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1.
Int Orthop ; 46(12): 2785-2791, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35945465

RESUMEN

BACKGROUND: The most frequent indication for total hip arthroplasty (THA) in adolescent patients has been juvenile idiopathic arthritis (JIA). However, in recent years, other causes have become more prevalent. QUESTIONS/PURPOSES: (1) What is the survivorship following THA across the diagnostic spectrum in adolescent population? (2) How are quality of life results affected by systemic medical conditions? METHODS: We retrospectively reviewed all consecutive THA in patients under 21 years of age, performed at our Institution between 1993 and 2018. There were 34 prostheses implanted in 26 patients with a mean age of 18.4 years (range 11 to 21). The most frequent diagnosis was JIA (14 hips), followed by avascular necrosis (10 hips). Patient reported outcomes were assessed using Harris and Oxford Hip Scores (HHS and OHS), Visual Analogue Scale (VAS) and EuroQol-5D. Survivorship for revision and aseptic loosening was determined with Kaplan Meier analysis. RESULTS: At final follow-up, the overall survival rate was of 89.3% at 12-year follow-up. Three acetabular components underwent revision surgery for aseptic loosening. Clinical HHS significantly improved from 37.5 to 90.6 points (p < 0.001). Mean OHH was 37.4 points, with a final VAS of 1.64 points. Mean 5Q-5D was 0.704 with an interquartile range of 0.4 to 1.0. JIA patients displayed worse pre-operative HHS scores, and at final follow-up had worse HHS, OHS, VAS and EQ-5D scores compared to the rest of the patients. Complications included three intra-operative femoral fractures, one sciatic nerve palsy and one adductor contracture. CONCLUSION: THA in adolescent patients provides improved functional outcomes with acceptable revision rates at mid-term follow-up.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Supervivencia , Humanos , Adolescente , Niño , Adulto Joven , Adulto , Artroplastia de Reemplazo de Cadera/efectos adversos , Calidad de Vida , Estudios Retrospectivos , Medición de Resultados Informados por el Paciente
2.
Environ Monit Assess ; 191(3): 156, 2019 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-30747380

RESUMEN

Traffic-related metal emissions have become a global concern due to their deposition in roadside soils and potential hazardous effects. This study evaluates metal levels in soils adjoining four highways of Rio de Janeiro (Linha Vermelha, Via Dutra, BR-465, and Avenida Brasil), chosen for their diverse traffic volumes, age, and urban/rural settings. In addition to soil physicochemical properties, 11 elements (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V, and Zn) were assessed on samples collected at different distances from the road (1, 3, 5, 10, 15 m) and soil depths (0-15 and 15-30 cm). Moreover, the geoaccumulation index was also computed to infer the soil contamination extent. The results indicate that soil metal levels at each highway are highly dependent on factors like traffic volume, distance to road, other anthropogenic sources of pollution, and their rural or urban location. The highways with greater traffic volume, Linha Vermelha and Avenida Brasil (154,000 and 126,000 vehicles day-1, respectively), clearly presented the highest soil metal concentrations. Still, as stressed by the principal component analysis, traffic volume alone fails to explain the distribution of metals in soils neighboring these highways. Thus, factors like their urban setting and larger exposure to anthropogenic activities may play a pivotal role. On the other hand, soils from Via Dutra and BR-465, both on a rural backdrop, were mostly influenced by traffic as their metal levels decreased with increasing distances from the road. Comparison with reference and preventive values for Brazilian soils and the assessment of the geoaccumulation index have shown that concentrations of Pb and V have reached concerning thresholds at Linha Vermelha and Avenida Brasil.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Brasil , Contaminación Ambiental/análisis , Suelo/química , Transportes/estadística & datos numéricos , Urbanización , Emisiones de Vehículos/análisis
3.
Mol Pharm ; 12(1): 150-61, 2015 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-25384057

RESUMEN

The applicability of small interfering RNA (siRNA) in future therapies depends on the availability of safe and efficient carrier systems. Ideally, siRNA delivery requires a system that is stable in the circulation but upon specific uptake into target cells can rapidly release its cargo into the cytoplasm. Previously, we evaluated a novel generation of carrier systems ("decationized" polyplexes) for DNA delivery, and it was shown that folate targeted decationized polyplexes had an excellent safety profile and showed intracellular triggered release upon cell specific uptake. Targeted decationized polyplexes consist of a core of disulfide cross-linked poly(hydroxypropyl methacrylamide) (pHPMA) stably entrapping nucleic acids and a shell of poly(ethylene glycol) (PEG) decorated with folate molecules. In the present study, the applicability of folate targeted decationized polyplexes for siRNA delivery was investigated. This required optimization of the carrier system particularly regarding the cross-linking density of the core of the polyplexes. Stable and nanosized siRNA decationized polyplexes were successfully prepared by optimizing the cross-link density of their core. Upon incubation in human plasma, a significant portion of siRNA remained entrapped in the decationized polyplexes as determined by fluorescence correlation spectroscopy (FCS). When tested in a folate receptor overexpressing cell line stably expressing luciferase, Skov3-luc, sequence specific gene silencing was observed. As expected, neither interference on the intrinsic luciferase expression nor on the cell metabolic activity (determined by XTT) was induced by the free-polymer or the siRNA polyplexes. In conclusion, targeted decationized polyplexes are safe and stable carriers that interact with the targeted cells and rapidly disassemble upon cell entry making them promising siRNA delivery systems.


Asunto(s)
Técnicas de Transferencia de Gen , Metacrilatos/química , Nanopartículas/química , ARN Interferente Pequeño/administración & dosificación , Materiales Biocompatibles/química , Línea Celular Tumoral , Ácido Fólico/química , Silenciador del Gen , Humanos , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión , Nanotecnología , Ácidos Nucleicos/química , Polietilenglicoles/química , Polímeros/química , Espectrofotometría Ultravioleta
4.
Bioconjug Chem ; 25(4): 802-12, 2014 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-24650304

RESUMEN

Decationized polyplexes have previously shown unique features, especially regarding their excellent cytocompatibility and very low degree of nonspecific cellular uptake. In the present study, targeted disulfide cross-linked decationized polyplexes were composed of a core of disulfide cross-linked poly(hydroxypropyl methacrylamide) (pHPMA) stably entrapping plasmid DNA (pDNA) and a shell of poly(ethylene glycol) (PEG) decorated with folate molecules. Folate was used as targeting ligand because of its high binding affinity to its receptor, which is overexpressed in many tumors. Studies using folate receptor overexpressing cell lines (HeLa and OVCAR-3) showed significantly higher cell uptake for the folate-targeted decationized polyplexes, when compared to their nontargeted counterparts. On the contrary, for a nonexpressing folate receptor cell line (A549) similar uptake was observed for both targeted and nontargeted decationized polyplexes. Transfection studies using OVCAR-3 cells showed higher transfection efficiency for folate-targeted polyplexes, because of improved cellular uptake. Simultaneously, introduction of targeting moiety on polyplexes did not affect their good cytocompatibilty. The results reported in this paper demonstrate that coupling of folate to decationized polyplexes generates a potential system for targeted gene delivery.


Asunto(s)
Acrilamidas/química , Sistemas de Liberación de Medicamentos/métodos , Ácido Fólico/metabolismo , Plásmidos/metabolismo , Polietilenglicoles/química , Transfección/métodos , Acrilamidas/metabolismo , Disulfuros/química , Ácido Fólico/química , Transportadores de Ácido Fólico/genética , Transportadores de Ácido Fólico/metabolismo , Células HeLa , Humanos , Estructura Molecular , Polietilenglicoles/metabolismo , Células Tumorales Cultivadas
5.
J Pharm Pharm Sci ; 17(4): 461-74, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25579429

RESUMEN

PURPOSE: The aim of this study was to investigate the in vitro gene delivery efficiency of poly[N-(2-aminoethyl)ethylene-imine](PAEEI), a polymer with a linear Polyethyleneimine (LPEI) backbone and with aminoethyl side groups that has two protonatable nitrogen atoms per monomer unit instead of one as in LPEI (an established gene delivery polymer). Method. PAEEI (Mn=4.5 kDa, Mw= 10 kDa) was synthesized by ring-opening polymerization of N-(2-(1'-aziridino)ethyl)formamide followed by hydrolysis of the amide groups. The buffering capacity of the resulting polymer was determined by acid-base titration and consequently the percentage of the protonated nitrogen atoms was calculated. Polyplexes were prepared separately in buffers with different ionic strength including Hepes buffered saline (150 mM NaCl) and Hepes buffered glucose (5% glucose) and their zeta-potential, hydrodynamic diameter and colloidal stability were measured. Transfection activity (and toxicity in Hela cells) of the polyplexes were done in HeLa, CHO and HEK293T cells. Cell incubations with polyplexes were done both in the presence and absence (HeLa cells) of serum. Results. PAEEEI showed two times more buffering capacity than LPEI. PAEEI-based Polyplexes had about the same size and zeta-potential as those of LPEI, with a higher colloidal stability in saline buffer in continuous particle size measurement. Their transfection activity was slightly higher than 22-kDa LPEI polyplexes whereas their toxicity profiles were similar in cell lines studied. The PAEEI polyplexes showed gene expression activity both in the presence and absence of serum. Conclusion. Paying attention to the fact that LPEI molecules with smaller sizes than 22 kDa show less transfection efficiency than LPEI 22, the effect of smaller size of PAEEI (10 kDa) on the gene delivery efficiency was compensated by its higher buffering capacity due to carrying more protonatable nitrogen per monomeric unit comparing with LPEI (22 kDa). Having slightly higher transfection efficiency and better colloidal stability than PEI-based systems, PAEEI is an attractive candidate for future in vivo gene delivery studies.


Asunto(s)
Técnicas de Transferencia de Gen , Polietileneimina/química , Polímeros/química , Transfección , Animales , Células CHO , Cricetinae , Cricetulus , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Células HeLa , Humanos , Nitrógeno/química , Tamaño de la Partícula , Polietileneimina/toxicidad , Polímeros/toxicidad
6.
ScientificWorldJournal ; 2014: 506392, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25386602

RESUMEN

Mine tailings represent a serious threat to the environment and human health; thus their restoration has become a major concern. In this study, the interactions between Brassica juncea and different mine soil treatments were evaluated in order to understand their effect on germination and early growth. Three soil treatments containing 25% and 50% of technosol and 30% of compost were prepared. Germination and early growth were assessed in soil and pore water extracts from the treatments. Unlike the untreated mine soil, the three treatments allowed germination and growth, achieving levels comparable to those of seedlings from the same species developed in normal conditions. The seedlings grown in 50% of technosol and 30% of compost exhibited greater germination percentages, higher growth, and more efficient mechanisms against oxidative stress, ascribed to the organic matter and nutrients content of these treatments. Considering the unequivocal ability of B. juncea for phytoremediation, the results suggest that technosol and compost may be an auspicious solution to allow the germination and early growth of this species in mine tailings.


Asunto(s)
Germinación/efectos de los fármacos , Planta de la Mostaza/crecimiento & desarrollo , Suelo/química , Cobre/toxicidad , Minería , Planta de la Mostaza/efectos de los fármacos , Plantones/efectos de los fármacos , Zinc/química
7.
Biomacromolecules ; 14(6): 1826-37, 2013 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-23607866

RESUMEN

Thermosensitive amphiphilic block copolymers self-assemble into micelles above their lower critical solution temperature in water, however, the micelles generally display mediocre physical stability. To stabilize such micelles and increase their loading capacity for chemotherapeutic drugs, block copolymers with novel aromatic monomers were synthesized by free radical polymerization of N-(2-benzoyloxypropyl methacrylamide (HPMAm-Bz) or the corresponding naphthoyl analogue (HPMAm-Nt), with N-(2-hydroxypropyl) methacrylamide monolactate, using a polyethylene glycol based macroinitiator. The critical micelle temperatures and critical micelle concentrations decreased with increasing the HPMAm-Bz/Nt content. The micelles of 30-50 nm were prepared by heating the polymer aqueous solutions from 0 to 50 °C and were colloidally stable for at least 48 h at pH 7.4 and 37 °C. Paclitaxel and docetaxel encapsulation was performed by mixing drug solutions in ethanol with polymer aqueous solutions and heating from 0 to 50 °C. The micelles had a drug loading capacity up to 34 wt % for docetaxel, which is among the highest loadings reported for polymeric micelles, with loaded micelle sizes ranging from 60 to 80 nm. The micelles without aromatic groups almost completely released loaded paclitaxel in 10 days, whereas the HPMAm-Bz/Nt containing micelles released 50% of the paclitaxel at the same time, which showed a better retention for the drug of the latter micelles. (1)H solid-state NMR spectroscopy data are compatible with π-π stacking between aromatic groups. The empty micelles demonstrated good cytocompatibility, and paclitaxel-loaded micelles showed high cytotoxicity to tumor cells. In conclusion, the π-π stacking effect introduced by aromatic groups increases the stability and loading capacity of polymeric micelles.


Asunto(s)
Antineoplásicos/química , Micelas , Polímeros/química , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión , Temperatura
8.
Chemosphere ; 314: 137688, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36584825

RESUMEN

Bioremediation of mining soils using metal tolerant fungi is widely considered as a promising cost-effective and ecofriendly approach. This study assessed the copper removal efficiency and bioaccumulation ability of the indigenous species Aspergillus hiratsukae LF1 and Aspergillus terreus LF2 isolated from the soils of an abandoned copper mine in Oman. Nutrient medium containing five different Cu (II) levels (0 - control, 100, 200, 300 and 500 mg/L) was employed for assessing both parameters. The removal efficiency from nutrient medium (100-500 mg Cu per L) ranged from 57% to 21% for A. hiratsukae LF1, and from 69% to 24% for A. terreus LF2. A. hiratsukae LF1 and A. terreus LF2 accumulated a maximum of 4.63 and 5.95 mg Cu/g,espectively, at 500 mg/L of Cu (II) concentration. The compositional analysis of extracellular polymeric substances excreted by both species revealed a hormetic response by A. hiratsukae LF1 at 100 mg/L; whereas increasing media Cu levels induced carbohydrates production in A. terreus LF2. These results hint at the involvement of carbohydrates in the Cu-tolerance mechanism of the latter. Copper accumulation in both species was further demonstrated through scanning electron microscopy and energy dispersive spectrometry. In line with the pertaining literature, our results are somewhat inconclusive concerning whether proteins or carbohydrates play a more pivotal role in copper complexation in both species; yet, FTIR analysis showed the participation of different functional groups in Cu sorption. Overall, although additional research is required to advance the knowledge about both Aspergillus species, our findings suggest that A. terreus LF2 presents greater promise for copper bioremediation due to enhanced tolerance and accumulation capacity.


Asunto(s)
Cobre , Contaminantes del Suelo , Cobre/análisis , Biodegradación Ambiental , Suelo/química , Hongos/metabolismo , Aspergillus/metabolismo , Contaminantes del Suelo/análisis
9.
Environ Sci Pollut Res Int ; 30(8): 22089-22099, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36282385

RESUMEN

In this exploratory study, naturally occurring Salvinia biloba Raddi specimens were assessed for atrazine and carbendazim polluted water remediation. Experiments were carried out over 21 days in glass vessels containing deionized water artificially contaminated with 0, 5, 10, and 20 mg L-1 of atrazine or carbendazim. Atrazine had a pronounced detrimental impact on S. biloba, as no biomass development was observed in all macrophytes exposed to this herbicide in the entire concentration range. However, carbendazim-treated plants were able to grow and survive in the polluted medium even when subjected to the highest concentration of this fungicide (i.e., 20 mg L-1). In addition, increased chlorosis and necrosis were also detected in plants subjected to carbendazim as a result of the high phytotoxicity caused by atrazine. A maximal removal efficiency of ~ 30% was observed for both pesticides at 5 mg L-1 and decreased with increasing concentrations of the pollutants. The spectrum of the FTIR-ATR analysis revealed the existence of various functional groups (e.g., amide, carboxyl, hydroxyl, phosphate, sulfate) on the plants, which could be related to pesticide biosorption. In addition, at the end of the 21-day assay, seven carbendazim-resistant bacteria could be isolated from the roots of fungicide-treated plants. Therefore, the use of autochthonous free-floating S. biloba macrophytes for phytoremediation of aquatic environments contaminated with carbendazim shows great promise. Still, additional research is required to further elucidate the plant-mediated carbendazim elimination process and the role of the herbicide-resistant bacteria, and seek alternative species capable of mitigating atrazine contamination.


Asunto(s)
Atrazina , Fungicidas Industriales , Herbicidas , Plaguicidas , Tracheophyta , Contaminantes Químicos del Agua , Atrazina/análisis , Fungicidas Industriales/análisis , Herbicidas/análisis , Plaguicidas/análisis , Biodegradación Ambiental , Agua/análisis , Contaminantes Químicos del Agua/análisis
10.
Metabolites ; 13(10)2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37887423

RESUMEN

Due to the increased incidence of obesity, it is of great importance to identify all the possible consequences in those who suffer from it and their descendants. This study aimed to investigate how paternal obesity, resulting from an 18-week high-fat diet (HFD), affects the metabolic and reproductive health of offspring. In the fathers (F0 generation), the HFD led to significant weight gain, primarily due to increased visceral fat. It also resulted in impaired glucose control and reduced insulin sensitivity. Furthermore, F0 males from the HFD group had reduced sperm concentration and lower sperm viability but were still able to sire litters. F1 offspring were monitored during 18 weeks; F1 offspring from obese fathers displayed increased body weight during the experimental window, especially in males, without significant metabolic disturbances. Additionally, F1 males showed reduced sperm viability, indicating potential reproductive implications. On the other hand, F1 females showed normal estrous cycle patterns but had a reduced number of primordial follicles, suggesting a decrease in their follicular reserve and reproductive potential. This study highlights that metabolic and reproductive issues may be passed down to future generations through the paternal line.

11.
J Gen Virol ; 93(Pt 4): 866-875, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22190012

RESUMEN

In this study, the complete genome sequences of seven equine group A rotavirus (RVA) strains (RVA/Horse-tc/GBR/L338/1991/G13P[18], RVA/Horse-wt/IRL/03V04954/2003/G3P[12] and RVA/Horse-wt/IRL/04V2024/2004/G14P[12] from Europe; RVA/Horse-wt/ARG/E30/1993/G3P[12], RVA/Horse-wt/ARG/E403/2006/G14P[12] and RVA/Horse-wt/ARG/E4040/2008/G14P[12] from Argentina; and RVA/Horse-wt/ZAF/EqRV-SA1/2006/G14P[12] from South Africa) were determined. Multiple novel genotypes were identified and genotype numbers were assigned by the Rotavirus Classification Working Group: R9 (VP1), C9 (VP2), N9 (NSP2), T12 (NSP3), E14 (NSP4), and H7 and H11 (NSP5). The genotype constellation of L338 was unique: G13-P[18]-I6-R9-C9-M6-A6-N9-T12-E14-H11. The six remaining equine RVA strains showed a largely conserved genotype constellation: G3/G14-P[12]-I2/I6-R2-C2-M3-A10-N2-T3-E2/E12-H7, which is highly divergent from other known non-equine RVA genotype constellations. Phylogenetic analyses revealed that the sequences of these equine RVA strains are related distantly to non-equine RVA strains, and that at least three lineages exist within equine RVA strains. A small number of reassortment events were observed. Interestingly, the three RVA strains from Argentina possessed the E12 genotype, whereas the three RVA strains from Ireland and South Africa possessed the E2 genotype. The unusual E12 genotype has until now only been described in Argentina among RVA strains collected from guanaco, cattle and horses, suggesting geographical isolation of this NSP4 genotype. This conserved genetic configuration of equine RVA strains could be useful for future vaccine development or improvement of currently used equine RVA vaccines.


Asunto(s)
Secuencia Conservada/genética , Gastroenteritis/veterinaria , Genoma Viral/genética , Enfermedades de los Caballos/virología , Infecciones por Rotavirus/veterinaria , Rotavirus/genética , Animales , Secuencia de Bases , Gastroenteritis/virología , Genes Virales/genética , Genotipo , Caballos/virología , Datos de Secuencia Molecular , Filogenia , Infecciones por Rotavirus/virología
12.
Sci Total Environ ; 838(Pt 4): 156435, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35660615

RESUMEN

Soil metal contamination is a major concern due to the ever-rising number of areas afflicted worldwide and the detrimental effects of metals to the environment and human health. Due to their non-biodegradability and toxicity, it is paramount to prevent further metal contamination and remediate the thousands of contaminated sites across the planet. Yet, conventional reclamation based on physical and chemical methods is often expensive, impractical, and triggers secondary pollution issues. Hence, microbe-aided phytoremediation has been gaining significant traction due to its environment-friendly character, cost-effectiveness, and the breakthroughs achieved during the past few decades. Microorganisms are an essential part of natural ecosystems and play a crucial role in their restoration. Indeed, plant-microbe associations in metal-polluted soils are pivotal for plants to tolerate metal toxicity and thrive in these harsh environments. Therefore, improving the understanding of this intricate relationship is invaluable for boosting phytoremediation. In this review, we focus on the potential of plant growth promoting bacteria (PGPB) for enhancing phytoremediation of metal-polluted soils. We discuss the mechanisms employed by microbes to promote plant growth and assist the removal or immobilization of metals in soil, thereby enhancing phytoextraction and phytostabilization, respectively. Microbe-mediated metal removal and detoxification through processes entailing adsorption, chelation, transformation, and precipitation, to list but a few, are also critically examined. Moreover, this work covers the direct and indirect mechanisms used by PGPB to facilitate plant acquisition of nutrients like nitrogen and phosphorus, supply and regulate phytohormones, and exert control over antagonistic microorganisms. Lastly, we provide an outlook on the future directions of microbe-aided phytoremediation and phytomining. Clearly, to fully validate and comprehend the potential of PGPB-aided phytoremediation, a considerable shift from bench-scale to field research is necessary. What's more, it is envisaged that recent advancements in genetic engineering may soon help furthering the efficiency of microbe-assisted phytoremediation.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Bacterias , Biodegradación Ambiental , Ecosistema , Humanos , Plantas/microbiología , Suelo/química , Contaminantes del Suelo/análisis
13.
Chemosphere ; 303(Pt 3): 135051, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35671821

RESUMEN

Anthropogenic and natural sources influence trace metals (TMs) bound to different sized particulate matter (PM) in dry and wet atmospheric deposition, which can create ecosystem and human health issues in the long run. Limited reviews are available summarizing worldwide concentrations in TMs in atmospheric PMs, their sources and pathways. Simultaneously, quantitative assessment of the potential human and ecosystem health risks imposed by the atmospheric particulate matter has not been adequately reviewed. Addressing this gap, here we review, the concentration of TMs in dry deposition mainly varies with the responsible sources, whereas, in wet deposition, it depends on the solubility of TMs. Other than deposition on impervious surfaces, the TMs incorporated PM can be deposited on biological agents. Health risk assessments show that ingestion and dermal contact pathways are more likely to cause health issues, however, the probability of occurring ingestion and dermal contact pathways is limited. Attention must be paid to the contribution from non-exhaust and exhaust vehicular emissions for TMs in atmospheric deposition, understanding their impact on stormwater management and urban agriculture. Behaviors of TMs in the atmosphere depends on many complex factors including origin, wind patterns, and weather conditions. Therefore, future research needs to be carried to model and predict the fate and transfer of TMs once they are generated through natural and anthropogenic sources. We believe that such research would allow establishing pollution control policies and measures in urban environments which will be critical to reduce the levels of TMs associated with atmospheric deposition in the environment.


Asunto(s)
Contaminantes Atmosféricos , Metales Pesados , Oligoelementos , Contaminantes Atmosféricos/análisis , Ecosistema , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Material Particulado/análisis , Medición de Riesgo , Oligoelementos/análisis , Emisiones de Vehículos
14.
Plants (Basel) ; 10(12)2021 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-34961150

RESUMEN

Free-living macrophytes play an important role in the health of aquatic ecosystems. Therefore, the use of aquatic plants as metal biomonitors may be a suitable tool for the management of freshwater reservoirs. Hence, in this study, we assessed the effects of cadmium (Cd) in Salvinia biloba specimens collected from the Middle Paraná River during a 10-day experiment employing artificially contaminated water (100 µM Cd). S. biloba demonstrated a great ability for Cd bioaccumulation in both the root-like modified fronds (named "roots") and the aerial leaf-like fronds (named "leaves") of the plants. Additionally, Cd toxicity was determined by the quantification of photosynthetic pigments (chlorophylls a and b, and carotenoids), flavonoids, and soluble carbohydrate contents in S. biloba over time (1, 3, 5, 7, and 10 days). In general, deterioration was more pronounced in leaves than in roots, suggesting a greater implication of the former in long-term Cd sequestration in S. biloba. Deleterious effects in the appraised parameters were well correlated with the total amount of Cd accumulated in the leaves, and with the qualitative changes observed in the plants' phenotype during the 10-day metal exposure assay. The flavonoids and carotenoids in leaves were highly affected by low Cd levels followed by root carbohydrates. In contrast, chlorophylls and root flavonoids were the least impacted physiological parameters. Therefore, our results demonstrate that S. biloba displays dissimilar organ-linked physiological responses to counteract Cd phytotoxicity and that these responses are also time-dependent. Though further research is needed, our work suggests that easy-handled physiological data obtained from autochthonous free-floating S. biloba specimens may be used as a valuable tool for metal-polluted water biomonitoring.

15.
J Virol ; 83(7): 2917-29, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19153225

RESUMEN

A limited number of human G6P[14] rotavirus strains that cause gastroenteritis in humans have been isolated in Europe and Australia. The complete genome sequences were determined for five of these human strains--B10925-97 (isolated in Belgium in 1997), 111/05-27 (Italy, 2005), PA169 (Italy, 1987), MG6 (Australia, 1993), and Hun5 (Hungary, 1997)--and their genetic relatedness to animal rotavirus strains was evaluated by sequencing the complete genome of the sheep rotavirus OVR762 (G8P[14]; Spain, 2002), the guanaco (Lama guanicoe) rotavirus strains Arg/Chubut/99 and Arg/Río Negro/98 (G8P[14] and G8P[1], respectively; Argentina, 1999 and 1998), the sable antelope strain RC-18/08 (G6P[14]; South Africa, 2008), and the bovine rotavirus strain Arg/B383/98 (G15P[11]; Argentina, 1998). These analyses revealed an overall consensus genomic constellation (G6/G8)-P[14]-I2-(R2/R5)-C2-M2-(A3/A11)-N2-T6-(E2/E12)-H3, together with a few gene reassortments, and the phylogenetic analyses confirmed that the P[14] human strains evaluated in this study were closely related to rotavirus strains isolated from sheep, cattle, goats, guanacos, and antelopes and to rabbits (albeit to a lesser extent), suggesting that one (or more) of these animal species might be the source of the human G6P[14] strains. The main feature of the genotype and phylogenetic analyses was the close overall genomic relatedness between the five human G6P[14] rotavirus strains and the ovine and antelope rotavirus strains. Taken together, these data strongly suggest a common origin for the human P[14] strains and those of the even-toed ungulates belonging to the mammalian order Artiodactyla, with sheep probably playing a key role in the interspecies transmission responsible for the introduction of P[14] rotavirus strains into the human population.


Asunto(s)
Gastroenteritis/virología , ARN Viral/genética , Infecciones por Rotavirus/virología , Rotavirus/genética , Rotavirus/aislamiento & purificación , Australia , Preescolar , Europa (Continente) , Evolución Molecular , Humanos , Lactante , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia
16.
Virus Res ; 137(1): 157-62, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18674575

RESUMEN

Although G9 rotaviruses have become one of the important rotavirus genotypes worldwide, they have been uncommon in China. Recently, we reported G9 rotaviruses as a highly prevalent genotype in Xinjiang, the northwest part of China [Yang, X., Matthijnssens, J., Sun, H., Muhamaiti, J., Zhang, B., Nahar, S., Van Ranst, M., Rahman, M., 2008. Temporal changes of rotavirus strain distribution in a northwest city of China, 1996-2005. Int. J. Infect. Dis., June (Epub ahead of print)]. Here we report the genetic variations of the Xinjiang-G9 rotaviruses isolated between 1999 and 2005. Sequence analysis of the VP7 genes of Xinjiang-G9 strains indicated that they were more closely related to the contemporary global G9 strains than to the prototype Chinese G9 strains. However, their VP4 genes were most similar to those from the locally circulating G1P[8], G2P[4], G3P[6] and G3P[8] strains. This indicates that reassortment rather than antigenic drift might be the preferred evolutionary mechanism for the emergence of the G9 rotaviruses in Xinjiang. These findings will be of major significance for understanding the emergence of newly introduced rotavirus strains.


Asunto(s)
Enfermedades Transmisibles Emergentes/virología , Infecciones por Rotavirus/virología , Rotavirus/clasificación , Rotavirus/genética , Antígenos Virales/genética , Proteínas de la Cápside/genética , China , Heces/virología , Variación Genética/genética , Genotipo , Datos de Secuencia Molecular , Filogenia , Rotavirus/aislamiento & purificación , Especificidad de la Especie
17.
Plants (Basel) ; 7(3)2018 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-30720787

RESUMEN

The arrival of sequence-specific endonucleases that allow genome editing has shaken the pillars of basic and applied plant biology. Clustered regularly interspaced palindromic repeats (CRISPR) is a revolutionary genome-engineering tool that enables the enhancement of targeted traits in plants. Numerous plants, including energy crops, known for their potential to tolerate, immobilize, and stabilize inorganic and organic pollutants, have already been edited using different CRISPR systems. Moreover, a large array of genes responsible for increased metal tolerance, metal uptake and hyperaccumulation have already been identified. Thus, the CRISPR-mediated genome reprogramming of plants, including its use in gene expression regulation through transcriptional repression or activation (CRISPRi and CRISPRa), could be of paramount importance for phytoremediation. The simplicity, inexpensiveness, and capabilities of this gene editing technique could soon be used to enhance plants and bacteria involved in phytotechnologies, such as phystabilization, phytoextraction, phytomining, phytovolatilization, and bio-energy generation. In this brief viewpoint piece, we posit some of the potential benefits of CRISPR for phytoremediation.

18.
Environ Sci Pollut Res Int ; 25(21): 21243-21250, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29931643

RESUMEN

Rhenium (Re) is one of Earth's scarcest and more largely scattered elements, with an estimate concentration of 0.4-0.6 µg kg-1 in the upper crust. Still, considerable concentrations of bioavailable ReO4- ions are often found, particularly in copper-molybdenum mines, where their uptake by plants of these regions has been reported. Yet, the impact of Re on plants remains a question mark, as the only available knowledge derives from a limited investigation carried out over 60 years ago. The aim of this study was to evaluate the ecophysiological response of Brassica juncea, a species known to endure and accumulate various metals, to a broad range of Re concentrations. B. juncea plants were allowed to grow and on a substrate amended with KReO4 to attain soil Re levels ranging from 0 to 80 mg kg-1. Plants were collected 45 days after sowing for analysis. The results have shown that greater Re levels reduce growth, photosynthetic activity, soluble carbohydrate mobilization, and protein contents, and increase the plant's oxidative stress (anthocyanins, H2O2, lipid peroxidation) and corresponding response (ascorbic acid, superoxide dismutase activity). Nevertheless, B. juncea exhibited a remarkable ability to endure and uptake Re, featuring shoot Re concentrations that ranged from 1615 to 24,987 mg kg-1 among the 5 and 80 mg kg-1 treatments.


Asunto(s)
Planta de la Mostaza/efectos de los fármacos , Planta de la Mostaza/metabolismo , Renio/farmacocinética , Contaminantes del Suelo/farmacocinética , Ácido Ascórbico/metabolismo , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Ecotoxicología/métodos , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Renio/administración & dosificación , Renio/toxicidad , Contaminantes del Suelo/toxicidad , Superóxido Dismutasa/metabolismo
19.
Expert Opin Drug Deliv ; 12(4): 507-12, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25425332

RESUMEN

Gene therapy has received much attention in the field of drug delivery. Synthetic, nonviral gene delivery systems have gained increasing attention as vectors for gene therapy mainly due to a favorable immunogenicity profile and ease of manufacturing as compared to viral vectors. The great majority of these formulations are based on polycationic structures, due to their ability to interact with negatively charged nucleic acids to spontaneously form nanoparticles. In recent years, several polycationic systems have demonstrated high transfection in vitro. However, progress toward clinical applications has been slow, mainly because the cationic nature of these systems leads to intolerable toxicity levels, inappropriate biodistribution and unsatisfactory efficiency in vivo, particularly after systemic administration. Decationized polyplexes are a new class of gene delivery systems that have been developed as an alternative for conventional polycation-based systems. The major innovation introduced by decationized polyplexes is that these systems are based on neutral polymers, without any detrimental effect on the physicochemical stability or encapsulation ability, due to the transient presence of cationic charge and disulfide cross-links between the polymer chains by which the nucleic acids are physically entrapped in the particles. This editorial summarizes the most important features of decationized polyplexes and discusses potential implications for the development of new safe and efficient gene delivery systems.


Asunto(s)
Terapia Genética/métodos , Vectores Genéticos/genética , Polímeros/química , Animales , Sistemas de Liberación de Medicamentos , Humanos , Nanopartículas , Distribución Tisular , Transfección
20.
Int J Phytoremediation ; 16(7-12): 704-18, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24933880

RESUMEN

Salinity is a major worldwide problem that affects agricultural soils and limits the reclamation of contaminated sites. Despite the large number of research papers published about salt tolerance in Brassica juncea L., there are very few accounts concerning the influence of salinity on the uptake of trace metals. In this study, B. juncea plants divided through soil sets comprising 0, 900 and 1800 mg Zn kg(-1), were treated with solutions containing 0, 60 and 120 mmol L(-1) of NaCl, with the purpose of observing the effect of salt on Zn uptake, and some physiological responses throughout the 90 days experiment. Increasing concentrations of NaCl and Zn produced a decline in the ecophysiological and biochemical properties of the plants, with observable synergistic effects on parameters like shoot dry weight, leaf area, or photochemical efficiency. Nevertheless, plants treated with 60 mmol L(-1) of NaCl accumulated striking harvestable amounts of Zn per plant that largely exceed those reported for Thlaspi caerulescens. It was concluded that salinity could play an important role on the uptake of Zn by B. juncea. The potential mechanisms behind these results are discussed, as well as the implications for phytoremediation of Zn on saline and non-saline soils.


Asunto(s)
Planta de la Mostaza/efectos de los fármacos , Cloruro de Sodio/farmacología , Contaminantes del Suelo/metabolismo , Zinc/metabolismo , Biodegradación Ambiental , Clorofila/análisis , Clorofila/metabolismo , Peróxido de Hidrógeno/análisis , Peróxido de Hidrógeno/metabolismo , Planta de la Mostaza/crecimiento & desarrollo , Planta de la Mostaza/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Salinidad , Sodio/análisis , Suelo/química , Contaminantes del Suelo/análisis , Estrés Fisiológico , Zinc/análisis
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