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1.
J Int Med Res ; 52(4): 3000605241240579, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38603605

RESUMO

The mortality rate of gastric varices bleeding can reach 20% within 6 weeks. Isolated gastric varices (IGVs) refer to gastric varices without esophageal varices and typically arise as a common complication of left portal hypertension. Although IGVs commonly form in the setting of splenic vein occlusion, the combination of antiphospholipid syndrome and protein S deficiency leading to splenic vein occlusion is rare. We herein present a case of a 28-year-old woman with intermittent epigastric pain and melena. She was diagnosed with antiphospholipid syndrome based on the triad of pregnancy morbidity, unexplained venous occlusion, and positive lupus anticoagulant. Laparoscopic splenectomy and pericardial devascularization were performed for the treatment of IGVs. During the 6-month postoperative follow-up, repeated endoscopy and contrast-enhanced computed tomography revealed disappearance of the IGVs. This is the first description of splenic vein occlusion associated with both antiphospholipid syndrome and protein S deficiency. We also provide a review of the etiology, clinical manifestations, diagnosis, and treatment methods of IGVs.


Assuntos
Síndrome Antifosfolipídica , Varizes Esofágicas e Gástricas , Deficiência de Proteína S , Doenças Vasculares , Feminino , Humanos , Adulto , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/diagnóstico , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/diagnóstico , Deficiência de Proteína S/complicações , Hemorragia Gastrointestinal/etiologia , Doenças Vasculares/complicações
2.
Part Fibre Toxicol ; 21(1): 17, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561847

RESUMO

BACKGROUND: Amorphous silica nanoparticles (SiNPs) have been gradually proven to threaten cardiac health, but pathogenesis has not been fully elucidated. Ferroptosis is a newly defined form of programmed cell death that is implicated in myocardial diseases. Nevertheless, its role in the adverse cardiac effects of SiNPs has not been described. RESULTS: We first reported the induction of cardiomyocyte ferroptosis by SiNPs in both in vivo and in vitro. The sub-chronic exposure to SiNPs through intratracheal instillation aroused myocardial injury, characterized by significant inflammatory infiltration and collagen hyperplasia, accompanied by elevated CK-MB and cTnT activities in serum. Meanwhile, the activation of myocardial ferroptosis by SiNPs was certified by the extensive iron overload, declined FTH1 and FTL, and lipid peroxidation. The correlation analysis among detected indexes hinted ferroptosis was responsible for the SiNPs-aroused myocardial injury. Further, in vitro tests, SiNPs triggered iron overload and lipid peroxidation in cardiomyocytes. Concomitantly, altered expressions of TfR, DMT1, FTH1, and FTL indicated dysregulated iron metabolism of cardiomyocytes upon SiNP stimuli. Also, shrinking mitochondria with ridge fracture and ruptured outer membrane were noticed. To note, the ferroptosis inhibitor Ferrostatin-1 could effectively alleviate SiNPs-induced iron overload, lipid peroxidation, and myocardial cytotoxicity. More importantly, the mechanistic investigations revealed miR-125b-2-3p-targeted HO-1 as a key player in the induction of ferroptosis by SiNPs, probably through regulating the intracellular iron metabolism to mediate iron overload and ensuing lipid peroxidation. CONCLUSIONS: Our findings firstly underscored the fact that ferroptosis mediated by miR-125b-2-3p/HO-1 signaling was a contributor to SiNPs-induced myocardial injury, which could be of importance to elucidate the toxicity and provide new insights into the future safety applications of SiNPs-related nano products.


Assuntos
Ferroptose , Sobrecarga de Ferro , MicroRNAs , Nanopartículas , Humanos , Miócitos Cardíacos , Dióxido de Silício/metabolismo , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Ferro/metabolismo , Ferro/farmacologia , MicroRNAs/metabolismo , Nanopartículas/toxicidade
3.
Sci Data ; 11(1): 396, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637640

RESUMO

Stag beetles (Coleoptera: Lucanidae) represent a significant saproxylic assemblage in forest ecosystems and are noted for their enlarged mandibles and male polymorphism. Despite their relevance as ideal models for the study of exaggerated mandibles that aid in attracting mates, the regulatory mechanisms associated with these traits remain understudied, and restricted by the lack of high-quality reference genomes for stag beetles. To address this limitation, we successfully assembled the first chromosome-level genome of a representative species Dorcus hopei. The genome was 496.58 Mb in length, with a scaffold N50 size of 54.61 Mb, BUSCO values of 99.8%, and 96.8% of scaffolds anchored to nine pairs of chromosomes. We identified 285.27 Mb (57.45%) of repeat sequences and annotated 11,231 protein-coding genes. This genome will be a valuable resource for further understanding the evolution and ecology of stag beetles, and provides a basis for studying the mechanisms of exaggerated mandibles through comparative analysis.


Assuntos
Besouros , Genoma de Inseto , Animais , Masculino , Besouros/genética , Florestas , Filogenia , Polimorfismo Genético , Cromossomos de Insetos
4.
Arch Insect Biochem Physiol ; 115(4): e22113, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628056

RESUMO

The efficiency of RNA interference (RNAi) has always limited the research on the phenotype innovation of Lepidoptera insects. Previous studies have found that double-stranded RNA-degrading enzyme (dsRNase) is an important factor in RNAi efficiency, but there have been no relevant reports in butterflies (Papilionoidea). Papilio xuthus is one of the important models in butterflies with an extensive experimental application value. To explore the effect of dsRNase in the RNAi efficiency on butterflies, six dsRNase genes (PxdsRNase 1-6) were identified in P. xuthus genome, and their dsRNA-degrading activities were subsequently detected by ex vivo assays. The result shows that the dsRNA-degrading ability of gut content (<1 h) was higher than hemolymph content (>12 h). We then investigated the expression patterns of these PxdsRNase genes during different tissues and developmental stages, and related RNAi experiments were carried out. Our results show that different PxdsRNase genes had different expression levels at different developmental stages and tissues. The expression of PxdsRNase2, PxdsRNase3, and PxdsRNase6 were upregulated significantly through dsGFP injection, and PxdsRNase genes can be silenced effectively by injecting their corresponding dsRNA. RNAi-of-RNAi studies with PxEbony, which acts as a reporter gene, observed that silencing PxdsRNase genes can increase RNAi efficiency significantly. These results confirm that silencing dsRNase genes can improve RNAi efficiency in P. xuthus significantly, providing a reference for the functional study of insects such as butterflies with low RNAi efficiency.


Assuntos
Borboletas , Animais , Borboletas/genética , Interferência de RNA , RNA de Cadeia Dupla , Insetos/genética , Inativação Gênica
5.
J Biochem Mol Toxicol ; 38(4): e23698, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38501767

RESUMO

Accumulating evidence confirms that sleep insufficiency is a high risk factor for cognitive impairment, which involves inflammation and synaptic dysfunction. Resveratrol, an agonist of the Sirt1, has demonstrated anti-inflammation and neuroprotective effects in models of Alzheimer's disease, Parkinson's disease, and schizophrenia. However, the beneficial effects of resveratrol on sleep deprivation-induced cognitive deficits and its underlying molecular mechanisms are unclear. In the present study, thirty-two male C57BL/6 J mice were randomly divided into a Control+DMSO group, Control+Resveratrol group, SD+DMSO group, and SD+Resveratrol group. The mice in the SD+Resveratrol group underwent 5 days of sleep deprivation after pretreatment with resveratrol (50 mg/kg) for 2 weeks, while the mice in the SD+DMSO group only underwent sleep deprivation. After sleep deprivation, we evaluated spatial learning and memory function using the Morris water maze test. We used general molecular biology techniques to detect changes in levels of pro-inflammatory cytokines and Sirt1/miR-134 pathway-related synaptic plasticity proteins. We found that resveratrol significantly reversed sleep deprivation-induced learning and memory impairment, elevated interleukin-1ß, interleukin-6, and tumor necrosis factor-α levels, and decreased brain-derived neurotrophic factor, tyrosine kinase receptor B, postsynaptic density protein-95, and synaptophysin levels by activating the Sirt1/miR-134 pathway. In conclusion, resveratrol is a promising agent for preventing sleep deprivation-induced cognitive dysfunction by reducing pro-inflammatory cytokines and improving synaptic function via the Sirt1/miR-134 pathway.


Assuntos
Disfunção Cognitiva , MicroRNAs , Masculino , Camundongos , Animais , Resveratrol/farmacologia , Privação do Sono/complicações , Privação do Sono/metabolismo , Sirtuína 1/metabolismo , Dimetil Sulfóxido/metabolismo , Dimetil Sulfóxido/farmacologia , Camundongos Endogâmicos C57BL , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Hipocampo/metabolismo , MicroRNAs/metabolismo , Citocinas/metabolismo , Cognição
6.
Photochem Photobiol Sci ; 23(4): 719-729, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38441849

RESUMO

The bioluminescence system of luminescent beetles has extensive applications in biological imaging, protein labeling and drug screening. To explore wild luciferases with excellent catalytic activity and thermal stability, we cloned the luciferase of Pygoluciola qingyu, one species living in areas of high temperature and with strong bioluminescence, by combining transcriptomic sequencing and reverse transcription polymerase chain reaction (RT-PCR). The total length of luciferase gene is 1638 bp and the luciferase consists 544 amino acids. The recombinant P. qingyu luciferase was produced in vitro and its characteristics were compared with those of eight luciferases from China firefly species and two commercial luciferases. Compared with these luciferases, the P. qingyu luciferase shows the highest luminescence activity at room temperature (about 25-28 â„ƒ) with similar KM value for D-luciferin and ATP to the Photinus pyralis luciferase. The P. qingyu luciferase activity was highest at 35 â„ƒ and can keep high activity at 30-40 â„ƒ, which suggests the potential of P. qingyu luciferase for in vivo and cell application. Our results provide new insights into P. qingyu luciferase and give a new resource for the application of luciferases.


Assuntos
Besouros , Vaga-Lumes , Animais , Vaga-Lumes/genética , Besouros/genética , Besouros/metabolismo , Sequência de Aminoácidos , Luciferases/química , Luciferases de Vaga-Lume/metabolismo , Clonagem Molecular , Medições Luminescentes
7.
Sleep Med ; 117: 162-168, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38547593

RESUMO

BACKGROUND AND OBJECTIVE: Rumination, a common factor of chronic insomnia disorder (CID) caused by cognitive-emotional arousal, is associated with an increased amount of rapid eye movement (REM) sleep. However, the specific subtypes, such as phasic REM and tonic REM, that contribute to the increased REM sleep have not been reported. This study aimed to determine the association between rumination and different REM sleep subtypes in patients with CID. METHODS: This study enrolled 35 patients with CID and 27 age- and sex-matched healthy controls. The Immersion-Rumination Questionnaire evaluated participants' rumination, and the Insomnia Severity Index was used to assess insomnia severity. Finally, polysomnography was used to monitor objective sleep quality and quantification of different types of REM. RESULTS: The CID patients had higher rumination scores than the healthy controls. They had a shorter REM sleep duration, less phasic REM, a lower percentage of phasic REM time, and a higher percentage of tonic REM time. Spectral analysis revealed that the patients affected by insomnia had higher ß power during REM sleep, higher ß and σ power during phasic REM sleep, and higher ß, and γ power during tonic REM sleep. Partial correlation analysis showed that rumination in the CID patients correlated negatively with the duration of phasic REM sleep. Additionally, rumination correlated negatively with δ power in REM sleep and positively with ß power in REM sleep, tonic REM sleep, phasic REM sleep, N3and N2 sleep in the patients with CID. CONCLUSION: The CID patients had stronger rumination, reduced total and phasic REM sleep, and the stronger rumination was, the shorter phasic REM was and the higher fast (ß) wave power in REM sleep.


Assuntos
Transtorno do Comportamento do Sono REM , Distúrbios do Início e da Manutenção do Sono , Humanos , Sono REM , Distúrbios do Início e da Manutenção do Sono/complicações , Polissonografia , Nível de Alerta , Transtorno do Comportamento do Sono REM/complicações
8.
Sleep Med ; 117: 177-183, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554533

RESUMO

OBJECTIVES: To explore the relationship between nocturnal levels of stress-related hormones and different sleep-wake states in chronic insomnia disorder (CID) patients. METHODS: Thirty-three CID patients and 34 good sleepers were enrolled and completed assessment of sleep log, Pittsburgh Sleep Quality Index and Insomnia Severity Index. During a-overnight polysomnography monitoring, the patients' vein bleeds were continually collected at different time points (pre-sleep, deep-sleep, 5-min or 30-min waking, and morning waking-up). The control subjects' bleeds were collected only at 22:00 and morning waking-up. The serum hormones were detected using enzyme-linked immunosorbent assay. RESULTS: Compared with at pre-sleep, the level of cortisol was significantly higher at morning waking-up respectively in two-group subjects (Ps < 0.001), with insignificant inter-group differences in cortisol, corticotropin releasing hormone and copeptin at the two time-points. In the patients, the nocturnal secretion curves of three hormones were similar, with the highest concentration at morning waking-up, followed by 30-min waking, 5-min waking, pre-sleep, and deep-sleep. The patients' cortisol (Z = 79.192, P < 0.001) and copeptin (Z = 12.333, P = 0.015) levels were statistically different at different time-points, with higher cortisol at morning waking-up relative to deep-sleep, pre-sleep and 5-min waking (Ps < 0.05), and at 30-min waking relative to deep-sleep and pre-sleep (Ps < 0.05), and higher copeptin at morning waking-up relative to deep-sleep (P < 0.05). CONCLUSIONS: In CID, the nocturnal wakes were instantaneously accompanied by high level, and deep sleep was accompanied by the lowest levels, of stress-related hormones, especially in cortisol, supporting the insomniac hypothesis of increased nocturnal pulse-release of cortisol.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Projetos Piloto , Hidrocortisona , Sono , Polissonografia
9.
Chin Med ; 19(1): 49, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519984

RESUMO

Respiratory diseases, marked by structural changes in the airways and lung tissues, can lead to reduced respiratory function and, in severe cases, respiratory failure. The side effects of current treatments, such as hormone therapy, drugs, and radiotherapy, highlight the need for new therapeutic strategies. Traditional Chinese Medicine (TCM) offers a promising alternative, leveraging its ability to target multiple pathways and mechanisms. Active compounds from Chinese herbs and other natural sources exhibit anti-inflammatory, antioxidant, antitumor, and immunomodulatory effects, making them valuable in preventing and treating respiratory conditions. Ferroptosis, a unique form of programmed cell death (PCD) distinct from apoptosis, necrosis, and others, has emerged as a key area of interest. However, comprehensive reviews on how natural products influence ferroptosis in respiratory diseases are lacking. This review will explore the therapeutic potential and mechanisms of natural products from TCM in modulating ferroptosis for respiratory diseases like acute lung injury (ALI), asthma, pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD), lung ischemia-reperfusion injury (LIRI), pulmonary hypertension (PH), and lung cancer, aiming to provide new insights for research and clinical application in TCM for respiratory health.

10.
Int J Biol Macromol ; 265(Pt 2): 130898, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508556

RESUMO

Anti-infection hydrogels have recently aroused enormous attraction, particularly in the treatment of chronic wounds. Herein, silver nanoparticle@catechol formaldehyde resin microspheres (Ag@CFRs) were fabricated by one-step hydrothermal method and subsequently encapsulated in hydrogels which were developed by Schiff base reaction between aldehyde groups in oxidized hyaluronic acid and amino groups in carboxymethyl chitosan. The developed polysaccharide hydrogel exhibited microporous structure, high swelling capacity, favorable mechanical strength, enhanced tissue adhesion and photothermal activities. Additionally, the hydrogel not only ensured long-term and high-efficiency antibacterial performance (99.9 %) toward E. coli and S. aureus, but also realized superior cytocompatibility in vitro. Moreover, based on the triple antibacterial strategies endowed by chitosan, silver nanoparticles and the photothermal properties of catechol microspheres, the composite hydrogel exhibited excellent anti-infection function, significantly downregulated inflammatory factors (TNF-α and IL-1ß) and promoted in vivo infected-wound healing. These results demonstrated that the polysaccharide hydrogel containing Ag@CFRs has great potential for infected-wounds repair.


Assuntos
Quitosana , Nanopartículas Metálicas , Hidrogéis/farmacologia , Prata , Escherichia coli , Microesferas , Staphylococcus aureus , Antibacterianos/farmacologia , Catecóis/farmacologia , Anti-Inflamatórios , Polissacarídeos/farmacologia
11.
Opt Express ; 32(4): 6531-6539, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439353

RESUMO

Graphene oxide (GO) flat lens has a thickness in nanoscale. They modulates the light field via both phase and amplitude modulation and hence possess excellent focusing property. In this paper, we develop a systematic design method to realize the ultrathin GO flat lens with various focusing properties. By using the Rayleigh-Sommerfield theory, the focusing property of ultrathin GO lenses is accurately calculated, then the genetic algorithm (GA) is employed to design the GO lenses. The lens works at visible frequency can have a large radius and long working distance. By setting different optimization objectives, extraordinary focusing property including sub-diffraction limit focusing with FWHM (∼1.96λ) and achromatic focusing with the wavelengths (450 nm, 550 nm, 650 nm) can be achieved. These innovative designs are fabricated and tested.

12.
Small ; : e2400615, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477702

RESUMO

Despite the intriguing potential, nano-socketed Cu/perovskite heterostructures for CO2 electroreduction (CO2 RR) are still in their infancy and rational optimization of their CO2 RR properties is lacking. Here, an effective strategy is reported to promote CO2 -to-C2+ conversion over nano-socketed Cu/perovskite heterostructures by A-site-valence-controlled oxygen vacancies. For the proof-of-concept catalysts of Cu/La0.3-x Sr0.6+x TiO3-δ (x from 0 to 0.3), their oxygen vacancy concentrations increase controllably with the decreased A-site valences (or the increased x values). In flow cells, their activity and selectivity for C2+ present positive correlations with the oxygen vacancy concentrations. Among them, the Cu/Sr0.9 TiO3-δ with most oxygen vacancies shows the optimal activity and selectivity for C2+ . And relative to the Cu/La0.3 Sr0.6 TiO3-δ with minimum oxygen vacancies, the Cu/Sr0.9 TiO3-δ exhibits marked improvements (up to 2.4 folds) in activity and selectivity for C2+ . The experiments and theoretical calculations suggest that the optimized performance can be attributed to the merits provided by oxygen vacancies, including the accelerated charge transfer, enhanced adsorption/activation of reaction species, and reduced energy barrier for C─C coupling. Moreover, when explored in a membrane-electrode assembly electrolyzer, the Cu/Sr0.9 TiO3-δ catalyst shows excellent activity, selectivity (43.9%), and stability for C2 H4 at industrial current densities, being the most effective perovskite-based catalyst for CO2 -to-C2 H4 conversion.

13.
Angew Chem Int Ed Engl ; 63(16): e202401570, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38380578

RESUMO

1,2-migration is one recurring isomerization reaction in organic chemistry. In contrast, double 1,2-migration remains rare and limited to transition-metal complexes. Herein, we describe the synthesis, characterization and reactivity of mixed heavier Sn=Ge vinylidenes. Double 1,2-carbon migration enables the isomerization of the stannagermenylidene (3) to the germastannenylidene (4). X-ray diffraction analysis and DFT calculations revealed that 3 and 4 feature a Sn=Ge double bond. The reaction of 3 with IMe4 (1,3,4,5-tetramethylimidazoline-2-ylidene) results in the electron redistribution in the Sn=Ge core to give the germylone-stannylene adduct (5). Moreover, treatment of 3 with 0.25 equiv. of (AlCp*)4 produces the heteronuclear aluminyl stannagermyne (6).

14.
bioRxiv ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38328181

RESUMO

Probing how the human neural networks operate is hindered by the lack of reliable human neural tissues amenable for dynamic functional assessment of neural circuits. We developed a 3D bioprinting platform to assemble tissues with defined human neural cell types in a desired dimension using a commercial bioprinter. The printed neuronal progenitors differentiate to neurons and form functional neural circuits in and between tissue layers with specificity within weeks, evidenced by the cortical-to-striatal projection, spontaneous synaptic currents and synaptic response to neuronal excitation. Printed astrocyte progenitors develop into mature astrocytes with elaborated processes and form functional neuron-astrocyte networks, indicated by calcium flux and glutamate uptake in response to neuronal excitation under physiological and pathological conditions. These designed human neural tissues will likely be useful for understanding the wiring of human neural networks, modeling pathological processes, and serving as platforms for drug testing.

15.
Cell Stem Cell ; 31(2): 260-274.e7, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306994

RESUMO

Probing how human neural networks operate is hindered by the lack of reliable human neural tissues amenable to the dynamic functional assessment of neural circuits. We developed a 3D bioprinting platform to assemble tissues with defined human neural cell types in a desired dimension using a commercial bioprinter. The printed neuronal progenitors differentiate into neurons and form functional neural circuits within and between tissue layers with specificity within weeks, evidenced by the cortical-to-striatal projection, spontaneous synaptic currents, and synaptic response to neuronal excitation. Printed astrocyte progenitors develop into mature astrocytes with elaborated processes and form functional neuron-astrocyte networks, indicated by calcium flux and glutamate uptake in response to neuronal excitation under physiological and pathological conditions. These designed human neural tissues will likely be useful for understanding the wiring of human neural networks, modeling pathological processes, and serving as platforms for drug testing.


Assuntos
Bioimpressão , Tecido Nervoso , Humanos , Neurônios/metabolismo , Astrócitos/metabolismo , Engenharia Tecidual
16.
Front Psychol ; 15: 1294982, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333062

RESUMO

Background: Postdoctoral researchers are critical to scholarly advancements, and promoting postdoctoral career growth is an endogenous path to help postdocs break through the "encircled city of scientific research". However, further research is needed to fully explore the mechanisms that connect workplace support to postdoctoral career growth. Methods: Drawing from the Conservation of Resources theory, this study proposes a chain mediation model that demonstrates how workplace support enhances career growth by connecting psychological capital with work-life balance. To understand the motivation and career growth of postdocs in China, we conducted two questionnaires in 2021 and 2023 with the support of relevant stations. Results: Analyzing 367 questionnaires from Chinese postdocs, our research indicates that workplace support has a positive impact on career growth. Additionally, both psychological capital and work-life balance are key factors that contribute to career growth, serving as separate mediators and as part of a chain of mediators. Discussion: This study validates the appropriateness of the Conservation of Resources theory in the study of the influence mechanism of postdoctoral career growth and proposes targeted strategies for academic institutions to improve support systems, promoting more effective career development pathways.

17.
Nat Commun ; 15(1): 1806, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418450

RESUMO

AcrIIA15 is an anti-CRISPR (Acr) protein that inhibits Staphylococcus aureus Cas9 (SaCas9). Although previous studies suggested it has dual functions, the structural and biochemical basis for its two activities remains unclear. Here, we determined the cryo-EM structure of AcrIIA15 in complex with SaCas9-sgRNA to reveal the inhibitory mechanism of the Acr's C-terminal domain (CTD) in mimicking dsDNA to block protospacer adjacent motif (PAM) recognition. For the N-terminal domain (NTD), our crystal structures of the AcrIIA15-promoter DNA show that AcrIIA15 dimerizes through its NTD to recognize double-stranded (ds) DNA. Further, AcrIIA15 can simultaneously bind to both SaCas9-sgRNA and promoter DNA, creating a supercomplex of two Cas9s bound to two CTDs converging on a dimer of the NTD bound to a dsDNA. These findings shed light on AcrIIA15's inhibitory mechanisms and its autoregulation of transcription, enhancing our understanding of phage-host interactions and CRISPR defense.


Assuntos
Bacteriófagos , Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , DNA/metabolismo , Staphylococcus aureus/genética , Bacteriófagos/genética , Bacteriófagos/metabolismo
18.
Aging (Albany NY) ; 16(2): 1128-1144, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38231482

RESUMO

BACKGROUND: Early life stress can cause cognitive impairment in aged offspring. Environmental enrichment (EE) is considered to be an effective non-pharmacological treatment for improving cognitive decline. The aim of this research was to evaluate the effect of EE, on cognitive impairment in aged offspring induced by maternal sleep deprivation (MSD) and the underlying mechanisms involved to investigate its potential value in clinical practice. METHODS: CD-1 damns were subjected or not to sleep deprivation during late gestation. Twenty-one days after birth, the offspring were assigned to standard or EE cages. At 18 months-old, the learning and memory function of the offspring mice was evaluated using Morris water maze. The hippocampal and prefrontal cortical levels of protein, gene, proinflammation cytokines, and oxidative stress indicators was examined by Western blot, real-time polymerase chain reaction, enzyme linked immunosorbent assay, and biochemical assays. RESULTS: Offspring in MSD group exhibited declined learning and memory abilities compared with control animals. Moreover, the hippocampal and prefrontal cortical levels of Sirtuin1 (Sirt1), peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α), postsynaptic density protein-95, and synaptophysin were lower and those of proinflammation cytokines higher in the MSD group; meanwhile, the superoxide dismutase content was higher and the malondialdehyde and reactive oxygen species contents were lower. However, these deleterious changes were ameliorated by exposure to EE. CONCLUSIONS: EE attenuates MSD-induced cognitive impairment, oxidative stress, and neuroinflammation and reverses the reduction in synaptic protein levels in aged offspring mice via the Sirt1/PGC-1α pathway.


Assuntos
Disfunção Cognitiva , Privação do Sono , Camundongos , Animais , Gravidez , Feminino , Privação do Sono/complicações , Privação do Sono/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Disfunção Cognitiva/metabolismo , Mitocôndrias/metabolismo , Citocinas/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo
19.
Mol Biol Evol ; 41(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38174583

RESUMO

Bioluminescence in beetles has long fascinated biologists, with diverse applications in biotechnology. To date, however, our understanding of its evolutionary origin and functional variation mechanisms remains poor. To address these questions, we obtained high-quality reference genomes of luminous and nonluminous beetles in 6 Elateroidea families. We then reconstructed a robust phylogenetic relationship for all luminous families and related nonluminous families. Comparative genomic analyses and biochemical functional experiments suggested that gene evolution within Elateroidea played a crucial role in the origin of bioluminescence, with multiple parallel origins observed in the luminous beetle families. While most luciferase-like proteins exhibited a conserved nonluminous amino acid pattern (TLA346 to 348) in the luciferin-binding sites, luciferases in the different luminous beetle families showed divergent luminous patterns at these sites (TSA/CCA/CSA/LVA). Comparisons of the structural and enzymatic properties of ancestral, extant, and site-directed mutant luciferases further reinforced the important role of these sites in the trade-off between acyl-CoA synthetase and luciferase activities. Furthermore, the evolution of bioluminescent color demonstrated a tendency toward hypsochromic shifts and variations among the luminous families. Taken together, our results revealed multiple parallel origins of bioluminescence and functional divergence within the beetle bioluminescent system.


Assuntos
Besouros , Animais , Humanos , Besouros/genética , Filogenia , Sequência de Aminoácidos , Luciferases/genética , Luciferases/química , Luciferases/metabolismo , Sítios de Ligação
20.
Environ Pollut ; 344: 123305, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38195022

RESUMO

Iron sludge, produced during the drinking water treatment process, can be recycled as potential iron resource to create environmental functional material. In this study, sulfur-iron composites derived from iron sludge (S-Fe composites) was synthesized through sulfidation and carbonization, and used for the tetracycline (TC) removal under aerobic and anoxic conditions. The reactivities of these as-prepared products were strongly depended on pyrolysis temperatures. In particular, sulfidated nanoscale zero-valent iron loaded on carbon (S-nFe0@CIS) carbonized at 800 °C exhibited the highest TC removal efficiency with 86.6% within 30 min at circumneutral pH compared with other S-Fe composites. The crystalline structure of α-Fe0, FeSx and S0 as main active sites in S-nFe0@CIS promoted the degradation of TC. Moreover, the Fe/S molar ratios significantly affected the TC removal rates, which reached the best value as the optimal S/Fe of 0.27. The results illustrated that the optimized extent of sulfidation could facilitate electron transfer from nFe0 towards contaminants and accelerate Fe(III)/Fe(II) cycle in reaction system compared to bared nFe0@CIS. We revealed that removal of TC by S-nFe0@CIS in the presence of dissolved oxygen (DO) is mainly attributed to oxidation, adsorption and reduction pathways. Their contribution to TC removal were 31.6%, 25.2% and 28.8%, respectively. Furthermore, this adsorption-oxygenation with the formation of S-nFe0@CIS-TC* complexes was a surface-mediated process, in which DO was transformed by the structural FeSx on complex surface to •OH with the generation of H2O2 intermediate. The intermediates of TC and toxicity analysis indicate that less toxicity products generated through degradation process. This study provides a new reclamation of iron sludge and offers a new insight into the TC removal by S-nFe0@CIS under aerobic conditions.


Assuntos
Esgotos , Poluentes Químicos da Água , Ferro/química , Peróxido de Hidrogênio , Tetraciclina/química , Antibacterianos/química , Oxigênio , Poluentes Químicos da Água/análise
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