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1.
Transl Vis Sci Technol ; 6(6): 5, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29134136

RESUMEN

PURPOSE: We hypothesized that the elastic nature of the choroid leads to tissue contraction following a full-thickness, sharp incision. Furthermore, we sought to quantify, measure, and compare tissue contraction in ex vivo porcine globes and human globes of various ages using predetermined variables. METHOD: A full-thickness, ex vivo choroidal incision was performed in either pig (n = 97) or human (n = 30) specimens. Variables included trephine diameter (1.5, 2.0, or 2.5 mm) versus a straight surgical blade, and temperature (1.7 °-4.4° vs. 36.6°F). Central centripetal and surround centrifugal tissue contractions were measured. Mean percentage tissue contraction was assessed as a ratio of trephine diameter to final tissue contraction measured immediately following each incision using a standardized device. RESULTS: For trephination in pig specimens, centripetal contraction ranged from 38% to 50% with a mean of 44%. Centrifugal contraction was approximately 15%. Human choroidal contraction was 39% and 15%, respectively, with a statistically significant inverse relationship to age (R2 = 0.35, P ≤ 0.01). Asymmetric contraction was noted when incisions were closer to choroidal attachment sites to the sclera, such as near vortex ampullae. Linear incisions resulted in contraction that correlated with incision length (R2 = 0.35, P ≤ 0.001). CONCLUSIONS: A full-thickness choroidal incision results in significant tissue contraction. For circular incisions, the centripetal contraction approaches 50% of the original incision size. For linear incisions, the contraction corresponds directly with incision length. In human specimens, there is less contraction with advancing age. TRANSLATIONAL RELEVANCE: Our findings have clinical relevance for choroidal biopsy, traumatic injury, and choroidal translocation surgery.

2.
J Cosmet Sci ; 65(3): 175-86, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25043488

RESUMEN

In order to investigate potent whitening agents, we synthesized 15 cyclohexane diester derivatives and 15 benzene diester derivatives. To evaluate their structure-cytotoxicity relationships, we performed cell cytotoxicity tests on B16F10 mouse melanoma cells. To understand their whitening effects, melanin synthesis inhibitory activities in B16F10 cells and mushroom tyrosinase inhibitory activities were performed. In most cases, cell cytotoxicity was observed to be lower in 1,3-diester than in 1,2- and 1,4-diesters; when it came to the structural isomer of the side chain, all derivatives except the 1,2-cyclohexane diester derivatives showed lower cell cytotoxicity in the branch type of the side chain than in the linear type. Among the compounds evaluated, the compounds cyclohexane-1,3-diyl bis(decanoate), cyclohexane-1,4-diyl dioctanoate, and 1,3-phenylene bis (2-ethylhexanoate) emerged as potent melanin synthesis inhibitors. Our goal was to determine the expression levels of proteins involved in melanogenesis, Western blotting and RT-PCR showing that these compounds decreased tyrosinase, TRP-1, and TRP-2 while demonstrating significantly low cytotoxicity.


Asunto(s)
Benceno/efectos adversos , Ciclohexanos/efectos adversos , Ciclohexanos/química , Ésteres/efectos adversos , Melaninas/biosíntesis , Melanoma Experimental/patología , Preparaciones para Aclaramiento de la Piel/efectos adversos , Preparaciones para Aclaramiento de la Piel/química , Agaricales/enzimología , Animales , Benceno/síntesis química , Benceno/química , Benceno/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclohexanos/síntesis química , Ciclohexanos/toxicidad , Citotoxinas/toxicidad , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/toxicidad , Ésteres/síntesis química , Ésteres/química , Ésteres/toxicidad , Melaninas/antagonistas & inhibidores , Melanoma Experimental/inducido químicamente , Ratones , Modelos Moleculares , Estructura Molecular , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Preparaciones para Aclaramiento de la Piel/síntesis química , Preparaciones para Aclaramiento de la Piel/toxicidad , Relación Estructura-Actividad , Pruebas de Toxicidad
3.
Nanoscale Res Lett ; 6: 528, 2011 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-21943314

RESUMEN

Cytotoxicity is a severe problem for cadmium sulfide nanoparticles (CSNPs) in biological systems. In this study, mercaptoacetic acid-coated CSNPs, typical semiconductor Q-dots, were synthesized in aqueous medium by the arrested precipitation method. Then, amino-terminated polyethylene glycol (PEG) was conjugated to the surface of CSNPs (PCSNPs) in order to introduce amino groups to the surface. Finally, insulin was immobilized on the surface of PCSNPs (ICSNPs) to reduce cytotoxicity as well as to enhance cell compatibility. The presence of insulin on the surface of ICSNPs was confirmed by observing infrared absorptions of amide I and II. The mean diameter of ICSNPs as determined by dynamic light scattering was about 38 nm. Human fibroblasts were cultured in the absence and presence of cadmium sulfide nanoparticles to evaluate cytotoxicity and cell compatibility. The results showed that the cytotoxicity of insulin-immobilized cadmium sulfide nanoparticles was significantly suppressed by usage of PEG as a spacer. In addition, cell proliferation was highly facilitated by the addition of ICSNPs. The ICSNPs used in this study will be potentials to be used in bio-imaging applications.

4.
Biomacromolecules ; 11(5): 1248-53, 2010 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-20415469

RESUMEN

Infections with bacteria have become a serious problem in joint arthroplasty. This study reports about in vitro antibacterial activity and in vitro cell compatibility of poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers loaded with metallic silver particles of a size of 5-13 nm. In vitro antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae was studied by microplate proliferation tests. The adhesion, viability, and proliferation properties of fibroblasts (NIH 3T3) and differentiation of osteoblasts (MC3T3-E1) were done to study in vitro cell compatibility of the scaffolds. As the results, only silver-containing PHBV nanofibrous scaffolds showed a high antibacterial activity and an inhibitory effect on the growth of both Staphylococcus aureus and Klebsiella pneumoniae bacteria. The nanofibrous scaffolds having silver nanoparticles <1.0% were free of in vitro cytotoxicity. To sum up, the PHBV nanofibrous scaffolds having nanoparticles <1.0 wt % showed not only good antibacterial activity but also good in vitro cell compatibility. It is considered that the PHBV nanofibrous scaffolds with silver nanoparticles <1.0 wt % have a potential to be used in joint arthroplasty.


Asunto(s)
Antibacterianos/farmacología , Materiales Biocompatibles , Nanoestructuras , Plata/química , Ingeniería de Tejidos , Animales , Klebsiella pneumoniae/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Células 3T3 NIH , Staphylococcus aureus/efectos de los fármacos
5.
Arch Pharm Res ; 25(6): 801-6, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12510829

RESUMEN

Cyclicpeptides are important targets in peptide synthesis because of their interesting biological properties. Constraining highly flexible linear peptides by cyclization is one of the mostly widely used approaches to define the bioactive conformation of peptides. Cyclic peptides often have increased receptor affinity and metabolic stability over their linear counterparts. We carried out virtual screening experiment via docking in order to understand the interaction between HLE-Human Leukocyte Elastase and ligand peptide and to identify the sequence that can be a target in various ligand peptides. We made cyclic peptides as a target base on Met-Ile-Phe sequence having affinity for ligand and receptor active site docking. There are three ways to cyclize certain sequences of amino acids such as Met-Ile-Phe-Gly-Ile. First is head-to-tail cyclization method, linking between N-terminal and C-terminal. Second method utilizes amino acid side chain such as thiol functional group in Cys, making a thioether bond. The last one includes an application of resin-substituted amino acids in solid phase reaction. Among the three methods, solid phase reaction showed the greatest yield. Macrocyclization of Fmoc-Met-Ile-Phe-Gly-Ile-OBn after cleavage of Fmoc protection in solution phase was carried out to give macrocyclic compound 5 in about 7% yield. In the contrast with solution phase reaction, solid phase reaction for macrocyclization of Met-Ile-Phe-Gly-Ile-Asp-Tentagel in normal concentrated condition gave macrocyclic compound 7 in more than 35% yield.


Asunto(s)
Péptidos Cíclicos/síntesis química , Tecnología Farmacéutica/métodos , Ciclización
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