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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124681, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38905898

RESUMEN

This study investigates the immobilization mechanisms of heavy metal ions in the C-S-H phase. Synthetic C-S-H phases were prepared via the precipitation method, incorporating five different ions (Pb(II), Cd(II), Ni(II), Zn(II), and Cr(III)). Structural analysis of the obtained material was conducted using vibrational spectroscopy (both FT-IR and Raman), X-ray photoelectron spectroscopy, and X-ray diffraction. Spectroscopic methods were primarily employed to evaluate the structural effects and polymerization degree of the resulting C-S-H phase. Morphological changes were characterized using scanning and transmission electron microscopy (SEM and TEM, respectively). Our findings reveal several mechanisms for immobilizing heavy metal cations: precipitation of insoluble compounds (particularly notable for Ni(II) and Cr(III)), replacement of Ca(II) ions within the silicate structure (evident in the crystallization of Ca(OH)2 in samples containing Cd(II), Ni(II), and Zn(II) in minimal quantities), and strong bonding of certain metals (such as Pb(II)) with the C-S-H phase structure. These insights contribute to understanding the potential applications of C-S-H phases in heavy metal immobilization.

2.
J Contam Hydrol ; 264: 104341, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38701693

RESUMEN

Canada's deep geological repository (DGR) design includes an engineered barrier system where highly compacted bentonite (HCB) surrounds the copper-coated used fuel containers (UFCs). Microbial-influenced corrosion is a potential threat to long-term integrity of UFC as bisulfide (HS-) may be produced by microbial activities under anaerobic conditions and transported via diffusion through the HCB to reach the UFC surface, resulting in corrosion of copper. Therefore, understanding HS- transport mechanisms through HCB is critical for accurate prediction of copper corrosion allowance. This study investigated HS- transport behaviour through MX-80 bentonite at dry densities 1070-1615 kg m-3 by performing through-diffusion experiments. Following HS- diffusion, bromide (Br-) diffusion and Raman spectroscopy analyses were performed to explore possible physical or mineralogical alterations of bentonite caused by interacting with HS-. In addition, accessible porosity ε was estimated using extended Archie's law. Effective diffusion coefficient of HS- was found 2.5 × 10-12 m2 s-1 and 5.0× 10-12 m2 s-1 for dry densities 1330 and 1070 kg m-3, respectively. No HS- breakthrough was observed for highly compacted bentonite (1535-1615 kg m-3) over the experimental timeframe (170 days). Raman spectroscopy results revealed that HS- reacted with iron in bentonite and precipitated as mackinawite and, therefore, it was immobilized. Finally, results of this study imply that HS- transport towards UFC will be highly controlled by the available iron content and dry density of the buffer material.


Asunto(s)
Bentonita , Sulfuros , Bentonita/química , Difusión , Sulfuros/química , Sulfuros/metabolismo , Espectrometría Raman , Cobre/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo
3.
J Physiol Pharmacol ; 74(3)2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37661178

RESUMEN

Glioblastoma, the most common and aggressive type of brain tumor in adults, poses significant challenges in terms of treatment. Conventional approaches including surgery, chemotherapy, and radiotherapy have yielded limited success, with a median survival of approximately 15 months. However, extensive research into the biology of glioblastoma has identified molecular targets that can be exploited by newly developed drugs, leading to the emergence of precise personalized therapies. Several innovative treatment strategies are currently under development, aiming to enhance effectiveness while minimizing side effects. Clinical trials are underway to evaluate the efficacy of monoclonal antibodies that target glioblastoma cells, either by blocking specific receptors or by modifying molecular interactions that impede cell proliferation. Another promising avenue involves the use of oncolytic viruses designed to selectively infect glioblastoma cells. Additionally, the review explores the utilization of nanocarriers capable of surmounting the formidable obstacle of the blood-brain barrier, enabling efficient drug delivery. Cell therapies represent another promising approach, with dendritic cells, chimeric antigen receptor-T cells, and macrophages emerging as potential treatment modalities. By summarizing recent advances in targeted therapies against glioblastoma, this review aims to provide a comprehensive overview of ongoing efforts to discover effective and safe methods for treating glioblastoma patients. The ultimate goal is to improve patient outcomes and transform the landscape of glioblastoma treatment.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Glioblastoma/tratamiento farmacológico , Barrera Hematoencefálica , Neoplasias Encefálicas/tratamiento farmacológico , Proliferación Celular , Tratamiento Basado en Trasplante de Células y Tejidos
4.
BMC Pulm Med ; 23(1): 218, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37340431

RESUMEN

PURPOSE: Real-world data on antibiotic management of nontuberculous mycobacterial lung disease (NTM-LD) is limited for many countries. This study aimed to evaluate real-world treatment practices of NTM-LD in the Netherlands using medication dispensing data. METHODS: A retrospective longitudinal real-world study was conducted using IQVIA's Dutch pharmaceutical dispensing database. The data are collected monthly and include approximately 70% of all outpatient prescriptions in the Netherlands. Patients initiated on specific NTM-LD treatment regimens between October 2015 and September 2020 were included. The main areas of investigation were initial treatment regimens, persistence on treatment, treatment switching, treatment compliance in terms of medication possession rate (MPR) and restarts of treatment. RESULTS: The database included 465 unique patients initiated on triple- or dual-drug regimens for the treatment of NTM-LD. Treatment switches were common and occurred approximately 1.6 per quarter throughout the treatment period. The average MPR of patients initiated on triple-drug therapy was 90%. The median time on therapy for these patients was 119 days; after six months and one year, 47% and 20% of the patients, respectively, were still on antibiotic therapy. Of 187 patients initiated on triple-drug therapy, 33 (18%) patients restarted antibiotic therapy after the initial treatment had been stopped. CONCLUSION: When on therapy, patients were compliant with the NTM-LD treatment; however, many patients stopped their therapy prematurely, treatment switches often occurred, and part of patients had to restart their therapy after a longer treatment gap. NTM-LD management should be improved through greater guideline adherence and appropriate involvement of expert centers.


Asunto(s)
Enfermedades Pulmonares , Infecciones por Mycobacterium no Tuberculosas , Neumonía , Humanos , Estudios Retrospectivos , Países Bajos , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/microbiología , Antibacterianos/uso terapéutico , Micobacterias no Tuberculosas , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/epidemiología , Enfermedades Pulmonares/microbiología
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 294: 122559, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36870181

RESUMEN

Calcium aluminosilicate hydrates (C-(A)-S-H) with two different C/S molar ratios of 1.0 and 1.7 were synthesized by precipitation with the use of the alkali-activation method. The samples were synthesized with solutions of heavy metals nitrates such as nickel (Ni), chromium (Cr), cobalt (Co), lead (Pb), and zinc (Zn). Metal cations were added in the amount of Ca:Me equal to 9:1, while Al/Si was 0.05. The influence of the addition of heavy metal cations on the structure of the C-(A-)S-H phase was investigated. For this purpose, XRD was used to examine the phase composition of the samples, FT-IR and Raman spectroscopy were used to determine the effect of heavy metal cations on the structure of the obtained C-(A)-S-H phase and their degree of polymerization. Using SEM and TEM, changes in the morphology of the obtained materials were determined. Possible mechanisms of immobilization of heavy metal cations have been determined. It was found that some heavy metals (Ni, Zn, and Cr) could be immobilized by precipitation of insoluble compounds. On the other hand, they could remove Ca2+ ions from the structure of aluminosilicate and take their place, as evidenced by the crystallization of Ca(OH)2 in samples with the addition of Cd, but also Ni and Zn in small amounts. A third possibility is the incorporation of heavy metal cations at the silicon and/or aluminum tetrahedral sites, as is the case with Zn.

6.
Nat Commun ; 13(1): 5340, 2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-36096889

RESUMEN

Topological physics relies on Hamiltonian's eigenstate singularities carrying topological charges, such as Dirac points, and - in non-Hermitian systems - exceptional points (EPs), lines or surfaces. So far, the reported non-Hermitian topological transitions were related to the creation of a pair of EPs connected by a Fermi arc out of a single Dirac point by increasing non-Hermiticity. Such EPs can annihilate by reducing non-Hermiticity. Here, we demonstrate experimentally that an increase of non-Hermiticity can lead to the annihilation of EPs issued from different Dirac points (valleys). The studied platform is a liquid crystal microcavity with voltage-controlled birefringence and TE-TM photonic spin-orbit-coupling. Non-Hermiticity is provided by polarization-dependent losses. By increasing the non-Hermiticity degree, we control the position of the EPs. After the intervalley annihilation, the system becomes free of any band singularity. Our results open the field of non-Hermitian valley-physics and illustrate connections between Hermitian topology and non-Hermitian phase transitions.

7.
Br J Dermatol ; 184(3): 464-472, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32510578

RESUMEN

BACKGROUND: Although solely topical treatment often suffices, patients with psoriasis may require more intensive treatment (phototherapy and/or systemic treatments) to control their disease. However, in paediatric, adolescent and young adult patients, little is known about persistence of topical treatment and time until switch to systemic treatment. OBJECTIVES: To determine the median time from psoriasis onset until (i) discontinuation of solely topical agents and (ii) switch to systemic treatment, and to identify patient characteristics associated with switching to systemic treatments. METHODS: Data were extracted from the Child-CAPTURE registry, a prospective, observational cohort of patients with paediatric-onset psoriasis followed into young adulthood from 2008 to 2018. Data prior to inclusion in the registry were collected retrospectively. Median times were determined through Kaplan-Meier survival analyses. Cox regression analysis was used to identify patient characteristics associated with switch to systemic treatment. RESULTS: Of 448 patients, 62·3% stayed on solely topical treatment until data lock; 14·3% switched from topicals to phototherapy, but not to systemic treatment; and 23·4% switched to systemic treatment. The median time from psoriasis onset until discontinuation of solely topical treatment was 7·3 years, and until switch to systemics was 10·8 years. Higher Psoriasis Area and Severity Index and (Children's) Dermatology Life Quality Index > 5 were independently associated with switching to systemic treatment. CONCLUSIONS: In a population of paediatric and adolescent patients with mild-to-severe psoriasis, one-third needed more intensive treatment than solely topical therapy to control their disease. We consider the median time until switching to systemics to be long.


Asunto(s)
Fármacos Dermatológicos , Psoriasis , Adolescente , Adulto , Niño , Estudios de Cohortes , Fármacos Dermatológicos/uso terapéutico , Humanos , Estudios Prospectivos , Psoriasis/tratamiento farmacológico , Estudios Retrospectivos , Adulto Joven
8.
Sci Rep ; 9(1): 20033, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31882705

RESUMEN

Nitrogen dioxide (NO2) is a regulated air pollutant that is of particular concern in many cities, where concentrations are high. Emissions of nitrogen oxides to the atmosphere lead to the formation of ozone and particulate matter, with adverse impacts on human health and ecosystems. The effects of emissions are often assessed through modeling based on inventories relying on indirect information that is often outdated or incomplete. Here we show that NO2 measurements from the new, high-resolution TROPOMI satellite sensor can directly determine the strength and distribution of emissions from Paris. From the observed build-up of NO2 pollution, we find highest emissions on cold weekdays in February 2018, and lowest emissions on warm weekend days in spring 2018. The new measurements provide information on the spatio-temporal distribution of emissions within a large city, and suggest that Paris emissions in 2018 are only 5-15% below inventory estimates for 2011-2012, reflecting the difficulty of meeting NOx emission reduction targets.

9.
J Physiol Pharmacol ; 70(5)2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31889039

RESUMEN

Currently, many therapies fail due to an insufficient drug dose reaching the target site and high systemic toxicity. Protein-based drug delivery systems that allow an increase in drug concentration at a specific location in the body or predominantly target malignant cells are promising technologies. Due to the high need for iron in many disorders including various types of cancer, iron-binding proteins: transferrin, ferritin and hemoglobin, are a promising tool as drug carriers. In this review we summarize the characteristics of human iron-binding proteins and present their use in targeted drug delivery strategies.


Asunto(s)
Proteínas de Unión a Hierro/metabolismo , Hierro/metabolismo , Animales , Portadores de Fármacos/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo
10.
Transplant Proc ; 50(7): 2202-2211, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30177137

RESUMEN

BACKGROUND: High-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (auto-PBSCT) remains the mainstay of treatment of eligible patients diagnosed multiple myeloma. The role of clonal plasma cell (CPC) contamination was found as a reason for relapse, but results in terms of survival, progression, and purging were ambiguous. Therefore, the aim of the study was to explore the influence of CPC contamination in the autograft on survival and progression after auto-PBSCT. STUDY DESIGN: The study included 59 patients diagnosed and treated for multiple myeloma in 1998-2004. Cells with coexpression of CD38+++CD138++CD56+ and lacking the expression of CD45, CD19, CD10, CD20, and CD23 were considered CPC in flow cytometry. RESULTS: The risk of death and progression after auto-PBSCT increased significantly by 10% (P < .021) and 8% (P < .034) per 1 × 106/kg of the CPC number, respectively. For CPC number above 2.96 × 106/kg overall survival achieved clinical significance. Two years after auto-PBSCT, the risk of death was independent of CPC number among the patients who survived (P = .70). Analogous conclusions concerned results of progression-free survival at 1 year after auto-PBSCT. CONCLUSIONS: High clonal plasma cell contamination (>2.96 ×1 06/kg; 90th percentile of CPC number) is associated with the worst progression-free survival and overall survival. Therefore purging in vitro might be considered for the patients with the highest CPC contamination. Negative consequences of CPC contamination on the risk of death are observed for only 2 years after auto-PBSCT. Thereafter only those patients who had lower CPC contamination survived.


Asunto(s)
Autoinjertos/patología , Mieloma Múltiple/terapia , Trasplante de Células Madre de Sangre Periférica/mortalidad , Células Madre de Sangre Periférica/patología , Células Plasmáticas/patología , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Recurrencia Local de Neoplasia/etiología , Trasplante de Células Madre de Sangre Periférica/métodos , Trasplante Autólogo
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