Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 98
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Mol Pharm ; 21(7): 3240-3255, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38785196

RESUMEN

Inhibitors of a DNA repair enzyme known as polynucleotide kinase 3'-phosphatase (PNKP) are expected to show synergistic cytotoxicity in combination with topoisomerase I (TOP1) inhibitors in cancer. In this study, the synergistic cytotoxicity of a novel inhibitor of PNKP, i.e., A83B4C63, with a potent TOP1 inhibitor, i.e., SN-38, against colorectal cancer cells was investigated. Polymeric micelles (PMs) for preferred tumor delivery of A83B4C63, developed through physical encapsulation of this compound in methoxy poly(ethylene oxide)-poly(α-benzyl carboxylate-ε-caprolactone) (mPEO-b-PBCL) micelles, were combined with SN-38 in free or PM form. The PM form of SN-38 was prepared through chemical conjugation of SN-38 to the functional end group of mPEO-b-PBCL and further assembly of mPEO-b-PBCL-SN-38 in water. Moreover, mixed micelles composed of mPEO-b-PBCL and mPEO-b-PBCL-SN-38 were used to co-load A83B4C63 and SN-38 in the same nanoformulation. The loading content (% w/w) of the SN-38 and A83B4C63 to mPEO-b-PBCL in the co-loaded formulation was 7.91 ± 0.66 and 16.13 ± 0.11% (w/w), respectively, compared to 15.67 ± 0.34 (% w/w) and 23.06 ± 0.63 (% w/w) for mPEO-b-PBCL micelles loading individual drugs. Notably, the average diameter of PMs co-encapsulating both SN-38 and A83B4C63 was larger than that of PMs encapsulating either of these compounds alone but still lower than 60 nm. The release of A83B4C63 from PMs co-encapsulating both drugs was 76.36 ± 1.41% within 24 h, which was significantly higher than that of A83B4C63-encapsulated micelles (42.70 ± 0.72%). In contrast, the release of SN-38 from PMs co-encapsulating both drugs was 44.15 ± 2.61% at 24 h, which was significantly lower than that of SN-38-conjugated PMs (74.16 ± 3.65%). Cytotoxicity evaluations by the MTS assay as analyzed by the Combenefit software suggested a clear synergy between PM/A83B4C63 (at a concentration range of 10-40 µM) and free SN-38 (at a concentration range of 0.001-1 µM). The synergistic cytotoxic concentration range for SN-38 was narrowed down to 0.1-1 or 0.01-1 µM when combined with PM/A83B4C63 at 10 or 20-40 µM, respectively. In general, PMs co-encapsulating A83B4C63 and SN-38 at drug concentrations within the synergistic range (10 µM for A83B4C63 and 0.05-1 µM for SN-38) showed slightly less enhancement of SN-38 anticancer activity than a combination of individual micelles, i.e., A83B4C63 PMs + SN-38 PMs at the same molar concentrations. This was attributed to the slower release of SN-38 from the SN-38 and A83B4C63 co-encapsulated PMs compared to PMs only encapsulating SN-38. Cotreatment of cells with TOP1 inhibitors and A83B4C63 formulation enhanced the expression level of γ-HA2X, cleaved PARP, caspase-3, and caspase-7 in most cases. This trend was more consistent and notable for PMs co-encapsulating both A83B4C63 and SN-38. The overall result from the study shows a synergy between PMs of SN-38 and A83B4C63 as a mixture of two PMs for individual drugs or PMs co-encapsulating both drugs.


Asunto(s)
Neoplasias Colorrectales , Irinotecán , Micelas , Inhibidores de Topoisomerasa I , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Irinotecán/farmacología , Irinotecán/administración & dosificación , Inhibidores de Topoisomerasa I/farmacología , Inhibidores de Topoisomerasa I/administración & dosificación , Inhibidores de Topoisomerasa I/química , Línea Celular Tumoral , Animales , Ratones , Nanomedicina/métodos , Sinergismo Farmacológico , ADN-Topoisomerasas de Tipo I/metabolismo , Nanopartículas/química , Ensayos Antitumor por Modelo de Xenoinjerto , Poliésteres/química , Fosfotransferasas (Aceptor de Grupo Alcohol) , Enzimas Reparadoras del ADN
2.
J Am Chem Soc ; 145(31): 17042-17055, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37524069

RESUMEN

New synthetic hybrid materials and their increasing complexity have placed growing demands on crystal growth for single-crystal X-ray diffraction analysis. Unfortunately, not all chemical systems are conducive to the isolation of single crystals for traditional characterization. Here, small-molecule serial femtosecond crystallography (smSFX) at atomic resolution (0.833 Å) is employed to characterize microcrystalline silver n-alkanethiolates with various alkyl chain lengths at X-ray free electron laser facilities, resolving long-standing controversies regarding the atomic connectivity and odd-even effects of layer stacking. smSFX provides high-quality crystal structures directly from the powder of the true unknowns, a capability that is particularly useful for systems having notoriously small or defective crystals. We present crystal structures of silver n-butanethiolate (C4), silver n-hexanethiolate (C6), and silver n-nonanethiolate (C9). We show that an odd-even effect originates from the orientation of the terminal methyl group and its role in packing efficiency. We also propose a secondary odd-even effect involving multiple mosaic blocks in the crystals containing even-numbered chains, identified by selected-area electron diffraction measurements. We conclude with a discussion of the merits of the synthetic preparation for the preparation of microdiffraction specimens and compare the long-range order in these crystals to that of self-assembled monolayers.

3.
BMC Public Health ; 23(1): 1512, 2023 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-37559021

RESUMEN

BACKGROUND: In recent years, the food security and dietary quality of many Iranian families have deteriorated due to unprecedented inflation. Nutrition education programs can be an effective and inexpensive method to improve food quality and security. The present study aimed to investigate the effect of a comprehensive nutrition education program for low-income women who are heads of households and are covered by the Zanjan province's welfare. METHODS: The food security of 2600 female-headed households covered by the Welfare of Zanjan province was evaluated using a standard 6-item questionnaire. A total of 600 women with the highest food insecurity scores were selected for the comprehensive nutrition education program. The participants received six sessions of 1.5 h of courses about how to improve the quality of their diets and manage their budgets and be physically active. At the beginning of the study and one month after the completion of the intervention, the participants were asked to complete a questionnaire designed and validated by the investigators. The scores of each section before and after the intervention were compared using paired t-test method and p values ​​of < 0.05 were considered statistically significant. RESULTS: The prevalence of severe food insecurity among female-headed households who receive welfare support in Abhar, Khodabandeh, and Zanjan cities was 59.5%, 75%, and 62%, respectively. A total of 505 participants successfully completed the courses. After completion of the educational intervention, diet quality, physical activity, budgeting, and food safety scores of the participants increased by 6%, 4%, 4%, and 5%, respectively, which were statistically significant (p < 0.001). However, no significant difference was observed in the food insecurity scores. CONCLUSION: The comprehensive nutrition education program without financial or nutritional support can have a small but significant impact on the improvement of the nutritional behaviors and dietary quality of low-income people.


Asunto(s)
Abastecimiento de Alimentos , Estado Nutricional , Femenino , Humanos , Irán/epidemiología , Dieta , Seguridad Alimentaria
4.
Magn Reson Chem ; 61(6): 356-362, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36882383

RESUMEN

The three possible 1-(n-pyridinyl)butane-1,3-diones (nPM) have been synthesized. Structures, tautomerism, and conformations are investigated by means of DFT calculations. 1 H and 13 C NMR spectra are assigned, and deuterium isotope effects on 13 C chemical shifts have been measured. Analysis of the isotope effects leads to the equilibrium constants of the keto-enol tautomers. Some interesting differences are seen between the three compounds and the phenyl analogs. The isotope effects can also rank the hydrogen bonds of the compounds, with the one with nitrogen in the three positions of the pyridine ring as the weakest. Structures, conformers, energies, and NMR nuclear shieldings are calculated using DFT calculations at the B3LYP/6-311++G(d,p) level.

5.
J Synchrotron Radiat ; 29(Pt 2): 331-346, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35254295

RESUMEN

The Sample Environment and Characterization (SEC) group of the European X-ray Free-Electron Laser (EuXFEL) develops sample delivery systems for the various scientific instruments, including systems for the injection of liquid samples that enable serial femtosecond X-ray crystallography (SFX) and single-particle imaging (SPI) experiments, among others. For rapid prototyping of various device types and materials, sub-micrometre precision 3D printers are used to address the specific experimental conditions of SFX and SPI by providing a large number of devices with reliable performance. This work presents the current pool of 3D printed liquid sample delivery devices, based on the two-photon polymerization (2PP) technique. These devices encompass gas dynamic virtual nozzles (GDVNs), mixing-GDVNs, high-viscosity extruders (HVEs) and electrospray conical capillary tips (CCTs) with highly reproducible geometric features that are suitable for time-resolved SFX and SPI experiments at XFEL facilities. Liquid sample injection setups and infrastructure on the Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX) instrument are described, this being the instrument which is designated for biological structure determination at the EuXFEL.


Asunto(s)
Rayos Láser , Impresión Tridimensional , Cristalografía por Rayos X , Viscosidad , Rayos X
6.
Mol Pharm ; 19(6): 1825-1838, 2022 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-35271294

RESUMEN

The disruption of polynucleotide kinase/phosphatase (PNKP) in colorectal cancer (CRC) cells deficient in phosphatase and tensin homolog (PTEN) is expected to lead to the loss of cell viability by a process known as synthetic lethality. In previous studies, we have reported on the encapsulation of a novel inhibitor of PNKP, namely, A83B4C63, in polymeric micelles and its activity in slowing the growth of PTEN-deficient CRC cells as well as subcutaneous xenografts. In this study, to enhance drug delivery and specificity to CRC tumors, the surface of polymeric micelles carrying A83B4C63 was modified with GE11, a peptide targeting epidermal growth factor receptor (EGFR) overexpressed in about 70% of CRC tumors. Using molecular dynamics (MD) simulations, we assessed the binding site and affinity of GE11 for EGFR. The GE11-modified micelles, tagged with a near-infrared fluorophore, showed enhanced internalization by EGFR-overexpressing CRC cells in vitro and a trend toward increased primary tumor homing in an orthotopic CRC xenograft in vivo. In line with these observations, the GE11 modification of polymeric micelles was shown to positively contribute to the improved therapeutic activity of encapsulated A83B4C63 against HCT116-PTEN-/- cells in vitro and that of orthotopic CRC xenograft in vivo. In conclusion, our results provided proof of principle evidence for the potential benefit of EGFR targeted polymeric micellar formulations of A83B4C63 as monotherapeutics for aggressive and metastatic CRC tumors but at the same time highlighted the need for the development of EGFR ligands with improved physiological stability and EGFR binding.


Asunto(s)
Neoplasias Colorrectales , Micelas , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Reparación del ADN , Enzimas Reparadoras del ADN/metabolismo , Receptores ErbB/metabolismo , Xenoinjertos , Humanos , Fosfotransferasas (Aceptor de Grupo Alcohol) , Polímeros/química , Distribución Tisular
7.
Health Care Women Int ; 43(1-3): 367-375, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34432616

RESUMEN

The authors' aim in this study was to investigate the relationship between chronic periodontitis and liver status using alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in women patients. The researchers conducted a case-control study on women patients referred to Dental School. The researchers collected 5 ml of peripheral venous blood from women for the laboratory process after performing periodontal examination. Participants were 124 women aged 25-50 years (62 cases and 62 control). The difference in serum levels of ALT and the difference in serum levels of AST between the two groups were not statistically significant. However, there was a significant correlation between liver enzymes and periodontitis parameters.


Asunto(s)
Periodontitis Crónica , Adulto , Alanina Transaminasa , Aspartato Aminotransferasas , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad
8.
Molecules ; 26(24)2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-34946735

RESUMEN

The vibrational NH stretching transitions in secondary amines with intramolecular NH···O hydrogen bonds were investigated by experimental and theoretical methods, considering a large number of compounds and covering a wide range of stretching wavenumbers. The assignment of the NH stretching transitions in the experimental IR spectra was, in several instances, supported by measurement of the corresponding ND wavenumbers and by correlation with the observed NH proton chemical shifts. The observed wavenumbers were correlated with theoretical wavenumbers predicted with B3LYP density functional theory, using the basis sets 6-311++G(d,p) and 6-31G(d) and considering the harmonic as well as the anharmonic VPT2 approximation. Excellent correlations were established between observed wavenumbers and calculated harmonic values. However, the correlations were non-linear, in contrast to the results of previous investigations of the corresponding OH···O systems. The anharmonic VPT2 wavenumbers were found to be linearly related to the corresponding harmonic values. The results provide correlation equations for the prediction of NH stretching bands on the basis of standard B3LYP/6-311++G(d,p) and B3LYP/6-31G(d) harmonic analyses, with standard deviations close to 38 cm-1. This is significant because the full anharmonic VPT2 analysis tends to be impractical for large molecules, requiring orders of magnitude more computing time than the harmonic analysis.

9.
Mol Pharm ; 17(4): 1377-1386, 2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32023064

RESUMEN

In this study, we tested whether the extent of drug presence in the heart contributes to the elevated cardiovascular risk of nonsteroidal anti-inflammatory drugs (NSAIDs). A fluorescently tagged nanoformulation of an NSAID with high cardiovascular (CV) risk (diclofenac) was developed as diclofenac ethyl ester (DFEE) encapsulated in traceable (cyanine-5.5-labeled) polymeric micelles (DFEE-TM) based on methoxypoly(ethylene oxide)-block-poly(ε-caprolactone)(PEO-b-PCL) (MW, 5000:3500 g/mol). Diclofenac pharmacokinetics and tissue distribution, as well as ex vivo near-infrared images of organs and whole bodies, were compared between healthy rats and rats with adjuvant arthritis (AA) following the administration of a single intravenous (iv) dose of DFEE-TM. Moreover, the biodistribution and antiarthritic activity of DFEE-TM were compared with those of free diclofenac (once-daily intraperitoneal, ip, 10 mg/kg for 7 days). The concentration ratios of cytochrome-P450-mediated cardiotoxic (20-hydroxyeicosatetraenoic acid) over cardioprotective (epoxyeicosatrienoic acids) metabolites of arachidonic acid (ArA) in the heart, kidneys, and plasma were measured as markers of cardiotoxicity. The nanocarrier was found in the joints of AA, but not in those of healthy rats. Both free diclofenac and DFEE-TM comparably controlled AA. Diclofenac delivery via PEO-b-PCL micelles reduced the accumulation of diclofenac in the heart of AA rats. Despite similar antiarthritic activity, the polymeric micellar formulation showed a reduction in the ratio of cardiotoxic-over-cardioprotective eicosanoids of ArA in the heart and plasma of AA rats. The results showed the positive effect of diclofenac prodrug nanodelivery in changing the normal biodistribution of diclofenac away from the heart, leading to lowered diclofenac-induced biomarkers of cardiotoxicity in the heart and plasma of AA rats.


Asunto(s)
Ácido Araquidónico/metabolismo , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Diclofenaco/efectos adversos , Diclofenaco/farmacología , Corazón/efectos de los fármacos , Animales , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/farmacología , Caproatos/química , Portadores de Fármacos/química , Ácidos Hidroxieicosatetraenoicos/química , Lactonas/química , Masculino , Micelas , Nanopartículas/química , Poliésteres/química , Polímeros/química , Ratas , Ratas Sprague-Dawley , Distribución Tisular
10.
Mol Pharm ; 17(5): 1470-1481, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32233491

RESUMEN

Polymeric micellar nanoparticles represent versatile and biocompatible platforms for targeted drug delivery. However, tracking their biodistribution, stability, and clearance profile in vivo is challenging. The goal of this study was to prepare surface-modified micelles with peptide GE11 for targeting the epidermal growth factor receptor (EGFR). In vitro fluorescence studies demonstrated significantly higher internalization of GE11 micelles into EGFR-expressing HCT116 colon cancer cells versus EGFR-negative SW620 cells. Azo coupling chemistry of tyrosine residues in the peptide backbone with aryl diazonium salts was used to label the micelles with radionuclide 64Cu for positron emission tomography (PET) imaging. In vivo analysis of 64Cu-labeled micelles showed prolonged blood circulation and predominant hepatobiliary clearance. The biodistribution profile of EGFR-targeting GE11 micelles was compared with nontargeting HW12 micelles in HCT116 tumor-bearing mice. PET revealed increasing tumor-to-muscle ratios for both micelles over 48 h. Accumulation of GE11-containing micelles in HCT116 tumors was higher compared to HW12-decorated micelles. Our data suggest that the efficacy of image-guided therapies with micellar nanoparticles could be enhanced by active targeting, as demonstrated with cancer biomarker EGFR.


Asunto(s)
Neoplasias Colorrectales/diagnóstico por imagen , Radioisótopos de Cobre/farmacocinética , Receptores ErbB/antagonistas & inhibidores , Imagen Molecular/métodos , Péptidos/metabolismo , Radiofármacos/síntesis química , Animales , Línea Celular Tumoral , Humanos , Marcaje Isotópico , Ratones , Ratones Endogámicos BALB C , Micelas , Nanopartículas , Polímeros/metabolismo , Tomografía de Emisión de Positrones , Radiofármacos/farmacocinética
11.
J Synchrotron Radiat ; 26(Pt 2): 406-412, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30855249

RESUMEN

Serial synchrotron crystallography allows low X-ray dose, room-temperature crystal structures of proteins to be determined from a population of microcrystals. Protein production and crystallization is a non-trivial procedure and it is essential to have X-ray-compatible sample environments that keep sample consumption low and the crystals in their native environment. This article presents a fast and optimized manufacturing route to metal-polyimide microfluidic flow-focusing devices which allow for the collection of X-ray diffraction data in flow. The flow-focusing conditions allow for sample consumption to be significantly decreased, while also opening up the possibility of more complex experiments such as rapid mixing for time-resolved serial crystallography. This high-repetition-rate experiment allows for full datasets to be obtained quickly (∼1 h) from crystal slurries in liquid flow. The X-ray compatible microfluidic chips are easily manufacturable, reliable and durable and require sample-flow rates on the order of only 30 µl h-1.

12.
Langmuir ; 35(32): 10435-10445, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31318572

RESUMEN

Advances in modern interface- and material sciences often rely on the understanding of a system's structure-function relationship. Designing reproducible experiments that yield in situ time-resolved structural information at fast time scales is therefore of great interest, e.g., for better understanding the early stages of self-assembly or other phase transitions. However, it can be challenging to accurately control experimental conditions, especially when samples are only available in small amounts, prone to agglomeration, or if X-ray compatibility is required. We address these challenges by presenting a microfluidic chip for triggering dynamics via rapid diffusive mixing for in situ time-resolved X-ray investigations. This polyimide/Kapton-only-based device can be used to study the structural dynamics and phase transitions of a wide range of colloidal and soft matter samples down to millisecond time scales. The novel multiangle laser ablation three-dimensional (3D) microstructuring approach combines, for the first time, the highly desirable characteristics of Kapton (high X-ray stability with low background, organic solvent compatibility) with a 3D flow-focusing geometry that minimizes mixing dispersion and wall agglomeration. As a model system, to demonstrate the performance of these 3D Kapton microfluidic devices, we selected the non-solvent-induced self-assembly of biocompatible and amphiphilic diblock copolymers. We then followed their structural evolution in situ at millisecond time scales using on-the-chip time-resolved small-angle X-ray scattering under continuous-flow conditions. Combined with complementary results from 3D finite-element method computational fluid dynamics simulations, we find that the nonsolvent mixing is mostly complete within a few tens of milliseconds, which triggers initial spherical micelle formation, while structural transitions into micelle lattices and their deswelling only occur on the hundreds of milliseconds to second time scale. These results could have an important implication for the design and formulation of amphiphilic polymer nanoparticles for industrial applications and their use as drug-delivery systems in medicine.

13.
Nurs Ethics ; 26(7-8): 2195-2203, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30394850

RESUMEN

BACKGROUND: Nursing is a profession that has always been accompanied with common ethical concerns. There are some evidences which indicate that narrative writing on traumatic experiences may improve an individual's emotional health. OBJECTIVE: This study aimed to determine the effectiveness of narrative writing on moral distress of nurses working in intensive care unit. RESEARCH DESIGN: This study was a clinical trial with pre- and post-test design. The frequency and intensity of moral distress was measured by a valid and reliable questionnaire (Corely) at baseline and after 8 weeks. The intervention group was asked to write about their deepest emotions and stressful experiences in the intensive care unit for 8 weeks. PARTICIPANTS AND RESEARCH CONTEXT: Using consensus sampling, 120 nurses of intensive care unit and neonatal intensive care unit of the teaching hospitals (in Iran) were invited to and were randomly allocated into the intervention and control groups. ETHICAL CONSIDERATIONS: Participation was voluntary, data were anonymized, and the confidentiality of the participating nurses and their institutions maintained. The ethical approval was obtained from an IRB or research ethics committee. FINDINGS: In total, 106 nurses completed the trial consisting of 87.75% females. The mean work experience of nurses in the intervention and control groups was 7.21 ± 4.96 and 8.28 ± 5.45 years, respectively. Independent t-test showed no statistical difference neither in the intensity of moral distress (P = 0.8), nor in its frequency (P = 0.5) between the two groups. DISCUSSION: As nurses constantly face ethical tensions, moral distress is a phenomenon that results from the different situations of critical care units. Their concern about receiving negative feedback from the managerial level may have influenced the outcome of the intervention. CONCLUSION: Narratives writing by the nurses showed no effect on reducing the intensity and frequency of moral distress. It seems that due to the intensity of moral distress in clinical settings, we need to test variety solutions to reduce the problem.


Asunto(s)
Enfermeras y Enfermeros/psicología , Trastornos por Estrés Postraumático/terapia , Escritura , Adulto , Actitud del Personal de Salud , Enfermería de Cuidados Críticos/métodos , Enfermería de Cuidados Críticos/normas , Femenino , Humanos , Unidades de Cuidados Intensivos/organización & administración , Unidades de Cuidados Intensivos/normas , Unidades de Cuidados Intensivos/estadística & datos numéricos , Irán , Masculino , Persona de Mediana Edad , Enfermeras y Enfermeros/estadística & datos numéricos , Trastornos por Estrés Postraumático/psicología , Encuestas y Cuestionarios
14.
J Cell Mol Med ; 22(4): 2210-2219, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29397578

RESUMEN

Activation of hepatic stellate cells (HSCs) is an integral component of the wound-healing process in liver injury/inflammation. However, uncontrolled activation of HSCs leads to constant secretion of collagen-rich extracellular matrix (ECM) proteins, resulting in liver fibrosis. The enhanced ECM synthesis/secretion demands an uninterrupted supply of intracellular energy; however, there is a paucity of data on the bioenergetics, particularly the mitochondrial (mito) metabolism of fibrogenic HSCs. Here, using human and rat HSCs in vitro, we show that the mito-respiration, mito-membrane potential (Δψm) and cellular 'bioenergetic signature' distinguish fibrogenic HSCs from normal, less-active HSCs. Ex vivo, HSCs from mouse and rat models of liver fibrosis further confirmed the altered 'bioenergetic signature' of fibrogenic HSCs. Importantly, the distinctive elevation in mito-Δψm sensitized fibrogenic HSCs for selective inhibition by mitotropic doxorubicin while normal, less-active HSCs and healthy human primary hepatocytes remained minimally affected if not, unaffected. Thus, the increased mito-Δψm may provide an opportunity to selectively target fibrogenic HSCs in liver fibrosis.


Asunto(s)
Doxorrubicina/farmacología , Células Estrelladas Hepáticas/metabolismo , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Mitocondrias Hepáticas/metabolismo , Animales , Línea Celular , Metabolismo Energético , Células Estrelladas Hepáticas/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Análisis de Flujos Metabólicos , Mitocondrias Hepáticas/efectos de los fármacos , Ratas
15.
Mol Pharm ; 15(6): 2316-2326, 2018 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-29688721

RESUMEN

There is increasing interest in developing and applying DNA repair inhibitors in cancer treatment to augment the efficacy of radiation and conventional genotoxic chemotherapy. However, targeting the inhibitor is required to avoid reducing the repair capacity of normal tissue. The aim of this study was to develop nanodelivery systems for the encapsulation of novel imidopiperidine-based inhibitors of the DNA 3'-phosphatase activity of polynucleotide kinase/phosphatase (PNKP), a DNA repair enzyme that plays a critical role in rejoining DNA single- and double-strand breaks. For this purpose, newly identified hit compounds with potent PNKP inhibitory activity, imidopiperidines A12B4C50 and A83B4C63 were encapsulated in polymeric micelles of different poly(ethylene oxide)- b-poly(ε-caprolactone) (PEO- b-PCL)-based structures. Our results showed efficient loading of A12B4C50 and A83B4C63 in PEO- b-PCLs with pendent carboxyl and benzyl carboxylate groups, respectively, and relatively slow release over 24 h. Both free and encapsulated inhibitors were able to sensitize HCT116 cells to radiation and the topoisomerase I poison, irinotecan. In addition, the encapsulated inhibitors were capable of inducing synthetic lethalilty in phosphatase and tensin homologue (PTEN)-deficient cells. We also established the validity of the peptide GE11 as a suitable ligand for active targeted delivery of nanoencapsulated drugs to colorectal cancer cells overexpressing epidermal growth factor receptor (EGFR). Our results show the potential of nanoencapsulated inhibitors of PNKP as either mono or combined therapeutic agents for colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/terapia , Enzimas Reparadoras del ADN/antagonistas & inhibidores , Nanocápsulas/química , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Piperidinas/administración & dosificación , Mutaciones Letales Sintéticas/efectos de los fármacos , Quimioradioterapia/métodos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Reparación del ADN/efectos de los fármacos , Reparación del ADN/efectos de la radiación , Enzimas Reparadoras del ADN/metabolismo , Composición de Medicamentos/métodos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Células HCT116 , Humanos , Irinotecán/farmacología , Micelas , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Piperidinas/farmacología , Radiación Ionizante
16.
Mol Pharm ; 15(3): 882-891, 2018 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-29357260

RESUMEN

Multidrug resistance (MDR) is the major obstacle for chemotherapy. In a previous study, we have successfully synthesized a novel doxorubicin (DOX) derivative modified by triphenylphosphonium (TPP) to realize mitochondrial delivery of DOX and showed the potential of this compound to overcome DOX resistance in MDA-MB-435/DOX cells. (1) To introduce specificity for DOX-TPP to cancer cells, here we report on the conjugation of DOX-TPP to hyaluronic acid (HA) by hydrazone bond with adipic acid dihydrazide (ADH) as the acid-responsive linker, producing HA- hydra-DOX-TPP nanoparticles. Hyaluronic acid (HA) is a natural water-soluble linear glycosaminoglycan, which was hypothesized to increase the accumulation of nanoparticles containing DOX-TPP in the mitochondria of tumor cells upon systemic administration, overcoming DOX resistance, in vivo. Our results showed HA- hydra-DOX-TPP to self-assemble to core/shell nanoparticles of good dispersibility and effective release of DOX-TPP from the HA- hydra-DOX-TPP conjugate in cancer cells, which was followed by enhanced DOX mitochondria accumulation. The HA- hydra-DOX-TPP nanoparticles also showed improved anticancer effects, better tumor cell apoptosis, and better safety profile compared to free DOX in MCF-7/ADR bearing mice.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/administración & dosificación , Mitocondrias/metabolismo , Nanoconjugados/química , Animales , Antibióticos Antineoplásicos/química , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Doxorrubicina/química , Liberación de Fármacos , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Femenino , Humanos , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/química , Concentración de Iones de Hidrógeno , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Células MCF-7 , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mitocondrias/efectos de los fármacos , Compuestos Organofosforados/administración & dosificación , Compuestos Organofosforados/química , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Acta Pharmacol Sin ; 39(10): 1681-1692, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29849132

RESUMEN

Breast cancer is the leading cause of cancer-related death for women, and multidrug resistance (MDR) is the major obstacle faced by chemotherapy for breast cancer. We have previously synthesized a doxorubicin (DOX) derivative by conjugating DOX with triphenylphosphonium (TPP) to achieve mitochondrial delivery, which induced higher cytotoxicity in drug-resistant breast cancer cells than DOX itself. Due to its amphiphilicity, TPP-DOX is difficult to physically entrap in nanocarriers. Thus, we linked it to hyaluronic acid (HA) by a novel ionic bond utilizing the specific bromide ion of TPP to form supra-molecular self-assembled structures (HA-ionic-TPP-DOX). The product was analyzed uisng 1H-NMR, 13C-NMR and mass spectrometry. The HA nanocarriers (HA-ionic-TPP-DOX) were shown to self-assemble into spherical nanoparticles, and sensitive to acidic pH in terms of morphology and drug release. Compared with free DOX, HA-ionic-TPP-DOX produced much greater intracellular DOX accumulation and mitochondrial localization, leading to increased ROS production, slightly decreased mitochondrial membrane potential, increased cytotoxicity in MCF-7/ADR cells and enhanced tumor targeting in vivo. In xenotransplant zebrafish model with the MCF-7/ADR cell line, both TPP-DOX and HA-ionic-TPP-DOX inhibited tumor cell proliferation without inducing significant side effects compared with free DOX. In addition, we observed a better anti-tumor effect of HA-ionic-TPP-DOX on MCF-7/ADR cells in zebrafish than that of TPP-DOX treatment. Furthermore, HA-ionic-DOX-TPP exhibited favorable biocompatibility and anti-tumor effects in MCF-7/ADR tumor-bearing nude mice in comparison with the effects of TPP-DOX and DOX, suggesting the potential of HA-ionic-TPP-DOX for the targeted delivery and controlled release of TPP-DOX, which can lead to the sensitization of resistant breast tumors.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/uso terapéutico , Portadores de Fármacos/química , Ácido Hialurónico/química , Mitocondrias/metabolismo , Animales , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Doxorrubicina/química , Liberación de Fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Humanos , Células MCF-7 , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos BALB C , Ratones Desnudos , Compuestos Onio/química , Compuestos Organofosforados/química , Pez Cebra
18.
J Pharm Pharm Sci ; 21(1s): 103s-116s, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30011392

RESUMEN

PURPOSE: Alberta Health Services (AHS) recommends the adoption of a new neonatal multi-trace element formulation containing zinc sulfate, copper sulfate, selenious acid and sodium iodide to be compounded internally in appropriate AHS pharmacies. The objective of this study was to assess the physicochemical stability of this formulation under commonly used storage conditions. METHOD: Three batches of trace element solution were compounded by University of Alberta Hospital pharmacy staff using sterile compounding procedures. Appropriate amount of zinc sulfate (500 mg/mL), copper sulfate (40 mg/mL), selenious acid (4 mg/mL), sodium iodide (2 mg/mL) and sterile water for injection were mixed. Samples from each batch were divided in individual vials and syringes for each time point and kept protected from light either at room temperature (15-30°C) or fridge (2-8°C). Vial samples were also kept at room temperature for 12 h and then transferred to fridge. Vial samples were analyzed at time 0, 12 h, and 1, 3, 7, 9, 30, 60, 90 days for their physical appearance and pH, then centrifuged and assessed for the soluble zinc (atomic absorption), copper (atomic absorption), selenium (ICP-MS) and iodine (HPLC and ICP-MS) concentrations. Syringe samples were tested at time 0 and 12 h for element concentrations. RESULTS: Under all storage conditions, when stored in vials, samples' appearance, pH and soluble zinc, copper and selenium concentrations stayed within the USP acceptable limits up to 90 days. Iodine concentration was within the permitted limits only up to 7 days. The USP recommended HPLC method of iodine analysis seemed inadequate for this preparation and needed modifications, through frequent washing of the column with KI (2 %) solution. Samples kept in syringes at room temperature, showed lower than permitted concentration of Zn at 12h in this study. CONCLUSION: The AHS neonatal multi-trace element formulation seem to be physio-chemically stable up to 7 days in all three storage conditions when kept in vials.  A decline in iodine concentration is seen after 7 days irrespective of storage conditions. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.


Asunto(s)
Atención a la Salud , Oligoelementos/química , Alberta , Química Física , Estabilidad de Medicamentos , Humanos , Soluciones , Temperatura
19.
J Pharm Pharm Sci ; 21(1): 143-159, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29789104

RESUMEN

PURPOSE: Silibinin, is a natural compound, which has shown anticancer activity in various malignancies. In this study, we evaluated the anticancer effects of silibinin in B16-F10 melanoma cells and developed a novel thermoresponsive hydrogel for local delivery of this compound. METHOD: A thermoresponsive hydrogel loaded with silibinin was prepared using triblock copolymers of poly[(α-benzyl carboxylate-e-caprolactone)-co-(α-carboxyl-e-caprolactone)]ran-b-PEG-b-[(α-benzyl carboxylate-e-caprolactone) -co-(α-carboxyl-e-caprolactone)]ran (PCBCL-b-PEG-b-PCBCL), namely PolyGelTM, and compared with a Pluronic F-127 formulation of silibinin. Sol-gel transition temperature of hydrogels was measured by inverse flow method and modulated differential scanning calorimetry (MDSC). Silibinin loading efficiency was measured by HPLC. The MTT and clonogenic assays were used to assess the cytotoxicity and anti-proliferative effects of silibinin on B16-F10 melanoma cells. Flow cytotmetry was used to quantify the induced level of apoptosis and measure the intracellular level of activated STAT3 (pSTAT3) following silibinin treatment in B16.F10 cells. The effects of silibinin on the activation of oncogenic proteins were also evaluated by western blot. RESULTS: Silibinin inhibited cell proliferation (IC50 = 67 µM), provoked cell cycle arrest, induced apoptosis, suppressed key oncogenic pathways (i.e STAT3 and MEK/ERK), and enhanced the cytotoxic effects of doxorubicin in B16-F10 cells. Both PolyGelTM and Pluronic F-127 hydrogels were effective in loading silibinin. A lower drug release pattern within 24h, fitting first- order release kinetics, was observed for the release of silibinin from both gels compared to free drug.  PolyGelTM demonstrated enhanced percutaneous absorption of silibinin through increasing mouse skin intracellular lipid fluidity as documented by DSC of skin following PolyGelTM use. Silibinin loaded in PolyGel TM inhibited the growth of B16-F10 cells (IC50 = 30 µM) and effectively suppressed pSTAT3 activity in B16-F10 cells at 10 µM. CONCLUSION: Our results imply a great potential for PolyGel TM formulations of silibinin for local treatment of malignant melanoma. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's content page.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Caproatos/química , Lactonas/química , Melanoma/tratamiento farmacológico , Polietilenglicoles/química , Silibina/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Temperatura , Animales , Antineoplásicos Fitogénicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Hidrogeles/química , Hidrogeles/farmacología , Melanoma/patología , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Silibina/química , Neoplasias Cutáneas/patología , Melanoma Cutáneo Maligno
20.
Iran J Med Sci ; 43(5): 554-559, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30214110

RESUMEN

Pectus excavatum is the most common congenital deformity of the chest wall. The most frequently used techniques include Ravitch (costochondral resection) and Nuss (minimally invasive pectus repair of pectus excavatum [MIRPE]). The Nuss technique includes using temporary metallic bars without costochondral resection to correct the chest wall deformity. Modified MIRPE can be learned easily and performed safely with few complications. There are no reports of successful MIRPE in Iran, although the Ravitch technique is well known. In the present study, we report the first Iranian experience with the modified Nuss procedure in 5 patients with pectus excavatum (age range=13-48 y). All the patients suffered from low self-esteem, and one of them complained of low exercise capacity and occasional chest pain. With single-lung ventilation and sternal elevation, an introducer was entered into the right thoracic cavity and retrosternal tunneling was performed under thoracoscopic vision. The introducer was passed to the left thoracic cavity and exited on the left thoracic wall. A titanium plate bar was implanted and fixed with stabilizers. There were no cases of mortality, and all the patients were discharged in good conditions within 2 weeks. Postoperative complications consisted of 1 case of pneumothorax and 2 cases of fixed bar protrusion. The present case series indicated that a skilled thoracoscopic surgeon is able to do the Nuss procedure in Iranian patients with symmetrical pectus excavatum with few complications. However, mixed or redo cases require more expertise.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA