDKN1A) and miRNA-101 expression in blood samples of cancer patients (n = 20) who had undergone partial-body radiotherapy and compared with the derived equivalent whole-body doses (EWBD). The obtained results from all patients showed a significant (p < 0.05) increase of γ-H2AX foci in post-irradiated as compared to pre-irradiated samples. Moreover, estimated doses using γ-H2AX foci showed a correlation with the derived EWBD (r2 = 0.60, p = 0.0003) and was also shown to be dependent on the irradiated body volume. Consistent with γ-H2AX foci frequency, an increase in fold change expression of genes and miRNA-101 was observed. However, the estimated dose significantly varied among the subjects and showed poor correlation (r2 = 0.09, 0.04, 0.01 and 0.03 for GADD45A, FDXR, CDKN1A and miRNA-101, respectively) with EWBD. The overall results suggest that the established in vitro γ-H2AX assay is suitable for the detection of radiation exposure and can also provide an estimate of the dose in in vivo irradiated samples. The genes and miRNA-101 markers showed increased expression; nevertheless, there is a need for further improvements to measure doses accurately using these markers.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Histonas/sangue , MicroRNAs/genética , Neoplasias/radioterapia , Doses de Radiação , Proteínas de Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Relação Dose-Resposta à Radiação , Feminino , Humanos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/genética
3.
J Cell Biochem ; 119(12): 10143-10150, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30171708

RESUMO

Mutations in NPHS1 can lead to disruption of the filtration barrier and cause proteinuria in nephrotic syndrome (NS). The aim of the study was to evaluate NPHS1 mutations, its susceptibility to the disease, and their association in children with steroid-resistant NS; mutation frequency of 9% was observed in patients with steroid-resistant NS, of which, six mutations and two single-nucleotide polymorphisms observed in the study population were found to be novel.


Assuntos
Predisposição Genética para Doença , Proteínas de Membrana/genética , Síndrome Nefrótica/genética , Proteinúria/genética , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Humanos , Lactente , Masculino , Mutação , Síndrome Nefrótica/complicações , Síndrome Nefrótica/patologia , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Proteinúria/complicações , Proteinúria/patologia
4.
J Nanosci Nanotechnol ; 16(5): 4948-59, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483851

RESUMO

Green nanoparticle synthesis was achieved using environmentally acceptable plant extracts reducing and capping agents. The present study was based on assessments to the anticancer activities to determine the effect of synthesized silver nanoparticles (AgNPs) from three medicinal plants on human liver (HepG2) and prostate (PC3) cancer cell lines. The synthesis of AgNPs using Plumbago zeylanica (Pz), Semecarpus anacardium (Sa) and Terminalia arjuna (Ta) plant extracts in the reaction mixture was monitored by UV-visible spectroscopy. FTIR results clearly illustrated that the plant extracts containing prominent peaks of functional groups and biomolecules viz., tannins, phenols, flavonoids and triterpenoids those act as capping agents and involved in the stabilization of the synthesised silver nanoparticles. Synthesized AgNPs were spherical and cuboid in shape which is determined by SEM. Average size of the AgNPs were between 80-98, 60-95 and 34-70 nm for PzAgNPs, SaAgNPs and TaAgNPs, respectively. Further, the synthesized AgNPs were characterized by XRD, EDX, DLS and Zeta potential analysis. Moreover, the synthesized AgNPs exhibited a dose-dependent cytotoxicity against human liver and prostate cancer cell lines. The inhibitory concentration (IC50) values of HepG2, PC3 and Vero cells were found to be 70.97, 58.61, 96.41; 10.04, 42.77, 83.86; and 28.42, 41.78, 69.48 µg/ml for PzAgNPs, SaAgNPs and TaAgNPs at 48 h incubation. An induction of apoptosis was confirmed by DNA fragmentation, Hoechst, Rhodamine and AO/EtBr staining. The present results strongly suggested that the AgNPs synthesized using P. zeylanica, S. anacardium and T. arjuna extracts showed potential anticancer activity of HepG2 and PC3 cell lines.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Extratos Vegetais/administração & dosagem , Prata/administração & dosagem , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Masculino , Nanopartículas Metálicas/química , Nanocápsulas/administração & dosagem , Nanocápsulas/química , Extratos Vegetais/química , Prata/química
5.
Radiat Environ Biophys ; 55(3): 339-47, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27287768

RESUMO

Gamma-H2AX (γ-H2AX) assay is a marker to measure double-strand breaks in the deoxyribonucleic acid. Variables such as age, oxidative stress, temperature, genetic factors and inter-individual variation have been reported to influence the baseline γ-H2AX focus levels. Therefore, knowledge on baseline frequency of γ-H2AX foci in a targeted population would facilitate reliable radiation triage and dose estimation. The objective of the present study was to establish the baseline data using blood samples from healthy volunteers (n = 130) differing in age, occupation and lifestyle as well as from occupationally exposed health workers (n = 20). The γ-H2AX focus assay was performed using epifluorescence microscopy. In vitro dose-response curve for γ-H2AX foci was constructed in blood samples (n = 3) exposed to X-rays (30 min post-exposure). The mean γ-H2AX focus frequency obtained in healthy volunteers was 0.042 ± 0.001 and showed an age-related increase (p < 0.001). Significantly higher (p < 0.005) focus frequencies were observed in health workers (0.066 ± 0.005) than in healthy volunteers. A sub-group analysis did not show a significant (p > 0.1) difference in γ-H2AX focus frequency among sexes. Blood exposed in vitro to X-rays showed dose-dependent increase in γ-H2AX foci frequency (Y = 0.1902 ± 0.1363 + 2.9020 ± 0.3240 * D). Baseline frequency of γ-H2AX foci obtained from different age groups showed a significant (p < 0.01) influence on the dose-response coefficients. The overall results demonstrated that the γ-H2AX assay can be used as a reliable biomarker for radiation triage and estimating the radiation absorbed dose by considering variables such as age, occupation and lifestyle factors.


Assuntos
Histonas/metabolismo , Raios X , Adolescente , Adulto , Idoso , Relação Dose-Resposta à Radiação , Feminino , Pessoal de Saúde , Voluntários Saudáveis , Humanos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Doses de Radiação , Exposição à Radiação , Adulto Jovem
6.
Bull Environ Contam Toxicol ; 97(5): 721-727, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27650375

RESUMO

Absorption, accumulation and translocation of 12 trace elements in nine dominant mangrove plants in the Indian Sundarban Wetland revealed both organ-specific and site-specific characteristics. An overall enrichment of elements was recorded in rhizosediment, exceeding the prescribed effects range-low (ER-L) of consensus based sediment quality guidelines (SQGs) for Cu and Pb. Avicennia officinalis, A. alba, Ceriops decandra and Excoecaria agallocha exhibited unique potential for accumulating Al, Cd, Co, Cr, Cu, Ni, Mn and Zn and could be considered efficient accumulators. Maximum element accumulation in trunk bark (As 6.16, Cr 49.9, Co 2.67, Cu 91.00 and Zn 85.5 mg kg-1) and root/pneumatophore (Al 1000 and Fe 2430 mg kg-1) was recorded. Maximum bioconcentration factor (6.23) in A. officinalis and translocation factor (17.5 for Mn) in C. decandra distinguished their phytoremediation capacity. These halophytes could be used for trace element phytoremediation in stressed sites of Sundarban.


Assuntos
Biodegradação Ambiental , Oligoelementos/análise , Áreas Alagadas
7.
Cytometry A ; 87(12): 1138-46, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26305808

RESUMO

Measurement of γ-H2AX protein changes in the peripheral blood lymphocytes (PBL) of individuals exposed to ionizing radiation is a simple, sensitive, and rapid assay for radiation triage and early marker of dose estimation. The qualitative and quantitative measurements of the protein changes were examined using flow cytometry and microscopy. Whole blood and isolated lymphocytes were exposed in vitro between 0.1 and 5 Gy doses of (60) Co γ-radiation at a dose rate of 1 Gy/min. Radiation induced γ-H2AX foci frequency (n = 3) and relative fluorescence intensity (n = 7) in PBL was measured at 0.5 and 2 hrs postexposure. The observed dose response for γ-H2AX foci frequency at both time points, for whole blood and isolated lymphocytes did not show any significant (P > 0.05) differences. However, when compared with γ-H2AX foci frequency scored manually (microscopy), the semiautomated analysis (captured images) showed a better correlation (r(2) = 0.918) than that obtained with automated (Metafer) scoring (r(2) = 0.690). It is noteworthy to mention that, the γ-H2AX foci frequency quantified using microscopy showed a dose dependent increase up to 2 Gy and the relative fluorescence intensity (RFI) measured with flow cytometry revealed an increase up to 5 Gy in the PBL exposed in vitro. Moreover, a better correlation was observed between the γ-H2AX foci frequency obtained by manual scoring and RFI (r(2) = 0.910). Kinetic studies showed that the γ-H2AX foci remain more or less unchanged up to 4 hrs and reduces gradually over 48 hrs of postexposure at 37°C. Further, inter and intra-laboratory comparisons showed consistency in the scoring of γ-H2AX foci frequency by manual and semiautomated scoring. The overall results suggest that measurement of γ-H2AX (microscopy and flow cytometry) should be employed within 4 to 6 hrs for a reliable dosimetry either by sharing the work load between the laboratories or investing more manpower; however, triage can be possible even up to 48 hrs of postirradiation.


Assuntos
Raios gama , Histonas/metabolismo , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Adulto , Automação , Separação Celular , Radioisótopos de Cobalto , Feminino , Citometria de Fluxo , Fluorescência , Humanos , Cinética , Masculino
8.
Planta ; 240(1): 177-94, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24771023

RESUMO

The productivity of Brassica oilseeds is severely affected by its major pest: aphids. Unavailability of resistance source within the crossable germplasms has stalled the breeding efforts to derive aphid resistant cultivars. In this study, jasmonate-mediated host defense in Indian mustard Brassica juncea (L.) Czern. was evaluated and compared with regard to its elicitation in response to mustard aphid Lipaphis erysimi (Kalt.) and the defense elicitor methyl jasmonate (MeJ). Identification of jasmonate-induced unigenes in B. juncea revealed that most are orthologous to aphid-responsive genes, identified in taxonomically diverse plant-aphid interactions. The unigenes largely represented genes related to signal transduction, response to biotic and abiotic stimuli and homeostasis of reactive oxygen species (ROS), in addition to genes related to cellular and metabolic processes involved in cell organization, biogenesis, and development. Gene expression studies revealed induction of the key jasmonate biosynthetic genes (LOX, AOC, 12-OPDR), redox genes (CAT3 and GST6), and other downstream defense genes (PAL, ELI3, MYR, and TPI) by several folds, both in response to MeJ and plant-wounding. However, interestingly aphid infestation even after 24 h did not elicit any activation of these genes. In contrast, when the jasmonate-mediated host defense was elicited by exogenous application of MeJ the treated B. juncea plants showed a strong antibiosis effect on the infesting aphids and reduced the growth of aphid populations. The level of redox enzymes CAT, APX, and SOD, involved in ROS homeostasis in defense signaling, and several defense enzymes viz. POD, PPO, and PAL, remained high in treated plants. We conclude that in B. juncea, the jasmonate activated endogenous-defense, which is not effectively activated in response to mustard aphids, has the potential to reduce population growth of mustard aphids.


Assuntos
Acetatos/farmacologia , Afídeos/fisiologia , Ciclopentanos/farmacologia , Interações Hospedeiro-Parasita , Mostardeira/imunologia , Oxilipinas/farmacologia , Doenças das Plantas/imunologia , Reguladores de Crescimento de Plantas/farmacologia , Animais , Antioxidantes/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Mostardeira/efeitos dos fármacos , Mostardeira/genética , Análise de Sequência com Séries de Oligonucleotídeos , Imunidade Vegetal , Proteínas de Plantas/genética , Crescimento Demográfico , Espécies Reativas de Oxigênio/metabolismo , Análise de Sequência de DNA , Estresse Fisiológico , Transcriptoma
9.
Ecotoxicol Environ Saf ; 108: 249-57, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25103568

RESUMO

The present study was aimed at evaluating phytotoxicity of various concentrations of lead nitrate (0, 100, 200, 400, 600, 800 and 1000mgL(-1)) in Sesbania grandiflora. The seedling growth was significantly affected (46%) at 1000mgL(-1) lead (Pb) treatment. Accumulation of Pb content was high in root (118mgg(-1) dry weight) than in shoot (23mgg(-1) dry weight). The level of photosynthetic pigment contents was gradually increased with increasing concentrations of Pb. Malondialdehyde (MDA) content increased in both the leaves as well as roots at 600mgL(-1) Pb treatment and decreased at higher concentrations. The activity of antioxidative enzymes such as superoxide dismutase and peroxidase were positively correlated with Pb treatment while catalase and ascorbate peroxidase activities increased up to 600mgL(-1) Pb treatment and then slightly decreased at higher concentrations. Isozyme banding pattern revealed the appearance of additional isoforms of superoxide dismutase and peroxidase in Pb treated leaf tissues. Isozyme band intensity was more consistent with the respective changes in antioxidative enzyme activities. Random amplified polymorphic DNA results indicated that genomic template stability (GTS) was significantly affected based on Pb concentrations. The present results suggest that higher concentrations of Pb enhanced the oxidative damage by over production of ROS in S. grandiflora that had potential tolerance mechanism to Pb as evidenced by increased level of photosynthetic pigments, MDA content, and the level of antioxidative enzymes. Retention of high levels of Pb in root indicated that S. grandiflora has potential for phytoextracting heavy metals by rhizofiltration.


Assuntos
Antioxidantes/metabolismo , Chumbo/toxicidade , Malondialdeído/metabolismo , Nitratos/toxicidade , Pigmentos Biológicos/metabolismo , Sesbania/efeitos dos fármacos , Ascorbato Peroxidases/metabolismo , Biodegradação Ambiental , Catalase/metabolismo , Perfilação da Expressão Gênica , Genoma de Planta , Genômica , Inativação Metabólica , Chumbo/metabolismo , Chumbo/farmacocinética , Peroxidação de Lipídeos/efeitos dos fármacos , Nitratos/metabolismo , Nitratos/farmacocinética , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Sesbania/genética , Sesbania/metabolismo , Superóxido Dismutase/metabolismo
10.
Mutat Res ; 757(2): 114-9, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-23906726

RESUMO

To determine whether the bleomycin (BLM)-induced bystander response occurs in human brain glioblastoma (BMG-1) cells, the BMG-1 cells were exposed to two different concentrations of BLM. The co-culture methodology was adopted to study the in vitro bystander effects. DNA damage was measured using the micronucleus (MN) and γ-H2AX assays. Cytotoxicity was measured using the trypan blue assay. Cell cycle kinetics was analyzed using flow cytometry. The overall results did not show any significant increase in either genotoxicity or cytotoxicity or a delay in the cell cycle kinetics in BMG-1 bystander cells co-cultured with BLM-exposed cells, suggesting that BLM did not induce a bystander response in the BMG-1 cells. Furthermore, the MN results of the BLM-exposed BMG-1 cells co-cultured with unexposed bystander human lung adenocarcinoma (A549 and NCI-H460) cells and vice versa suggested that the BMG-1 cells do not secrete bystander signals but do respond to those signals. Analyzing the underlying mechanism and pathways involved in preventing the cells from secreting bystander signals will provide new insights that can be applied to inhibit these mechanisms in other cell types, thereby preventing and controlling the bystander response and genomic instability and increasing the therapeutic gain in chemotherapy.


Assuntos
Adenocarcinoma/metabolismo , Antibióticos Antineoplásicos/farmacologia , Bleomicina/farmacologia , Neoplasias Encefálicas/metabolismo , Efeito Espectador/efeitos dos fármacos , Glioblastoma/metabolismo , Neoplasias Pulmonares/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Antibióticos Antineoplásicos/uso terapêutico , Bleomicina/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Feminino , Instabilidade Genômica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Physiol Plant ; 143(4): 344-54, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21883253

RESUMO

Excessive application of phosphorus (P)-rich manures to agricultural lands often results in P-accumulation in soils leading to water pollution through runoffs and leaching. Use of suitable plant species that can extract and sequester excess P from soil into their biomass is an effective method of remediation of P-contaminated soils. Knowledge on the molecular responses of plants to high P-accumulation and tolerance is lacking. Therefore, a suppression subtractive hybridization (SSH) strategy was employed to identify and elucidate the pattern of gene expression related to P-tolerance and accumulation in cucumber (Cucumis sativus L.), a P-accumulator plant. RNA isolated from cucumber grown in high P was used for 'tester' cDNA synthesis and SSH library preparation. A total of 63 cDNAs were identified as showing upregulated expression in this plant in response to high P. No putative function could be assigned to 7 (11%) of the 63 upregulated high P-modulated genes and 11 expressed sequence tags (ESTs) (17%) did not match database entries. The remaining 45 ESTs were grouped into five functional classes. The majority of these ESTs belonged to three groups: 'metabolism', 'protein synthesis/degradation and signaling' and 'cell structure/cell wall'. Only six 'stress/defense'-related ESTs were identified from this library. The results of reverse northern blot analysis was further confirmed and validated through semi-quantitative RT-PCR carried out with representative ESTs identified in this study. The research reported here may contribute to a preliminary understanding of the high P-related gene expression in this P-accumulating plant.


Assuntos
Cucumis sativus/genética , Etiquetas de Sequências Expressas , Genes de Plantas , Fósforo/metabolismo , Adaptação Fisiológica , Cucumis sativus/metabolismo , DNA Complementar/genética , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , RNA de Plantas/genética , Análise de Sequência de DNA
12.
Int J Radiat Biol ; 97(5): 687-694, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33798020

RESUMO

PURPOSE: In the modern era of radiotherapy, use of conventional radiation modalities (based on γ-rays) is being replaced by high-energy linear accelerator-based X-rays. As a result of mishandling of equipment or mechanical errors, health workers can be exposed to these high-energy X-rays. Especially in the absence of personnel monitoring devices, biodosimetry with a lower energy X-ray calibration curve may not provide an acceptable dose estimate. Moreover, the relative biological effectiveness (RBE) value assigned for X-rays is the same (ONE) regardless of beam energy (V), employed in diagnosis, interventional medicine, and radiotherapy. Therefore, the purpose of the study is to examine the induced biological effects, measured through micronucleus (MN) formation, of X-rays of different energies (3 and 6 MV X-rays), and to investigate the RBE relative to 225 kVp X-rays. MATERIALS AND METHODS: Peripheral blood lymphocytes (PBLs) from healthy donors (n = 6), were irradiated with 225 kVp, 3 MV, and 6 MV energy X-rays and induced biological damage was quantified as MN formation using the cytokinesis blocked MN (CBMN) assay. RESULTS: The MN per cell in the X-irradiated samples for the three different X-ray energies showed a significant (p<.0001) dose-dependent increase, when compared to unexposed samples. Aberration frequencies obtained at the same dose for the three different energies showed significant (p<.05) difference for the MN per cell among the energy levels; however, the in vitro dose-response curve parameters (slope, intercept, and coefficient) did not show any significant differences. The estimated dose in the blinded sample was within the 95% confidence intervals of each of the calibration curves. However, overall, the 6 MV dose-response curve coefficients yielded the closest dose estimate to that of the true dose. The calculated RBE values at 5% induced MN for 3 and 6 MV LINAC X-rays were 2.0 ± 0.04 and 0.70 ± 0.01, respectively, and the average RBE for the complete dose-response curves were 1.13 ± 0.04 and 0.80 ± 0.02 relative to 225 kVp X-rays as standard radiation. CONCLUSION: The established dose-response curves obtained for PBL exposed to different energy levels of X-rays of 225 kVp, 3 MV, and 6 MV are ready to use for biological dosimetry purposes. The calculated RBE values for the higher energies of X-rays relative to 225 kVp X-rays in this study suggest that RBE of X-rays may not be equal to one, with the true value dependent on the beam energy, the dose and dose rate, and the endpoint investigated.


Assuntos
Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Eficiência Biológica Relativa , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Testes para Micronúcleos , Aceleradores de Partículas , Raios X
13.
Int J Radiat Biol ; 97(7): 888-905, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33970757

RESUMO

PURPOSE: In case of a mass-casualty radiological event, there would be a need for networking to overcome surge limitations and to quickly obtain homogeneous results (reported aberration frequencies or estimated doses) among biodosimetry laboratories. These results must be consistent within such network. Inter-laboratory comparisons (ILCs) are widely accepted to achieve this homogeneity. At the European level, a great effort has been made to harmonize biological dosimetry laboratories, notably during the MULTIBIODOSE and RENEB projects. In order to continue the harmonization efforts, the RENEB consortium launched this intercomparison which is larger than the RENEB network, as it involves 38 laboratories from 21 countries. In this ILC all steps of the process were monitored, from blood shipment to dose estimation. This exercise also aimed to evaluate the statistical tools used to compare laboratory performance. MATERIALS AND METHODS: Blood samples were irradiated at three different doses, 1.8, 0.4 and 0 Gy (samples A, C and B) with 4-MV X-rays at 0.5 Gy min-1, and sent to the participant laboratories. Each laboratory was requested to blindly analyze 500 cells per sample and to report the observed frequency of dicentric chromosomes per metaphase and the corresponding estimated dose. RESULTS: This ILC demonstrates that blood samples can be successfully distributed among laboratories worldwide to perform biological dosimetry in case of a mass casualty event. Having achieved a substantial harmonization in multiple areas among the RENEB laboratories issues were identified with the available statistical tools, which are not capable to advantageously exploit the richness of results of a large ILCs. Even though Z- and U-tests are accepted methods for biodosimetry ILCs, setting the number of analyzed metaphases to 500 and establishing a tests' common threshold for all studied doses is inappropriate for evaluating laboratory performance. Another problem highlighted by this ILC is the issue of the dose-effect curve diversity. It clearly appears that, despite the initial advantage of including the scoring specificities of each laboratory, the lack of defined criteria for assessing the robustness of each laboratory's curve is a disadvantage for the 'one curve per laboratory' model. CONCLUSIONS: Based on our study, it seems relevant to develop tools better adapted to the collection and processing of results produced by the participant laboratories. We are confident that, after an initial harmonization phase reached by the RENEB laboratories, a new step toward a better optimization of the laboratory networks in biological dosimetry and associated ILC is on the way.


Assuntos
Laboratórios , Radiometria , Aberrações Cromossômicas/efeitos da radiação , Humanos , Exposição à Radiação , Reprodutibilidade dos Testes
14.
Mol Biotechnol ; 41(1): 42-52, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18726169

RESUMO

In rubber tree (Hevea brasiliensis), tapping panel dryness (TPD) syndrome is considered as a complex physiological disorder which affects latex biosynthesis. To identify differentially expressed genes between healthy and TPD-affected trees, mRNA differential display reverse transcriptase polymerase chain reaction (DDRT-PCR) analysis was performed. We isolated 10 differentially expressed cDNA fragments of which one cDNA encoding a putative TOM20 like protein was identified. The cDNA (1,024 bp), corresponding to the HbTOM20 gene (H evea b rasiliensis Translocase of the Outer Mitochondrial Membrane), contained an open reading frame to code for 202 amino acid protein with a theoretical pI value of 9.5 and the calculated protein M (W) was 23.5 kDa. The predicted amino acid sequence contained conserved domains of TOM20 like proteins in the N-terminal. The protein HbTOM20 has 32% and 27% similarity to Populus TOM20 and Solanum TOM20, respectively. Both semi-quantitative RT-PCR and Northern blot results revealed that the HbTOM20 expression was significantly down-regulated in TPD-affected trees compared to healthy one. Accumulation of HbTOM20 mRNA transcripts was significantly higher in the bark tissues collected from healthy region than that of partially affected by TPD (partially dried) while barely detectable in completely TPD-affected area. Differential expression pattern was noticed in three rubber clones representing various degrees of TPD tolerance. These results suggest that down-regulation of HbTOM20 in TPD-affected trees may play an important role in alteration of mitochondrial metabolism resulting in impaired latex biosynthesis.


Assuntos
Genes de Plantas , Hevea/genética , Proteínas de Membrana Transportadoras/genética , Proteínas Mitocondriais/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Sequência de Bases , Regulação para Baixo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Hevea/metabolismo , Látex/biossíntese , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Dados de Sequência Molecular , Estresse Oxidativo , Casca de Planta/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência
15.
3 Biotech ; 8(1): 60, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29354371

RESUMO

Influence of cytokinins, silver nitrate (AgNO3) and auxins on plant regeneration from cucumber was investigated. The cotyledonary node explants were cultured on MS medium augmented with various concentrations (0.5-2.5 mg l-1) of 6-benzyl amino purine (BAP) and kinetin (KIN) for shoot bud induction. BAP at 1.5 mg l-1 was found to be the best concentration for induction of high frequency of multiple shoots (98.4%). Interestingly, maximum percent of multiple shoot regeneration (100%) as well as number of shoot buds (54.6 shoots/culture) was recorded on MS medium containing the combination of 4.5 mg l-1 AgNO3 and 1.5 mg l-1 BAP. Multiple shoot bud regeneration frequency as well as the number of shoots was positively correlated with the concentrations of AgNO3. Addition of silver nitrate in the medium not only enhanced the rate of multiple shoot bud regeneration but also elongation of shoot buds was observed. The highest percent of rooting (96.2%) was noticed on a medium containing the combination of indole 3-butyric acid (IBA), 1.5 mg l-1 and KIN 0.5 mg l-1. Acclimatized plantlets were successfully established in the field where the survival rate observed was 72%. The RAPD profiles of in vitro regenerated plants were found to be highly monomorphic and identical banding pattern with mother plant. DNA fingerprinting results confirmed that the tissue culture plantlets were found to be true-to-type. The present study describes efficient protocol for high frequency plant regeneration via adventitious shoot organogenesis in cucumber.

16.
Bioresour Technol ; 248(Pt B): 28-35, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28844689

RESUMO

The aim of this work was to study the performance of a compost/ceramic bead biofilter (6:4 v/v) for the removal of gas-phase toluene and xylene at different inlet loading rates (ILR). The inlet toluene (or) xylene concentrations were varied from 0.1 to 1.5gm-3, at gas flow rates of 0.024, 0.048 and 0.072m3h-1, respectively, corresponding to total ILR varying between 7 and 213gm-3h-1. Although there was mutual inhibition, xylene removal was severely inhibited by the presence of toluene than toluene removal by the presence of xylene. The biofilter was also exposed to transient variations such as prolonged periods of shutdown (30days) and shock loads to envisage the response and recuperating ability of the biofilter. The maximum elimination capacity (EC) for toluene and xylene were 29.2 and 16.4gm-3h-1, respectively, at inlet loads of 53.8 and 43.7gm-3h-1.


Assuntos
Compostagem , Tolueno , Xilenos , Poluentes Atmosféricos , Biodegradação Ambiental , Filtração
17.
J Photochem Photobiol B ; 167: 309-320, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28129629

RESUMO

Nanoparticle based drug delivery can rapidly improves the therapeutic potential of anti-cancer agents. The present study focused to evaluate the hepatoprotective activity of silver nanoparticles (AgNPs) synthesized using aqueous extracts of Andrographis paniculata leaves (ApAgNPs) and Semecarpus anacardium nuts (SaAgNPs) against diethylnitrosamine (DEN) induced liver cancer in mice model. The physico-chemical properties of synthesized AgNPs were characterized by Fourier transform infrared (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), X-ray Diffraction (XRD), Energy Dispersive X-ray (EDX) spectrum, Zeta potential and Dynamic Light Scattering (DLS) analysis. The surface plasmon resonance (SPR) absorption spectrum revealed a strong peak at 420nm for both SaAgNPs and ApAgNPs. FTIR results exhibited the presence of possible functional groups in the synthesized AgNPs. TEM analysis determined the hexagonal, and spherical shape of the synthesized silver nanoparticles. The XRD and SAED pattern confirmed the crystalline nature and crystalline size of the AgNPs. EDX result clearly showed strong silver signals in the range between 2 and 4keV. Zeta potential measurements indicated a sharp peak at -3.93 and -13.8mV for ApAgNPs and SaAgNPs, respectively. DLS measurement expressed the particle size distribution was 70 and 60nm for ApAgNPs and SaAgNPs, respectively. DEN (20mg/kg b.wt.) was subjected to induce liver cancer in mice for 8weeks and treated with biosynthesized silver nanoparticles. Interestingly, ApAgNPs and SaAgNPs treated DEN induced animal groups show a decreased level of aspartate amino transferase (AST), alanine amino transferase (ALT), serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) activity and elevated level of catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST) and superoxide dismutase (SOD) activity over untreated DEN control animals group. Histopathological investigation reveals decreased fat accumulation, appearance of binucleated cells in nanoparticle treated animals and showed mere normal cells induced by DEN. Argyrophilic nucleolar organiser region (AgNORs) had a significant decrease in number of acidic proteins and mast cells assay showed decrease of metachromatic cells in nanoparticles treated animal groups over control. Present results strongly suggest that biomolecule coated silver nanoparticles exposure showed potential hepatoprotective effect against DEN induced liver cancer and could be used as an effective anticancer nanodrug.


Assuntos
Carcinógenos/toxicidade , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/prevenção & controle , Fígado/efeitos dos fármacos , Nanopartículas Metálicas , Prata/química , Animais , Carcinogênese , Cristalografia por Raios X , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Nanopartículas Metálicas/química , Camundongos , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Sci Rep ; 7(1): 11430, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900233

RESUMO

The mechanism of gold nanoparticle formation and genes involved in such processes, especially Au transport in plants are not understood. Previous reports pointed to the probable role of COPT2 in Au transport based on the transcript accumulation of COPT2 under Au exposure. Here, we provide evidence revealing the additional role of COPT2 for Au mobilization in yeast and Arabidopsis. The COPT2 transcripts significantly accumulated in the root of Arabidopsis under Au exposure. The expression of COPT2 restores Cu uptake ability in ctr1Δctr3Δ mutants and leads to Au sensitivity in yeast, which is comparable to Cu in growth kinetics experiments. The metal measurement data showed that the Au level was increased in COPT2, expressing yeast cells compared to vector transformed control. The copt2 mutant of Arabidopsis displayed a similar growth pattern to that of Col-0 under Au treatment. However, a notable phenotypic difference was noticed in three-week-old plants treated with and without Au. Consistent with yeast, Au uptake was reduced in the copt2 mutant of Arabidopsis. Together, these results clearly reveal the Au uptake capability of COPT2 in yeast and Arabidopsis. This is the first report showing the potential role of any transporter towards uptake and accumulation of Au in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Transporte de Cátions/metabolismo , Membrana Celular/metabolismo , Ouro/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Transporte de Cátions/genética , Cobre/metabolismo , Desenvolvimento Vegetal , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas SLC31 , Leveduras/genética , Leveduras/metabolismo
19.
Mar Pollut Bull ; 124(2): 1078-1088, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-28187966

RESUMO

The study accentuated the trace metal accumulation and distribution pattern in individual organs of 13 native mangrove plants along with rhizosediments in the Indian Sundarban Wetland. Enrichment of the essential micronutrients (Mn, Fe, Zn, Cu, Co, Ni) was recorded in all plant organs in comparison to non-essential ones, such as Cr, As, Pb, Cd, Hg. Trunk bark and root/pneumatophore showed maximum metal accumulation efficiency. Rhizosediment recorded manifold increase for most of the trace metals than plant tissue, with the following descending order: Fe>Mn>Zn>Cu>Pb>Ni>Cr>Co>As>Cd>Hg. Concentrations of Cu, Ni, Pb and Hg were found to exceed prescribed sediment quality guidelines (SQGs) indicating adverse effect on adjacent biota. Both index of geoaccumulation (Igeo) and enrichment factor (EF) also indicated anthropogenic contamination. Based on high (>1) translocation factor (TF) and bioconcentration factor (BCF) values Sonneratiaapetala and Avicenniaofficinalis could be considered as potential accumulators, of trace metals.


Assuntos
Biodegradação Ambiental , Sedimentos Geológicos/química , Metais/metabolismo , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Biota , Monitoramento Ambiental , Índia , Mercúrio/metabolismo , Metais Pesados/análise
20.
Front Plant Sci ; 8: 633, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28484486

RESUMO

Titanium dioxide nanoparticles (nanotitania: TiO2NPs) are used in a wide range of consumer products, paints, sunscreens, and cosmetics. The increased applications lead to the subsequent release of nanomaterials in environment that could affect the plant productivity. However, few studies have been performed to determine the overall effects of TiO2NPs on edible crops. We treated tomato plants with 0.5, 1, 2, and 4 g/L TiO2NPs in a hydroponic system for 2 weeks and examined physiological, biochemical, and molecular changes. The dual response was observed on growth and photosynthetic ability of plants depending on TiO2NPs concentrations. Low concentrations (0.5-2 g/L) of TiO2NPs boosted growth by approximately 50% and caused significant increase in photosynthetic parameters such as quantum yield, performance index, and total chlorophyll content as well as induced expression of PSI gene with respect to untreated plants. The high concentration (4 g/L) affected these parameters in negative manner. The catalase and peroxidase activities were also elevated in the exposed plants in a dose-dependent manner. Likewise, exposed plants exhibited increased expressions of glutathione synthase and glutathione S-transferase (nearly threefold increase in both roots and leaves), indicating a promising role of thiols in detoxification of TiO2NPs in tomato. The elemental analysis of tissues performed at 0.5, 1, and 2 g/L TiO2NPs indicates that TiO2NPs transport significantly affected the distribution of essential elements (P, S, Mg, and Fe) in roots and leaves displaying about threefold increases in P and 25% decrease in Fe contents. This study presents the mechanistic basis for the differential responses of titanium nanoparticles in tomato, and calls for a cautious approach for the application of nanomaterials in agriculture. GRAPHICAL ABSTRACTMovement of nanotitania in plant tissues.

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