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1.
J Transl Med ; 22(1): 604, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951906

RESUMEN

BACKGROUND: Triple-negative breast cancer (TNBC) is a recurrent, heterogeneous, and invasive form of breast cancer. The treatment of TNBC patients with paclitaxel and fluorouracil in a sequential manner has shown promising outcomes. However, it is challenging to deliver these chemotherapeutic agents sequentially to TNBC tumors. We aim to explore a precision therapy strategy for TNBC through the sequential delivery of paclitaxel and fluorouracil. METHODS: We developed a dual chemo-loaded aptamer with redox-sensitive caged paclitaxel for rapid release and non-cleavable caged fluorouracil for slow release. The binding affinity to the target protein was validated using Enzyme-linked oligonucleotide assays and Surface plasmon resonance assays. The targeting and internalization abilities into tumors were confirmed using Flow cytometry assays and Confocal microscopy assays. The inhibitory effects on TNBC progression were evaluated by pharmacological studies in vitro and in vivo. RESULTS: Various redox-responsive aptamer-paclitaxel conjugates were synthesized. Among them, AS1411-paclitaxel conjugate with a thioether linker (ASP) exhibited high anti-proliferation ability against TNBC cells, and its targeting ability was further improved through fluorouracil modification. The fluorouracil modified AS1411-paclitaxel conjugate with a thioether linker (FASP) exhibited effective targeting of TNBC cells and significantly improved the inhibitory effects on TNBC progression in vitro and in vivo. CONCLUSIONS: This study successfully developed fluorouracil-modified AS1411-paclitaxel conjugates with a thioether linker for targeted combination chemotherapy in TNBC. These conjugates demonstrated efficient recognition of TNBC cells, enabling targeted delivery and controlled release of paclitaxel and fluorouracil. This approach resulted in synergistic antitumor effects and reduced toxicity in vivo. However, challenges related to stability, immunogenicity, and scalability need to be further investigated for future translational applications.


Asunto(s)
Aptámeros de Nucleótidos , Preparaciones de Acción Retardada , Liberación de Fármacos , Fluorouracilo , Nucleolina , Paclitaxel , Fosfoproteínas , Proteínas de Unión al ARN , Neoplasias de la Mama Triple Negativas , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Aptámeros de Nucleótidos/farmacología , Aptámeros de Nucleótidos/química , Humanos , Paclitaxel/uso terapéutico , Paclitaxel/farmacología , Línea Celular Tumoral , Animales , Femenino , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Proteínas de Unión al ARN/metabolismo , Fosfoproteínas/metabolismo , Oligodesoxirribonucleótidos/farmacología , Oligodesoxirribonucleótidos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto , Proliferación Celular/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Ratones Endogámicos BALB C
2.
Medicine (Baltimore) ; 103(6): e37234, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38335402

RESUMEN

China has become an emerging destination for international migration, especially in some Association of South East Asian Nations countries, but the situation of migrants seeking medical care in China remains unclear. A retrospective cross-sectional study was conducted in a hospital in Chongzuo, which provides medical services for foreigners, to investigate the situation of Vietnamese people seeking health care in Guangxi, China. Vietnamese patients who visited the hospital between 2018 and 2020 were included in the study. Demographic characteristics, clinical characteristics, characteristics of payment for medical costs, and characteristics of hospitalization were compared between outpatients and inpatients. In total, 778 Vietnamese outpatients and 173 inpatients were included in this study. The percentages of female outpatients and inpatients were 93.44% and 88.44% (χ2 = 5.133, P = .023), respectively. Approximately 30% of outpatients and 47% of inpatients visited the hospital due to obstetric needs. The proportions of outpatients with basic medical insurance for urban residents, basic medical insurance for urban employees, and new cooperative medical schemes were 28.02%, 3.21%, and 2.31%, respectively. In comparison, the proportion of inpatients with the above 3 types of medical insurance was 16.76%, 1.73%, and 2.31%, respectively. The proportion of different payments for medical costs between outpatients and inpatients were significantly different (χ2 = 24.404, P < .01). Middle-aged Vietnamese females in Guangxi, China, may have much greater healthcare needs. Their main medical demand is for obstetric services. Measurements should be taken to improve the health services targeting Vietnamese female, but the legitimacy of Vietnamese in Guangxi is a major prerequisite for them to access more and better healthcare services.


Asunto(s)
Emigración e Inmigración , Necesidades y Demandas de Servicios de Salud , Seguro de Salud , Obstetricia , Pueblos del Sudeste Asiático , Femenino , Humanos , Persona de Mediana Edad , China/epidemiología , Estudios Transversales , Seguro de Salud/estadística & datos numéricos , Estudios Retrospectivos , Pueblos del Sudeste Asiático/etnología , Pueblos del Sudeste Asiático/estadística & datos numéricos , Vietnam/etnología , Necesidades y Demandas de Servicios de Salud/economía , Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Migrantes/estadística & datos numéricos , Emigración e Inmigración/estadística & datos numéricos , Obstetricia/economía , Obstetricia/estadística & datos numéricos , Aceptación de la Atención de Salud , Accesibilidad a los Servicios de Salud/estadística & datos numéricos
3.
Diabetes Obes Metab ; 26(5): 1593-1604, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38302734

RESUMEN

AIM: To provide a systematic overview of diabetes risk prediction models used for prediabetes screening to promote primary prevention of diabetes. METHODS: The Cochrane, PubMed, Embase, Web of Science and China National Knowledge Infrastructure (CNKI) databases were searched for a comprehensive search period of 30 August 30, 2023, and studies involving diabetes prediction models for screening prediabetes risk were included in the search. The Quality Assessment Checklist for Diagnostic Studies (QUADAS-2) tool was used for risk of bias assessment and Stata and R software were used to pool model effect sizes. RESULTS: A total of 29 375 articles were screened, and finally 20 models from 24 studies were included in the systematic review. The most common predictors were age, body mass index, family history of diabetes, history of hypertension, and physical activity. Regarding the indicators of model prediction performance, discrimination and calibration were only reported in 79.2% and 4.2% of studies, respectively, resulting in significant heterogeneity in model prediction results, which may be related to differences between model predictor combinations and lack of important methodological information. CONCLUSIONS: Numerous models are used to predict diabetes, and as there is an association between prediabetes and diabetes, researchers have also used such models for screening the prediabetic population. Although it is a new clinical practice to explore, differences in glycaemic metabolic profiles, potential complications, and methods of intervention between the two populations cannot be ignored, and such differences have led to poor validity and accuracy of the models. Therefore, there is no recommended optimal model, and it is not recommended to use existing models for risk identification in alternative populations; future studies should focus on improving the clinical relevance and predictive performance of existing models.


Asunto(s)
Diabetes Mellitus , Hipertensión , Estado Prediabético , Humanos , Estado Prediabético/diagnóstico , Estado Prediabético/epidemiología , Estado Prediabético/tratamiento farmacológico , China
4.
Gene ; 885: 147715, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37591325

RESUMEN

Nitrogen (N) is the key essential macronutrient for crop growth and yield. Over-application of inorganic N fertilizer in fields generated serious environmental pollution and had a negative impact to human health. Therefore, improving crop N use efficiency (NUE) is helpful for sustainable agriculture. The biological functions of nitrogen transporters and regulators have been intensively studied in many crop species. However, only a few nitrogen transporters have been identified in tobacco to date. We reported the identification and functional characterization of a nitrate transporter NtNPF2.11 from tobacco (Nicotiana tabacum). qRT-PCR assay revealed that NtNPF2.11 was mainly expressed in leaf and vein. Under middle N (MN, 1.57 kg N/100 m2) and high N (HN, 2.02 kg N/100 m2) conditions, overexpression of NtNPF2.11 in tobacco greatly improved N utilization and biomass. Moreover, under middle N and high N conditions, the expression of genes for nitrate assimilation, such as NtNR1, NtNiR, NtGS and NtGOGAT, were upregulated in NtNPF2.11 overexpression plants. Compared with WT, overexpression of NtNPF2.11 increased potassium (K) accumulation under high N conditions. These results indicated that overexpression of NtNPF2.11 could increase tobacco yield, N and K accumulation under higher N conditions. Overall, these findings improve our understanding the function of NtNPF2.11 and provide useful gene for sustainable agriculture.


Asunto(s)
Nicotiana , Transportadores de Nitrato , Humanos , Nicotiana/genética , Agricultura , Biomasa , Proteínas de Transporte de Membrana/genética , Nitrógeno
5.
J Plant Physiol ; 287: 154048, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37399697

RESUMEN

Drought and salt are major abiotic stresses that severely restricts plant growth and development, leading to serious losses in agricultural production. Therefore, improving crop tolerance to drought and salt stresses is an urgent issue. A previous study showed that overexpression of Arabidopsis NLR gene AtRPS2 conferred broad-spectrum disease resistance in rice. In this study, we demonstrated that constitutive expression of AtRPS2 increased abscisic acid (ABA) sensitivity during seedling stage, the shoot length of transgenic plants were shorter than wild type plants. Exogenous application of ABA markedly induced the expression of stress-related genes and promoted stomatal close in transgenic plants. Overexpression of AtRPS2 also enhanced drought and salt tolerance in rice, transgenic plants exhibited higher survival rates under drought and salt conditions than wild type plants. The activities of catalase (CAT) and superoxide dismutase (SOD) were higher in AtRPS2 transgenic rice than wild type plants. In addition, the expression of stress-related genes and ABA-responsive genes were significantly upregulated in AtRPS2 transgenic plants than wild type plants under drought and salt treatments. Besides, exogenous application of ABA could facilitate drought and salt tolerance in AtRPS2 transgenic plants. Taken together, this study indicated that AtRPS2 could improve drought and salt tolerance in rice, and this phenomenon is likely to be regulated through ABA signaling pathways.


Asunto(s)
Arabidopsis , Oryza , Tolerancia a la Sal/genética , Oryza/genética , Oryza/metabolismo , Leucina/genética , Leucina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sequías , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Arabidopsis/genética , Nucleótidos/metabolismo , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética
6.
Front Oncol ; 13: 1136366, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37064142

RESUMEN

Methods: 83 patients with hepatocellular carcinoma (HCC) admitted to the interventional oncology department were randomly divided into two groups. Apatinib and camrelizumab were administered to 42 patients in group A, whereas sorafenib was administered to 41 patients in group B for three months. The clinical efficacy was evaluated in terms of objective response rate (ORR), and disease control rate (DCR). Certain tumor markers like alpha-fetoprotein (AFP), carbohydrate antigen 199 (CA199), carcinoembryonic antigen (CEA), hypoxia-inducible factor (HIF-1), immune function T lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+) were determined before and after treatment. The serum levels of vascular endothelial growth factor (VEGF), osteopontin (OPN), aspartate aminotransferase (AST), and epidermal growth factor 7 (EGF7)] were observed. The survival time between the two groups was compared, such as progression-free survival (PFS) and median survival (MS). Finally, the toxicity and side effects data were also obtained. Results: The ORR and DCR of group A were 69.05% and 88.10%, respectively, which were significantly higher (P<0.05) than group B (ORR=53.66% and DCR=70.73%). After treatment, the AFP, CA199, CEA, and HIF-1 levels of both groups decreased significantly (P<0.05), and the respective biomarker levels of group A were lower than those of group B (P<0.05). Following treatment, CD3+, CD4+, CD4+/CD8+ index in group A significantly increased (P<0.05) while CD8+ level was significantly decreased (P<0.05). Compared to group B, a significant increase was observed in group A's CD3+, CD4+, and CD4+/CD8+ index. There were no significant changes in CD3+, CD4+, CD8+, CD4+/CD8+ indexes before and after treatment in group B (P>0.05). The serum level of VEGF, OPN, EGF-7 and AST indexes of group A&B were decreased significantly (P<0.05). Compared with group B, the VEGF, OPN, EGF7 and AST indexes of group A were significantly reduced (P<0.05). PFS and MS in group A were significantly higher than in group B (P<0.05). There was no significant difference between groups A and B in terms of toxicity and adverse effects (P>0.05). Conclusion: In treating HCC, combining apatinib and camrelizumab can reduce tumor markers, enhance the immune system and curative effect, and prolong patient survival. The underline mechanism is related to the down-regulation of VEGF, OPN and HIF-1 indexes.

7.
J Control Release ; 353: 792-801, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36493948

RESUMEN

The bioavailability of peptides co-delivered with permeation enhancers following oral administration remains low and highly variable. Two factors that may contribute to this are the dilution of the permeation enhancer in the intestinal fluid, as well as spreading of the released permeation enhancer and peptide in the lumen by intestinal motility. In this work we evaluated an Intestinal Administration Device (IAD) designed to reduce the luminal dilution of drug and permeation enhancer, and to minimize movement of the dosage form in the intestinal lumen. To achieve this, the IAD utilizes an expanding design that holds immediate release mini tablets and places these in contact with the intestinal epithelium, where unidirectional drug release can occur. The expanding conformation limits movement of the IAD in the intestinal tract, thereby enabling drug release at a single focal point in the intestine. A pig model was selected to study the ability of the IAD to promote intestinal absorption of the peptide MEDI7219 formulated together with the permeation enhancer sodium caprate. We compared the IAD to intestinally administered enteric coated capsules and an intestinally administered solution. The IAD restricted movement of the immediate release tablets in the small intestine and histological evaluation of the mucosa indicated that high concentrations of sodium caprate were achieved. Despite significant effect of the permeation enhancer on the integrity of the intestinal epithelium, the bioavailability of MEDI7219 was of the same order of magnitude as that achieved with the solution and enteric coated capsule formulations (2.5-3.8%). The variability in plasma concentrations of MEDI7219 were however lower when delivered using the IAD as compared to the solution and enteric coated capsule formulations. This suggests that dosage forms that can limit intestinal dilution and control the position of drug release can be a way to reduce the absorptive variability of peptides delivered with permeation enhancers but do not offer significant benefits in terms of increasing bioavailability.


Asunto(s)
Mucosa Intestinal , Intestinos , Animales , Porcinos , Mucosa Intestinal/metabolismo , Péptidos/química , Absorción Intestinal , Administración Oral , Comprimidos , Disponibilidad Biológica
8.
Front Cell Dev Biol ; 10: 855474, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35652096

RESUMEN

Pancreatic cancer (PC) is one of the most lethal cancers with an almost 10% 5-year survival rate. Because PC is implicated in high heterogeneity, desmoplastic tumor-microenvironment, and inefficient drug-penetration, the chemotherapeutic strategy currently recommended for the treatment of PC has limited clinical benefit. Nucleic acid-based targeting therapies have become strong competitors in the realm of drug discovery and targeted therapy. A vast evidence has demonstrated that antibody-based or alternatively aptamer-based strategy largely contributed to the elevated drug accumulation in tumors with reduced systematic cytotoxicity. This review describes the advanced progress of antisense oligonucleotides (ASOs), small interfering RNAs (siRNAs), microRNAs (miRNAs), messenger RNA (mRNAs), and aptamer-drug conjugates (ApDCs) in the treatment of PC, revealing the bright application and development direction in PC therapy.

9.
Int J Biol Sci ; 18(3): 1238-1253, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35173550

RESUMEN

Due to the large proportion of BRCA deficiency and chromosomal instability in OS patients, poly (ADP-ribose) polymerase inhibitors (PARPi) could be an effective strategy for anti-OS therapy. In two orthotopic OS mouse models, we discovered that although PARPi had inhibitory effect on the growth of the orthotopic OS tumors regardless of BRCA deficiency, the treatment of PARPi essentially aggravated the pulmonary metastasis of OS in both models. A protein playing a crucial role in OS metastasis, ezrin, was identified as an interactive protein for PARP1. The phosphorylation of ezrin was significantly promoted during PARP inhibition. Besides the traditional function of phosphorylated ezrin at plasma membrane, we newly identified its nuclear speckle localization and its function with mRNA export. Ezrin knockdown or phosphorylation inhibition could partially rescue PARPi induced metastasis. Collectively, we unveiled a new mechanism for PARP-involved OS metastasis, which proposed a novel combinational therapy strategy using PARP and ezrin inhibitors for future OS treatment.


Asunto(s)
Neoplasias Óseas , Neoplasias Pulmonares , Osteosarcoma , Adenosina Difosfato/metabolismo , Animales , Proteínas del Citoesqueleto , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Osteosarcoma/tratamiento farmacológico , Fosforilación , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Ribosa
10.
Biochem Biophys Res Commun ; 583: 1-6, 2021 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-34715495

RESUMEN

Ubiquitination is a pivotal post-translational modification that regulates turnover of nucleotide-binding site and leucine-rich repeat receptors (NLRs). As a RING-type E3 ligase, BOI (Botrytis susceptible1 interactor) has been reported to interact with different proteins, and function in the nucleus. New studies have identified that BOI can interact and ubiquitinate L5 (AT1G12290), a CC-NBS-LRR protein in vitro, and mediate the proteasomal degradation of L5 in Nicotiana benthamiana and Arabidopsis thaliana. However, there still remains an unanswered question about where the degradation occurs at the subcellular level. In this study, the ubiquitination of L5 by BOI was determined in N. benthamiana. Meanwhile, we discovered that BOI exhibited nucleocytoplasmic localization and mediated the degradation of the plasma membrane localized L5 outside the nucleus. BOI and its homologs BRG1 and BRG3 function redundantly in negatively regulate the protein level of L5. Overall, this report reveals BOI and its homologs have multiple targets and function at different subcellular locations.

11.
Biochem Biophys Res Commun ; 578: 104-109, 2021 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-34560579

RESUMEN

Nucleotide-binding site and leucine-rich repeat receptors (NLRs) play pivotal roles in plant immunity. The regulation of NLR stability is essential to ensure effective immunity, whereas the exact mechanism is largely unclear. The Arabidopsis CC-NBS-LRR protein L5 (At1g12290) can induce cell death in Nicotiana benthamiana, but not in Arabidopsis thaliana. We screened the interactors of L5 by yeast two-hybrid, and found that the BOI can interact with the CC domain of L5. Transiently expressed BOI reduced the protein level of L5, and suppressed the auoactivity of L5 in N. benthamiana. BOI can interact and ubiquitinate L5 in vitro, and mediate the proteasomal degradation of L5 in N. benthamiana and Arabidopsis. The Lys425 in the NBS domain of L5 is the critical unbiquitin site for the degradation. In conclusion, our results reveal a mechanism for the control of the stability of L5 protein and for the suppressed of L5-triggered cell death by a RING-type E3 ligase through the ubiquitin proteasome system.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas NLR/metabolismo , Nicotiana/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Arabidopsis/inmunología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/inmunología , Proteínas NLR/genética , Proteínas NLR/inmunología , Inmunidad de la Planta , Complejo de la Endopetidasa Proteasomal/inmunología , Dominios Proteicos , Nicotiana/inmunología , Ubiquitina-Proteína Ligasas/inmunología
12.
J Immunol Res ; 2021: 9975628, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34239945

RESUMEN

Age-related macular degeneration (AMD), a degenerative disease of the outer retina, is the leading cause of blindness among the elderly. A hallmark of geographic atrophy (GA), an advanced type of nonneovascular AMD (dry AMD), is photoreceptor and retinal pigment epithelium (RPE) cell death. Currently, there are no FDA-approved therapies for GA due to a lack of understanding of the disease-causing mechanisms. Increasing evidence suggests that chronic inflammation plays a predominant role in the pathogenesis of dry AMD. Dead or stressed cells release danger signals and inflammatory factors, which causes further damage to neighboring cells. It has been reported that type I interferon (IFN) response is activated in RPE cells in patients with AMD. However, how RPE cells sense stress to initiate IFN response and cause further damage to the retina are still unknown. Although it has been reported that RPE can respond to extracellularly added dsRNA, it is unknown whether and how RPE detects and senses internally generated or internalized nucleic acids. Here, we elucidated the molecular mechanism by which RPE cells sense intracellular nucleic acids. Our data demonstrate that RPE cells can respond to intracellular RNA and induce type I IFN responses via the RIG-I (DExD/H-box helicase 58, DDX58) RNA helicase. In contrast, we showed that RPE cells were unable to directly sense and respond to DNA through the cGAS-STING pathway. We demonstrated that this was due to the absence of the cyclic GMP-AMP synthase (cGAS) DNA sensor in these cells. The activation of IFN response via RIG-I induced expression of cell death effectors and caused barrier function loss in RPE cells. These data suggested that RPE-intrinsic pathways of nucleic acid sensing are biased toward RNA sensing.


Asunto(s)
Proteína 58 DEAD Box/metabolismo , Degeneración Macular/inmunología , ARN Bicatenario/metabolismo , Receptores Inmunológicos/metabolismo , Epitelio Pigmentado de la Retina/patología , Apoptosis/inmunología , Línea Celular , Proteína 58 DEAD Box/genética , Técnicas de Inactivación de Genes , Humanos , Interferón Tipo I/metabolismo , Degeneración Macular/patología , Estrés Oxidativo , Receptores Inmunológicos/genética , Epitelio Pigmentado de la Retina/inmunología , Epitelio Pigmentado de la Retina/metabolismo
13.
ChemistryOpen ; 10(7): 666-671, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33829677

RESUMEN

During the last decades, there has been growing interest in using therapeutic messager RNA (mRNA) together with drug delivery systems. Naked, unformulated mRNA is, however, unable to cross the cell membrane and is susceptible to degradation. Here we use graphene quantum dots (GQDs) functionalized with polyethyleneimine (PEI) as a novel mRNA delivery system. Our results show that these modified GQDs can be used to deliver intact and functional mRNA to Huh-7 hepatocarcinoma cells at low doses and, that the GQDs are not toxic, although cellular toxicity is a problem for these first-generation modified particles. Functionalized GQDs represent a potentially interesting delivery system that is easy to manufacture, stable and effective.


Asunto(s)
Colorantes Fluorescentes/química , Grafito/química , Polietileneimina/química , Puntos Cuánticos/química , ARN Mensajero/química , Línea Celular Tumoral , Permeabilidad de la Membrana Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Imagen Óptica , Puntos Cuánticos/metabolismo , ARN Mensajero/metabolismo , Transfección
14.
Methods Mol Biol ; 2263: 423-446, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33877611

RESUMEN

A wide range of biological processes rely on complexes between ribonucleic acids (RNAs) and proteins. Determining the three-dimensional structures of RNA-protein complexes is crucial to elucidate the relationship between structure and biological function. X-ray crystallography represents the most widely used technique to characterize RNA-protein complexes at atomic resolution; however, determining their three-dimensional structures remains challenging. RNase contamination can ruin crystallization experiments by degrading RNA in complex with protein, leading to sample heterogeneity, and the conformational flexibility inherent in both protein and RNA can limit crystallizability. Furthermore, the three-dimensional structure can be difficult to accurately model at the typical diffraction limit of 2.5 Å resolution or lower for RNA-protein complex crystals. At this resolution, phosphates, which are electron dense, and bases, which are large, rigid, and planar, tend to be well resolved and easy to position in the electron density map, whereas other features, e.g., sugar atoms, can be difficult to accurately position. This chapter focuses on methods that can be used to overcome the unique problems faced when crystallizing RNA-protein complexes and determining their three-dimensional structures using X-ray crystallography.


Asunto(s)
Proteínas/química , Proteínas/metabolismo , ARN/química , ARN/metabolismo , Sitios de Unión , Biología Computacional , Cristalografía por Rayos X , Ensayo de Cambio de Movilidad Electroforética , Modelos Moleculares , Conformación Proteica , Dominios Proteicos , Pliegue del ARN
15.
Biochem Biophys Res Commun ; 555: 40-45, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-33812057

RESUMEN

RIN4 is an important immunomodulator in Arabidopsis, which is targeted by multiple pathogenic effectors, and consequently guarded by different immune receptors. Although RIN4 plays a significant role in plant immunity, its molecular function is not fully understood. We found that RIN4 interacts with the exocyst subunit EXO70E2. Transiently expressed RIN4 can recruits EXO70E2 vesicles to the plasma membrane, and promote the transport of the vesicles to the extracellular matrix. RIN4 also can decrease the protein level of EXO70E2. Base on the fact that EXO70 proteins positively mediates plant immunity, the function of RIN4 is to promote the extracellular export of defense related vesicles. Pathogens will secret effectors to modify or cleavage it to interfere this exocytosis.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Arabidopsis/citología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Membrana Celular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Inmunidad de la Planta , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente , Transporte de Proteínas , Nicotiana/genética , Proteínas de Transporte Vesicular/genética
16.
Front Immunol ; 12: 602330, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33717084

RESUMEN

Wnt signaling is one of the fundamental pathways that play a major role in almost every aspect of biological systems. In addition to the well-known influence of Wnt signaling on bone formation, its essential role in the immune system also attracted increasing attention. Sclerostin, a confirmed Wnt antagonist, is also proven to modulate the development and differentiation of normal immune cells, particularly B cells. Aptamers, single-stranded (ss) oligonucleotides, are capable of specifically binding to a variety of target molecules by virtue of their unique three-dimensional structures. With in-depth study of those functional nucleic acids, they have been gradually applied to diagnostic and therapeutic area in immune diseases due to their various advantages over antibodies. In this review, we focus on several issues including the roles of Wnt signaling and Wnt antagonist sclerostin in the immune system. For the sake of understanding, current examples of aptamers applications for the immune diseases are also discussed. At the end of this review, we propose our ideas for the future research directions.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Aptámeros de Nucleótidos , Sistema Inmunológico/inmunología , Sistema Inmunológico/metabolismo , Inmunidad , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Humanos , Inmunomodulación , Investigación , Técnica SELEX de Producción de Aptámeros , Transducción de Señal , Linfocitos T/inmunología , Linfocitos T/metabolismo , Vía de Señalización Wnt
17.
Biochem Biophys Res Commun ; 534: 206-211, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33272575

RESUMEN

Nucleotide-binding site (NBS) and leucine-rich repeat (LRR) receptors (NLRs) play important roles in plant immunity. The genome of Arabidopsis thaliana contains about 150 genes encoding NLR proteins, but few of them have been studied. We transiently expressed a series of NBS-LRR proteins in the leaves of Nicotiana benthamiana, and found that the CC-NBS-LRR protein (AT1G12290) was able to trigger cell death, a characterized function for the activation of an NLR protein. We observed that the YFP-tagged AT1G12290 was localized on the plasma membrane (PM), and the predicted myristoylation site Gly2 is required for the localization and function of the protein. Further structure dissection revealed that the CC domain was enough to activate cell death, and the N-terminal 1-100 amino acid fragment was the minimal region to induce cell death and self-association. Our research provides important clues to elucidate the activation mechanism of AT1G12290.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Proteínas NLR/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Muerte Celular , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas NLR/química , Proteínas NLR/genética , Dominios Proteicos , Nicotiana/genética
18.
ACS Appl Mater Interfaces ; 13(8): 9500-9519, 2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-32603135

RESUMEN

Aptamers are oligonucleotide sequences with a length of about 25-80 bases which have abilities to bind to specific target molecules that rival those of monoclonal antibodies. They are attracting great attention in diverse clinical translations on account of their various advantages, including prolonged storage life, little batch-to-batch differences, very low immunogenicity, and feasibility of chemical modifications for enhancing stability, prolonging the half-life in serum, and targeted delivery. In this Review, we demonstrate the emerging aptamer discovery technologies in developing advanced techniques for producing aptamers with high performance consistently and efficiently as well as requiring less cost and resources but offering a great chance of success. Further, the diverse modifications of aptamers for therapeutic applications including therapeutic agents, aptamer-drug conjugates, and targeted delivery materials are comprehensively summarized.


Asunto(s)
Aptámeros de Nucleótidos/uso terapéutico , Portadores de Fármacos/química , Animales , Aptámeros de Nucleótidos/química , Ensayos Analíticos de Alto Rendimiento/instrumentación , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Dispositivos Laboratorio en un Chip , Liposomas/química , Nanopartículas del Metal/química , Péptidos/química , Técnica SELEX de Producción de Aptámeros/instrumentación , Técnica SELEX de Producción de Aptámeros/métodos
19.
Front Cell Dev Biol ; 8: 576110, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33015068

RESUMEN

Since calcium and phosphorus play vital roles in a multitude of physiologic systems, disorders of calcium and phosphorus metabolism always lead to severe consequences such as skeletal-related and cardiovascular morbidity, or even life-threatening. Physiologically, the maintenance of calcium and phosphorus homeostasis is achieved via a variety of concerted actions of hormones such as parathyroid hormone (PTH), vitamin D, and fibroblast growth factor (FGF23), which could be regulated mainly at three organs, the intestine, kidney, and bone. Disruption of any organ or factor might lead to disorders of calcium and phosphorus metabolism. Currently, lacking of accurate diagnostic approaches and unknown molecular basis of pathophysiology will result in patients being unable to receive a precise diagnosis and personalized treatment timely. Therefore, it is urgent to identify early diagnostic biomarkers and develop therapeutic strategies. Fortunately, proteomics and metabolomics offer promising tools to discover novel indicators and further understanding of pathological mechanisms. Therefore, in this review, we will give a systematic introduction on PTH-1,25(OH)2D-FGF23 axis in the disorders of calcium and phosphorus metabolism, diagnostic biomarkers identified, and potential altered metabolic pathways involved.

20.
Med Sci Monit ; 26: e925583, 2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32574155

RESUMEN

BACKGROUND The clinical challenges of triple-negative breast cancer (TNBC) includes the lack of targeted therapy and chemoresistance. TNBC has relatively high PD-L1 expression, and PD-L1 antibody in combination with nab-paclitaxel has been approved by FDA for TNBC treatment. Aptamers, also termed chemical antibody, are widely used in targeted drug delivery. The present study aimed to select a DNA aptamer that could specifically bind and deliver drugs to TNBC cells. MATERIAL AND METHODS An innovative loss-gain cell-SELEX strategy was used to select DNA aptamer for PD-L1 protein. Construction of PD-L1 knock-out and over-expression MDA-MB-231 cell lines were conducted through transfection and confirmed by western blot and flow cytometry. Confocal microscopy and flow cytometry were used to analyze the binding ability of aptamer with TNBC cells. The cytotoxicity of aptamer-paclitaxel complex against TNBC cells was evaluated by Cell Counting Kit-8 assay. The reactivation of the T cell function by aptamer was measured by IL-2 enzyme-linked immunosorbent assay after T cells co-cultured with tumor cells. RESULTS In this work, using an innovative loss-gain cell-SELEX strategy, we screened a PD-L1-targeting aptamer. PD-L1 aptamer selectively bound to PD-L1 over-expressed TNBC cells with a dissociation constant in the nanomolar range. PD-L1 aptamer could also inhibit PD-1/PD-L1 interaction and restore the function of T cells. Moreover, we developed a PD-L1 aptamer-paclitaxel conjugate which showed improved cellular uptake and anti-proliferation efficacy in PD-L1 over-expressed TNBC cells. CONCLUSIONS In summary, these findings suggest that the selected PD-L1 aptamer might have potential implication in immune modulation and targeted therapy against TNBC.


Asunto(s)
Aptámeros de Péptidos/farmacología , Antígeno B7-H1/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Anticuerpos/uso terapéutico , Antígeno B7-H1/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Femenino , Humanos , Paclitaxel/farmacología , Receptor de Muerte Celular Programada 1/metabolismo , Técnica SELEX de Producción de Aptámeros/métodos
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