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1.
Biochem Biophys Res Commun ; 709: 149823, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38569245

RESUMO

Avian pathogenic Escherichia coli (APEC) causes enormous economic losses and is a primary contributor to the emergence of multidrug resistance (MDR)-related problems in the poultry industry. Bacteriophage (phage) therapy has been successful in controlling MDR, but phage-resistant variants have rapidly emerged through the horizontal transmission of diverse phage defense systems carried on mobile genetic elements. Consequently, while multiple phage cocktails are recommended for phage therapy, there is a growing need to explore simpler and more cost-effective phage treatment alternatives. In this study, we characterized two novel O78-specific APEC phages, φWAO78-1 and φHAO78-1, in terms of their morphology, genome, physicochemical stability and growth kinetics. Additionally, we assessed the susceptibility of thirty-two O78 APEC strains to these phages. We analyzed the roles of highly susceptible cells in intestinal settlement and fecal shedding (susceptible cell-assisted intestinal settlement and shedding, SAIS) of phages in chickens via coinoculation with phages. Furthermore, we evaluated a new strategy, susceptible cell-assisted resistant cell killing (SARK), by comparing phage susceptibility between resistant cells alone and a mixture of resistant and highly susceptible cells in vitro. As expected, high proportions of O78 APEC strains had already acquired multiple phage defense systems, exhibiting considerable resistance to φWAO78-1 and φHAO78-1. Coinoculation of highly susceptible cells with phages prolonged phage shedding in feces, and the coexistence of susceptible cells markedly increased the phage susceptibility of resistant cells. Therefore, the SAIS and SARK strategies were demonstrated to be promising both in vivo and in vitro.


Assuntos
Bacteriófagos , Infecções por Escherichia coli , Doenças das Aves Domésticas , Animais , Bacteriófagos/genética , Galinhas , Escherichia coli/genética , Colífagos , Morte Celular , Doenças das Aves Domésticas/terapia
2.
NPJ Vaccines ; 9(1): 34, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360752

RESUMO

The implications of administration of mRNA vaccines to individuals with chronic inflammatory diseases, including myocarditis, rheumatoid arthritis (RA), and inflammatory bowel disease (IBD), are unclear. We investigated mRNA vaccine effects in a chronic inflammation mouse model implanted with an LPS pump, focusing on toxicity and immunogenicity. Under chronic inflammation, mRNA vaccines exacerbated cardiac damage and myocarditis, inducing mild heart inflammation with heightened pro-inflammatory cytokine production and inflammatory cell infiltration in the heart. Concurrently, significant muscle damage occurred, with disturbances in mitochondrial fusion and fission factors signaling impaired muscle repair. However, chronic inflammation did not adversely affect muscles at the vaccination site or humoral immune responses; nevertheless, it partially reduced the cell-mediated immune response, particularly T-cell activation. These findings underscore the importance of addressing mRNA vaccine toxicity and immunogenicity in the context of chronic inflammation, ensuring their safe and effective utilization, particularly among vulnerable populations with immune-mediated inflammatory diseases.

3.
Viruses ; 15(5)2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37243157

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is major economic problem given its effects on swine health and productivity. Therefore, we evaluated the genetic stability of a codon pair de-optimized (CPD) PRRSV, E38-ORF7 CPD, as well as the master seed passage threshold that elicited an effective immune response in pigs against heterologous virus challenge. The genetic stability and immune response of every 10th passage (out of 40) of E38-ORF7 CPD was analyzed through whole genome sequencing and inoculation in 3-week-old pigs. E38-ORF7 CPD passages were limited to 20 based on the full-length mutation analysis and animal test results. After 20 passages, the virus could not induce antibodies to provide effective immunity and mutations accumulated in the gene, which differed from the CPD gene, presenting a reason for low infectivity. Conclusively, the optimal passage number of E38-ORF7 CPD is 20. As a vaccine, this may help overcome the highly diverse PRRSV infection with substantially enhanced genetic stability.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Vacinas Virais , Suínos , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Síndrome Respiratória e Reprodutiva Suína/genética , Mutação , Códon , Vacinas Virais/genética , Anticorpos Antivirais
4.
Virology ; 579: 119-127, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36669328

RESUMO

Codon pair deoptimization (CPD) attenuated type I porcine reproductive and respiratory syndrome virus (PRRSV). Infectious clones covering the full genome of a Korean type I PRRSV (E38) were synthesized, and CPD induced nine synonymous mutants of NSP1 (n = 1) and ORF7 (n = 8). In a trial to rescue live viruses from infectious clones, only four clones with mutations at nt 177 downstream of ORF7 were rescued, which showed a substantial decrease in cellular replication ability. The rescue-failed clones had two common mutation sites with a high minimum free energy and significantly modified RNA secondary structure relative to the original virus. In infected pigs, CPD viruses demonstrated significantly lower replication ability and pathogenicity than the original virus. However, immune response level induced by the attenuated viruses and the original virus was similar. This is the first study to demonstrate that type I PRRSV virulence can be attenuated through CPD application to ORF7.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Vacinas Virais , Vírus , Animais , Suínos , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Replicação Viral/genética , Códon , Mutação , Vírus/genética , Imunidade , Síndrome Respiratória e Reprodutiva Suína/genética , Vacinas Virais/genética
5.
Collegian ; 30(2): 264-269, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36128018

RESUMO

Background: Although rural nurses' roles are indispensable in coronavirus disease 2019 (COVID-19) management, increased roles, workload, burnout, and reduced job satisfaction can hinder their work, potentially affecting nurses' disaster nursing competencies. Aim: The aim of the study was to identify the predictors of rural nurses' disaster nursing competencies during the COVID-19 pandemic. Methods: Nurses from rural community hospitals in South Korea (N=204) were surveyed during June-July 2021. We used the Professional Quality of Life and Disaster Nursing Preparedness-Response Competencies questionnaires. Multiple regression analysis was performed to identify the predictors of disaster nursing competencies. Findings: The mean score for disaster nursing competency of the 204 participants was 110.80 (standard deviation=19.14). Disaster nursing competencies correlated with age, nursing career, compassion satisfaction, and secondary traumatic stress. Compassion satisfaction (ß=.27, P=.004), prior disaster nursing education (ß=.19, P=.005), and prior participation in disaster nursing care (ß=.16, P=.022) predicted disaster nursing competencies, together accounting for 24.2% of the variance. Discussion: Our findings imply that increasing opportunities for continuing education regarding disaster nursing is crucial to enhance the related competencies in rural nurses. This study also highlights the necessity for stakeholders to develop programs aimed at increasing rural nurses' compassion satisfaction. Conclusion: Prior disaster nursing education, prior participation in disaster nursing care, and compassion satisfaction predicted disaster nursing competencies among rural nurses, with compassion satisfaction being the strongest predictor.

6.
Nurs Health Sci ; 24(3): 699-707, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35717611

RESUMO

On-site clinical training, which has been greatly hindered during the COVID-19 pandemic, is essential in nursing practicum. This study aimed to identify the predictors of nursing students' motivational and self-regulated learning in clinical nursing practicum during the pandemic. This cross-sectional study aimed to identify the predictors of motivational and self-regulated learning among nursing students in clinical nursing practicum during the COVID-19 pandemic. An online survey was completed by 195 nursing students in Korea in 2021. Students' moral sensitivity and motivational and self-regulated learning were assessed using the Moral Sensitivity Questionnaire and the Motivated Strategies for Learning Questionnaire. Multiple regression analysis revealed that moral sensitivity was the most potent predictor of motivational and self-regulated learning, followed by online clinical practicum experience, determination to become a nurse, and online practicum type; these factors explained 21.0% of the variance. Practicum courses using a tailored hybrid model, combining online and in-person approaches for imparting nursing practices and inspiring moral sensitivity, can enhance nursing students' motivational and self-regulated learning. Modules to enhance nursing students' moral sensitivity should be included in online practicum curricula.


Assuntos
COVID-19 , Bacharelado em Enfermagem , Estudantes de Enfermagem , Estudos Transversais , Humanos , Pandemias
7.
J Nanobiotechnology ; 20(1): 227, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35551612

RESUMO

BACKGROUND: There has been growing concern regarding the impact of air pollution, especially fine dust, on human health. However, it is difficult to estimate the toxicity of fine dust on the human body because of its diverse effects depending on the composition and environmental factors. RESULTS: In this study, we focused on the difference in the biodistribution of fine dust according to the size distribution of particulate matter after inhalation into the body to predict its impact on human health. We synthesized Cy7-doped silica particulate matters (CSPMs) having different particle sizes and employed them as model fine dust, and studied their whole-body in vivo biodistribution in BALB/c nude mice. Image-tracking and quantitative and qualitative analyses were performed on the ex vivo organs and tissues. Additionally, flow cytometric analysis of single cells isolated from the lungs was performed. Smaller particles with a diameter of less than 100 nm (CSPM0.1) were observed to be removed relatively rapidly from the lungs upon initial inhalation. However, they were confirmed to accumulate continuously over 4 weeks of observation. In particular, smaller particles were found to spread rapidly to other organs during the early stages of inhalation. CONCLUSIONS: The results show in vivo behavioral differences that arisen from particle size through mouse experimental model. Although these are far from the human inhalation studies, it provides information that can help predict the effect of fine dust on human health. This study might provide with insights on association between CSPM0.1 accumulation in several organs including the lungs and adverse effect to underlying diseases in the organs.


Assuntos
Poluentes Atmosféricos , Poeira , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Animais , Poeira/análise , Camundongos , Camundongos Nus , Tamanho da Partícula , Material Particulado/toxicidade , Distribuição Tecidual
8.
Tissue Eng Regen Med ; 19(5): 1099-1111, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35460494

RESUMO

BACKGROUND: Bone marrow-derived mesenchymal stem cells (BMSCs) and bone morphogenetic protein-2 (BMP-2) have been studied for bone repair because they have regenerative potential to differentiate into osteoblasts. The development of injectable and in situ three-dimensional (3D) scaffolds to proliferate and differentiate BMSCs and deliver BMP-2 is a crucial technology in BMSC-based tissue engineering. METHODS: The proliferation of mouse BMSCs (mBMSCs) in collagen/poly-γ-glutamic acid (Col/γ-PGA) hydrogel was evaluated using LIVE/DEAD and acridine orange and propidium iodide assays. In vitro osteogenic differentiation and the gene expression level of Col/γ-PGA(mBMSC/BMP-2) were assessed by alizarin red S staining and quantitative reverse-transcription polymerase chain reaction. The bone regeneration effect of Col/γ-PGA(mBMSC/BMP-2) was evaluated in a mouse calvarial bone defect model. The cranial bones of the mice were monitored by micro-computed tomography and histological analysis. RESULTS: The developed Col/γ-PGA hydrogel showed low viscosity below ambient temperature, while it provided a high elastic modulus and viscous modulus at body temperature. After gelation, the Col/γ-PGA hydrogel showed a 3D and interconnected porous structure, which helped the effective proliferation of BMSCs with BMP-2. The Col/γ-PGA (mBMSC/BMP-2) expressed more osteogenic genes and showed effective orthotopic bone formation in a mouse model with a critical-sized bone defect in only 3-4 weeks. CONCLUSION: The Col/γ-PGA(mBMSC/BMP-2) hydrogel was suggested to be a promising platform by combining collagen as a major component of the extracellular matrix and γ-PGA as a viscosity reducer for easy handling at room temperature in BMSC-based bone tissue engineering scaffolds.


Assuntos
Hidrogéis , Células-Tronco Mesenquimais , Laranja de Acridina/metabolismo , Laranja de Acridina/farmacologia , Animais , Regeneração Óssea , Colágeno/metabolismo , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteogênese , Ácido Poliglutâmico/análogos & derivados , Propídio/metabolismo , Propídio/farmacologia , Microtomografia por Raio-X
9.
Nurs Health Sci ; 24(2): 447-457, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35352456

RESUMO

Equity is an emerging issue across all sectors of society, and one of the frequently raised concerns in nursing education is gender inequity. An accurate assessment appears to be a key component in creating an environment of gender equity in nursing education. This study aimed to develop a scale of gender equity in nursing education and establish its validity and reliability. In total, 341 senior nursing students participated in the psychometric evaluation of the Gender Equity Scale in Nursing Education. This psychometric evaluation revealed that the 4-subdomain (personal experience of gender inequity, perceptions of gender roles, gender discrimination, and gender biases in class), 23-item measure possesses both good reliability and validity, as well as a good level of internal consistency. The Gender Equity Scale in Nursing Education was developed as a self-report questionnaire for both female and male students and considers gender role stereotypes, gender-biased educational climates, gender discrimination, and gender inequity in nursing education.


Assuntos
Educação em Enfermagem , Estudantes de Enfermagem , Feminino , Equidade de Gênero , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
10.
Pathogens ; 10(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34959599

RESUMO

In recent years, porcine circovirus type 2d (PCV2d) has achieved a dominant position worldwide. Various PCV2d capsid-based vaccines have been used to alleviate concerns regarding the emergence of the variant. This study aimed to determine the dosage of recombinant PCV2d capsid protein to induce protective efficacy against experimental challenge with a virulent PCV2d strain. Conventional 3-week-old pigs were intramuscularly inoculated with different doses of the protein (60, 20, 10 and 2 µg). Four weeks after vaccination, all pigs were challenged with pathogenic PCV2d (SNU140003), which was isolated from a farm severely experiencing PCV2-associated disease in Korea. Vaccination with greater than 10 µg of the capsid protein caused a significant (p < 0.05) reduction in PCV2d viremia, lymphoid lesions and lymphoid PCV2 antigen levels in vaccinated challenged pigs compared to unvaccinated challenged pigs. The vaccination also resulted in significantly higher (p < 0.05) titers of neutralizing antibodies against PCV2d. However, the pigs vaccinated with 2 µg had significantly lower neutralizing antibody titers than the other vaccinated groups. They showed a similar level of challenged PCV2d in serum and lymphoid lesion score compared to unvaccinated challenged pigs. The difference in efficacy among the vaccinated groups indicates that there may be a baseline dosage to induce sufficient neutralizing antibodies to prevent viral replication in pigs. In conclusion, at least 10 µg dosage of capsid protein is essential for stable protective efficacy against PCV2d in a pig model.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34063432

RESUMO

This study designed an intervention based on logo-autobiography to reduce Korean college students' stress and depression and help them find meaning in their lives amidst the COVID-19 pandemic. A quasi-experimental design was used to conduct group interventions among college students. A total of 22 and 26 participants were included in the experimental and control groups, respectively. The experimental group received six sessions of a logo-autobiography for college students (LAC). The effects of the LAC interventions were assessed at baseline, post-intervention, and four weeks after the program's end to determine their retention rate. The effects of group, time, and the group-by-time interaction were verified using generalized estimating equations with an autoregressive correlation structure. The experimental group exhibited significantly lower levels of stress and depression and higher levels concerning the meaning of life than the control group. However, only the effects on stress and the meaning of life continued four weeks after the intervention's end. Based on this study's results, LAC can be considered a useful method for reducing stress and depression in college students who have just started their adult life, as well as for aiding them in their pursuit for the meaning of life.


Assuntos
COVID-19 , Pandemias , Adulto , Humanos , SARS-CoV-2 , Estudantes
12.
Artigo em Inglês | MEDLINE | ID: mdl-33807772

RESUMO

This study aimed to identify the relationships between gender role stereotypes (GRS), patriarchal family environment, and major satisfaction (MS) and their associated factors in nursing students. A total of 195 nursing students (154 women, 41 men) were surveyed online in South Korea from May to June 2020. The Gender Role Stereotype Inventory was used to assess gender role stereotypes, while patriarchal family environment and MS were evaluated using a 11-item instrument for testing patriarchal family environment and the Major Satisfaction Inventory, respectively. Men demonstrated stronger gender role stereotypes and patriarchal family culture than women. Patriarchal family culture was significantly correlated with gender role stereotypes and MS. A multiple regression analysis was performed to identify the effects of age, academic performance, motive for MS, intellectual GRS, social GRS, and patriarchal family environment on MS. The explanatory power of this model was 12.2%. Younger age, higher grade point average, voluntary selection of major, lower intellectual gender stereotypes, and higher social gender stereotypes predicted higher MS. Further studies on cultures in Asia and the world are needed to understand the impact of the patriarchal family culture and gender role stereotypes of nursing students on school adaptation.


Assuntos
Estudantes de Enfermagem , Ásia , Feminino , Papel de Gênero , Humanos , Masculino , Satisfação Pessoal , República da Coreia , Estereotipagem
13.
BMC Vet Res ; 16(1): 452, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228643

RESUMO

BACKGROUND: Mycoplasma hyopneumoniae (M. hyopneumoniae), a representative pathogen causing swine enzootic pneumonia, generally infects piglets vertically. However, it is difficult to ascertain the M. hyopneumoniae infection state of sows due to limited detection methods. This report investigated sow herd stability by applying nested PCR to laryngeal swabs of suckling pigs, which is reportedly the most sensitive method. RESULTS: M. hyopneumoniae was detected in 14 farms (63.6%) and 127 piglets (6.5%). The prevalence of sows likely to transmit M. hyopneumoniae in herds (11.1%) was calculated. In addition, there was a significant difference in detection rates among farms depending on herd size, gilt replacement rate, acclimation method, and antibiotic usage, suggesting various parameters that influence sow stability. CONCLUSIONS: The results demonstrated that laryngeal swabs from suckling pigs have provided useful information regarding vertical transmission from sows in South Korean farm conditions. This result demonstrated that farms with larger herd sizes, higher gilt replacement rates, and a practice of naturally exposing gilts for acclimation had higher detection rates in weaning piglets, indicating an unstable sow infection state.


Assuntos
Mycoplasma hyopneumoniae/isolamento & purificação , Pneumonia Suína Micoplasmática/epidemiologia , Pneumonia Suína Micoplasmática/transmissão , Criação de Animais Domésticos/métodos , Animais , Feminino , Transmissão Vertical de Doenças Infecciosas , Pneumonia Suína Micoplasmática/microbiologia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , Prevalência , República da Coreia , Sus scrofa , Suínos
14.
Biochem Biophys Res Commun ; 496(3): 846-851, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29374509

RESUMO

Viral pathogens have evolved a wide range of tactics to evade host immune responses and thus propagate effectively. One efficient tactic is to divert host immune responses toward an immunodominant decoy epitope and to induce non-neutralizing antibodies toward this epitope. Therefore, it is expected that the amount of decoy epitope in a subunit vaccine can affect the level of neutralizing antibody in an immunized animal. In this study, we tested this hypothesis by generating an antibody specific to the decoy epitope on the capsid protein of porcine circovirus type 2 (PCV2). Using this antibody, we found that two commercial vaccines contained statistically different amounts of the decoy epitope. The vaccine with lower levels of decoy epitope induced a significantly higher level of neutralizing antibody after immunization. This antibody can be used as an analytical tool to monitor the quality of a vaccine from batch to batch.


Assuntos
Vacinas contra Adenovirus/administração & dosagem , Anticorpos Neutralizantes/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Circovirus/imunologia , Vacinas Virais/imunologia , Vacinas Virais/toxicidade , Animais , Anticorpos Neutralizantes/sangue , Circovirus/efeitos dos fármacos , Epitopos/imunologia , Cobaias , Resultado do Tratamento , Vacinação/métodos
15.
Int J Nanomedicine ; 12: 2607-2620, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28408827

RESUMO

Injectable and stimuli-responsive hydrogels have attracted attention in molecular imaging and drug delivery because encapsulated diagnostic or therapeutic components in the hydrogel can be used to image or change the microenvironment of the injection site by controlling various stimuli such as enzymes, temperature, pH, and photonic energy. In this study, we developed a novel injectable and photoresponsive composite hydrogel composed of anticancer drugs, imaging contrast agents, bio-derived collagen, and multifaceted anionic polypeptide, poly (γ-glutamic acid) (γ-PGA). By the introduction of γ-PGA, the intrinsic temperature-dependent phase transition behavior of collagen was modified to a low viscous sol state at room temperature and nonflowing gel state around body temperature. The modified temperature-dependent phase transition behavior of collagen/γ-PGA hydrogels was also evaluated after loading of near-infrared (NIR) fluorophore, indocyanine green (ICG), which could transform absorbed NIR photonic energy into thermal energy. By taking advantage of the abundant carboxylate groups in γ-PGA, cationic-charged doxorubicin (Dox) and hydrophobic MnFe2O4 magnetic nanoparticles were also incorporated successfully into the collagen/γ-PGA hydrogels. By illumination of NIR light on the collagen/γ-PGA/Dox/ICG/MnFe2O4 hydrogels, the release kinetics of Dox and magnetic relaxation of MnFe2O4 nanoparticles could be modulated. The experimental results suggest that the novel injectable and NIR-responsive collagen/γ-PGA hydrogels developed in this study can be used as a theranostic platform after loading of various molecular imaging probes and therapeutic components.


Assuntos
Colágeno/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Poliglutâmico/análogos & derivados , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Liberação Controlada de Fármacos , Feminino , Hidrogéis/química , Concentração de Íons de Hidrogênio , Verde de Indocianina/administração & dosagem , Magnetismo , Camundongos Endogâmicos BALB C , Nanopartículas/química , Transição de Fase , Ácido Poliglutâmico/química , Temperatura
16.
Biomater Sci ; 5(2): 285-294, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-27975097

RESUMO

Mesenchymal stem cells (MSCs) can ameliorate renal injury and accelerate repair of acute kidney injury. Herein, we developed a collagen/poly(γ-glutamic acid) (γ-PGA) hydrogel as an injectable scaffold for the delivery of mouse MSCs (mMSCs) and anti-oxidant drugs into injured sites. By the introduction of γ-PGA into conventional collagen, the viscosity of collagen was reduced at ambient temperature for easy handling, while the elastic and viscous moduli of collagen were increased and a new porous structure was generated near body temperature. When in situ gel-forming collagen/γ-PGA hydrogels loaded with mMSCs and α-lipoic acid (LA) were administered to a mouse model of renal dysfunction, they significantly attenuated the level of blood urea nitrogen and creatinine, which resulted from the increased retention of therapeutic mMSCs and the controlled release of anti-oxidant drugs at the injured site. These findings suggested that this novel type of hydrogel could be applied as an injectable scaffold for use in regenerative medicine.


Assuntos
Colágeno/química , Hidrogéis/química , Nefropatias/terapia , Células-Tronco Mesenquimais , Ácido Poliglutâmico/análogos & derivados , Ácido Tióctico/farmacologia , Alicerces Teciduais/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Cisplatino , Colágeno/administração & dosagem , Modelos Animais de Doenças , Hidrogéis/administração & dosagem , Nefropatias/tratamento farmacológico , Nefropatias/patologia , Nefropatias/prevenção & controle , Transplante de Células-Tronco Mesenquimais , Camundongos , Ácido Poliglutâmico/administração & dosagem , Ácido Poliglutâmico/química , Ácido Tióctico/uso terapêutico
17.
Int J Nanomedicine ; 11: 5621-5632, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27822040

RESUMO

In this research, we synthesized bioderived poly(amino acid) hydrogel particles that showed pH-dependent membrane-disrupting properties and controlled cytosolic delivery of antitumor drugs. Poly(γ-glutamic acid) (γ-PGA) that has been produced extensively using bacteria, especially those of Bacillus subtilis species, was modified with cholesterol (γ-PGA/Chol), and the γ-PGA/Chol conjugates were used to form polymeric nanoparticles the size of 21.0±1.1 nm in aqueous solution. When the polymeric nanoparticles were mixed with doxorubicin (Dox), raspberry-like hydrogel particles (RBHPs) were formed by the electrostatic interaction between the cationically charged Dox and the anionically charged nanoparticles. The average size and surface charge of the RBHPs in aqueous solution were 444.9±122.5 nm and -56.44 mV, respectively. The loaded amount of Dox was approximately 63.9 µg/mg of RBHPs. The RBHPs showed controlled drug release behavior in both in vitro and ex vivo cell-based experiments. Through fluorescence microscopy and fluorescence-activated cell sorting, the cellular uptake of RBHPs into human cervical cancer cells (HeLa) was analyzed. The cytotoxic effect, evaluated by the methyl tetrazolium salt assay, was dependent on both the concentration of RBHPs and the treatment time. The pH-dependent membrane-disrupting properties of the RBHPs and the subsequent cytosolic delivery of Dox were evaluated using a standard hemolysis assay. Upon an increase in hydrophobicity at the lysosomal acidic pH, RBHPs could easily interact, penetrate cell membranes, and destabilize them. Taken together, the data suggested that RBHPs could be used as drug delivery carriers after loading with other therapeutic drugs, such as proteins or small interfering RNA for cancer therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Membrana Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas/administração & dosagem , Ácido Poliglutâmico/análogos & derivados , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/química , Citosol/metabolismo , Doxorrubicina/química , Portadores de Fármacos/química , Eritrócitos/efeitos dos fármacos , Feminino , Citometria de Fluxo , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas/química , Ácido Poliglutâmico/química , Rubus , Ovinos , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
18.
Angew Chem Int Ed Engl ; 55(36): 10612-5, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27467415

RESUMO

The design of inhibitors of intracellular protein-protein interactions (PPIs) remains a challenge in chemical biology and drug discovery. We propose a cyclized helix-loop-helix (cHLH) peptide as a scaffold for generating cell-permeable PPI inhibitors through bifunctional grafting: epitope grafting to provide binding activity, and arginine grafting to endow cell-permeability. To inhibit p53-HDM2 interactions, the p53 epitope was grafted onto the C-terminal helix and six Arg residues were grafted onto another helix. The designed peptide cHLHp53-R showed high inhibitory activity for this interaction, and computational analysis suggested a binding mode for HDM2. Confocal microscopy of cells treated with fluorescently labeled cHLHp53-R revealed cell membrane penetration and cytosolic localization. The peptide inhibited the growth of HCT116 and LnCap cancer cells. This strategy of bifunctional grafting onto a well-structured peptide scaffold could facilitate the generation of inhibitors for intracellular PPIs.


Assuntos
Arginina/análogos & derivados , Arginina/farmacologia , Desenho de Fármacos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Mapas de Interação de Proteínas/efeitos dos fármacos , Sequência de Aminoácidos , Linhagem Celular Tumoral , Humanos , Simulação de Acoplamento Molecular , Conformação Proteica em alfa-Hélice , Mapeamento de Interação de Proteínas , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/metabolismo
19.
Molecules ; 21(5)2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27136523

RESUMO

In this study, we developed electrostatically self-assembled ternary nanocomplexes as a safe and effective non-viral vector for the delivery of plasmid DNA (pDNA) into human adipose-derived stem cells (hASCs). Although polyethylenimine (PEI) polymers initially showed excellent performance as gene delivery carriers, their broad use has been limited by cytotoxicity resulting from their strong positive charge. To reduce the cytotoxicity, we utilized anionic hyaluronic acid (HA) as a corona layer material for pDNA/PEI binary nanocomplexes. HA was also introduced to increase the targeting efficiency of pDNA/PEI nanocomplexes because HA has can bind CD44 that is highly expressed on the surface of hASCs. We confirmed that the addition of HA changed the surface charge of pDNA/PEI nanocomplexes from positive to negative. The pDNA/PEI/HA ternary nanocomplexes showed high transfection efficiency and low cytotoxicity compared with commercially available products. When hASCs were pretreated with HA to passivate CD44, the transfection efficiency of pDNA/PEI/HA nanocomplexes was significantly reduced. These results suggest that HA that can act as a targeting ligand to CD44 contributed to the improved transfection of pDNA into hASCs. Our novel pDNA/PEI/HA nanocomplexes may be used as an effective non-viral pDNA delivery system for hASCs.


Assuntos
DNA/metabolismo , Vetores Genéticos , Células-Tronco Mesenquimais , Nanopartículas , Plasmídeos/genética , Transfecção , Tecido Adiposo/citologia , Células Cultivadas , Humanos , Receptores de Hialuronatos/metabolismo , Polietilenoimina , Eletricidade Estática
20.
Cancer Sci ; 107(3): 267-73, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26748910

RESUMO

Epithelial-mesenchymal transition (EMT) has been closely related with invasive and metastatic properties of cancer. Recently, the convergence of DNA damage response and EMT in cancer development has received a great amount of scientific attention. Here, we showed that EMT is induced by the downregulation of RAP80, a well-known regulator for DNA damage response. The knockdown of RAP80 leads to EMT-like morphological changes and the increase of tumor sphere formation in non-adhesive culture. Mechanistically, RAP80 controls a reciprocal regulatory axis of ZEB1 (for EMT activation) and miR200c (for EMT inhibition). The downregulation of RAP80 increases ZEB1 protein and decreases miR200c expression to activate EMT signaling in the form of drastic inhibitions of E-cadherin, p16 and p21 expression. Using in vivo metastasis analysis, RAP80 knockdown cells are shown to dramatically metastasize into the lung and generate more malignant phenotype compared to controls. Interestingly, the expression level of RAP80 was positively correlated with the survival rate in lung adenocarcinoma and breast cancer patients. These findings indicate that RAP80 is a critical gatekeeper in impeding EMT-induced metastasis and malignant phenotypes of cancer as well as preserving DNA integrity.


Assuntos
Proteínas de Transporte/fisiologia , Transição Epitelial-Mesenquimal , Proteínas de Homeodomínio/metabolismo , Neoplasias Pulmonares/secundário , Proteínas Nucleares/fisiologia , Fatores de Transcrição/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Proteínas de Ligação a DNA , Feminino , Técnicas de Silenciamento de Genes , Células HeLa , Chaperonas de Histonas , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Homeobox 1 de Ligação a E-box em Dedo de Zinco
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