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1.
Int J Mol Sci ; 24(5)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36902208

RESUMEN

Red LED light (R LED) is an efficient tool to improve seed germination and plant growth under controlled environments since it is more readily absorbed by photoreceptors' phytochromes compared to other wavelengths of the spectrum. In this work, the effect of R LED on the radicle emergence and growth (Phase III of germination) of pepper seeds was evaluated. Thus, the impact of R LED on water transport through different intrinsic membrane proteins, via aquaporin (AQP) isoforms, was determined. In addition, the remobilization of distinct metabolites such as amino acids, sugars, organic acids, and hormones was analysed. R LED induced a higher germination speed index, regulated by an increased water uptake. PIP2;3 and PIP2;5 aquaporin isoforms were highly expressed and could contribute to a faster and more effective hydration of embryo tissues, leading to a reduction of the germination time. By contrast, TIP1;7, TIP1;8, TIP3;1 and TIP3;2 gene expressions were reduced in R LED-treated seeds, pointing to a lower need for protein remobilization. NIP4;5 and XIP1;1 were also involved in radicle growth but their role needs to be elucidated. In addition, R LED induced changes in amino acids and organic acids as well as sugars. Therefore, an advanced metabolome oriented to a higher energetic metabolism was observed, conditioning better seed germination performance together with a rapid water flux.


Asunto(s)
Acuaporinas , Capsicum , Capsicum/metabolismo , Semillas/metabolismo , Germinación , Isoformas de Proteínas/metabolismo , Acuaporinas/metabolismo , Hormonas/metabolismo , Homeostasis , Agua/metabolismo , Azúcares/metabolismo , Aminoácidos/metabolismo
2.
ACS Nano ; 18(22): 14145-14160, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38761153

RESUMEN

Glioblastoma (GBM) is a primary malignant brain tumor with limited therapeutic options. One promising approach is local drug delivery, but the efficacy is hindered by limited diffusion and retention. To address this, we synthesized and developed a dual-sensitive nanoparticle (Dual-NP) system, formed between a dendrimer and dextran NPs, bound by a dual-sensitive [matrix metalloproteinase (MMP) and pH] linker designed to disassemble rapidly in the tumor microenvironment. The disassembly prompts the in situ formation of nanogels via a Schiff base reaction, prolonging Dual-NP retention and releasing small doxorubicin (Dox)-conjugated dendrimer NPs over time. The Dual-NPs were able to penetrate deep into 3D spheroid models and detected at the tumor site up to 6 days after a single intratumoral injection in an orthotopic mouse model of GBM. The prolonged presence of Dual-NPs in the tumor tissue resulted in a significant delay in tumor growth and an overall increase in survival compared to untreated or Dox-conjugated dendrimer NPs alone. This Dual-NP system has the potential to deliver a range of therapeutics for efficiently treating GBM and other solid tumors.


Asunto(s)
Neoplasias Encefálicas , Sistemas de Liberación de Medicamentos , Glioblastoma , Metaloproteinasas de la Matriz , Nanopartículas , Animales , Humanos , Ratones , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Dendrímeros/química , Dextranos/química , Doxorrubicina/farmacología , Doxorrubicina/química , Doxorrubicina/administración & dosificación , Portadores de Fármacos/síntesis química , Sistemas de Liberación de Medicamentos/métodos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Glioblastoma/metabolismo , Concentración de Iones de Hidrógeno , Metaloproteinasas de la Matriz/metabolismo , Ratones Desnudos , Nanopartículas/química , Microambiente Tumoral
3.
Environ Sci Technol ; 47(13): 7195-203, 2013 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-23710798

RESUMEN

The cycling of hexachlorobenzene (HCB) and hexachlorocyclohexanes (HCHs) has been studied in the North Atlantic and Arctic Ocean. Concentrations of HCHs and HCB were measured simultaneously in the atmosphere (gas and aerosol phases), seawater (dissolved and particulate phases), and phytoplankton. The atmospheric concentrations of HCHs decrease during transport over the Greenland Current with estimated e-folding times of 1.6 days, a trend not observed for HCB. This strong decrease in atmospheric concentrations of HCH is consistent with the estimated atmospheric depositional fluxes driven by the air-water disequilibrium. The removal of HCHs from the surface ocean by the degradative pump due to hydrolysis and microbial degradation and by the biological pump due to settling of particle-associated HCHs are estimated; the removal fluxes are within a factor of 2 of the atmospheric inputs for most sampling events, suggesting an important role of the degradative pump in the overall oceanic sink of HCHs. Conversely, the lack of degradation of HCB in surface waters and its relatively low hydrophobicity imply a lack of effective removal processes, consistent with the observed air and water concentrations close to equilibrium. This work is the first that estimates the relative importance of the biological and degradative pumps on the atmospheric deposition of the less persistent organic pollutants and points out the need for further research for quantifying the magnitude of degradative processes in the environment.


Asunto(s)
Contaminantes Atmosféricos/análisis , Hexaclorobenceno/análisis , Hexaclorociclohexano/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Atmosféricos/química , Contaminantes Atmosféricos/metabolismo , Regiones Árticas , Bacterias/metabolismo , Hexaclorobenceno/química , Hexaclorobenceno/metabolismo , Hexaclorociclohexano/química , Hexaclorociclohexano/metabolismo , Hidrólisis , Océanos y Mares , Fitoplancton/química , Agua de Mar/análisis , Agua de Mar/microbiología , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo
4.
Environ Sci Technol ; 47(11): 5578-87, 2013 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-23627767

RESUMEN

The Southern Ocean is one of the most pristine environments in the world, but is nonetheless affected by inputs of persistent organic pollutants (POPs). In the present work, we report the concentrations of hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), and 26 polychlorinated biphenyl (PCBs) congeners in seawater and phytoplankton from samples obtained during three Antarctic cruises in 2005, 2008, and 2009. The levels of PCBs, HCHs, and HCB are low in comparison to the few previous reports for this region and studies from other oceans. The long-term decline of POP concentrations in the Southern Ocean seawater since early 1980 is consistent with half-lives of 3.4 and 5.7 years for HCHs and PCBs, respectively. There is a large variability of PCBs, HCHs, and HCB concentrations in water and phytoplankton within the Bransfield Strait, South Scotia, Weddell, and Bellingshausen Seas that masks the differences between the studied Seas. However, the variability of PCBs concentrations in phytoplankton is significantly correlated with phytoplankton biomass, with lower concentrations in the most productive waters. This trend is more apparent for the more hydrophobic congeners, consistent with the role of settling fluxes of organic matter decreasing the concentrations of hydrophobic POPs in productive waters. The present work reports the most extensive data set on concentrations in seawater and phytoplankton for the Southern Ocean, and points to the important biogeochemical drivers, such as settling and degradation, influencing the occurrence of POPs in the ocean.


Asunto(s)
Hexaclorobenceno/análisis , Hexaclorociclohexano/análisis , Fitoplancton/química , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Regiones Antárticas , Océanos y Mares , Plaguicidas/análisis , Agua de Mar/análisis
5.
J Appl Microbiol ; 115(1): 218-35, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23594253

RESUMEN

AIMS: A structural and functional study has been carried out in the rice production area of the Guadalquivir marshes in southern Spain aiming to increase knowledge of rice rhizosphere structure and function for further application on integrated management practices. METHODS AND RESULTS: Rhizosphere bacterial structure (analysis of 16S rRNA partial sequences from total soil DNA), metabolic diversity (analysed by Biolog FF for fungal community and GN for microbial community) and a screening for putative plant growth-promoting rhizobacteria (PGPR) to identify potential isolates for development of local biofertilizers, and biodiversity of culturable micro-organisms (analysis of 16S rRNA partial sequences) from four areas differing in salinity and Magnaporthe oryzae incidence in two moments of the crop cycle were studied. Results indicate that the dominant taxon in libraries from the four areas was Proteobacteria. Metabolic diversity was higher in areas affected only by salinity or incidence of Magnaporthe than in the control or area affected by both stresses. It seems that rice plants selected, in their rhizosphere, micro-organisms able to affect plant hormonal balance under all conditions, and this activity relied in different bacterial genera depending on the environmental stress. CONCLUSIONS: Bacterial genera for each stress, as well as generalist strains, were found present in all the studied areas. Potential molecular markers and taxonomic markers (Sphingobacteria for salt and Thermococci for Magnaporthe) of the different stress situations have been highlighted, and Class Verrucomicrobiae could be a marker for nonstressed areas. In addition, putative PGPR strains isolated in this study could be used as biofertilizers. SIGNIFICANCE AND IMPACT OF THE STUDY: Rice paddies are great ecologically important ecosystems. The results are very relevant as they may be included in the process of rice production, improving crop conditions with less environmental impact.


Asunto(s)
Bacterias/clasificación , Oryza/crecimiento & desarrollo , Oryza/microbiología , Rizosfera , Microbiología del Suelo , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Biodiversidad , Magnaporthe/aislamiento & purificación , ARN Ribosómico 16S/genética , Salinidad , España , Estrés Fisiológico
6.
Metabolites ; 13(10)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37887404

RESUMEN

In this investigation, we outline the applications of a data mining technique known as Subgroup Discovery (SD) to the analysis of a sample size-limited metabolomics-based dataset. The SD technique utilized a supervised learning strategy, which lies midway between classificational and descriptive criteria, in which given the descriptive property of a dataset (i.e., the response target variable of interest), the primary objective was to discover subgroups with behaviours that are distinguishable from those of the complete set (albeit with a differential statistical distribution). These approaches have, for the first time, been successfully employed for the analysis of aromatic metabolite patterns within an NMR-based urinary dataset collected from a small cohort of patients with the lysosomal storage disorder Niemann-Pick class 1 (NPC1) disease (n = 12) and utilized to distinguish these from a larger number of heterozygous (parental) control participants. These subgroup discovery strategies discovered two different NPC1 disease-specific metabolically sequential rules which permitted the reliable identification of NPC1 patients; the first of these involved 'normal' (intermediate) urinary concentrations of xanthurenate, 4-aminobenzoate, hippurate and quinaldate, and disease-downregulated levels of nicotinate and trigonelline, whereas the second comprised 'normal' 4-aminobenzoate, indoxyl sulphate, hippurate, 3-methylhistidine and quinaldate concentrations, and again downregulated nicotinate and trigonelline levels. Correspondingly, a series of five subgroup rules were generated for the heterozygous carrier control group, and 'biomarkers' featured in these included low histidine, 1-methylnicotinamide and 4-aminobenzoate concentrations, together with 'normal' levels of hippurate, hypoxanthine, quinolinate and hypoxanthine. These significant disease group-specific rules were consistent with imbalances in the combined tryptophan-nicotinamide, tryptophan, kynurenine and tyrosine metabolic pathways, along with dysregulations in those featuring histidine, 3-methylhistidine and 4-hydroxybenzoate. In principle, the novel subgroup discovery approach employed here should also be readily applicable to solving metabolomics-type problems of this nature which feature rare disease classification groupings with only limited patient participant and sample sizes available.

7.
Sci Rep ; 13(1): 19663, 2023 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-37952061

RESUMEN

Despite evidence from grasslands experiments suggesting that plant species loss reduces biomass production, the strength of biodiversity-ecosystem functioning relationships in managed grasslands is still debated. High land-use intensity and reduced species pools are often suggested to make relationships between biodiversity and productivity less positive or even negative, but concrete evidence is still scarce. We investigated biodiversity-productivity relationships over two years in 150 managed grasslands in Germany. Specifically, we distinguished between relationships of biodiversity and biomass production in managed grasslands (1) varying in land-use intensity (e.g. of mowing, grazing and/or fertilization), (2) where land-use intensity is experimentally reduced, and (3) where additionally to land-use reductions, species pools are enlarged by seed addition. Among grasslands varying in land-use intensity, we found negative biodiversity-productivity relationships. Land-use reduction weakened these relationships, towards neutral, and sometimes, even positive relationships. Seed addition reduced species pool limitations, but this did not strengthen biodiversity-productivity relationships. Our findings indicate that land-use intensity is an important factor explaining the predominantly negative biodiversity-productivity relationships in managed grasslands. While we did not find that species pool limitations weakened biodiversity-productivity relationships, our results are based on a two-year-old experiment, possibly such effects are only visible in the long-term. Ultimately, advancing insights on biodiversity-ecosystem functioning relationships helps us to understand under which conditions agricultural production may benefit from promoting biodiversity.


Asunto(s)
Ecosistema , Pradera , Biomasa , Biodiversidad , Semillas
8.
Adv Mater ; 35(23): e2207877, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36994935

RESUMEN

Patients diagnosed with osteosarcoma undergo extensive surgical intervention and chemotherapy resulting in dismal prognosis and compromised quality of life owing to poor bone regeneration, which is further compromised with chemotherapy delivery. This study aims to investigate if localized delivery of miR-29b-which is shown to promote bone formation by inducing osteoblast differentiation and also to suppress prostate and cervical tumor growth-can suppress osteosarcoma tumors whilst simultaneously normalizing the dysregulation of bone homeostasis caused by osteosarcoma. Thus, the therapeutic potential of microRNA (miR)-29b is studied to promote bone remodeling in an orthotopic model of osteosarcoma (rather than in bone defect models using healthy mice), and in the context of chemotherapy, that is clinically relevant. A formulation of miR-29b:nanoparticles are developed that are delivered via a hyaluronic-based hydrogel to enable local and sustained release of the therapy and to study the potential of attenuating tumor growth whilst normalizing bone homeostasis. It is found that when miR-29b is delivered along with systemic chemotherapy, compared to chemotherapy alone, the therapy provided a significant decrease in tumor burden, an increase in mouse survival, and a significant decrease in osteolysis thereby normalizing the dysregulation of bone lysis activity caused by the tumor.


Asunto(s)
Neoplasias Óseas , MicroARNs , Nanopartículas , Osteólisis , Osteosarcoma , Masculino , Ratones , Animales , Calidad de Vida , MicroARNs/genética , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/genética , Osteosarcoma/patología , Osteólisis/tratamiento farmacológico , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología
9.
Toxics ; 10(12)2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36548568

RESUMEN

Human pressure due to industrial and agricultural development has resulted in a biodiversity crisis. Environmental pollution is one of its drivers, including contamination of wildlife by chemicals emitted into the air, soil, and water. Chemicals released into the environment, even at low concentrations, may pose a negative effect on organisms. These chemicals might modify the synthesis, metabolism, and mode of action of hormones. This can lead to failures in reproduction, growth, and development of organisms potentially impacting their fitness. In this review, we focused on assessing the current knowledge on concentrations and possible effects of endocrine disruptor chemicals (metals, persistent organic pollutants, and others) in studies performed in South America, with findings at reproductive and thyroid levels. Our literature search revealed that most studies have focused on measuring the concentrations of compounds that act as endocrine disruptors in animals at the systemic level. However, few studies have evaluated the effects at a reproductive level, while information at thyroid disorders is scarce. Most studies have been conducted in fish by researchers from Brazil, Argentina, Chile, and Colombia. Comparison of results across studies is difficult due to the lack of standardization of units in the reported data. Future studies should prioritize research on emergent contaminants, evaluate effects on native species and the use of current available methods such as the OMICs. Additionally, there is a primary focus on organisms related to aquatic environments, and those inhabiting terrestrial environments are scarce or nonexistent. Finally, we highlight a lack of funding at a national level in the reviewed topic that may influence the observed low scientific productivity in several countries, which is often negatively associated with their percentage of protected areas.

10.
Int J Food Microbiol ; 374: 109736, 2022 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-35613497

RESUMEN

Escherichia coli is among the most prevalent food contaminant microorganisms that have evolved, generating variants based on their effects on the host; these include commensals or pathobiont strains. The last classifications of E. coli intestinal pathobionts found in this review are enteroinvasive, enterohemorrhagic, enteropathogenic, enterotoxigenic, diffusely adherent, and enteroaggregative strains. Meanwhile, the most ancestral are enteropathogenic and enteroaggregative, and the most contemporaries are the enterotoxigenic and enteroinvasive strains. These pathobionts have been proposed based on their infective mechanisms, including toxin production, adherence effects, and tissue damage. It is also evidenced that environmental stresses, including bacterial exposition to antibiotics and disinfectants, contribute to this evolution. Therefore, new antibacterial and antivirulence agents are being explored, mainly from natural sources. In this context, this review discusses the diversity of E. coli pathobionts, their participation in foodborne outbreaks, and strategies to survey and control their spread and virulence.


Asunto(s)
Escherichia coli Enteropatógena , Infecciones por Escherichia coli , Proteínas de Escherichia coli , Antibacterianos , Diarrea/microbiología , Escherichia coli/genética , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Inocuidad de los Alimentos , Humanos , Virulencia
11.
Ecotoxicol Environ Saf ; 73(4): 507-14, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20092897

RESUMEN

Three experiments were carried out to select the best extractant for use in the sequential elution technique, to enable extraction of Cu, Pb, V and Zn from the extracellular fraction of the terrestrial moss Pseudoscleropodium purum. The optimal concentrations of the extractants tested (CoCl(2), NiCl(2), Pb(NO(3))(2), SrCl(2), dimercaprol, EDTA, penicillamine) were determined on the basis of the maximum extraction of Zn achieved without any alteration of the plasma membrane. The capacity of these agents (at the optimal concentrations established) to extract the extracellular fractions of Cu, Pb, V and Zn was then evaluated. Extraction with 10mM EDTA is recommended for all 4 elements considered. As a second option, the use of 50mM penicillamine is recommended to extract Cu, 30 mM dimercaprol to extract Pb and V and 20 mM NiCl(2) to extract Zn. It was also concluded that these results cannot be extrapolated to other cryptogams, and that separate assays are required.


Asunto(s)
Bryopsida/química , Quelantes/análisis , Metales Pesados/análisis , Cationes/análisis , Cobre/análisis , Dimercaprol/análisis , Ácido Edético/análisis , Plomo/análisis , Penicilamina/análisis , Vanadio/análisis , Zinc/análisis
12.
Sci Total Environ ; 742: 140524, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-32619842

RESUMEN

Improving the food supply chain efficiency has been identified as an essential means to enhance food security, while reducing pressure on natural resources. Adequate food loss and waste (FLW) management has been proposed as an approach to meet these objectives. The main hypothesis of this study is to consider that the "strong fluctuations and short-term changes" on eating habits may have major consequences on potential FLW generation and management, as well as on GHG emissions, all taking into account the nutritional and the economic cost. Due to the exceptional lockdown measures imposed by the Spanish government, as a consequence of the emerging coronavirus disease, COVID-19, food production and consumption systems have undergone significant changes, which must be properly studied in order to propose strategies from the lessons learned. Taking Spain as a case study, the methodological approach included a deep analysis of the inputs and outputs of the Spanish food basket, the supply chain by means of a Material Flow Analysis, as well as an economic and comprehensive nutritional assessment, all under a life cycle thinking approach. The results reveal that during the first weeks of the COVID-19 lockdown, there was no significant adjustment in overall FLW generation, but a partial reallocation from extra-domestic consumption to households occurred (12% increase in household FLW). Moreover, the economic impact (+11%), GHG emissions (+10%), and the nutritional content (-8%) complete the multivariable impact profile that the COVID-19 outbreak had on FLW generation and management. Accordingly, this study once again highlights that measures aimed at reducing FLW, particularly in the household sector, are critical to make better use of food surpluses and FLW prevention and control, allowing us to confront future unforeseen scenarios.


Asunto(s)
Infecciones por Coronavirus , Pandemias , Neumonía Viral , Eliminación de Residuos , Administración de Residuos , Betacoronavirus , COVID-19 , Brotes de Enfermedades , Alimentos , Humanos , SARS-CoV-2 , España
13.
Arch Soc Esp Oftalmol ; 83(5): 325-7, 2008 May.
Artículo en Español | MEDLINE | ID: mdl-18464183

RESUMEN

CASE REPORT: We present case reports of two young patients suffering from full thickness traumatic macular holes resulting in visual impairment of more than 60%. Both showed anatomical and visual improvement whilst waiting for surgical treatment. DISCUSSION: Spontaneous closure of a traumatic macular hole is an unusual outcome. OCT and clinical follow up enabled monitoring of this resolution during a period of a few weeks. Complex surgery was thus avoided by a short observational period.


Asunto(s)
Retina/lesiones , Perforaciones de la Retina , Adolescente , Adulto , Humanos , Masculino , Remisión Espontánea , Perforaciones de la Retina/diagnóstico
14.
Sci Total Environ ; 610-611: 1487-1495, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28898957

RESUMEN

Persistent organic pollutants (POPs) reach Antarctica through atmospheric transport, oceanic currents, and to minor extent, by migratory animals. The Southern Ocean is a net sink for many POPs, with a key contribution of the settling fluxes of POPs bound to organic matter (biological pump). However, little is known about POP transfer through the food web in the Southern Ocean and Antarctic waters, where krill is an important ecological node. In this study, we assessed the occurrence of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) in Antarctic krill (Euphausia superba) from the Bellingshausen, South Scotia and Weddell Seas around the Antarctic Peninsula. The concentrations of PCDD/Fs, PBDEs and PCBs in krill showed a large variability and the average were higher (generally within a factor 3) than those previously reported for eastern Antarctica. This result highlights regional differences related to atmospheric transport and deposition, and also probable regional sources due to human activities. Bioaccumulation and biomagnification factors for PCBs in krill were estimated using previously reported phytoplankton and seawater concentrations for this region. These suggested a near water-krill equilibrium for PCBs, which was not observed for water-phytoplankton partitioning. The estimated removal settling fluxes of PCBs due to the biological pump were several orders of magnitude higher than the estimated fluxes of PCBs transferred from phytoplankton to krill.


Asunto(s)
Monitoreo del Ambiente , Euphausiacea/metabolismo , Cadena Alimentaria , Contaminantes Químicos del Agua/metabolismo , Animales , Regiones Antárticas , Dibenzofuranos Policlorados/metabolismo , Éteres Difenilos Halogenados/metabolismo , Océanos y Mares , Bifenilos Policlorados/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Agua de Mar
15.
Rev Esp Enferm Dig ; 99(1): 25-32, 2007 Jan.
Artículo en Español | MEDLINE | ID: mdl-17295595

RESUMEN

OBJECTIVE: An intestinal reperfusion study with two aims: a) to assess the usefulness of intestinal capillary blood flow measurement by laser-Doppler for intestinal reperfusion studies; and b) to compare the effects of racemic and levo forms of folinic acid in treating the syndrome. EXPERIMENTAL DESIGN: A murine model of intestinal ischemia by completely clamping the superior mesenteric artery for 90 minutes. A comparison was made of three treatment groups: saline, folinic acid, and levo-folinic acid. The following factors were analyzed: changes in biochemical parameters (levels of creatine kinase, lactic dehydrogenase, and alkaline phosphatase at 60 minutes, and at two and seven days after restoring blood flow), capillary flow in the jejunum and ileum by laser-Doppler (during ischemia and after the first hour of reperfusion), intestinal mucosa injury, and survival curve. RESULTS: Laser-Doppler provided reliable data on how the different treatments affected capillary flow during intestinal reperfusion. Levo-folinic acid improved capillary flow in the ileum after 25 minutes of reperfusion, and also reduced mucosal injury in the same stretch of intestine by the seventh day post-reperfusion (p<0.05). On the other hand, it produced an initial increase in serum enzymes during reperfusion, and did not modify survival. CONCLUSIONS: The changes observed in intestinal capillary blood flow measurement by laser-Doppler have similarities with the effects of drugs on pathological mucosal changes. We could not prove that the levo form of folinic acid has a stronger protective effect versus racemic folinic acid in intestinal ischemia-reperfusion syndrome.


Asunto(s)
Intestinos/irrigación sanguínea , Leucovorina/uso terapéutico , Daño por Reperfusión/tratamiento farmacológico , Animales , Capilares , Masculino , Ratas , Flujo Sanguíneo Regional , Daño por Reperfusión/enzimología
18.
J Mech Behav Biomed Mater ; 74: 304-314, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28648990

RESUMEN

Tonometers are intended to determine the intraocular pressure (IOP) and the quality of corneal tissue. In contrast to the physiological state of stress of the cornea, tonometers induce non-physiological bending stress. Recently, the use of a single experiment to calibrate a set of corneal mechanical properties was suggested to be an ill-posed problem. Thus, we propose a numerical-experimental protocol that uses inflation and indentation experiments simultaneously, restricting the optimization space to circumvent the ambiguity of the fitting. For the first time, both corneal behaviors, i.e., biaxial tension (physiological) and bending (non-physiological), are taken into account. The experimental protocol was performed using an animal model (New Zealand rabbit's cornea). The patient-specific geometry and IOP were registered using a MODI topographer (CSO, Italy) and an applanation tonometer, respectively. The mechanical response was evaluated using inflation and indentation experiments. Subsequently, the optimal set of material properties is identified via an inverse finite element method. To validate the methodology, an in vivo incisional refractive surgery (astigmatic keratotomy, AK) is performed on four animals. The optical outcomes showed a good agreement between the real and simulated surgeries, indicating that the protocol can provide a reliable set of mechanical properties that enables further applications and simulations. After a reliable ex vivo database of inflation experiments is built, our protocol could be extended to humans.


Asunto(s)
Astigmatismo/cirugía , Córnea/cirugía , Presión Intraocular , Queratotomía Radial , Animales , Humanos , Modelos Teóricos , Conejos , Tonometría Ocular
19.
Int J Antimicrob Agents ; 50(3): 325-333, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28709990

RESUMEN

The aim of this study was to develop an in-vitro topical treatment for Acanthamoeba keratitis (AK) effective against cysts and trophozoites. Qualitative assays were performed with voriconazole, chlorhexidine, propamidine, cellulase, tobramycin, ciprofloxacin and paromomycin as monotherapy and various combinations. Riboflavin with ultraviolet-A (R + UV-A) as monotherapy or combined with voriconazole and moxifloxacin was also tested. Quantitative assays to assess cyst viability after treatment were performed for the chemicals that showed the highest activity in the qualitative assays. Paromomycin and propamidine did not show antiamoebic activity. Regardless of the total dose, no amoebicidal effect was observed for R + UV-A. Tobramycin, ciprofloxacin, voriconazole, chlorhexidine and cellulase were selected for quantitative assays because they appeared to cause greater damage to the structure of amoebae. Chlorhexidine and ciprofloxacin were the most active against Acanthamoeba spp. as monotherapy. Among the combinations evaluated, ciprofloxacin-voriconazole-chlorhexidine showed the greatest amoebicidal activity, with severe damage of the cellular membrane and an important decrease in cell concentration. In summary, ciprofloxacin as monotherapy and in combination with voriconazole and chlorhexidine has been classified as promising treatment. Additional in-vivo studies in animal models and clinical trials in patients with AK should be considered to confirm the efficacy of ciprofloxacin.


Asunto(s)
Queratitis por Acanthamoeba/parasitología , Acanthamoeba/efectos de los fármacos , Antiprotozoarios/farmacología , Supervivencia Celular/efectos de los fármacos , Interacciones Farmacológicas , Humanos , Técnicas In Vitro
20.
Arch Soc Esp Oftalmol ; 81(4): 213-6, 2006 Apr.
Artículo en Español | MEDLINE | ID: mdl-16688645

RESUMEN

CLINICAL CASE: A 65-year-old man had been treated with eye-drops containing NSAIDs (Ketorolac). He developed conjunctival injection, edematous swelling of the eyelids and periorbital dermatitis due to a contact allergy. Allergy to NSAIDs is uncommon. DISCUSSION: This is an unusual case because topical application of ketorolac is safe in the vast majority of ophthalmologic patients. However adverse events associated with Ketorolac are similar to that of other NSAIDs.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Dermatitis Atópica/inducido químicamente , Enfermedades de los Párpados/inducido químicamente , Ketorolaco Trometamina/efectos adversos , Administración Tópica , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/terapia , Erupciones por Medicamentos/diagnóstico , Erupciones por Medicamentos/etiología , Erupciones por Medicamentos/terapia , Enfermedades de los Párpados/diagnóstico , Enfermedades de los Párpados/terapia , Humanos , Ketorolaco Trometamina/administración & dosificación , Masculino , Soluciones Oftálmicas/administración & dosificación , Soluciones Oftálmicas/efectos adversos , Pruebas Cutáneas , Resultado del Tratamiento
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