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1.
Artigo em Inglês | MEDLINE | ID: mdl-39001888

RESUMO

PURPOSE: To examine the dose‒response relationships of sedentary behavior (SB) and physical activities (PAs) with depression, and to explore the effects of replacing SB with PAs on depression risk. METHODS: The study used data from UK Biobank aged 37 to 73 years. Light physical activity (LPA), moderate-to-vigorous activity (MVPA), sleep duration, and total sedentary behavior (TSB) were measured by accelerometers. Self-reported SB was also adopted when daily screen-sedentary behavior time (SSB) and leisure-sedentary behavior time (LSB) were the focus. Incident depression was obtained from the part of mental and behavioral disorders in the "first occurrence fields" of UK Biobank. A Cox proportional hazard model and isotemporal substitution model were performed to explore the associations of LPA, MVPA, TSB, LSB, SSB, and sleep on depression and the effects of replacing SB time with equal PA time. RESULTS: Highest levels of MVPA (HR = 0.58, 95%CI: 0.50-0.68) were associated with decreased depression risk compared with the lowest level (Q1). Longer SSB time (HR = 1.18, 95%CI: 1.06-1.32), LSB time (HR = 1.19, 95%CI: 1.07-1.32), and TSB time (HR = 1.17, 95%CI: 1.00-1.38) could increase depression risk significantly. Replacing 1h/day TSB, SSB, and LSB with MVPA brought the greatest risk reductions [31% (HR = 0.69, 95%CI: 0.62-0.77), 30% (HR = 0.70, 95%CI: 0.65-0.77), and 29% (HR = 0.71, 95%CI: 0.65-0.77)]. Under the same conditions, the effects of LPA replacement were also significant, but weaker than those of MVPA. Subgroup analyses showed that replacing 1h/d TSB with LPA could significantly decrease the depression risk for the females, but not for the males. CONCLUSION: Large benefits for reducing the risk of incident depression could be attained by replacing a period of TSB, SSB, or LSB with equal PA time, especially for MVPA. Regular PA and less SB were recommended for improving mental health.

2.
Cell Death Differ ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39009654

RESUMO

Dysregulated metabolism, cell death, and inflammation contribute to the development of metabolic dysfunction-associated steatohepatitis (MASH). Pyroptosis, a recently identified form of programmed cell death, is closely linked to inflammation. However, the precise role of pyroptosis, particularly gasdermin-E (GSDME), in MASH development remains unknown. In this study, we observed GSDME cleavage and GSDME-associated interleukin-1ß (IL-1ß)/IL-18 induction in liver tissues of MASH patients and MASH mouse models induced by a choline-deficient high-fat diet (CDHFD) or a high-fat/high-cholesterol diet (HFHC). Compared with wild-type mice, global GSDME knockout mice exhibited reduced liver steatosis, steatohepatitis, fibrosis, endoplasmic reticulum stress, lipotoxicity and mitochondrial dysfunction in CDHFD- or HFHC-induced MASH models. Moreover, GSDME knockout resulted in increased energy expenditure, inhibited intestinal nutrient absorption, and reduced body weight. In the mice with GSDME deficiency, reintroduction of GSDME in myeloid cells-rather than hepatocytes-mimicked the MASH pathologies and metabolic dysfunctions, as well as the changes in the formation of neutrophil extracellular traps and hepatic macrophage/monocyte subclusters. These subclusters included shifts in Tim4+ or CD163+ resident Kupffer cells, Ly6Chi pro-inflammatory monocytes, and Ly6CloCCR2loCX3CR1hi patrolling monocytes. Integrated analyses of RNA sequencing and quantitative proteomics revealed a significant GSDME-dependent reduction in citrullination at the arginine-114 (R114) site of dynamin-related protein 1 (Drp1) during MASH. Mutation of Drp1 at R114 reduced its stability, impaired its ability to redistribute to mitochondria and regulate mitophagy, and ultimately promoted its degradation under MASH stress. GSDME deficiency reversed the de-citrullination of Drp1R114, preserved Drp1 stability, and enhanced mitochondrial function. Our study highlights the role of GSDME in promoting MASH through regulating pyroptosis, Drp1 citrullination-dependent mitochondrial function, and energy balance in the intestine and liver, and suggests that GSDME may be a potential therapeutic target for managing MASH.

3.
Imeta ; 3(2): e179, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38882498

RESUMO

The administration of oral antidiabetic drugs (OADs) to patients with type 2 diabetes elicits distinct and shared changes in the gut microbiota, with acarbose and berberine exhibiting greater impacts on the gut microbiota than metformin, vildagliptin, and glipizide. The baseline gut microbiota strongly associates with treatment responses of OADs.

4.
Polymers (Basel) ; 16(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38932074

RESUMO

The purpose of this study is to prepare monodisperse silica mesoporous microspheres with narrow pore size distribution to promote their application in the field of liquid chromatography. An improved emulsion method was used to prepare silica mesoporous microspheres, and the rotary evaporation temperature, emulsification speed, dosage of porogen DMF, and dosage of the catalyst NH3·H2O were optimized. Subsequently, these microspheres were respectively treated by alkali-heating, calcination, and sieving. The D50 (particle size at the cumulative particle size distribution percentage of 50%) of as-prepared silica mesoporous microspheres is 26.3 µm, and the D90/D10 (the ratio of particle size at a cumulative particle size distribution percentage of 90% to a cumulative particle size distribution percentage of 10%) is 1.94. The resultant silica mesoporous microspheres have distinctive pore structures, with a pore volume of more than 1.0 cm3/g, an average pore size of 11.35 nm, and a median pore size of 13.4 nm. The silica mesoporous microspheres with a large particle size, uniform particle size distribution, large average pore size and pore volume, and narrow mesopore size distribution can basically meet the requirements of preparative liquid chromatographic columns.

5.
Ultrason Sonochem ; 107: 106931, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823084

RESUMO

Thawing is the primary step in handling frozen aquatic products, which directly determines their end-product quality. This study firstly constructed a novel thawing method of ultrasound-assisted slightly basic electrolyzed water (UST), and its influences on the physicochemical and histological properties of shrimp, as well as the structural of myofibrillar proteins (MPs) in shrimp were evaluated. Results indicated that the UST treatment greatly reduced 48.9 % thawing time of frozen shrimp compared to traditional thawing approaches. Meanwhile, the UST effectively decreased the generation of malondialdehyde (MDA), total volatile basic nitrogen (TVB-N), and carbonyl compounds in the thawed shrimps. In addition, it significantly preserved the elasticity and integrity of muscle fiber. Notably, the UST reduced the damage of thawing to the spatial structures of MPs, thereby greatly keeping the stability of protein. All these favorable changes maintained the water holding capacity (WHC) and quality of shrimp. Therefore, the UST is a promising non-thermal thawing technology for aquatic products.


Assuntos
Congelamento , Penaeidae , Água , Animais , Água/química , Penaeidae/química , Ondas Ultrassônicas , Eletrólise/métodos , Malondialdeído , Manipulação de Alimentos/métodos
6.
Sci Total Environ ; 942: 173755, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38851336

RESUMO

In order to realize the low-carbon development policy, the large-scale development and utilization of nuclear energy is very essential. Uranium is the key resource for nuclear industry. The extracting and recycling uranium from seawater and nuclear wastewater is necessary for secure uranium reserves, ensure energy security, control pollution and protect the environment. The novel nanomaterial MXene possesses the layered structure, high specific surface area, and modifiable surface terminal groups, which allowed it to enrich uranium. In addition, good photovoltaic and photothermal properties improves the ability to adsorb uranium. The excellent radiation resistance of the MAX phase strongly indicates the potential use of MXene as an effective uranium adsorbent. However, there are relatively few reviews on its application in uranium extraction and recovery. This review focuses on the recent advances in the use of MXene-based materials as highly efficient adsorbents for the recovery of uranium from seawater and nuclear wastewater. First, the structural, synthetic and characterization aspects of MXene materials are introduced. Subsequently, the adsorptive properties of MXene-based materials are evaluated in terms of uranium extraction recovery capability, selectivity, and reproducibility. Furthermore, the interaction mechanisms between uranium and MXene absorbers are discussed. Finally, the challenges for MXene materials in uranium adsorption applications are proposed for better design of new types of MXene-based adsorbents.

7.
J Colloid Interface Sci ; 670: 223-233, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761575

RESUMO

Macrophages can kill bacteria and viruses by releasing free radicals, which provides a possible approach to construct antifouling coatings with dynamic surfaces that release free radicals if the breaking of dynamic covalent bonds is precisely regulated. Herein, inspired by the defensive behavior of macrophages of releasing free radicals to kill bacteria and viruses, a marine antifouling coating composed of polyurethane incorporating dimethylglyoxime (PUx-DMG) is prepared by precise regulation of dynamic oxime-urethane covalent bonds. The obtained alkyl radical (R·) derived from the cleavage of the oxime-urethane bonds manages to effectively suppress the attachment of marine biofouling. Moreover, the intrinsic dynamic surface makes it difficult for biofouling to adhere and ultimately achieves sustainable antifouling property. Notably, the PU50-DMG coating not only presents efficient antibacterial and antialgae properties, but also prevents macroorganisms from settling in the sea for up to 4 months. This provides a pioneer broad-spectrum strategy to explore the marine antifouling coatings.


Assuntos
Antibacterianos , Incrustação Biológica , Macrófagos , Propriedades de Superfície , Incrustação Biológica/prevenção & controle , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Poliuretanos/química , Poliuretanos/farmacologia , Camundongos , Oximas/química , Oximas/farmacologia , Células RAW 264.7 , Tamanho da Partícula , Testes de Sensibilidade Microbiana , Estrutura Molecular
8.
Front Public Health ; 12: 1378979, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756886

RESUMO

Objective: This study aimed to develop and validate a serial multiple mediation model to investigate the association between instrumental activities of daily living (IADL) function and cognitive status among older adults while exploring the underlying mechanisms. Methods: This cross-sectional study involved 3,665 individuals aged 60 years and older who participated in the China Health and Retirement Longitudinal Survey (CHARLS). A serial multiple mediation model was utilized to explore the direct and indirect relationship between IADL function and cognitive status and whether sleep duration, social engagement, and depressive symptoms mediated this relationship. Results: Decreased IADL function was associated with worse cognitive status [effect = -0.620, 95% CI: (-0.692, -0.540)]. Sleep duration, social participation (SP), and depressive symptoms all acted as mediators in the relationship between IADL function and cognitive status. Conclusion: This study found both direct and indirect associations between IADL function and cognitive status, providing new insights into the effective prevention and intervention of cognitive decline among older adults.


Assuntos
Atividades Cotidianas , Cognição , Depressão , Humanos , Masculino , Idoso , Feminino , Estudos Transversais , China , Pessoa de Meia-Idade , Cognição/fisiologia , Estudos Longitudinais , Depressão/epidemiologia , Idoso de 80 Anos ou mais , Disfunção Cognitiva , Participação Social , Análise de Mediação , População do Leste Asiático
9.
Materials (Basel) ; 17(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38793271

RESUMO

Normally, the acidic impurities in hemihydrate phosphogypsum (HPG) must be neutralized when HPG is utilized, and a little amount of calcium hydroxide (CH) is the best choice. In this paper, the effects of excessive CH (5 wt.%, 10 wt.%, 15 wt.% and 20 wt.% of HPG) for carbonation curing on the performance of hardened HPG paste were studied. According to the results of macro tests and microanalyses of XRD, TG, SEM-EDS, MIP and N2 physisorption, it could be verified that CaF2, Ca3(PO4)2 and a large amount of nanoscale CaCO3 crystals were produced as a result of neutralization and carbonation, and the compressive strength and the water resistance of carbonated HPG + CH paste were significantly improved due to the effects of nanoscale CaCO3 crystals on pore refinement and the coverage on the surfaces of gypsum crystals of the hardened paste. Therefore, this study suggests a feasible and green method for recycling HPG/PG, with the collaborative effects of neutralization, performance enhancement and reductions in CO2 emissions.

10.
Front Psychiatry ; 15: 1395198, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690204

RESUMO

Aim: Baseline cognitive functions of patients predicted the efficacy of cognitive remediation therapy (CRT), but results are mixed. Eye movement is a more objective and advanced assessment of cognitive functions than neuropsychological testing. We aimed to investigate the applicability of eye movements in predicting cognitive improvement after patients with schizophrenia were treated with CRT. Methods: We recruited 79 patients with schizophrenia to complete 8 weeks of CRT and assessed their cognitive improvement outcomes. Eye movements were assessed by prosaccades, antisaccades, and free-viewing tasks at baseline, and neuropsychological tests in four cognitive domains were assessed before and after treatment to calculate treatment outcomes. Predictors of demographic information, clinical characteristics, and eye movement measures at baseline on cognitive improvement outcomes were analyzed using logistic regression analysis. We further compared the predictive performance between eye movement measurements and neuropsychological test regarding the effect of CRT on cognitive improvement, and explored factors that could be affect the treatment outcomes in different cognitive domains. Results: As operationally defined, 33 patients showed improved in cognition (improved group) and 46 patients did not (non-improved group) after CRT. Patients with schizophrenia being employed, lower directional error rate in antisaccade task, and lower the gap effect (i.e., the difference in saccadic latency between the gap condition and overlap condition) in prosaccade task at baseline predicted cognitive improvement in CRT. However, performance in the free-viewing task not associated with cognitive improvement in patients in CRT. Our results show that eye-movement prediction model predicted the effect of CRT on cognitive improvement in patients with schizophrenia better than neuropsychological prediction model in CRT. In addition, baseline eye-movements, cognitive reserve, antipsychotic medication dose, anticholinergic cognitive burden change, and number of training sessions were associated with improvements in four cognitive domains. Conclusion: Eye movements as a non-invasiveness, objective, and sensitive method of evaluating cognitive function, and combined saccadic measurements in pro- and anti-saccades tasks could be more beneficial than free-viewing task in predicting the effect of CRT on cognitive improvement in patients with schizophrenia.

11.
Inorg Chem ; 63(21): 9983-9991, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38757519

RESUMO

Electrocatalytic CO2 reduction reaction (CO2RR) to ethanol has been widely researched for potential commercial application. However, it still faces limited selectivity at a large current density. Herein, Mo4+-doped CuS nanosheet-assembled hollow spheres are constructed to address this issue. Mo4+ ion doping modifies the local electronic environments and diversifies the binding sites of CuS, which increases the coverage of linear *COL and produces bridge *COB for subsequent *COL-*COH coupling toward ethanol production. The optimal Mo9.0%-CuS can electrocatalyze CO2 to ethanol with a faradaic efficiency of 67.5% and a partial current density of 186.5 mA cm-2 at -0.6 V in a flow cell. This work clarifies that doping high valence transition metal ions into Cu-based sulfides can regulate the coverage and configuration of related intermediates for ethanol production during the CO2RR in a flow cell.

12.
Res Sq ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38562721

RESUMO

A major challenge in neuroscience is to visualize the structure of the human brain at different scales. Traditional histology reveals micro- and meso-scale brain features, but suffers from staining variability, tissue damage and distortion that impedes accurate 3D reconstructions. Here, we present a new 3D imaging framework that combines serial sectioning optical coherence tomography (S-OCT) with a deep-learning digital staining (DS) model. We develop a novel semi-supervised learning technique to facilitate DS model training on weakly paired images. The DS model performs translation from S-OCT to Gallyas silver staining. We demonstrate DS on various human cerebral cortex samples with consistent staining quality. Additionally, we show that DS enhances contrast across cortical layer boundaries. Furthermore, we showcase geometry-preserving 3D DS on cubic-centimeter tissue blocks and visualization of meso-scale vessel networks in the white matter. We believe that our technique offers the potential for high-throughput, multiscale imaging of brain tissues and may facilitate studies of brain structures.

13.
J Hepatol ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38670321

RESUMO

BACKGROUND & AIMS: The precise pathomechanisms underlying the development of non-alcoholic steatohepatitis (NASH, also known as metabolic dysfunction-associated steatohepatitis [MASH]) remain incompletely understood. In this study, we investigated the potential role of EF-hand domain family member D2 (EFHD2), a novel molecule specific to immune cells, in the pathogenesis of NASH. METHODS: Hepatic EFHD2 expression was characterized in patients with NASH and two diet-induced NASH mouse models. Single-cell RNA sequencing (scRNA-seq) and double-immunohistochemistry were employed to explore EFHD2 expression patterns in NASH livers. The effects of global and myeloid-specific EFHD2 deletion on NASH and NASH-related hepatocellular carcinoma were assessed. Molecular mechanisms underlying EFHD2 function were investigated, while chemical and genetic investigations were performed to assess its potential as a therapeutic target. RESULTS: EFHD2 expression was significantly elevated in hepatic macrophages/monocytes in both patients with NASH and mice. Deletion of EFHD2, either globally or specifically in myeloid cells, improved hepatic steatosis, reduced immune cell infiltration, inhibited lipid peroxidation-induced ferroptosis, and attenuated fibrosis in NASH. Additionally, it hindered the development of NASH-related hepatocellular carcinoma. Specifically, deletion of myeloid EFHD2 prevented the replacement of TIM4+ resident Kupffer cells by infiltrated monocytes and reversed the decreases in patrolling monocytes and CD4+/CD8+ T cell ratio in NASH. Mechanistically, our investigation revealed that EFHD2 in myeloid cells interacts with cytosolic YWHAZ (14-3-3ζ), facilitating the translocation of IFNγR2 (interferon-γ receptor-2) onto the plasma membrane. This interaction mediates interferon-γ signaling, which triggers immune and inflammatory responses in macrophages during NASH. Finally, a novel stapled α-helical peptide targeting EFHD2 was shown to be effective in protecting against NASH pathology in mice. CONCLUSION: Our study reveals a pivotal immunomodulatory and inflammatory role of EFHD2 in NASH, underscoring EFHD2 as a promising druggable target for NASH treatment. IMPACT AND IMPLICATIONS: Non-alcoholic steatohepatitis (NASH) represents an advanced stage of non-alcoholic fatty liver disease (NAFLD); however, not all patients with NAFLD progress to NASH. A key challenge is identifying the factors that trigger inflammation, which propels the transition from simple fatty liver to NASH. Our research pinpointed EFHD2 as a pivotal driver of NASH, orchestrating the over-activation of interferon-γ signaling within the liver during NASH progression. A stapled peptide designed to target EFHD2 exhibited therapeutic promise in NASH mice. These findings support the potential of EFHD2 as a therapeutic target in NASH.

14.
Int J Mol Sci ; 25(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38612848

RESUMO

The rational design of advanced electrocatalysts at the molecular or atomic level is important for improving the performance of hydrogen evolution reactions (HERs) and replacing precious metal catalysts. In this study, we describe the fabrication of electrocatalysts based on Fe, Co, or Ni single atoms supported on titanium carbide (TiC) using the molten salt method, i.e., TiC-FeSA, TiC-CoSA, or TiC-NiSA, to enhance HER performance. The introduction of uniformly distributed transition-metal single atoms successfully reduces the overpotential of HERs. Overpotentials of TiC-FeSA at 10 mA cm-2 are 123.4 mV with 61.1 mV dec-1 Tafel slope under acidic conditions and 184.2 mV with 85.1 mV dec-1 Tafel slope under alkaline conditions, which are superior to TiC-NiSA and TiC-CoSA. TiC samples loaded with transition-metal single atoms exhibit high catalytic activity and long stability under acidic and basic conditions. Density functional theory calculations indicate that the introduction of transition-metal single atoms effectively reduces the HER barrier of TiC-based electrocatalysts.


Assuntos
Ferro , Níquel , Titânio , Cobalto , Hidrogênio
15.
Heliyon ; 10(5): e27413, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38449607

RESUMO

Dipeptidyl-peptidase-like protein 6 (DPPX) antibody-mediated encephalitis is a rare type of autoimmune encephalitis (AE), which mainly manifests as diarrhea accompanied by weight loss, cognitive decline, epileptic seizures, and even psychiatric symptoms. Remarkably, it is also reported to be associated with tumors, predominantly B-cell lymphoma. Overall, the AE remains uncharacterized clinically and its long-term prognosis remains elusive. Herein, we report the first case of DPPX antibody-mediated AE secondary to breast cancer. Importantly, it substantially improves after aggressive immunotherapy. Our case highlights DPPX antibody-mediated AE as a paraneoplastic syndrome and discusses the pearls in its diagnosis and management.

16.
Small ; : e2310340, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456789

RESUMO

Chondrosarcoma(CS), a prevalent primary malignant bone tumor, frequently exhibits chemotherapy resistance attributed to upregulated anti-apoptosis pathways such as the Bcl-2 family. In this manuscript, a new strategy is presented to augment chemosensitivity and mitigate systemic toxicity by harnessing a nano-enabled drug delivery hydrogel platform. The platform utilizes "PLGA-PEG-PLGA", an amphiphilic triblock copolymer combining hydrophilic polyethylene glycol (PEG) and hydrophobic polylactide glycolide (PLGA) blocks, renowned for its properties conducive to crafting a biodegradable, temperature-sensitive hydrogel. This platform is tailored to encapsulate a ratiometrically designed dual-loaded liposomes containing a first-line chemo option for CS, Doxorubicin (Dox), plus a calculated amount of small molecule inhibitor for anti-apoptotic Bcl-2 pathway, ABT-737. In vitro and in vivo evaluations demonstrate successful Bcl-2 suppression, resulting in the restoration of Dox sensitivity, evident through impeded tumor growth and amplified necrosis rates at the tumor site. This delivery system showcases remarkable thermal responsiveness, injectability, and biodegradability, all finely aligned with the clinical demands of CS treatment. Collectively, this study introduces a transformative avenue for tackling drug resistance in CS chemotherapy, offering significant clinical potential.

17.
Nanomaterials (Basel) ; 14(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38334576

RESUMO

New and efficient sensors of nerve agents are urgently demanded to prevent them from causing mass casualties in war or terrorist attacks. So, in this work, a novel hierarchical nanoheterostructure was synthesized via the direct growth of α-Fe2O3 nanorods onto multiwall carbon nanotube (MWCNT) backbones. Then, the composites were functionalized with hexafluoroisopropanol (HFIP) and successfully applied to detect dimethyl methylphosphonate (DMMP)-sarin simulant gas. The observations show that the HFIP-α-Fe2O3@MWCNT hybrids exhibit outstanding DMMP-sensing performance, including low operating temperature (220 °C), high response (6.0 to 0.1 ppm DMMP), short response/recovery time (8.7 s/11.9 s), as well as low detection limit (63.92 ppb). The analysis of the sensing mechanism demonstrates that the perfect sensing performance is mainly due to the synergistic effect of the chemical interaction of DMMP with the heterostructure and the physical adsorption of DMMP by hydrogen bonds with HFIP that are grafted on the α-Fe2O3@MWCNTs composite. The huge specific surface area of HFIP-α-Fe2O3@MWCNTs composite is also one of the reasons for this enhanced performance. This work not only offers a promising and effective method for synthesizing sensitive materials for high-performance gas sensors but also provides insight into the sensing mechanism of DMMP.

18.
Plant Physiol Biochem ; 208: 108439, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38408396

RESUMO

Putrescine, produced via the arginine decarboxylase (ADC)/ornithine decarboxylase (ODC)-mediated pathway, is an initial precursor for polyamines metabolism and the root-specific biosynthesis of medicinal tropane alkaloids (TAs). These alkaloids are widely used as muscarinic acetylcholine antagonists in clinics. Although the functions of ODC in biosynthesis of polyamines and TAs have been well investigated, the role of ADC is still poorly understood. In this study, enzyme inhibitor treatment showed that ADC was involved in the biosynthesis of putrescine-derived metabolites and root growth in Atropa belladonna. Further analysis found that there were six ADC unigenes in the A. belladonna transcriptome, with two of them, AbADC1 and AbADC2, exhibiting high expression in the roots. To investigate their roles in TAs/polyamines metabolism and root growth, RNA interference (RNAi) was used to suppress either AbADC1 or AbADC2 expression in A. belladonna hairy roots. Suppression of the AbADC1 expression resulted in a significant reduction in the putrescine content and hairy root biomass. However, it had no noticeable effect on the levels of N-methylputrescine and the TAs hyoscyamine, anisodamine, and scopolamine. On the other hand, suppression of AbADC2 expression markedly reduced the levels of putrescine, N-methylputrescine, and TAs, but had no significant effect on hairy root biomass. According to ß-glucuronidase (GUS) staining assays, AbADC1 was mainly expressed in the root elongation and division region while AbADC2 was mainly expressed in the cylinder of the root maturation region. These differences in expression led to functional divergence, with AbADC1 primarily regulating root growth and AbADC2 contributing to TA biosynthesis.


Assuntos
Alcaloides , Atropa belladonna , Carboxiliases , Atropa belladonna/genética , Atropa belladonna/metabolismo , Putrescina/metabolismo , Tropanos/metabolismo
19.
Adv Mater ; 36(24): e2313004, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38382460

RESUMO

Moiré effects arising from mutually twisted metasurfaces have showcased remarkable wave manipulation capabilities, unveiling tantalizing emerging phenomena such as acoustic moiré flat bands and topological phase transitions. However, the pursuit of strong near-field coupling in layers has necessitated acoustic moiré metasurfaces to be tightly stacked at narrow distances in the subwavelength range. Here, moiré effects beyond near-field interlayer coupling in acoustics are reported and the concept of coupling-immune moiré metasurfaces is proposed. Remote acoustic moiré effects decoupled from the interlayer distance are theoretically, numerically, and experimentally demonstrated. Tunable out-of-plane acoustic beam scanning is successfully achieved by dynamically controlling twist angles. The engineered coupling-immune properties are further extended to multilayered acoustic moiré metasurfaces and manipulation of acoustic vortices. Good robustness against external disturbances is also observed for the fabricated coupling-immune acoustic moiré metasurfaces. The presented work unlocks the potential of twisted moiré devices for out-of-plane acoustic beam shaping, enabling practical applications in remote dynamic detection, and multiplexed underwater acoustic communication.

20.
BMC Public Health ; 24(1): 483, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38365666

RESUMO

BACKGROUND: Few studies have clarified the mechanisms linking social anxiety and loneliness in older populations. The study aimed to explore how social network mediate the relationship between social anxiety and loneliness in older adults, with perceived social support playing a moderating role. METHODS: A total of 454 older patients completed the Social Avoidance and Distress Scale, Lubben Social Network Scale-6, Chinese version of the Short Loneliness Scale and Perceived Social Support Scale. Bootstrap and simple slope methods were used to test the moderated mediation model. RESULTS: Social anxiety had a significant positive predictive effect on loneliness and social network partially mediated this relationship. The relationship between social anxiety and social network, as well as the relationship between social network and loneliness, was moderated by perceived social support. Specifically, perceived social support buffered the effects of social anxiety on social network, but the buffering effect diminished with increasing levels of social anxiety. On the social network and loneliness pathway, the social network of older persons with higher perceived social support has a stronger prediction of loneliness. CONCLUSIONS: The study found that social anxiety can contribute to loneliness by narrowing older adults' social network. High perceived social support can buffer this process, but do not overstate its protective effects. Thus, interventions to reduce social anxiety and improve social network and social support may help prevent and alleviate loneliness in older adults.


Assuntos
Solidão , Apoio Social , Humanos , Idoso , Idoso de 80 Anos ou mais , Comportamento Social , Povo Asiático , Ansiedade
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