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1.
Acta Biomater ; 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39168421

ABSTRACT

The synergy between chemodynamic therapy (CDT) and photothermal therapy (PTT) offers a promising antimicrobial strategy for periodontitis, yet faces challenges like complex material structure and limited NIR-I light penetration. Additionally, low endogenous H2O2 levels in biofilm and a focus on bacterial eradication over colonization prevention limit current treatments. To address these issues, we newly introduce a single-material system (Cu3P@PAH@Lox) that integrates dual functionalities to synergistically enhance antimicrobial effects and significantly reduce pathogen co-aggregation. This system utilizes PTT to increase local temperature, boosting •OH production in CDT while downregulating heat shock proteins to enhance PTT efficacy, forming a self-reinforcing feedback loop. Lactate oxidase (Lox) is employed to convert lactate-a metabolite in periodontal biofilm-into H2O2, further amplifying CDT's potential. In vitro Cu3P@PAH@Lox demonstrates a remarkable synergistic effect against dual-species biofilms by more than 2-log reduction of colony-forming unit. Moreover, Cu3P@PAH@Lox exhibits outstanding synergistic antibacterial performances to alleviate inflammation and destruction of tissue in vivo periodontitis model. Furthermore, the mechanism of pathogen co-aggregation disruption by PTT is verified via the Cbe-Ltp1-Ptk1-fimA signaling pathway. This single-material multimodal system we have herein demonstrated for the first time marks a significant advancement in periodontitis treatment, eradicating microbes and preventing bacterial colonization, offering a path to comprehensive periodontal care. STATEMENT OF SIGNIFICANCE: The synergy between chemodynamic therapy (CDT) and photothermal therapy (PTT) has been considered a promising therapy for periodontitis. Yet, facing challenges, the complex material structure, limited NIR-I light penetration, low endogenous H2O2 level in biofilm, and a focus on bacterial eradication over colonization prevention are still insufficient. This study pioneers a unique, single-material system (Cu3P@PAH@Lox) that synergistically enhances antimicrobial effects and substantially curtails pathogen co-aggregation, advancing periodontitis therapy. By exploiting PTT to elevate local temperatures, thereby increasing hydroxyl radical production in CDT and concurrently suppressing heat shock proteins, the system establishes a potent, self-enhancing loop. Furthermore, lactate oxidase is innovatively utilized to convert lactate from periodontal biofilm into hydrogen peroxide, augmenting the efficacy of CDT. The introduction of Cu3P@PAH@Lox is poised to revolutionize periodontitis treatment, eliminating microbes and impeding bacterial colonization, thereby charting a course for comprehensive periodontal management.

2.
Food Chem ; 460(Pt 2): 140687, 2024 Dec 01.
Article in English | MEDLINE | ID: mdl-39106813

ABSTRACT

The synergistic effects of plasma-activated water (PAW) and twin-screw extrusion (TSE) on the structural, physicochemical, antioxidant, and digestive properties of yam flour (YF) were studied. Compared to common TSE, PAW-TSE reduced the protein, starch, and polyphenol contents, swelling power, and gel property of YF, while PAW-TSE enhanced the flavonoid content, whiteness index, solubility, and antioxidant property of YF. Moreover, the results of structural characterization and differential scanning calorimetry indicated that the long-range or short-range ordering, and gelatinization enthalpy of starch in YF were reduced after PAW-TSE, while the structure ordering of proteins in YF increased. Furthermore, the in vitro digestibility results demonstrated a reduction in the rate of enzymatic hydrolysis, coupled with an increase in total contents of slowly digestible and resistant starch after PAW-TSE. It should be noted that TSE using PAW prepared by a longer plasma treatment resulted in a more significant improvement effect on YF.


Subject(s)
Antioxidants , Digestion , Dioscorea , Flour , Solubility , Starch , Water , Antioxidants/chemistry , Dioscorea/chemistry , Flour/analysis , Water/chemistry , Starch/chemistry , Starch/metabolism , Food Handling
3.
Genes (Basel) ; 15(7)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-39062618

ABSTRACT

Cephaleuros species are well-known as plant pathogens that cause red rust or algae spot diseases in many economically cultivated plants that grow in shady and humid environments. Despite their prevalence, the adaptive evolution of these pathogens remains poorly understood. We sequenced and characterized three Cephaleuros (Cephaleuros lagerheimii, Cephaleuros diffusus, and Cephaleuros virescens) chloroplast genomes, and compared them with seven previously reported chloroplast genomes. The chloroplast sequences of C. lagerheimii, C. diffusus, and C. virescens were 480,613 bp, 383,846 bp, and 472,444 bp in length, respectively. These chloroplast genomes encoded 94 genes, including 27 tRNA genes, 3 rRNA genes, and 64 protein-coding genes. Comparative analysis uncovered that the variation in genome size was principally due to the length of intergenic spacer sequences, followed by introns. Furthermore, several highly variable regions (trnY-GTA, trnL-TAG, petA, psbT, trnD-GTC, trnL-TAA, ccsA, petG, psaA, psaB, rps11, rps2, and rps14) were identified. Codon bias analysis revealed that the codon usage pattern of Cephaleuros is predominantly shaped by natural selection. Additionally, six chloroplast protein-coding genes (atpF, chlN, psaA, psaB, psbA, and rbcL) were determined to be under positive selection, suggesting they may play a vital roles in the adaptation of Cephaleuros to low-light intensity habitats.


Subject(s)
Evolution, Molecular , Genome, Chloroplast , Phylogeny , Chloroplasts/genetics , Codon Usage
4.
BMC Nurs ; 23(1): 404, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886795

ABSTRACT

BACKGROUND: As indispensable reserves for the nursing workforce, undergraduate nursing students must possess self-directed learning abilities to consistently update their professional knowledge and adapt to the evolving demands of professional development. The acquisition of self-directed learning abilities can help undergraduate nursing students augment their theoretical knowledge and refine their clinical practice skills, thus fulfilling the demand from patients for high-quality nursing services. Hence, comprehending and investigating the factors that influence the development of self-directed learning abilities in nursing students is of paramount importance for nursing education and advancement of the nursing profession. OBJECTIVES: This study investigated the status of and associations between perceived stress, psychological capital, and self-directed learning abilities among undergraduate nursing students. Additionally, it examines the mediating role of psychological capital in the relationship between perceived stress and self-directed learning abilities. Thus, aiming to provide nursing educators with new directions for enhancing self-directed learning abilities. DESIGN: A cross-sectional descriptive study. METHODS: In February and March 2023, 900 undergraduate nursing students from 10 nursing schools completed an online questionnaire. The questionnaire included measures of perceived stress, psychological capital, and self-directed learning ability. Data were analyzed using SPSS 27.0 and the PROCESS macro tool. RESULTS: The scores for perceived stress, psychological capital, and self-directed learning ability among undergraduate nursing students were 40.07 ± 5.90, 99.89 ± 16.59, and 87.12 ± 9.20, respectively. Self-directed learning abilities were negatively correlated with perceived stress (r = -0.415, p < 0.001) and positively correlated with psychological capital (r = 0.465, p < 0.001). Perceived stress was negatively correlated with psychological capital (r = -0.630, p < 0.001). Psychological capital partially mediated the relationship between perceived stress and self-directed learning abilities among undergraduate nursing students, with a mediation effect of -0.166, accounting for 49.55% of the total effect. CONCLUSION: This study found that undergraduate nursing students perceived high levels of stress, possessed low levels of psychological capital, and had moderate levels of self-directed learning. Perceived stress and psychological capital directly influenced undergraduate nursing students' self-directed learning abilities, and perceived stress indirectly affected self-directed learning abilities through psychological capital. Nursing managers and educators should alleviate the perceived stress of undergraduate nursing students and cultivate their positive psychological capital to enhance self-directed learning abilities.

5.
BMC Genomics ; 25(1): 561, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38840044

ABSTRACT

BACKGROUND: Artemisia selengensis, classified within the genus Artemisia of the Asteraceae family, is a perennial herb recognized for its dual utility in culinary and medicinal domains. There are few studies on the chloroplast genome of A. selengensis, and the phylogeographic classification is vague, which makes phylogenetic analysis and evolutionary studies very difficult. RESULTS: The chloroplast genomes of 10 A. selengensis in this study were highly conserved in terms of gene content, gene order, and gene intron number. The genome lengths ranged from 151,148 to 151,257 bp and were typical of a quadripartite structure with a total GC content of approximately 37.5%. The chloroplast genomes of all species encode 133 genes, including 88 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Due to the contraction and expansion of the inverted repeats (IR), the overlap of ycf1 and ndhF genes occurred at the inverted repeats B (IRB) and short single copy sequence (SSC) boundaries. According to a codon use study, the frequent base in the chloroplast genome of A. selengensis' third codon position was A/T. The number of SSR repeats was 42-44, most of which were single nucleotide A/T repeats. Sequence alignment analysis of the chloroplast genome showed that variable regions were mainly distributed in single copy regions, nucleotide diversity values of 0 to 0.009 were calculated by sliding window analysis, 8 mutation hotspot regions were detected, and coding regions were more conserved than non-coding regions. Analysis of non-synonymous substitution (Ka) and synonymous substitution (Ks) revealed that accD, rps12, petB, and atpF genes were affected by positive selection and no genes were affected by neutral selection. Based on the findings of the phylogenetic analysis, Artemisia selengensis was sister to the genus Artemisia Chrysanthemum and formed a monophyletic group with other Artemisia genera. CONCLUSIONS: In this research, the present study systematically compared the chloroplast genomic features of A. selengensis and provided important information for the study of the chloroplast genome of A. selengensis and the evolutionary relationships among Asteraceae species.


Subject(s)
Artemisia , Genome, Chloroplast , High-Throughput Nucleotide Sequencing , Phylogeny , Artemisia/genetics , Artemisia/classification , Base Composition , Microsatellite Repeats , Evolution, Molecular , Codon Usage
6.
Child Adolesc Psychiatry Ment Health ; 17(1): 113, 2023 Oct 04.
Article in English | MEDLINE | ID: mdl-37794411

ABSTRACT

BACKGROUND: The psychological impact of the COVID-19 pandemic has been understudied among vulnerable populations. This study aimed to examine the immediate and longer-term changes in the mental health of children with parent-child separation experiences during the COVID-19 pandemic, and identify potential buffering opportunities for mental health. METHODS: This longitudinal cohort study used data from 723 rural Chinese children who provided data before (Oct. 2019) the COVID-19 pandemic and during the following 2 years. Changes in the probability of depressive symptoms, anxiety symptoms, non-suicide self-injurious (NSSI), suicidal ideation, suicide plan, and suicide attempt were tested across four waves using generalized estimating models (GEE). RESULTS: Compared with children who never experienced parent-child separation, children persistently separated from parents since birth experienced greater deterioration in all mental health in the 2-year follow-up (average change: depressive symptoms: ß = 0.59, 95% CI [0.26, 0.93]; anxiety symptoms: ß = 0.45, 95% CI [0.10, 0.81]; NSSI: ß = 0.66, 95% CI [0.31, 1.01]; suicide ideation: ß = 0.67, 95% CI [0.38, 0.96]; suicide plan: ß = 0.77, 95% CI [0.38, 1.15]; suicide attempt: ß = 1.12, 95% CI [0.63, 1.62]). However, children with childhood separation from their parents but reunited with them during the transition to adolescence showed similar even lower changes to counterparts who never experienced parent-child separation (all ps > 0.05). CONCLUSION: These results indicating improvements in supportiveness of the caregiving environment during the transition to adolescence may provide the opportunity to buffer the adverse impact of COVID-19 on mental health. Translating such knowledge to inform intervention and prevention strategies for youths exposed to adversity is a critical goal for the field.

7.
Polymers (Basel) ; 15(18)2023 Sep 07.
Article in English | MEDLINE | ID: mdl-37765535

ABSTRACT

Thermoplastic poly(ether/ester) elastomer (TPEE) has great potential as a mattress material due to its high resilience, breathability, and light weight. This study aimed to evaluate the feasibility of TPEE-3D fibrous material (T3DF), a three-dimensional block material made of TPEE fibers randomly aligned and loop-connected, for mattress application. After testing the compression properties of T3DF, the effects of T3DF structural layers on mattress firmness were investigated. The results showed that T3DF had good energy absorption capacity, broad indentation hardness range (126.94-333.82 N), and high compression deflection coefficient (2.79-4.39). The thickness and density of T3DF were the main factors influencing mattress firmness, and the impact of thickness was more significant (p < 0.05). Owing to the hard and soft segments contained in TPEE, T3DF could be used for both the padding and core layers of the mattress. The hardness value and Dsurface of the mattress with a T3DF padding layer increased with T3DF density but decreased with T3DF thickness. Moreover, the hardness value and Dsurface of the mattress with a T3DF core layer increased with T3DF density, while with T3DF thickness, its Dsurface increased and Dbottom decreased. Therefore, the thick and low-density T3DF padding layer could improve the comfort of the mattress surface, a thin T3DF core layer could satisfy both the softer surface and the firmer bottom of the mattress.

8.
Water Res ; 244: 120485, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37611357

ABSTRACT

The musty odorant (2-methylisoborneol, MIB) is prevalent in source water reservoirs and has become one of the major challenges for drinking water quality. This study proposes an approach to control the growth of MIB-producing cyanobacteria in a small reservoir based on hydraulic regulation, according to the results of long-term field investigations, laboratory culture experiments, model construction, and field application. Field investigations found that longer hydraulic retention time (HRT) is a factor that triggers MIB episodes. The culture study revealed that the maximum cell density, growth rate of MIB-producing Planktothricoides raciborskii, and MIB concentration are determined by the HRT (R2= 0.94, p-value < 0.001) and can be minimized by decreasing the HRT to less than 10 d. On this basis, an HRT regulation model was constructed and validated by field investigation, and critical HRT values were evaluated for 14 cyanobacteria genera. By decreasing the HRT to 5.4 ± 0.8 d, which is lower than the critical value of 7.5 ∼ 15.0 d, an MIB episode was successfully terminated in ZXD Reservoir in 2021. The results suggest that the proposed principle can provide a scientific basis for HRT regulation, which has been proved to be effective and feasible. This approach avoids negative impacts on water quality, does not require extra investment in engineering infrastructure, and in some cases may be applied readily by changing existing operational procedures. Therefore, HRT-based regulation is a promising strategy targeting MIB control and possibly for other cyanobacterial-derived water quality problems in small reservoirs.


Subject(s)
Drinking Water , Odorants/analysis , Water Quality
9.
Physiol Behav ; 270: 114305, 2023 10 15.
Article in English | MEDLINE | ID: mdl-37507079

ABSTRACT

A trend toward earlier pubertal maturation in both sexes has been shown in many countries. Early puberty affects an increasing proportion of children for reasons that remain obscure. Novel candidate biomarkers are strongly needed. We sought to apply untargeted metabolomic profiling to identify triggering mechanisms and candidate biomarkers in children with early puberty. Participants aged 7 - 12 years old were recruited directly from two elementary schools of Bengbu, Anhui Province, China, from Feb 2021 to May 2021. Early puberty was determined by breast and testicular development at baseline (May 2021) and 6-month later. Ultra-high-performance liquid chromatography-based untargeted metabolomic profiling was performed on urine samples of children with early puberty and control subjects. Metabolomic profiling for early puberty in a sex dependent manner. For boys, we identified several perturbed pathways, including histidine metabolism, glycine, serine and threonine metabolism, and selenoamino acid metabolism, associated with early puberty. In contrast, there were differences in pyruvate metabolism, one carbon pool by folate, and D-glutamine and D-glutamate metabolism pathways in girls with early puberty compared with controls. In addition, 4-hydroxyhippuric acid and 5-methoxytryptophol were shown as potential independent diagnostic biomarker for early puberty in boys, 3-hydroxybenzoic acid and glutaminylproline were shown as early biomarker for early puberty in girls, achieving area under the ROC curve of 0.71 and 0.72 in discriminating early puberty boys, and 0.70 and 0.74 in discriminating early puberty girls from controls. Through metabolomic analysis, we have identified metabolic perturbations and potential biomarkers of early puberty.


Subject(s)
Metabolomics , Puberty , Male , Female , Humans , Child , Biomarkers/urine , China , Chromatography, High Pressure Liquid
10.
Microbiol Spectr ; 11(3): e0038023, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37154757

ABSTRACT

DNA methylation is a defense that microorganisms use against extreme environmental stress, and improving resistance against environmental stress is essential for industrial actinomycetes. However, research on strain optimization utilizing DNA methylation for breakthroughs is rare. Based on DNA methylome analysis and KEGG pathway assignment in Streptomyces roseosporus, we discovered an environmental stress resistance regulator, TagR. A series of in vivo and in vitro experiments identified TagR as a negative regulator, and it is the first reported regulator of the wall teichoic acid (WTA) ABC transport system. Further study showed that TagR had a positive self-regulatory loop and m4C methylation in the promoter improved its expression. The ΔtagR mutant exhibited better hyperosmotic resistance and higher decanoic acid tolerance than the wild type, which led to a 100% increase in the yield of daptomycin. Moreover, enhancing the expression of the WTA transporter resulted in better osmotic stress resistance in Streptomyces lividans TK24, indicating the potential for wide application of the TagR-WTA transporter regulatory pathway. This research confirmed the feasibility and effectiveness of mining regulators of environmental stress resistance based on the DNA methylome, characterized the mechanism of TagR, and improved the resistance and daptomycin yield of strains. Furthermore, this research provides a new perspective on the optimization of industrial actinomycetes. IMPORTANCE This study established a novel strategy for screening regulators of environmental stress resistance based on the DNA methylome and discovered a new regulator, TagR. The TagR-WTA transporter regulatory pathway improved the resistance and antibiotic yield of strains and has the potential for wide application. Our research provides a new perspective on the optimization and reconstruction of industrial actinomycetes.


Subject(s)
Daptomycin , Streptomyces , Epigenome , Anti-Bacterial Agents , Streptomyces/genetics , Streptomyces/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism
11.
Psychoneuroendocrinology ; 152: 106101, 2023 06.
Article in English | MEDLINE | ID: mdl-37004468

ABSTRACT

CONTEXT: The mechanisms underlying the elevated long-term health risk in girls with precocious puberty remain unclear, but might result from physiological wear and tear associated with greater exposure to early life adversity. OBJECTIVE: This study aims to explore early life adversity in girls with precocious puberty and its association with allostatic load. METHODS: Early life adversity and hair cortisol concentration were measured among 213 girls with precocious puberty (8.21 ± 1.07). Allostatic load score is constructed by using 13 physiological biomarkers representing four systems and hair cortisol concentration. Multivariate linear regression models have estimated the associations between cumulative early life adversity exposure with total and system-specific allostatic load scores. Associations between cumulative early life adversity and the risk of high allostatic load (3 + high-risk biomarkers) were tested using binary logistics regression. RESULTS: More than two-thirds (67.6%) of girls with central precocious puberty reported two or more early life adversity exposure. Compared to those with no early life adversity exposure, girls who reported early life adversity score ≥ 2 had significantly higher total allostatic load score (ß: 1.20-1.64, P < 0.001). Metabolic system was more sensitive to cumulative early life adversity exposure, each form of early life adversity exposure was associated with 0.48-unit increases in metabolic allostatic load score (95%CI: 0.06, 0.90, P = 0.026). Girls reported early life adversity score ≥ 3 were three times more likely to have a high allostatic load compared with those without early life adversity exposure in both unadjusted and adjusted models (ORadjusted=3.83, 95%CI: 1.17, 12.55, P = 0.001). CONCLUSION: Multisystem physiological dysregulation is observed in girls with central precocious puberty, which might result from cumulative wear-and-tear associated with early life adversity.


Subject(s)
Allostasis , Puberty, Precocious , Female , Humans , Allostasis/physiology , Hydrocortisone/metabolism , Biomarkers , Hair/metabolism
12.
Front Pharmacol ; 14: 1094089, 2023.
Article in English | MEDLINE | ID: mdl-36923353

ABSTRACT

Background: As the coronavirus disease 2019 (COVID-19) pandemic progressed, especially with the emergence of the Omicron variant, the proportion of infected children and adolescents increased significantly. Some treatment such as Chinese herbal medicine has been administered for COVID-19 as a therapeutic option. Jin-Zhen Oral Liquid is widely used for pediatric acute bronchitis, while the efficacy and safety in the treatment of pediatric COVID-19 are unclear. Methods: We conducted a randomized controlled, open-label, multicenter, non-inferiority clinical study involving hospitalized children with mild to moderate COVID-19. Children eligible for enrollment were randomly assigned in a 1:1 ratio to Jin-Zhen Oral Liquid (the treatment group) and Jinhua Qinggan Granules (the positive control group) and received the respective agent for 14 days, followed by a 14-day follow-up after discontinuation of the treatment. The primary efficacy endpoint was the time to first negative viral testing. The secondary endpoints were the time and rate of major symptoms disappearance, duration of hospitalization, and the proportion of symptoms changed from asymptomatic or mild to moderate or severe/critical illness. In addition, the safety end points of any adverse events were observed. Results: A total of 240 child patients were assigned randomly into the Jin-Zhen Oral Liquid (117 patients) and Jinhua Qinggan Granules (123 patients) groups. There was no significant difference of the baselines in terms of the clinical characteristics and initial symptoms between the two groups. After 14-day administration, the time to first negative viral testing in the Jin-Zhen group (median 6.0 days, 95% CI 5.0-6.0) was significantly shorter compared with the positive control Jinhua Qinggan Granules group (median 7.0 days, 95% CI 7.0-8.0). The time and rate of major clinical symptoms disappearance were comparable to the positive control. The symptom disappearance time of pharyngalgia and hospitalization duration were significantly shortened in the Jin-zhen Oral Liquid group. No participants in either group experienced post-treatment exacerbation to severe or critical illness. No adverse events were observed in the Jin-Zhen Oral Liquid treatment group (0.0%) while 1 patient with adverse events occurred in the positive control Jinhua Qinggan granules group (0.8%). No serious adverse events were observed during the study period in both groups. Conclusion: Jin-Zhen Oral Liquid is safe and effective in the treatment of mild to medium COVID-19 in children. It is non-inferior to Jinhua Qinggan granules in shortening the time to first negative viral testing, the time and rate of major clinical symptoms disappearance, and the hospitalization duration. The results suggest that Jin-Zhen Oral Liquid can be a recommended drug for treatment of pediatric COVID-19 patients.

13.
Water Res ; 231: 119667, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36724724

ABSTRACT

Cellular 2-methylisoborneol (MIB) yield of cyanobacteria varies under different conditions according to culture studies and field investigations, the causal mechanism remains unclear and results in ineffective MIB prediction. Through an intensive field survey during an MIB episode produced by Pseudanabaena cinerea in QCS reservoir, we demonstrated that MIB synthesis (mic) gene abundance (DNA) and expression (RNA) might be useful as parameters for early warning of MIB production. It was found that the abundance of mic DNA and RNA peaked ahead of MIB concentrations by 10 and 7 days, respectively. In addition, the RNA abundance (R2 = 0.45, p < 0.01) showed a slightly higher correlation with MIB compared to DNA abundance (R2 = 0.37, p < 0.01), suggesting that the conditions for the growth of Pseudanabaena cinerea might be slightly different from those for mic gene expression, which was verified by a culture experiment. The highest cell growth was obtained under 36 µmol photons m-2 s-1, while the highest cellular MIB yield and mic gene expression level were obtained under 85 µmol photons m-2 s-1. Our results clearly supported that light intensity was the virtual regulator governing the mic gene expression within the controlled culture experiment and the actual MIB episode in the reservoir. Besides these results, we developed an early warning model using mic gene abundance as an indicator of MIB episodes, which was verified in two other reservoirs. Our findings highlight the effect of light intensity on mic gene expression and MIB synthesis and provide an early warning tool targeting MIB episode prediction, which therefore should be of importance for source water authorities.


Subject(s)
Cyanobacteria , Drinking Water , Drinking Water/microbiology , Camphanes , Cyanobacteria/metabolism , Water Supply , Odorants/analysis
14.
Prog Neurobiol ; 222: 102404, 2023 03.
Article in English | MEDLINE | ID: mdl-36642095

ABSTRACT

AMPAR-lacking silent synapses are prevailed and essential for synaptic refinement and synaptic plasticity in developing brains. In mature brain, they are sparse but could be induced under several pathological conditions. How they are regulated molecularly is far from clear. miR-34a is a highly conserved and brain-enriched microRNA with age-dependent upregulated expression profile. Its neuronal function in mature brain remains to be revealed. Here by analyzing synaptic properties of the heterozygous miR-34a knock out mice (34a_ht), we have discovered that mature but not juvenile 34a_ht mice have more silent synapses in the hippocampus accompanied with enhanced synaptic NMDAR but not AMPAR function and increased spine density. As a result, 34a_ht mice display enhanced long-term potentiation (LTP) in the Schaffer collateral synapses and better spatial learning and memory. We further found that Creb1 is a direct target of miR-34a, whose upregulation and activation may mediate the silent synapse increment in 34a_ht mice. Hence, we reveal a novel physiological role of miR-34a in mature brains and provide a molecular mechanism underlying silent synapse regulation.


Subject(s)
MicroRNAs , Neuronal Plasticity , Mice , Animals , Neuronal Plasticity/physiology , Long-Term Potentiation/physiology , Hippocampus/metabolism , Synapses/metabolism , MicroRNAs/metabolism , Mice, Knockout
15.
Environ Res ; 221: 115260, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36649844

ABSTRACT

Cyanobacteria can sense different light color by adjusting the components of photosynthetic pigments including chlorophyll a (Chl a), phycoerythrin (PE), and phycocyanin (PC), etc. Filamentous cyanobacteria are the main producer of 2-methylisoborneol (MIB) and many can increase their PE levels so that they are more competitive in subsurface layer where green light is more abundant, and have caused extensive odor problems in drinking water reservoirs. Here, we identified the potential correlation between MIB biosynthesis and ambient light color induced chromatic acclimation (CA) of a MIB-producing Pseudanabaena strain. The results suggest Pseudanabaena regulates the pigment proportion through Type III CA (CA3), by increasing PE abundance and decreasing PC in green light. The biosynthesis of MIB and Chl a share the common precursor, and are positively correlated with statistical significance regardless of light color (R2=0.68; p<0.001). Besides, the PE abundance is also positively correlated with Chl a in green light (R2=0.57; p=0.019) since PE is the antenna that can only transfer the energy to PC and Chl a. In addition, significantly higher MIB production was observed in green light since more Chl a was synthesized.


Subject(s)
Cyanobacteria , Chlorophyll A , Cyanobacteria/physiology , Phycoerythrin , Phycocyanin , Acclimatization
16.
EMBO J ; 42(3): e111304, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36477886

ABSTRACT

Parvalbumin-positive neurons (PVs) are the main class of inhibitory neurons in the mammalian central nervous system. By examining diurnal changes in synaptic and neuronal activity of PVs in the supragranular layer of the mouse primary visual cortex (V1), we found that both PV input and output are modulated in a time- and sleep-dependent manner throughout the 24-h day. We first show that PV-evoked inhibition is stronger by the end of the light cycle (ZT12) relative to the end of the dark cycle (ZT0), which is in line with the lower inhibitory input of PV neurons at ZT12 than at ZT0. Interestingly, PV inhibitory and excitatory synaptic transmission slowly oscillate in opposite directions during the light/dark cycle. Although excitatory synapses are predominantly regulated by experience, inhibitory synapses are regulated by sleep, via acetylcholine activating M1 receptors. Consistent with synaptic regulation of PVs, we further show in vivo that spontaneous PV activity displays daily rhythm mainly determined by visual experience, which negatively correlates with the activity cycle of surrounding pyramidal neurons and the dorsal lateral geniculate nucleus-evoked responses in V1. These findings underscore the physiological significance of PV's daily modulation.


Subject(s)
Neurons , Parvalbumins , Animals , Mice , Parvalbumins/metabolism , Neurons/metabolism , Pyramidal Cells/metabolism , Synaptic Transmission , Sleep , Mammals
17.
Ergonomics ; 66(10): 1477-1493, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36437772

ABSTRACT

Knowledge of the parameters of the human spine is essential in designing ergonomic furniture. The purpose of this study was to evaluate spinal alignment in adolescents of various ages. The lengths, curvatures, and concave-convex spacings of the spine were investigated in 268 participants aged 9-18 years. Ten ages were classified, and the rate of increase of parameters was calculated for each age and age group. The results showed that spinal parameters, except for cervical lordosis, increased with age. Adolescents were classified as 9-10, 11-12, 13-15, and 16-18 years old. A rapid increment of lengths and concave-convex spacings occurred at ages 13-15, while that of curvatures occurred at ages 16-18. Spinal parameters differed significantly among the age groups (p < 0.05). Concave-convex spacings reflected differences in the spine more clearly than the other parameters. This study suggests the necessity of designing spine-related furniture based on spinal parameters, thus providing adaptive support for the adolescent spine, particularly the lumbar spine. Practitioner summary: This study examined spinal lengths, curvatures, and concave-convex spacings in adolescents aged 9-8 years and then divided them into four age groups. Concave-convex spacings effectively reflected spinal differences between age groups, particularly the lumbar spine. These results can inform the ergonomic design of spine-related furniture.HIGHLIGHTSSpinal parameters increased progressively between 9 and 18 years. Regression analysis showed good linear correlations between TK, LL, SK, TS, and LS with age.Age classification of adolescents was Group I (9-10 years), Group II (11-12 years), Group III (13-15 years), and Group IV (16-18 years). The rapid increment of lengths and concave-convex spacings were in Group III while that of curvatures were in Group IV.Concave-convex spacings were vital parameters to evaluate the global balance of the spine.The lumbar spine is an essential segment for characterizing spinal alignment.


Subject(s)
Lordosis , Scoliosis , Adolescent , Humans , Interior Design and Furnishings , Spine , Lumbar Vertebrae
18.
Chemosphere ; 311(Pt 1): 137007, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36330982

ABSTRACT

Up to 95% of hormones are excreted into domestic wastewater with urine or feces, but their macromolecules are difficult to biodegrade. This project studies the treatment of Ethinyl Estradiol (EE2) in swine wastewater in an Upstream Solids Reactor (USR), and explores a new method for oriented bio-feeding to regulate the anaerobic biodegradation process. It was found that the metabolism of lactic acid and propionic acid was accompanied by changes in EE2 content, but lactic acid molecules were not readily bioavailable, so adding propionic acid was more suitable. However, controlling the pH to lower (4.73) and higher (8.73) values inhibited further fermentation of acetic acid and propionic acid, which was not favorable for the removal of EE2. This is simply due to the fact that propionic acid as a carbon source changes the preference of the microbes for consuming EE2. The order of the effect of addition of propionic acid on the removal of EE2 was as follows: P400>P800>P0>P200 (addition of propionic acid). The P400 removal efficiency increased from 60% to 85%. In the metabolism of EE2, after oxidation, hydrolysis, ketosis, hydroxylation and enzymatic action, dienoic acid and oleic acid were generated, and there was no secondary pollution from EE2 metabolites. In conclusion, feeding microorganisms with propionic acid can enhance the anaerobic biodegradation of EE2, providing a new strategy for the anaerobic biodegradation and bioremediation of refractory pollutants.


Subject(s)
Ethinyl Estradiol , Wastewater , Animals , Swine , Ethinyl Estradiol/metabolism , Biodegradation, Environmental , Anaerobiosis , Lactic Acid , Estradiol/metabolism
19.
Synth Syst Biotechnol ; 7(4): 1013-1023, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35801092

ABSTRACT

Despite numerous studies on transcriptional level regulation by single genes in drug producing Actinomyces, the global regulation based on epigenetic modification is not well explored. N4-methylcytosine (m4C), an abundant epigenetic marker in Actinomycetes' genome, but its regulatory mechanism remains unclear. In this study, we identify a m4C methyltransferase (SroLm3) in Streptomyces roseosporus L30 and multi-omics studies were performed and revealed SroLm3 as a global regulator of secondary metabolism. Notably, three BGCs in ΔsroLm3 strain exhibited decreased expression compared to wild type. In-frame deletion of sroLm3 in S.roseosporus L30 further revealed its role in enhancing daptomycin production. In summary, we characterized a m4C methyltransferase, revealed the function of m4C in secondary metabolism regulation and biosynthesis of red pigment, and mapped a series of novel regulators for daptomycin biosynthesis dominated by m4C methylation. Our research further indicated that m4C DNA methylation may contribute to a metabolic switch from primary to secondary metabolism in Actinomyces.

20.
Huan Jing Ke Xue ; 43(7): 3543-3551, 2022 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-35791538

ABSTRACT

Taking the Xiaojiang and Xiangxi Rivers, two typical tributaries of the Three Gorges Reservoir, as examples, this study analyzed and compared the hydrodynamic, thermal stratification, and temporal and spatial differences in dissolved oxygen (DO) and their responses to the water storage process in the two tributaries through field monitoring at different stages of the 2020 impoundment period. The results showed that:① at the initial stage of water storage, the DO in the surface layer of the Xiaojiang River was higher (7.00-13.00 mg·L-1) due to atmospheric reoxygenation and phytoplankton photosynthesis, and the oxycline appeared in the water depth of 3-5 m. A large area of anoxia (DO<2.00 mg·L-1) or even an anaerobic sublayer occurred in the water below 5 m. The DO in the Xiangxi River could be divided into three layers vertically:oxygen-rich surface water (8.00-12.00 mg·L-1), middle water (6.00-8.00 mg·L-1), and low-oxygen bottom water (4.00-6.00 mg·L-1). ② Thermal stratification provided a stable physical environment, whereas the upstream inflow and vegetation decomposition in the water-level fluctuation zone increased the content of organic matter, which likely increased the oxygen consumption which was conducive to the formation of an anaerobic bottom layer. In the Xiangxi River, the risk of hypoxia in the bottom water body was low because of the oxygen replenishment from the long-term downslope-bottom density current.③ Continuous monitoring also showed that the storage of the reservoir played a significant role in the replenishment of DO in tributaries, which effectively and rapidly improved the anaerobic phenomenon in the Xiaojiang River. In the Three Gorges Reservoir, it is feasible to ameliorate the water ecological problems such as anoxia and anaerobic conditions in the tributaries via reservoir operation. This study aids understanding of the characteristics and differences of DO stratification in different tributaries of the Three Gorges Reservoir, which can provide theoretical and technical support for reservoir ecological operation.


Subject(s)
Environmental Monitoring , Oxygen , Humans , Hypoxia , Rivers , Water
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