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1.
Int J Gynecol Cancer ; 33(10): 1564-1571, 2023 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-37726197

RESUMEN

OBJECTIVES: The objective of our study was to describe the characteristics of patients with endometrial cancer diagnosed with a first recurrence involving the lung, and to describe the prognostic role of the molecular profile. We also aimed to describe the prognostic outcomes after local treatment of recurrence (resection of lung metastases or stereotactic body radiation therapy) in a group of patients with isolated lung recurrence. METHODS: This was a retrospective, single-center study between June 1995 and July 2021. The study included patients diagnosed with a first recurrence of endometrial cancer involving the lung. We defined two groups of patients: patients with isolated lung recurrence (confined to the lung) and patients with multisystemic recurrence (in the lung and other locations). RESULTS: Among 1413 patients diagnosed with endometrial cancer in stage IA to IVA of the International Federation of Gynecology and Obstetrics (FIGO) 2009, 64 (4.5%) patients had a first recurrence involving the lung. Of these, 15 (39.1%) were of a non-specific molecular profile, 16 (25%) were p53-abnormal, 15 (23.4%) were mismatch-repair deficient, and 0% POLE-mutated. P53-abnormal patients had the shortest 3 year progression-free survival after recurrence and those with mismatch-repair deficient had the longest 3 year progression-free survival (14.3% (range; 1.6-40.3) and 47.6% (range; 9.1-79.5) respectively, p=0.001). We found no differences on overall survival after recurrence by molecular profile. Thirty-one of 64 (48.4%) patients had an isolated recurrence in the lung, and 16 (25%) patients received local treatment. When comparing patients with isolated lung recurrence, locally treated patients had a longer median progression-free survival than patients treated systemically (41.9 (range, 15.4-NA) vs 7.8 (range, 7.2-10.6) months respectively, p=0.029), a complete response rate of 80% for stereotactic body radiation therapy and a complete resection of 90.9% for surgery. CONCLUSION: Although few patients will benefit from local treatment (stereotactic body radiation therapy or resection) after a recurrence involving the lung, local therapies might be considered as an option in oligometastatic lung recurrences as they achieve high local control rates and better oncological outcomes than systemic treatment alone.


Asunto(s)
Adenocarcinoma , Neoplasias Endometriales , Femenino , Humanos , Estudios Retrospectivos , Proteína p53 Supresora de Tumor , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/terapia , Recurrencia Local de Neoplasia/patología , Pronóstico , Neoplasias Endometriales/genética , Neoplasias Endometriales/terapia , Neoplasias Endometriales/patología , Pulmón/patología , Adenocarcinoma/patología , Estadificación de Neoplasias
2.
Waste Manag Res ; : 734242X231200744, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37791483

RESUMEN

To evaluate the potential of compost based on municipal solid waste (MSW) and 20% legume pruning under a pyrolysis process, generated products, including solids (biochar), liquids (bio-oil), and gases (non-condensable gases), through experimentation in a pilot plant with a fluidized bed reactor at 450°C and gas chromatography/mass spectrometry have been analysed. In addition, the compost kinetic behaviour by thermogravimetric analysis (TGA), using the Flynn-Wall-Ozawa (FWO) method, has been investigated. Four different reaction zones, associated with lignocellulosic materials (hemicellulose, cellulose, and lignin) with a first step for water evaporation, in TGA curve have been observed. A biochar with low stability and aromaticity, considering high and low O/C and H/C ratios, respectively, has been obtained. The obtained pyrolytic liquids contain a high concentration of phenolic compounds because of a significant presence of lignins and other high molecular weight compounds in the original material. Moreover, the generated non-condensable gases consist mainly of short-chain compounds, such as alcohols, aldehydes, and alkenes produced from hemicellulose, cellulose, and proteins.

3.
Rev Clin Esp ; 2020 Jul 15.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32682689

RESUMEN

BACKGROUND AND OBJECTIVES: Osteoporosis is considered a generalised skeletal disorder in which there is impaired bone resistance, which predisposes the individual to a greater risk of fracture. The aim of this cross-sectional study was to collect and present data on the main clinical characteristics of patients who consult medical internists in Spain. Understanding these characteristics can help in implementing action plans to improve these patients' care more effectively and efficiently. MATERIAL AND METHODS: Through an analysis of the Osteoporosis in Internal Medicine (OSTEOMED) registry, this study presents the main clinical characteristics of patients with osteoporosis who attended internal medicine consultations in 23 Spanish hospital centres between 2012 and 2017. We analysed the reasons for the consultations, the densitometric values, the presence of comorbidities, the prescribed treatment and other lifestyle-related factors. RESULTS: In total, 2024 patients with osteoporosis were assessed (89.87% women, 10.13% men). The patients' mean age was 64.1±12.1 years (women, 64.7±11.5 years; men, 61.2±14.2 years). There was no significant difference between the sexes in their history of recent falls (9.1% and 6.7%); however, there were significant differences in the daily intake of calcium from milk products (553.8±332.6mg for women vs. 450.2±303.3mg for men; P<.001) and in the secondary causes of osteoporosis (13% of men vs. 6.5% of women; P<.001). In the sample, there were 404 fractures (20%), with a notable number of confirmed vertebral fractures (17.2%, 35.6% in men vs. 15.2% in women; P<.001). A large portion of the patients did not undergo the indicated treatment and presented low levels of physical activity and sun exposure. A significant percentage of the patients presented associated comorbidities, the most common of which were hypertension (32%) and dyslipidaemia (28%). CONCLUSIONS: These results define the profile of patients with osteoporosis who attend internal medicine consultations in Spain. The results also show the multisystemic character of this condition, which, along with its high prevalence, determine that the specific internal medicine consultations dedicated to managing the condition are the appropriate place for caring for these patients.

4.
J Environ Manage ; 238: 153-158, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30851553

RESUMEN

MSW compost valorization under combustion, at two different composting process conditions, have been studied by thermogravimetric analysis (TGA). The composting operating parameters such as aeration and moisture affect the biodegradability of compost and results of the combustion (different gross heating values for each reactors). The obtained TGA showed that maximum weight loss for 10-12% (245-247 °C), 32-34% (407-411 °C) and 44-46% (760-769 °C) in correspondence to hemicellulose, cellulose and lignin-humic-fulvic acids decomposition for each reactor are observed. Obtained valued in kinetic study (Flynn-Wall-Ozawa method) results in suitable coefficients of determination. In that form, to establish the assumption that combustion of compost under a first-order reaction may be appropriate. Moreover, in both reactors, the conversion rate increased and the activation energy decreased with composting time is found. The maximum gross heating value versus minimum activation energy (for α = 0.25 and α = 0.5) corresponds to final composts and under aeration of 0.050 and 0.175 Lair kg-1 d-1 and moisture of 40% and 55% for R1 and R2 reactors respectively. For MSW, under proper conditions, composting could be used as a suitable biodrying process, stabilizing and concentrating the heating value.


Asunto(s)
Compostaje , Celulosa , Sustancias Húmicas , Lignina , Suelo
5.
J Pathol ; 235(3): 420-30, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25347958

RESUMEN

Intra-uterine growth restriction (IUGR) dramatically increases the risk of bronchopulmonary dysplasia in preterm babies, a disease characterized by arrested alveolarization and abnormal microvascular angiogenesis. We have previously described a rodent low protein diet (LPD) model of IUGR inducing impaired alveolarization, but failed to demonstrate any modification of the classical factors involved in lung development. We performed a genome-wide microarray analysis in 120 rat pups with LPD-induced IUGR and their controls, at three key time points of the alveolarization process: postnatal day 4 (P4): start of alveolarization; P10: peak of the alveolarization process and P21: end of the alveolarization process. Results were analysed using Arraymining, DAVID and KEGG software and validated by qRT-PCR and western blots. Considering a cut-off of 2:1 as significant, 67 transcripts at P4, 102 transcripts at P10 and 451 transcripts at P21 were up-regulated, and 89 transcripts at P4, 25 transcripts at P10 and 585 transcripts at P21 were down-regulated. Automatic functional classification identified three main modified pathways, 'cell adhesion molecules', 'cardiac muscle contraction' and 'peroxisome proliferator-activated receptor' (PPAR). Protein analysis confirmed involvement of the PPAR pathway, with an increase of FABP4, an activator of this pathway, at P4 and an increase of adiponectin at P21. Other data also suggest involvement of the PPAR pathway in impaired alveolarization. Our results show that deregulation of the PPAR pathway may be an important component of the mechanism inducing impaired alveolarization observed in IUGR. The complete dataset is available as GEO profiles on the Gene Expression Omnibus (GEO) database ( www.ncbi.nih.gov/geo/, GEO Accession No. GSE56956).


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Displasia Broncopulmonar/fisiopatología , Retardo del Crecimiento Fetal/fisiopatología , Regulación del Desarrollo de la Expresión Génica/fisiología , Estudio de Asociación del Genoma Completo , Alveolos Pulmonares/crecimiento & desarrollo , Alveolos Pulmonares/fisiopatología , Envejecimiento/fisiología , Animales , Animales Recién Nacidos/fisiología , Displasia Broncopulmonar/etiología , Displasia Broncopulmonar/genética , Moléculas de Adhesión Celular/fisiología , Dieta con Restricción de Proteínas/efectos adversos , Modelos Animales de Enfermedad , Femenino , Retardo del Crecimiento Fetal/genética , Corazón/fisiología , Contracción Muscular/fisiología , Neovascularización Fisiológica/genética , Neovascularización Fisiológica/fisiología , Receptores Activados del Proliferador del Peroxisoma/fisiología , Embarazo , Efectos Tardíos de la Exposición Prenatal/genética , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Alveolos Pulmonares/irrigación sanguínea , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología
6.
BMC Musculoskelet Disord ; 17: 377, 2016 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-27582133

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with an increased risk of osteoporotic fracture. Several factors have been identified as being potentially responsible for this risk, such as alterations in bone remodelling that may have been induced by changes in circulating glucose or/and by the presence of non-oxidative end products of glycosylation (AGEs). The aim of this study is to assess whether such variations generate a change in the gene expression related to the differentiation and osteoblast activity (OPG, RANKL, RUNX2, OSTERIX, and AGE receptor) in primary cultures of human osteoblast-like cells (hOB). METHODS: We recruited 32 patients; 10 patients had osteoporotic hip fractures (OP group), 12 patients had osteoporotic hip fractures with T2DM (T2DM group), and 10 patients had hip osteoarthritis (OA group) with no osteoporotic fractures and no T2DM. The gene expression was analyzed in hOB cultures treated with physiological glucose concentration (4.5 mM) as control, high glucose (25 mM), and high glucose plus AGEs (2 µg/ml) for 24 h. RESULTS: The hOB cultures from patients with hip fractures presented slower proliferation. Additionally, the hOB cultures from the T2DM group were the most negatively affected with respect to RUNX2 and OSX gene expression when treated solely with high glucose or with high glucose plus AGEs. Moreover, high levels of glucose induced a major decrease in the RANKL/OPG ratio when comparing the OP and the T2DM groups to the OA group. CONCLUSIONS: Our data indicates an altered bone remodelling rate in the T2DM group, which may, at least partially, explain the reduced bone strength and increased incidence of non-traumatic fractures in diabetic patients.


Asunto(s)
Remodelación Ósea , Huesos/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fracturas Osteoporóticas/etiología , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Expresión Génica , Glucosa , Productos Finales de Glicación Avanzada , Fracturas de Cadera/metabolismo , Humanos , Masculino , Osteoartritis de la Cadera/metabolismo , Osteoblastos/metabolismo , Fracturas Osteoporóticas/metabolismo , Osteoprotegerina/metabolismo , Cultivo Primario de Células , Ligando RANK/metabolismo , Factor de Transcripción Sp7/metabolismo
7.
Acta Virol ; 60(1): 49-54, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26982467

RESUMEN

Deep sequencing analysis of the transcriptome of a Solanum phureja cv. Criolla Colombia plant with symptoms typical of a virus disease revealed an infection with potato virus V (PVV). The PVV-phureja genome comprises 9904 nt, exhibits 83% nucleotide identity with currently fully sequenced PVV isolates and contains one large ORF that codes for a polyprotein of 3065 residues flanked by 5' and 3' UTR of 217 and 448 nt, respectively. Phylogenetic analysis of the PVV-phureja polyprotein indicates that it is divergent with respect to most PVV isolates. This is the first complete PVV genome of an isolate infecting a host different to S. tuberosum and, to this date, the only one from the South American Andes.


Asunto(s)
Genoma Viral , Enfermedades de las Plantas/virología , Potyvirus/aislamiento & purificación , Solanum/virología , Secuencia de Bases , Colombia , Datos de Secuencia Molecular , Filogenia , Potyvirus/clasificación , Potyvirus/genética
8.
Environ Manage ; 57(6): 1139-52, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26884142

RESUMEN

We explored the capacity of the biological and hydromorphological indices used in the Water Framework Directive (WFD) to assess ecosystem services by evaluating the ecological status of Spanish River Basins. This analysis relies on an exhaustive bibliography review which showed scientific evidence of the interlinkages between some ecosystem services and different hydromorphological and biological elements which have been used as indices in the WFD. Our findings indicate that, of a total of 38 ecosystem services analyzed, biological and hydromorphological indices can fully evaluate four ecosystem services. In addition, 18 ecosystem services can be partly evaluated by some of the analyzed indices, while 11 are not related with the indices. While Riparian Forest Quality was the index that was able to assess the largest number of ecosystem services (N = 12), the two indices of macrophytes offered very poor guarantees. Finally, biological indices related to diatoms and aquatic invertebrates and the Fluvial Habitat Index can be related with 7, 6, and 6 ecosystem services, respectively. Because the WFD indices currently used in Spain are not able to assess most of the ecosystem services analyzed, we suggest that there is potential to develop the second phase of the WFD implementation taking this approach into consideration. The incorporation of the ecosystem services approach into the WFD could provide the framework for assess the impacts of human activities on the quality of fluvial ecosystems and could give insights for water and watershed management in order to guarantee the delivery of multiple ecosystem services.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Monitoreo del Ambiente/métodos , Política Ambiental/legislación & jurisprudencia , Ríos , Animales , Conservación de los Recursos Naturales/legislación & jurisprudencia , Diatomeas/crecimiento & desarrollo , Ecología , Monitoreo del Ambiente/legislación & jurisprudencia , Actividades Humanas , Invertebrados/crecimiento & desarrollo , España , Calidad del Agua
9.
J Dairy Sci ; 98(10): 6651-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26233456

RESUMEN

Conjugated linoleic acid (CLA) has been shown to provide beneficial effects on health; however, the amount consumed in food is far from that required for the desired effects. Thus, increasing the CLA content in dairy foods through milk fermentation with specific lactic acid bacteria (LAB) offers an interesting alternative. Moreover, some LAB may be able to adhere to the intestinal mucosa and produce CLA through endogenous synthesis. Therefore, the objective of this study was to screen LAB isolates for their ability to produce CLA in skim milk and in simulated gastrointestinal conditions. Additionally, the ability of selected CLA-producing LAB to adhere to the intestinal mucosa in a murine model was assessed. Results showed that of 13 strains of Lactobacillus tested, only 4 were able to produce CLA in skim milk supplemented with linoleic acid (13.44 ± 0.78 to 50.9 ± 0.26 µg/mL). Furthermore, these 4 Lactobacillus strains were able to survive and produce CLA in simulated gastrointestinal conditions and to adhere to the intestinal mucosa of Wistar rats after 7 d of oral inoculation with fluorescently labeled bacteria. Accordingly, these 4 Lactobacillus strains may be used to manufacture fermented dairy foods to increase CLA content, and consumption of these fermented milks may result in CLA produced endogenously by these LAB.


Asunto(s)
Intestino Delgado/microbiología , Lactobacillus/fisiología , Ácidos Linoleicos Conjugados/metabolismo , Leche/química , Animales , Adhesión Bacteriana , Productos Lácteos Cultivados/química , Fermentación , Lactobacillus/genética , Masculino , Leche/microbiología , Distribución Aleatoria , Ratas , Ratas Wistar/metabolismo , Ratas Wistar/microbiología
10.
Vet Pathol ; 51(4): 775-86, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24045889

RESUMEN

The ferret has emerged as an excellent animal model to characterize several physiologic and pathologic conditions. The distribution and characterization of different types of immune system cells were studied in healthy ferret tissues. Eight primary antibodies were tested for immunohistochemistry in formalin-fixed tissues: anti-CD3, anti-CD79α, anti-CD20, anti-HLA-DR, anti-lysozyme, anti-CD163, anti-SWC3, and anti-Mac387. The anti-CD3 antibody labeled T cells mainly in interfollicular and paracortical areas of lymph nodes, cortex and thymic medulla, and periarteriolar lymphoid sheaths in the spleen. The anti-CD79α and anti-CD20 antibodies immunolabeled B cells located in lymphoid follicles at lymph nodes, spleen, and Peyer patches. The CD79α and CD20 antibodies also labeled cells with nonlymphoid morphology in atypical B-cell locations. The anti-HLA-DR antibody labeled macrophages, some populations of B and T lymphocytes, and different populations of dendritic cells in lymph nodes, Peyer patches, spleen, and thymus. The anti-lysozyme antibody immunolabeled macrophages in the liver, lymph nodes, spleen, and thymus. The Mac-387, CD163, and SWC3 antibodies did not show any positive reaction in formalin-fixed or frozen tissues. To elucidate the origin of the uncommon CD79α/CD20 positive cells, a double immunohistochemistry was carried out using the anti-HLA-DR + the anti-CD79α, the anti-HLA-DR + the anti-CD20, and the anti-lysozyme + the anti-CD79α antibodies. Double labeling was mainly observed when the anti-HLA-DR + the anti-CD79α antibodies were combined. The immunohistologic characterization and distribution of these immune system cells in healthy ferret tissues should be of value in future comparative studies of diseases in ferrets.


Asunto(s)
Anticuerpos/inmunología , Hurones/inmunología , Sistema Inmunológico/citología , Inmunohistoquímica/veterinaria , Animales , Tejido Linfoide/citología , Masculino , Bazo/citología
11.
Ecotoxicol Environ Saf ; 100: 93-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24238740

RESUMEN

Sea chub, Girella laevifrons, is a coastal fish that inhabits high intertidal rockpools along the coast of Chile. The intertidal pools where the juveniles live, are an extreme environment with high levels of ultraviolet (UV) radiation, becoming harmful to the organisms, due to oxidative stress generated by reactive oxygen species. For this reason organisms develop adaptations that allow them to survive in this complex environment. The search of biomonitor species, sensitive to UV radiation is very important in aquatic ecosystems, mainly in the southern hemisphere where depletion of the ozone layer and the consequent increase of UV radiation, have become an environmental problem. The aim of this study was to evaluate the effect of ultraviolet radiation in G. laevifrons and its possible use as UV-B radiation biomonitor specie in intertidal systems, which are very important for the Chilean fisheries. The effect of UV radiation exposure on juvenile G. laevifrons was measured through oxidative stress parameters. Catalase's activity increased with the time of exposure, unlike superoxide dismutase's activity which peaked at 2h, decreasing towards the 5th hour of irradiation. The superoxide dismutase activity in muscle tissue did not show significant differences. The lipid peroxidation and DNA damage increased in relation to exposition times. Tissue muscle's DNA damage was shown only at 5h of exposure. Significant differences between the two organs in the antioxidant capacity were observed, the liver of G. laevifrons exhibited the higher antioxidant capacity. It can be concluded that this specie exhibits effective protection mechanisms against UV radiation exposure and it is not appropriate specie as a biomonitor in intertidal systems.


Asunto(s)
Ambiente , Peces/fisiología , Estrés Oxidativo/efectos de la radiación , Rayos Ultravioleta , Adaptación Fisiológica/efectos de la radiación , Animales , Antioxidantes/metabolismo , Chile , Daño del ADN/efectos de la radiación , Peces/genética , Peces/metabolismo , Humanos , Peroxidación de Lípido/efectos de la radiación , Oxidación-Reducción , Especies Reactivas de Oxígeno , Temperatura
12.
J Clin Densitom ; 16(1): 87-91, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22980490

RESUMEN

The main aim was to assess whether young and healthy daughters of women with fractures of the distal end of the radius (DER) had less bone mass than the control group. In an observational study of cases and controls (1:1), the daughters of women with fractures of DER (96) were selected at the age of reaching the peak of bone mass and compared with a control group (91). All women underwent medical history, analytical determinations, and densitometry. In the case group, we found lower bone mass values at the spine and femoral neck than the control group. We also found a lower bone mass at the hips of daughters of women with 1 or more osteoporotic fractures associated with DER and at the lumbar spine in those whose mothers had densitometric osteoporosis. In conclusion, young daughters of women with fractures of DER had lower levels of bone mass density, with a possible "location-specific" occurrence based on the presence of 1 or more osteoporotic fractures associated with DER or on the presence of maternal densitometric osteoporosis.


Asunto(s)
Fracturas del Radio/fisiopatología , Absorciometría de Fotón , Adulto , Estudios de Casos y Controles , Niño , Femenino , Cuello Femoral/metabolismo , Humanos , Vértebras Lumbares/metabolismo , Madres , Osteoporosis Posmenopáusica/metabolismo , Fracturas del Radio/genética , Medición de Riesgo , Adulto Joven
13.
J Environ Manage ; 128: 266-73, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23764508

RESUMEN

Composting is one of the most successful biological processes for the treatment of the residues enriched in putrescible materials. The optimization of parameters which have an influence on the stability of the products is necessary in order to maximize recycling and recovery of waste components. The influence of the composting process parameters (aeration, moisture, C/N ratio, and time) on the stability parameters (organic matter, N-losses, chemical oxygen demand, nitrate, biodegradability coefficient) of the compost was studied. The composting experiment was carried out using Municipal Solid Waste (MSW) and Legume Trimming Residues (LTR) in 200 L isolated acrylic barrels following a Box-Behnken central composite experimental design. Second-order polynomial models were found for each of the studied compost stability parameter, which accurately described the relationship between the parameters. The differences among the experimental values and those estimated by using the equations never exceeded 10% of the former. Results of the modelling showed that excluding the time, the C/N ratio is the strongest variable influencing almost all the stability parameters studied in this case, with the exception of N-losses which is strongly dependent on moisture. Moreover, an optimized ratio MSW/LTR of 1/1 (w/w), moisture content in the range of 40-55% and moderate to low aeration rate (0.05-0.175 Lair kg(-)(1) min(-1)) is recommended to maximise degradation and to obtain a stable product during co-composting of MSW and LTR.


Asunto(s)
Fabaceae/metabolismo , Modelos Teóricos , Suelo , Residuos Sólidos , Administración de Residuos/métodos , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Carbono/metabolismo , Nitratos , Nitrógeno/metabolismo
14.
Heliyon ; 9(7): e17943, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37539151

RESUMEN

Leucaena leucocephala is a fast-growing leguminous biomass with great energetical and value-added chemical compounds potential (saccharides, biogas, bio-oil, etc.). Using the thermogravimetric and derivative thermogravimetric curves, the different trends followed by L. leucocephala during pyrolysis, 0.25 equivalence ratio (ER) of gasification, 0.50 equivalence ratio of gasification and combustion were analyzed, and the activation energies were obtained by Distributed Activation Energy Model (DAEM) method. Gas samples were collected through adsorption tubes during the gasification at 0.25 ER and 0.50 ER to observe the distribution of the main chemical products in this process by gas chromatography/mass spectrometry and were compared with pyrolysis products. It was found that small amounts of oxygen have changes in the kinetics of the process, leading to significant decreases in the activation energy at the beginning of the degradation of components such as cellulose (from 170 to 135 kJ mol-1 at 0.25 conversion at 0.50 ER gasification). The activation energy of lignin disintegration was also reduced (342 kJ mol-1), assimilating the beginnings of gasification processes such as the Boudouard reaction. 0.50 ER gasification is potentially an interesting process to obtain quality bio-oil, since a large amount of hexane is detected (44.96%), and value-added oxygenated intermediates such as alcohols and glycols. Gasification at 0.25 ER, on the other hand, is much more similar to pyrolysis, obtaining a wide variety of short-chain compounds resulting from the disintegration of the main lignocellulosic components, especially ketones such as 1-hydroxypropan-2-one (19.48%), and notable amount of furans and anhydrosugars like d-allose (5.50%).

15.
Rev Sci Instrum ; 93(10): 103533, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36319359

RESUMEN

This work presents a novel approach for imaging the visible emissions from plasmas in pulsed power experiments using high-resolution plastic optical fibers. The diagnostic consists of a 2 mm diameter core commercial cable constructed of 13 000 individual acrylic fibers. The fibers are fused together to create a single high-resolution bundle. Different designs were investigated to cover a wide range of resolutions and fields of view (3-700 µm and 0.05-45 mm, respectively). The system was tested on the 1-MA Mykonos accelerator at Sandia National Laboratories and successfully imaged visible emission from a hybrid x-pinch target. Diagnostic development and preliminary results are presented.

16.
Nat Commun ; 13(1): 5568, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36195604

RESUMEN

Plastic degradation by biological systems with re-utilization of the by-products could be a future solution to the global threat of plastic waste accumulation. Here, we report that the saliva of Galleria mellonella larvae (wax worms) is capable of oxidizing and depolymerizing polyethylene (PE), one of the most produced and sturdy polyolefin-derived plastics. This effect is achieved after a few hours' exposure at room temperature under physiological conditions (neutral pH). The wax worm saliva can overcome the bottleneck step in PE biodegradation, namely the initial oxidation step. Within the saliva, we identify two enzymes, belonging to the phenol oxidase family, that can reproduce the same effect. To the best of our knowledge, these enzymes are the first animal enzymes with this capability, opening the way to potential solutions for plastic waste management through bio-recycling/up-cycling.


Asunto(s)
Mariposas Nocturnas , Polietileno , Animales , Biodegradación Ambiental , Monofenol Monooxigenasa/metabolismo , Mariposas Nocturnas/metabolismo , Plásticos/metabolismo , Polietileno/metabolismo , Saliva/metabolismo
17.
Phys Med ; 94: 24-34, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34979431

RESUMEN

PURPOSE: To use MC simulations and phantom measurements to investigate the dosimetry of a kilovoltage x-ray beam from an IR fluoroscope to deliver low-dose (0.3-1.0 Gy) radiotherapy to the lungs. MATERIALS AND METHODS: PENELOPE was used to model a 125 kV, 5.94 mm Al HVL x-ray beam produced by a fluoroscope. The model was validated through depth-dose, in-plane/cross-plane profiles and absorbed dose at 2.5-, 5.1-, 10.2- and 15.2-cm depths against the measured beam in an acrylic phantom. CT images of an anthropomorphic phantom thorax/lungs were used to simulate 0.5 Gy dose distributions for PA, AP/PA, 3-field and 4-field treatments. DVHs were generated to assess the dose to the lungs and nearby organs. Gafchromic film was used to measure doses in the phantom exposed to PA and 4-field treatments, and compared to the MC simulations. RESULTS: Depth-dose and profile results were within 3.2% and 7.8% of the MC data uncertainty, respectively, while dose gamma analysis ranged from 0.7 to 1.0. Mean dose to the lungs were 1.1-, 0.8-, 0.9-, and 0.8- Gy for the PA, AP/PA, 3-field, and 4-field after isodose normalization to cover âˆ¼ 95% of each lung volume. Skin dose toxicity was highest for the PA and lowest for the 4-field, and both arrangements successfully delivered the treatment on the phantom. However, the dose distribution for the PA was highly non-uniform and produced skin doses up to 4 Gy. The dose distribution for the 4-field produced a uniform 0.6 Gy dose throughout the lungs, with a maximum dose of 0.73 Gy. The average percent difference between experimental and Monte Carlo values were -0.1% (range -3% to +4%) for the PA treatment and 0.3% (range -10.3% to +15.2%) for the 4-field treatment. CONCLUSION: A 125 kV x-ray beam from an IR fluoroscope delivered through two or more fields can deliver an effective low-dose radiotherapy treatment to the lungs. The 4-field arrangement not only provides an effective treatment, but also significant dose sparing to healthy organs, including skin, compared to the PA treatment. Use of fluoroscopy appears to be a viable alternative to megavoltage radiation therapy equipment for delivering low-dose radiotherapy to the lungs.


Asunto(s)
Radiología Intervencionista , Radiometría , Fluoroscopía , Pulmón/diagnóstico por imagen , Método de Montecarlo , Fantasmas de Imagen , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
18.
Water Res ; 221: 118727, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35797818

RESUMEN

Hypersaline endorheic aquatic systems (H-SEAS) are lakes/shallow playas in arid and semiarid regions that undergo extreme oscillations in salinity and severe drought episodes. Although their geochemical uniqueness and microbiome have been deeply studied, very little is known about the availability and quality of dissolved organic matter (DOM) in the water column.. A H-SEAS from the Monegros Desert (Zaragoza, NE Spain) was studied during a hydrological wetting-drying-rewetting cycle. DOM analysis included: (i) a dissolved organic carbon (DOC) mass balance; (ii) spectroscopy (absorbance and fluorescence) and (iii) a molecular characterization with Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The studied system stored a large amount of DOC and under the highest salinity conditions, salt-saturated waters (i.e., brines with salinity > 30%) accumulated a disproportionate quantity of DOC, indicating a significant in-situ net DOM production. Simultaneously, during the hydrological transition from wet to dry, the DOM pool showed strong alterations of it molecular composition. Spectroscopic methods indicated that aromatic and degraded DOM was rapidly replaced by fresher, relatively small, microbial-derived moieties with a large C/N ratio. FT-ICR-MS highlighted the accumulation of small, saturated and oxidized molecules (molecular O/C > 0.5), with a remarkable increase in the relative contribution of highly oxygenated (molecular O/C>0.9) compounds and a decrease of aliphatic and carboxyl-rich alicyclic moleculesThese results indicated that H-SEAS are extremely active in accumulating and processing DOM, with the notable release of organic solutes probably originated from decaying microplankton under large osmotic stress at extremely high salinities.


Asunto(s)
Materia Orgánica Disuelta , Lagos , Hidrología , Lagos/química , Espectrometría de Masas , Agua
19.
Biomed Phys Eng Express ; 8(6)2022 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-35961284

RESUMEN

Objective.The goal of this study was to use Monte Carlo (MC) simulations and measurements to investigate the dosimetric suitability of an interventional radiology (IR) c-arm fluoroscope to deliver low-dose radiotherapy to the lungs.Approach.A previously-validated MC model of an IR fluoroscope was used to calculate the dose distributions in a COVID-19-infected patient, 20 non-infected patients of varying sizes, and a postmortem subject. Dose distributions for PA, AP/PA, 3-field and 4-field treatments irradiating 95% of the lungs to a 0.5 Gy dose were calculated. An algorithm was created to calculate skin entrance dose as a function of patient thickness for treatment planning purposes. Treatments were experimentally validated in a postmortem subject by using implanted dosimeters to capture organ doses.Main results.Mean doses to the left/right lungs for the COVID-19 CT data were 1.2/1.3 Gy, 0.8/0.9 Gy, 0.8/0.8 Gy and 0.6/0.6 Gy for the PA, AP/PA, 3-field, and 4-field configurations, respectively. Skin dose toxicity was the highest probability for the PA and lowest for the 4-field configuration. Dose to the heart slightly exceeded the ICRP tolerance; all other organ doses were below published tolerances. The AP/PA configuration provided the best fit for entrance skin dose as a function of patient thickness (R2 = 0.8). The average dose difference between simulation and measurement in the postmortem subject was 5%.Significance.An IR fluoroscope should be capable of delivering low-dose radiotherapy to the lungs with tolerable collateral dose to nearby organs.


Asunto(s)
COVID-19 , Planificación de la Radioterapia Asistida por Computador , COVID-19/radioterapia , Humanos , Pulmón/diagnóstico por imagen , Método de Montecarlo , Radiología Intervencionista , Planificación de la Radioterapia Asistida por Computador/métodos
20.
Injury ; 52 Suppl 4: S145-S150, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33750586

RESUMEN

PURPOSE: Evaluate the Scratch Collapse Test in an objective way, by replacing the subjective evaluation made by the physician with an objective evaluation measure, made with a digital dynamometer. METHODS: Observational study carried out, in 90 patients divided into three groups of 30 patients, taking into account the electromyographic study of the median nerve in the carpal tunnel (no alteration, moderate, severe).The external rotation of the shoulder was measured in four different situations (no scratch, scratch over the carpal tunnel, scratch in the dorsum of the wrist and scratch in the shoulder). RESULTS: There were no statistical differences in the result of the strength in any of the four different situations in patients without carpal tunnel of with moderate carpal tunnel syndrome. However, there were statistical differences between the basal measurement (without scratching) and the measurement after tunnel scratching in patients with severe carpal tunnel syndrome. But this statistical difference was only 0.08 kg in the average measure, and this difference is clinically undetectable and far for producing a real collapse of the external rotation of the shoulder. CONCLUSION: The Scratch Collapse Test is not a valid diagnostic exam for carpal tunnel syndrome if the strength is measured in an objective manner.


Asunto(s)
Síndrome del Túnel Carpiano , Síndrome del Túnel Carpiano/diagnóstico , Humanos , Nervio Mediano , Articulación de la Muñeca
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