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1.
Phytopathology ; 112(9): 1998-2011, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35322716

RESUMEN

The devastating disease coffee leaf rust, caused by Hemileia vastatrix, has been a major constraint to worldwide coffee production. Recently, H. vastatrix populations were shown to be structured into three divergent genetic lineages with marked host specialization (C1, C2, and C3). However, there is yet no overall understanding of the population dynamics and adaptation of the most widespread and epidemiological relevant H. vastatrix group (C3). We used restriction site-associated DNA sequencing to generate 13,804 single nucleotide polymorphisms (SNPs) across a worldwide collection of 99 H. vastatrix isolates. Phylogenetic analyses uncovered a well-supported structuring within C3, with three main subgroups (SGs; SGI, SGII, and SGIII), which seem to reflect the historical distribution, breeding, and exchange of coffee cultivars. SGI shows a ladder-like diversification pattern and occurs across all four continents sampled, SGII is mainly restricted to Africa, and SGIII is observed only in Timor, revealing a higher genetic differentiation. Outlier and association tests globally identified 112 SNPs under putative positive selection, which impacted population structure. In particular, 29 overlapping SNPs per se seemed to have an extremely strong effect on H. vastatrix population divergence. We also found exclusive and fixed alleles associated with the SGs supporting local adaptation. Functional annotation revealed that transposable elements may play a role in host adaptation. Our study provides a higher-resolution perspective on the evolutionary history of H. vastatrix on cultivated coffee, showing its strong ability to adapt and the strength of the selective force imposed by coffee hosts, which should be taken into account when designing strategies for pathogen dissemination control and selective breeding.


Asunto(s)
Basidiomycota , Coffea , Basidiomycota/genética , Coffea/microbiología , Filogenia , Fitomejoramiento , Enfermedades de las Plantas/microbiología
2.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36430764

RESUMEN

Amino acids are crucial nutrients involved in several cellular and physiological processes, including fertilization and early embryo development. In particular, Leucine and Arginine have been shown to stimulate implantation, as lack of both in a blastocyst culture system is able to induce a dormant state in embryos. The aim of this work was to evaluate the effects of Leucine and Arginine withdrawal on pluripotent mouse embryonic stem cell status, notably, their growth, self-renewal, as well as glycolytic and oxidative metabolism. Our results show that the absence of both Leucine and Arginine does not affect mouse embryonic stem cell pluripotency, while reducing cell proliferation through cell-cycle arrest. Importantly, these effects are not related to Leukemia Inhibitory Factor (LIF) and are reversible when both amino acids are reconstituted in the culture media. Moreover, a lack of these amino acids is related to a reduction in glycolytic and oxidative metabolism and decreased protein translation in mouse embryonic stem cells (mESCs), while maintaining their pluripotent status.


Asunto(s)
Células Madre Embrionarias , Células Madre Embrionarias de Ratones , Animales , Ratones , Leucina/farmacología , Leucina/metabolismo , Arginina/farmacología , Arginina/metabolismo , Diferenciación Celular , Proliferación Celular
3.
Molecules ; 26(16)2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34443408

RESUMEN

Complex wastewater matrices present a major environmental concern. Besides the biodegradable organics, they may contain a great variety of toxic chemicals, heavy metals, and other xenobiotics. The electrochemically activated persulfate process, an efficient way to generate sulfate radicals, has been widely applied to the degradation of such complex effluents with very good results. This review presents the fundamentals of the electro-persulfate processes, highlighting the advantages and limitations, followed by an exhaustive evaluation on the application of this process for the treatment of complex industrial effluents. An overview of the main relevant experimental parameters/details and their influence on the organic load removal is presented and discussed, having in mind the application of these technologies at an industrial scale. Finally, the future perspectives for the application of the electro-persulfate processes in the treatment of complex wastewater matrices is outlined.

4.
Plant Dis ; 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33258426

RESUMEN

Cashew (Anacardium occidentale L.) is a cash crop with a highly significant economic importance in West Africa, particularly in Guinea-Bissau (Monteiro et al. 2015, 2017). In October 2018, dieback-like symptoms such as wilt and necrosis of apical shoots were observed in 10 % of the cashew trees grown in a 100 plant-orchard in Bolama Island at Bijagós archipelago, Guinea-Bissau. Six symptomatic apical shoots from individual plants were collected for fungal isolation and identification. Tissue pieces (3 × 2 mm) from healthy to diseased margins were surface sterilized with 1 % sodium hypochlorite, washed twice with sterilized water, placed on potato dextrose agar (PDA, Difco® Laboratories) supplemented with potassium thiocyanate (50 µg/ml), and incubated at 24 ± 1 °C in the dark for 7 days. Four fungal colonies were isolated (67 %) and purified through hyphal tips removal, displaying rapid growth rate, and aerial mycelia that initially was white, turning later to dark greenish on PDA. Pycnidia produced on 1.5 % water agar and sterilized pine needles (± 25ºC; near-UV light) were solitary, covered by mycelium, obpyriform to ampulliform (152.5 ± 41.6 × 135.2 ± 30.8 µm, n = 30). Conidia were unicellular, hyaline, smooth, fusoid to ovoid, thin-walled, measuring 16.21 ± 1.52 × 5.84 ± 0.66 µm (n = 50, L/W 2.8). Such morphological features are characteristic of Neofusicoccum spp. (Phillips et al. 2013). For molecular identification, genomic DNA was extracted from a representative isolate GB160 and partial regions of ribosomal internal transcriber spacer (ITS) (ITS1/ITS4; White et al. 1990), translation elongation factor 1-α (EF1-α) (EF1-688F/EF1-1251R; Alves et al. 2008) and ß-tubulin (ß-tub) (Bt2a/Bt2b; Glass and Donaldson 1995) genes were amplified as previously described, respectively, with BSA (50 mg/ml). Amplicons were sequenced and deposited in GenBank (ITS, MN952993; EF1-α, MN952204; ß-tub, MN952208). BLAST analysis of ITS, EF1-α and ß-tub gene sequences showed 100 % identity with Neofusicoccum batangarum reference strain CBS124923 (FJ900608, FJ900654, FJ900635, respectively). Maximum-likelihood and Bayesian Inference analyses from the concatenated dataset placed GB160 isolate within the N. batangarum cluster (BS = 72 %; PP = 0.95). For pathogenicity assessment, 3-month-old cashew "Caju di Terra" plants (n = 8) grown in a greenhouse under controlled conditions were inoculated following a randomized block design as described by Lima et al. (2013). Briefly, 3 mm diam. stem tissue bark was removed and replaced with a 3 mm diameter PDA plug retrieved from the colony margin. Inoculation wound was covered with sterilized wet cotton and sealed with parafilm. Eight control plants were only treated with PDA plugs and the wound covered and sealed as described. After 15 days, all inoculated plants displayed similar symptoms to those observed in the field, and vascular lesions (10.8 ± 4.0 cm), whereas control plants remained symptomless. Koch's postulates were fulfilled by successful re-isolation of the pathogen from all inoculated stems and identification by morphology and gene sequencing. N. batangarum was identified associated with Anacardium spp. in Brazil (Netto et al. 2017) and recently reported as causing grapevine dieback in Brazil (Rêgo et al. 2020). To our knowledge, this is the first report of N. batangarum causing cashew dieback in Guinea-Bissau and West Africa. Occurrence of this disease may represent a significant impact for cashew production since this crop is the major agricultural commodity in Guinea-Bissau.

5.
Molecules ; 25(24)2020 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-33322793

RESUMEN

This paper studies the degradation of methiocarb, a highly hazardous pesticide found in waters and wastewaters, through an electro-Fenton process, using a boron-doped diamond anode and a carbon felt cathode; and evaluates its potential to reduce toxicity towards the model organism Daphnia magna. The influence of applied current density and type and concentration of added iron source, Fe2(SO4)3·5H2O or FeCl3·6H2O, is assessed in the degradation experiments of methiocarb aqueous solutions. The experimental results show that electro-Fenton can be successfully used to degrade methiocarb and to reduce its high toxicity towards D. magna. Total methiocarb removal is achieved at the applied electric charge of 90 C, and a 450× reduction in the acute toxicity towards D. magna, on average, from approximately 900 toxic units to 2 toxic units, is observed at the end of the experiments. No significant differences are found between the two iron sources studied. At the lowest applied anodic current density, 12.5 A m-2, an increase in iron concentration led to lower methiocarb removal rates, but the opposite is found at the highest applied current densities. The highest organic carbon removal is obtained at the lowest applied current density and added iron concentration.


Asunto(s)
Biodegradación Ambiental , Insecticidas/metabolismo , Metiocarb/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Daphnia/efectos de los fármacos , Ecotoxicología/métodos , Electroquímica/métodos , Electrodos , Insecticidas/química , Insecticidas/toxicidad , Metiocarb/química , Metiocarb/toxicidad
6.
Cureus ; 16(2): e53893, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38468986

RESUMEN

Cytomegalovirus (CMV), a member of the Herpesviridae family, typically causes asymptomatic infections or mild mononucleosis-like syndromes in immunocompetent individuals. However, severe manifestations are well-documented in immunocompromised populations. This case report presents a previously healthy seven-year-old girl with a rare and complex presentation of primary CMV infection leading to severe multiorgan involvement, hepatosplenomegaly, cholestasis, bicytopenia, and a prolonged disease course. The patient's condition prompted an exhaustive diagnostic investigation, ruling out other potential causes. The diagnosis was confirmed by positive CMV IgM and IgG antibodies and a significantly elevated CMV DNA viral load. Treatment with intravenous ganciclovir resulted in a remarkable recovery. The case underscores the importance of considering CMV as a potential etiology of hepatitis, even in immunocompetent children, and the challenges of diagnosing complicated CMV infections. While guidelines for treating CMV in immunocompetent individuals are lacking, this report suggests that antiviral therapy may be beneficial in severe cases. Further research is needed to establish clear treatment protocols for such instances. This report contributes to the limited body of literature on severe CMV-induced hepatitis in immunocompetent children, emphasizing the need for heightened clinical awareness and timely interventions to prevent progression to acute liver failure.

7.
Sci Rep ; 14(1): 8561, 2024 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609468

RESUMEN

Trauma scientists have raised the alarm about the devastating consequences of the Ukraine war on mental health. We examined how higher education students-as indirect victims-coped with this conflict and how they emotionally reacted during 2022. We involved 2314 students from 16 countries through an online survey. A structural equation model indicated significant relations between war-related worry about military and macroeconomics domains and two coping strategies (opposition, support giving), in turn significantly linked with six emotions. The model was strongly invariant across gender, study field, and geographic area. The most frequent emotions were anger and anxiety, followed by two future-centred emotions (hopelessness and hope). Emotions were more frequent for females and students of the countries geographically close to the war region. Our findings call for evidence-based policy recommendations to be implemented by institutions to combat the negative short and long-term psychological sequelae of being witnesses of armed conflicts.


Asunto(s)
Ansiedad , Emociones , Femenino , Humanos , Ucrania , Habilidades de Afrontamiento , Estudiantes
8.
Biology (Basel) ; 12(2)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36829425

RESUMEN

Geographic location and, particularly, soil and climate exert influence on the typicality of a wine from a specific region, which is often justified by the terroir, and these factors also influence the epiphytic flora associated with the surface of the grape berries. In the present study, the microbiome associated with the surface of berries obtained from ten vineyards of the Alvarinho variety located in different geographical locations in mainland Portugal was determined and analyzed. The removal of microbial flora from the surface of the berries was carried out by washing and sonication, after which the extraction and purification of the respective DNA was carried out. High-throughput short amplicon sequencing of the fungal ITS region and the bacterial 16S region was performed, allowing for the determination of the microbial consortium associated with Alvarinho wine grapes. Analysis of α-diversity demonstrated that parcels from the Monção and Melgaço sub-region present a significantly (p < 0.05) lower fungal diversity and species richness when compared to the plots analyzed from other regions/sub-regions. The ubiquitous presence of Metschnikowia spp., a yeast with enologic potential interest in all parcels from Monção and Melgaço, was also observed.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36673723

RESUMEN

At least 50% of chronic disease patients don't follow their care plans, leading to lower health outcomes and higher medical costs. Providing Patient Education Materials (PEMs) to individuals living with a disease can help to overcome these problems. PEMs are especially beneficial for people suffering from multisystemic and underrecognized diseases, such as rare diseases. Congenital disorders of glycosylation (CDG) are ultra-rare diseases, where a need was identified for PEMs in plain language that can clearly explain complex information. Community involvement in the design of PEMs is extremely important for diseases whose needs are underserved, such as rare diseases; however, attempts to involve lay and professional stakeholders are lacking. This paper presents a community-based participatory framework to co-create PEMs for CDG, that is transferable to other diseases. A literature review and questionnaire were performed, and only four articles describing the development of PEMS for rare diseases have been found, which demonstrates a lack of standardized approaches. The framework and PEMs were co-developed with CDG families and will be crucial in increasing health literacy and empowering families. We will close a gap in the creation of PEMs for CDG by delivering these resources in lay language in several languages.


Asunto(s)
Trastornos Congénitos de Glicosilación , Alfabetización en Salud , Humanos , Enfermedades Raras/terapia , Educación del Paciente como Asunto , Participación de la Comunidad
10.
Nanomaterials (Basel) ; 11(11)2021 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-34835908

RESUMEN

Perovskites of the (La,Ba)(Fe,Ti)O3 family were prepared, characterized, and utilized as heterogeneous photocatalysts, activated by natural sunlight, for environmental remediation of Acid Orange 7 (AO7) aqueous solutions. Catalysts were prepared by the ceramic (CM) and the complex polymerization (CP) methods and characterized by XRD, SEM, EDS, and band gap energy. It was found that catalytic properties depend on the synthesis method and annealing conditions. In the photocatalytic assays with sunlight, different AO7 initial concentrations and perovskite amounts were tested. During photocatalytic assays, AO7 and degradation products concentrations were followed by HPLC. Only photocatalysis with BaFeO3-CM and BaTiO3-CP presented AO7 removals higher than that observed for photolysis. However, photolysis leads to the formation of almost exclusively amino-naphthol and sulfanilic acid, whereas some of the perovskites utilized form less-toxic compounds as degradation products, such as carboxylic acids (CA). Partial substitution of Ba by La in BaTiO3-CM does not produce any change in the photocatalytic properties, but the replacement of Ti by Fe in the La0.1Ba0.9TiO3 leads to reduced AO7 removal rate, but with the formation of CAs. The best AO7 removal (92%) was obtained with BaFeO3-CM (750 mg L-1), after 4 h of photocatalytic degradation with solar radiation.

11.
Environ Sci Pollut Res Int ; 28(19): 23822-23832, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33145735

RESUMEN

Perovskite oxides BaFeyTi1-yO3, with y = 0, 0.6, 0.8 and 1, were prepared by ceramic (CM) and complex polymerization methods (CPM) and utilized in UV-LED (365 nm) photocatalytic degradation assays of 25 mg L-1 diclofenac (DIC) model solutions. BaTiO3-CM was also used in the photocatalytic degradation test of a real mineral water for human consumption spiked with 2 mg L-1 DIC. The XRD patterns of the synthesized perovskites showed cubic structure for those prepared by CPM, with distortions of the cubic lattice to hexagonal or tetragonal when prepared by CM, except for BaTiO3. All the perovskites showed good catalytic activity, higher than photolysis, except BaFeO3-CM that presented similar results. BaTiO3-CM and CPM and BaFeO3-CPM were also utilized in UV-LED photocatalytic DIC degradation assays with peroxydisulfate addition. BaFeO3-CPM and BaTiO3-CPM showed better ability to persulfate activation, but the highest mineralization degree was obtained with BaTiO3-CM. This last perovskite was also able to perform DIC degradation in a real matrix. The studied oxides show potentiality for photocatalytic degradation of organic compounds, with or without persulfate addition. A degradation mechanism is proposed.


Asunto(s)
Diclofenaco , Titanio , Compuestos de Calcio , Catálisis , Humanos , Óxidos , Fotólisis
12.
Cell Biochem Funct ; 28(3): 224-31, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20235330

RESUMEN

Mitochondrial proton leak can account for almost 20% of oxygen consumption and it is generally accepted that this process contributes to basal metabolism. In order to clarify the role of basal proton leak in testicular mitochondria, we performed a comparative study with kidney and liver mitochondrial fractions. Proton leak stimulated by linoleic acid and inhibited by guanosine diphosphate (GDP) was detected, in a manner that was correlated with protein levels for uncoupling protein 2 (UCP2) in the three fractions. Modulation of proton leak had an effect on reactive oxygen species production as well as on lipid peroxidation, and this effect was also tissue-dependent. However, a possible role for the adenine nucleotide transporter (ANT) in testicular mitochondria proton leak could not be excluded. The modulation of proton leak appears as a possible and attractive target to control oxidative stress with implications for male gametogenesis.


Asunto(s)
Peroxidación de Lípido , Mitocondrias/metabolismo , Protones , Especies Reactivas de Oxígeno/metabolismo , Testículo/citología , Animales , Guanosina Difosfato/metabolismo , Peróxido de Hidrógeno/metabolismo , Canales Iónicos/metabolismo , Riñón/citología , Ácido Linoleico/metabolismo , Masculino , Potencial de la Membrana Mitocondrial/fisiología , Mitocondrias Hepáticas/metabolismo , Proteínas Mitocondriales/metabolismo , Oxidantes/metabolismo , Fosforilación Oxidativa , Estrés Oxidativo , Consumo de Oxígeno , Ratas , Ratas Wistar , Proteína Desacopladora 2
13.
Biochim Biophys Acta Mol Basis Dis ; 1866(7): 165760, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32151634

RESUMEN

Metabolism, is a transversal hot research topic in different areas, resulting in the integration of cellular needs with external cues, involving a highly coordinated set of activities in which nutrients are converted into building blocks for macromolecules, energy currencies and biomass. Importantly, cells can adjust different metabolic pathways defining its cellular identity. Both cancer cell and embryonic stem cells share the common hallmark of high proliferative ability but while the first represent a huge social-economic burden the second symbolize a huge promise. Importantly, research on both fields points out that stem cells share common metabolic strategies with cancer cells to maintain their identity as well as proliferative capability and, vice versa cancer cells also share common strategies regarding pluripotent markers. Moreover, the Warburg effect can be found in highly proliferative non-cancer stem cells as well as in embryonic stem cells that are primed towards differentiation, while a bivalent metabolism is characteristic of embryonic stem cells that are in a true naïve pluripotent state and cancer stem cells can also range from glycolysis to oxidative phosphorylation. Therefore, this review aims to highlight major metabolic similarities between cancer cells and embryonic stem cells demonstrating that they have similar strategies in both signaling pathways regulation as well as metabolic profiles while focusing on key metabolites.


Asunto(s)
Diferenciación Celular/genética , Células Madre Embrionarias/metabolismo , Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , Metabolismo Energético/genética , Glucólisis/genética , Humanos , Redes y Vías Metabólicas/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Neoplasias/patología , Células Madre Neoplásicas/patología , Fosforilación Oxidativa
14.
Stem Cells Int ; 2020: 8835353, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33123203

RESUMEN

DMSO is a commonly used solvent in biological studies, as it is an amphipathic molecule soluble in both aqueous and organic media. For that reason, it is the vehicle of choice for several water-insoluble substances used in research. At the molecular and cellular level, DMSO is a hydrogen-bound disrupter, an intercellular electrical uncoupler, and a cryoprotectant, among other properties. Importantly, DMSO often has overlooked side effects. In stem cell research, the literature is scarce, but there are reports on the effect of DMSO in human embryoid body differentiation and on human pluripotent stem cell priming towards differentiation, via modulation of cell cycle. However, in mouse embryonic stem cell (mESC) culture, there is almost no available information. Taking into consideration the almost ubiquitous use of DMSO in experiments involving mESCs, we aimed to understand the effect of very low doses of DMSO (0.0001%-0.2%), usually used to introduce pharmacological inhibitors/modulators, in mESCs cultured in two different media (2i and FBS-based media). Our results show that in the E14Tg2a mESC line used in this study, even the smallest concentration of DMSO had minor effects on the total number of cells in serum-cultured mESCs. However, these effects could not be explained by alterations in cell cycle or apoptosis. Furthermore, DMSO did not affect pluripotency or differentiation potential. All things considered, and although control experiments should be carried out in each cell line that is used, it is reasonable to conclude that DMSO at the concentrations used here has a minimal effect on this particular mESC line.

15.
Biochim Biophys Acta Gen Subj ; 1864(8): 129612, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32272203

RESUMEN

Embryonic diapause is a conserved reproductive strategy in which development arrests at the blastocyst phase. Recently mammalian target of rapamycin (mTOR) inhibition was shown to induce diapause on mouse blastocysts and a paused-like state on mouse embryonic stem cells (mESCs). In this work, we aimed to further characterize this new paused-pluripotent state, focusing on its glycolytic and oxidative metabolic function. We therefore exposed mESCs, to the mTOR inhibitor INK-128 and evaluated proliferation, pluripotency status and energy-related metabolism, as well as the mTOR inhibition status and translational function. Unexpectedly, in our hands INK-128 did not inhibit the phosphorylation of mTOR or its downstream targets after 48 h. Accordingly, no alterations on protein translational function were observed. Nonetheless, INK-128 could still successfully induce a paused-like state in naïve mESCs regardless of their culturing conditions, by greatly slowing proliferation without affecting pluripotency status. This effect was more prevalent in 2i cultured cells. Interestingly, in this paused-like state, mESCs present a glucose-related hypometabolic profile, which is a hallmark of diapaused blastocysts, with decreased glycolytic and oxidative metabolism and decreased nutrient uptake. Despite the lack of mTOR inhibition and translational suppression, INK-128 still induced a paused-like pluripotent state through cell cycle and metabolic modulation, rather than by translational suppression, suggesting more than one avenue for this type of pluripotent phenotype.


Asunto(s)
Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Animales , Benzoxazoles/farmacología , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Metabolismo Energético , Ratones , Células Madre Pluripotentes/efectos de los fármacos , Pirimidinas/farmacología , Serina-Treonina Quinasas TOR/metabolismo
16.
J Colloid Interface Sci ; 561: 609-619, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31757448

RESUMEN

Mesoporous silica nanoparticles (MSNs) feature ideal structural properties and surface chemistry for use as nanocarriers of molecules, polymers and biomolecules in cutting-edge applications. One important challenge remaining in their preparation is the ability to tune their diameter in the range of a few tens of nanometers, with narrow size dispersity, preferably using a simple, sustainable and scalable synthetic process. This work presents a fully controllable low-temperature and purely aqueous sol-gel method to prepare MSNs with user-defined diameters from 15 nm to 80 nm and narrow size dispersity. The method also allows modification of the pore structure and offers the possibility of incorporating a luminescent species in the silica network for optical traceability. Control was achieved by tuning the colloidal stability of the assembly of cylindrical micelles that template the MSN synthesis. Using CTAB cylindrical micelles as template and sodium hydroxide (NaOH) as catalyst, precise diameter control was achieved either by changing the pH (that controls micelle surface charge) or by adding salt at constant pH (to tune the ionic strength and charge screening). This new sustainable MSN synthesis method provides full control over the nanoparticle diameters and can be used as a platform for the application of MSNs with user-defined sizes in different fields.

17.
J Chromatogr Sci ; 47(5): 387-91, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19476707

RESUMEN

A high-performance liquid chromatography-UV methodology (lambda=230 nm) was developed and validated for the simultaneous determination of vincristine and doxorubicin in pharmaceutical preparations used in oncology. The chromatography was carried out on a C18 column using acetonitrile 90% in water-potassium hydrogenphosphate buffer 50 mM, pH 3.2+/-0.1 (32:68, v/v) as mobile phase at a flow rate of 1.5 mL/min. The method proved to be specific, exact, and accurate, in accordance with the ICH standards, presenting linearity in the 1-5 microg/mL and 5-100 microg/mL intervals, and detection (0.19x0.51 microg/mL) and quantification (0.63x1.7 microg/mL) limits for vincristine and doxorubicin, respectively.


Asunto(s)
Antineoplásicos/análisis , Cromatografía Líquida de Alta Presión/métodos , Doxorrubicina/análisis , Preparaciones Farmacéuticas/química , Espectrofotometría Ultravioleta/métodos , Vincristina/análisis , Concentración de Iones de Hidrógeno , Estándares de Referencia , Reproducibilidad de los Resultados
18.
Environ Sci Pollut Res Int ; 26(1): 24-33, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29961224

RESUMEN

In this study, the efficiency of electrochemical oxidation to treat a sanitary landfill leachate was evaluated by the reduction in physico-chemical parameters and in ecotoxicity. The acute toxicity of the sanitary landfill leachates, before and after treatment, was assessed with the model organism Daphnia magna. Electrochemical oxidation treatment was effective in the removal of organic load and ammonium nitrogen and in the reduction of metal ions concentrations. Furthermore, a reduction of 2.5-fold in the acute toxicity towards D. magna after 36 h of treatment was noticed. Nevertheless, the toxicity of the treated leachate is still very high, and further treatments are necessary in order to obtain a non-toxic effluent to this aquatic organism. Toxicity results were also compared with others described in the literature for different leachate treatments and test organisms.


Asunto(s)
Técnicas Electroquímicas/métodos , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Amoníaco/análisis , Amoníaco/toxicidad , Animales , Análisis de la Demanda Biológica de Oxígeno , Daphnia/efectos de los fármacos , Ecotoxicología , Nitrógeno/análisis , Nitrógeno/toxicidad , Oxidación-Reducción , Contaminantes Químicos del Agua/toxicidad
19.
Anim Reprod Sci ; 106(1-2): 36-47, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17451892

RESUMEN

The goal of this work was to correlate oxidative stress caused by reactive oxygen species (ROS) and DNA damage with classic semen parameters in spermatozoa and seminal plasma of fertile and subfertile stallions. Oxidation was measured in both lipids and proteins, using the thiobarbituric acid reactive species (TBARS) assay and the DNPH carbonyl groups assay, respectively. Sperm DNA damage was monitored using the TUNEL assay. These parameters were monitored in samples obtained during the breeding and the non-breeding seasons. In general, fertile stallions showed better classical semen parameters, and those parameters improved from the non-breeding to the breeding season, although an increase in sperm production was accompanied by a decrease in the semen quality from subfertile stallions in the breeding season. In terms of oxidation levels we found that there were clear differences whether lipids or proteins were considered. In the breeding season there seemed to be a tendency towards normalizing lipid oxidation in spermatozoa and seminal plasma, and protein oxidation in the seminal plasma, of both fertile and subfertile animals. Thus, differences monitored in the non-breeding season were no longer visible. Interestingly, a higher level of protein oxidation was found in the sperm of fertile animals in the breeding season. Considering that there were positive correlations between sperm protein oxidation and sperm motility and vitality, these results suggests that the oxidation of semen proteins may be important for sperm function. On the other hand, lipid oxidation in the seminal plasma seemed to be a general indicator for sperm damage. In the non-breeding season positive correlations between lipid and protein oxidation levels in both sperm and seminal plasma and several defects in sperm function were found, but only for subfertile animals, thus suggesting that lipid and protein oxidation may aid in the identification of subfertile stallions during the non-breeding season. Levels of ROS production never seemed to result in compromised sperm DNA integrity, indicating that measurements were within physiological levels and/or that there is an efficient antioxidant activity in stallion sperm cells.


Asunto(s)
Roturas del ADN de Doble Cadena , Fertilidad/fisiología , Caballos/fisiología , Lípidos/análisis , Proteínas/metabolismo , Estaciones del Año , Semen/química , Espermatozoides/química , Acrosoma/fisiología , Animales , Cruzamiento , Fertilidad/genética , Caballos/genética , Masculino , Oxidación-Reducción , Proteínas/análisis , Semen/metabolismo , Espermatozoides/metabolismo
20.
Rev Bras Ortop ; 52(3): 242-250, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28702380

RESUMEN

Total knee arthroplasty (TKA) is a surgical procedure of paramount relevance that restores a substantial degree of function in arthritic knees. Increased consideration has been given to the influence of limb alignment on longevity after TKA, as errors in component placement can be associated with inferior function and compromised long-term performance. Consequently, numerous studies comparing patient-specific instrumentation (PSI) to standard instruments (SI) have been published. Patient-specific approaches use preoperative imaging to create specific materials for each patient's anatomy and were designed to achieve a higher rate of success in TKA, causing the entire procedure to be more efficient and cost-effective. However, it is not clear to what degree these studies support the potential advantages of PSI. Thus, the present study aimed to review the current evidence comparing PSI to SI, concerning alignment, cost-effectiveness, and postoperative functional evaluation.


A artroplastia total do joelho (ATJ) é um procedimento cirúrgico de fundamental relevância que restaura boa parte da função de joelhos artríticos. Maior atenção tem sido dada à influência do alinhamento do membro na longevidade após a ATJ, uma vez que erros no posicionamento dos componentes podem estar associados à uma menor função e compromentimento do desempenho a longo prazo. Consequentemente, vários estudos compararam a instrumentação personalizada para cada paciente (IPP) com a instrumentação padrão (IP). As abordagens personalizadas usam imagens pré-operatórias para criar materiais específicos para a anatomia de cada paciente e foram projetados para atingir uma maior taxa de sucesso na ATJ, tornando todo o processo mais eficiente e rentável. No entanto, não está claro até que ponto tais estudos respaldam as vantagens potenciais da IPP. Assim, o presente estudo teve como objetivo avaliar as evidências atuais, comparando IPP e IP em respeito ao alinhamento, relação custo-benefício e avaliação funcional pós-operatória.

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