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1.
Sci Total Environ ; : 173334, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38763191

RESUMO

Electronic and electric waste (e-waste) management strategies often fall short in dealing with the plastic constituents of printed circuit boards (PCB). Some plastic materials from PCB, such as epoxy resins, may release contaminants, but neither potential environmental impact has been assessed nor mitigation strategies have been put forward. This study assessed the biodegradation of microplastics (1-2 mm in size) from PCB by the fungus Penicillium brevicompactum over 28 days, thus contributing to the discussion of mitigation strategies for decreasing the environmental impact of such plastics in the environment. The capacity of P. brevicompactum to induce microplastic fragmentation and degradation has been determined by the increased the number of smaller-sized particles and microplastic mass reduction (up to 75 % within 14 days), respectively. The occurrence of chain scission and oxidation of microplastics exposed to P. brevicompactum when compared with the control conditions (which occurred only after 28 days of exposure) can be observed. Furthermore, Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy performed in dried biomass put in evidence an increase in the absorption intensities in regions that could be attributed to functional groups associated with carbohydrates. The results underline the potential role of the genus Penicillium, particularly P. brevicompactum, in the biodegradation of microplastics from PCB, thus providing the basis for further exploration of its potential for e-waste bioremediation and research on the underlying mechanisms for sustainable approaches to mitigate e-waste pollution.

2.
Sci Total Environ ; 912: 169287, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38103621

RESUMO

The application of bio-based biodegradable mulch films in agriculture has raised environmental concerns regarding their potential impacts on adjacent freshwater ecosystems. This study investigated the biodegradation of microplastics derived from a bio-based biodegradable mulch (bio-MPs) and its acute and chronic ecotoxicity considering relevant scenarios (up to 200 and 250 mg/kg of sediment, using pristine and/or UV-aged particles), using the fungus Penicillium brevicompactum and the dipteran Chironomus riparius as model organisms, respectively, due to their ecological relevance in freshwater environments. Fourier-transform infrared spectroscopy analysis suggested changes in the fungus's carbohydrate reserves and bio-MP degradation through the appearance of low molecular weight esters throughout a 28 day biodegradation test. In a short-term exposure (48 h), C. riparius larvae exposed to pristine or UV-aged bio-MPs had up to 2 particles in their gut. Exposure to pristine bio-MPs decreased larval aerobic metabolism (<20 %) and increased neurotransmission (>15 %), whereas exposure to UV-aged bio-MPs activated larval aerobic metabolism (>20 %) and increased antioxidant defences (catalase activity by >30 % and glutathione-s-transferase by >20 %) and neurotransmission (>30 %). Longer-term (28-d) exposure to UV-aged bio-MPs did not affect larval survival and growth nor the dipteran's emergence but increased male numbers (>30 %) at higher concentrations. This study suggests that the selected agricultural bio-based mulch film is prone to biodegradation by a naturally occurring fungus. However, there is a potential for endocrine disruption in the case of prolonged exposures to UV-aged microplastics. This study emphasises the importance of further research to elucidate the potential ecological effects of these plastic products, to ensure effective management practices, and to establish new regulations governing their use.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Masculino , Microplásticos/toxicidade , Plásticos/toxicidade , Ecossistema , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Agricultura , Larva , Água Doce
3.
Sci Total Environ ; 904: 166232, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37574074

RESUMO

Disposable facemasks represent a new form of environmental contamination worldwide. This study aimed at addressing the abundance of facemasks in an overlooked natural environment with high ecological and economic value - the wetlands (Ria de Aveiro, Portugal, as study case), evaluating their potential biodegradation using naturally occurring fungi and assessing the potential ecotoxicity of released microfibres on local bivalves. All masks collected within 6500 m2 area of Aveiro wetland were 100 % disposable ones (PP-based, confirmed by Fourier transform infrared spectroscopy - FTIR) with an initial abundance of 0.0023 items/m2 in Sept. 2021, which was reduced by ∼40 % in Apr. 2022 and ∼87 % in Sept. 2022, as a reflection of the government policies. Analysis of the carbonyl index (0.03 to 1.79) underlined their state of degradation, primarily due to sun exposure during low tides. In laboratory conditions, 1 mm2 microplastics obtained from new disposable facemasks were prone to biodegradation by Penicillium brevicompactum and Zalerion maritimum inferred from microplastics mass loss (∼22 to -26 % and ∼40 to 50 %, respectively) and FTIR spectra (particularly in the hydroxyl and carbonyl groups). In addition, microfibres released from facemasks induced sublethal effects on the clam, Venerupis corrugata, mostly in their UV-aged form when compared to pristine ones, characterised by a decrease in cellular energy allocation (CEA) and an increase in aerobic energy metabolism (ETS). Concomitantly, clams exposed to 1250 items/L of UV-aged microplastics (similar to field-reported concentrations) expressed greater clearance capacity, indicating a need to compensate for the potential energy unbalance. This study provides the first baseline monitoring of facemasks in wetlands while bringing new evidence on their biodegradation and ecotoxicity, considering environmentally relevant conditions and keystone organisms in such environments. Such studies require scientific attention for rapid regulatory action against this emerging and persistent pollutant, also targeting remediation and mitigation strategies considering these items under pandemic scenarios.


Assuntos
Poluentes Químicos da Água , Áreas Alagadas , Plásticos/análise , Microplásticos , Máscaras , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Biodegradação Ambiental
4.
Microbiol Resour Announc ; 12(4): e0001723, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36880778

RESUMO

Zalerion maritima is a marine fungus that has been studied for the biodegradation of (micro)plastics. Here, we report the draft genome sequence of strain ATCC 34329, which was shown to have a size of 58.4 Mb, a GC content of 44.39%, and 10,802 predicted genes.

5.
Polymers (Basel) ; 14(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36146011

RESUMO

Poly(2,5-furandicarboxylate)s incorporating aliphatic moieties represent a promising family of polyesters, typically entirely based on renewable resources and with tailored properties, notably degradability. This study aims to go beyond by developing poly(isosorbide 2,5-furandicarboxylate-co-dodecanedioate) copolyesters derived from isosorbide (Is), 2,5-furandicarboxylic acid (FDCA), and 1,12-dodecanedioic acid (DDA), and studying their degradation under environmental conditions, often overlooked, namely seawater conditions. These novel polyesters have been characterized in-depth using ATR-FTIR, 1H, and 13C NMR and XRD spectroscopies and thermal analysis (TGA and DSC). They showed enhanced thermal stability (up to 330 °C), and the glass transition temperature increased with the content of FDCA from ca. 9 to 60 °C. Regarding their (bio)degradation, the enzymatic conditions lead to the highest weight loss compared to simulated seawater conditions, with values matching 27% vs. 3% weight loss after 63 days of incubation, respectively. Copolymerization of biobased FDCA, Is, and DDA represents an optimal approach for shaping the thermal/(bio)degradation behaviors of these novel polyesters.

6.
Sci Total Environ ; 828: 154269, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35276171

RESUMO

Biobased and biodegradable plastic mulch films (aka, mulch biofilm) have emerged as a sustainable alternative to conventional plastic mulch films in agriculture, promising to reduce soil contamination with plastic residues through in situ biodegradation. However, current standards certifying biodegradable plastics cannot predict biodegradability in natural settings. The scarce studies considering the possible biodegradation and ecotoxicity of mulch biofilms in soil systems question the environmental friendliness of these alternative options. This study assessed the biodegradation of a commercially available mulch biofilm by the soil-dwelling fungus Penicillium brevicompactum (in solid culture media and soil for 15 and 28 days, respectively), and the ecotoxicological effects of mulch biofilm microplastics on the earthworm Eisenia andrei (pristine or UV-weathered, at 0.125-0.250-0.500 g/kg). Results (from microplastics' mass loss, microscopy, and FTIR spectroscopy) suggest that the presence of P. brevicompactum promotes mulch biofilm's biodegradation. Exposure to environmental concentrations of pristine biofilm microplastics (and its ingestion) increased earthworms' sensitivity to touch, induced physiological alterations, decreased energy reserves, and decreased their reproduction (>30%). Conversely, exposure to weathered biofilm microplastics slightly increased earthworms' sensitivity, as well as carbohydrate reserves,without affecting their reproduction. The tested mulch biofilm seems to be, at first sight, an environmentally friendly alternative as it presented susceptibility for biodegradation by a widespread fungus, and the absence of ecotoxicological chronic effects on a key macroinvertebrate species in soil ecosystems when considering environmental relevant concentrations and plastics weathered conditions. Notwithstanding, the obtained results highlight the need to revise current standards, as they often neglect the role of, and their chronic effects on, naturally occurring organisms.


Assuntos
Plásticos Biodegradáveis , Oligoquetos , Poluentes do Solo , Agricultura , Animais , Biofilmes , Ecossistema , Fungos , Microplásticos , Plásticos , Solo , Poluentes do Solo/toxicidade
7.
Molecules ; 27(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35164406

RESUMO

Sesquiterpene lactones (SL), characterized by their high prevalence in the Asteraceae family, are one of the major groups of secondary metabolites found in plants. Researchers from distinct research fields, including pharmacology, medicine, and agriculture, are interested in their biological potential. With new SL discovered in the last years, new biological activities have been tested, different action mechanisms (synergistic and/or antagonistic effects), as well as molecular structure-activity relationships described. The review identifies the main sesquiterpene lactones with interconnections between immune responses and anti-inflammatory actions, within different cellular models as well in in vivo studies. Bioaccessibility and bioavailability, as well as molecular structure-activity relationships are addressed. Additionally, plant metabolic engineering, and the impact of sesquiterpene lactone extraction methodologies are presented, with the perspective of biological activity enhancement. Sesquiterpene lactones derivatives are also addressed. This review summarizes the current knowledge regarding the therapeutic potential of sesquiterpene lactones within immune and inflammatory activities, highlighting trends and opportunities for their pharmaceutical/clinical use.


Assuntos
Anti-Inflamatórios/farmacologia , Agentes de Imunomodulação/farmacologia , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Asteraceae/química , Descoberta de Drogas , Humanos , Agentes de Imunomodulação/química , Agentes de Imunomodulação/isolamento & purificação , Lactonas/química , Lactonas/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
8.
Genes (Basel) ; 12(10)2021 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-34680970

RESUMO

HOXB7 is often overexpressed in breast cancer cells and found to relate to poor prognosis. The search for the HOXB7 targets, as a transcription factor, has led to molecules involved in regulating cell proliferation, migration, invasion, and processes such as angiogenesis and therapy resistance. However, the specific targets affected by the deregulation of HOXB7 in breast cancer remain largely unknown in most molecular sub-types, such as triple-negative breast cancers (TNBC). To unveil the molecular basis behind these aggressive and often untreatable cancers, here we explored the contribution of HOXB7 deregulation for their aggressiveness. To this end, HOXB7 was silenced in TNBC Basal A cells MDA-MB-468, and the phenotype, gene/protein expression, and methylation profile of putative targets were analyzed. Lower migration and invasion rates were detected in HOXB7-silenced cells in comparison with the controls. In addition, these cells expressed more CDH1 and less DNMT3B, and the promoter methylation status of CDH1 diminished. Our data suggest that the HOXB7 transcription factor may act on TNBC Basal A cells by controlling CDH1 epigenetic regulation. This may occur indirectly through the up-regulation of DNMT3B, which then controls DNA methylation of the CDH1 promoter. Thus, future approaches interfering with HOXB7 regulation may be promising therapeutic strategies in TNBC treatment.


Assuntos
Antígenos CD/genética , Caderinas/genética , DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Homeodomínio/genética , Neoplasias de Mama Triplo Negativas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Metilação de DNA/genética , Epigênese Genética/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Inativação Gênica , Humanos , Regiões Promotoras Genéticas/genética , Neoplasias de Mama Triplo Negativas/patologia , DNA Metiltransferase 3B
9.
Artigo em Inglês | MEDLINE | ID: mdl-34360022

RESUMO

Environmental sustainability is driving an intense search for "green materials". Biobased plastics have emerged as a promising alternative. Their building blocks can now be obtained from diverse biomass, by-products, and organic residues due to the advances in biorefineries and bioprocessing technologies, decreasing the demand for fossil fuel resources and carbon footprint. Novel biobased polymers with high added value and improved properties and functionalities have been developed to apply diverse economic sectors. However, the real opportunities and risks of such novel biobased plastic solutions have raised scientific and public awareness. This paper provides a critical review on the recent advances in biobased polymers chemistry and emerging (bio)technologies that underpin their production and discusses the potential for biodegradation, recycling, environmental safety, and toxicity of these biobased solutions.


Assuntos
Plásticos , Reciclagem , Biodegradação Ambiental , Biomassa , Polímeros
10.
Sci Rep ; 11(1): 7165, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785799

RESUMO

The overexpression of hoxd13a during zebrafish fin development causes distal endochondral expansion and simultaneous reduction of the finfold, mimicking the major events thought to have happened during the fin-to-limb transition in Vertebrates. We investigated the effect of hoxd13a overexpression on putative downstream targets and found it to cause downregulation of proximal fin identity markers (meis1 and emx2) and upregulation of genes involved in skeletogenesis/patterning (fbn1, dacha) and AER/Finfold maintenance (bmps). We then show that bmp2b overexpression leads to finfold reduction, recapitulating the phenotype observed in hoxd13a-overexpressing fins. In addition, we show that during the development of the long finfold in leot1/lofdt1 mutants, hoxd13a and bmp2b are downregulated. Our results suggest that modulation of the transcription factor Hoxd13 during evolution may have been involved in finfold reduction through regulation of the Bmp signalling that then activated apoptotic mechanisms impairing finfold elongation.


Assuntos
Nadadeiras de Animais/embriologia , Proteína Morfogenética Óssea 2/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Apoptose/genética , Padronização Corporal , Regulação para Baixo , Embrião não Mamífero , Proteínas de Homeodomínio/metabolismo , Modelos Animais , Modelos Biológicos , Mutação , Transdução de Sinais/genética , Esqueleto/embriologia , Fatores de Transcrição/metabolismo , Regulação para Cima , Peixe-Zebra
12.
Plants (Basel) ; 9(12)2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255180

RESUMO

Manganese (Mn) toxicity is a very common soil stress around the world, which is responsible for low soil fertility. This manuscript evaluates the effect of the endophytic bacterium Pseudomonas sp. Q1 on different rhizobial-legume symbioses in the absence and presence of Mn toxicity. Three legume species, Cicer arietinum (chickpea), Trifolium subterraneum (subterranean clover), and Medicago polymorpha (burr medic) were used. To evaluate the role of 1-aminocyclopropane-1-carboxylate (ACC) deaminase produced by strain Q1 in these interactions, an ACC deaminase knockout mutant of this strain was constructed and used in those trials. The Q1 strain only promoted the symbiotic performance of Rhizobium leguminosarum bv. trifolii ATCC 14480T and Ensifer meliloti ATCC 9930T, leading to an increase of the growth of their hosts in both conditions. Notably, the acdS gene disruption of strain Q1 abolished the beneficial effect of this bacterium as well as causing this mutant strain to act deleteriously in those specific symbioses. This study suggests that the addition of non-rhizobia with functional ACC deaminase may be a strategy to improve the pasture legume-rhizobial symbioses, particularly when the use of rhizobial strains alone does not yield the expected results due to their difficulty in competing with native strains or in adapting to inhibitory soil conditions.

13.
Cancers (Basel) ; 13(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375038

RESUMO

Invasion and metastasis correspond to the foremost cause of cancer-related death, and the molecular networks behind these two processes are extremely complex and dependent on the intra- and extracellular conditions along with the prime of the premetastatic niche. Currently, several studies suggest an association between the levels of HOX genes expression and cancer cell invasion and metastasis, which favour the formation of novel tumour masses. The deregulation of HOX genes by HMGA2/TET1 signalling and the regulatory effect of noncoding RNAs generated by the HOX loci can also promote invasion and metastasis, interfering with the expression of HOX genes or other genes relevant to these processes. In this review, we present five molecular mechanisms of HOX deregulation by which the HOX clusters products may affect invasion and metastatic processes in solid tumours.

14.
Cells ; 9(7)2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635388

RESUMO

HOX genes are commonly known for their role in embryonic development, defining the positional identity of most structures along the anterior-posterior axis. In postembryonic life, HOX gene aberrant expression can affect several processes involved in tumorigenesis such as proliferation, apoptosis, migration and invasion. Epigenetic modifications are implicated in gene expression deregulation, and it is accepted that methylation events affecting HOX gene expression play crucial roles in tumorigenesis. In fact, specific methylation profiles in the HOX gene sequence or in HOX-associated histones are recognized as potential biomarkers in several cancers, helping in the prediction of disease outcomes and adding information for decisions regarding the patient's treatment. The methylation of some HOX genes can be associated with chemotherapy resistance, and its identification may suggest the use of other treatment options. The use of epigenetic drugs affecting generalized or specific DNA methylation profiles, an approach that now deserves much attention, seems likely to be a promising weapon in cancer therapy in the near future. In this review, we summarize these topics, focusing particularly on how the regulation of epigenetic processes may be used in cancer therapy.


Assuntos
Metilação de DNA , Código das Histonas , Proteínas de Homeodomínio/genética , Neoplasias/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Proteínas de Homeodomínio/metabolismo , Humanos , Metiltransferases/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
15.
Food Chem ; 331: 127323, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32554310

RESUMO

Beverages, often packaged in plastic, can be a source of microplastics in the human diet. In this study, an improved method for detection of microplastics in white wines capped with synthetic stoppers is explored. Visual quantification in the stereomicroscope or using Nile Red were excluded due to the small size of particles. Quantification in the optical microscope identified up to 5,857 particles.L-1 but lacked chemical characterization. Finally, micro-Raman spectroscopy was used for the first time in complex beverages in the identification of microplastics particles in white wines, allowing identification of at least one synthetic particle for each bottle, except in two cases. Improvements included reduction in volume filtered, selection of aluminum oxide filters, selection of blue laser and lack of H2O2 treatment. Using this method, identification of all particles present in small representative areas of the filter by micro-Raman spectroscopy will allow proper quantification of microplastics in complex beverage matrices.


Assuntos
Microplásticos/análise , Microplásticos/química , Polietileno/química , Análise Espectral Raman , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Vinho/análise , Monitoramento Ambiental , Humanos , Peróxido de Hidrogênio/química , Oxazinas/química
16.
Life (Basel) ; 10(3)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178383

RESUMO

The overgrowth of human population and the demand for high-quality foods necessitate the search for sustainable alternatives to increase crop production. The use of biofertilizers, mostly based on plant probiotic bacteria (PPB), represents a reliable and eco-friendly solution. This heterogeneous group of bacteria possesses many features with positive effects on plants; however, how these bacteria with each other and with the environment when released into a field has still barely been studied. In this review, we focused on the diversity of root endophytic rhizobial and non-rhizobial bacteria existing within plant root tissues, and also on their potential applications as consortia exerting benefits for plants and the environment. We demonstrated the benefits of using bacterial inoculant consortia instead of single-strain inoculants. We then critically discussed several considerations that farmers, companies, governments, and the scientific community should take into account when a biofertilizer based on those PPBs is proposed, including (i) a proper taxonomic identification, (ii) the characterization of the beneficial features of PPB strains, and (iii) the ecological impacts on plants, environment, and plant/soil microbiomes. Overall, the success of a PPB consortium depends on many factors that must be considered and analyzed before its application as a biofertilizer in an agricultural system.

17.
Sci Total Environ ; 709: 135892, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31884269

RESUMO

Coastal environments are highly contaminated with plastics of various sizes. In order to understand the distribution and factors influencing (micro)plastics contamination in the environment, sampling of a sandy beach in Costa Nova, Aveiro, Portugal, was conducted by collecting plastic particles and sediments for density separation in transects from the mean low tide line to the dunes, during wet and dry seasons. For surface collection, microplastics comprised 69.4% of plastics, presenting concentrations of 3-6 items m-2 in the wet season, mostly polyethylene pellets carried ashore by storms, and <1 item m-2 for dry season, lower due to less backwashing, were found. Collection of infrared spectra of these particles allowed characterization by polymer type and carbonyl index of all particles. Variations in carbonyl index were found to be related to season, site and particle color. Density separated microplastics, mostly fibers, presented 23 times higher concentrations than surface collection (22 microplastics kg-1, 280 microplastics m-2), due to the identification of smaller sizes, and with higher concentrations in dry seasons, likely from accumulation in sediment and bathing season. Overall, different sampling methods allowed identification of different particle types and sizes, which may vary according to seasonal and spatial factors.

18.
Genes (Basel) ; 10(12)2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817529

RESUMO

Eukaryotic genomes are rich in repetitive DNA sequences grouped in two classes regarding their genomic organization: tandem repeats and dispersed repeats. In tandem repeats, copies of a short DNA sequence are positioned one after another within the genome, while in dispersed repeats, these copies are randomly distributed. In this review we provide evidence that both tandem and dispersed repeats can have a similar organization, which leads us to suggest an update to their classification based on the sequence features, concretely regarding the presence or absence of retrotransposons/transposon specific domains. In addition, we analyze several studies that show that a repetitive element can be remodeled into repetitive non-coding or coding sequences, suggesting (1) an evolutionary relationship among DNA sequences, and (2) that the evolution of the genomes involved frequent repetitive sequence reshuffling, a process that we have designated as a "DNA remodeling mechanism". The alternative classification of the repetitive DNA sequences here proposed will provide a novel theoretical framework that recognizes the importance of DNA remodeling for the evolution and plasticity of eukaryotic genomes.


Assuntos
Eucariotos/genética , Evolução Molecular , Retroelementos/fisiologia , Sequências de Repetição em Tandem/fisiologia
19.
Microorganisms ; 7(10)2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557944

RESUMO

Bacterial endophytes, a subset of a plant's microbiota, can facilitate plant growth by a number of different mechanisms. The aims of this study were to assess the diversity and functionality of endophytic bacterial strains from internal root tissues of native legume species grown in two distinct sites in South of Portugal and to evaluate their ability to promote plant growth. Here, 122 endophytic bacterial isolates were obtained from 12 different native legume species. Most of these bacteria possess at least one of the plant growth-promoting features tested in vitro, with indole acetic acid production being the most common feature among the isolates followed by the production of siderophores and inorganic phosphate solubilization. The results of in planta experiments revealed that co-inoculation of chickpea plants with specific endophytic bacteria along with N2-fixing symbionts significantly improved the total biomass of chickpea plants, in particular when these plants were grown under saline conditions. Altogether, this study revealed that Mediterranean native legume species are a reservoir of plant growth-promoting bacteria, that are also tolerant to salinity and to toxic levels of Mn. Thus, these bacterial endophytes are well adapted to common constraints present in soils of this region which constitutes important factors to consider in the development of bacterial inoculants for stressful conditions in the Mediterranean region.

20.
Epigenomics ; 11(13): 1539-1552, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31556724

RESUMO

Several HOX genes are aberrantly expressed in a wide range of cancers interfering with their development and resistance to treatment. This seems to be often caused by alterations in the methylation profiles of their promoters. The role of HOX gene products in cancer is highly 'tissue specific', relying ultimately on their ability to regulate oncogenes or tumor-suppressor genes, directly as transcriptional regulators or indirectly interfering with the levels of epigenetic regulators. Nowadays, different strategies have been tested the use of HOX genes as therapeutic targets for cancer diagnosis and treatment. Here, we trace the history of the research concerning the involvement of HOX genes in cancer, their connection with epigenetic regulation and their potential use as therapeutic targets.


Assuntos
Transformação Celular Neoplásica/genética , Metilação de DNA , Proteínas de Homeodomínio/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Transformação Celular Neoplásica/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos
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