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1.
ACS Appl Bio Mater ; 7(1): 306-314, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38091496

RESUMO

Isolating cancer cells from tissues and providing an appropriate culture environment are important for a better understanding of cancer behavior. Although various three-dimensional (3D) cell culture systems have been developed, techniques for collecting high-purity spheroids without strong stimulation are required. Herein, we report a 3D cell culture system for the isolation of cancer spheroids using enzymatically synthesized cellulose oligomers (COs) and demonstrate that this system isolates only cancer spheroids under coculture conditions with normal cells. CO suspensions in a serum-containing cell culture medium were prepared to suspend cells without settling. High-purity cancer spheroids could be separated by filtration without strong stimulation because the COs exhibited antibiofouling properties and a viscosity comparable to that of the culture medium. When human hepatocellular carcinoma (HepG2) cells, a model for cancer cells, were cultured in the CO suspensions, they proliferated clonally and efficiently with time. In addition, only developed cancer spheroids from HepG2 cells were collected in the presence of normal cells by using a mesh filter with an appropriate pore size. These results indicate that this approach has potential applications in basic cancer research and cancer drug screening.


Assuntos
Neoplasias Hepáticas , Esferoides Celulares , Humanos , Celulose , Técnicas de Cocultura , Células Hep G2
2.
Biomater Sci ; 10(10): 2665-2672, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35420601

RESUMO

Radiation therapy is a powerful approach for cancer treatment due to its low invasiveness. The development of radiation sensitizers is of great importance as they assist in providing radiation therapy at a low dose. In this study, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-modified gold nanocomposites of different shapes were created using the grafting-to approach to serve as a novel radiation sensitizer with high cellular uptake. The effect of the shape of the nanocomposite on cellular uptake by the breast cancer cell line MCF-7 was also investigated. The PMPC-modified gold nanostars showed the highest cellular uptake compared to the other gold nanocomposites (spheres and rods), whereas cell cytotoxicity was negligible among all candidates. Furthermore, the therapeutic effect of radiation of PMPC-modified nanostars was the highest among all the gold nanocomposites. These results clearly indicate that the shape of the gold nanocomposite is an important parameter for cellular uptake and radiation sensitizing effects in breast cancer cells.


Assuntos
Neoplasias da Mama , Nanocompostos , Radiossensibilizantes , Neoplasias da Mama/radioterapia , Feminino , Ouro , Humanos , Fosforilcolina/farmacologia , Polímeros , Ácidos Polimetacrílicos
3.
ACS Appl Mater Interfaces ; 14(14): 16074-16081, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35353480

RESUMO

Regulation of nanomaterial-cell interaction is an important requisite for a variety of biomedical applications such as drug delivery systems and theranostics. Here, we demonstrate the regulation of nanomaterial-cell interaction using the oriented adsorption of intrinsic immunoglobulin G (IgG) on molecularly imprinted polymer nanogels (MIP-NGs) capable of recognizing the fragment crystallizable (Fc) domain of IgG. The unique domain recognition property resulted in the suppression of the immune response in Fc domain receptor-possessing macrophages and natural killer cells due to the regulation of protein corona based on the oriented adsorption of IgG. This resulted in the hindrance of the Fc domain, which is the trigger of an immune response. Furthermore, the acquisition of stealth capability was successfully demonstrated in vivo using intravital confocal laser scanning microscopy. The domain imprinting proposed in this study will provide a new strategy for creating nanomaterials capable of domain recognition-based oriented adsorption of intrinsic proteins in situ, thus regulating the protein corona formed on the nanomaterials. Thus, the unique Fc domain-recognition nanomaterial developed in our study can be used for various biomedical applications to target specific cells without triggering an immune response.


Assuntos
Impressão Molecular , Coroa de Proteína , Adsorção , Imunoglobulina G , Impressão Molecular/métodos , Nanogéis
4.
Langmuir ; 36(36): 10674-10682, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32794751

RESUMO

Nanomaterials have become increasingly promising for biomedical applications owing to their specific biological characteristics. As drug delivery vehicles, nanomaterials have to circulate in the bloodstream to deliver the encapsulated components to the target tissues. Protein corona regulation is one of the promising approaches that gives stealth capability to avoid immune response. The aim of this study was to develop molecularly imprinted polymer nanogels (MIP-NGs) capable of protein corona regulation, using intrinsic human serum albumin (HSA) and with a functional monomer, dansylamide ethyl acrylamide (DAEAm), the dansylamide group serving as a ligand for HSA. The recognition capability of HSA for MIP-NGs was investigated by isothermal titration calorimetry (ITC). The affinity of the MIP-NGs prepared with DAEAm was then compared to that of the reference MIP-NGs prepared with pyrrolidyl acrylate developed in our previous study. Furthermore, we demonstrated that the concurrent use of these two different functional monomers for molecular imprinting was further effective to construct high-affinity recognition nanocavities for HSA and to form HSA-rich protein corona in the human plasma owing to the different interaction modes of the monomers. We believe that the molecular imprinting strategy developed through the use of ligand-based functional monomer is an effective strategy to create artificial molecular recognition materials.


Assuntos
Impressão Molecular , Coroa de Proteína , Compostos de Dansil , Humanos , Nanogéis , Albumina Sérica Humana
5.
Anal Chem ; 92(9): 6401-6407, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32282196

RESUMO

Accurate, simple, and valuable analytical methods for detection of food contamination are rapidly expanding to evaluate the validity of food product quality because of ethnic considerations and food safety. Herein molecularly imprinted nanogels (MIP-NGs), capable of porcine serum albumin (PSA) recognition, were prepared as artificial molecular recognition elements. The MIP-NGs were immobilized on a quartz crystal microbalance (QCM) sensor for detection of pork contamination in real beef extract samples. The MIP-NGs-based QCM sensor showed high affinity and excellent selectivity toward PSA compared to reference serum albumins from five different animals. The high PSA specificity of MIP-NGs led to the detection of pork contamination with a detection limit of 1% (v/v) in real beef extract samples. We believe the artificial molecular recognition materials prepared by molecular imprinting are a promising candidate for halal food control.


Assuntos
Contaminação de Alimentos/análise , Carne/análise , Impressão Molecular , Nanogéis/química , Albumina Sérica/análise , Animais , Bovinos , Técnicas de Microbalança de Cristal de Quartzo , Suínos
6.
Mech Dev ; 139: 1-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26868000

RESUMO

Ppp6c, which encodes the catalytic subunit of phosphoprotein phosphatase 6 (PP6), is conserved among eukaryotes from yeast to humans. In mammalian cells, PP6 targets IκBε for degradation, activates DNA-dependent protein kinase to trigger DNA repair, and is reportedly required for normal mitosis. Recently, Ppp6c mutations were identified as candidate drivers of melanoma and skin cancer. Nonetheless, little is known about the physiological role of Ppp6c. To investigate this function in vivo, we established mice lacking the Ppp6c phosphatase domain by crossing heterozygous mutants. No viable homozygous pups were born, indicative of a lethal mutation. Ppp6c homozygous mutant embryos were identified among blastocysts, which exhibited a normal appearance, but embryos degenerated by E7.5 and showed clear developmental defects at E8.5, suggesting that mutant embryos die after implantation. Accordingly, homozygous blastocysts showed significant growth failure of the inner cell mass (ICM) in in vitro blastocyst culture, and primary Ppp6c exon4-deficient MEFs showed greatly reduced proliferation. These results establish for the first time that the Ppp6c phosphatase domain is indispensable for mouse embryogenesis after implantation.


Assuntos
Fosfoproteínas Fosfatases/fisiologia , Animais , Blastocisto/citologia , Blastocisto/enzimologia , Proliferação de Células , Células Cultivadas , Técnicas de Cultura Embrionária , Implantação do Embrião , Desenvolvimento Embrionário , Éxons , Feminino , Genes Letais , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Deleção de Sequência
7.
FEBS Lett ; 589(19 Pt B): 2754-62, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26296315

RESUMO

In mammals, the small Arf GTPase-activating protein (SMAP) subfamily of Arf GTPase-activating proteins consists of closely related members, SMAP1 and SMAP2. These factors reportedly exert distinct functions in membrane trafficking, as manifested by different phenotypes seen in single knockout mice. The present study investigated whether SMAP proteins interact genetically. We report for the first time that simultaneous loss of SMAP1 and SMAP2 promotes apoptosis in the distal region of E7.5 mouse embryos, likely resulting in embryonic lethality. Thus, at least one SMAP gene, either SMAP1 or SMAP2, is required for proper embryogenesis.


Assuntos
Embrião de Mamíferos/embriologia , Proteínas de Membrana/deficiência , Proteínas de Membrana/metabolismo , Animais , Apoptose , Linhagem Celular , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Endocitose , Humanos , Proteínas de Membrana/genética , Camundongos , Transporte Proteico , Deleção de Sequência , Transferrina/metabolismo
8.
Biochem Biophys Res Commun ; 453(4): 748-53, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25305484

RESUMO

ADP-ribosylation factor (Arf) 1 is thought to affect the morphologies of organelles, such as the Golgi apparatus, and regulate protein trafficking pathways. Mice have six Arf isoforms. In knockdown experiments with HeLa cells, no single Arf isoform among Arf1-5 is required for organelle morphologies or any membrane trafficking step. This suggests that the cooperation of two or more Arfs is a general feature. Although many cell biological and biochemical analyses have proven the importance of Arf1, the physiological roles of Arf1 in mice remain unknown. To investigate the activity of Arf1 in vivo, we established Arf1-deficient mice. Arf(-/-) blastocysts were identified at the expected Mendelian ratio. The appearance of these blastocysts was indistinguishable from that of wild-type and Arf(+/-) blastocysts, and they grew normally in an in vitro culture system. However, Arf(-/-) embryos were degenerated at E5.5, and none survived to E12.5, suggesting that they died soon after implantation. These data establish for the first time that the Arf1 gene is indispensable for mouse embryonic development after implantation.


Assuntos
Fator 1 de Ribosilação do ADP/metabolismo , Implantação do Embrião/fisiologia , Embrião de Mamíferos/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Animais , Desenvolvimento Embrionário , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
10.
Int Ophthalmol ; 34(4): 805-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24234424

RESUMO

To investigate differences between preoperative target refraction and postoperative spherical equivalent refraction in eyes with the first attack of acute angle closure glaucoma before and after surgery. We retrospectively examined eyes of 36 patients who suffered the first attack of acute primary angle closure after undergoing cataract extraction and intraocular lens implant. We measured keratometric values (K1, K2) due to medical therapy for high ocular tension and the mean time interval until surgery. We compared the axial length, expected diopter, logMAR visual acuity, K1, K2, refractive spherical equivalent, and intraocular pressure (IOP) before and 6 months after surgery. The average preoperative IOP was 51.3 ± 9.0 mmHg, but it decreased to 14.8 ± 3.6 mmHg after surgery. No corneal edema was observed after surgery. The average axial length was 22.12 ± 1.03 mm and there was no significant change in keratometric values, which were 7.72 ± 0.33 mm (K1) and 7.51 ± 0.31 mm (K2) before surgery and 7.67 ± 0.33 mm (K1) and 7.49 ± 0.29 mm (K2) after surgery. Similarly, no significant difference was observed in average preoperative target refractive error (-0.57 ± 0.53 D) and average postoperative refractive spherical equivalent (-0.67 ± 0.97 D). The inability to accurately determine preoperative refractive error due to corneal edema or other complications is a concern during the first attack of acute angle closure glaucoma. However, our results indicate that no differences should be expected between preoperative refractive error and postoperative refractive spherical equivalent.


Assuntos
Extração de Catarata , Glaucoma de Ângulo Fechado/cirurgia , Complicações Pós-Operatórias/fisiopatologia , Erros de Refração/fisiopatologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Comprimento Axial do Olho , Feminino , Glaucoma de Ângulo Fechado/fisiopatologia , Humanos , Pressão Intraocular/fisiologia , Implante de Lente Intraocular , Masculino , Estudos Retrospectivos , Acuidade Visual/fisiologia
11.
Case Rep Ophthalmol ; 4(3): 134-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24163681

RESUMO

BACKGROUND: Cases of cataract surgery without penetrating keratoplasty in patients with Peters' anomaly are very rare. We report a case of Peters' anomaly type 2 with tilted lens due to synechia between the lens and iris that was treated with cataract surgery without penetrating keratoplasty. CASE PRESENTATION: A 16-year-old girl had Peters' anomaly in both eyes. Corneal opacity was severe in the left eye due to high-grade dysgenesis of the anterior segment. In the right eye, corneal opacity had spread from the center of the cornea to the inferotemporal side, and there was synechia between the iris and corneal endothelium from the inferonasal side to the inferotemporal side. Opacity was observed in the anterior pole of the lens, and there was synechia between the anterior iris and the lens. Ultrasound biomicroscopy (UBM) revealed that the lens was tilted because of synechia. The tilted lens induced astigmatism, which reduced visual acuity to 20/250, in conjunction with a cataract. Cataract surgery was performed; the synechia between the lens capsule and the iris was severed, an intraocular lens was inserted, and the tilt was repaired. UBM was used postoperatively to confirm that the lens capsule synechia had been corrected and that the intraocular lens was not tilted. As a result, visual acuity improved to 20/100; glaucoma and expansion of corneal opacity were not observed. CONCLUSIONS: Severing of the synechia between the cataract and iris, during cataract surgery, in a patient with Peters' anomaly type 2 resulted in favorable postoperative visual acuity.

12.
Graefes Arch Clin Exp Ophthalmol ; 251(10): 2415-20, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23864437

RESUMO

BACKGROUND: To evaluate changes in retinal and choroidal thickness changes after three intravitreal ranibizumab (IVR) injections for polypoidal choroidal vasculopathy (PCV) using enhanced depth-imaging-optical coherence tomography (EDI-OCT). METHODS: In this retrospective, observational case series, EDI-OCT was used to measure changes in choroidal thickness at nine points in a lattice shape in the macula before and after introductory-stage IVR. RESULTS: Choroidal thickness was decreased at all nine points in the lattice shape, but was significantly decreased only at the fovea. CONCLUSION: The subfoveal choroidal thickness may be reduced by introductory-stage IVR in patients with PCV. In particular, choroidal thickness at the fovea was reduced during the early stage of treatment.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Corioide/efeitos dos fármacos , Neovascularização de Coroide/tratamento farmacológico , Pólipos/tratamento farmacológico , Idoso , Corioide/patologia , Neovascularização de Coroide/diagnóstico , Feminino , Angiofluoresceinografia , Humanos , Injeções Intravítreas , Macula Lutea , Masculino , Pólipos/diagnóstico , Ranibizumab , Estudos Retrospectivos , Tomografia de Coerência Óptica
13.
Eur J Ophthalmol ; 23(5): 718-22, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23483506

RESUMO

OBJECTIVE: Globe rupture is a serious condition. Despite advancements in vitrectomy, the postoperative prognosis for visual acuity remains poor in many cases. We conducted multiple regression analysis to identify preoperative factors associated with postoperative visual acuity. 
 METHODS: Subjects comprised 24 patients with globe rupture in one eye who had 5 consecutive years of consultation and were followed up for 12 months or longer. Subjects comprised 13 males and 11 females with a mean age of 67.8 ± 17.4 years. Our methods involved performing multiple regression analysis with age, preoperative visual acuity, scope of injury, number of surgeries, hyphema, vitreous hemorrhage, retinal detachment, and subchoroidal hemorrhage as explanatory variables, and postoperative visual acuity as the response variable. 
 RESULTS: Preoperative visual acuity and scope of retinal detachment were explanatory factors found to correlate significantly with postoperative visual acuity after globe rupture. 
 CONCLUSIONS: Our results demonstrate that postoperative visual acuity can be predicted to some degree by preoperative visual acuity and the scope of retinal detachment.


Assuntos
Traumatismos Oculares/fisiopatologia , Acuidade Visual/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Traumatismos Oculares/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Período Pré-Operatório , Análise de Regressão , Descolamento Retiniano/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Ruptura , Vitrectomia
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