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1.
Small ; : e2400410, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721986

RESUMO

The construction of defective sites is one of the effective strategies to create high-activity Metal-Organic frameworks (MOFs) catalysts. However, traditional synthesis methods usually suffer from cumbersome synthesis steps and disordered defect structures. Herein, a cluster-cluster co-nucleation (CCCN) strategy is presented that involves the in situ introduction of size-matched functional polyoxometalates (H6P2W18O62, {P2W18}) to intervene the nucleation process of cluster-based MOFs (UiO-66), achieving one-step inducement of exposed defective sites without redundant post-processing. POM-induced UiO-66 ({P2W18}-0.1@UiO-66) exhibits a classical reo topology for well-defined cluster defects. Moreover, the defective sites and the interaction between POM and skeletal cluster nodes are directly observed by Integrated Differential Phase Contrast in Scanning Transmission Electron Microscopy (iDPC-STEM). Owing to the molecular-level proximity between defective sites and POM in the same nano-reaction space, {P2W18}-0.1@UiO-66 exhibits efficient tandem catalysis in the preparation of γ-valerolactone (γ-GVL) from laevulinic acid (LA) by the combination of Lewis and Brønsted acids with 11 times higher performance than defective UiO-66 formed by conventional coordination modulation strategy. The CCCN strategy is applicable to different POM and has the potential to be extended to other cluster-based MOFs, which will pave a new way for the construction of functional MOFs with multi-centered synergistic catalysis.

2.
Mol Biotechnol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748071

RESUMO

Langerhans cell histiocytosis (LCH) is a rare condition predominantly affecting young children. Activation of the MAPK pathway has offered key new insights into the pathogenesis of LCH; however, the precise mechanisms underlying its occurrence and development are still far from being completely elucidated. There is still a relapse/reactivation rate in patients with multisystem LCH. Therefore, this study aimed to investigate other potential LCH pathophysiologies and prospective therapeutic targets. The gene expression omnibus (GEO) database was used to retrieve gene expression profiles of LCH (GSE16395). Three distinct types of analyses were performed after identifying the common differentially expressed genes (DEGs) in LCH: hub gene identification, functional annotation, module construction, drug repositioning, and expression analysis via immunohistochemistry (IHC). We identified 417 common DEGs and 50 central hub genes. This functional study highlighted the significance of keratinization, skin development, and inflammation. In addition, we predicted new drug candidates (RS2 drugs targeting matrix metalloprotease1, MMP1) that could be used for LCH treatment. Finally, gene-miRNA and gene-TF networks and immune cell infiltration were analyzed for MMP1-related genes. MMP1 expression levels in LCH tissues were validated by IHC. Our study identified the central communal genes and novel drug candidates. These shared pathways and hub genes offer new perspectives on future mechanisms of action and therapeutic targets.

4.
Med Eng Phys ; 127: 104158, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692761

RESUMO

BACKGROUND: The intervertebral disc exhibits not only strain rate dependence (viscoelasticity), but also significant asymmetry under tensile and compressive loads, which is of great significance for understanding the mechanism of lumbar disc injury under physiological loads. OBJECTIVE: In this study, the strain rate sensitive and tension-compression asymmetry of the intervertebral disc were analyzed by experiments and constitutive equation. METHOD: The Sheep intervertebral disc samples were divided into three groups, in order to test the strain rate sensitive mechanical behavior, and the internal displacement as well as pressure distribution. RESULTS: The tensile stiffness is one order of magnitude smaller than the compression stiffness, and the logarithm of the elastic modulus is approximately linear with the logarithm of the strain rate, showing obvious tension-compression asymmetry and rate-related characteristics. In addition, the sensitivity to the strain rate is the same under these two loading conditions. The stress-strain curves of unloading and loading usually do not coincide, and form a Mullins effect hysteresis loop. The radial displacement distribution is opposite between the anterior and posterior region, which is consistent with the stress distribution. By introducing the damage factor into ZWT constitutive equation, the rate-dependent viscoelastic and weakening behavior of the intervertebral disc can be well described.


Assuntos
Força Compressiva , Disco Intervertebral , Estresse Mecânico , Animais , Disco Intervertebral/fisiologia , Ovinos , Fenômenos Biomecânicos , Resistência à Tração , Suporte de Carga , Elasticidade
5.
Inorg Chem ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753036

RESUMO

Heterogeneous palladium catalysts with high efficiency, high Pd atom utilization, simplified separation, and recycle have attracted considerable attention in the field of synthetic chemistry. Herein, we reported a zirconium-based two-dimensional metal-organic framework (2D-MOF)-based Pd(II) photocatalyst (Zr-Ir-Pd) by merging the Ir photosensitizers and Pd(II) species into the skeletons of the 2D-MOF for the Pd(II)-catalyzed oxidation reaction. Morphological and structural characterization identified that Zr-Ir-Pd with a specific nanoflower-like structure consists of ultrathin 2D-MOF nanosheets (3.85 nm). Due to its excellent visible-light response and absorption capability, faster transfer and separation of photogenerated carriers, more accessible Pd active sites, and low mass transfer resistance, Zr-Ir-Pd exhibited boosted photocatalytic activity in catalyzing sterically hindered isocyanide insertion of diarylalkynes for the construction of fused tetracyclic heterocycles, with up to 12 times the Pd catalyst turnover number than the existing catalytic systems. In addition, Zr-Ir-Pd inhibited the competitive agglomeration of Pd(0) species and could be reused at least five times, owing to the stabilization of 2D-MOF on the single-site Pd and Ir sites. Finally, a possible mechanism of the photocatalytic synthesis of fused tetracyclic heterocycles catalyzed by Zr-Ir-Pd was proposed.

6.
Nat Commun ; 15(1): 4300, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773134

RESUMO

The chromatin modifier GRAIN WEIGHT 6a (GW6a) enhances rice grain size and yield. However, little is known about its gene network determining grain size. Here, we report that MITOGEN-ACTIVED PROTEIN KINASE 6 (OsMAPK6) and E3 ligase CHANG LI GENG 1 (CLG1) interact with and target GW6a for phosphorylation and ubiquitylation, respectively. Unexpectedly, however, in vitro and in vivo assays reveal that both of the two post-translational modifications stabilize GW6a. Furthermore, we uncover two major GW6a phosphorylation sites (serine142 and threonine186) targeted by OsMAPK6 serving an important role in modulating grain size. In addition, our genetic and molecular results suggest that the OsMAPK6-GW6a and CLG1-GW6a axes are crucial and operate in a non-additive manner to control grain size. Overall, our findings identify a previously unknown mechanism by which phosphorylation and ubiquitylation non-additively stabilize GW6a to enhance grain size, and reveal correlations and interactions of these posttranslational modifications during rice grain development.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Ubiquitinação , Oryza/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Fosforilação , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Grão Comestível/metabolismo , Grão Comestível/crescimento & desenvolvimento , Processamento de Proteína Pós-Traducional , Plantas Geneticamente Modificadas , Cromatina/metabolismo
7.
Med Phys ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558279

RESUMO

BACKGROUND: Cushing's Disease (CD) is a rare clinical syndrome characterized by excessive secretion of adrenocorticotrophic hormone, leading to significant functional and structural brain alterations as observed in Magnetic Resonance Imaging (MRI). While traditional statistical analysis has been widely employed to investigate these MRI changes in CD, it has lacked the ability to predict individual-level outcomes. PURPOSE: To address this problem, this paper has proposed an interpretable machine learning (ML) framework, including model-level assessment, feature-level assessment, and biology-level assessment to ensure a comprehensive analysis based on structural MRI of CD. METHODS: The ML framework has effectively identified the changes in brain regions in the stage of model-level assessment, verified the effectiveness of these altered brain regions to predict CD from normal controls in the stage of feature-level assessment, and carried out a correlation analysis between altered brain regions and clinical symptoms in the stage of biology-level assessment. RESULTS: The experimental results of this study have demonstrated that the Insula, Fusiform gyrus, Superior frontal gyrus, Precuneus, and the opercular portion of the Inferior frontal gyrus of CD showed significant alterations in brain regions. Furthermore, our study has revealed significant correlations between clinical symptoms and the frontotemporal lobes, insulin, and olfactory cortex, which also have been confirmed by previous studies. CONCLUSIONS: The ML framework proposed in this study exhibits exceptional potential in uncovering the intricate pathophysiological mechanisms underlying CD, with potential applicability in diagnosing other diseases.

8.
Acta Pharmacol Sin ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589689

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is closely associated with metabolic derangement. Sodium glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) exert anti-HFpEF effects, but the underlying mechanisms remain unclear. In this study, we explored the anti-HFpEF effects of empagliflozin and liraglutide and the underlying molecular mechanisms in a mouse model of HFpEF. This model was established by high-fat diet (HFD) feeding plus Nω-nitro-L-arginine methyl ester (L-NAME) treatment. The mice were treated with empagliflozin (20 mg·kg-1·d-1, i.g.) or liraglutide (0.3 mg·kg-1·d-1, i.p.) or their combination for 4 weeks. At the end of the experimental protocol, cardiac function was measured using ultrasound, then mice were euthanized and heart, liver, and kidney tissues were collected. Nuclei were isolated from frozen mouse ventricular tissue for single-nucleus RNA-sequencing (snRNA-seq). We showed that administration of empagliflozin or liraglutide alone or in combination significantly improved diastolic function, ameliorated cardiomyocyte hypertrophy and cardiac fibrosis, as well as exercise tolerance but no synergism was observed in the combination group. Furthermore, empagliflozin and/or liraglutide lowered body weight, improved glucose metabolism, lowered blood pressure, and improved liver and kidney function. After the withdrawal of empagliflozin or liraglutide for 1 week, these beneficial effects tended to diminish. The snRNA-seq analysis revealed a subcluster of myocytes, in which Erbb4 expression was down-regulated under HFpEF conditions, and restored by empagliflozin or liraglutide. Pseudo-time trajectory analysis and cell-to-cell communication studies confirmed that the Erbb4 pathway was a prominent pathway essential for both drug actions. In the HFpEF mouse model, both empagliflozin and liraglutide reversed Erbb4 down-regulation. In rat h9c2 cells, we showed that palmitic acid- or high glucose-induced changes in PKCα and/or ERK1/2 phosphorylation at least in part through Erbb4. Collectively, the single-cell atlas reveals the anti-HFpEF mechanism of empagliflozin and liraglutide, suggesting that Erbb4 pathway represents a new therapeutic target for HFpEF. Effects and mechanisms of action of empagliflozin and liraglutide in HFpEF mice. HFpEF was induced with a high-fat diet and L-NAME for 15 weeks, and treatment with empagliflozin and liraglutide improved the HFpEF phenotype. Single nucleus RNA sequencing (snRNA-seq) was used to reveal the underlying mechanism of action of empagliflozin and liraglutide.

9.
J Autism Dev Disord ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607473

RESUMO

PURPOSE: This study aimed to explore the effect of family-professional partnerships in adapted physical education on the fundamental motor skills, physical activity levels, and adaptive behaviors of children with autism spectrum disorder (ASD) and on parental satisfaction. METHODS: A randomized controlled trial design was used, with pre-and post-intervention evaluations. Participants (n = 40), including children with ASD and their parents, were divided into three groups: (a) a family-school group (FSG-A, n = 14), (b) a school group (SG-B, n = 13), and (c) a control group (CG-C, n = 13). RESULTS: After 12 weeks of intervention, the within-group comparison revealed that the FSG-A performed better than the SG-B and CG-C for all variables. The among-group comparison further revealed that the FSG-A had greater fundamental motor skill scores than the SG-B (p = 0.021) and CG-C (p < 0.001), had greater adaptive behavior and family-professional partnership scores than the SG-B and CG-C (p < 0.001 for all), and had higher physical activity levels than the SG-B (p < 0.05) and CG-C (p < 0.001). CONCLUSION: This study underscores the significance of robust family-professional partnerships in exercise interventions for children with ASD.

10.
Bio Protoc ; 14(7): e4966, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38618175

RESUMO

Contractile injection systems (CISs), one of the most important bacterial secretion systems that transport substrates across the membrane, are a collection of diverse but evolutionarily related macromolecular devices. Numerous effector proteins can be loaded and injected by this secretion complex to their specific destinations. One group of CISs called extracellular CIS (eCIS) has been proposed as secretory molecules that can be released from the bacterial cytoplasm and attack neighboring target cells from the extracellular environment. This makes them a potential delivery vector for the transportation of various cargos without the inclusion of bacterial cells, which might elicit certain immunological responses from hosts. We have demonstrated that the Photorhabdus virulence cassette (PVC), which is a typical eCIS, could be applied as an ideal vector for the translocation of proteinaceous cargos with different physical or chemical properties. Here, we describe the in-depth purification protocol of this mega complex from Escherichia coli. The protocol provided is a simpler, faster, and more productive way of generating the eCIS complexes than available methodologies reported previously, which can facilitate the subsequent applications of these nanodevices and other eCIS in different backgrounds.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38597328

RESUMO

Species are distributed in predictable ways in geographic spaces. The three principal factors that determine geographic distributions of species are biotic interactions (B), abiotic conditions (A), and dispersal ability or mobility (M). A species is expected to be present in areas that are accessible to it and that contain suitable sets of abiotic and biotic conditions for it to persist. A species' probability of presence can be quantified as a combination of responses to B, A, and M via ecological niche modeling (ENM; also frequently referred to as species distribution modeling or SDM). This analytical approach has been used broadly in ecology and biogeography, as well as in conservation planning and decision-making, but commonly in the context of 'natural' settings. However, it is increasingly recognized that human impacts, including changes in climate, land cover, and ecosystem function, greatly influence species' geographic ranges. In this light, historical distinctions between natural and anthropogenic factors have become blurred, and a coupled human-natural landscape is recognized as the new norm. Therefore, B, A, and M (BAM) factors need to be reconsidered to understand and quantify species' distributions in a world with a pervasive signature of human impacts. Here, we present a framework, termed human-influenced BAM (Hi-BAM, for distributional ecology that (i) conceptualizes human impacts in the form of six drivers, and (ii) synthesizes previous studies to show how each driver modifies the natural BAM and species' distributions. Given the importance and prevalence of human impacts on species distributions globally, we also discuss implications of this framework for ENM/SDM methods, and explore strategies by which to incorporate increasing human impacts in the methodology. Human impacts are redefining biogeographic patterns; as such, future studies should incorporate signals of human impacts integrally in modeling and forecasting species' distributions.

12.
J Med Virol ; 96(5): e29627, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38659381

RESUMO

The immune mechanism underlying hepatitis B surface antigen (HBsAg) loss, particularly type I inflammatory response, during pegylated interferon-α (PEG-IFN) therapy remains unclear. In this study, we aimed to elucidate such immune mechanisms. Overall, 82 patients with chronic hepatitis B (CHB), including 41 with HBsAg loss (cured group) and 41 uncured patients, received nucleos(t)ide analogue and PEG-IFN treatments. Blood samples from all patients, liver tissues from 14 patients with CHB, and hepatic perfusate from 8 liver donors were collected for immune analysis. Jurkat, THP-1 and HepG2.2.15 cell lines were used in cell experiments. The proportion of IFN-γ+ Th1 cells was higher in the cured group than in the uncured group, which was linearly correlated with HBsAg decline and alanine aminotransferase (ALT) levels during treatment. However, CD8+ T cells were weakly associated with HBsAg loss. Serum and intrahepatic levels of Th1 cell-associated chemokines (C-X-C motif chemokine ligand [CXCL] 9, CXCL10, CXCL11, IFN-γ) were significantly lower in the cured patients than in patients with a higher HBsAg quantification during therapy. Serum from cured patients induced more M1 (CD68+CD86+ macrophage) cells than that from uncured patients. Patients with chronic HBV infection had significantly lower proportions of CD86+ M1 and CD206+ M2 macrophages in their livers than healthy controls. M1 polarization of intrahepatic Kupffer cells promoted HBsAg loss by upregulating the effector function of tissue-resident memory T cells with increased ALT levels. IFN-γ+ Th1 activates intrahepatic resident memory T cells to promote HBsAg loss by inducing M1 macrophage polarization.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Fígado , Macrófagos , Células T de Memória , Células Th1 , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antivirais/uso terapêutico , Antivirais/farmacologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa , Interferon gama , Fígado/imunologia , Macrófagos/imunologia , Células T de Memória/imunologia , Células Th1/imunologia
13.
World J Clin Cases ; 12(11): 1980-1989, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38660556

RESUMO

BACKGROUND: This case report presents the rare occurrence of hematochezia due to an internal iliac artery aneurysm leading to an arterioenteric fistula, expanding the differential diagnosis for gastrointestinal bleeding. It emphasizes the importance of considering vascular origins in cases of atypical hematochezia, particularly in the absence of common gastrointestinal causes, and highlights the role of imaging and multidisciplinary management in diagnosing and treating such unusual presentations. CASE SUMMARY: A 75-year-old man with a history of hypertension presented with 12 d of hematochezia, experiencing bloody stools 7-8 times per day. Initial computed tomography (CT) scans revealed an aneurysmal rupture near the right internal iliac artery with suspected hematoma development. Hemoglobin levels progressively decreased to 7 g/dL. Emergency arterial angiography and iliac artery-covered stent placement were performed, followed by balloon angioplasty. Despite initial stabilization, minor rectal bleeding and abdominal pain persisted, leading to further diagnostic colonoscopy. This identified a neoplasm and potential perforation at the proximal rectum. An exploratory laparotomy confirmed the presence of a hematoma and an aneurysm invading the rectal wall, necessitating partial rectal resection, intestinal anastomosis, and ileostomy. Postoperative recovery was successful, with no further bleeding incidents and normal follow-up CT and colonoscopy results after six months. CONCLUSION: In cases of unusual gastrointestinal bleeding, it is necessary to consider vascular causes for effective diagnosis and intervention.

15.
Nano Lett ; 24(15): 4658-4664, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38563608

RESUMO

Planar Josephson junctions are predicted to host Majorana zero modes. The material platforms in previous studies are two-dimensional electron gases (InAs, InSb, InAsSb, and HgTe) coupled to a superconductor such as Al or Nb. Here, we introduce a new material platform for planar JJs, the PbTe-Pb hybrid. The semiconductor, PbTe, was grown as a thin film via selective area epitaxy. The Josephson junction was defined by a shadow wall during the deposition of superconductor Pb. Scanning transmission electron microscopy reveals a sharp semiconductor-superconductor interface. Gate-tunable supercurrents and multiple Andreev reflections are observed. A perpendicular magnetic field causes interference patterns of the switching current, exhibiting Fraunhofer-like and SQUID-like behaviors. We further demonstrate a prototype device for Majorana detection wherein phase bias and tunneling spectroscopy are applicable.

16.
Zhen Ci Yan Jiu ; 49(4): 391-397, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38649207

RESUMO

OBJECTIVES: To observe the effect of electroacupuncture (EA) at "Baihui" (GV20) and "Shenting" (GV24) on the rats' behavior and the transforming precursor of brain-derived neurotrophic factor (proBDNF) into mature brain-derived neurotrophic factor (mBDNF) in the hippocampus of rats with learning and memory impairment induced by cerebral ischemia-reperfusion (IR), so as to explore its mechanisms underlying improvement of learning and memory ability. METHODS: SD rats were randomly divided into blank, sham operation, model, and EA groups, with 6 rats in each group. The model of IR was established by occlusion of the middle cerebral artery. EA (1 Hz/20 Hz) was applied to GV24 and GV20 for 30 min, once daily for 14 days. The neurological function was evaluated according to the Zea Longa's score criteria 24 h after modeling and after intervention. Morris water maze test was used to detect the learning and memory function of the rats. TTC staining was used to evaluate the cerebral infarction volume on the affected side. The protein expression levels of proBDNF, mBDNF, tissue plasminogen activator (tPA), tyrosine kinase receptor B (TrkB) and p75 neurotrophin receptor (p75NTR) in hippocampal tissue were detected by Western blot. RESULTS: Compared with the sham operation group, the neurological function score, the percentage of cerebral infarction volume and the expression levels of proBDNF and p75NTR protein in hippocampus were increased (P<0.01), while the times of crossing the original platform and the total distance in the target quadrant, the expression levels of mBDNF, TrkB and tPA protein and the ratio of mBDNF/proBDNF were decreased (P<0.01, P<0.05) in the model group. Compared with the model group, the neurological function score, the percentage of cerebral infarction volume, and the expression levels of proBDNF and p75NTR protein in hippocampus were decreased (P<0.01, P<0.05), while the times of crossing the original platform, the total distance in the target quadrant, and the expression levels of mBDNF, TrkB and tPA protein and the ratio of mBDNF/proBDNF were increased (P<0.05, P<0.01) in the EA group. CONCLUSIONS: EA can alleviate learning and memory impairment in IR rats, which may be related to its function in up-regulating the expression of tPA protein and promoting the transformation of proBDNF to mBDNF, thus improving the synaptic plasticity.


Assuntos
Isquemia Encefálica , Fator Neurotrófico Derivado do Encéfalo , Eletroacupuntura , Transtornos da Memória , Plasticidade Neuronal , Precursores de Proteínas , Traumatismo por Reperfusão , Animais , Humanos , Masculino , Ratos , Pontos de Acupuntura , Isquemia Encefálica/metabolismo , Isquemia Encefálica/terapia , Isquemia Encefálica/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Hipocampo/metabolismo , Aprendizagem , Memória , Transtornos da Memória/terapia , Transtornos da Memória/metabolismo , Transtornos da Memória/etiologia , Ratos Sprague-Dawley , Receptor trkB/metabolismo , Receptor trkB/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/genética
17.
J Am Chem Soc ; 146(18): 12636-12644, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38676645

RESUMO

Orbital hybridization to regulate the electronic structures and surface chemisorption properties of transition metals is of great importance for boosting the oxygen reduction reaction (ORR) in proton-exchange membrane fuel cells (PEMFCs). Herein, we developed a core-shell rambutan-like nanocarbon catalyst (FeAl-RNC) with atomically dispersed Fe-Al atom pairs from metal-organic framework (MOF) material. Experimental and theoretical results demonstrate that the strong p-d orbital hybridization between Al and Fe results in an asymmetric electron distribution with moderate adsorption strength of oxygen intermediates, rendering enhanced intrinsic ORR activity. Additionally, the core-shell rambutan-like structure of FeAl-RNC with abundant micropores and macropores can enhance the density of active sites, stability, and transport pathways in PEMFC. The FeAl-RNC-based PEMFC achieves excellent activity (68.4 mA cm-2 at 0.9 V), high peak power (1.05 W cm-2), and good stability with only 7% current loss after 100 h at 0.7 V under H2-O2 condition.

18.
Phytochemistry ; 222: 114098, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38648960

RESUMO

Nine undescribed compounds, along with eight known compounds, were isolated from the stipes of Lentinus edodes. Their structures were established by extensive spectroscopic and circular dichroism analyses. The protective effects against Aß25-35-induced N9 microglia cells injury of these compounds were tested by MTT method, and the levels of apoptosis and ROS were detected by flow cytometry. In addition, the binding sites and interactions of compound with amyloid precursor protein were revealed using molecular docking simulations. These findings further establish the structural diversity and bioactivity of stipes of L. edodes, and provide an experimental basis for targeting Alzheimer's disease as a potential strategy.


Assuntos
Peptídeos beta-Amiloides , Apoptose , Microglia , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Fragmentos de Peptídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Camundongos , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Lentinula/química , Linhagem Celular
19.
Cell Commun Signal ; 22(1): 245, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671456

RESUMO

BACKGROUND: The alveolar epithelial type II cell (AT2) and its senescence play a pivotal role in alveolar damage and pulmonary fibrosis. Cell circadian rhythm is strongly associated with cell senescence. Differentiated embryonic chondrocyte expressed gene 1 (DEC1) is a very important circadian clock gene. However, the role of DEC1 in AT2 senescence and pulmonary fibrosis was still unclear. RESULTS: In this study, a circadian disruption model of light intervention was used. It was found that circadian disruption exacerbated pulmonary fibrosis in mice. To understand the underlying mechanism, DEC1 levels were investigated. Results showed that DEC1 levels increased in lung tissues of IPF patients and in bleomycin-induced mouse fibrotic lungs. In vitro study revealed that bleomycin and TGF-ß1 increased the expressions of DEC1, collagen-I, and fibronectin in AT2 cells. Inhibition of DEC1 mitigated bleomycin-induced fibrotic changes in vitro and in vivo. After that, cell senescence was observed in bleomycin-treated AT2 cells and mouse models, but these were prevented by DEC1 inhibition. At last, p21 was confirmed having circadian rhythm followed DEC1 in normal conditions. But bleomycin disrupted the circadian rhythm and increased DEC1 which promoted p21 expression, increased p21 mediated AT2 senescence and pulmonary fibrosis. CONCLUSIONS: Taken together, circadian clock protein DEC1 mediated pulmonary fibrosis via p21 and cell senescence in alveolar epithelial type II cells.


Assuntos
Bleomicina , Senescência Celular , Ritmo Circadiano , Fibrose Pulmonar , Animais , Humanos , Masculino , Camundongos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Ritmo Circadiano/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/patologia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
20.
Mol Biol Evol ; 41(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38507653

RESUMO

Although gene loss is common in evolution, it remains unclear whether it is an adaptive process. In a survey of seven major mangrove clades that are woody plants in the intertidal zones of daily environmental perturbations, we noticed that they generally evolved reduced gene numbers. We then focused on the largest clade of Rhizophoreae and observed the continual gene set reduction in each of the eight species. A great majority of gene losses are concentrated on environmental interaction processes, presumably to cope with the constant fluctuations in the tidal environments. Genes of the general processes for woody plants are largely retained. In particular, fewer gene losses are found in physiological traits such as viviparous seeds, high salinity, and high tannin content. Given the broad and continual genome reductions, we propose the May-Wigner theory (MWT) of system stability as a possible mechanism. In MWT, the most effective solution for buffering continual perturbations is to reduce the size of the system (or to weaken the total genic interactions). Mangroves are unique as immovable inhabitants of the compound environments in the land-sea interface, where environmental gradients (such as salinity) fluctuate constantly, often drastically. Extending MWT to gene regulatory network (GRN), computer simulations and transcriptome analyses support the stabilizing effects of smaller gene sets in mangroves vis-à-vis inland plants. In summary, we show the adaptive significance of gene losses in mangrove plants, including the specific role of promoting phenotype innovation and a general role in stabilizing GRN in unstable environments as predicted by MWT.


Assuntos
Redes Reguladoras de Genes , Genoma , Perfilação da Expressão Gênica , Plantas
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