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1.
Mol Ther ; 32(2): 411-425, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38098229

RESUMEN

Radiotherapy (RT), administered to roughly half of all cancer patients, occupies a crucial role in the landscape of cancer treatment. However, expanding the clinical indications of RT remains challenging. Inspired by the radiation-induced bystander effect (RIBE), we used the mediators of RIBE to mimic RT. Specifically, we discovered that irradiated tumor cell-released microparticles (RT-MPs) mediated the RIBE and had immune activation effects. To further boost the immune activation effect of RT-MPs to achieve cancer remission, even in advanced stages, we engineered RT-MPs with different cytokine and chemokine combinations by modifying their production method. After comparing the therapeutic effect of the engineered RT-MPs in vitro and in vivo, we demonstrated that tIL-15/tCCL19-RT-MPs effectively activated antitumor immune responses, significantly prolonged the survival of mice with malignant pleural effusion (MPE), and even achieved complete cancer remission. When tIL-15/tCCL19-RT-MPs were combined with PD-1 monoclonal antibody (mAb), a cure rate of up to 60% was achieved. This combination therapy relied on the activation of CD8+ T cells and macrophages, resulting in the inhibition of tumor growth and the establishment of immunological memory against tumor cells. Hence, our research may provide an alternative and promising strategy for cancers that are not amenable to conventional RT.


Asunto(s)
Micropartículas Derivadas de Células , Derrame Pleural Maligno , Humanos , Animales , Ratones , Linfocitos T CD8-positivos , Terapia Combinada , Citocinas , Microambiente Tumoral , Línea Celular Tumoral
2.
Cardiovasc Diabetol ; 23(1): 192, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844974

RESUMEN

BACKGROUND: Cardiovascular disease (CVD) is closely associated with the triglyceride glucose (TyG) index and its related indicators, particularly its combination with obesity indices. However, there is limited research on the relationship between changes in TyG-related indices and CVD, as most studies have focused on baseline TyG-related indices. METHODS: The data for this prospective cohort study were obtained from the China Health and Retirement Longitudinal Study. The exposures were changes in TyG-related indices and cumulative TyG-related indices from 2012 to 2015. The K-means algorithm was used to classify changes in each TyG-related index into four classes (Class 1 to Class 4). Multivariate logistic regressions were used to evaluate the associations between the changes in TyG-related indices and the incidence of CVD. RESULTS: In total, 3243 participants were included in this study, of whom 1761 (54.4%) were female, with a mean age of 57.62 years at baseline. Over a 5-year follow-up, 637 (19.6%) participants developed CVD. Fully adjusted logistic regression analyses revealed significant positive associations between changes in TyG-related indices, cumulative TyG-related indices and the incidence of CVD. Among these changes in TyG-related indices, changes in TyG-waist circumference (WC) showed the strongest association with incident CVD. Compared to the participants in Class 1 of changes in TyG-WC, the odds ratio (OR) for participants in Class 2 was 1.41 (95% confidence interval (CI) 1.08-1.84), the OR for participants in Class 3 was 1.54 (95% CI 1.15-2.07), and the OR for participants in Class 4 was 1.94 (95% CI 1.34-2.80). Moreover, cumulative TyG-WC exhibited the strongest association with incident CVD among cumulative TyG-related indices. Compared to the participants in Quartile 1 of cumulative TyG-WC, the OR for participants in Quartile 2 was 1.33 (95% CI 1.00-1.76), the OR for participants in Quartile 3 was 1.46 (95% CI 1.09-1.96), and the OR for participants in Quartile 4 was 1.79 (95% CI 1.30-2.47). CONCLUSIONS: Changes in TyG-related indices are independently associated with the risk of CVD. Changes in TyG-WC are expected to become more effective indicators for identifying individuals at a heightened risk of CVD.


Asunto(s)
Biomarcadores , Glucemia , Enfermedades Cardiovasculares , Obesidad , Triglicéridos , Humanos , Femenino , Persona de Mediana Edad , Masculino , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/sangre , Estudios Prospectivos , Triglicéridos/sangre , Incidencia , Medición de Riesgo , China/epidemiología , Glucemia/metabolismo , Obesidad/epidemiología , Obesidad/diagnóstico , Obesidad/sangre , Anciano , Biomarcadores/sangre , Estudios Longitudinales , Factores de Tiempo , Pronóstico , Factores de Riesgo de Enfermedad Cardiaca , Valor Predictivo de las Pruebas , Factores de Riesgo
3.
Brain Behav Immun ; 115: 543-554, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37989443

RESUMEN

Autoimmunity plays a key role in the pathogenesis of Alzheimer's disease (AD). However, whether autoantibodies in peripheral blood can be used as biomarkers for AD has been elusive. Serum samples were obtained from 1,686 participants, including 767 with AD, 146 with mild cognitive impairment (MCI), 255 with other neurodegenerative diseases, and 518 healthy controls. Specific autoantibodies were measured using a custom-made immunoassay. Multivariate support vector machine models were employed to investigate the correlation between serum autoantibody levels and disease states. As a result, seven candidate AD-specific autoantibodies were identified, including MAPT, DNAJC8, KDM4D, SERF1A, CDKN1A, AGER, and ASXL1. A classification model with high accuracy (area under the curve (AUC) = 0.94) was established. Importantly, these autoantibodies could distinguish AD from other neurodegenerative diseases and out-performed amyloid and tau protein concentrations in cerebrospinal fluid in predicting cognitive decline (P < 0.001). This study indicated that AD onset and progression are possibly accompanied by an unappreciated serum autoantibody response. Therefore, future studies could optimize its application as a convenient biomarker for the early detection of AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico , Proteínas tau/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores , Disfunción Cognitiva/diagnóstico , Autoanticuerpos , Progresión de la Enfermedad , Fragmentos de Péptidos/líquido cefalorraquídeo , Histona Demetilasas con Dominio de Jumonji , Proteínas del Tejido Nervioso
4.
J Nanobiotechnology ; 22(1): 170, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38610012

RESUMEN

Neurodegenerative diseases (NDDs) such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis epitomize a class of insidious and relentless neurological conditions that are difficult to cure. Conventional therapeutic regimens often fail due to the late onset of symptoms, which occurs well after irreversible neurodegeneration has begun. The integrity of the blood-brain barrier (BBB) further impedes efficacious drug delivery to the central nervous system, presenting a formidable challenge in the pharmacological treatment of NDDs. Recent scientific inquiries have shifted focus toward the peripheral biological systems, investigating their influence on central neuropathology through the lens of extracellular vesicles (EVs). These vesicles, distinguished by their ability to breach the BBB, are emerging as dual operatives in the context of NDDs, both as conveyors of pathogenic entities and as prospective vectors for therapeutic agents. This review critically summarizes the burgeoning evidence on the role of extracerebral EVs, particularly those originating from bone, adipose tissue, and gut microbiota, in modulating brain pathophysiology. It underscores the duplicity potential of peripheral EVs as modulators of disease progression and suggests their potential as novel vehicles for targeted therapeutic delivery, positing a transformative impact on the future landscape of NDD treatment strategies. Search strategy A comprehensive literature search was conducted using PubMed, Web of Science, and Scopus from January 2000 to December 2023. The search combined the following terms using Boolean operators: "neurodegenerative disease" OR "Alzheimer's disease" OR "Parkinson's disease" OR "Amyotrophic lateral sclerosis" AND "extracellular vesicles" OR "exosomes" OR "outer membrane vesicles" AND "drug delivery systems" AND "blood-brain barrier". MeSH terms were employed when searching PubMed to refine the results. Studies were included if they were published in English, involved human subjects, and focused on the peripheral origins of EVs, specifically from bone, adipose tissue, and gut microbiota, and their association with related diseases such as osteoporosis, metabolic syndrome, and gut dysbiosis. Articles were excluded if they did not address the role of EVs in the context of NDDs or did not discuss therapeutic applications. The titles and abstracts of retrieved articles were screened using a dual-review process to ensure relevance and accuracy. The reference lists of selected articles were also examined to identify additional relevant studies.


Asunto(s)
Enfermedad de Alzheimer , Exosomas , Vesículas Extracelulares , Enfermedad de Parkinson , Humanos , Estudios Prospectivos
5.
Artículo en Inglés | MEDLINE | ID: mdl-38401085

RESUMEN

Background: Herpes Zoster Neuralgia (HZN) and Post-Herpetic Neuralgia (PHN) are neuropathic pain conditions following Varicella Zoster Virus infection. PHN primarily affects individuals aged 60 and above and the pervasive and severe neuropathic pain in PHN leads to significant emotional and psychological distress in approximately 80%-90% of patients, precipitating a decline in their overall quality of life and that of their families. Galectin-3, a pro-inflammatory factor, is implicated in inflammatory responses, potentially influencing neuronal damage and pain signal transmission. Objective: This study aims to evaluate the clinical relevance of serum Galectin-3 in HZN and PHN patients, alongside other contributing factors. Methods: We retrospectively analyzed data collected from 40 HZN patients, 40 non-HZN patients, and 20 healthy controls in our hospital between 2015 and 2017. Variables included demographic data, clinical characteristics, and inflammatory markers. Statistical analyses comprised t-tests, ANOVA, chi-square tests, and multivariate logistic regression. A Receiver Operating Characteristic (ROC) curve was constructed to evaluate Galectin-3's predictive value for PHN. Results: PHN patients showed significantly higher ages, NRS scores, and prevalence of shingles in the head and neck region compared to Non-PHN and Non-HZN groups (P < .05). Elevated levels of IL-6 (66.33±8.93 pg/mL) and Galectin-3 (2.44±0.29 ng/mL) were observed in HZN patients. Galectin-3 emerged as a significant risk factor for PHN development (P < .05), while other factors such as age, shingles location, IL-6, and T lymphocyte subsets did not show a significant impact. Conclusion: Galectin-3 may serve as a predictive biomarker for PHN development, offering insights into its pathophysiology and potential therapeutic targets. Patients with elevated Galectin-3 levels might benefit from specific targeted therapies or interventions aimed at reducing Galectin-3 levels and mitigating its effects.

6.
Plant Physiol ; 188(1): 460-476, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-34730827

RESUMEN

Lateral branches such as shoot and panicle are determining factors and target traits for rice (Oryza sativa L.) yield improvement. Cytokinin promotes rice lateral branching; however, the mechanism underlying the fine-tuning of cytokinin homeostasis in rice branching remains largely unknown. Here, we report the map-based cloning of RICE LATERAL BRANCH (RLB) encoding a nuclear-localized, KNOX-type homeobox protein from a rice cytokinin-deficient mutant showing more tillers, sparser panicles, defected floret morphology as well as attenuated shoot regeneration from callus. RLB directly binds to the promoter and represses the transcription of OsCKX4, a cytokinin oxidase gene with high abundance in panicle branch meristem. OsCKX4 over-expression lines phenocopied rlb, which showed upregulated OsCKX4 levels. Meanwhile, RLB physically binds to Polycomb repressive complex 2 (PRC2) components OsEMF2b and co-localized with H3K27me3, a suppressing histone modification mediated by PRC2, in the OsCKX4 promoter. We proposed that RLB recruits PRC2 to the OsCKX4 promoter to epigenetically repress its transcription, which suppresses the catabolism of cytokinin, thereby promoting rice lateral branching. Moreover, antisense inhibition of OsCKX4 under the LOG promoter successfully increased panicle size and spikelet number per plant without affecting other major agronomic traits. This study provides insight into cytokinin homeostasis, lateral branching in plants, and also promising target genes for rice genetic improvement.


Asunto(s)
Meristema/genética , Meristema/metabolismo , Oryza/crecimiento & desarrollo , Oryza/genética , Oryza/metabolismo , Reguladores del Crecimiento de las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo , Metilación/efectos de los fármacos , Plantas Modificadas Genéticamente
7.
J Neurol Neurosurg Psychiatry ; 94(6): 436-447, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36650038

RESUMEN

BACKGROUND: The pathogenic missense mutations of the gelsolin (GSN) gene lead to familial amyloidosis of the Finnish type (FAF); however, our previous study identified GSN frameshift mutations existed in patients with Alzheimer's disease (AD). The GSN genotype-phenotype heterogeneity and the role of GSN frameshift mutations in patients with AD are unclear. METHOD: In total, 1192 patients with AD and 1403 controls were screened through whole genome sequencing, and 884 patients with AD were enrolled for validation. Effects of GSN mutations were evaluated in vitro. GSN, Aß42, Aß40 and Aß42/40 were detected in both plasma and cerebrospinal fluid (CSF). RESULTS: Six patients with AD with GSN P3fs and K346fs mutations (0.50%, 6/1192) were identified, who were diagnosed with AD but not FAF. In addition, 13 patients with AD with GSN frameshift mutations were found in the validation cohort (1.47%, 13/884). Further in vitro experiments showed that both K346fs and P3fs mutations led to the GSN loss of function in inhibiting Aß-induced toxicity. Moreover, a higher level of plasma (p=0.001) and CSF (p=0.005) GSN was observed in AD cases than controls, and a positive correlation was found between the CSF GSN and CSF Aß42 (r=0.289, p=0.009). Besides, the GSN level was initially increasing and then decreasing with the disease course and cognitive decline. CONCLUSIONS: GSN frameshift mutations may be associated with AD. An increase in plasma GSN is probably a compensatory reaction in AD, which is a potential biomarker for early AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/líquido cefalorraquídeo , Mutación del Sistema de Lectura , Disfunción Cognitiva/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Fragmentos de Péptidos/líquido cefalorraquídeo
8.
Int J Mol Sci ; 24(13)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37446259

RESUMEN

Chilling stress seriously limits grain yield and quality worldwide. However, the genes and the underlying mechanisms that respond to chilling stress remain elusive. This study identified ABF1, a cold-induced transcription factor of the bZIP family. Disruption of ABF1 impaired chilling tolerance with increased ion leakage and reduced proline contents, while ABF1 over-expression lines exhibited the opposite tendency, suggesting that ABF1 positively regulated chilling tolerance in rice. Moreover, SnRK2 protein kinase SAPK10 could phosphorylate ABF1, and strengthen the DNA-binding ability of ABF1 to the G-box cis-element of the promoter of TPS2, a positive regulator of trehalose biosynthesis, consequently elevating the TPS2 transcription and the endogenous trehalose contents. Meanwhile, applying exogenous trehalose enhanced the chilling tolerance of abf1 mutant lines. In summary, this study provides a novel pathway 'SAPK10-ABF1-TPS2' involved in rice chilling tolerance through regulating trehalose homeostasis.


Asunto(s)
Oryza , Oryza/metabolismo , Trehalosa/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Quinasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Frío , Proteínas de Plantas/metabolismo
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(12): 1287-1292, 2023 Dec 15.
Artículo en Zh | MEDLINE | ID: mdl-38112149

RESUMEN

Immunoglobulin A vasculitis (IgAV), also known as Henoch-Schönlein purpura, has complex etiology and pathogenesis which have not been fully clarified. The latest research shows that SARS-CoV-2 and related vaccines, human papilloma vaccine, and certain biological agents can also induce IgAV. Most studies believe that the formation of galactose-deficient IgA1 (Gd-IgA1) and Gd-IgA1-containing immune complex plays a crucial role in the pathogenesis of IgAV. It is hypothesized that the pathogenesis of IgAV is associated with the binding of IgA1 to anti-endothelial cell antibodies. In addition, genetics also constitutes a major focus of IgAV research. This article reviews the new advances in the etiology of IgAV and summarizes the role of Gd-IgA1, Gd-IgA1-containing immune complex, anti-endothelial antibody, IgA1 conjugates, T lymphocyte immunity, and genetic factors in the pathogenesis of IgAV.


Asunto(s)
Vasculitis por IgA , Humanos , Complejo Antígeno-Anticuerpo , Inmunoglobulina A/genética
10.
Neurobiol Dis ; 172: 105819, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35842134

RESUMEN

BACKGROUND: Genetics plays an important role in progressive supranuclear palsy (PSP) and remains poorly understood. A detailed literature search identified 19 PSP-associated genes: MAPT, LRRK2, LRP10, DCTN1, GRN, NPC1, PARK, TARDBP, TBK1, BSN, GBA, STX6, EIF2AK3, MOBP, DUSP10, SLCO1A2, RUNX2, CXCR4, and APOE. To date, genetic studies on PSP have focused on Caucasian population. The gaps in PSP genetic study on East Asian populations need to be filled. METHODS: Exon and flanking regions of the PSP-associated genes were sequenced in 104 patients with PSP and 488 healthy controls. Common variant-based association analysis and gene-based association tests of rare variants were performed using PLINK 1.9 and the sequence kernel association test-optimal, respectively. Additionally, the association of APOE and MAPT genotypes with PSP was evaluated. The above association analyses were repeated among probable PSP patients. Finally, PLINK 1.9 was used to test variants associated with the onset age of PSP. RESULTS: A rare non-pathogenic variant of MAPT (c.425C > T,p.A142V) was detected in a PSP patient. No common variants were significantly associated with PSP. In both the rare-variant and the rare-damaging-variant groups, the combined effect for GBA reached statistical significance (p = 1.43 × 10-3, p = 4.98 × 10-4). The result between APOE, MAPT genotypes and PSP risk were inconsistent across all PSP group and probably PSP group. CONCLUSIONS: The pathogenic variant in MAPT were uncommon in PSP patients. Moreover, GBA gene was likely to increase the risk of PSP, and GBA-associated diseases were beyond α-synucleinopathies. The association between APOE, MAPT and PSP is still unclear among the non-Caucasian population.


Asunto(s)
Parálisis Supranuclear Progresiva , Apolipoproteínas E , Pueblo Asiatico/genética , China , Fosfatasas de Especificidad Dual , Humanos , Fosfatasas de la Proteína Quinasa Activada por Mitógenos , Parálisis Supranuclear Progresiva/genética , Parálisis Supranuclear Progresiva/patología , Proteínas tau/genética
11.
Plant Physiol ; 182(4): 2047-2064, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32029522

RESUMEN

Plant male gametogenesis is a coordinated effort involving both reproductive tissues and sporophytic tissues, in which lipid metabolism plays an essential role. Although GDSL esterases/lipases have been well known as key enzymes for many plant developmental processes and stress responses, their functions in reproductive development remain unclear. Here, we report the identification of a rice male sterile2 (rms2) mutant in rice (Oryza sativa), which is completely male sterile due to the defects in tapetum degradation, cuticle formation in sporophytic tissues, and impaired exine and central vacuole development in pollen grains. RMS2 was map-based cloned as an endoplasmic reticulum-localized GDSL lipase gene, which is predominantly transcribed during early anther development. In rms2, a three-nucleotide deletion and one base substitution (TTGT to A) occurred within the GDSL domain, which reduced the lipid hydrolase activity of the resulting protein and led to significant changes in the content of 16 lipid components and numerous other metabolites, as revealed by a comparative metabolic analysis. Furthermore, RMS2 is directly targeted by the male fertility regulators Undeveloped Tapetum1 and Persistent Tapetal Cell1 both in vitro and in vivo, suggesting that RMS2 may serve as a key node in the rice male fertility regulatory network. These findings shed light on the function of GDSLs in reproductive development and provide a promising gene resource for hybrid rice breeding.


Asunto(s)
Lipasa/metabolismo , Oryza/metabolismo , Oryza/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Lipasa/genética , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reproducción/genética , Reproducción/fisiología
12.
Int J Mol Sci ; 22(22)2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34830102

RESUMEN

Gibberellins (GAs) are diterpenoid phytohormones regulating various aspects of plant growth and development, such as internode elongation and seed germination. Although the GA biosynthesis pathways have been identified, the transcriptional regulatory network of GA homeostasis still remains elusive. Here, we report the functional characterization of a GA-inducible OsABF1 in GA biosynthesis underpinning plant height and seed germination. Overexpression of OsABF1 produced a typical GA-deficient phenotype with semi-dwarf and retarded seed germination. Meanwhile, the phenotypes could be rescued by exogenous GA3, suggesting that OsABF1 is a key regulator of GA homeostasis. OsABF1 could directly suppress the transcription of green revolution gene SD1, thus reducing the endogenous GA level in rice. Moreover, OsABF1 interacts with and transcriptionally antagonizes to the polycomb repression complex component OsEMF2b, whose mutant showed as similar but more severe phenotype to OsABF1 overexpression lines. It is suggested that OsABF1 recruits RRC2-mediated H3K27me3 deposition on the SD1 promoter, thus epigenetically silencing SD1 to maintain the GA homeostasis for growth and seed germination. These findings shed new insight into the functions of OsABF1 and regulatory mechanism underlying GA homeostasis in rice.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación , Giberelinas/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Semillas/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Oryza/genética , Proteínas de Plantas/genética , Semillas/genética
13.
Eur J Neurosci ; 52(8): 4009-4017, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32506655

RESUMEN

Recently, functional studies have demonstrated that legumain (LGMN) cleaves both amyloid ß-protein precursor and tau, promoting senile plaques and formation of neurofibrillary tangles, which may play a crucial role in the pathogenesis of Alzheimer's disease (AD). However, the genetic role of LGMN in AD has not been clearly elucidated. Here, we used Sanger sequencing to investigate the single independent (single-variant association test) and cumulative (gene-based association test) effects of variants in the LGMN gene as potential susceptibility factors for AD, in a cohort comprising 676 AD cases and 365 elderly controls from the Han population of South China. In single-variant association analysis, none of the common variants in LGMN were statistically significant. In gene-based analysis, the LGMN gene also showed no association with AD. The results of our replication study in the Alzheimer's Disease Neuroimaging Initiative cohort also showed no association between LGMN and AD. These findings suggest that the LGMN gene may not be a critical factor for AD development.


Asunto(s)
Enfermedad de Alzheimer , Anciano , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides , China , Cisteína Endopeptidasas , Humanos , Polimorfismo de Nucleótido Simple
15.
Mar Drugs ; 18(6)2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32486103

RESUMEN

: Mild acid hydrolysis is a common method for the structure analysis of fucosylated glycosaminoglycan (FG). In this work, the effects of acid hydrolysis on the structure of FG from S. variegatus (SvFG) and the reaction characteristic were systemically studied. The degree of defucosylation (DF) and molecular weights (Mw) of partial fucosylated glycosaminoglycans (pFs) were monitored by 1H NMR and size-exclusion chromatography, respectively. The kinetic plots of DF, degree of desulfation (DS) from fucose branches, and degree of hydrolysis (DH) of the backbone are exponentially increased with time, indicating that acid hydrolysis of SvFG followed a first-order kinetics. The kinetic rate constants kDF, kDS, and kDH were determined to be 0.0223 h-1, 0.0041 h-1, and 0.0005 h-1, respectively. The structure of the released sulfated fucose branches (FucS) from SvFG and HfFG (FG from H. fuscopunctata) was characterized by 1D/2D NMR spectroscopy, suggesting the presence of six types of fucose: α/ß Fuc2S4S, Fuc3S4S, Fuc3S, Fuc4S, Fuc2S, and Fuc. The Fuc3S4S was more susceptible to acid than Fuc2S4S, and that the sulfate ester in position of O-2 and O-3 than in O-4 of fucose. The structure characteristic of pF18 indicated the cleavage of backbone glycosidic bonds. The APTT prolonged activity reduced with the decrease of the DF and Mw of the pFs, and became insignificant when its DF was 87% with Mw of 3.5 kDa.


Asunto(s)
Fucosa/química , Glicosaminoglicanos/química , Oligosacáridos/química , Pepinos de Mar/química , Animales , Humanos , Hidrólisis , Espectroscopía de Resonancia Magnética , Relación Estructura-Actividad
16.
Mar Drugs ; 17(4)2019 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-30934713

RESUMEN

Apostichopus japonicus is one of the most economically important species in sea cucumber aquaculture in China. Fucosylated glycosaminoglycan from A. japonicus (AjFG) has shown multiple pharmacological activities. However, results from studies on the structure of AjFG are still controversial. In this study, the deaminative depolymerization method that is glycosidic bond-selective was used to prepare the depolymerized products from AjFG (dAjFG), and then a series of purified oligosaccharide fragments such as tri-, hexa-, nona-, and dodecasaccharides were obtained from dAjFG by gel permeation chromatography. The 1D/2D NMR and ESI-MS spectrometry analyses showed that these oligosaccharides had the structural formula of l-FucS-α1,3-d-GlcA-ß1,3-{d-GalNAc4S6S-ß1,4-[l-FucS-α1,3-]d-GlcA-ß1,3-}n-d-anTal-diol4S6S (n = 0, 1, 2, 3; FucS represents Fuc2S4S, Fuc3S4S, or Fuc4S). Thus, the unambiguous structure of native AjFG can be rationally deduced: it had the backbone of {-4-d-GlcA-ß1,3-d-GalNAc4S6S-ß1-}n, which is similar to chondroitin sulfate E, and each d-GlcA residue in the backbone was branched with a l-FucS monosaccharide at O-3. Bioactivity assays confirmed that dAjFG and nonasaccharides and dodecasaccharides from AjFG had potent anticoagulant activity by intrinsic FXase inhibition while avoiding side effects such as FXII activation and platelet aggregation.


Asunto(s)
Anticoagulantes/farmacología , Glicosaminoglicanos/química , Glicosaminoglicanos/farmacología , Oligosacáridos/farmacología , Stichopus/química , Animales , Anticoagulantes/química , Coagulación Sanguínea/efectos de los fármacos , Secuencia de Carbohidratos , Factor XII/metabolismo , Humanos , Estructura Molecular , Oligosacáridos/química , Tiempo de Tromboplastina Parcial , Agregación Plaquetaria/efectos de los fármacos , Relación Estructura-Actividad
17.
Int J Mol Sci ; 20(6)2019 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-30901838

RESUMEN

As core components of ABA signaling pathway, SnRK2s (Sucrose nonfermenting1⁻Related protein Kinase 2) bind to and phosphorylate AREB/ABF (ABA responsive element binding protein/ABRE-binding factor) transcriptional factors, particularly bZIPs (basic region-leucine zipper), to participate in various biological processes, including flowering. Rice contains 10 SnRK2 members denoted as SAPK1-10 (Stress-Activated Protein Kinase) and dozens of bZIPs. However, which of the SAPKs and bZIPs pair and involve in ABA signaling remains largely unknown. In this study, we carried out a systematical protein-protein interactomic analysis of 10 SAPKs and 9 ABA-inducible bZIPs using yeast-two-hybrid technique, and identified 14 positive interactions. The reliability of Y2H work was verified by in vitro pull-down assay of the key flowering regulator bZIP77 with SAPK9 and SAPK10, respectively. Moreover, SAPK10 could phosphorylate bZIP77 in vitro. Over-expression of SAPK10 resulted in earlier flowering time, at least partially through regulating the FAC-MADS15 pathway. Conclusively, our results provided an overall view of the SAPK-bZIP interactions, and shed novel lights on the mechanisms of ABA-regulated rice flowering.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Flores/fisiología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Oryza/fisiología , Proteínas de Plantas/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Regulación de la Expresión Génica de las Plantas , Fenotipo , Fosforilación , Unión Proteica , Mapeo de Interacción de Proteínas
18.
Int J Mol Sci ; 21(1)2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31905829

RESUMEN

Cyclin-dependent kinase inhibitors known as KRPs (kip-related proteins) control the progression of plant cell cycles and modulate various plant developmental processes. However, the function of KRPs in rice remains largely unknown. In this study, two rice KRPs members, KRP1 and KRP2, were found to be predominantly expressed in developing seeds and were significantly induced by exogenous abscisic acid (ABA) and Brassinosteroid (BR) applications. Sub-cellular localization experiments showed that KRP1 was mainly localized in the nucleus of rice protoplasts. KRP1 overexpression transgenic lines (OxKRP1), krp2 single mutant (crkrp2), and krp1/krp2 double mutant (crkrp1/krp2) all exhibited significantly smaller seed width, seed length, and reduced grain weight, with impaired seed germination and retarded early seedling growth, suggesting that disturbing the normal steady state of KRP1 or KRP2 blocks seed development partly through inhibiting cell proliferation and enlargement during grain filling and seed germination. Furthermore, two cyclin-dependent protein kinases, CDKC;2 and CDKF;3, could interact with KRP1 in a yeast-two-hybrid system, indicating that KRP1 might regulate the mitosis cell cycle and endoreduplication through the two targets. In a word, this study shed novel insights into the regulatory roles of KRPs in rice seed maturation and germination.


Asunto(s)
Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/metabolismo , Germinación/fisiología , Oryza/metabolismo , Semillas/metabolismo , Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brasinoesteroides , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Proliferación Celular , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/genética , Quinasas Ciclina-Dependientes/metabolismo , Grano Comestible/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Germinación/genética , Mutación , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Protoplastos/metabolismo
19.
Chemistry ; 24(10): 2365-2369, 2018 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-29315875

RESUMEN

Three new proton conductors with simple structures based on isolated olyoxometalate anions as well as protonated imidazole and benzimidazole, namely, NNU-6-8, have been successfully prepared by hydrothermal reaction. We could control the number of proton sources by selecting different types and changing the charges of POM anions. The single crystal sample of NNU-6 along a-axis shows a highest proton conductivity of 1.91×10-2  S cm-1 , which is two and three orders of magnitude higher than that of 2.42×10-4 and 8.90×10-5  S cm-1 along b- and c-axes, respectively, due to the more unobstructed H-bonding network and stronger π-π stacking between benzimidazole rings as proton-transferring pathway along a-axis than that along b and c axes. It is a straightforward model to understand the metaphysical proton-conducting process, and this is the first time to put forward the idea that π-π stacking could assist proton transfer and be in favor of proton conduction, which has been demonstrated by calculating potential energy surfaces of proton transfer between benzimidazole molecules.

20.
Sensors (Basel) ; 16(7)2016 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-27399704

RESUMEN

Visual odometry (VO) estimation from blurred image is a challenging problem in practical robot applications, and the blurred images will severely reduce the estimation accuracy of the VO. In this paper, we address the problem of visual odometry estimation from blurred images, and present an adaptive visual odometry estimation framework robust to blurred images. Our approach employs an objective measure of images, named small image gradient distribution (SIGD), to evaluate the blurring degree of the image, then an adaptive blurred image classification algorithm is proposed to recognize the blurred images, finally we propose an anti-blurred key-frame selection algorithm to enable the VO robust to blurred images. We also carried out varied comparable experiments to evaluate the performance of the VO algorithms with our anti-blur framework under varied blurred images, and the experimental results show that our approach can achieve superior performance comparing to the state-of-the-art methods under the condition with blurred images while not increasing too much computation cost to the original VO algorithms.

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