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1.
Sci Rep ; 14(1): 14079, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890341

RESUMO

While cryogenic electron microscopy (cryo-EM) is fruitfully used for harvesting high-resolution structures of sizable macromolecules, its application to small or flexible proteins composed of small domains like immunoglobulin (IgG) remain challenging. Here, we applied single particle cryo-EM to Rituximab, a therapeutic IgG mediating anti-tumor toxicity, to explore its solution conformations. We found Rituximab molecules exhibited aggregates in cryo-EM specimens contrary to its solution behavior, and utilized a non-ionic detergent to successfully disperse them as isolated particles amenable to single particle analysis. As the detergent adversely reduced the protein-to-solvent contrast, we employed phase plate contrast to mitigate the impaired protein visibility. Assisted by phase plate imaging, we obtained a canonical three-arm IgG structure with other structures displaying variable arm densities co-existing in solution, affirming high flexibility of arm-connecting linkers. Furthermore, we showed phase plate imaging enables reliable structure determination of Fab to sub-nanometer resolution from ab initio, yielding a characteristic two-lobe structure that could be unambiguously docked with crystal structure. Our findings revealed conformation diversity of IgG and demonstrated phase plate was viable for cryo-EM analysis of small proteins without symmetry. This work helps extend cryo-EM boundaries, providing a valuable imaging and structural analysis framework for macromolecules with similar challenging features.


Assuntos
Microscopia Crioeletrônica , Fragmentos Fab das Imunoglobulinas , Imunoglobulina G , Conformação Proteica , Microscopia Crioeletrônica/métodos , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/ultraestrutura , Imunoglobulina G/química , Rituximab/química , Humanos , Modelos Moleculares
2.
Artigo em Inglês | MEDLINE | ID: mdl-38698748

RESUMO

AIMS: This study investigates the impact of IbACP (Ipomoea batatas anti-cancer peptide) on defense-related gene expression in tomato leaves, focusing on its role in plant defense mechanisms. BACKGROUND: Previously, IbACP was isolated from sweet potato leaves, and it was identified as a peptide capable of inducing an alkalinization response in tomato suspension culture media. Additionally, IbACP was found to regulate the proliferation of human pancreatic adenocarcinoma cells. OBJECTIVE: Elucidate IbACP's molecular influence on defense-related gene expression in tomato leaves using next-generation sequencing analysis. METHOD: To assess the impact of IbACP on defense-related gene expression, transcriptome data were analyzed, encompassing various functional categories such as photosynthesis, metabolic processes, and plant defense. Semi-quantitative reverse-transcription polymerase chain reaction analysis was employed to verify transcription levels of defense-related genes in tomato leaves treated with IbACP for durations ranging from 0 h (control) to 24 h. RESULTS: IbACP induced jasmonic acid-related genes (LoxD and AOS) at 2 h, with a significant up-regulation of salicylic acid-dependent gene NPR1 at 24 h. This suggested a temporal antagonistic effect between jasmonic acid and salicylic acid during the early hours of IbACP treatment. Downstream ethylene-responsive regulator genes (ACO1, ETR4, and ERF1) were consistently down-regulated by IbACP at all times. Additionally, IbACP significantly up-regulated the gene expressions of suberization-associated anionic peroxidases (TMP1 and TAP2) at all time points, indicating enhanced suberization of the plant cell wall to prevent pathogen invasion. CONCLUSION: IbACP enhances the synthesis of defense hormones and up-regulates downstream defense genes, improving the plant's resistance to biotic stresses.

3.
Nanomedicine (Lond) ; 18(16): 1045-1059, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37610004

RESUMO

Background: The use of nanodiamonds (NDs) and fluorescent nanodiamonds (FNDs) as nonallergenic biocompatible additives in incomplete Freund's adjuvant (IFA) to elicit immune responses in vivo was investigated. Methods: C57BL/6 mice were immunized with chicken egg ovalbumin (OVA) in IFA and also OVA-conjugated NDs (or OVA-conjugated FNDs) in IFA to produce antibodies. OVA-expressing E.G7 lymphoma cells and OVA-negative EL4 cells were inoculated in mice to induce tumor formation. Results: The new formulation significantly enhanced immune responses and thus disease resistance. It exhibited specific therapeutic activities, effectively inhibiting the growth of E.G7 tumor cells in mice over 35 days. Conclusion: The high biocompatibility and multiple functionalities of NDs/FNDs render them applicable as active and trackable vaccine adjuvants and antitumor agents.


Assuntos
Nanodiamantes , Animais , Camundongos , Camundongos Endogâmicos C57BL , Emulsões , Ovalbumina , Corantes , Vacinação
4.
Biol. Res ; 56: 7-7, 2023. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1429908

RESUMO

BACKGROUND: The distinct arterial and venous cell fates are dictated by a combination of various genetic factors which form diverse types of blood vessels such as arteries, veins, and capillaries. We report here that YULINK protein is involved in vasculogenesis, especially venous formation. METHODS: In this manuscript, we employed gene knockdown, yeast two-hybrid, FLIM-FRET, immunoprecipitation, and various imaging technologies to investigate the role of YULINK gene in zebrafish and human umbilical vein endothelial cells (HUVECs). RESULTS: Knockdown of YULINK during the arterial-venous developmental stage of zebrafish embryos led to the defective venous formation and abnormal vascular plexus formation. Knockdown of YULINK in HUVECs impaired their ability to undergo cell migration and differentiation into a capillary-like tube formation. In addition, the phosphorylated EPHB4 was decreased in YULINK knockdown HUVECs. Yeast two-hybrid, FLIM-FRET, immunoprecipitation, as well as imaging technologies showed that YULINK colocalized with endosome related proteins (EPS15, RAB33B or TICAM2) and markers (Clathrin and RHOB). VEGF-induced VEGFR2 internalization was also compromised in YULINK knockdown HUVECs, demonstrating to the involvement of YULINK. CONCLUSION: This study suggests that YULINK regulates vasculogenesis, possibly through endocytosis in zebrafish and HUVECs. Key points Knockdown of YULINK with morpholino in embryos of double transgenic zebrafish exhibited abnormal venous formation. Tube formation and phosphorylated EPHB4 were decreased in YULINK knockdown HUVECs. FLIM-FRET, immunoprecipitation, as well as other imaging technologies showed that YULINK colocalized with endosome related proteins (EPS15, RAB33B and TICAM2) and endosome markers (Clathrin and RHOB). Knockdown of YULINK decreased the internalization of VEGF and VEGFR2 in HUVECs.


Assuntos
Humanos , Animais , Saccharomyces cerevisiae , Peixe-Zebra/genética , Diferenciação Celular , Movimento Celular , Neovascularização Fisiológica , Células Endoteliais da Veia Umbilical Humana
5.
Sci Rep ; 12(1): 21139, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36477410

RESUMO

Coriander (Coriandrum sativum L.) contains abundant antioxidants and essential oils which can provide antibacterial, antifungal, and antioxidant activities in the pharmaceutical, health and food production industry. To improve the economic values of coriander, the relationships between optimal light treatments for maximizing both plant growth and the antioxidant and essential oil content of coriander leaves need to be determined. Plants were exposed to five light-emitting diodes spectral color mixtures, high blue light (BL) intensity induced the levels of reducing power response. The light treatments were then adjusted for the analysis of secondary metabolite compounds of coriander leaves. Among 30 identified compounds, the amounts of decamethyl-cyclopentasiloxane and dodecane were significantly reduced in the R80 + G50 + B50 condition, whereas dodecamethyl-cyclohexasiloxane level was significantly reduced in R50 + G50 + B80 condition. Various light quality and intensity combinations influenced the accumulations of chlorophyll and phytochemical contents, mediated antioxidative properties, and secondary metabolites of coriander leaves, which may be useful in developing a new LED lighting apparatus optimized for coriander production in plant factories.


Assuntos
Coriandrum , Antioxidantes
6.
Bioeng Transl Med ; 7(2): e10285, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35600645

RESUMO

Monocytes are important regulators for the maintenance of homeostasis in innate and adaptive immune system and have been reported to play important role in cancer progression. CD47-SIRPα recognition is a coinhibitory immune signal to inhibit phagocytosis in monocytes and macrophages and has been well-known as the "Don't eat me" signal. By using an approach of integrated sensing and activating proteins (iSNAPs), we have rewired the CD47-SIRPα axis to create iSNAP-M which activates pathways in engineered human monocytes (iSNAP-MC). The mRNA expression levels of the monocyte/macrophage markers CD11b, CD14, and CD31 are upregulated in iSNAP-monocytes (iSNAP-MC). With PMA induction, the iSNAP-MC-derived macrophages (iSNAP-MΦ) showed upregelation in CD86 and CD80, but not CD206. TNFα expression and secretion were also increased in iSNAP-MΦ. Furthermore, the injection of iSNAP-MC into mice bearing human B-lymphoma tumors led to the suppression of tumor progression. Therefore, the engineered monocytes, via blockage of coinhibitory immune signals by rewiring CD47-SIRPα axis, can be applied to suppress target tumors for cancer immunotherapy.

7.
BMC Biol ; 19(1): 214, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34560855

RESUMO

BACKGROUND: Yeast one-hybrid (Y1H) is a common technique for identifying DNA-protein interactions, and robotic platforms have been developed for high-throughput analyses to unravel the gene regulatory networks in many organisms. Use of these high-throughput techniques has led to the generation of increasingly large datasets, and several software packages have been developed to analyze such data. We previously established the currently most efficient Y1H system, meiosis-directed Y1H; however, the available software tools were not designed for processing the additional parameters suggested by meiosis-directed Y1H to avoid false positives and required programming skills for operation. RESULTS: We developed a new tool named GateMultiplex with high computing performance using C++. GateMultiplex incorporated a graphical user interface (GUI), which allows the operation without any programming skills. Flexible parameter options were designed for multiple experimental purposes to enable the application of GateMultiplex even beyond Y1H platforms. We further demonstrated the data analysis from other three fields using GateMultiplex, the identification of lead compounds in preclinical cancer drug discovery, the crop line selection in precision agriculture, and the ocean pollution detection from deep-sea fishery. CONCLUSIONS: The user-friendly GUI, fast C++ computing speed, flexible parameter setting, and applicability of GateMultiplex facilitate the feasibility of large-scale data analysis in life science fields.


Assuntos
Saccharomyces cerevisiae , Análise de Dados , Redes Reguladoras de Genes , Robótica , Saccharomyces cerevisiae/genética , Software
8.
Molecules ; 26(7)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33804903

RESUMO

Sweet potato (Ipomoea batatas) is one of the most important food crops worldwide and its leaves provide a dietary source of nutrients and various bioactive compounds. These constituents of sweet potato leaves (SPL) vary among varieties and play important roles in treating and preventing various diseases. Recently, more attentions in health-promoting benefits have led to several in vitro and in vivo investigations, as well as the identification and quantification of bioactive compounds in SPL. Among them, many new compounds have been reported as the first identified compounds from SPL with their dominant bioactivities. This review summarizes the current knowledge of the bioactive compositions of SPL and their health benefits. Since SPL serve as a potential source of micronutrients and functional compounds, they can be further developed as a sustainable crop for food and medicinal industries.


Assuntos
Antioxidantes/química , Produtos Agrícolas/química , Ipomoea batatas/química , Compostos Fitoquímicos/química , Folhas de Planta/química , Antioxidantes/uso terapêutico , Compostos Fitoquímicos/uso terapêutico
9.
Plant Sci ; 305: 110849, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33691955

RESUMO

IbACP, Ipomoea batatas anti-cancer peptide, a sixteen-amino-acid peptide isolated from sweet potato leaves, is capable of mediating a rapid alkalinization of growth media in plant suspension cells. However, the biological roles of IbACP as a defense peptide have not been studied. The objective of this study was to investigate the effect of IbACP on the accumulation of reactive oxygen species (ROS) and the expression of the defense-related genes. IbACP treatment of sweet potato leaves resulted in marked accumulation of both superoxide ion (O2-) and hydrogen peroxide (H2O2). The activity of peroxidase (POD) was significantly enhanced by IbACP treatment, suggesting that high levels of POD antioxidant activity may be used to scavenge the excess H2O2 in sweet potato plants. The IbACP-related genes were identified by suppression subtractive hybridization (SSH), and were then classified and assigned to the following categories: defense, development, metabolism, signaling, gene expression, and abiotic stress. H2O2 acts as a second messenger for gene activation in some of the IbACP-triggered gene expressions. These results demonstrated that IbACP is part of an integrated strategy for genetic regulation in sweet potato. Our work highlights the function of IbACP and its potential use for enhancing stress tolerance in sweet potato, in an effort to improve our understanding of defense-response mechanisms.


Assuntos
Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Peptídeos/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Ipomoea batatas/química , Folhas de Planta/química , Proteínas de Plantas/genética
10.
Arch Physiol Biochem ; 127(1): 82-89, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31112046

RESUMO

BACKGROUND: Cardio-dysfunction is one of the complications in patients with diabetes mellitus (DM). This paper aimed to investigate if oral administration of green tea Epigallocatechin-3-gallate (EGCG, E) and transplantation of adipose-derived stem cells (ADSC) show cross effects on the treatment of cardiomyopathy in rats with type 1 DM. MATERIALS AND METHODS: Wistar male rats were divided into four groups (each group contained 8 animals) including sham, DM (diabetic group), DM + ADSC (DM group with ADSC treatment) and DM + ADSC + E (DM + ADSC group with oral administration of EGCG). RESULTS: Pathological parameters including hypertrophy, inflammation, and fibrosis were activated in DM group. By contrast, all parameters were significantly improved in treatment group (DM + ADSC group). In addition, improvement of pathological parameters in DM + ADSC + E was significantly better than DM + ADSC. CONCLUSION: We found that EGCG can increase expression of survival marker in ADSC under high glucose environment and reduce serum oxidative stress in DM rats.


Assuntos
Adipócitos/efeitos dos fármacos , Cardiomiopatias/tratamento farmacológico , Catequina/análogos & derivados , Estresse Oxidativo , Células-Tronco/efeitos dos fármacos , Chá , Adipócitos/citologia , Tecido Adiposo/efeitos dos fármacos , Administração Oral , Animais , Glicemia/metabolismo , Catequina/farmacologia , Diabetes Mellitus Experimental , Ecocardiografia , Inflamação , Masculino , Ratos , Ratos Wistar , Transplante de Células-Tronco , Células-Tronco/citologia , Transplante Autólogo
11.
J Microbiol Immunol Infect ; 54(4): 616-626, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32127288

RESUMO

BACKGROUND: Salmonella enterica serovar Typhimurium, a non-typhoidal food-borne pathogen, causes acute enterocolitis, bacteremia, extraintestinal focal infections in humans. Salmonella pathogenicity islands 1 and 2 (SPI-1 and SPI-2) contribute to invading into host cellular cytosol, residing in Salmonella-containing vacuoles for intracellular survival, and inducing cellular apoptosis. This study aimed to better understand the mechanism underlying apoptosis in Salmonella-infected macrophages. METHODS: S. Typhimurium SL1344 was used to evaluate extrinsic and intrinsic apoptosis pathways in THP-1 monocyte-derived macrophages in response to Salmonella infection. RESULTS: Activated caspase-3-induced apoptosis pathways, including extrinsic (caspase-8-mediated) and intrinsic (caspase-9-mediated) pathways, in Salmonella-infected macrophages were verified. THP-1 cells with dysfunction of TLR-4 and TLR-5 and Salmonella SPI-1 and SPI-2 mutants were constructed to identify the roles of the genes associated with programmed cell death in the macrophages. Caspase-3 activation in THP-1 macrophages was induced by Salmonella through TLR-4 and TLR-5 signaling pathways. We also identified that SPI-1 structure protein PrgH and effectors SipB and SipD, but not SPI-2 structure protein SsaV, could induce apoptosis via caspase-3 activation and reduce the secretion of inflammation marker TNF-α in the Salmonella-infected cells. The two effectors also reduced the translocation of the p65 subunit of NF-κB into the nucleus and the expression of TNF-α, and then inflammation was diminished. CONCLUSION: Non-typhoid Salmonella induced apoptosis of macrophages and thereby reduced inflammatory cytokine production through the expression of SPI-1. This mechanism in host-pathogen interaction may explain why Salmonella usually manifests as occult bacteremia with less systemic inflammatory response syndrome in the bloodstream infection of children.


Assuntos
Apoptose , Ilhas Genômicas/genética , Interações Hospedeiro-Patógeno , Macrófagos/microbiologia , Macrófagos/patologia , Salmonella typhimurium/genética , Caspase 3/genética , Caspase 3/imunologia , Linhagem Celular , Citocinas/genética , Citocinas/imunologia , Humanos , Inflamação , Macrófagos/imunologia , Salmonella typhimurium/imunologia , Salmonella typhimurium/patogenicidade , Células THP-1 , Virulência
12.
Microb Pathog ; 146: 104222, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32387390

RESUMO

Inflammasome activation is an important host response to infectious diseases, but the difference in inflammasome activation between typhoid fever and non-typhoidal Salmonella infection has been rarely studied. To determine whether inflammasome activation in macrophages after S. Typhi and S. Typhimurium infection is different, we measured pyroptosis, caspase-1 activation, and IL-1ß secretion in monocyte-derived macrophages infected with S. Typhi or S. Typhimurium both in vitro and ex vivo. The role of Vi capsule and virulence genes in Salmonella pathogenicity island-1 (SPI-1), belonging to type III secretion system, was also examined. S. Typhi caused more pyroptosis, caspase-1 activation, and IL-1ß production than S. Typhimurium did, predominantly within 2 h of infection, in the context of high number of infecting bacteria. Mutagenesis and complementation experiments confirmed that SPI-1 effectors but not Vi were associated with greater inflammasome activation. The expression levels of invA and hilA were significantly higher in S. Typhi than in S. Typhimurium at early log phase in SPI-1 environment. Thus, S. Typhi, relative to its non-typhoidal counterpart, S. Typhimurium, induces greater SPI-1-dependent inflammasome activation in monocyte-derived macrophages. This finding may explain why S. Typhi causes a hyperinflammatory state at bacteremic stage in typhoid fever.


Assuntos
Salmonella typhi/patogenicidade , Sistemas de Secreção Tipo III , Proteínas de Bactérias/genética , Caspase 1/metabolismo , Expressão Gênica , Ilhas Genômicas/genética , Humanos , Inflamassomos/metabolismo , Inflamação/etiologia , Inflamação/microbiologia , Interleucina-1beta/metabolismo , Macrófagos/microbiologia , Macrófagos/patologia , Polissacarídeos Bacterianos/genética , Cultura Primária de Células , Salmonella typhi/genética , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidade , Células THP-1 , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo , Febre Tifoide/etiologia , Febre Tifoide/microbiologia , Virulência/genética , Fatores de Virulência/genética
13.
Sci Rep ; 9(1): 13164, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511584

RESUMO

Since its discovery nearly a century ago, antibiotics has been one of the most effective methods in treating infectious diseases and limiting pathogen spread. However, pathogens often build up antibiotic resistance over time, leading to serious failure of the treatment. Silver nanoparticle (AgNP) is an appealing alternative, but successful treatment of the bacterial infection requires a plentiful supply of AgNP, which can negatively impact human health if people are excessively exposed to the particles. Here, we present a method to overcome this challenge by synthesizing nanodiamond-supported AgNP noncovalently conjugated with albumin molecules to achieve enhanced antibacterial activity and strengthened biocompatibility. Using Escherichia coli as a model bacterium, we found that the albumin-conjugated silver-diamond nanohybrids showed a long-term bactericidal effect after 36 days of the treatment at the AgNP concentration of 250 µg mL-1. Moreover, the toxicity of the nanohybrids to human cells (including human fibroblasts, lung adenocarcinoma epithelial cells, and breast adenocarcinoma cells) is low even at the particle concentration of 500 µg mL-1. The method provides a general and practical solution to the concerns of bacterial resistance against AgNP and issues associated with the size, shape, aggregation, and toxicity of AgNP are largely resolved. Finally, we demonstrate that the nanohybrids can be readily incorporated into natural polysaccharides (such as guar gum) to form three-in-one hydrogels, showing promising applications in nanomedicine.


Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Nanopartículas Metálicas/química , Nanodiamantes/química , Prata/química , Células A549 , Albuminas/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Células MCF-7 , Nanopartículas Metálicas/ultraestrutura , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Nanodiamantes/ultraestrutura , Tamanho da Partícula
14.
Bioconjug Chem ; 30(8): 2228-2237, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31268690

RESUMO

Delivering functional proteins (such as enzymes) into cells is important in various biological studies and is often accomplished indirectly by transfection with DNA or mRNA encoding recombinant proteins. However, the transfection efficiency of conventional plasmid methods is low for primary cells, which are crucial sources of cell therapy. Here, we present a new platform based on the use of fluorescent nanodiamond (FND) as a biocompatible nanocarrier to enable rapid, effective, and homogeneous labeling of human mesenchymal stem cells (MSCs) with luciferase for multiplex assays and ultrasensitive detection. More than 100 pg of FND and 100 million copies of firefly luciferase can be delivered into each MSC through endocytosis. Moreover, these endocytic luciferase molecules are catalytically active for hours, allowing the cells to be imaged and tracked in vitro as well as in vivo by both fluorescence and bioluminescence imaging. Our results demonstrate that luciferase-conjugated FNDs are useful as multifunctional labels of human stem cells for diverse theranostic applications.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Luciferases/administração & dosagem , Imagem Multimodal/métodos , Nanodiamantes/uso terapêutico , Células-Tronco/metabolismo , Fluorescência , Humanos , Luciferases/metabolismo , Células-Tronco Mesenquimais/metabolismo , Nanomedicina Teranóstica
15.
Small ; 11(34): 4394-402, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26077637

RESUMO

Quiescent cancer stem cells (CSCs) have long been considered to be a source of tumor initiation. However, identification and isolation of these cells have been hampered by the fact that commonly used fluorescent markers are not sufficiently stable, both chemically and photophysically, to allow tracking over an extended period of time. Here, it is shown that fluorescent nanodiamonds (FNDs) are well suited for this application. Genotoxicity tests of FNDs with comet and micronucleus assays for human fibroblasts and breast cancer cells indicate that the nanoparticles neither cause DNA damage nor impair cell growth. Using AS-B145-1R breast cancer cells as the model cell line for CSC, it is found that the FND labeling outperforms 5-ethynyl-2'-deoxyuridine (EdU) and carboxyfluorescein diacetate succinimidyl ester (CFSE) in regards to its long-term tracking capability (>20 d). Moreover, through a quantification of their stem cell activity by measuring mammosphere-forming efficiencies (MFEs) and self-renewal rates, the FND-positive cells are identified to have an MFE twice as high as that of the FND-negative cells isolated from the same dissociated mammospheres. Thus, the nanoparticle-based labeling technique provides an effective new tool for tracking and finding slow-proliferating/quiescent CSCs in cancer research.


Assuntos
Ciclo Celular , Rastreamento de Células/métodos , Nanodiamantes/química , Células-Tronco Neoplásicas/patologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Citometria de Fluxo , Fluorescência , Humanos , Microscopia Confocal , Mutagênicos/toxicidade , Células-Tronco Neoplásicas/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/patologia
16.
Toxicol Lett ; 234(1): 20-9, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25668154

RESUMO

Higher serum level of p-cresol (PC) in chronic kidney disease (CKD) patients has been linked with CKD progression. The toxic effect of PC on diverse cells has been reported by prior studies, except for renal tubular cells. Both autophagy and apoptosis contribute to renal tubular cell death, yet evidence of its response to PC is limited and their crosstalk is still unclear. Autophagy is an important cellular process involved in toxin-induced cell death. Renal tubular cell death in tubular injury is thought to be one of the key events causing the progression of CKD. Thus, we treated rat (NRK-52E) and human (HRPTEC) renal proximal tubular cells (RPTC) with PC and found the cell proliferation was significantly decreased. Cell apoptosis was significantly increased and accompanied with the activation of autophagy as evidenced by increases in LC3-II, beclin 1 and Atg 4. We also found an increase of p62 by c-Jun activation. p62 accumulation could mediate the activation of caspase 8-dependent cell apoptosis. Conversely, knockdown of p62 by siRNA of p62 had the opposite effect by arresting LC3-II accumulation and promoting increasing cell viability. We conclude that PC triggered autophagic RPTC death via JNK-mediated p62 accumulation and then activated caspase 8-dependent cell death pathway. PC can be considered as one of the key events causing progression of CKD, which might affect drug disposition in CKD cases.


Assuntos
Cresóis/toxicidade , Túbulos Renais Proximais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/análise , Autofagia/efeitos dos fármacos , Proteína Beclina-1 , Caspase 8/análise , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais , Citometria de Fluxo , Proteínas de Choque Térmico/análise , Humanos , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/metabolismo , Microscopia de Fluorescência , Ratos , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Proteína Sequestossoma-1
17.
PLoS One ; 8(12): e84443, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24358361

RESUMO

Classical swine fever (CSF), foot-and-mouth disease (FMD) and porcine reproductive and respiratory syndrome (PRRS) are the primary diseases affecting the pig industry globally. Vaccine induced CD8(+) T cell-mediated immune response might be long-lived and cross-serotype and thus deserve further attention. Although large panels of synthetic overlapping peptides spanning the entire length of the polyproteins of a virus facilitate the detection of cytotoxic T lymphocyte (CTL) epitopes, it is an exceedingly costly and cumbersome approach. Alternatively, computational predictions have been proven to be of satisfactory accuracy and are easily performed. Such a method enables the systematic identification of genome-wide CTL epitopes by incorporating epitope prediction tools in analyzing large numbers of viral sequences. In this study, we have implemented an integrated bioinformatics pipeline for the identification of CTL epitopes of swine viruses including the CSF virus (CSFV), FMD virus (FMDV) and PRRS virus (PRRSV) and assembled these epitopes on a web resource to facilitate vaccine design. Identification of epitopes for cross protections to different subtypes of virus are also reported in this study and may be useful for the development of a universal vaccine against such viral infections among the swine population. The CTL epitopes identified in this study have been evaluated in silico and possibly provide more and wider protection in compared to traditional single-reference vaccine design. The web resource is free and open to all users through http://sb.nhri.org.tw/ICES.


Assuntos
Antígenos Virais/imunologia , Vírus da Febre Suína Clássica/imunologia , Epitopos de Linfócito T/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Antígenos Virais/química , Antígenos Virais/genética , Peste Suína Clássica/prevenção & controle , Vírus da Febre Suína Clássica/genética , Mapeamento de Epitopos , Epitopos de Linfócito T/química , Epitopos de Linfócito T/genética , Genoma Viral , Dados de Sequência Molecular , Suínos , Vacinas Virais/imunologia
18.
Peptides ; 47: 148-56, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23428969

RESUMO

A 16-amino-acid peptide was isolated from the leaves of sweet potato. The peptide caused a rapid alkalinization response in tomato suspension culture media, a characteristic of defense peptides in plants. No post-translational modification was observed on the peptide according to MALDI-MS analysis. We have named the peptide Ipomoea batatas anti-cancer peptide (IbACP). IbACP also was shown with the ability to dose-dependently inhibit Panc-1, a pancreatic cancer line, cell proliferation. The morphological observations of the Panc-1 cells by phase contrast microscopy showed significant changes after treatment with IbACP. Moreover, caspase-3 and PARP [poly(ADP-ribose) polymerase] were activated by IbACP treatment, followed by cell death. An increase in the levels of cleaved caspase-3 and -9 was also detected by an immunoblot assay after treatment with IbACP. In addition, genomic DNA fragmentation and decreased cellular proliferation were induced when IbACP was supplied to the Panc-1 cells, further demonstrating its biological relevance. The combined data indicates that IbACP peptide may have an important role in the regulation of cellular proliferation by inducing and promoting apoptosis through the mitochondrial apoptotic pathway. This report also showed that IbACP peptide contains potent anti-cancer effects and may play an important role in herbal medicine development.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ipomoea batatas/química , Extratos Vegetais/química , Folhas de Planta/química , Proteínas de Plantas/farmacologia , Sequência de Aminoácidos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Caspases/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA , Expressão Gênica/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação
19.
New Phytol ; 196(2): 427-440, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22931461

RESUMO

MicroRNAs (miRNAs) are small noncoding RNAs which post-transcriptionally regulate gene expression by directing mRNA cleavage or translational inhibition. miRNAs play multiple roles in the growth, development and stress responses in plants. However, little is known of the wounding-responsive miRNAs and their regulation. Here, we investigated the expression patterns of microR828 (miR828) on wounding in sweet potato (Ipomoea batatas cv Tainung 57). The expression of miR828 was only detected in leaves, and was induced by wounding rather than by ethylene, hydrogen peroxide (H2O2), methyl jasmonate or nitric oxide (NO). Moreover, cyclic guanosine monophosphate (cGMP) was necessary for miR828 accumulation in leaves on wounding. Two miR828 target candidates, named IbMYB and IbTLD, were obtained by cDNA cloning, and their mRNA cleavage caused by miR828 was confirmed by cleavage site mapping, agro-infiltration and transgenics studies. The reduction in IbMYB and IbTLD expression coincided with the induction of miR828, demonstrating that IbMYB and IbTLD might be miR828 targets. Furthermore, transgenic sweet potato overexpressing miR828 precursor affected lignin and H2O2 contents. These results showed that cGMP could regulate wounding-responsive miR828, which repressed the expression of IbMYB and IbTLD. Subsequently, lignin and H2O2 were accumulated to participate in defense mechanisms.


Assuntos
Peróxido de Hidrogênio/metabolismo , Ipomoea batatas/metabolismo , Lignina/metabolismo , MicroRNAs/metabolismo , Estresse Mecânico , Acetatos/farmacologia , Agrobacterium/efeitos dos fármacos , Agrobacterium/metabolismo , Antioxidantes/metabolismo , Sequência de Bases , Cálcio/metabolismo , ADP-Ribose Cíclica/metabolismo , GMP Cíclico/metabolismo , Ciclopentanos/farmacologia , Etilenos/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ipomoea batatas/efeitos dos fármacos , Ipomoea batatas/enzimologia , Ipomoea batatas/genética , MicroRNAs/química , MicroRNAs/genética , Dados de Sequência Molecular , Niacinamida/farmacologia , Óxido Nítrico/metabolismo , Ácido Okadáico/farmacologia , Oxilipinas/farmacologia , Fosfoproteínas Fosfatases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Propanóis/metabolismo , Proteínas Quinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estaurosporina/farmacologia
20.
Intern Med ; 51(9): 1015-21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22576379

RESUMO

OBJECTIVE: To analyze the incidence rates and risk factors for bacteremia in patients undergoing hemodialysis (HD) and peritoneal dialysis (PD). METHODS: The records of 898 consecutive patients undergoing dialysis from January 2003 to December 2008 were reviewed retrospectively. Episodes of bacteremia were recorded. China Medical University (Taichung, Taiwan). RESULTS: The overall incidence rate of bacteremia was 7.63 per 100 patient-years in HD patients and 3.56 per 100 patient-years in PD patients and it was higher in HD patients each year from 2003 to 2008. S. aureus (27.53%) was the most common pathogen in HD patients, whereas Coagulase-negative Staphylococcus (21.3%) was the most common pathogen in PD patients. Vascular access infection was the most common etiology in HD patients, whereas peritonitis was the most common etiology in PD patients. Older age, shorter dialysis vintage, use of HD rather than PD, current smoker, use of a venous dialysis catheter, presence of diabetes mellitus, higher comorbidity score, and lower serum albumin were significant risk factors for bacteremia. Diabetes mellitus and lower serum albumin were significant risk factors for bacteremia-associated mortality. CONCLUSION: Placement of a permanent access (fistula, graft, or PD catheter) prior to initiation of dialysis, smoking cessation, and better nutritional status (i.e. higher serum albumin) were associated with a reduced risk of bacteremia in dialysis patients. Higher serum albumin was also associated with a reduced bacteremia-associated mortality.


Assuntos
Bacteriemia/epidemiologia , Diálise Peritoneal/efeitos adversos , Diálise Renal/efeitos adversos , Adulto , Idoso , Bacteriemia/sangue , Bacteriemia/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
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