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1.
Front Neurol ; 15: 1374159, 2024.
Article in English | MEDLINE | ID: mdl-38721117

ABSTRACT

Background: Evidence of the relationship between platelet count and 30-day in-hospital mortality in ICU stroke patients is still scarce. Therefore, the purpose of this study was to explore the relationship between platelet count and 30-day in-hospital mortality among ICU stroke patients. Methods: We conducted a multicenter retrospective cohort study using data from 8,029 ICU stroke patients in the US eICU-CRD v2.0 database from 2014 to 2015. Utilizing binary logistic regression, smooth curve fitting, and subgroup analyses, we examined the link between platelet count and 30-day in-hospital mortality. Results: The 30-day in-hospital mortality prevalence was 14.02%, and the mean platelet count of 223 × 109/L. Adjusting for covariates, our findings revealed an inverse association between platelet count and 30-day in-hospital mortality (OR = 0.975, 95% CI: 0.966, 0.984). Subgroup analyses supported the robustness of these results. Moreover, a nonlinear relationship was observed between platelet count and 30-day in-hospital mortality, with the inflection point at 163 × 109/L. On the left side of the inflection point, the effect size (OR) was 0.92 (0.89, 0.95), while on the right side, the relationship was not statistically significant. Conclusion: This study establishes an independent negative association between platelet count and 30-day in-hospital mortality in ICU stroke patients. Furthermore, a nonlinear relationship with a saturation effect was identified, suggesting that maintaining the platelet count around 163 × 109/L can reduce 30-day in-hospital mortality in these patients.

2.
Neurosci Lett ; 812: 137380, 2023 08 24.
Article in English | MEDLINE | ID: mdl-37423466

ABSTRACT

BACKGROUND: Brain-derived neurotrophic factor (BDNF) promotes neuroprotection and neuroregeneration. BDNF enhances the survival of dopaminergic neurons and improves dopaminergic neurotransmission and motor performance in patients with Parkinson's disease (PD). However, the association between BDNF levels and rapid eye movement (REM) sleep behavior disorder (RBD) in PD patients has received limited attention. METHODS: We employed the Rapid Eye Movement Sleep Behavior Disorder Questionnaire-Hong Kong version (RBDQ-HK) and the Rapid Eye Movement Sleep Behavior Disorder Screening Questionnaire (RBDSQ) for RBD diagnosis. Patients were categorized into three groups: healthy controls (n = 53), PD patients without RBD (PD-nRBD; n = 56), and PD patients with RBD (PD-RBD; n = 45). Serum BDNF concentrations, demographic information, medical history, and motor/non-motor manifestations were compared between the three groups. Logistic regression analysis was performed to identify independent factors associated with PD and RBD. P-trend analysis was used to assess the relationship between BDNF levels and the risk of PD and RBD onset. Interaction effects were analyzed between BDNF, patients' age, and gender on the risk of RBD onset in PD patients. RESULTS: Our findings indicate that serum BDNF levels were significantly lower in PD patients compared to healthy controls (p < 0.001). PD-RBD patients exhibited higher motor symptom scores (UPDRS III) than PD-nRBD patients (p = 0.021). Additionally, the PD-RBD group demonstrated lower cognitive function scores as measured by the Montreal Cognitive Assessment (MoCA) (p < 0.001) and Mini-Mental State Examination (MMSE) (p = 0.015). PD-RBD patients displayed significantly lower BDNF levels compared to both PD-nRBD and healthy control groups (p < 0.001). Univariate and multivariate logistic regression analyses showed that reduced BDNF levels were associated with an increased risk of RBD in PD patients (p = 0.005). P-trend analysis further confirmed the progressive relationship between decreased BDNF levels and the risk of PD and RBD onset. Furthermore, our interaction analysis highlighted the importance of monitoring younger PD patients with low serum BDNF levels for potential RBD onset. CONCLUSIONS: This study illustrates that decreased serum BDNF levels may be linked to the development of RBD in PD patients, highlighting the potential utility of BDNF as a biomarker in clinical practice.


Subject(s)
Parkinson Disease , REM Sleep Behavior Disorder , Humans , REM Sleep Behavior Disorder/diagnosis , Brain-Derived Neurotrophic Factor , Polysomnography , Surveys and Questionnaires
3.
Nat Commun ; 14(1): 3462, 2023 06 12.
Article in English | MEDLINE | ID: mdl-37308495

ABSTRACT

O-Methylated stilbenes are prominent nutraceuticals but rarely produced by crops. Here, the inherent ability of two Saccharinae grasses to produce regioselectively O-methylated stilbenes is reported. A stilbene O-methyltransferase, SbSOMT, is first shown to be indispensable for pathogen-inducible pterostilbene (3,5-bis-O-methylated) biosynthesis in sorghum (Sorghum bicolor). Phylogenetic analysis indicates the recruitment of genus-specific SOMTs from canonical caffeic acid O-methyltransferases (COMTs) after the divergence of Sorghum spp. from Saccharum spp. In recombinant enzyme assays, SbSOMT and COMTs regioselectively catalyze O-methylation of stilbene A-ring and B-ring respectively. Subsequently, SOMT-stilbene crystal structures are presented. Whilst SbSOMT shows global structural resemblance to SbCOMT, molecular characterizations illustrate two hydrophobic residues (Ile144/Phe337) crucial for substrate binding orientation leading to 3,5-bis-O-methylations in the A-ring. In contrast, the equivalent residues (Asn128/Asn323) in SbCOMT facilitate an opposite orientation that favors 3'-O-methylation in the B-ring. Consistently, a highly-conserved COMT is likely involved in isorhapontigenin (3'-O-methylated) formation in wounded wild sugarcane (Saccharum spontaneum). Altogether, our work reveals the potential of Saccharinae grasses as a source of O-methylated stilbenes, and rationalize the regioselectivity of SOMT activities for bioengineering of O-methylated stilbenes.


Subject(s)
Saccharum , Sorghum , Poaceae , Methylation , Phylogeny
4.
Nat Commun ; 14(1): 1477, 2023 03 17.
Article in English | MEDLINE | ID: mdl-36932092

ABSTRACT

Spatial analysis of microbiomes at single cell resolution with high multiplexity and accuracy has remained challenging. Here we present spatial profiling of a microbiome using sequential error-robust fluorescence in situ hybridization (SEER-FISH), a highly multiplexed and accurate imaging method that allows mapping of microbial communities at micron-scale. We show that multiplexity of RNA profiling in microbiomes can be increased significantly by sequential rounds of probe hybridization and dissociation. Combined with error-correction strategies, we demonstrate that SEER-FISH enables accurate taxonomic identification in complex microbial communities. Using microbial communities composed of diverse bacterial taxa isolated from plant rhizospheres, we apply SEER-FISH to quantify the abundance of each taxon and map microbial biogeography on roots. At micron-scale, we identify clustering of microbial cells from multiple species on the rhizoplane. Under treatment of plant metabolites, we find spatial re-organization of microbial colonization along the root and alterations in spatial association among microbial taxa. Taken together, SEER-FISH provides a useful method for profiling the spatial ecology of complex microbial communities in situ.


Subject(s)
Microbiota , In Situ Hybridization, Fluorescence/methods , Microbiota/genetics , Bacteria , RNA
6.
Microbiome ; 10(1): 233, 2022 12 16.
Article in English | MEDLINE | ID: mdl-36527160

ABSTRACT

Plant-microbe interactions dynamically affect plant growth, health, and development. The mechanisms underpinning these associations are-to a large extent-mediated by specialized host-derived secondary metabolites. Flavonoids are one of the most studied classes of such metabolites, regulating both plant development and the interaction with commensal microbes. Here, we provide a comprehensive review of the multiple roles of flavonoids in mediating plant-microbe interactions. First, we briefly summarize the general aspects of flavonoid synthesis, transport, and exudation in plants. Then, we review the importance of flavonoids regulating plant-microbe interactions and dynamically influencing the overall community assembly of plant-root microbiomes. Last, we highlight potential knowledge gaps in our understanding of how flavonoids determine the interactions between plants and commensal microbes. Collectively, we advocate the importance of advancing research in this area toward innovative strategies to effectively manipulate plant-microbiome composition, in this case, via flavonoid production and exudation in plant roots. Video Abstract.


Subject(s)
Microbiota , Rhizosphere , Flavonoids/metabolism , Plants/metabolism , Plant Roots/metabolism , Soil Microbiology
7.
Sleep Med ; 100: 133-138, 2022 12.
Article in English | MEDLINE | ID: mdl-36049407

ABSTRACT

BACKGROUND: Excessive daytime sleepiness (EDS) is a common sleep disorder in Parkinson's disease (PD), which seriously affects patients' quality of life. Repetitive transcranial magnetic stimulation (rTMS) can be used as an add-on therapy to a variety of non-motor symptoms of PD. However, little is known on the treatment of EDS in PD patients. OBJECTIVE: To explore the effects of low frequency rTMS over right dorsolateral prefrontal cortex (DLPFC) in the treatment of EDS in PD. METHODS: We conducted a sham-controlled, parallel study including 25 individuals of PD with possible EDS based on Epworth Sleepiness Scale (ESS ≥8 points) and randomly divided them into active group (n = 15) and sham group (n = 10). 1 Hz rTMS was administrated over right DLPFC for 10 consecutive days. In the active group, we further classified them into responsive group and non-responsive group according to change of ESS score in comparison with baseline. Clinical assessments on motor and non-motor symptoms were completed at baseline, at the end of treatment and 1 month after treatment. RESULTS: Compared to baseline, active group showed significant improvement on ESS score 10 days and 1 month after treatment (P < 0.05 for both). The percentage change of ESS score was positively related to disease duration during follow-up. No significant changes were observed on ESS score change in the sham group. Further analysis of individuals in the active group showed that, relative to those with non-response to rTMS, individuals with therapeutic response exhibited longer disease duration and lower baseline levodopa equivalent dose. CONCLUSION: Low frequency rTMS over right DLPFC may improve symptoms of EDS in PD.


Subject(s)
Disorders of Excessive Somnolence , Parkinson Disease , Humans , Disorders of Excessive Somnolence/etiology , Disorders of Excessive Somnolence/therapy , Dorsolateral Prefrontal Cortex , Parkinson Disease/therapy , Parkinson Disease/drug therapy , Prefrontal Cortex/physiology , Quality of Life , Transcranial Magnetic Stimulation
8.
Int J Mol Sci ; 23(13)2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35806361

ABSTRACT

Plant metabolism, including primary metabolism such as tricarboxylic acid cycle, glycolysis, shikimate and amino acid pathways as well as specialized metabolism such as biosynthesis of phenolics, alkaloids and saponins, contributes to plant survival, growth, development and interactions with the environment. To this end, these metabolic processes are tightly and finely regulated transcriptionally, post-transcriptionally, translationally and post-translationally in response to different growth and developmental stages as well as the constantly changing environment. In this review, we summarize and describe the current knowledge of the regulation of plant metabolism by alternative splicing, a post-transcriptional regulatory mechanism that generates multiple protein isoforms from a single gene by using alternative splice sites during splicing. Numerous genes in plant metabolism have been shown to be alternatively spliced under different developmental stages and stress conditions. In particular, alternative splicing serves as a regulatory mechanism to fine-tune plant metabolism by altering biochemical activities, interaction and subcellular localization of proteins encoded by splice isoforms of various genes.


Subject(s)
Alternative Splicing , Plants , Plants/genetics , Plants/metabolism , Protein Isoforms/metabolism , RNA Splice Sites
9.
Brain Sci ; 12(6)2022 Jun 07.
Article in English | MEDLINE | ID: mdl-35741631

ABSTRACT

Excellent response inhibition is the basis for outstanding competitive athletic performance, and sleep may be an important factor affecting athletes' response inhibition. This study investigates the effect of sleep deprivation on athletes' response inhibition, and its differentiating effect on non-athlete controls' performance, with the aim of helping athletes effectively improve their response inhibition ability through sleep pattern manipulation. Behavioral and event-related potential (ERP) data were collected from 36 participants (16 table tennis athletes and 20 general college students) after 36 h of sleep deprivation using ERP techniques and a stop-signal task. Sleep deprivation's different effects on response inhibition in the two groups were explored through repeated-measures ANOVA. Behavioral data showed that in a baseline state, stop-signal response time was significantly faster in table tennis athletes than in non-athlete controls, and appeared significantly longer after sleep deprivation in both groups. ERP results showed that at baseline state, N2, ERN, and P3 amplitudes were lower in table tennis athletes than in non-athlete controls, and corresponding significant decreases were observed in non-athlete controls after 36 h of sleep deprivation. Table tennis athletes showed a decrease in P3 amplitude and no significant difference in N2 and ERN amplitudes, after 36 h of sleep deprivation compared to the baseline state. Compared to non-athlete controls, table tennis athletes had better response inhibition, and the adverse effects of sleep deprivation on response inhibition occurred mainly in the later top-down motor inhibition process rather than in earlier automated conflict detection and monitoring.

10.
Neurosci Lett ; 782: 136692, 2022 06 21.
Article in English | MEDLINE | ID: mdl-35605904

ABSTRACT

OBJECTIVE: Previous studies have shown the essential role of inflammation in rapid eye movement (REM) sleep behavior disorder (RBD). However, the association of RBD in Parkinson's disease (PD) with peripheral blood inflammatory cytokines is still unknown. We investigated the relationship between inflammatory cytokines and the clinical characteristics of PD patients with RBD. METHODS: A total of 153 PD patients and 36 healthy controls were included in this study, and blood plasma was collected. PD patients were classified as PD with RBD (PD-RBD, n = 60) and PD without RBD (PD-nRBD, n = 93). Inflammatory factor levels were compared among the control, PD-RBD, and PD-nRBD groups. RESULTS: The PD-RBD group had significantly higher C-reactive protein (CRP) levels (P < 0.001), monocytes (P = 0.003), and neutrophil-to-lymphocyte ratio (NLR) (P < 0.001), whereas this group has lower lymphocytes levels (P < 0.001) and lymphocyte-to-monocyte ratio (LMR) (P < 0.001) than the PD-nRBD group. Univariate and multivariate logistic regression analysis indicated that LMR (P < 0.0001 odds ratio [OR] = 0.424) was a protective factor, whereas CRP (P < 0.001 OR = 2.326) was a risk factor for the PD-RBD group. PD-RBD patients had lower Montreal Cognitive Assessment (Beijing version) (MoCA) (P < 0.001) and Mini-Mental State Examination (MMSE) (P = 0.039) scores than PD-nRBD patients. CONCLUSIONS: Significant differences were found in inflammation levels between PD-RBD and PD-nRBD, suggesting that inflammatory factors are associated with the pathogenesis of RBD in PD patients. Thus, CRP and LMR levels may serve as biomarkers and predict the prognosis of PD patients with RBD.


Subject(s)
Parkinson Disease , REM Sleep Behavior Disorder , Cytokines , Humans , Inflammation/complications , Parkinson Disease/complications , Parkinson Disease/psychology , REM Sleep Behavior Disorder/complications , REM Sleep Behavior Disorder/diagnosis
11.
J Healthc Eng ; 2022: 6436256, 2022.
Article in English | MEDLINE | ID: mdl-35463681

ABSTRACT

Objective: The detection of Helicobacter pylori mutations that result in antimicrobial resistance can serve as a guideline of antimicrobial therapeutics and probably prevent the failure of clinical treatments. Evaluating the potential of Sanger sequencing to identify genetically resistant determinants in Helicobacter pylori clinical isolates will be important. Methods: 180 cultured strains have been tested using agar dilution for antibiotic susceptibility. NCBI BLAST was used to perform genotypic analysis on the sequencing data. Sanger sequencing was evaluated as an alternative method to detect resistant genotypes and susceptibility. Results: By the conventional E-test, resistance to levofloxacin, amoxicillin, metronidazole, and clarithromycin was 67.3%, 15.1%, 96.4%, and 25.5%, respectively. In contrast, tetracycline had no resistance. Resistance to multiple drugs was observed in 8.12% of the strains. The genetic determinants of resistance to CLA was 23s rRNA, the determinants of resistance to amoxicillin was Pbp1, the determinants of resistance to metronidazole was rdxA, and the determinants of resistance to levofloxacin were GyrA and GyrB. However, there was no association of resistance in tetracycline. Conclusion: We found increased rates of metronidazole antibiotic resistance, highlighting the necessity for alternative therapies and periodic evaluation. Sanger sequencing has proved to be highly effective and holds the potential to be implemented in policies catering to local treatments.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Amoxicillin/pharmacology , Amoxicillin/therapeutic use , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , China , Clarithromycin/pharmacology , Clarithromycin/therapeutic use , Drug Resistance, Microbial , Helicobacter Infections/drug therapy , Helicobacter Infections/genetics , Helicobacter pylori/genetics , Humans , Levofloxacin/pharmacology , Levofloxacin/therapeutic use , Metronidazole/pharmacology , Metronidazole/therapeutic use , Microbial Sensitivity Tests , Tetracycline/pharmacology , Tetracycline/therapeutic use
12.
Plant Physiol ; 188(4): 1993-2011, 2022 03 28.
Article in English | MEDLINE | ID: mdl-34963002

ABSTRACT

Lignin is a complex phenylpropanoid polymer deposited in the secondary cell walls of vascular plants. Unlike most gymnosperm and eudicot lignins that are generated via the polymerization of monolignols, grass lignins additionally incorporate the flavonoid tricin as a natural lignin monomer. The biosynthesis and functions of tricin-integrated lignin (tricin-lignin) in grass cell walls and its effects on the utility of grass biomass remain largely unknown. We herein report a comparative analysis of rice (Oryza sativa) mutants deficient in the early flavonoid biosynthetic genes encoding CHALCONE SYNTHASE (CHS), CHALCONE ISOMERASE (CHI), and CHI-LIKE (CHIL), with an emphasis on the analyses of disrupted tricin-lignin formation and the concurrent changes in lignin profiles and cell wall digestibility. All examined CHS-, CHI-, and CHIL-deficient rice mutants were largely depleted of extractable flavones, including tricin, and nearly devoid of tricin-lignin in the cell walls, supporting the crucial roles of CHS and CHI as committed enzymes and CHIL as a noncatalytic enhancer in the conserved biosynthetic pathway leading to flavone and tricin-lignin formation. In-depth cell wall structural analyses further indicated that lignin content and composition, including the monolignol-derived units, were differentially altered in the mutants. However, regardless of the extent of the lignin alterations, cell wall saccharification efficiencies of all tested rice mutants were similar to that of the wild-type controls. Together with earlier studies on other tricin-depleted grass mutant and transgenic plants, our results reflect the complexity in the metabolic consequences of tricin pathway perturbations and the relationships between lignin profiles and cell wall properties.


Subject(s)
Lignin , Oryza , Acyltransferases/metabolism , Flavonoids , Lignin/metabolism , Oryza/genetics , Oryza/metabolism
13.
Planta ; 255(1): 25, 2021 Dec 23.
Article in English | MEDLINE | ID: mdl-34940917

ABSTRACT

MAIN CONCLUSION: This study systematically identifies 112 U2A genes from 80 plant species by combinatory bioinformatics analysis, which is important for understanding their phylogenetic history, expression profiles and for predicting specific functions. In eukaryotes, a pre-mRNA can generate multiple transcripts by removing certain introns and joining corresponding exons, thus greatly expanding the transcriptome and proteome diversity. The spliceosome is a mega-Dalton ribonucleoprotein (RNP) complex that is essential for the process of splicing. In spliceosome components, the U2 small nuclear ribonucleoprotein (U2 snRNP) forms the pre-spliceosome by association with the branch site. An essential component that promotes U2 snRNP assembly, named U2A, has been extensively identified in humans, yeast and nematodes. However, studies examining U2A genes in plants are scarce. In this study, we performed a comprehensive analysis and identified a total of 112 U2A genes from 80 plant species representing dicots, monocots, mosses and algae. Comparisons of the gene structures, protein domains, and expression patterns of 112 U2A genes indicated that the conserved functions were likely retained by plant U2A genes and important for responses to internal and external stimuli. In addition, analysis of alternative transcripts and splice sites of U2A genes indicated that the fifth intron contained a conserved alternative splicing event that might be important for its molecular function. Our work provides a general understanding of this splicing factor family in terms of genes and proteins, and it will serve as a fundamental resource that will contribute to further mechanistic characterization in plants.


Subject(s)
Plants/genetics , Ribonucleoprotein, U2 Small Nuclear , Spliceosomes , Phylogeny , RNA Splicing/genetics , RNA Splicing Factors/metabolism , Ribonucleoprotein, U2 Small Nuclear/genetics , Ribonucleoprotein, U2 Small Nuclear/metabolism , Spliceosomes/genetics , Spliceosomes/metabolism
14.
Front Plant Sci ; 12: 747131, 2021.
Article in English | MEDLINE | ID: mdl-34925402

ABSTRACT

Lycoris sprengeri (L. sprengeri) is an important ornamental bulbous plant, and its numerous varieties in different color forms are widely planted. Multiple color types of petals in L. sprengeri provide us with possibilities to delineate the complicated metabolic networks underlying the biochemical traits behind color formation in this plant species, especially petal color. In this study, we sequenced and annotated a reference transcriptome of pink and white petals of L. sprengeri and analyzed the metabolic role of anthocyanin biosynthesis in regulating color pigment metabolism. Briefly, white and pink petal samples were sequenced with an Illumina platform, to obtain the reads that could be assembled into 100,778 unique sequences. Sequences expressed differentially between white vs. pink petals were further annotated with the terms of Gene Ontology (GO), Clusters of Orthologous Groups (COG), Kyoto Encyclopedia of Genes and Genomes (KEGG), and eggNOG. Gene expression analyses revealed the repression of anthocyanin and steroid biosynthesis enzymes and R2R3 MYB transcription factor (TF) genes in white petals compared to pink petals. Furthermore, the targeted metabolic profiling of anthocyanins revealed that color-related delphinidin (Del) and cyanidin (Cy) pigments are lower in white petals, which correlate well with the reduced gene expression levels of anthocyanin biosynthesis genes. Taken together, it is hypothesized that anthocyanin biosynthesis, steroid biosynthesis, and R2R3 MYB TFs may play vital regulatory roles in petal color development in L. sprengeri. This work provides a valuable genomic resource for flower breeding and metabolic engineering in horticulture and markers for studying the flower trait evolution of L. sprengeri.

15.
J Healthc Eng ; 2021: 5031667, 2021.
Article in English | MEDLINE | ID: mdl-34804452

ABSTRACT

Objective: To explore the correlation between the resistance characteristics of Helicobacter pylori (HP) and antibiotic use density (AUD) in a hospital from 2012 to 2018. Methods: HP strains isolated from Chinese PLA General Hospital from 2012 to 2018 were collected to analyze the drug resistance of clarithromycin, levofloxacin, amoxicillin, and metronidazole, and their correlation with the AUD of the outpatient department and inpatient department was analyzed, respectively. Results: From 2012 to 2018, metronidazole-resistant strains accounted for the largest proportion, followed by clarithromycin and levofloxacin, and amoxicillin-resistant strains accounted for the least. In 2012-2018, the resistance rate of clarithromycin, levofloxacin, amoxicillin, and metronidazole has basically increased year by year; from 2012 to 2018, the highest outpatient AUD in a hospital was amoxicillin, followed by clarithromycin and levofloxacin, metronidazole was the lowest, and the inpatient AUD from high to low was levofloxacin, metronidazole, amoxicillin, and clarithromycin. The drug resistance rate of HP in the hospital from 2012 to 2018 was positively correlated with the AUD of clarithromycin (r = 0.884, P=0.017) and levofloxacin (r = 0.934, P=0.002) in the outpatient department. Conclusions: Helicobacter pylori has the strongest resistance to metronidazole and the worst resistance to amoxicillin in the hospital from 2012 to 2018, being related to the intensity of clarithromycin and levofloxacin in the outpatient department. It may provide certain reference significance for the clinical treatment of Helicobacter pylori.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Anti-Bacterial Agents/therapeutic use , Drug Resistance, Multiple, Bacterial , Helicobacter Infections/drug therapy , Hospitals , Humans
16.
Front Plant Sci ; 12: 733198, 2021.
Article in English | MEDLINE | ID: mdl-34512707

ABSTRACT

Tricin (3',5'-dimethoxyflavone) is a specialized metabolite which not only confers stress tolerance and involves in defense responses in plants but also represents a promising nutraceutical. Tricin-type metabolites are widely present as soluble tricin O-glycosides and tricin-oligolignols in all grass species examined, but only show patchy occurrences in unrelated lineages in dicots. More strikingly, tricin is a lignin monomer in grasses and several other angiosperm species, representing one of the "non-monolignol" lignin monomers identified in nature. The unique biological functions of tricin especially as a lignin monomer have driven the identification and characterization of tricin biosynthetic enzymes in the past decade. This review summarizes the current understanding of tricin biosynthetic pathway in grasses and tricin-accumulating dicots. The characterized and potential enzymes involved in tricin biosynthesis are highlighted along with discussion on the debatable and uncharacterized steps. Finally, current developments of bioengineering on manipulating tricin biosynthesis toward the generation of functional food as well as modifications of lignin for improving biorefinery applications are summarized.

17.
Environ Sci Technol ; 55(19): 12951-12960, 2021 10 05.
Article in English | MEDLINE | ID: mdl-34524792

ABSTRACT

Plastic pollution is fast becoming one of the most pressing global issues that we currently face. Remote areas, such as the polar regions and the Tibetan Plateau, are now also exposed to microplastic contamination. However, with the impact of global warming, the transport of microplastics within the glacier-lake basins in such regions remains unclear. In this work, the Nam Co Basin in the Tibetan Plateau was selected to study the characteristics of microplastics in the rain fallout, lake water, glacial runoff, and non-glacial runoff. Fiber and films were the most common microplastic morphologies in all water samples; a higher proportion (37%) of light-weighing polypropylene and small-size (50-300 µm, ∼30%) microplastics were found in the glacial runoff. Air mass trajectory analysis showed that microplastics could be transported through the atmosphere over a distance of up to 800 km. For microplastic loading in lakes, the atmospheric fallout was estimated to be 3.3 tons during the monsoon season, whereas the contributions of glacial runoff (∼41 kg) and non-glacial runoff (∼522 kg) were relatively low. For the microplastic loading in glaciers, the atmospheric deposition was ∼500 kg/yr, and the output caused by glacial melting only accounted 8% of the total atmospheric input. All these results suggested that the dominant pathway through which microplastics enter remote mountainous lake basins is atmospheric deposition, and once deposited on glaciers, microplastics will be stored for a long time. This work provides quantitative evidence elucidating the fate of microplastics in alpine lake environments.


Subject(s)
Microplastics , Water Pollutants, Chemical , Environmental Monitoring , Lakes , Plastics , Tibet , Water Pollutants, Chemical/analysis
18.
Article in English | MEDLINE | ID: mdl-34462642

ABSTRACT

Panax notoginseng saponins (PNS), the main bioactive constituents of a traditional Chinese herb Panax notoginseng, were commonly used for ischemic stroke in China. However, the associated cellular and molecular mechanisms of PNS have not been well examined. This study aimed to decipher the underlying molecular target of PNS in the treatment of cerebral ischemia. The oxygen-glucose-deprived (OGD) model of rat brain microvascular endothelial cells (BMECs) was used in this study. The alteration of gene expression in rat BMECs after PNS treatment was measured by microarray and indicated that there were 38 signaling pathways regulated by PNS. Among them, RIG-I receptor and related signaling molecules TNF receptor-associated factor 2 (Traf2) and nuclear factor-kappa B (NF-κB) were significantly suppressed by PNS, which was verified again in OGD-induced BMECs measured by FQ-PCR and western blotting and in middle cerebral artery occlusion (MCAO) rats measured by immunohistochemistry. The levels of TNF-α, IL-8, and the downstream cytokines regulated by RIG-I receptor pathway were also decreased by PNS. Meanwhile, the neurological evaluation, hematoxylin and eosin (HE) staining, and Evans blue staining were conducted to evaluate the effect of PNS in MCAO rats. Results showed PNS significantly improved functional outcome and cerebral vascular leakage. Flow cytometry showed the number of the inflammatory cells infiltrated in brain tissue was decreased in PNS treatment. Our results identified that RIG-I signaling pathway mediated anti-inflammatory properties of PNS in cerebral ischemia, which provided the novel insights of PNS application in clinics.

19.
Food Funct ; 12(13): 5892-5902, 2021 Jul 05.
Article in English | MEDLINE | ID: mdl-34019608

ABSTRACT

Hepatocyte apoptosis is involved in the pathogenesis of alcohol-associated liver disease (ALD) and anti-apoptotic agents/extracts are thereby of great importance in the prevention/treatment of ALD. In this study, the protective effects of 10 edible flowers against ethanol-induced cell death were investigated in HepG2 cells, with rose (Rosa rugosa) showing the strongest activity. Therefore, rose was chosen for further separation and purification of bioactive fractions. A special fraction, SLs, was found to significantly increase the viability of EtOH-treated cells and attenuated EtOH-induced apoptosis partially via the activation of the AMPK/SIRT1 signaling pathway. Chromatographic analysis identified a series of hydroxycinnamic acid amides, kaempferol glycosides, and quercetin glycosides in this fraction, while the following intracellular uptake and cytotoxicity studies revealed that N1,N5,N10-(E)-tri-p-coumaroylspermidine (a hydroxycinnamic acid amide) in this fraction exhibited remarkable hepatoprotective activity with similar effective dosage to sulforaphane. Hence, our results highlighted the anti-alcohol and hepatoprotective benefits of consuming rose.


Subject(s)
Apoptosis/drug effects , Ethanol/adverse effects , Plant Extracts/pharmacology , Rosa/chemistry , Cell Death/drug effects , Coumaric Acids/pharmacology , Flowers/chemistry , Hep G2 Cells , Humans , Liver Diseases, Alcoholic , Signal Transduction/drug effects , Sirtuin 1/metabolism
20.
J Exp Bot ; 71(16): 4715-4728, 2020 08 06.
Article in English | MEDLINE | ID: mdl-32386058

ABSTRACT

Flavonoids are essential for male fertility in some but not all plant species. In rice (Oryza sativa), the chalcone synthase mutant oschs1 produces flavonoid-depleted pollen and is male sterile. The mutant pollen grains are viable with normal structure, but they display reduced germination rate and pollen-tube length. Analysis of oschs1/+ heterozygous lines shows that pollen flavonoid deposition is a paternal effect and fertility is independent of the haploid genotypes (OsCHS1 or oschs1). To understand which classes of flavonoids are involved in male fertility, we conducted detailed analysis of rice mutants for branch-point enzymes of the downstream flavonoid pathways, including flavanone 3-hydroxylase (OsF3H; flavonol pathway entry enzyme), flavone synthase II (CYP93G1; flavone pathway entry enzyme), and flavanone 2-hydroxylase (CYP93G2; flavone C-glycoside pathway entry enzyme). Rice osf3h and cyp93g1 cyp93g2 CRISPR/Cas9 mutants, and cyp93g1 and cyp93g2 T-DNA insertion mutants showed altered flavonoid profiles in anthers, but only the osf3h and cyp93g1 cyp93g2 mutants displayed reduction in seed yield. Our findings indicate that flavonoids are essential for complete male fertility in rice and a combination of different classes (flavanones, flavonols, flavones, and flavone C-glycosides) appears to be important, as opposed to the essential role played primarily by flavonols that has been previously reported in several plant species.


Subject(s)
Oryza , Fertility , Flavonoids , Flavonols , Oryza/genetics , Seeds
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