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1.
Plant Cell ; 34(11): 4600-4622, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-35929080

RESUMEN

Hemicellulose polysaccharides influence assembly and properties of the plant primary cell wall (PCW), perhaps by interacting with cellulose to affect the deposition and bundling of cellulose fibrils. However, the functional differences between plant cell wall hemicelluloses such as glucomannan, xylan, and xyloglucan (XyG) remain unclear. As the most abundant hemicellulose, XyG is considered important in eudicot PCWs, but plants devoid of XyG show relatively mild phenotypes. We report here that a patterned ß-galactoglucomannan (ß-GGM) is widespread in eudicot PCWs and shows remarkable similarities to XyG. The sugar linkages forming the backbone and side chains of ß-GGM are analogous to those that make up XyG, and moreover, these linkages are formed by glycosyltransferases from the same CAZy families. Solid-state nuclear magnetic resonance indicated that ß-GGM shows low mobility in the cell wall, consistent with interaction with cellulose. Although Arabidopsis ß-GGM synthesis mutants show no obvious growth defects, genetic crosses between ß-GGM and XyG mutants produce exacerbated phenotypes compared with XyG mutants. These findings demonstrate a related role of these two similar but distinct classes of hemicelluloses in PCWs. This work opens avenues to study the roles of ß-GGM and XyG in PCWs.


Asunto(s)
Arabidopsis , Xilanos , Arabidopsis/genética , Pared Celular/química , Celulosa
2.
J Biomed Sci ; 30(1): 96, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110940

RESUMEN

BACKGROUND: Human enteroviruses A71 (EV-A71) and D68 (EV-D68) are the suspected causative agents of hand-foot-and-mouth disease, aseptic meningitis, encephalitis, acute flaccid myelitis, and acute flaccid paralysis in children. Until now, no cure nor mucosal vaccine existed for EV-A71 and EV-D68. Novel mucosal bivalent vaccines are highly important for preventing EV-A71 and EV-D68 infections. METHODS: In this study, formalin-inactivated EV-A71 and EV-D68 were used as antigens, while PS-G, a polysaccharide from Ganoderma lucidum, was used as an adjuvant. Natural polysaccharides have the characteristics of intrinsic immunomodulation, biocompatibility, low toxicity, and safety. Mice were immunized intranasally with PBS, EV-A71, EV-D68, or EV-A71 + EV-D68, with or without PS-G as an adjuvant. RESULTS: The EV-A71 + EV-D68 bivalent vaccine generated considerable EV-A71- and EV-D68-specific IgG and IgA titres in the sera, nasal washes, saliva, bronchoalveolar lavage fluid, and feces. These antibodies neutralized EV-D68 and EV-A71 infectivity. They also cross-neutralized infections by different EV-D68 and EV-A71 sub-genotypes. Furthermore, compared with the PBS group, EV-A71 + EV-D68 + PS-G-vaccinated mice exhibited an increased number of EV-D68- and EV-A71-specific IgA- and IgG-producing cells. In addition, T-cell proliferative responses, and IFN-γ and IL-17 secretion in the spleen were substantially induced when PS-G was used as an adjuvant with EV-A71 + EV-D68. Finally, in vivo challenge experiments demonstrated that the immune sera induced by EV-A71 + EV-D68 + PS-G conferred protection in neonate mice against lethal EV-A71 and EV-D68 challenges as indicated by the increased survival rate and decreased clinical score and viral RNA tissue expression. Taken together, all EV-A71/EV-D68 + PS-G-immunized mice developed potent specific humoral, mucosal, and cellular immune responses to EV-D68 and EV-A71 and were protected against them. CONCLUSIONS: These findings demonstrated that PS-G can be used as a potential adjuvant for EV-A71 and EV-D68 bivalent mucosal vaccines. Our results provide useful information for the further preclinical and clinical development of a mucosal bivalent enterovirus vaccine against both EV-A71 and EV-D68 infections.


Asunto(s)
Enterovirus Humano A , Enterovirus Humano D , Infecciones por Enterovirus , Enterovirus , Reishi , Niño , Animales , Humanos , Ratones , Enterovirus Humano D/genética , Enterovirus Humano A/genética , Vacunas Combinadas , Antígenos Virales , Inmunoglobulina A , Inmunoglobulina G
3.
Acta Pharmacol Sin ; 44(10): 1962-1976, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37169852

RESUMEN

Atherosclerosis is a major cause of death and disability in cardiovascular disease. Atherosclerosis associated with lipid accumulation and chronic inflammation leads to plaques formation in arterial walls and luminal stenosis in carotid arteries. Current approaches such as surgery or treatment with statins encounter big challenges in curing atherosclerosis plaque. The infiltration of proinflammatory M1 macrophages plays an essential role in the occurrence and development of atherosclerosis plaque. A recent study shows that TRIM24, an E3 ubiquitin ligase of a Trim family protein, acts as a valve to inhibit the polarization of anti-inflammatory M2 macrophages, and elimination of TRIM24 opens an avenue to achieve the M2 polarization. Proteolysis-targeting chimera (PROTAC) technology has emerged as a novel tool for the selective degradation of targeting proteins. But the low bioavailability and cell specificity of PROTAC reagents hinder their applications in treating atherosclerosis plaque. In this study we constructed a type of bioinspired PROTAC by coating the PROTAC degrader (dTRIM24)-loaded PLGA nanoparticles with M2 macrophage membrane (MELT) for atherosclerosis treatment. MELT was characterized by morphology, size, and stability. MELT displayed enhanced specificity to M1 macrophages as well as acidic-responsive release of dTRIM24. After intravenous administration, MELT showed significantly improved accumulation in atherosclerotic plaque of high fat and high cholesterol diet-fed atherosclerotic (ApoE-/-) mice through binding to M1 macrophages and inducing effective and precise TRIM24 degradation, thus resulting in the polarization of M2 macrophages, which led to great reduction of plaque formation. These results suggest that MELT can be considered a potential therapeutic agent for targeting atherosclerotic plaque and alleviating atherosclerosis progression, providing an effective strategy for targeted atherosclerosis therapy.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Quimera Dirigida a la Proteólisis , Animales , Ratones , Antiinflamatorios/uso terapéutico , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Inflamación/tratamiento farmacológico , Macrófagos , Ratones Endogámicos C57BL , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/metabolismo , Quimera Dirigida a la Proteólisis/farmacología , Quimera Dirigida a la Proteólisis/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Nanopartículas/uso terapéutico
4.
J Xray Sci Technol ; 31(6): 1315-1332, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37840464

RESUMEN

BACKGROUND: Dental panoramic imaging plays a pivotal role in dentistry for diagnosis and treatment planning. However, correctly positioning patients can be challenging for technicians due to the complexity of the imaging equipment and variations in patient anatomy, leading to positioning errors. These errors can compromise image quality and potentially result in misdiagnoses. OBJECTIVE: This research aims to develop and validate a deep learning model capable of accurately and efficiently identifying multiple positioning errors in dental panoramic imaging. METHODS AND MATERIALS: This retrospective study used 552 panoramic images selected from a hospital Picture Archiving and Communication System (PACS). We defined six types of errors (E1-E6) namely, (1) slumped position, (2) chin tipped low, (3) open lip, (4) head turned to one side, (5) head tilted to one side, and (6) tongue against the palate. First, six Convolutional Neural Network (CNN) models were employed to extract image features, which were then fused using transfer learning. Next, a Support Vector Machine (SVM) was applied to create a classifier for multiple positioning errors, using the fused image features. Finally, the classifier performance was evaluated using 3 indices of precision, recall rate, and accuracy. RESULTS: Experimental results show that the fusion of image features with six binary SVM classifiers yielded high accuracy, recall rates, and precision. Specifically, the classifier achieved an accuracy of 0.832 for identifying multiple positioning errors. CONCLUSIONS: This study demonstrates that six SVM classifiers effectively identify multiple positioning errors in dental panoramic imaging. The fusion of extracted image features and the employment of SVM classifiers improve diagnostic precision, suggesting potential enhancements in dental imaging efficiency and diagnostic accuracy. Future research should consider larger datasets and explore real-time clinical application.


Asunto(s)
Aprendizaje Profundo , Sistemas de Información Radiológica , Humanos , Estudios Retrospectivos , Diagnóstico por Imagen , Redes Neurales de la Computación
5.
J Cell Mol Med ; 26(11): 3153-3168, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35322540

RESUMEN

Autologous adipose tissue is an ideal soft tissue filling material, and its biocompatibility is better than that of artificial tissue substitutes, foreign bodies and heterogeneous materials. Although autologous fat transplantation has many advantages, the low retention rate of adipose tissue limits its clinical application. Here, we identified a secretory glycoprotein, leucine-rich-alpha-2-glycoprotein 1 (LRG-1), that could promote fat graft survival through RAB31-mediated inhibition of hypoxia-induced apoptosis. We showed that LRG-1 injection significantly increased the maintenance of fat volume and weight compared with the control. In addition, higher fat integrity, more viable adipocytes and fewer apoptotic cells were observed in the LRG-1-treated groups. Furthermore, we discovered that LRG-1 could reduce the ADSC apoptosis induced by hypoxic conditions. The mechanism underlying the LRG-1-mediated suppression of the ADSC apoptosis induced by hypoxia was mediated by the upregulation of RAB31 expression. Using LRG-1 for fat grafts may prove to be clinically successful for increasing the retention rate of transplanted fat.


Asunto(s)
Tejido Adiposo , Apoptosis , Materiales Biocompatibles , Glicoproteínas , Supervivencia de Injerto , Proteínas de Unión al GTP rab , Tejido Adiposo/trasplante , Apoptosis/efectos de los fármacos , Glicoproteínas/administración & dosificación , Glicoproteínas/farmacología , Supervivencia de Injerto/efectos de los fármacos , Supervivencia de Injerto/fisiología , Humanos , Hipoxia/patología , Inyecciones Subcutáneas , Trasplante Autólogo , Proteínas de Unión al GTP rab/metabolismo
6.
Anal Chem ; 94(11): 4643-4649, 2022 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-35258931

RESUMEN

Hyaluronidase (HAase) is implicated in inflammation, cancer development, and allergic reaction. The detection of HAase is significantly important in clinical diagnosis and medical treatment. Herein, we propose a new principle for the development of equipment-free and label-free paper-based flow sensors based on the enzymatic hydrolysis-induced viscosity change in a stimuli-responsive polymer solution, which increases the water flow distance on the pH indicator paper. The detection of HAase is demonstrated as an example. This facile and versatile method can overcome the potential drawbacks of traditional hydrogel-based sensors, including complex preparation steps, slow response time, or low sensitivity. Moreover, it can also avoid the use of specialized instruments, labeled molecules, or functionalized nanoparticles in the sensors developed using the polymer solutions. Using this strategy, the detection of HAase is achieved with a limit of detection as low as 0.2 U/mL. Also, it works well in human urine. Additionally, the detection of tannic acid, which is an inhibitor of HAase, is also fulfilled. Overall, a simple, efficient, high-throughput, and low-cost detection method is developed for the rapid and quantitative detection of HAase and its inhibitor without the use of labeled molecules, synthetic particles, and specialized instruments. As only minimal reagents of HAase, HA, and paper are used, it is very promising in the development of commercial kits for point-of-care testing.


Asunto(s)
Hialuronoglucosaminidasa , Polímeros , Humanos , Ácido Hialurónico/química , Hialuronoglucosaminidasa/orina , Hidrólisis , Viscosidad
7.
J Hum Genet ; 67(5): 273-278, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34983973

RESUMEN

Methadone is a synthetic opioid used for the maintenance treatment (MMT) of heroin dependence. It primarily binds to the µ-opioid receptor (MOR; with its gene, namely OPRM1). Methadone is also an N-methyl-D-aspartate (NMDA) receptor antagonist. The role of NMDA receptor in the regulatory mechanisms of methadone dosage in heroin dependent patients is so far not clear. D-amino acid oxidase (DAO) is an important enzyme that indirectly activates the NMDA receptor through its effect on the D-serine level. To test the hypothesis that genetic polymorphisms in the DAO gene are associated with methadone treatment dose and responses, we selected four single nucleotide polymorphisms (SNPs) in DAO from the literature reports of the Taiwanese population. SNPs were genotyped in 344 MMT patients. In this study, we identified a functional SNP rs55944529 in the DAO gene that reveals a modest but significant association with the methadone dosage in the recessive model of analysis (P = 0.003) and plasma concentrations (P = 0.003) in MMT patients. However, it did not show association with plasma methadone concentration in multiple linear regression analysis. It is also associated with the methadone adverse reactions of dry mouth (P = 0.002), difficulty with urination (P = 0.0003) in the dominant model, and the withdrawal symptoms of yawning (P = 0.005) and gooseflesh skin (P = 0.004) in the recessive model. Our results suggest a role of the indirect regulatory mechanisms of the NMDA reporter, possibly via the DAO genetic variants, in the methadone dose and some adverse reactions in MMT patients.


Asunto(s)
Heroína , Metadona , Humanos , Metadona/efectos adversos , N-Metilaspartato/genética , Oxidorreductasas/genética , Polimorfismo de Nucleótido Simple , Receptores de N-Metil-D-Aspartato/genética
8.
Ecotoxicol Environ Saf ; 241: 113764, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35709673

RESUMEN

Numerous studies have documented that excessive fluoride intake could cause pathological damage and functional disorder in organisms. Nevertheless, the systemic mechanism of fluorosis inhibiting the proliferation and development of splenic cell is still scarce. The preliminary studies have confirmed that high-dose NaF could inhibit splenic lymphocytes proliferation in vitro and cause toxic effects on spleen development in vivo. Here this study continued to explore the signaling pathway with the methods of quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB), revealing the mechanism of fluorosis in the growth system. Mice in 4 groups (control, 12 mg/kg, 24 mg/kg, 48 mg/kg) were gavage administrated with NaF solution continuously for 42 days. The results suggested that NaF more than 12 mg/kg slowed down the growth of mice, inhibited spleen growth and development, which was characterized by decreasing spleen volume, and inducing splenic cell apoptosis. For the Ras-Raf-MEK-ERK signaling pathway, the mRNA and protein expression levels of Ras were significantly elevated, and the phosphorylated protein expression levels of Raf (B-Raf, C-Raf) were increased. Meanwhile, mice mRNA expression levels were increased in a time and dose-dependent manner on the 21st and 42nd days of the experiment. Additionally, the mRNA and protein levels of MEK1/2 were increased on the 21st day of the experiment, while reduced on the 42nd day. The ERK1/2 levels were significantly decreased at both 21st and 42nd days of the experiment. This study showed that NaF activated Ras to induce downstream Raf-MEK-ERK cascade reaction, but failed to activate ERK eventually, the proliferation signal from the cell surface could not transmit to the nucleus, interfering with the regulation of cell proliferation, differentiation, meiosis, and suppressed spleen development ultimately.


Asunto(s)
Sistema de Señalización de MAP Quinasas , Fluoruro de Sodio , Animales , Ratones , Quinasas de Proteína Quinasa Activadas por Mitógenos , ARN Mensajero , Transducción de Señal , Fluoruro de Sodio/toxicidad , Bazo
9.
J Virol ; 94(17)2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32581104

RESUMEN

Cap-independent translation initiation on picornavirus mRNAs is mediated by an internal ribosomal entry site (IRES) in the 5' untranslated region. The regulation of internal initiation requires the interaction of IRES-transacting factors (ITAFs) with the IRES. In this study, we identified a novel ITAF, heterogeneous nuclear ribonucleoprotein K (hnRNP K), which negatively regulates foot-and-mouth disease virus (FMDV) translation and viral replication. Further investigation revealed that the KH2 and KH3 domains of hnRNP K directly bind to domains II, III, and IV of the FMDV IRES, resulting in the inhibition of IRES-mediated translation by interfering with the recognition of another positive ITAF, polypyrimidine tract-binding protein (PTB). Conversely, hnRNP K-mediated inhibition was antagonized by the viral 3C protease through the cleavage of hnRNP K at the Glu-364 residue during FMDV infection. Interestingly, the N-terminal cleavage product, hnRNP K1-364, retained partial inhibitory effects on IRES activity, whereas the C-terminal cleavage product, hnRNP K364-465, became a positive regulator of FMDV replication. Our findings expand the current understanding of virus-host interactions concerning viral recruitment and the modulation of ITAFs, providing new insights into translational control during viral infection.IMPORTANCE The translation of picornaviral genome RNA mediated by the internal ribosomal entry site (IRES) is a crucial step for virus infections. Virus-host interactions play a critical role in the regulation of IRES-dependent translation, but the regulatory mechanism remains largely unknown. In this study, we identified an ITAF, hnRNP K, that negatively regulates FMDV replication by inhibiting viral IRES-mediated translation. In addition, we describe a novel translational regulation mechanism involving the proteolytic cleavage of hnRNP K by FMDV protease 3C. The cleavage of hnRNP K yields two cleavage products with opposite functions: the cleavage product hnRNP K1-364 retains a partial inhibitory effect on IRES activity, and the cleavage product hnRNP K364-465 becomes a positive regulator of FMDV replication. Our findings shed light on the effect of a novel ITAF on the translational regulation of picornavirus and provide new insights into translational control during viral infection.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Virus de la Fiebre Aftosa/fisiología , Ribonucleoproteína Heterogénea-Nuclear Grupo K/metabolismo , Sitios Internos de Entrada al Ribosoma/fisiología , Transactivadores/metabolismo , Proteínas Virales/metabolismo , Replicación Viral/fisiología , Proteasas Virales 3C , Animales , Línea Celular , Cricetinae , Virus de la Fiebre Aftosa/genética , Regulación Viral de la Expresión Génica , Células HEK293 , Humanos , Proteína de Unión al Tracto de Polipirimidina , ARN Mensajero , Proteínas Virales/genética
10.
J Virol ; 95(1)2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33028719

RESUMEN

The low fidelity of foot-and-mouth disease virus (FMDV) RNA-dependent RNA polymerase allows FMDV to exhibit high genetic diversity. Previously, we showed that the genetic diversity of FMDV plays an important role in virulence in suckling mice. Here, we mutated the amino acid residue Phe257, located in the finger domain of FMDV polymerase and conserved across FMDV serotypes, to a cysteine (F257C) to study the relationship between viral genetic diversity, virulence, and transmissibility in natural hosts. The single amino acid substitution in FMDV polymerase resulted in a high-fidelity virus variant, rF257C, with growth kinetics indistinguishable from those of wild-type (WT) virus in cell culture, but it displayed smaller plaques and impaired fitness in direct competition assays. Furthermore, we found that rF257C was attenuated in vivo in both suckling mice and pigs (one of its natural hosts). Importantly, contact exposure experiments showed that the rF257C virus exhibited reduced transmissibility compared to that of wild-type FMDV in the porcine model. This study provides evidence that FMDV genetic diversity is important for viral virulence and transmissibility in susceptible animals. Given that type O FMDV exhibits the highest genetic diversity among all seven serotypes of FMDV, we propose that the lower polymerase fidelity of the type O FMDV could contribute to its dominance worldwide.IMPORTANCE Among the seven serotypes of FMDV, serotype O FMDV have the broadest distribution worldwide, which could be due to their high virulence and transmissibility induced by high genetic diversity. In this paper, we generated a single amino acid substitution FMDV variant with a high-fidelity polymerase associated with viral fitness, virulence, and transmissibility in a natural host. The results highlight that maintenance of viral population diversity is essential for interhost viral spread. This study provides evidence that higher genetic diversity of type O FMDV could increase both virulence and transmissibility, thus leading to their dominance in the global epidemic.


Asunto(s)
Virus de la Fiebre Aftosa/patogenicidad , Fiebre Aftosa/virología , ARN Polimerasa Dependiente del ARN/fisiología , Proteínas no Estructurales Virales/fisiología , Animales , Línea Celular , Cricetinae , Virus de la Fiebre Aftosa/enzimología , Virus de la Fiebre Aftosa/genética , Aptitud Genética , Variación Genética , Ratones , Mutación , Fenotipo , ARN Polimerasa Dependiente del ARN/genética , Porcinos , Proteínas no Estructurales Virales/genética , Virulencia
11.
J Virol ; 94(10)2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32161169

RESUMEN

Upon infection, the highly structured 5' untranslated region (5' UTR) of picornavirus is involved in viral protein translation and RNA synthesis. As a critical element in the 5' UTR, the internal ribosome entry site (IRES) binds to various cellular proteins to function in the processes of picornavirus replication. Foot-and-mouth disease virus (FMDV) is an important member in the family Picornaviridae, and its 5' UTR contains a functional IRES element. In this study, the cellular heterogeneous nuclear ribonucleoprotein L (hnRNP L) was identified as an IRES-binding protein for FMDV by biotinylated RNA pulldown assays, mass spectrometry (MS) analysis, and determination of hnRNP L-IRES interaction regions. Further, we found that hnRNP L inhibited the growth of FMDV through binding to the viral IRES and that the inhibitory effect of hnRNP L on FMDV growth was not due to FMDV IRES-mediated translation, but to influence on viral RNA synthesis. Finally, hnRNP L was demonstrated to coimmunoprecipitate with RNA-dependent RNA polymerase (3Dpol) in an FMDV RNA-dependent manner in the infected cells. Thus, our results suggest that hnRNP L, as a critical IRES-binding protein, negatively regulates FMDV replication by inhibiting viral RNA synthesis, possibly by remaining in the replication complex.IMPORTANCE Picornaviruses, as a large family of human and animal pathogens, cause a bewildering array of disease syndromes. Many host factors are implicated in the pathogenesis of these viruses, and some proteins interact with the viral IRES elements to affect function. Here, we report for the first time that cellular hnRNP L specifically interacts with the IRES of the picornavirus FMDV and negatively regulates FMDV replication through inhibiting viral RNA synthesis. Further, our results showed that hnRNP L coimmunoprecipitates with FMDV 3Dpol in a viral RNA-dependent manner, suggesting that it may remain in the replication complex to function. The data presented here would facilitate further understanding of virus-host interactions and the pathogenesis of picornavirus infections.


Asunto(s)
Regiones no Traducidas 5' , Virus de la Fiebre Aftosa/fisiología , Ribonucleoproteína Heterogénea-Nuclear Grupo L/metabolismo , Sitios Internos de Entrada al Ribosoma/fisiología , ARN Viral/biosíntesis , Replicación Viral/fisiología , Animales , Línea Celular , Virus de la Fiebre Aftosa/genética , Regulación Viral de la Expresión Génica , Técnicas de Inactivación de Genes , Células HEK293 , Ribonucleoproteína Heterogénea-Nuclear Grupo L/genética , Interacciones Microbiota-Huesped/fisiología , Humanos , Inmunoprecipitación , Unión Proteica , ARN Viral/genética , Transcriptoma
12.
J Virol ; 94(16)2020 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-32493820

RESUMEN

Foot-and-mouth disease (FMD), which is caused by FMD virus (FMDV), remains a major plague among cloven-hoofed animals worldwide, and its outbreak often has disastrous socioeconomic consequences. A live-attenuated FMDV vaccine will greatly facilitate the global control and eradication of FMD, but a safe and effective attenuated FMDV vaccine has not yet been successfully developed. Here, we found that the internal ribosome entry site (IRES) element in the viral genome is a critical virulence determinant of FMDV, and a nucleotide substitution of cytosine (C) for guanine (G) at position 351 of the IRES endows FMDV with temperature-sensitive and attenuation (ts&att) phenotypes. Furthermore, we demonstrated that the C351G mutation of IRES causes a temperature-dependent translation defect by impairing its binding to cellular pyrimidine tract-binding protein (PTB), resulting in the ts&att phenotypes of FMDV. Natural hosts inoculated with viruses carrying the IRES C351G mutation showed no clinical signs, viremia, virus excretion, or viral transmission but still produced a potent neutralizing antibody response that provided complete protection. Importantly, the IRES C351G mutation is a universal determinant of the ts&att phenotypes of different FMDV strains, and the C351G mutant was incapable of reversion to virulence during in vitro and in vivo passages. Collectively, our findings suggested that manipulation of the IRES, especially its C351G mutation, may serve as a feasible strategy to develop live-attenuated FMDV vaccines.IMPORTANCE The World Organization for Animal Health has called for global control and eradication of foot-and-mouth disease (FMD), the most economically and socially devastating disease affecting animal husbandry worldwide. Live-attenuated vaccines are considered the most effective strategy for prevention, control, and eradication of infectious diseases due to their capacity to induce potent and long-lasting protective immunity. However, efforts to develop FMD virus (FMDV) live-attenuated vaccines have achieved only limited success. Here, by structure-function study of the FMDV internal ribosome entry site (IRES), we find that the C351 mutation of the IRES confers FMDV with an ideal temperature-sensitive attenuation phenotype by decreasing its interaction with cellular pyrimidine tract-binding protein (PTB) to cause IRES-mediated temperature-dependent translation defects. The temperature-sensitive attenuated strains generated by manipulation of the IRES address the challenges of FMDV attenuation differences among various livestock species and immunogenicity maintenance encountered previously, and this strategy can be applied to other viruses with an IRES to rationally design and develop live-attenuated vaccines.


Asunto(s)
Virus de la Fiebre Aftosa/genética , Sitios Internos de Entrada al Ribosoma/genética , Animales , Anticuerpos Neutralizantes/metabolismo , Bovinos , Femenino , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/metabolismo , Virus de la Fiebre Aftosa/patogenicidad , Regulación Viral de la Expresión Génica/genética , Sitios Internos de Entrada al Ribosoma/fisiología , Masculino , Ratones , Ratones Endogámicos BALB C , Mutación/genética , Ribosomas/genética , Porcinos , Vacunas Atenuadas , Virulencia/genética , Replicación Viral/genética
13.
Strahlenther Onkol ; 197(12): 1131-1142, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34476531

RESUMEN

PURPOSE: Development of a safe and effective systemic chemotherapeutic agent for concurrent administration with definitive thoracic radiotherapy remains a major goal of lung cancer management. The synergistic effect of PEGylated liposomal doxorubicin and irradiation was evaluated in lung cancer cell lines both in vitro and in vivo. METHODS: In vitro radiosensitization of A549 and LLC cell lines was evaluated by colony formation assay, γH2AX fluorescent staining and western blot assay, and annexin V staining. A radiosensitization study with healthy human lung-derived cell line BEAS-2B was performed for comparative purposes. In vivo radiosensitization was evaluated by tumor ectopic growth, cell survival, pharmacokinetics, and biodistribution analyses. Cleaved caspase­3, the marker for apoptosis, was assessed immunohistochemically in A549 xenograft tumors. RESULTS: Treatment with PEGylated liposomal doxorubicin decreased A549 and LLC cell proliferation in a dose-dependent manner. In vitro studies revealed comparable radiosensitizer advantages of PEGylated liposomal doxorubicin and free doxorubicin, showing equivalent DNA double-strand breaks according to γH2AX fluorescent staining and western blot assays, similar numbers of apoptotic cells in the annexin­V staining assay, and moderately decreased clonogenic survival. In vivo studies demonstrated markedly slow ectopic tumor growth with prolonged survival following treatment with PEGylated liposomal doxorubicin plus irradiation in both A549 and LLC mouse models, suggesting that PEGylated liposomal doxorubicin is more effective as a radiosensitizer than free doxorubicin in vivo. Pharmacokinetics evaluation showed a longer half-life of approximately 40 h for PEGylated liposomal doxorubicin, confirming that the liposomal carrier achieved controlled release. Biodistribution evaluation of PEGylated liposomal doxorubicin confirmed high accumulation of doxorubicin in tumors, indicating the promising drug delivery attributes of PEGylated liposomal doxorubicin. Although free doxorubicin caused histopathologic myocarditis with the cardiac muscle fibers showing varying degrees of damage, PEGylated liposomal doxorubicin caused no such effects. The immunohistochemical expression of cleaved caspase-3-positive cells was greatest expressed in the irradiation and PEGylated liposomal doxorubicin combined treatment group, indicating prolonged tumoricidal effects. CONCLUSIONS: Our study provides preclinical in vitro and in vivo evidence of the effectiveness of PEGylated liposomal doxorubicin as a radiosensitizer, supporting its potential clinical development as a component of chemoradiotherapy.


Asunto(s)
Doxorrubicina , Neoplasias Pulmonares , Animales , Quimioradioterapia , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacología , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Polietilenglicoles , Distribución Tisular
14.
BMC Oral Health ; 21(1): 229, 2021 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-33941169

RESUMEN

BACKGROUND: The relationship between dental caries and periodontal disease is still controversial. The objective of this study was to explore the relationship between different types of caries and periodontal disease severity in middle-aged and elderly people in China. METHODS: The study population consisted of 4407 middle-aged and 4117 elderly subjects. Caries were divided into the following three types: type A, crown caries; type B, lesions involving both the crown and root, representing mixed-type caries; and type C, root caries. These three types together represent the overall caries situation, which we call type ABC. Caries were quantitated by decayed and filled teeth (DFT index). Periodontitis was evaluated by clinical attachment loss. RESULTS: Middle-aged people with periodontitis had a significant association with DFT type B (OR: 1.21, 95% CI 1.17-1.25) and type C (OR: 1.40, 95% CI 1.24-1.56). Elderly people with periodontitis had a significant association with DFT type C (OR: 1.28, 95% CI 1.21-1.35). CONCLUSIONS: In China, caries types B/C were positively correlated with periodontitis in the middle-aged group, and only caries type C was positively correlated with periodontitis in the elderly group.


Asunto(s)
Caries Dental , Enfermedades Periodontales , Anciano , China/epidemiología , Índice CPO , Caries Dental/epidemiología , Susceptibilidad a Caries Dentarias , Encuestas de Salud Bucal , Humanos , Persona de Mediana Edad , Salud Bucal , Enfermedades Periodontales/complicaciones , Enfermedades Periodontales/epidemiología
15.
Int J Dent Hyg ; 19(4): 398-406, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33768685

RESUMEN

OBJECTIVE: To investigate the effect of a new powered toothbrush with tapered bristles on the brush head for the reduction of dental plaque and gingivitis. METHODS: This was a single-centre, single-group, longitudinal clinical trial. Thirty-two participants who were typical manual toothbrush users were recruited and assigned the sonic-powered brush. Interviews were arranged on the 1st , 4th , and 15th days which represented the baseline (T1 ), middle (T2 ) and final (T3 ) time points, respectively. At each visit, the plaque index (PlI), gingival index (GI), bleeding on probing (BOP) and probing depth (PD) were recorded for the Ramfjord index teeth, gingival crevicular fluid(GCF) samples were collected and the proportions of eight periodontal pathogenic bacteria were analysed. Repeated-measures analysis of variance (ANOVA) was used for comparisons at different time points. RESULTS: PlI was significantly reduced by 41.67% from T1 to T2 (p<0.001) and decreased by 18.57% from T2 to T3 (p=0.003). GI also varied significantly from T1 to T2 (p=0.018) and T1 to T3 (p=0.037). A 35.86% reduction in the BOP percentage occurred after using the sonic-powered toothbrush for 3 days (p=0.001). However, no significant difference was observed in the mean values of PD at different examination intervals (p=0.529). There was no significant difference in the proportions of bacteria between T1 and T3 (p>0.05). CONCLUSION: This research demonstrated the efficacy of the sonic-powered brush handle together with tapered bristles on the brush in reducing plaque and gingivitis within a short time period.


Asunto(s)
Placa Dental , Gingivitis , Placa Dental/prevención & control , Índice de Placa Dental , Diseño de Equipo , Gingivitis/prevención & control , Humanos , Índice Periodontal , Método Simple Ciego , Cepillado Dental
16.
J Gen Virol ; 100(2): 187-198, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30547855

RESUMEN

In this study, ten sites on the N terminus and different surface variable regions (VRs) of the bovine parvovirus (BPV) VP2 capsid protein were selected according to an alignment of its sequence with that of the BPV-1 strain HADEN for insertion of the type O foot-and-mouth disease virus (FMDV) conserved neutralizing epitope 8E8. Ten epitope-chimeric BPV VP2 capsid proteins carrying the 8E8 epitope were expressed in Sf9 cells, and electron micrographs demonstrated that these fusion proteins self-assembled into virus-like particles (VLPs) with properties similar to those of natural BPV virions. Immunofluorescence assay (IFA) and Western blot analysis demonstrated that each of the ten epitope-chimeric VLPs reacted with both anti-BPV serum and anti-type O FMDV mAb 8E8. These results indicated that insertions of the 8E8 epitope at these sites on the BPV VP2 protein did not interfere with the immunoreactivity of VP2 or VLP formation, and that the exogenous epitope 8E8 was correctly expressed in BPV VLPs. In addition, anti-BPV IgG antibodies were induced in mice by intramuscular inoculation with each of the ten chimeric VLPs, indicating that the immunogenicity of the chimeric VLPs was not disrupted. Importantly, potent anti-FMDV viral neutralizing (VN) antibodies, which exhibited the highest titre of 1 : 176, were induced by two chimeric VLPs, rBPV-VLP-8E8(391) and rBPV-VLP-8E8(395), in which the 8E8 epitope was inserted into positions 391/392 and 395/396, respectively, in the VR VIII of BPV VP2. Our results demonstrated that the 391/392 and 395/396 positions in the VR VIII of the BPV VP2 protein can effectively display a foreign epitope, making this an attractive approach for the design of nanoparticle-vectored and epitope-based vaccines.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Bocavirus/genética , Epítopos/inmunología , Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Vacunas de Partículas Similares a Virus/inmunología , Animales , Proteínas de la Cápside/genética , Portadores de Fármacos , Epítopos/genética , Virus de la Fiebre Aftosa/genética , Inmunoglobulina G/sangre , Inyecciones Intramusculares , Ratones , Células Sf9 , Spodoptera , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Vacunas de Partículas Similares a Virus/administración & dosificación , Vacunas de Partículas Similares a Virus/genética
17.
Small ; 15(49): e1903296, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31709707

RESUMEN

Irinotecan is one of the main chemotherapeutic agents for colorectal cancer (CRC). MicroRNA-200 (miR-200) has been reported to inhibit metastasis in cancer cells. Herein, pH-sensitive and peptide-modified liposomes and solid lipid nanoparticles (SLN) are designed for encapsulation of irinotecan and miR-200, respectively. These peptides include one cell-penetrating peptide, one ligand targeted to tumor neovasculature undergoing angiogenesis, and one mitochondria-targeting peptide. The peptide-modified nanoparticles are further coated with a pH-sensitive PEG-lipid derivative with an imine bond. These specially-designed nanoparticles exhibit pH-responsive release, internalization, and intracellular distribution in acidic pH of colon cancer HCT116 cells. These nanoparticles display low toxicity to blood and noncancerous intestinal cells. Delivery of miR-200 by SLN further increases the cytotoxicity of irinotecan-loaded liposomes against CRC cells by triggering apoptosis and suppressing RAS/ß-catenin/ZEB/multiple drug resistance (MDR) pathways. Using CRC-bearing mice, the in vivo results further indicate that irinotecan and miR-200 in pH-responsive targeting nanoparticles exhibit positive therapeutic outcomes by inhibiting colorectal tumor growth and reducing systemic toxicity. Overall, successful delivery of miR and chemotherapy by multifunctional nanoparticles may modulate ß-catenin/MDR/apoptosis/metastasis signaling pathways and induce programmed cancer cell death. Thus, these pH-responsive targeting nanoparticles may provide a potential regimen for effective treatment of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Irinotecán/uso terapéutico , MicroARNs/administración & dosificación , MicroARNs/uso terapéutico , Nanopartículas/química , Animales , Apoptosis/fisiología , Neoplasias Colorrectales/tratamiento farmacológico , Endocitosis/fisiología , Células HCT116 , Humanos , Concentración de Iones de Hidrógeno , Etiquetado Corte-Fin in Situ , Irinotecán/administración & dosificación , Masculino , Ratones , Ratones Endogámicos BALB C , Polietilenglicoles/química , Tomografía Computarizada por Tomografía de Emisión de Positrones
18.
Plant Physiol ; 178(3): 1011-1026, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30185440

RESUMEN

The interaction between mannan polysaccharides and cellulose microfibrils contributes to cell wall properties in some vascular plants, but the molecular arrangement of mannan in the cell wall and the nature of the molecular bonding between mannan and cellulose remain unknown. Previous studies have shown that mannan is important in maintaining Arabidopsis (Arabidopsis thaliana) seed mucilage architecture, and that Cellulose Synthase-Like A2 (CSLA2) synthesizes a glucomannan backbone, which Mannan α-Galactosyl Transferase1 (MAGT1/GlycosylTransferase-Like6/Mucilage Related10) might decorate with single α-Gal branches. Here, we investigated the ratio and sequence of Man and Glc and the arrangement of Gal residues in Arabidopsis mucilage mannan using enzyme sequential digestion, carbohydrate gel electrophoresis, and mass spectrometry. We found that seed mucilage galactoglucomannan has a backbone consisting of the repeating disaccharide [4)-ß-Glc-(1,4)-ß-Man-(1,], and most of the Man residues in the backbone are substituted by single α-1,6-Gal. CSLA2 is responsible for the synthesis of this patterned glucomannan backbone and MAGT1 catalyses the addition of α-Gal. In vitro activity assays revealed that MAGT1 transferred α-Gal from UDP-Gal only to Man residues within the CSLA2 patterned glucomannan backbone acceptor. These results indicate that CSLAs and galactosyltransferases are able to make precisely defined galactoglucomannan structures. Molecular dynamics simulations suggested this patterned galactoglucomannan is able to bind stably to some hydrophilic faces and to hydrophobic faces of cellulose microfibrils. A specialization of the biosynthetic machinery to make galactoglucomannan with a patterned structure may therefore regulate the mode of binding of this hemicellulose to cellulose fibrils.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Celulosa/metabolismo , Galactosiltransferasas/metabolismo , Glucosiltransferasas/metabolismo , Glicosiltransferasas/metabolismo , Mananos/química , Arabidopsis/química , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Pared Celular/metabolismo , Galactosiltransferasas/genética , Glucosiltransferasas/genética , Glicosiltransferasas/genética , Mananos/metabolismo , Mucílago de Planta/química , Mucílago de Planta/metabolismo , Polisacáridos/metabolismo , Semillas/química , Semillas/enzimología , Semillas/genética
19.
Biomacromolecules ; 20(7): 2809-2820, 2019 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-31185717

RESUMEN

Transient increase of reactive oxygen species (ROS) is vital for some physiological processes, whereas the chronic and sustained high ROS level is usually implicated in the inflammatory diseases and cancers. Herein, we report the innovative redox-responsive theranostic micellar nanoparticles that are able to load anticancer drugs through coordination and hydrophobic interaction and to fluorescently monitor the intracellular redox status. The nanoparticles were formed by the amphiphilic block copolymers composed of a PEG segment and a selenide-containing hydrophobic polycarbonate block with a small fraction of coumarin-based chromophore. Under the alternative redox stimulation that might be encountered in the physiological process of some healthy cells, these nanoparticles underwent the reversible changes in size, morphology, and fluorescence intensity. With the assistance of small model compounds, we clarified the chemistry behind these changes, that is, the redox triggered reversible transformation between selenide and selenoxide. Upon the monotonic oxidation similar to the sustained high ROS level of cancer cells, the nanoparticles could be disrupted completely, which was accompanied by the drastic decrease in fluorescence. Cisplatin and paclitaxel were simultaneously coloaded in the nanoparticles with a moderate efficacy, and the coordination between selenide and platinum improved the stability of the drug-loaded nanoparticles against dilution. The naked nanoparticles are cytocompatible, whereas the dual drug-loaded nanoparticles exhibited a concentration dependent and synergistic cytotoxicity to triple-negative breast cancer (TNBC) cells. Of importance, the drug-loaded nanoparticles are much more toxic to TNBC cells than to normal cells due in part to ROS overproduction in the former cell lines.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Liberación de Fármacos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Micelas , Oxidación-Reducción , Paclitaxel/química , Paclitaxel/farmacología , Cemento de Policarboxilato/química , Cemento de Policarboxilato/farmacología , Especies Reactivas de Oxígeno/química , Neoplasias de la Mama Triple Negativas/patología
20.
J Nanobiotechnology ; 17(1): 89, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31426807

RESUMEN

BACKGROUND: The emergence of resistance to chemotherapy or target therapy, tumor metastasis, and systemic toxicity caused by available anticancer drugs hamper the successful colorectal cancer (CRC) treatment. The rise in epidermal growth factor receptor (EGFR; human epidermal growth factor receptor 1; HER1) expression and enhanced phosphorylation of HER2 and HER3 are associated with tumor resistance, metastasis and invasion, thus resulting in poor outcome of anti-CRC therapy. The use of afatinib, a pan-HER inhibitor, is a potential therapeutic approach for resistant CRC. Additionally, miR-139 has been reported to be negatively correlated with chemoresistance, metastasis, and epithelial-mesenchymal transition (EMT) of CRC. Hence, we develop a nanoparticle formulation consisting of a polymer core to carry afatinib or miR-139, which is surrounded by lipids modified with a targeting ligand and a pH-sensitive penetrating peptide to improve the anticancer effect of cargos against CRC cells. RESULTS: Our findings show that this formulation displays a spherical shape with core/shell structure, homogeneous particle size distribution and negative zeta potential. The prepared formulations demonstrate a pH-sensitive release profile and an enhanced uptake of cargos into human colorectal adenocarcinoma Caco-2 cells in response to the acidic pH. This nanoparticle formulation incorporating afatinib and miR-139 exhibits low toxicity to normal cells but shows a better inhibitory effect on Caco-2 cells than other formulations. Moreover, the encapsulation of afatinib and miR-139 in peptide-modified nanoparticles remarkably induces apoptosis and inhibits migration and resistance of Caco-2 cells via suppression of pan-HER tyrosine kinase/multidrug resistance/metastasis pathways. CONCLUSION: This study proposes a multifunctional nanoparticle formulation for targeted modulation of apoptosis/EGFR/HER/EMT/resistance/progression pathways to increase the sensitivity of colon cancer cells to afatinib.


Asunto(s)
Afatinib/química , Antineoplásicos/química , Lípidos/química , MicroARNs/química , Nanopartículas/química , Péptidos/química , Polímeros/química , Afatinib/farmacología , Afatinib/uso terapéutico , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Células CACO-2 , Línea Celular Tumoral , Química Farmacéutica/métodos , Neoplasias Colorrectales/tratamiento farmacológico , Resistencia a Antineoplásicos/efectos de los fármacos , Receptores ErbB/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Péptidos/farmacología , Péptidos/uso terapéutico , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Ratas , Ratas Sprague-Dawley
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