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1.
Ecotoxicol Environ Saf ; 281: 116652, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941657

RESUMO

Microalgal growth-based tests are international standards for ecotoxicity assessment; however, their long exposure times, large sample volumes, and reliance on a single growth-endpoint make them inadequate for rapid toxicity screening. Here, we aimed to develop a rapid and simple ecotoxicological test using the fast-growing green alga Mychonastes afer, with multiple endpoints-growth, lipid content, and photosynthesis. We exposed M. afer to two metals-silver and copper-and two herbicides-atrazine and diuron-for 24 h and identified the most sensitive and reliable endpoints for each toxicant: the maximum electron transport rate (ETRmax) for Ag, Cu and atrazine, and the lipid content for diuron. Lipid content was found to be both a sensitive and reliable biomarker, meeting the effluent limit guidelines in both the Republic of Korea and the USA. The sensitivity of M. afer to Ag and atrazine also closely matched the HC5 values derived from the species sensitivity distribution approach, confirming its reliability for setting regulatory concentrations of these contaminants. Our calculated predicted no-effect concentration (PNEC) values were similar to established European Union PNECs for Ag, Cu, atrazine, and diuron, underlining the utility of these biological endpoints for ecological risk assessment and regulatory decision making. This method required lower sample volume (2 mL vs 100 mL) and exposure time (24 h vs 72-120 h) than conventional green algal tests, and eliminated the need for labour-intensive cell counting, expensive equipment, and chlorophyll fluorescence measurement expertise. Overall, this M. afer test can be a valuable tool for the rapid screening of wastewater for metals and herbicides, contributing to environmental protection and management practices.


Assuntos
Atrazina , Cobre , Diurona , Ecotoxicologia , Herbicidas , Testes de Toxicidade , Poluentes Químicos da Água , Herbicidas/toxicidade , Diurona/toxicidade , Atrazina/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Testes de Toxicidade/métodos , Cobre/toxicidade , Ecotoxicologia/métodos , Fotossíntese/efeitos dos fármacos , Prata/toxicidade , República da Coreia , Haptófitas/efeitos dos fármacos , Monitoramento Ambiental/métodos , Clorófitas/efeitos dos fármacos
2.
Int Ophthalmol ; 44(1): 179, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38622479

RESUMO

PURPOSE: To evaluate the clinical outcomes of intravenous tocilizumab (TCZ) injection in patients with moderate-to-severe active thyroid eye disease (TED). METHODS: Patients with active and moderate-to-severe TED who did not respond to conventional therapies were treated with TCZ from June 2019 to January 2021. The medical records of the patients were evaluated before the treatment. We analyzed patient demographics, including the duration of Graves' disease and TED, and assessed subjective symptoms, such as diplopia and ocular movement, clinical activity score (CAS), modified NOSPECS score, and exophthalmos before treatment and at 4, 8, 12, and 16 weeks after the first drug injection. Blood tests, including TSH Rc Ab and TS Ab, were performed before treatment and 24 weeks after the first injection. And orbital computed tomography (CT) was performed and Barrett's Index was calculated at baseline and after completion of all injections. RESULTS: Nineteen completed the scheduled treatment. There were no significant side effects, other than herpes zoster in one case and headache and dermatitis in another. Clinical symptoms before and 16 weeks after the treatment showed mean CAS decreased by 2.4 points, mean modified NOSPECS score decreased by 3.7 points, and mean exophthalmos decreased by 0.4 mm. Diplopia and extraocular muscle limitation improved in ten and remained stationary in five of the 15 patients, who presented with extraocular motility abnormalities. Six of 11 patients who underwent orbit CT showed improvement in muscle size. The mean TSH Rc Ab decreased by 7.5 IU/L and TS-Ab decreased by 162.9%. CONCLUSION: TCZ can treat active moderate-to-severe TED, showing high drug compliance and reasonable response to inflammation and extraocular motility abnormality.


Assuntos
Anticorpos Monoclonais Humanizados , Exoftalmia , Oftalmopatia de Graves , Humanos , Oftalmopatia de Graves/diagnóstico , Oftalmopatia de Graves/tratamento farmacológico , Estudos Prospectivos , Diplopia/etiologia , Corticosteroides/uso terapêutico , Tireotropina
3.
Graefes Arch Clin Exp Ophthalmol ; 261(7): 2019-2029, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36680611

RESUMO

PURPOSE: This study aimed to assess the association between hormone replacement therapy (HRT) and the prevalence of nonarteritic anterior ischemic optic neuropathy (NAION) in menopausal women using national data from the entire Korean population. METHODS: The health screening data of 1,381,605 women between 40 and 90 years of age collected by the National Health Insurance Service (NHIS) of Korea between January 1, 2009, and December 31, 2018, were retrospectively reviewed. Before data analysis, the potential cofounders were adjusted for among all participants. Based on HRT use and its duration (classified into four groups), the hazard ratio (HR) and 95% confidence interval (CI) of NAION development were calculated via a Cox proportional hazards regression analysis using the nonuser group as a reference. RESULTS: Overall, 7824 NAION diagnoses were made during the mean follow-up of 8.22 years (standard deviation: 1.09 years) in 1,381,605 post-menopausal women. NAION was more common in the HRT group than in the non-HRT group (HR [95% CI]: 1.268 [1.197-1.344]). Furthermore, the risk of NAION increased along with increased HRT duration (p < 0.0001). In the multivariate analysis, the adjusted HRs of the < 2-year HRT group, the 2-5-year HRT group, and the ≥ 5-year HRT group were 1.19 (95% CI: 1.10-1.28), 1.3 (95% CI: 1.17-1.45), and 1.473 (95% CI: 1.31-1.65), respectively. Compared to women younger than 65 years, the HR of HRT for NAION was significantly higher than that of women older than 65 years (p < 0.0001). CONCLUSION: Our population-based cohort study found that HRT was significantly associated with increased incidence of NAION. The incidence of NAION also increased with the duration of HRT.


Assuntos
Arterite , Neuropatia Óptica Isquêmica , Humanos , Feminino , Estudos de Coortes , Estudos Retrospectivos , Neuropatia Óptica Isquêmica/diagnóstico , Incidência , Arterite/complicações , Arterite/diagnóstico , Arterite/epidemiologia , Fatores de Risco , Terapia de Reposição Hormonal/efeitos adversos
4.
BMC Ophthalmol ; 20(1): 195, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32423393

RESUMO

BACKGROUND: Leber's hereditary optic neuropathy (LHON) is a maternally inherited mitochondrial disease, characterized by acute or subacute, painless, bilateral visual loss. LHON is often misdiagnosed as optic neuritis at an early stage because of the similarity of their clinical presentation. To date, there has been no reported case of actual optic neuritis and LHON in one patient. CASE PRESENTATION: A 40-year-old, healthy man was referred to our clinic with acute painful visual loss in the right eye for 2 weeks. In the right eye, visual acuity decreased to 20/40, and the Ishihara colour test score was 8/14 with a relative afferent pupillary defect. Optic disc swelling was found only in the right eye, and magnetic resonance imaging revealed enhancement of the the right optic nerve, consistent with optic neuritis. After receiving 1 g of intravenous methylprednisolone daily for three days, his ocular pain resolved, and visual acuity improved to 20/20 within 2 weeks. Seven months later, the patient developed acute painless visual loss in the right eye. Visual acuity decreased to 20/200 in the right eye. There was no response to the intravenous methylprednisolone therapy at that time. Eight months later, he developed subacute painless visual loss in the left eye. Genetic testing for LHON was performed and revealed the pathologic mtDNA 11778 point mutation. CONCLUSIONS: We report a case with painful unilateral optic neuritis preceding the onset of LHON. Even if a typical optic neuritis patient has completely recovered from steroid treatment once in the past, it is advisable to keep in mind the possibility of LHON if acute or subacute loss of vision subsequently or simultaneously occurs in both eyes and does not respond to steroids.


Assuntos
Atrofia Óptica Hereditária de Leber/etiologia , Nervo Óptico/diagnóstico por imagem , Neurite Óptica/complicações , Acuidade Visual , Adulto , DNA/análise , Análise Mutacional de DNA , Humanos , Imageamento por Ressonância Magnética , Masculino , Atrofia Óptica Hereditária de Leber/diagnóstico , Atrofia Óptica Hereditária de Leber/genética , Neurite Óptica/diagnóstico , Mutação Puntual
5.
Biomacromolecules ; 19(11): 4219-4227, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30265806

RESUMO

Protein nanocapsules are potentially useful as functional nanocarriers because of their hollow structure and high biocompatibility and the intrinsic activity of their protein constituents. However, the development of a facile method for the preparation of oriented nanocapsules that retain their protein activity has been challenging. Here we describe the preparation of protein nanocapsules through the enzymatic removal of polymer templates. Nickel(II) nitrilotriacetic acid-end-functionalized poly(lactic acid) (Ni2+-NTA-PLA) was introduced as a polymeric template to immobilize hexa-histidine-tagged green fluorescence protein (His6-GFP) with consistent orientation. Following protein cross-linking and core-degradation, various measurements as a function of degradation time indicated the formation of hollow structures. We also demonstrated orientational control and activity preservation of the protein after capsule preparation. Protein nanocapsules prepared by this method can act as functional containers, taking advantage of the intrinsic function of their constituent proteins without additional modification.


Assuntos
Proteínas de Fluorescência Verde/metabolismo , Histidina/química , Proteínas Imobilizadas/metabolismo , Nanocápsulas/química , Níquel/química , Ácido Nitrilotriacético/química , Polímeros/química , Proteínas de Fluorescência Verde/química , Proteínas Imobilizadas/química , Propriedades de Superfície
8.
Int J Biol Macromol ; 262(Pt 2): 130240, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368993

RESUMO

This study aimed to enhance the thermal stability of microporous separators by introducing cellulose propionate (CP) as an innovative polymer matrix material, supplemented with glycerin as an additive. CP/glycerin composite membranes were created using hydraulic pressure techniques to reinforce essential separator properties. SEM analysis unveiled interconnected pores crucial for efficient ion transport, initiating water flux measurements at 5 bar. These measurements showcased improved mechanical strength, resulting in a porosity of 74.1 %. FT-IR spectroscopy illustrated CP-glycerin interactions, inducing plasticization and facilitating pore formation. Thermal Gravimetric Analysis (TGA) demonstrated superior thermal stability in CP/glycerin composite membranes compared to cellulose acetate (CA). Differential Scanning Calorimetry (DSC) revealed a slight reduction in thermal stability within a specific temperature range due to glycerin-induced plasticization effects. Nonetheless, the melting temperature (Tm) of CP/glycerin membranes increased to 188.4 °C, indicating heightened stability at elevated temperatures. Despite pressure-induced pore formation, CP/glycerin membranes exhibited enhanced thermal stability, suggesting reinforced molecular interactions. Overall, this study introduces a novel CP/glycerin composite membrane featuring improved thermal stability, enhanced strength, and controlled pore structures essential for efficient lithium-ion battery applications.


Assuntos
Glicerol , Propionatos , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Celulose/química
9.
Int J Biol Macromol ; 263(Pt 1): 130243, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38378111

RESUMO

This study investigates the influence of citric acid concentration on the fabrication of porous cellulose acetate (CA) membranes using the Non-Solvent Induced Phase Separation (NIPS) method. A notable aspect is the precise control over membrane properties, particularly pore size and porosity, achieved solely through the adjustment of citric acid concentration, serving as the additive. Higher concentrations of citric acid increase pore size by rendering polymer chains more pliable, whereas lower concentrations lead to smaller, denser pores due to improved dispersion in the CA matrix and altered water interactions during phase separation. A decrease in porosity and Gurley values with reducing citric acid concentrations (from 5 × 10-2 to 1 × 10-3 M ratios) indicates less plasticization of CA chains. However, at very low concentrations (1 × 10-4 and 1 × 10-5), porosity increases, despite the presence of smaller pores, and Gurley values approach those of pure CA in terms of gas permeability. Fourier Transform Infrared (FT-IR) spectroscopy confirms the presence of citric acid and its interaction with carbonyl groups, consistent with the pore size observations from Scanning Electron Microscopy (SEM). Spectral data deconvolution reveals weakened carbonyl bonds due to the reduced presence of citric acid, correlating with the smaller pores observed in SEM. Thermal Gravimetric Analysis (TGA) demonstrates that composite membranes are more thermally stable than pure CA, attributed to the citric acid-induced crosslinking within the polymer chains. Stability increases with decreasing citric acid concentration, with some anomalies at the lowest levels. In conclusion, this study highlights the capability of adjusting citric acid concentration to tailor membrane properties, offering valuable insights for the creation of porous materials across diverse industrial applications.


Assuntos
Celulose , Celulose/análogos & derivados , Polímeros , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Celulose/química
10.
Commun Biol ; 7(1): 115, 2024 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245624

RESUMO

A critical requirement for studying cell mechanics is three-dimensional assessment of cellular shapes and forces with high spatiotemporal resolution. Traction force microscopy with fluorescence imaging enables the measurement of cellular forces, but it is limited by photobleaching and a slow acquisition speed. Here, we present refractive-index traction force microscopy (RI-TFM), which simultaneously quantifies the volumetric morphology and traction force of cells using a high-speed illumination scheme with 0.5-Hz temporal resolution. Without labelling, our method enables quantitative analyses of dry-mass distributions and shear (in-plane) and normal (out-of-plane) tractions of single cells on the extracellular matrix. When combined with a constrained total variation-based deconvolution algorithm, it provides 0.55-Pa shear and 1.59-Pa normal traction sensitivity for a 1-kPa hydrogel substrate. We demonstrate its utility by assessing the effects of compromised intracellular stress and capturing the rapid dynamics of cellular junction formation in the spatiotemporal changes in non-planar traction components.


Assuntos
Fenômenos Mecânicos , Tração , Microscopia de Força Atômica/métodos , Algoritmos
11.
Exp Mol Med ; 55(2): 377-384, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36720917

RESUMO

Various CRISPR‒Cas9 orthologs are used in genome engineering. One of the smallest Cas9 orthologs is cjCas9 derived from Campylobacter jejuni, which is a highly specific genome editing tool. Here, we developed cjCas9-based base editors including a cytosine base editor (cjCBEmax) and an adenine base editor (cjABE8e) that can successfully induce endogenous base substitutions by up to 91.2% at the HPD gene in HEK293T cells. Analysis of the base editing efficiency of 13 endogenous target sites showed that the active windows of cjCBEmax and cjABE8e are wider than those of spCas9-based base editors and that their specificities are slightly lower than that of cjCas9. Importantly, engineered cjCas9 and gRNA scaffolds can improve the base editing efficiency of cjABE8e by up to 6.4-fold at the HIF1A gene in HEK293T cells. Due to its small size, cjABE8e can be packaged in a single adeno-associated virus vector with two tandem arrays of gRNAs, and the delivery of the resulting AAV could introduce base substitutions at endogenous ANGPT2 and HPD target sites. Overall, our findings have expanded the potential of the use of base editors for in vivo or ex vivo therapeutic approaches.


Assuntos
Campylobacter jejuni , Edição de Genes , Humanos , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Células HEK293 , RNA Guia de Sistemas CRISPR-Cas
12.
J Clin Med ; 12(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37892580

RESUMO

BACKGROUND: An advanced age and the female sex are widely recognized risk factors for both cataract and dementia. We investigated the effect of cataract surgery on the incidence of dementia in a Korean population aged ≥ 45 years with a previous diagnosis of cataract. METHODS: This nationwide cohort study was performed using Korean National Health Insurance Service data collected from 2006 to 2017. A total of 300,327 subjects aged ≥ 45 years with a history of cataract diagnosis but no previous diagnosis of dementia were analyzed. The relationship between cataract surgery and dementia was evaluated, applying a time-varying analysis to evaluate the hazard ratio (HR) and 95% confidence interval (CI) values according to dementia. It was calculated via a multivariable Cox regression model, with adjustments for age, sex, visual acuity (VA), ocular and systemic comorbidities, and social factors (including body mass index, income, smoking, and drinking). RESULTS: In the multivariate analysis, the cataract surgery group showed a marginal difference in dementia development (HR 1.10 [95% CI 1.02-1.19]) because both cataract and dementia share common risk factors. However, in the subgroup analysis, men (HR 0.49 [95% CI 0.26-0.90]) and patients under 65 years of age (HR 0.88 [95% CI 0.79-0.99]) in the group with cataract surgery and good VA showed a significantly lower incidence of dementia. CONCLUSION: Through visual improvement, together with timely surgical intervention, the procedure can alleviate the risk of dementia in visually impaired patients, especially in younger and male patients.

13.
Biomol Ther (Seoul) ; 31(2): 227-239, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36789738

RESUMO

Major depressive disorder is a leading cause of disability in more than 280 million people worldwide. Monoamine-based antidepressants are currently used to treat depression, but delays in treatment effects and lack of responses are major reasons for the need to develop faster and more efficient antidepressants. Studies show that ketamine (KET), a PCP analog, produces antidepressant effects within a few hours of administration that lasts up to a week. However, the use of KET has raised concerns about side effects, as well as the risk of abuse. 4 -F-PCP analog is a novel PCP analog that is also an NMDA receptor antagonist, structurally similar to KET, and might potentially elicit similar antidepressant effects, however, there has been no study on this subject yet. Herein, we investigate whether 4-F-PCP displays antidepressant effects and explored their potential therapeutic mechanisms. 4-F-PCP at 3 and 10 mg/kg doses showed antidepressant-like effects and repeated treatments maintained its effects. Furthermore, treatment with 4-F-PCP rescued the decreased expression of proteins most likely involved in depression and synaptic plasticity. Changes in the excitatory amino acid transporters (EAAT2, EAAT3, EAAT4) were also seen following drug treatment. Lastly, we assessed the possible side effects of 4-F-PCP after long-term treatment (up to 21 days). Results show that 4-F-PCP at 3 mg/kg dose did not alter the cognitive function of mice. Overall, current findings provide significant implications for future research not only with PCP analogs but also on the next generation of different types of antidepressants.

14.
Am J Ophthalmol Case Rep ; 27: 101592, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35642221

RESUMO

Purpose: We report the first case of neuroretinitis after administration of a second dose of a messenger RNA vaccine for coronavirus disease-2019 (COVID-19). Observations: An 83-year-old healthy woman presented with subacute, painless, and progressive visual loss in the right eye that started 2 days after the second injection of the COVID-19 vaccine (Comirnaty®) from Pfizer (New York, NY, USA) and BioNTech (Mainz, Germany). Visual acuities were hand motion perception in the right eye and 20/30 in the left eye. There was optic nerve head swelling in the right eye and subretinal fluid and disruption of the photoreceptor layers in both eyes. Magnetic resonance imaging revealed an enhancement of the right optic nerve, consistent with optic neuritis. She was treated with intravenous corticosteroids, and the optic nerve swelling in the right eye resolved promptly. However, the amount of subretinal fluid worsened for 1 month and did not improve until 6 months from onset. Her visual acuity was slightly improved to finger count perception in the right eye and 20/20 in the left eye during an examination 6 months from onset. Conclusions and Importance: Considering the temporal relation between the second dose of vaccination and the symptom onset in our patient, the ophthalmic symptoms here reported might be considered a rare adverse effect of the Comirnaty® COVID-19 vaccine. Although a causal relationship is not established, to our knowledge, this is the first report of neuroretinitis after vaccination with Comirnaty®, and any further similar cases should be examined in detail.

15.
Sci Rep ; 11(1): 21769, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741084

RESUMO

This study aimed to assess detection rate of telangiectatic capillaries (TelCaps) with infrared reflectance (IR) and optical coherence tomography (OCT) images and to evaluate the clinical efficacy of IR image-guided focal laser photocoagulation of TelCaps in persistent diabetic macular edema (DME). This retrospective case series included 28 eyes of 28 patients with TelCap and persistent DME refractory to intravitreal anti-vascular endothelial growth factor or corticosteroids. The presence of TelCaps was confirmed using IR and OCT images. All patients were followed up for more than 12 months after direct focal laser photocoagulation of the TelCaps. The TelCap closure rate, changes in best-corrected visual acuity, and central subfield thickness were analyzed. On IR imaging, TelCap appeared as a characteristic hyperreflectivity within a hyporeflective spherical lesion in 85.7% of the eyes. After focal laser photocoagulation, the TelCap closure rate was 57.1% at 3 months and 71.4% at 12 months. A significant improvement in visual acuity and reduction in central subfield thickness were observed at three and 12 months after focal laser photocoagulation (all p < 0.05). The characteristic hyperreflectivity within hyporeflective lesions on the IR image in conjunction with OCT helps identify the TelCap. Our results suggest that IR imaging and OCT-guided focal laser photocoagulation of TelCaps can improve functional and anatomical outcomes in persistent DME.


Assuntos
Retinopatia Diabética/complicações , Fotocoagulação a Laser/métodos , Edema Macular/diagnóstico por imagem , Telangiectasia/diagnóstico por imagem , Idoso , Feminino , Humanos , Edema Macular/etiologia , Edema Macular/cirurgia , Masculino , Estudos Retrospectivos , Cirurgia Assistida por Computador , Telangiectasia/etiologia , Telangiectasia/cirurgia , Tomografia de Coerência Óptica
16.
Sci Rep ; 11(1): 21663, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737335

RESUMO

This study aimed to validate and evaluate deep learning (DL) models for screening of high myopia using spectral-domain optical coherence tomography (OCT). This retrospective cross-sectional study included 690 eyes in 492 patients with OCT images and axial length measurement. Eyes were divided into three groups based on axial length: a "normal group," a "high myopia group," and an "other retinal disease" group. The researchers trained and validated three DL models to classify the three groups based on horizontal and vertical OCT images of the 600 eyes. For evaluation, OCT images of 90 eyes were used. Diagnostic agreements of human doctors and DL models were analyzed. The area under the receiver operating characteristic curve of the three DL models was evaluated. Absolute agreement of retina specialists was 99.11% (range: 97.78-100%). Absolute agreement of the DL models with multiple-column model was 100.0% (ResNet 50), 90.0% (Inception V3), and 72.22% (VGG 16). Areas under the receiver operating characteristic curves of the DL models with multiple-column model were 0.99 (ResNet 50), 0.97 (Inception V3), and 0.86 (VGG 16). The DL model based on ResNet 50 showed comparable diagnostic performance with retinal specialists. The DL model using OCT images demonstrated reliable diagnostic performance to identify high myopia.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Miopia/diagnóstico , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Estudos Transversais , Aprendizado Profundo , Olho/patologia , Feminino , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Fibras Nervosas , Curva ROC , República da Coreia , Retina , Doenças Retinianas , Células Ganglionares da Retina , Estudos Retrospectivos , Campos Visuais
17.
Nanoscale ; 11(29): 13878-13884, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31304500

RESUMO

Stimulation of dendritic cells (DCs) by antigens (Ags) promotes an Ag-specific immune response that kills Ag-expressing pathogens. These biologically inspired nanocarriers have received much attention as tools to deliver cancer Ags to DCs. A polymer-templated protein nanoball having hemagglutinin (H1-NB) that mimics the influenza virus can be used as a cancer Ag delivery vehicle, as DCs show effective phagocytic activities against H1-NB without any adjuvant. In the present study, H1-NB containing ovalbumin (OVA), a model Ag (H1-OVA-NB), was prepared as an anti-cancer agent and evaluated for its effect on anticancer immunity. H1-OVA-NB treatments in C57BL/6 mice enhanced OVA-specific immune activation and efficiently inhibited B16-OVA tumor growth compared to control groups. Our results indicate that H1-NB is an effective carrier for Ag delivery to DCs and promotes immunotherapy to fight cancer.


Assuntos
Antígenos/imunologia , Células Dendríticas/imunologia , Hemaglutininas/química , Imunoterapia , Nanopartículas/química , Polímeros/química , Animais , Antígenos/química , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Portadores de Fármacos/química , Hemaglutininas/genética , Hemaglutininas/metabolismo , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Orthomyxoviridae/metabolismo , Ovalbumina/genética , Ovalbumina/imunologia , Ovalbumina/metabolismo
18.
Biomaterials ; 183: 234-242, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30176403

RESUMO

The generation of virus-mimetic nanoparticles has received much attention in developing a new vaccine for overcoming the limitations of current vaccines. Thus, a method, encompassing most viral features for their size, hydrophobic domain and antigen display, would represent a meaningful direction for the vaccine development. In the present study, a polymer-templated protein nanoball with direction oriented hemagglutinin1 on its surface (H1-NB) was prepared as a new influenza vaccine, exhibiting most of the viral features. Moreover, the concentrations of antigen on the particle surface were controlled, and its effect on immunogenicity was estimated by in vivo studies. Finally, H1-NB efficiently promoted H1-specific immune activation and cross-protective activities, which consequently prevented H1N1 infections in mice.


Assuntos
Hemaglutininas Virais/metabolismo , Hemaglutininas/química , Vacinas contra Influenza/química , Nanopartículas/química , Polímeros/química , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Células Dendríticas/fisiologia , Hemaglutininas/metabolismo , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nanopartículas/metabolismo , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Tamanho da Partícula , Baço/citologia
19.
Polymers (Basel) ; 9(4)2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30970824

RESUMO

This study demonstrates the synthesis of an amphiphilic block copolymer, Ni2+-nitrilotiracetic acid-end-functionalized-poly(poly(ethylene glycol)methyl ether methacrylate)-block-polystyrene (NTA-p(PEGMA-b-St)), morphology control via their self-assembly behavior and reversible bioconjugation of hexahistidine-tagged green fluorescent protein (His6-GFP) onto the surfaces of polymeric vesicles through nitrilotriacetic acid (NTA)-Ni2+-His interaction. First, the t-boc-protected-NTA-p(PEGMA-b-St) was synthesized by atom transfer radical polymerization. After the removal of the t-boc protecting group, the NTA group of the polymer was complexed with Ni2+. To induce self-assembly, water was added as a selective solvent to the solution of the copolymer in tetrahydrofuran (THF). Varying the water content of the solution resulted in various morphologies including spheres, lamellas and vesicles. Finally, polymeric vesicles decorated with green fluorescent protein (GFP) on their surfaces were prepared by the addition of His6-GFP into the vesicles solution. Reversibility of the binding between vesicles and His6-GFP was confirmed with a fluorescent microscope.

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