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2.
Am J Kidney Dis ; 81(1): 67-78.e1, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35948116

RESUMEN

RATIONALE & OBJECTIVE: Patients with advanced chronic kidney disease (CKD) have been reported to experience profound psychosocial distress. Other work has established that patients with CKD from marginalized populations (including individuals who on the basis of race often face racism and related discrimination, termed "racialization") experience health care inequities. Given limited information on the intersection of these 2 phenomena, we assessed the association of psychosocial distress with racialized status and immigrant status in Canadians with advanced CKD. STUDY DESIGN: Secondary analysis of cross-sectional data. SETTING & PARTICIPANTS: 536 patients with advanced CKD (estimated glomerular filtration rate<30mL/min/1.73m2, with or without kidney replacement therapy) from multiple clinical centers in Toronto. EXPOSURE: Racialized status (individuals who identify as Asian or as African, Caribbean, or Black Canadian), immigrant status, and combined immigrant-racialized status. OUTCOME: Psychosocial distress, defined as the presence of depression, anxiety, or social difficulties (ie, a score of≥10 points on the Patient Health Questionnaire 9, Generalized Anxiety Disorder 7, or Social Distress 16 scales, respectively). ANALYTICAL APPROACH: The independent associations of racialized status and immigrant status with psychosocial distress, depression, anxiety, and social difficulties were examined using univariable- and multivariable-adjusted logistic regression. RESULTS: Mean age of the 536 participants was 57±16 (SD) years, 62% were male, and 45% were immigrants. Of the sample, 58% were White, 22% were African, Caribbean, or Black Canadian, and 20% were Asian. Psychosocial distress was present in 36% of participants (depression in 19%, anxiety in 12%, and social difficulties in 31%). To assess the combined impact of racialized and immigrant status, we created a variable with mutually exclusive categories: White nonimmigrant, racialized nonimmigrant, White immigrant, and racialized immigrant participants. In our final multivariable-adjusted model, compared with White nonimmigrant participants, racialized immigrant participants were more likely to have psychosocial distress (OR, 2.96 [95% CI, 1.81-4.81]), depression (OR, 1.87 [95% CI, 1.05-3.34]), and social difficulties (OR, 3.36 [95% CI, 2.03-5.57]). Overall similar associations were seen for racialized nonimmigrants and for White immigrants. LIMITATIONS: Convenience sample; small subgroups; combined exposure variable grouping Asian and African, Caribbean, and Black participants together; lack of data about mechanisms. CONCLUSIONS: Both racialized and immigrant status based on self-report of demographic characteristics were associated with psychosocial distress among patients with advanced CKD. These patients may benefit from culturally competent psychosocial support. PLAIN-LANGUAGE SUMMARY: Psychosocial distress is frequent in patients with advanced chronic kidney disease and impacts quality of life and clinical outcomes. Psychosocial distress may be especially scarring in people who are racialized (marginalized on account of their membership in a particular racial group) and/or who are immigrants. We assessed the association of psychosocial distress with racialized and immigrant status in Canadians with advanced chronic kidney disease. Among 536 participants from multiple medical centers in Toronto, we found that racialized and immigrant participants were more likely to have psychosocial distress, depression, and social difficulties compared with White nonimmigrant participants. This is likely related to the multiple intersectional challenges, including experience with racism and discrimination that racialized immigrant patients may face. Further studies are needed to elucidate the specific factors that contribute to more distress. The potential impact of culturally competent and safe support for these patients will also need to be studied.


Asunto(s)
Emigrantes e Inmigrantes , Insuficiencia Renal Crónica , Humanos , Masculino , Adulto , Persona de Mediana Edad , Anciano , Femenino , Canadá/epidemiología , Estudios Transversales , Calidad de Vida , Grupos Raciales , Insuficiencia Renal Crónica/psicología
3.
J Chem Phys ; 154(17): 174903, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34241068

RESUMEN

Confinement has been shown to contribute to the dynamics of small molecules within nanoscale hydrophobic or hydrophilic cavities. Enclosure within a confined space can also influence energy transfer pathways, such as the enhancement of fluorescence over thermal relaxation. In this paper, the effect of confinement on the thermodynamic properties and reaction kinetics of small hydrophobic molecules confined in a soft polymeric template is detailed. A quasi-elastic neutron scattering experiment identified a substantial decrease in translational diffusion of pyrrole after solubilization within a hydrophobic cavity. This decrease in mobility is due to pyrrole's closer packing and increased density under confinement vs the bulk liquid. The decreased mobility and increased density explain the spontaneous polymerization reaction of pyrrole observed within the cavity. The precise characterization of the polymerization kinetics under confinement found that the reaction is independent of pyrrole concentration, consistent with the close packing density. Kinetic data also show that confinement dimensionality finds a thermodynamic expression in the transition state entropy. The dynamics and kinetics experiments reported here offer rare empirical insight into the important influence that cavity geometry places on the reactions they host.

4.
Colloids Surf B Biointerfaces ; 157: 407-416, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28633121

RESUMEN

Tearing of the rotator cuff commonly occurs as among one of the most frequently experienced tendon disorders. While treatment typically involves surgical repair, failure rates to achieve or sustain healing range from 20 to 90%. The insufficient capacity to recover damaged tendon to heal to the bone, especially at the enthesis, is primarily responsible for the failure rates reported. Various types of biomaterials with special structures have been developed to improve tendon-bone healing and tendon regeneration, and have received considerable attention for replacement, reconstruction, or reinforcement of tendon defects. In this review, we first give a brief introduction of the anatomy of the rotator cuff and then discuss various design strategies to augment rotator cuff repair. Furthermore, we highlight current biomaterials used for repair and their clinical applications as well as the limitations in the literature. We conclude this article with challenges and future directions in designing more advanced biomaterials for augmentation of rotator cuff repair.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Manguito de los Rotadores/cirugía , Animales , Materiales Biocompatibles/efectos adversos , Humanos , Tendones/cirugía , Cicatrización de Heridas/fisiología
5.
J Mater Chem B ; 4(22): 3959-3968, 2016 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-32263095

RESUMEN

In this study, a novel protein-polymer conjugate, d-α-tocopheryl polyethylene glycol succinate modified reduced bovine serum albumin (TPGS-Re-BSA, TRB), was synthesized for lipophilic anticancer drug delivery, and its unique ability to overcome drug resistance was explored. This conjugate was extensively characterized for its chemical structure, average molecular weight, secondary structure, degree of substitution, hydrophobicity, particle size and zeta potential. PTX-loaded nanoparticles (NPs) with diameters of 170-370 nm and drug loading efficiency of up to 13.62% were successfully prepared by the dialysis method. These drug-loaded NPs were found to exhibit a sustained release of PTX at pH 7.4, 6.5 and 5.5. Moreover, great anti-tumor activity in drug sensitive MCF-7 cells was observed in the in vitro anti-tumor studies. In particular, enhanced cytotoxicity and PTX-induced apoptosis were observed in the drug-resistant MCF-7/ADR cells compared to the Taxol and PTX-loaded BSA NPs. This could be attributed to the significant inhibition of P-gp activity and reduced ATP levels due to the presence of TRB NPs. Lastly, in vivo tumor inhibition assay verified the higher efficacy of TRB NPs. Overall, the results suggest that this TRB NPs could provide an effective carrier system for the delivery of anticancer agents.

6.
J Mater Chem B ; 4(27): 4675-4682, 2016 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32263239

RESUMEN

In this study, for effective oral cancer therapy, a new targeted and ROS-triggered drug delivery nanoplatform was developed from the RGD-PEG-TK-PLGA polymer, in which the ROS-responsive TK containing linker was connected with PEG and PLGA. RGD in the drug delivery system (DDS) presented here was used to target cancer cells. This new nanoplatform shows high stability, good targeting ability, excellent ROS sensitivity and excellent biocompatibility. Loaded with DOX and alpha-TOS, the formulated nanoparticles (NPs) demonstrate much better cellular uptake efficiency and higher inhibition performance towards the oral tongue Cal27 cancer cell line. In vivo anticancer evaluation indicates that DOX and alpha-TOS loaded RGD-PEG-TK-PLGA NPs have no toxicity to mice and showed significantly improved therapeutic efficacy against tumors. Therefore, this polymeric NP platform presents great potential as a new DDS for oral cancer chemotherapy.

7.
Biomaterials ; 74: 280-91, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26461120

RESUMEN

Hybrid drug delivery system containing both organic and inorganic nanocarriers is expected to achieve its complementary advantages for the aim of improving the performance of antineoplastic drugs in tumor therapy. Here we report the use of liposomes and gold nanoparticles to construct a liposome with a hybrid Cluster Bomb structure and discuss its unique multi-order drug release property for liver tumor treatment. A very simple method is used for the hybrid liposome preparation and involves mixing two solutions containing liposomes loaded with either non-covalent or covalent Paclitaxel (PTX, namely free PTX or PTX-conjugated GNPs, respectively) by different ratio of volume (25:75, 50:50, 25:75, v/v). Various mixed liposomes were tested to determine the optimal conditions for maximum drug delivery. The optimized liposome was then tested using xenograft Heps tumor-bearing mice and showed the best efficacy for chemotherapeutic inhibition of tumor at PTX liposome: PTX-conjugated GNP liposome of 25:75 ratio (v/v). This system allows for simple and easy preparation while providing a more accurate site- and time-release mode for tumor treatment using antitumor drugs.


Asunto(s)
Oro/química , Liposomas/química , Neoplasias Hepáticas/terapia , Células Hep G2 , Humanos
8.
Angew Chem Int Ed Engl ; 54(32): 9218-23, 2015 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-26119453

RESUMEN

Selective tumor targeting and drug delivery are critical for cancer treatment. Stimulus-sensitive nanoparticle (NP) systems have been designed to specifically respond to significant abnormalities in the tumor microenvironment, which could dramatically improve therapeutic performance in terms of enhanced efficiency, targetability, and reduced side-effects. We report the development of a novel L-cysteine-based poly (disulfide amide) (Cys-PDSA) family for fabricating redox-triggered NPs, with high hydrophobic drug loading capacity (up to 25 wt% docetaxel) and tunable properties. The polymers are synthesized through one-step rapid polycondensation of two nontoxic building blocks: L-cystine ester and versatile fatty diacids, which make the polymer redox responsive and give it a tunable polymer structure, respectively. Alterations to the diacid structure could rationally tune the physicochemical properties of the polymers and the corresponding NPs, leading to the control of NP size, hydrophobicity, degradation rate, redox response, and secondary self-assembly after NP reductive dissociation. In vitro and in vivo results demonstrate these NPs' excellent biocompatibility, high selectivity of redox-triggered drug release, and significant anticancer performance. This system provides a promising strategy for advanced anticancer theranostic applications.


Asunto(s)
Cisteína/química , Nanopartículas/química , Polímeros/química , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Disulfuros/química , Docetaxel , Portadores de Fármacos/química , Transferencia Resonante de Energía de Fluorescencia , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Neoplasias/tratamiento farmacológico , Oxidación-Reducción , Tamaño de la Partícula , Polietilenglicoles/química , Taxoides/administración & dosificación , Taxoides/química , Taxoides/toxicidad , Nanomedicina Teranóstica
9.
Analyst ; 140(1): 280-6, 2015 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-25381991

RESUMEN

To expand the application scope of nuclear magnetic resonance (NMR) technology in quantitative analysis of pharmaceutical ingredients, (19)F nuclear magnetic resonance ((19)F-NMR) spectroscopy has been employed as a simple, rapid, and reproducible approach for the detection of a fluorine-containing model drug, sitagliptin phosphate monohydrate (STG). ciprofloxacin (Cipro) has been used as the internal standard (IS). Influential factors, including the relaxation delay time (d1) and pulse angle, impacting the accuracy and precision of spectral data are systematically optimized. Method validation has been carried out in terms of precision and intermediate precision, linearity, limit of detection (LOD) and limit of quantification (LOQ), robustness, and stability. To validate the reliability and feasibility of the (19)F-NMR technology in quantitative analysis of pharmaceutical analytes, the assay result has been compared with that of (1)H-NMR. The statistical F-test and student t-test at 95% confidence level indicate that there is no significant difference between these two methods. Due to the advantages of (19)F-NMR, such as higher resolution and suitability for biological samples, it can be used as a universal technology for the quantitative analysis of other fluorine-containing pharmaceuticals and analytes.


Asunto(s)
Pirazinas/análisis , Triazoles/análisis , Flúor/química , Espectroscopía de Resonancia Magnética , Fosfato de Sitagliptina
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