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1.
Heliyon ; 10(5): e26597, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38434285

RESUMEN

The generation of power and fuel sustainability that contributes to a cleaner output of exhaust gases is one of the most important objectives the world seeks. In this paper, oxyhydrogen gas is used to retrofit into a two-stroke engine. The water was electrolysed and generated a mixture of oxygen (O2) and hydrogen (H2) or known as oxyhydrogen (HHO) gas via an electrolytic dry cell generator. The HHO was retrofitted experimentally to investigate the engine emissions and exhaust gas temperature from a 1.5 kW gasoline engine. The engine was tested with different power ratings (84-720 W) to investigate the performance and emissions of the engine using gasoline followed by the addition of HHO. The emissions of CO and NOx were measured with different amounts of HHO added. The exhaust temperature was calculated as one of the variables to be considered in relation to pollution. The air-fuel ratios are varied from 12 to 20% in the experiment. The most appropriate air-fuel ratio needed to start the generator with the most environmentally friendly gas emission was analysed. The results showed that the addition of HHO to the engine is successful in reducing fuel consumption up to 8.9%. A higher percentage of HHO added also has improved the emissions and reduced exhaust gas temperature. In this study, the highest quantity of HHO added at 0.15% of the volume fraction reduced CO gas emission by up to 9.41%, NOx gas up to 4.31%, and exhaust gas temperature by up to 2.02%. Generally, adding oxyhydrogen gas has significantly reduced the emissions, and exhaust temperature and provided an eco-friendly environment.

2.
Sci Rep ; 13(1): 17144, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37816781

RESUMEN

Metastatic castration resistant prostate cancer (mCRPC) is still the lethal stage for the whole spectrum of prostate cancer disease. Even though different treatment options have been introduced in the last decade with a significant survival improvement for this population, a lack of more reliable prognostic and predictive markers is still one of the main clinical challenges in management of mCRPC. The aim of this study was to investigate the correlation between Natural Killer cell activity (NKA) and both treatment effect and outcomes in patients with mCRPC treated with enzalutamide. A total of 87 patients with mCRPC treated with enzalutamide as the first line treatment were enrolled. NKA was estimated at baseline and prior to each treatment cycle. Endpoints included both treatment effect with biochemical response (BR), biochemical progression (BP) and radiological progression (RP), as well as outcome data with overall survival (OS), radiologic progression free survival (rPFS), and time to next treatment (TTT). At the time of BR, interferon-gamma (IFNγ) decreased significantly compared to levels detected at baseline (z-score = 2.33, p = 0.019). Regarding outcome data, the whole cohort was divided into four groups according to the change of IFNγ level during the first 3 cycles of enzalutamide treatment. In group 1 (n = 42) the IFNγ level remained within a normal range (≥ 250 pg/mL),while in group 2 (n = 7) it increased from an abnormal (< 250 pg/mL) to a normal level. In group 3 (n = 13) it dropped to an abnormal level, and it remained at an abnormal level during treatment in group 4 (n = 17). Patients in group 2 showed the worst prognosis with shorter both rPFS and TTT (HR 4.30, p = 0.037; and HR 6.82, p = 0.011, respectively). In this study inverse correlations between NKA and both treatment response and outcomes was observed in mCRPC patients receiving enzalutamide, suggesting an unfavourable role of NK cells in the late stage of PCa.


Asunto(s)
Antineoplásicos , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Neoplasias de la Próstata Resistentes a la Castración/patología , Antineoplásicos/uso terapéutico , Antígeno Prostático Específico , Nitrilos/uso terapéutico , Células Asesinas Naturales/patología , Resultado del Tratamiento
3.
Micromachines (Basel) ; 13(6)2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35744488

RESUMEN

Despite the recycling challenges in ionic fluids, they have a significant advantage over traditional solvents. Ionic liquids make it easier to separate the end product and recycle old catalysts, particularly when the reaction media is a two-phase system. In the current analysis, the properties of transient, electroviscous, ternary hybrid nanofluid flow through squeezing parallel infinite plates is reported. The ternary hybrid nanofluid is synthesized by dissolving the titanium dioxide (TiO2), aluminum oxide (Al2O3), and silicon dioxide (SiO2) nanoparticles in the carrier fluid glycol/water. The purpose of the current study is to maximize the energy and mass transfer rate for industrial and engineering applications. The phenomena of fluid flow is studied, with the additional effects of the magnetic field, heat absorption/generation, chemical reaction, and activation energy. The ternary hybrid nanofluid flow is modeled in the form of a system of partial differential equations, which are subsequently simplified to a set of ordinary differential equations through resemblance substitution. The obtained nonlinear set of dimensionless ordinary differential equations is further solved, via the parametric continuation method. For validity purposes, the outcomes are statistically compared to an existing study. The results are physically illustrated through figures and tables. It is noticed that the mass transfer rate accelerates with the rising values of Lewis number, activation energy, and chemical reaction. The velocity and energy transfer rate boost the addition of ternary NPs to the base fluid.

4.
Sci Rep ; 10(1): 227, 2020 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-31937854

RESUMEN

Metastatic castration resistant prostate cancer (mCRPC) is associated with high mortality, where monitoring of disease activity is still a major clinical challenge. The role of microRNAs (miRs) has been widely investigated in prostate cancer with both diagnostic and prognostic potential. The aim of this study was to investigate the relationship between circulating miRs and treatment outcome in mCRPC patients. The relative expression of five miRs (miR-93-5p, -125b-1-5p, -141-3p, -221-3p, and miR-375-3p) was investigated in plasma samples from 84 mCRPC patients; 40 patients were treated with docetaxel (DOC cohort) and 44 patients with abiraterone (ABI cohort). Blood was sampled at baseline before treatment start and at radiological progression. The plasma levels of four miRs; miR-93-5p, -141-3p, -221-3p, and miR-375-3p decreased significantly after treatment initiation in patients receiving docetaxel, and for miR-141-3p and miR-375-3p the level increased again at the time of radiological progression. In the patients treated with abiraterone, the plasma level of miR-221-3p likewise decreased significantly after the first treatment cycle. High baseline levels of both miR-141-3p and miR-375-3p were significantly associated with a shorter time to radiological progression in both cohorts. Additionally, high baseline levels of miR-141-3p and miR-221-3p were significantly associated with a shorter overall survival (OS) in the ABI cohort, while high levels of miR-141-3p and miR-375-3p were significantly associated with shorter OS in the DOC cohort. Plasma levels of miR-141-3p and miR-375-3p may predict time to progression in mCRPC patients treated with docetaxel or abiraterone. The clinical impact of these findings is dependent on validation in larger cohorts.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/sangre , MicroARN Circulante/análisis , MicroARNs/sangre , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Androstenos/administración & dosificación , Estudios de Casos y Controles , Docetaxel/administración & dosificación , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Estudios Prospectivos , Neoplasias de la Próstata Resistentes a la Castración/sangre , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patología , Tasa de Supervivencia
5.
Cardiovasc Eng Technol ; 10(1): 95-111, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30488177

RESUMEN

PURPOSE: Peristaltic pumps (PP) are favored in flow bioreactors for their non-contact sterile design. But they produce pulsatile flow, which is consequential for the cultured cells. A novel pulse damper (PD) is reported for pulsatility elimination. METHODS: The PD design was implemented to target static pressure pulsatility and flow rate (velocity) pulsatility from a PP. Damping effectiveness was tested in a macro-scale, closed-loop recirculating bioreactor mimicking the aortic arch at flow rates up to (4 L/min). Time-resolved particle image velocimetry was used to characterize the velocity field. Endothelial cells (EC) were grown in the bioreactor, and subjected to continuous flow for 15 min with or without PD. RESULTS: The PD was found to be nearly 90% effective at reducing pulsatility. The EC exposed to low PP flow without PD exhibited distress signaling in the form of increased ERK1/2 phosphorylation (2.5 folds) when compared to those exposed to the same flow with PD. At high pump flow without PD, the cells detached and did not survive, while they were perfectly healthy with PD. CONCLUSIONS: Flow pulsatility from PP causes EC distress at low flow and cell detachment at high flow. Elevated temporal shear stress gradient combined with elevated shear stress magnitude at high flow are believed to be the cause of cell detachment and death. The proposed PD design was effective at minimizing the hemodynamic stressors in the pump's output, demonstrably reducing cell distress. Adoption of the proposed PD design in flow bioreactors should improve experimental protocols.


Asunto(s)
Reactores Biológicos , Técnicas de Cultivo de Célula/instrumentación , Células Endoteliales de la Vena Umbilical Humana/fisiología , Flujo Pulsátil , Adhesión Celular , Supervivencia Celular , Células Cultivadas , Diseño de Equipo , Quinasas MAP Reguladas por Señal Extracelular , Humanos , Mecanotransducción Celular , Fosforilación , Presión , Estrés Mecánico , Factores de Tiempo
6.
J R Soc Interface ; 12(108): 20150252, 2015 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-26063819

RESUMEN

Three-dimensional imaging of human stem cells using transmission soft X-ray tomography (SXT) is presented for the first time. Major organelle types--nuclei, nucleoli, mitochondria, lysosomes and vesicles--were discriminated at approximately 50 nm spatial resolution without the use of contrast agents, on the basis of measured linear X-ray absorption coefficients and comparison of the size and shape of structures to transmission electron microscopy (TEM) images. In addition, SXT was used to visualize the distribution of a cell surface protein using gold-labelled antibody staining. We present the strengths of SXT, which include excellent spatial resolution (intermediate between that of TEM and light microscopy), the lack of the requirement for fixative or contrast agent that might perturb cellular morphology or produce imaging artefacts, and the ability to produce three-dimensional images of cells without microtome sectioning. Possible applications to studying the differentiation of human stem cells are discussed.


Asunto(s)
Nucléolo Celular/ultraestructura , Tomografía con Microscopio Electrónico , Imagenología Tridimensional , Lisosomas/ultraestructura , Mitocondrias/ultraestructura , Células Madre/ultraestructura , Tomografía por Rayos X , Anticuerpos/química , Oro/química , Humanos , Coloración y Etiquetado
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