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1.
Clin Nutr ; 43(8): 1812-1813, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38955056
2.
AAPS J ; 26(4): 76, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955873

RESUMO

The selection of skin is crucial for the in vitro permeation test (IVPT). The purpose of this study was to investigate the influence of different freezing-thawing processes on the barrier function of skin and the transdermal permeability of granisetron and lidocaine. Rat and hairless mouse skins were thawed at three different conditions after being frozen at -20℃ for 9 days: thawed at 4℃, room temperature (RT), and 32℃. There were no significant differences in the steady-state fluxes of drugs between fresh and thawed samples, but compared with fresh skin there were significant differences in lag time for the permeation of granisetron in rat skins thawed at RT and 32℃. Histological research and scanning electron microscopy images showed no obvious structural damage on frozen/thawed skin, while immunohistochemical staining and enzyme-linked immunosorbent assay for the tight junction (TJ) protein Cldn-1 showed significantly impaired epidermal barrier. It was concluded that the freezing-thawing process increases the diffusion rate of hydrophilic drugs partly due to the functional degradation of TJs. It's recommended that hairless, inbred strains and identical animal donors should be used, and the selected thawing method of skin should be validated prior to IVPT, especially for hydrophilic drugs.


Assuntos
Congelamento , Camundongos Pelados , Permeabilidade , Absorção Cutânea , Pele , Animais , Pele/metabolismo , Camundongos , Absorção Cutânea/efeitos dos fármacos , Ratos , Masculino , Administração Cutânea , Lidocaína/administração & dosagem , Lidocaína/farmacocinética , Ratos Sprague-Dawley
3.
Aging Ment Health ; : 1-12, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38952191

RESUMO

OBJECTIVES: To determine a pooled prevalence of depression and its influencing factors among nursing home residents. METHOD: PsycINFO, PubMed, Embase, and Web of Science were searched for studies investigating the prevalence and risk factors of late-life depression among nursing home residents between January 2012 and November 2022. Two reviewers independently completed the literature screening, data extraction and quality assessment. A random-effects model was utilized to pool the prevalence of depression and summarize the influencing factors. RESULTS: This meta-analysis included 48 studies involving 28,501 participants. The pooled prevalence of depressive mood and major depressive disorder was 53% and 27%, respectively. The rate of depressive mood is higher in lower-middle-income countries (60.0%), compared with high- (53.0%) and upper-middle-income countries (44.0%). The rate of depressive mood (35.0%) is higher among females than male (19.0%). Depression was influenced by factors, including male (OR = 0.28), insufficient income (OR = 3.53), comorbidities (OR = 2.66), pain (OR = 2.67; r = 0.31), functional disability (r = 0.33), loneliness (r = 0.43), number of chronic health problems (r = 0.18), social support (r = -0.28), activities of daily living (r = -0.43), subjective health (r = -0.28), autonomy (r = -0.41), environment (r = -0.50) and physical (r = -0.57) and psychological health (r = -0.65). CONCLUSION: The prevalence of depressive mood is high among nursing home residents, especially in lower-middle-income countries. It is influenced by factors including gender, income, social support, daily activities, environment, physical and psychological health and autonomy. Understanding those factors can provide evidence-based recommendations for improved awareness, prevention and better management of late-life depression.

4.
IEEE Trans Cybern ; PP2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959152

RESUMO

Hybridization plays a prominent role in bolstering the performance of optimization algorithms (OAs), yet designing efficient hybrid OAs tailored to intricate optimization problems persists as a formidable task. This article introduces a novel top-down methodology for the automated design of hybrid OAs, treating algorithm design as a meta-optimization problem. A general design template for collaboration-based hybrid OAs is developed, integrating a multitude of hybridization strategies for the first time. Besides, a mathematical model is built to formulate the meta-optimization problem of algorithm design. To address the meta-optimization challenge, an improved multifactorial evolutionary algorithm is proposed to automatically design efficient hybrid metaheuristics in a multitasking environment for the given instances with diverse features. To verify the effectiveness of the proposed design methodology, it is applied to the CEC2017 benchmark functions and the binary knapsack problem. Numerical results have demonstrated the feasibility and effectiveness of the proposed methodology for both continuous and combinatorial optimization benchmarks.

5.
Tissue Cell ; 89: 102453, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38964085

RESUMO

AIMS: Baicalin is a flavonoid derived from the root of the medicinal plant Scutellaria baicalensis Georgi (S. baicalensis) and is known for its various pharmacological properties. This study aimed to investigate the impact of baicalin (BAI) on the occurrence of kidney calcium oxalate crystal formation induced by ethylene glycol in male SD rats. MAIN METHODS: A rat model of renal stones was created and various concentrations of baicalin were used for intervention. Samples of urine, blood, and kidney tissue were taken from the rats, and they were euthanized for biochemical and histopathological examinations. KEY FINDINGS: Our results show that baicalin treatment improved the weight loss induced by ethylene glycol (EG) and ammonium chloride (AC) in rats. Baicalin also reduced the formation of calcium oxalate crystals and protected kidney function in rats with urolithiasis. Furthermore, it lowered the level of malondialdehyde (MDA) and elevated the activity of antioxidant enzymes compared to the stone control group. Additionally, baicalin notably alleviated renal inflammation in rats with urolithiasis. SIGNIFICANCE: The present study attributed clinical evidence first time that claiming the significant antiurolithic effect of baicalin and could be a cost-effective candidate for the prevention and treatment of urolithiasis.

6.
Food Chem ; 458: 140204, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38964092

RESUMO

The bacterial derived osmolyte ectoine has been shown to stabilize cell structure and function, a property that may help to extend the shelf life of broccoli. The impact of ectoine on broccoli stored for 4 d at 20 °C and 90% relative humidity was investigated. Results indicated that 0.20% ectoine treatment maintained the quality of broccoli, by reducing rate of respiration and ethylene generation, while increasing the levels of total phenolics, flavonoids, TSS, soluble protein, and vitamin C, relative to control. Headspace-gas chromatography-mass spectrometry, transcriptomic and metabolomic analyses revealed that ectoine stabilized aroma components in broccoli by maintaining level of volatile compounds and altered the expression of genes and metabolites associated with sulfur metabolism, as well as fatty acid and amino acid biosynthesis pathways. These findings provide a greater insight into how ectoine preserves the flavor and nutritional quality of broccoli, thus, extending its shelf life.

7.
BMC Public Health ; 24(1): 1775, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961448

RESUMO

BACKGROUND: Being subjected to bullying is a significant risk factor for non-suicidal self-injury (NSSI) among adolescents. Parental support, peer support, and social connectedness play protective roles in mitigating NSSI in this population. However, the precise impact of the combined effects of parental and peer support on bullying and NSSI requires further investigation. METHODS: This study employed the Child and Adolescent Social Support Scale, Delaware Bullying Victimisation Scale, Social Connectedness Scale, and the Ottawa Self-Injury Inventory to survey 1277 Chinese adolescents. Polynomial regression analysis and response surface analysis were applied to examine the mediating role of bullying and social connectedness in the relationship between parental and peer support matching and NSSI. RESULTS: The results indicate that parental support (r = 0.287, P < 0.001), peer support (r = 0.288, P < 0.001), and social connectedness (r = 0.401, P < 0.001) were protective factors against NSSI in adolescents. Conversely, bullying (r = 0.425, P < 0.001) acts as a risk factor for NSSI in this population. Adolescents with low parental and peer support experienced more bullying than those with high parental and peer support, while those with low parental but high peer support experienced less bullying than those with high parental but low peer support (R^2 = 0.1371, P < 0.001). Social connectedness moderated the effect between bullying and NSSI in this model (ß = 0.006, P < 0.001). LIMITATIONS: Due to the under-representation of participants and lack of longitudinal data support, the explanatory power of causality between variables was limited. Future studies should include national samples and incorporate longitudinal studies to enhance the generalisability and robustness of the findings. CONCLUSION: This study reveals the influence mechanism of parental and peer support matching experienced by adolescents on bullying and NSSI and the moderating role of social connectedness. These findings enrich the developmental theory of adolescent NSSI and provide reference for the prevention and intervention of adolescent NSSI behaviour.


Assuntos
Bullying , Grupo Associado , Comportamento Autodestrutivo , Apoio Social , Humanos , Bullying/psicologia , Bullying/estatística & dados numéricos , Adolescente , Masculino , Feminino , China , Comportamento Autodestrutivo/psicologia , Relações Pais-Filho , Fatores de Risco , Comportamento do Adolescente/psicologia , Inquéritos e Questionários , Criança , Pais/psicologia
8.
Nucleic Acids Res ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967005

RESUMO

High spontaneous mutation rate is crucial for obtaining ideal phenotype and exploring the relationship between genes and phenotype. How to break the genetic stability of organisms and increase the mutation frequency has become a research hotspot. Here, we present a practical and controllable evolutionary tool (oMut-Cgts) based on dual genetic level modification engineering for Corynebacterium glutamicum. Firstly, the modification engineering of transcription and replication levels based on RNA polymerase α subunit and DNA helicase Cgl0854 as the 'dock' of cytidine deaminase (pmCDA1) significantly increased the mutation rate, proving that the localization of pmCDA1 around transient ssDNA is necessary for genome mutation. Then, the combined modification and optimization of engineering at dual genetic level achieved 1.02 × 104-fold increased mutation rate. The genome sequencing revealed that the oMut-Cgts perform uniform and efficient C:G→T:A transitions on a genome-wide scale. Furthermore, oMut-Cgts-mediated rapid evolution of C. glutamicum with stress (acid, oxidative and ethanol) tolerance proved that the tool has powerful functions in multi-dimensional biological engineering (rapid phenotype evolution, gene function mining and protein evolution). The strategies for rapid genome evolution provided in this study are expected to be applicable to a variety of applications in all prokaryotic cells.

9.
Front Neurol ; 15: 1415760, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978815

RESUMO

Background: Migraine is a global public health concern, affecting both social and individual well-being. Calcitonin gene-related peptide (CGRP), a crucial neuropeptide, holds important research value in understanding migraine pathogenesis. CGRP receptor antagonists and monoclonal antibodies that target CGRP or its receptors have shown efficacy in reducing migraine frequency and severity, presenting a promising therapeutic approach. This study aimed to conduct a comprehensive bibliometric analysis to analyze the current state, research trends, and future directions of CGRP in migraine. Methods: Bibliometric tools including CiteSpace, VOSviewer, etc., were utilized to extract and summarize publications related to CGRP in migraine from the Web of Science Core Collection Database (WOSCC) between 2004 and 2023, as of December 31, 2023. The analysis focused on trends in annual publications, leading countries/regions and institutions, prominent journals and references, influential authors, and high-frequency keywords in the field. Results: A total of 1,821 articles and reviews involving 5,180 authors from 1,315 organizations across 64 countries were included in the study. These publications were distributed across 362 journals and accumulated 56,999 citations by December 31, 2023. An increasing trend was observed in annual publications on CGRP in migraine. The United States emerged as the leading nation in both publications and citations, with academic Peter Goadsby contributing the highest number of publications. The University of Copenhagen stood out as the institution with the most publications, and Cephalalgia emerged as the most influential journal. The most cited paper identified was "Calcitonin gene-related peptide receptor antagonist BIBN4096BS for the acute treatment of migraine" by Jes Olesen, published in the New Engl Med. Keyword frequency analysis revealed prevalent terms such as "migraine," "CGRP," and "episodic migraine," along with emerging topics represented by keywords including "trial," "monoclonal antibodies," "preventive treatment," and "safety." Conclusion: CGRP is pivotal in migraine pathogenesis, and there is a robust research foundation exploring its role. The US leads in research output on CGRP in migraine. Investigating the mechanism of CGRP and its receptor in migraine remains a key area of interest, particularly focusing on signaling pathways. Future research should target identifying critical therapeutic targets in CGRP antagonist pathways for migraine treatment.

10.
Plant J ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38981001

RESUMO

Understanding and optimizing the process of grain filling helps the quest to maximize rice (Oryza sativa L.) seed yield and quality, yet the intricate mechanisms at play remain fragmented. Transcription factors (TFs) are major players in the gene networks underlying the grain filling process. Here, we employed grain incomplete filling (OsGIF1)/cell wall invertase 2, a key gene involved in grain filling, to explore its upstream TFs and identified a bZIP family TF, OsbZIP10, to be a transcriptional activator of OsGIF1. Rice grains of the knockouts of OsbZIP10 showed increased white-core rates but lower amylose content (AC), leading to better eating and cooking qualities in all genetic backgrounds investigated, though the impact of mutations in OsbZIP10 on grain weight depended on genetic background. Multi-omics analyses suggested that, in addition to OsGIF1, multiple genes involved in different biological processes contributing to grain filling were targeted by OsbZIP10, including OsAGPS1, a gene encoding the ADP-Glc pyrophosphorylase (AGPase) small subunit, and genes contributing to homeostasis of reactive oxygen species. Distinct genetic make-up was observed in OsbZIP10 between japonica and indica rice varieties, with the majority varieties of each subspecies belonging to two different haplotypes that were closely associated with AC. Overexpressing the haplotype linked to high-AC in the low-AC genetic background increased AC. Overall, this study sheds crucial light on the significance of the OsbZIP10-OsGIF1 module in the determination of rice grain quality, offering a potential avenue for genetic engineering of rice to produce seeds with tailored attributes.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 322: 124790, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38981286

RESUMO

Interactions of water and chemical or bio-compound have a universal concern and have been extensively studied. For spectroscopic analysis, the complexity and the low resolution of the spectra make it difficult to obtain the spectral features showing the interactions. In this work, the structures and interactions in gaseous water and water-alcohol mixtures were studied using high-resolution infrared (HR-IR) spectroscopy. The spectral features of water clusters of different sizes, including dimer, trimer, tetramer and pentamer, were observed from the measured spectra of the samples in different volume concentrations, and the interactions of water and methanol/ethanol in the mixtures were obtained. In the analysis, a method based on principal component analysis was used to separate the overlapping spectra. In water-alcohol mixtures, when water is less, water molecules tend to interact with the OH groups on the exterior of the alcohol aggregate, and with the increase of water, a water cage forms around the aggregates. Furthermore, the ratio of the molecule number of methanol in the aggregate to that of water in the cage is around 1:2.3, and the ratio for ethanol is about 1:3.2.

12.
Angew Chem Int Ed Engl ; : e202409750, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38982974

RESUMO

Splitting the five and seven-membered rings of azulene and embedding them separately into a conjugated backbone provides azulene-like polycyclic aromatic hydrocarbons (PAHs), which are of great interest in quantum and material chemistry. However, the synthetic accessibility poses a significant challenge. In this study, we present the synthesis of a novel azulene-like PAH, Pery-57, which can be viewed as the integration of a perylene framework into the split azulene. The compact structure of Pery-57 displays several intriguing characteristics, including NIR II absorption at 1200 nm, a substantial dipole moment of 3.5 D, and head-to-tail alternating columnar packing. Furthermore, Pery-57 exhibits remarkable redox properties. The cationic radical Pery-57•+ readily captures a hydrogen atom. Variable-temperature NMR (VT-NMR) and variable-temperature EPR (VT-EPR) studies reveal that the dianion Pery-572- possesses an open-shell singlet ground state and demonstrates significant global anti-aromaticity. The dication Pery-572+ is also predicted to exhibit diradical character. Despite bearing three bulky substituents, Pery-57 displays p-type transport characteristics with a mobility of 0.03 cm2 V-1 s-1, attributed to its unique azulene-like structure. Overall, this work directs interest in azulene-like PAHs, a unique member of nonalternant PAHs showcasing exceptional properties and applications.

13.
Psychol Res ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985171

RESUMO

Emotions powerfully, predictably, and pervasively influence decision making. The risk-as-feelings hypothesis states that two kinds of emotions are important in decision-making, anticipatory emotions and anticipated emotions. We empirically investigated whether and how anticipatory and anticipated emotions may change as a function of outcome values and whether anticipatory or anticipated emotions may explain the influence of outcome values on risky choice. To study the effects of value on emotions and choice, we offered people hypothetical large amounts ($100, $200, $300, $400) and incentivized moderate amounts ($10, $20, $30, $40) as prospects in gambles over two consecutive studies. Using a representative sample from the US to ensure the generalizability of the findings, each participant in our two studies made choices in gain and loss domains. Overall, anticipatory and anticipated emotions responded very similarly to changes in value for the sure gains in both studies. The findings also indicated that both anticipatory and anticipated emotions explained the effects of the value on choice for the sure gain and sure losses, while both mediated the effect of framing on choice towards the sure and the gamble option. Although anticipatory emotions mediated a larger portion of the effect, anticipated emotions also show some mediation.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38995226

RESUMO

Alveolar bone loss is generally considered as a chronological age-related disease. As biological ageing process is not absolutely determined by increasing age, whether alveolar bone loss associated with increasing chronological age or biological ageing remains unclear. Accurately distinguishing whether alveolar bone loss is chronological age-related or biological ageing-related is critical for selecting appropriate clinical treatments. This study aimed to identify the relationship between alveolar bone loss and body ageing. 3635 participants from National Health and Nutrition Examination Survey and 71 living kidney transplant recipients from Gene Expression Omnibus Datasets were enrolled. Multivariate regression analysis, smooth curve fittings and generalized additive models were used to explore the association among alveolar bone loss, age, serum α-Klotho level, renal function markers, as well as between preoperative creatinine and renal cortex related α-Klotho gene expression level. Meanwhile, a two-sample Mendelian randomization study was conducted to assess the causal relationship between α-Klotho and periodontal disease (4,376 individuals versus 361,194 individuals). As biological ageing related indicator, α-Klotho level was negatively correlated with impaired renal function and alveolar bone loss. Correspondingly, accompanied by decreasing renal function, it was manifested with down-regulated expression level of α-Klotho in renal cortex and aggravated alveolar bone loss. The MR analysis further identified the negative association between higher genetically predicted α-Klotho concentrations with alveolar bone loss susceptibility using the IVW (OR=0.999, P=0.005). However, an inversely U-shaped association was observed between chronological age and alveolar bone loss, which especially stable in men (the optimal cut-off values were both 62 years old). For male above 62 years old, increasing age converted to protective factor and accompanied by alleviated alveolar bone loss. Alveolar bone loss which directly associated to decreased renal function and α-Klotho level was related to biological ageing rather than chronological age. The renal-alveolar bone axis could provide new sight of clinical therapy in alveolar bone loss.

15.
Diabetes Metab Syndr Obes ; 17: 2627-2638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974949

RESUMO

Background: In elderly diabetic patients, depression is often overlooked because professional evaluation requires psychiatrists, but such specialists are lacking in the community. Therefore, we aimed to create a simple depression screening model that allows earlier detection of depressive disorders in elderly diabetic patients by community health workers. Methods: The prediction model was developed in a primary cohort that consisted of 210 patients with diabetes, and data were gathered from December 2022 to February 2023. The independent validation cohort included 99 consecutive patients from February 2023 to March 2023. Multivariable logistic regression analysis was used to develop the predictive model. We incorporated common demographic characteristics, diabetes-specific factors, family structure characteristics, the self-perceived burden scale (SPBS) score, and the family APGAR (adaptation, partnership, growth, affection, resolution) score. The performance of the nomogram was assessed with respect to its calibration (calibration curve, the Hosmer-Lemeshow test), discrimination (the area under the curve (AUC)), and clinical usefulness (Decision curve analysis (DCA)). Results: The prediction nomogram incorporated 5 crucial factors such as glucose monitoring status, exercise status, monthly income, sleep disorder status, and the SPBS score. The model demonstrated strong discrimination in the primary cohort, with an AUC of 0.839 (95% CI, 0.781-0.897). This discriminative ability was further validated in the validation cohort, with an AUC of 0.857 (95% CI, 0.779-0.935). Moreover, the nomogram exhibited satisfactory calibration. DCA suggested that the prediction of depression in elderly patients with diabetes mellitus was of great clinical value. Conclusion: The prediction model provides precise and user-friendly guidance for community health workers in preliminary screenings for depression among elderly patients with diabetes.

16.
bioRxiv ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38979280

RESUMO

Aging is associated with a decline in the number and fitness of adult stem cells 1-4 . Aging-associated loss of stemness is posited to suppress tumorigenesis 5,6 , but this hypothesis has not been tested in vivo . Here, using physiologically aged autochthonous genetically engineered mouse models and primary cells 7,8 , we demonstrate aging suppresses lung cancer initiation and progression by degrading stemness of the alveolar cell of origin. This phenotype is underpinned by aging-associated induction of the transcription factor NUPR1 and its downstream target lipocalin-2 in the cell of origin in mice and humans, leading to a functional iron insufficiency in the aged cells. Genetic inactivation of the NUPR1-lipocalin-2 axis or iron supplementation rescue stemness and promote tumorigenic potential of aged alveolar cells. Conversely, targeting the NUPR1- lipocalin-2 axis is detrimental to young alveolar cells via induction of ferroptosis. We find that aging-associated DNA hypomethylation at specific enhancer sites associates with elevated NUPR1 expression, which is recapitulated in young alveolar cells by inhibition of DNA methylation. We uncover that aging drives a functional iron insufficiency, which leads to loss of stemness and tumorigenesis, but promotes resistance to ferroptosis. These findings have significant implications for the therapeutic modulation of cellular iron homeostasis in regenerative medicine and in cancer prevention. Furthermore, our findings are consistent with a model whereby most human cancers initiate in young individuals, revealing a critical window for such cancer prevention efforts.

17.
Metab Brain Dis ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39002017

RESUMO

Ischemic stroke is the most important cause of disability and death worldwide, but current treatments remain limited. Traditional Chinese medicine (TCM) including the herb pair of Zhiqiao-Danggui (ZD) offers a multifaceted treatment approach through promoting blood circulation, yet its specific anti-ischemic mechanism remains unclear. This study used the photochemically induced thrombosis (PIT) mouse model and the oxygen glucose deprivation/reoxygenation (OGD/R) cell model to explore the therapeutic effect of ZD on ischemic stroke. Mice were treated with high and low doses of ZD extract or positive control. Behavior was assessed using the grid test. The brain tissue was then subjected to infarct volume assessment, histopathology, oxidative stress marker detection, LC/MS metabolomic analysis and qRT-PCR validation. The therapeutic effect of ZD-medicated serum on OGD/R model was tested on cells. Experimental results show that ZD can improve motor function, reduce infarct size, neuronal damage and apoptosis as well as alleviate oxidative stress in mice. ZD-medicated serum promotes endothelial cell proliferation, improves cell survival against OGD/R-induced injury, reduces oxidative damage and protects mitochondrial function. Metabolomics reveals ZD regulation of metabolites in energy metabolism, amino acid metabolism, TCA cycle, and angiogenesis signaling pathways. qRT-PCR results also showed that ZD could attenuate abnormal conduction of angiogenic signals and enhance vessel stability. This study confirmed the neuroprotective and vasoprotective effects of ZD, highlighted its potential in treating ischemic stroke, and provided a scientific basis for the traditional use of ZD.

18.
Phys Rev Lett ; 132(26): 266602, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38996328

RESUMO

Twisted moiré materials, a new class of layered structures with different twist angles for neighboring layers, are attracting great attention because of the rich intriguing physical phenomena associated with them. Of particular interest are the topological network modes, first proposed in the small angle twisted bilayer graphene under interlayer bias. Here we report the observations of such topological network modes in twisted moiré phononic crystals without requiring the external bias fields. Acoustic topological network modes that can be constructed in a wide range of twist angles are both observed in the domain walls with and without reconstructions, which serve as the analogy of the lattice relaxations in electronic moiré materials. Topological robustness of the topological network modes is observed by introducing valley-preserved defects to the network channel. Furthermore, the network can be reconfigured into two-dimensional patterns with any desired connectivity, offering a unique prototype platform for acoustic applications.

19.
World J Microbiol Biotechnol ; 40(9): 267, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39004689

RESUMO

As an efficient and safe industrial bacterium, Corynebacterium glutamicum has extensive application in amino acid production. However, it often faces oxidative stress induced by reactive oxygen species (ROS), leading to diminished production efficiency. To enhance the robustness of C. glutamicum, numerous studies have focused on elucidating its regulatory mechanisms under various stress conditions such as heat, acid, and sulfur stress. However, a comprehensive review of its defense mechanisms against oxidative stress is needed. This review offers an in-depth overview of the mechanisms C. glutamicum employs to manage oxidative stress. It covers both enzymatic and non-enzymatic systems, including antioxidant enzymes, regulatory protein families, sigma factors involved in transcription, and physiological redox reduction pathways. This review provides insights for advancing research on the antioxidant mechanisms of C. glutamicum and sheds light on its potential applications in industrial production.


Assuntos
Antioxidantes , Proteínas de Bactérias , Corynebacterium glutamicum , Regulação Bacteriana da Expressão Gênica , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio , Fator sigma , Corynebacterium glutamicum/metabolismo , Corynebacterium glutamicum/genética , Antioxidantes/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Espécies Reativas de Oxigênio/metabolismo , Fator sigma/metabolismo , Fator sigma/genética
20.
Environ Pollut ; : 124591, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39043311

RESUMO

Marine microplastics (MPs) pollution, with rivers as a major source, leads to MPs accumulation in estuarine sediments, which are also nitrogen cycling hotspots. However, the impact of MPs on nitrogen cycling in estuarine sediments has rarely been documented. In this study, we conducted microcosm experiment to investigate the effects of commonly encountered polyethylene (PE) and polystyrene (PS) MPs, with two MPs concentrations (0.3% and 3% wet sediment weight) based on environmental concentration considerations and dose-response effects, on sediment dissolved oxygen (DO) diffusion capacity and microbial communities using microelectrode system and metagenomic analysis respectively. The results indicated that high concentrations of PE-MPs inhibited DO diffusion during the mid-phase of the experiment, an effect that dissipated in the later stages. Metagenomic analysis revealed that MP treatments reduced the relative abundance of dominant microbial colonies in the sediments. The PCoA results demonstrated that MPs altered the microbial community structure, particularly evident under high concentration PE-MPs treatments. Functional analysis related to the nitrogen cycle suggested that PS-MPs promoted the nitrification, denitrification, and DNRA processes, but inhibited the ANRA process, while PE-MPs had an inhibitory effect on the nitrate reduction process and the ANRA process. Additionally, the high concentration of PE-MPs treatment significantly stimulated the abundance of genus (Bacillus) by 34.1% and genes (lip, pnbA) by 100-187.5% associated with plastic degradation, respectively. Overall, in terms of microbial community structure and the abundance of nitrogen cycling functional genes, PE- and PS- MPs exhibit both similarities and differences in their impact on nitrogen cycling. Our findings highlight the complexity of MP effects on nitrogen cycling in estuarine sediments and high concentrations of PE-MP stimulated plastic-degrading genus and genes.

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