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1.
Food Chem ; 368: 130772, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34399182

RESUMO

Macrolepiota albuminosa (Berk.) Pegler is abundant in active polysaccharides, but little is known about their structures and solution properties. In this study, water-extracted polysaccharides from M. albuminosa (MAWP) were purified into three fractions with structural heterogeneity, which was attributed to the diversity in molecular weight, monosaccharide composition and linkage patterns, further affecting their solution properties. Methylation and NMR analysis revealed MAWP-60p and MAWP-70 were a 3-O-methylated glucomannogalactan and a previously unreported glucomannogalactan, whereas MAWP-80 was elucidated as a branched galactoglucan. Besides, three fractions exhibited random coil conformation in aqueous solution, while MAWP-60p had the highest viscosity due to its highest molecular weight, mean square radius of gyration (Rg) and O-methyl group attached to the backbone. The molecular weight, monosaccharide composition and glycosidic linkages might be the major contributors to the flexibility, molecular size and stereochemistry of mushroom polysaccharide chains.


Assuntos
Agaricales , Polissacarídeos , Carboidratos da Dieta , Peso Molecular , Monossacarídeos , Viscosidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-34363866

RESUMO

The accumulation of amyloid-ß (Aß) peptides in the brain is considered to be the initial event in the Alzheimer's disease (AD). Neurotoxicity mediated by Aß has been demonstrated to damage the cognitive function. In the present study, we sought to determine the effects of O-1602, a specific G-protein coupled receptor 55 (GPR55) agonist, on the impairment of learning and memory induced by intracerebroventricular (i.c.v.) of Aß1-42 (400 pmol/mouse) in mice. Our results showed that i.c.v. injection of aggregated Aß1-42 into the brain of mice resulted in cognitive impairment and neurotoxicity. In contrast, O-1602 (2.0 or 4.0 µg/mouse, i.c.v.) can improve memory impairment induced by Aß1-42 in the Morris water maze (MWM), and novel object recognition (NOR) tests. Besides, we found that O-1602 reduced the activity of ß-secretase 1 (BACE1) and the level of soluble Aß1-42 in the hippocampus and frontal cortex. Importantly, O-1602 treatment reversed Aß1-42-induced GPR55 down-regulation, decreased pro-inflammatory cytokines, and the level of malondialdehyde (MDA), increased the levels of glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT), as well as suppressed apoptosis as indicated by decreased TUNEL-positive cells, and increased the ratio of Bcl-2/Bax. O-1602 treatment also pronouncedly ameliorated synaptic dysfunction by promoting the upregulation of PSD-95 and synaptophysin (SYN) proteins. Moreover, O-1602 concurrently down regulated the protein levels of RhoA, and ROCK2, the critical proteins in the RhoA/ROCK2 pathway. This study indicates that O-1602 may reverse Aß1-42-induced cognitive impairment and neurotoxicity in mice by inhibiting RhoA/ROCK2 pathway. Taken together, these findings suggest that GPR55 could be a novel and promising target for the treatment of AD.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34450276

RESUMO

The kisspeptin system, which lies upstream of the hypothalamic-pituitary-gonadal (HPG) axis, is believed to function as a regulator of reproduction in teleosts. In this study, we isolated and characterized kiss2 and its receptor kissr2 in largemouth bass (Micropterus salmoides). The complete coding sequences of kiss2 and kissr2 were 375 and 1134 bp long and encoded precursor proteins 124 and 377 amino acid long, respectively. Real-time PCR showed that kiss2 and kissr2 were primarily expressed in the HPG axis. The expression profile of kiss2 and kissr2 varied with gonadal development, with the highest and lowest expression levels being detected during the immature and final maturation stages, respectively. Intraperitoneal injection of exogenous Kiss2-10 peptide increased the transcript levels of gnrh3, kissr2, fshß, lhß, ar, and er2 within 24 h (p < 0.05), as well as plasma levels of 17ß-estradiol and testosterone. Histological analysis indicated that chronic administration of exogenous Kiss2-10 peptide accelerated vitellogenesis in females and spermatogenesis in males. Further, in situ hybridization revealed that kiss2 is expressed in the ooplasm and vitelline envelope of oocytes and the spermatocytes of testes. In addition, experiments using gonad tissue primary cell cultures indicated that exogenous Kiss2-10 peptide stimulates the expression of reproduction-related genes. Collectively, our findings indicate that the kiss2/kissr2 system in largemouth bass is involved in regulating gonadal development through the HPG axis.

4.
J Affect Disord ; 297: 593-601, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34718040

RESUMO

BACKGROUND: Psychosomatic symptoms are often related with behaviors. However, the association between different behaviors and their latent patterns and psychosomatic health status is unclear. Current study aimed to identify the patterns of six behaviors and explore the association between different patterns and psychosomatic symptoms in a school-based sample of Chinese adolescents. METHODS: From November 2015 to January 2016, the study enrolled 22,628 students from six cities in China (15.36 ± 1.79 years). Six behaviors [unintentional injury (UI), non-suicidal self-injury (NSSI), suicidal behaviors (SB), drinking, smoking, screen time (ST)] and psychosomatic symptoms (psychological and physical symptoms) were measured by self-report validated questionnaires. RESULTS: Six behaviors were all related to psychosomatic symptoms, among which SB was the strongest. Four patterns of behaviors were be identified as follows: low-risk pattern (64.0%), substance use pattern (4.5%), injury pattern (28.8%) and high-risk pattern (2.7%). Logistic regression analysis of psychological symptoms indicated that compared with low-risk pattern, high-risk pattern had the highest risk, followed by injury pattern, substance use pattern showed the lowest risk. Compared with low-risk pattern, the results of physical symptoms suggested the degree of risk was high-risk pattern, injury pattern and substance use pattern, respectively. LIMITATIONS: Cross-sectional data were used in the study that could not evaluate causal relationships between six behaviors and psychosomatic symptoms. CONCLUSIONS: Six behaviors and their latent patterns are related to psychosomatic symptoms among Chinese adolescents differently, so different intervention and prevention protocol need to be taken for different patterns of adolescents.

5.
JAMA Cardiol ; 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34851361

RESUMO

Importance: African American individuals have disproportionate rates of coronary heart disease (CHD) but lower levels of coronary artery calcium (CAC), a marker of subclinical CHD, than non-Hispanic White individuals. African American individuals may have distinct metabolite profiles associated with incident CHD risk compared with non-Hispanic White individuals, and examination of these differences could highlight important processes that differ between them. Objectives: To identify novel biomarkers of incident CHD and CAC among African American individuals and to replicate incident CHD findings in a multiethnic cohort. Design, Setting, and Participants: This analysis targeted plasma metabolomic profiling of 2346 participants in the Jackson Heart Study (JHS), a prospective population-based cohort study that included 5306 African American participants who were examined at baseline (2000-2004) and 2 follow-up visits. Replication of CHD-associated metabolites was sought among 1588 multiethnic participants from the Women's Health Initiative (WHI), a prospective population-based multiethnic cohort study of 161 808 postmenopausal women who were examined at baseline (1991-1995) and ongoing follow-up visits. Regression analyses were performed for each metabolite to examine the associations with incident CHD and CAC scores. Data were collected from the WHI between 1994 and 2009 and from the JHS between 2000 and 2015. All data were analyzed from November 2020 to August 2021. Exposures: Plasma metabolites. Main Outcomes and Measures: Incident CHD was defined as definite or probable myocardial infarction or definite fatal CHD in both the JHS and WHI cohorts. In the JHS cohort, silent myocardial infarction between examinations (as determined by electrocardiography) and coronary revascularization were included in the incident CHD analysis. Coronary artery calcium was measured using a 16-channel computed tomographic system and reported as an Agatston score. Results: Among 2346 African American individuals in the JHS cohort, the mean (SD) age was 56 (13) years, and 1468 individuals (62.6%) were female. Among 1588 postmenopausal women in the WHI cohort, the mean (SD) age was 67 (7) years; 217 individuals (13.7%) self-identified as African American, 1219 (76.8%) as non-Hispanic White, and 152 (9.6%) as other races or ethnicities. In the fully adjusted model including 1876 individuals, 46 of 303 targeted metabolites were associated with incident CHD (false discovery rate q <0.100). Data for 32 of the 46 metabolites were available in the WHI cohort, and 13 incident CHD-associated metabolites from the JHS cohort were replicated in the WHI cohort. A total of 1439 participants from the JHS cohort with available CAC scores received metabolomic profiling. Nine metabolites were associated with CAC scores. Minimal overlap was found between the results from the incident CHD and CAC analyses, with only 3 metabolites shared between the 2 analyses. Conclusions and Relevance: This cohort study identified metabolites that were associated with incident CHD among African American individuals, including 13 incident CHD-associated metabolites that were replicated in a multiethnic population and 9 novel metabolites that included N-acylamides, leucine, and lipid species. These findings may help to elucidate common and distinct metabolic processes that may be associated with CHD among individuals with different self-identified race.

6.
Front Psychol ; 12: 746608, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744920

RESUMO

Parental support is essential to children's motivation and academic functioning. However, few studies have investigated the pathways linking perceived parental support to children's achievement in reading during adolescence. This study aims to fill this gap by systematically investigating the relationships among perceived support from parents, adolescents' motivational beliefs, and reading proficiency based on Bandura's social cognitive theory. A range of motivational processes are explored, including self-efficacy, goals, and values. Using the China sample from the Programme for International Student Assessment (PISA) 2018, which includes 12,058 adolescents from 361 schools, this study proposed two competing models based on different accounts of self-efficacy beliefs. Multilevel path analysis is adopted as the analytic method. The results suggest that perceived support from parents has a statistically significant but negligible relationship with adolescents' reading proficiency. However, this relationship is mediated by nuanced pathways such as self-efficacy beliefs, mastery goal orientation, and reading enjoyment. Findings of this study provide evidence in support of the top-down theory of self-efficacy in the reading context and also contribute to a better understanding of the interactions between different motivational processes. Theoretical and practical implications of this study are discussed, and suggestions for future research are offered.

7.
Food Sci Nutr ; 9(11): 6294-6306, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34760259

RESUMO

The process of fermentation renders the superior quality of mulberry wine based on the microorganisms utilized. The present study aimed at investigating the changes and correlation between phenols and product quality of mulberry wine fermented with Lactiplantibacillus plantarum and Saccharomyces cerevisiae combinatorially. Total anthocyanins concentration (TAC), polyphenols concentration (TPC), flavonoids concentration (TFC), and antioxidant capacity decreased significantly with high correlation in the fermentation process. TAC gradually reduced with a loss rate of 47.98% from 0 to third day of fermentation. Fermented mulberry wine obtained indicated a dynamic balance due to the presence of p-hydroxybenzoic acids as compared to the primary phenolic constituent. Chlorogenic acid usually presents in mulberry juice. The relative intensity of sourness was the most prominent and reached the maximum (10.93) on day 2 of fermentation. A total of 21 volatile esters were quantified (6621.59 µg/L), which contributed significantly to the aroma of mulberry wine. The enhanced quality of fermented mulberry wine showed contraindications with decreased constituents and escalated wine quality. Rather than usual single inoculum, fermentation combination of LAB and yeast holistically influenced the color, taste, fragrance, phenolic profiles, and antioxidant properties in mulberry wine, ensuring palatability and fit for commercialization prospects.

8.
Cell Rep ; 37(6): 109987, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34758320

RESUMO

CENP-A (centromeric protein A), a histone H3 variant, specifies centromere identity and is essential to centromere maintenance. Little is known about how protein levels of CENP-A are controlled in mammalian cells. Here, we report that the phosphorylation of CENP-A Ser68 primes the ubiquitin-proteasome-mediated proteolysis of CENP-A during mitotic phase in human cultured cells. We identify two major polyubiquitination sites that are responsible for this phosphorylation-dependent degradation. Substituting the two residues, Lys49 and Lys124, with arginines abrogates proper CENP-A degradation and results in CENP-A mislocalization to non-centromeric regions. Furthermore, we find that DCAF11 (DDB1 and CUL4 associated factor 11/WDR23) is the E3 ligase that specifically mediates the observed polyubiquitination. Deletion of DCAF11 hampers CENP-A degradation and causes its mislocalization. We conclude that the Ser68 phosphorylation plays an important role in regulating cellular CENP-A homeostasis via DCAF11-mediated degradation to prevent ectopic localization of CENP-A during the cell cycle.

9.
J Cancer ; 12(23): 7190-7200, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34729120

RESUMO

Background: This study aimed to evaluate the role of plasma microRNA panel (miR-122, miR-192, miR-21, miR-223, miR-26a, miR-27a and miR-801) for prediction and surveillance of early tumor recurrence in hepatocellular carcinoma (HCC) patients who had undergone liver transplantation (LT). Methods: The expression of plasma microRNA panel was assayed in 193 HCC patients (training cohort, n =151; validation cohort, n = 42). Sensitivity and specificity for detecting post-transplant HCC recurrence, and the relationship of microRNA panel expression with clinical characteristics were analyzed accordingly. The prognostic value of microRNA panel was compared with that of AFP (alpha-fetoprotein) and DCP (Des-gamma-carboxyprothrombin). Cox regression analyses were used to evaluate independent prognostic factors. Results: In the training cohort, the rate of positive plasma microRNA panel status at 7-14 days after LT (late phase; 44.2%) decreased than that before (76.2%, P < 0.001) and 1-6 days after LT (early phase; 78.5%, P < 0.001). At late phase, positive microRNA panel status correlated with higher early tumor recurrence rate (one year after LT) than negative status (45.9% vs 10.7%; P < 0.001). Patients with persistent positive microRNA panel status both before and after LT had the highest early tumor recurrence rate in this cohort (54.9%, P < 0.001). The results were consistent in the validation cohort. Cox regression analysis found that positive plasma microRNA panel status at late phase was the only independent risk factor for early recurrence (HR: 4.903, 95% CI = 2.195 - 10.951; P < 0.001). Dynamic monitoring demonstrated plasma microRNA panel status changed from negative to positive earlier than AFP and DCP upon recurrence, and the median time between positivity of plasma microRNA and imaging evidence of recurrence was 2.4 (0.5-10.0) months. Conclusions: Plasma microRNA panel could be a noninvasive biomarker for prediction and surveillance of early tumor recurrence in HCC patients who have undergone LT.

10.
Mol Ecol Resour ; 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800349

RESUMO

The Jinjiang oyster Crassostrea ariakensis, naturally distributing in estuarine regions with low salinity, is an important economic and ecological species in China. However, studies on its genomics and population genetics remain lacking. Here, we assembled the chromosome-level genome of a female C. ariakensis and re-sequenced 261 individuals from five locations in China representing three typical habitats. The C. ariakensis genome was 662.9 Mb with contig N50 length of 5.9 Mb using PacBio HiFi-CCS long reads, and 99.83% sequences were anchored onto 10 pseudo-chromosomes using Hi-C data. A total of 26,354 protein-coding genes were predicted. We identified three significantly expanded gene families which are closely associated with osmotic pressure regulation, including CDO, SLC13 and SDR. Population structure analysis revealed that the C. ariakensis from five locations were clustered into three typical groups (northern, southern and Shanghai) (K=3) and their phylogenetic relationship was consistently correlated to their geographical distribution. Furtherly, the differentiation between northern and southern groups was clearly demonstrated by estimated population differentiation coefficient (FST = 0.1154), and the PSMC distribution showed the two groups of effective population size separated at 0.1 MYA. Meanwhile gene flow from southern to Shanghai was detected. Selective sweep analysis between northern and southern group detected genes associated with heat response and salinity adaptation. This study could provide valuable genomic resources and information for further research on the molecular evolution, genetic breeding, biological function and evolutionary adaptation of C. ariakensis.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34769930

RESUMO

Reuse of waste from Hami melon (cantaloupes) straws (HS) mingled with polypropylene (PP) ropes is necessary and beneficial to mitigate environmental pollution. The objective of this study was to investigate the characteristics and mechanisms of Cd2+ adsorption on biochars produced by co-pyrolysis of HS-PP with various mixing ratios. N2-sorption, scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), elemental analysis, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravity, and differential thermal gravity (TG/DTG) were applied to evaluate the physicochemical properties of materials. Batch adsorption experiments were carried out for investigating the effects of initial pH, Cd2+ concentration, and adsorption time. It was found that the Langmuir and pseudo-second-order models fitted best for the experimental data, indicating the dominant adsorption of co-pyrolysis biochars is via monolayer adsorption. Biochar derived at 4/1 mixing ratio of HS/PP by weight percentage had the highest adsorption capacity of 108.91 mg·g-1. Based on adsorption isotherm and kinetic analysis in combined with EDS, FTIR, and XRD analysis, it was concluded that the main adsorption mechanism of co-pyrolysis biochar involved the surface adsorption, cation exchange, complexation of Cd2+ with surface functional groups, and chemical precipitation. This study also demonstrates that agricultural wastes to biochar is a sustainable way to circular economy.


Assuntos
Cucumis melo , Cucurbitaceae , Poluentes Químicos da Água , Adsorção , Cádmio , Carvão Vegetal , Cinética , Polipropilenos , Pirólise , Poluentes Químicos da Água/análise
13.
Front Cardiovasc Med ; 8: 760140, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805315

RESUMO

In recent years, the vital role of genetic factors in human diseases have been widely recognized by scholars with the deepening of life science research, accompanied by the rapid development of gene-editing technology. In early years, scientists used homologous recombination technology to establish gene knock-out and gene knock-in animal models, and then appeared the second-generation gene-editing technology zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs) that relied on nucleic acid binding proteins and endonucleases and the third-generation gene-editing technology that functioned through protein-nucleic acids complexes-CRISPR/Cas9 system. This holds another promise for refractory diseases and genetic diseases. Cardiovascular disease (CVD) has always been the focus of clinical and basic research because of its high incidence and high disability rate, which seriously affects the long-term survival and quality of life of patients. Because some inherited cardiovascular diseases do not respond well to drug and surgical treatment, researchers are trying to use rapidly developing genetic techniques to develop initial attempts. However, significant obstacles to clinical application of gene therapy still exists, such as insufficient understanding of the nature of cardiovascular disease, limitations of genetic technology, or ethical concerns. This review mainly introduces the types and mechanisms of gene-editing techniques, ethical concerns of gene therapy, the application of gene therapy in atherosclerosis and inheritable cardiovascular diseases, in-stent restenosis, and delivering systems.

14.
J Cell Sci ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34817059

RESUMO

The disruption of endosomal actin architecture negatively affects endocytic recycling. However, the underlying homeostatic mechanisms that regulate actin organization during recycling remain unclear. In this study, we identified a synergistic endosomal actin assembly restricting mechanism in C. elegans involving WTS-1/LATS kinase, which is a core component of the Hippo pathway. WTS-1 resides on the sorting endosomes and colocalizes with the actin polymerization regulator PTRN-1/CAMSAPs. We observed an increase in PTRN-1-labeled structures in WTS-1-deficient cells, indicating that WTS-1 can limit the endosomal localization of PTRN-1. Accordingly, the actin overaccumulation phenotype in WTS-1-depleted cells was mitigated by the associated PTRN-1 loss. We further demonstrated that recycling defects and actin overaccumulation in WTS-1-deficient cells were reduced by the overexpression of constitutively active UNC-60A/cofilin(S3A), which aligns with the role of LATS as a positive regulator of cofilin activity. Altogether, our data confirmed previous findings, and we proposed an additional model: WTS-1 acts alongside the UNC-60A/cofilin-mediated actin disassembly to restrict the assembly of endosomal F-actin by curbing PTRN-1 dwelling on endosomes, preserving recycling transport.

15.
Genes Dev ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34819355

RESUMO

Chromosomal duplication requires de novo assembly of nucleosomes from newly synthesized histones, and the process involves a dynamic network of interactions between histones and histone chaperones. sNASP and ASF1 are two major histone H3-H4 chaperones found in distinct and common complexes, yet how sNASP binds H3-H4 in the presence and absence of ASF1 remains unclear. Here we show that, in the presence of ASF1, sNASP principally recognizes a partially unfolded Nα region of histone H3, and in the absence of ASF1, an additional sNASP binding site becomes available in the core domain of the H3-H4 complex. Our study also implicates a critical role of the C-terminal tail of H4 in the transfer of H3-H4 between sNASP and ASF1 and the coiled-coil domain of sNASP in nucleosome assembly. These findings provide mechanistic insights into coordinated histone binding and transfer by histone chaperones.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34738216

RESUMO

Landfilled municipal solid waste (MSW) in developing countries generally produces a large amount of leachate due to high moisture content. The estimation of leachate production and level is of great importance to the capacity design of leachate treatment plants and the stability analysis of landfills. In this study, the leachate production ratios (the ratio of leachate mass to waste mass) in different countries and cities were first summarized to reveal the basic status of leachate generation. Then, a model was established to calculate the leachate production and level that considers the rainfall infiltration and the water released from MSW due to both primary and secondary compression (ignored in previous models). Finally, the proposed model was used in a case study of Laogang Landfill in Shanghai, China. It was found that the leachate proportion produced by compression was much higher compared with that produced by rainfall infiltration, ranging from 49 (rainy season) to 93% (dry season). The leachate released from waste due to secondary compression accounted for a high proportion (up to 25%) of the total leachate production, especially for aged MSW. The calculated leachate discharge amount and leachate level were close to the measured values because the possible low permeability layer at the bottom of the landfill was considered in this model.

18.
Clin Chim Acta ; 523: 525-531, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34748781

RESUMO

BACKGROUND: Liver cirrhosis is closely related to the abnormal liver function and occurrence of liver cancer. Accurate non-invasive assessment of liver cirrhosis is of great significance for preventing disease progression and treatment decision-making. We aim to develop and validate a non-invasive diagnostic model for liver cirrhosis in patients with chronic hepatitis B (CHB). METHODS: From July 2015 to April 2017, seven-hundred fifty-four patients with primary HBV-related liver cancer who underwent hepatectomy were reprospectively recruited. All patients were examined with 2D-SWE and serologic testing preoperatively, which were utilized for measurement of liver stiffness and serum fibrosis models. The stage of liver fibrosis was evaluated using a resected liver specimen. Least absolute shrinkage and selection operator (Lasso) regression was used for feature selection and binary logistic regression analysis was chosen to build a diagnostic model, which was presented as a nomogram and evaluated for calibration, discrimination and clinical usefulness. The performance of noninvasive model was then prospectively validated in an independent cohort (361 patients) by the ROC curve analysis. RESULTS: The diagnostic model, which consists of 5 selected clinical characteristics (PIII-NP, IV-C, Hyaluronan, Platelet and Liver stiffness), showed the strongest correlation with liver fibrosis stage (ρ = 0.702, P < 0.05). Compared with APRI, FIB-4, King's Score, and Forns Index, the model presented the optimal discrimination and the best predictive performance with the highest AUC in the training cohort (0.866, 95%CI 0.840-0.892, P < 0.05) and validation cohorts (0.852, 95%CI 0.813-0.890, P < 0.05). Decision curve analysis demonstrated that nomogram based on the model was extremely useful for diagnosing cirrhosis in patients with chronic hepatitis B. CONCLUSION: This study proposes a non-invasive diagnostic model that incorporates the clinical predictors which can be conveniently used in the individualized diagnosis of HBV-related liver cirrhosis.

19.
Plant Commun ; 2(6): 100247, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34778752

RESUMO

Pecan (Carya illinoinensis) is a tree nut crop of worldwide economic importance that is rich in health-promoting factors. However, pecan production and nut quality are greatly challenged by environmental stresses such as the outbreak of severe fungal diseases. Here, we report a high-quality, chromosome-scale genome assembly of the controlled-cross pecan cultivar 'Pawnee' constructed by integrating Nanopore sequencing and Hi-C technologies. Phylogenetic and evolutionary analyses reveal two whole-genome duplication (WGD) events and two paleo-subgenomes in pecan and walnut. Time estimates suggest that the recent WGD event and considerable genome rearrangements in pecan and walnut account for expansions in genome size and chromosome number after the divergence from bayberry. The two paleo-subgenomes differ in size and protein-coding gene sets. They exhibit uneven ancient gene loss, asymmetrical distribution of transposable elements (especially LTR/C opia and LTR/G y psy), and expansions in transcription factor families (such as the extreme pecan-specific expansion in the far-red impaired response 1 family), which are likely to reflect the long evolutionary history of species in the Juglandaceae. A whole-genome scan of resequencing data from 86 pecan scab-associated core accessions identified 47 chromosome regions containing 185 putative candidate genes. Significant changes were detected in the expression of candidate genes associated with the chitin response pathway under chitin treatment in the scab-resistant and scab-susceptible cultivars 'Excell' and 'Pawnee'. These findings enable us to identify key genes that may be important susceptibility factors for fungal diseases in pecan. The high-quality sequences are valuable resources for pecan breeders and will provide a foundation for the production and quality improvement of tree nut crops.

20.
Int Immunopharmacol ; 101(Pt B): 108335, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34781121

RESUMO

The accumulation of amyloid beta (Aß) in the brain is thought to be associated with cognitive deficits in Alzheimer's disease (AD). However, current methods to combat Aß neurotoxicity are still lacking. G protein-coupled receptor 17 (GPR17) has become a target for treating inflammation in brain diseases, but it is unclear whether it has a role in AD. Here, we investigated the effects of cangrelor, a GPR17 antagonist, on neurotoxicity and memory impairment induced by intracerebroventricular (i.c.v.) injection of Aß1-42 in mice. The behavior results showed that cangrelor (2.0 or 4.0 µg/mouse, i.c.v.) treatment reversed the deficits in memory and learning ability induced by Aß1-42 in mice. Importantly, we demonstrated for the first time that GPR17 expression in the hippocampus and frontal cortex is increased in response to Aß1-42 exposures. We also found that cangrelor treatment reduced the activity of ß-secretase 1 (BACE1) and the levels of soluble Aß1-42 in the hippocampus and frontal cortex. Meanwhile, cangrelor treatment suppressed oxidative stress induced by Aß1-42, as proved by reduced production of malondialdehyde (MDA), and increased glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT), and promoted the expression of nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1). Furthermore, cangrelor also suppressed Aß1-42-induced neuroinflammation, characterized by suppressed activation of microglia, decreased the levels of pro-inflammatory cytokines, and nuclear translocation of NF-κB p65, as well as ameliorated synaptic deficits by promoting the upregulation of synaptic proteins, and increasing the number of Golgi-Cox stained dendritic spines. These results suggest that cangrelor may reverse Aß1-42-induced cognition deficits via inhibiting oxidative stress, neuroinflammation, and synaptic dysfunction mediated by Nrf2/HO-1 and NF-κB signaling.

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