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This study identifies the stigma experienced by 12 bereaved parents 2 and 5 years after losing a child in the Sewol ferry disaster in South Korea. Using thematic analysis, we categorized the experience of stigma into two components based on Corrigan and Kosyluk's social cognitive model of stigma: public stigma and self-stigma, and each was analyzed into three types of stigma: stereotype, prejudice, and discrimination. We identified four additional factors related to stigma mitigation. The potential implications for characterizing the experiences of bereaved parents, particularly those facing stigma, are discussed in light of these findings in the longitudinal perspective.
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As a promising next-generation solar cell, the power conversion efficiency of a silicon quantum dot (Si-QD) solar cell is still low. In this work, the band-gap structure of a Si-QD layer was modified to improve the power conversion efficiency of a Si-QD solar cell. A stepwise band-gap Si-QD (SB Si-QD) layer with a high bandgap top layer (about 2.22 eV) and a low band-gap bottom layer (about 1.98 eV) was grown on a Si (100) substrate. The open circuit voltage and short circuit current were improved by band-gap engineering of the Si-QD absorption layer. As a result, the power conversion efficiency of the SB Si-QD solar cell increased from 16.50% to 17.50%, compared to that of a Si-QD solar cell with a uniform band gap. This results will provide a guide to design advanced Si-QD solar cells by considering the band-gap structure in the Si-QD absorption layer.
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Lithium-collaborating organic batteries (Li-[28]hexs) were investigated with [28]hexaphyrin(1.1.1.1.1.1) as an active electrode material. Each hexaphyrin of [28]Hex cathode ideally involved four electrons per unit cycle and performed a typical charge/discharge processes of Li-organic battery. Li-[28]Hex batteries set with fast charging rates showed reasonably stable charge and discharge performances over 200 cycles even though it caused incomplete (2~3 electrons) charge/discharge cycles due to failing the complete charging process. UV absorption changes of [28]hexaphyrin in CH2Cl2 were supplementary for the electrochemical oxidation, which performed a conversion from [28]hexaphyrin to [26]hexaphyrin.
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Fontes de Energia Elétrica , Lítio/química , Porfirinas/química , Cor , Eletroquímica , Eletrodos , Conformação Molecular , OxirreduçãoRESUMO
Peroxiredoxins (Prxs) play dual roles as both thiol-peroxidases and molecular chaperones. Peroxidase activity enables various intracellular functions, however, the physiological roles of Prxs as chaperones are not well established. To study the chaperoning function of Prx, we previously sought to identify heat-induced Prx-binding proteins as the clients of a Prx chaperone. By using His-tagged Prx I as a bait, we separated ubiquitin C-terminal hydrolase-L1 (UCH-L1) as a heat-induced Prx I binding protein from rat brain crude extracts. Protein complex immunoprecipitation with HeLa cell lysates revealed that both Prx I and Prx II interact with UCH-L1. However, Prx II interacted considerably more favorably with UCH-L1 than Prx I. Prx II exhibited more effective molecular chaperone activity than Prx I when UCH-L1 was the client. Prx II interacted with UCH-L1 through its C-terminal region to protect UCH-L1 from thermal or oxidative inactivation. We found that chaperoning via interaction through C-terminal region (specific-client chaperoning) is more efficient than that involving oligomeric structural change (general-client chaperoning). Prx II binds either thermally or oxidatively unfolding early intermediates of specific clients and thereby shifted the equilibrium towards their native state. We conclude that this chaperoning mechanism provides a very effective and selective chaperoning activity.
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Chaperonas Moleculares/metabolismo , Peroxirredoxinas/metabolismo , Ubiquitina Tiolesterase/metabolismo , Sequência de Aminoácidos , Animais , Domínio Catalítico , Linhagem Celular Tumoral , Células HeLa , Temperatura Alta , Humanos , Oxirredução , Estresse Oxidativo , Ligação Proteica , Estrutura Quaternária de Proteína , Ratos , Ubiquitina Tiolesterase/antagonistas & inibidores , Ubiquitina Tiolesterase/químicaRESUMO
Fusarium graminearum is a prominent plant pathogenic fungus causing Fusarium head blight in major cereal crops worldwide. To understand the molecular mechanisms underlying fungal development and virulence, large collections of F. graminearum mutants have been constructed. Cytochrome P450 monooxygenases (P450s) are widely distributed in organisms and are involved in a diverse array of molecular/metabolic processes; however, no systematic functional analysis of P450s has been attempted in filamentous fungi. In this study, we constructed a genome-wide deletion mutant set covering 102 P450s and analyzed these mutants for changes in 38 phenotypic categories, including fungal development, stress responses and responses to several xenobiotics, to build a comprehensive phenotypic dataset. Most P450 mutants showing defective phenotypes were impaired in a single phenotypic trait, demonstrating that our mutant library is a good genetic resource for further fungal genetic studies. In particular, we identified novel P450s specifically involved in virulence (5) and both asexual (1) and sexual development (2). Most P450s seem to play redundant roles in the degradation of xenobiotics in F. graminearum. This study is the first phenome-based functional analysis of P450s, and it provides a valuable genetic resource for further basic and applied biological research in filamentous fungi and other plant pathogens.
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Sistema Enzimático do Citocromo P-450/genética , Grão Comestível/microbiologia , Proteínas Fúngicas/genética , Fusarium/genética , Xenobióticos/metabolismo , Antifúngicos/metabolismo , Fusarium/patogenicidade , Técnicas de Inativação de Genes , Micélio/genética , Micélio/crescimento & desenvolvimento , Fenótipo , Doenças das Plantas/microbiologia , Deleção de Sequência , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Triticum/microbiologia , VirulênciaRESUMO
The importance of PPARγ (peroxisome proliferator-activated receptor γ) in gastric cancer (GC) is unclear. We investigated the role of PPARγ in GC cell lines and an animal model, and its prognostic significance of PPARγ in GC patients. We controlled PPARγ and galectin-9 expression by using siRNAs and lentiviral constructs. Interaction between PPARγ and galectin-9 was evaluated using luciferase and chromatin immunoprecipitation assays. PPARγ expression in GCs was determined by immunohistochemical staining of tissue microarrays and survival analysis was done. Overexpression of PPARγ was accompanied by increased galectin-9. Enhanced PPARγ or galectin-9 expression increased E-cadherin expression; decreased expression of N-cadherin, fibronectin, snail, twist and slug and reduced cell invasion and migration. PPARγ bound to the galectin-9 promoter region. Galectin-9 activity increased in PPARγ-overexpressing cells but decreased in PPARγ siRNA-treated cells. In a zebrafish xenograft model, the number of migrated cancer cells and number of fish with AGS cells in the tail vein were reduced in PPARγ-overexpressing GC cells. PPARγ was expressed in 462 of the 688 patients (69.2%) with GC. In 306 patients with intestinal-type GC, those with PPARγ-positive tumors had lower overall and cancer-specific mortalities than those with PPARγ-negative tumors. PPARγ expression was an independent prognostic factor for overall and GC-specific mortality in patients with intestinal-type GC (adjusted hazard ratio, 0.42; 95% CI, 0.22-0.81). PPARγ inhibits cell invasion, migration and epithelial-mesenchymal transition through upregulation of galectin-9 in vitro and in vivo.
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Galectinas/genética , PPAR gama/fisiologia , Neoplasias Gástricas/metabolismo , Animais , Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal , Galectinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Invasividade Neoplásica , Transplante de Neoplasias , PPAR gama/agonistas , Prognóstico , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais , Ligação Proteica , Rosiglitazona , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Tiazolidinedionas/farmacologia , Regulação para Cima , Peixe-ZebraRESUMO
Treatment of antiaromatic nickel(II) norcorrole with potassium cyanide provided nickel(II) 3-cyanonorcorrole with perfect regioselectivity without the help of a catalyst. The reaction of the nickel(II) norcorrole with phenol or thiophenol in the presence of a base also yielded substitution products. The antiaromatic 16π conjugation system in the norcorrole core was preserved in the functionalized products. Introduction of phenylthio groups significantly decreased the HOMO-LUMO gap and enhanced the near IR absorption property.
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A set of hybrids having gradual variation in distances between hexaphyrin and bodipy moieties, given by uses of phenylene, biphenylene, and triphenyelene bridges was prepared. Efficient PET processes from bodipy (donor) to [26]- or [28]hexaphyrin (acceptor) were successfully observed, where the PET speed was controlled by intramolecular distances between the donor and the acceptor. UV irradiation at 515â nm raised a band corresponding to the bodipy absorption. As the time delayed, the bodipy bands decreased and new absorption bands at 615 and 580â nm corresponding to respective absorption bands of [28]- and [26]-hybrids gradually appeared. Whereas the femtosecond transient absorption spectra of [28]/[26]-hybrids having terphenylene bridges completely showed energy transfers from bodipy to hexaphyrin, irradiation of the hybrids using 615 and 580â nm pulses did not induce opposite ways of the PET process. On the basis of enlarged center-to-center-distances of [26]-hybrids than those of [28]-hybrids, the set of [26]-hybrids resulted in slow decay/rise processes. PET parameters obtained with the experiments were fairly consistent with the PET parameters calculated.
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Most cervical cancers are caused by 15 high-risk (HR) and three probable high-risk (pHR) oncogenic types of human papillomavirus (HPV). However, current commercial HR HPV screening test products do not include pHR HPV genotypes. Recently, PapilloScreen has been developed to detect the 15 HR and three pHR HPV types. In this study, we evaluated the concordance levels and clinical performance of Hybrid Capture 2 (HC2), PapilloScreen, and a PCR sequencing assay in detecting HR and pHR HPV. The PapilloScreen (96.8 %) and PCR sequencing assay (96.8 %) demonstrated higher sensitivity than HC2 (80.7 %) for detecting HR and pHR HPV. The three assays showed similar specificities and positive or negative predictive values. The concordance levels were 86.5 % (κ = 0.68) and 86.5 % (κ = 0.67) between HC2 and PapilloScreen and between HC2 and PCR sequencing, respectively. A near-perfect concordance was observed between PapilloScreen and PCR sequencing (97.8 %, κ = 0.95). Overall, the agreement between the three assays suggests that the results obtained by the HC2 assay are more often discordant (12.6 %) than the PCR-based tests. In conclusion, PapilloScreen is highly sensitive for detecting high-grade CIN or cervical cancer. The PapilloScreen assay should be considered an accurate and sensitive method for detecting HR and pHR HPV infections and an epidemiological tool for prevalence studies as well as early diagnosis and intervention in HR and pHR HPV infections.
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Alphapapillomavirus/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções por Papillomavirus/virologia , Análise de Sequência de DNA/métodos , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alphapapillomavirus/classificação , Alphapapillomavirus/genética , DNA Viral/genética , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase/métodos , República da Coreia , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/diagnóstico , Adulto JovemRESUMO
3-Pyridyl-5,15-diazaporphyrin nickel(II) serves as a bidentate metalloligand for platinum(II), ruthenium(II), and rhenium(I) metal centers. Single-crystal X-ray diffraction analysis of these metal complexes unambiguously reveals the presence of a dative bond between the outer metal center and the meso-nitrogen atom. The UV/Vis absorption spectra of the complexes show substantially red-shifted bands which are perturbed by outer-metal coordination. This is due to the contribution of metal-to-ligand charge transfer interactions.
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Although aromatic compounds occupy a central position in organic chemistry, antiaromatic compounds have demonstrated little practical utility. Herein we report the application of an antiaromatic compound as an electrode-active material in rechargeable batteries. The performance of dimesityl-substituted norcorrole nickel(II) complex (NiNC) as a cathode-active material was examined with a Li metal anode. A maximum discharge capacity of about 207â mAhg(-1) was maintained after 100 charge/discharge cycles. Moreover, the bipolar redox property of NiNC enables the construction of a Li metal free rechargeable battery. The high performance of NiNC batteries demonstrates a prospective feature of stable antiaromatic compounds as electrode-active materials.
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The treatment of an antiaromatic norcorrole Ni(II) complex with a kinetically stabilized silylene provided ring-expansion products in excellent yields through the highly regio- and stereoselective insertion into the ß-ß pyrrolic CC bonds. The resultant Ni(II) porphyrinoid monoinsertion product exhibited relatively strong near-IR absorption bands due to the small HOMO-LUMO gap in spite of the disrupted cyclic π-conjugation by the silicon atom.
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Sexual reproduction is crucial for increasing the genetic diversity of populations and providing overwintering structures, such as perithecia and associated tissue, in the destructive plant pathogenic fungus Fusarium graminearum. While mating-type genes serve as master regulators in fungal sexual reproduction, the molecular mechanisms underlying this process remain elusive. Winged-helix DNA-binding proteins are key regulators of embryogenesis and cell differentiation in higher eukaryotes. These proteins are implicated in the morphogenesis and development of several fungal species. However, their involvement in sexual reproduction remains largely unexplored in F. graminearum. Here, we investigated the function of winged-helix DNA-binding proteins in vegetative growth, conidiation, and sexual reproduction, with a specific focus on the FgWING27, which is highly conserved among Fusarium species. Deletion of FgWING27 resulted in an abnormal pattern characterized by a gradual increase in the expression of mating-type genes during sexual development, indicating its crucial role in the stage-specific genetic regulation of MAT genes in the late stages of sexual development. Furthermore, using chromatin immunoprecipitation followed by sequencing analysis, we identified Fg17056 as a downstream gene of Fgwing27, which is essential for sexual reproduction. These findings underscore the significance of winged-helix DNA-binding proteins in fungal development and reproduction in F. graminearum, and highlight the pivotal role of Fgwing27 as a core genetic factor in the intricate genetic regulatory network governing sexual reproduction.IMPORTANCEFusarium graminearum is a devastating plant pathogenic fungus causing significant economic losses due to reduced crop yields. In Fusarium Head Blight epidemics, spores produced through sexual and asexual reproduction serve as inoculum, making it essential to understand the fungal reproduction process. Here, we focus on winged-helix DNA-binding proteins, which have been reported to play crucial roles in cell cycle regulation and differentiation, and address their requirement in the sexual reproduction of F. graminearum. Furthermore, we identified a highly conserved protein in Fusarium as a key factor in self-fertility, along with the discovery of its direct downstream genes. This provides crucial information for constructing the complex genetic regulatory network of sexual reproduction and significantly contribute to further research on sexual reproduction in Fusarium species.
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Achievement of long-term survival of patients with lung cancer treated with conventional chemotherapy is still difficult for treatment of metastatic and advanced tumors. Despite recent progress in investigational therapies, survival rates are still disappointingly low and novel adjuvant and systemic therapies are urgently needed. A recently elucidated secretory pathway is attracting considerable interest as a promising anticancer target. The cis-Golgi matrix protein, GOLGA2/GM130, plays an important role in glycosylation and transport of protein in the secretory pathway. In this study, the effects of short hairpin RNA (shRNA) constructs targeting GOLGA2/GM130 (shGOLGA2) on autophagy and lung cancer growth were evaluated in vitro and in vivo. Downregulation of GOLGA2/GM130 led to induction of autophagy and inhibition of glycosylation in A549 cells and in the lungs of K-ras(LA1) mice. Furthermore, downregulation of GOLGA2/GM130 decreased angiogenesis and cancer cell invasion in vitro and suppressed tumorigenesis in lung cancer mice model. The tumor specificity of sequence targeting GOLGA2/GM130 was also demonstrated. Taken together, these results suggest that induction of autophagy by shGOLGA2 may induce cell death rather than cell survival. Therefore, downregulation of GOLGA2/GM130 may be a potential therapeutic option for lung cancer.
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Adenocarcinoma/terapia , Autoantígenos/genética , Terapia Genética , Neoplasias Pulmonares/terapia , Proteínas de Membrana/genética , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/patologia , Animais , Autoantígenos/metabolismo , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Técnicas de Silenciamento de Genes , Glicosilação , Humanos , Pulmão/patologia , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/patologia , Proteínas de Membrana/metabolismo , Camundongos , Invasividade Neoplásica , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Neovascularização Patológica/terapia , Proteínas Proto-Oncogênicas p21(ras)/genética , Interferência de RNA , RNA Interferente Pequeno/genéticaRESUMO
A shapely figure: A [32]octaphyrin(1.0.1.0.1.0.1.0) bis[palladium(II)] complex was selectively obtained through a metal-templated intermolecular homocoupling of a α,α'-dibromodipyrrin palladium(II) complex without formation the norcorrole. The weak antiaromatic character of the figure-eight [32]octaphyrin(1.0.1.0.1.0.1.0) system has been elucidated by spectroscopic measurements and DFT calculations.
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There have been no detailed investigations regarding solid-phase-extraction (SPE) optimization and screening for the degradation products of ethyl (1-(diethylamino)ethylidene)phosphoramidofluoridate (A234) in various environmental samples. Therefore, as a first step in the selective SPE of the degradation products of A234, we optimized the SPE adsorption and extraction parameters for the A234 degradation product ethylhydrogen (1-(diethylamino)ethylidene)phosphoramidate (cpd 1). Among various SPE cartridges, the Si cartridge (500 mg, 3 mL) selectively extracted cpd 1 using an elution volume of 4 mL of 25% H2O in acetonitrile, which eliminated most interference without cpd 1 loss during loading and washing. In addition, the sorbent capacity is also critical in the adsorption of cpd 1. The Si cartridge (500 mg, 3 mL) retained cpd 1 in the concentration range 1-10 µg/mL. The linearity of detector response of cpd 1 in deionized H2O was studied in the range of 1.0-100 ng/mL and showed good linearity with γ2 ranging from 0.9979 to 0.996. The limits of detection for cpd 1 are 10 ng/mL in the product-scan mode and 100 ng/mL in the full-scan mode. Also, after we optimized the SPE method, we validated the precision and accuracy of the Si-cartridge extraction method in real soil samples with diverse concentrations. The precision ranged from 2.5% to 5.3%. This newly developed SPE is applicable to the analysis of a degradation product of Novichok A234 in various environmental matrices, such as water, soil and sand, in the Organization for the Prohibition of Chemical Weapons (OPCW) proficiency test and unknown samples collected from suspected sites.
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Extração em Fase Sólida , Poluentes Químicos da Água , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análiseRESUMO
The skin sensitization potential of agrochemicals can be assessed using laboratory methods such as the keratinocyte activation assay so that their use in regulatory toxicology might replace experimental animal testing. Here, we evaluated the skin sensitization potential of 11 agrochemicals by using an antioxidant response element-nuclear factor erythroid 2 luciferase assay in KeratinoSens and LuSens cells and applying a skin sensitization adverse outcome pathway (AOP). The KeratinoSens and LuSens assays consistently evaluated the skin sensitization potential of 10/11 agrochemicals with reference to animal testing databases. Benomyl, pretilachlor, fluazinam, terbufos, butachlor, and carbosulfan were correctly detected as sensitizers, and glufosinate ammonium, oxiadiazon, tebuconazole, and etofenprox were correctly detected as non-sensitizers. For diazinon, the skin sensitizing potential was positive in the KeratinoSens assay but not in the LuSens assay. These results suggest that the evaluation of in vitro skin sensitization using the AOP mechanism can be applied to assess active agrochemicals.
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INTRODUCTION: C-C chemokine receptor type 7 (CCR7) plays an important role in chemotactic and metastatic responses in various cancers, including breast cancer. In the present study, the authors demonstrated that microRNA (miRNA) let-7a downregulates CCR7 expression and directly influences the migration and invasion of breast cancer cells. METHODS: The expression of CCR7, its ligand CCL21, and let-7a was detected in breast cancer cell lines and in breast cancer patient tissues. Synthetic let-7a and an inhibitor of let-7a were transfected into MDA-MB-231 and MCF-7 breast cancer cells, respectively, and cell proliferation, cell migration, and invasion assays were performed. To confirm the fact that 3'UTR of CCR7 is a direct target of let-7a, a luciferase assay for the reporter gene expressing the let-7a binding sites of CCR7 3'UTR was used. An in vivo invasion animal model system using transparent zebrafish embryos was also established to determine the let-7a effect on breast cancer cell invasion. RESULTS: First, a higher expression of both CCR7 and CCL21 in malignant tissues than in their normal counterparts from breast cancer patients was observed. In addition, a reverse correlation in the expression of CCR7 and let-7a in breast cancer cell lines and breast cancer patient tissues was detected. Synthetic let-7a decreased breast cancer cell proliferation, migration, and invasion, as well as CCR7 protein expression in MDA-MB-231 cells. The let-7a inhibitor reversed the let-7a effects on the MCF-7 cells. The 3'UTR of CCR7 was confirmed as a direct target of let-7a by using the luciferase assay for the reporter gene expressing let-7a CCR7 3'UTR binding sites. Notably, when analyzing in vivo invasion, MDA-MB 231 cells after synthetic let-7a transfection were unable to invade the vessels in zebrafish embryos. CONCLUSIONS: The results from the present study suggest that targeting of CCL21-CCR7 signaling is a valid approach for breast cancer therapy and that let-7a directly binds to the 3'UTR of CCR7 and blocks its protein expression, thereby suppressing migration and invasion of human breast cancer cells. Furthermore, the present study underscores the therapeutic potential of let-7a as an antitumor and antimetastatic manager in breast cancer patients.
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Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Movimento Celular , Regulação para Baixo , MicroRNAs/fisiologia , Receptores CCR7/genética , Regiões 3' não Traduzidas , Animais , Sequência de Bases , Sítios de Ligação , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Quimiocina CCL21/genética , Quimiocina CCL21/metabolismo , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Transplante de Neoplasias , Interferência de RNA , Receptores CCR7/metabolismo , Peixe-ZebraRESUMO
Cationic polymers have been the subject of intense research as nonviral gene delivery systems due to several advantages in comparison with viral vectors. However, the nonsimultaneous combination of high transfection efficiency and low cytotoxicity of nonviral vectors for gene delivery has long been an issue for scientists looking into ways to deliver genes into cells. Toward this goal, we designed, synthesized, and evaluated a safe and accelerated gene transfer system through polysorbitol-mediated transporter (PSMT) based on sorbitol diacrylate (SDA) and low molecular weight polyethylenimine (LMW PEI). The PSMT formed stable complexes with plasmid DNA in serum. The nano sizes and spherical shapes of PSMT/DNA complexes are not toxic, even at a high concentration of PSMT. The higher transfection efficiency of PSMT compared to PEI 25K was observed both in vitro, despite the existence of many hydroxyl groups, and in vivo. These improvements presumably stem from the osmotic property of polysorbitol and endosomal buffer capacity of PEI in PSMT. Most importantly, we confirmed that the selective cavaeolae endocytic pathway played a role in high transfection efficiency by osmotic PSMT-mediated gene delivery. We propose that PSMT is a promising nonviral carrier for the effective gene delivery to cancer cells via synergistic effects derived from rapid cellular uptake through the caveolae endocytic pathway and a high endosomal buffering capacity.
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Endocitose/fisiologia , Técnicas de Transferência de Genes , Poliésteres/química , Poliésteres/metabolismo , Polietilenoimina/análogos & derivados , Transfecção/métodos , Animais , Linhagem Celular Tumoral , Citometria de Fluxo , Células HeLa , Humanos , Masculino , Camundongos , Osmose , Polietilenoimina/química , Polietilenoimina/metabolismoRESUMO
Magnetic nanoparticles (MNPs) represent a subclass within the overall category of nanomaterials and are widely used in many applications, particularly in the biomedical sciences such as targeted delivery of drugs or genes, in magnetic resonance imaging, and in hyperthermia (treating tumors with heat). Although the potential benefits of MNPs are considerable, there is a distinct need to identify any potential toxicity associated with these MNPs. The potential of MNPs in drug delivery stems from the intrinsic properties of the magnetic core combined with their drug loading capability and the biomedical properties of MNPs generated by different surface coatings. These surface modifications alter the particokinetics and toxicity of MNPs by changing protein-MNP or cell-MNP interactions. This review contains current advances in MNPs for drug delivery and their possible organ toxicities associated with disturbance in body iron homeostasis. The importance of protein-MNP interactions and various safety considerations relating to MNP exposure are also addressed.