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1.
Int J Mol Sci ; 23(23)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36499256

RESUMEN

Boron neutron capture therapy (BNCT) is a re-emerging technique for selectively killing tumor cells. Briefly, the mechanism can be described as follows: after the uptake of boron into cells, the thermal neutrons trigger the fission of the boron atoms, releasing the α-particles and recoiling lithium particles and high-energy photons that damage the cells. We performed a detailed study of the reactor dosimetry, cellular dose assessment, and radiobiological effects induced by BNCT in glioblastoma (GBM) cells. At maximum reactor power, neutron fluence rates were ϕ0 = 6.6 × 107 cm−2 s−1 (thermal) and θ = 2.4 × 104 cm−2 s−1 with a photon dose rate of 150 mGy·h−1. These values agreed with simulations to within 85% (thermal neutrons), 78% (epithermal neutrons), and 95% (photons), thereby validating the MCNPX model. The GEANT4 simulations, based on a realistic cell model and measured boron concentrations, showed that >95% of the dose in cells was due to the BNC reaction. Carboranylmethylbenzo[b]acridone (CMBA) is among the different proposed boron delivery agents that has shown promising properties due to its lower toxicity and important cellular uptake in U87 glioblastoma cells. In particular, the results obtained for CBMA reinforce radiobiological effects demonstrating that damage is mostly induced by the incorporated boron with negligible contribution from the culture medium and adjacent cells, evidencing extranuclear cell radiosensitivity.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Glioblastoma , Humanos , Terapia por Captura de Neutrón de Boro/métodos , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Glioblastoma/patología , Neutrones , Boro , Fotones
2.
Reproduction ; 162(4): R55-R71, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34338216

RESUMEN

Immune infertility occurs due to the presence of antisperm antibodies (ASA). This type of infertility has a relatively low prevalence (2.6-6.6% in infertile men), and its etiology, risk factors, targets, and consequences for male fertility are not completely understood. While it is largely accepted that abnormalities in the blood-testis barrier and/or blood-epididymal barrier are the main factors behind its etiology, and that sperm motility is the most frequently reported altered parameter, few are the well-defined risk factors and ASA targets only now started to be disclosed, with proteins involved in sperm-oocyte interaction rising as the most significant. The development of potential treatments is also limited, being the corticosteroids the more promising. Overall, there are still many knowledge gaps related to immune infertility. With this review, we aimed to gather all the information collected from studies developed in humans in the last decade. Despite the controversial results/inconsistencies, that are not only a result of the complexity of mechanisms/variables involved in ASA infertility but also from the technical approaches to assess ASA and the lack of a consensus regarding the thresholds to be used, this manuscript aims to bring a fresh update on the field. It has become clear that, to obtain more/reliable data, there is a need to assess ASA in all the routine seminal analyses, following WHO recommendations. In this way, it will be possible to obtain consistent and comparable information, that can add to current knowledge. Additionally, multicentric studies with large cohorts are also missing, and future research should take this into consideration.


Asunto(s)
Infertilidad Masculina , Motilidad Espermática , Anticuerpos/análisis , Anticuerpos/metabolismo , Autoanticuerpos , Epidídimo , Humanos , Infertilidad Masculina/etiología , Infertilidad Masculina/metabolismo , Masculino , Espermatozoides/metabolismo
3.
Eur J Contracept Reprod Health Care ; 26(4): 334-342, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33821738

RESUMEN

BACKGROUND: Spermicides have been identified as a potentially attractive alternative to hormonal contraceptives and/or intrauterine devices. Thus, this study aimed evaluating the efficacy and local tolerance of benzalkonium chloride (BKC) and myristalkonium chloride (MKC) contained in Pharmatex® vaginal formulations and compare them with nonoxynol-9 (N-9), the most common active ingredient in topical vaginal contraceptives. METHODS: Human normozoospermic samples were assessed for motility, viability, acrosome status and penetration ability after exposure to control, N-9 or different BKC and MKC doses for 0 and 10 minutes. Local tolerance on HeLa cells was evaluated by the Trypan-blue and MTT assays. RESULTS: Exposure to BKC and MKC reduced acrosome integrity while promoting total immobilisation and complete loss of sperm viability (p < .001, n = 15). Both compounds also compromised sperm penetration ability upon exposure (p < .001, n = 15). N-9 induced the same outcomes (p < .001, n = 15); nevertheless, it was more toxic to HeLa cells than BKC and MKC (p < .05, n = 14). CONCLUSIONS: BKC and MKC present strong in vitro spermicidal activity at lower doses than N-9 and were better tolerated after immediate exposure than N-9. Available Pharmatex® galenic formulations were as effective as products based on N-9.


Asunto(s)
Compuestos de Benzalconio/farmacología , Anticonceptivos/farmacología , Nonoxinol/farmacología , Espermicidas/farmacología , Espermatozoides/efectos de los fármacos , Cloruros , Femenino , Células HeLa/efectos de los fármacos , Humanos , Masculino
4.
Membranes (Basel) ; 11(1)2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33374743

RESUMEN

Broad-spectrum fluoroquinolone antibiotics (ciprofloxacin and levofloxacin), carbapenem and fluoroquinolone resistance genes, as well as viral genomes, were detected in grab samples of wastewater effluents. Passive samplers, which are simpler and easier to use and provide information about the concentrations and combination of contaminants present in a certain fluid matrix over time, proved to be extremely promising devices to monitor the presence of the target antibiotics in wastewater effluents. Nanofiltration was tested with a pilot-scale unit installed at a domestic wastewater treatment facility, using a Desal 5DK membrane operated at a constant transmembrane pressure of 6 bar and 70% recovery rate. In a 24 h experimental assay, the variation of the membrane permeance was low (6.3%). High rejections of the target contaminants from the wastewater effluent were obtained by the pilot-scale treatment. Hence, nanofiltration using the Desal 5DK membrane is considered to be a promising treatment to cope with chemical and biological contaminants present in wastewater effluents.

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