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1.
Small ; : e2207720, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732904

RESUMO

Conjugated coordination polymers (CCPs) have attracted extensive attention for various applications related to energy storage and conversion in the past few years, despite that there are many CCPs with unclear chemical states and structures. Here, linear CCPs (LCCPs), with metal-O4 active sites grown on carbon paper (CP) for oxygen evolution reaction (OER), are presented. The LCCPs with high crystallinity and simple structures exhibit the order of electrocatalytic activity of Co-O4  > Ni-O4  > Fe-O4 in terms of the metal-O4 centers. The Co-based LCCP shows higher OER performance (263 mV at 10 mA cm-2 ) and better durability (90 h at 30 mA cm-2 ) than commercial IrO2 /CP. The structures and chemical states of LCCPs are carefully investigated, and density functional theory is used to reveal the mechanism of OER at the central metal site. This investigation into LCCPs provides new sights for a better understanding of CCPs and expands the applications of LCCPs with metal-O4 sites.

2.
Sci Data ; 10(1): 51, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693875

RESUMO

Recently, increasing studies are indicating a close association between dysregulated enhancers and neurodegenerative diseases, such as Alzheimer's disease (AD). However, their contributions were poorly defined for lacking direct links to disease genes. To bridge this gap, we presented the Hi-C datasets of 4 AD patients, 4 dementia-free aged and 3 young subjects, including 30 billion reads. As applications, we utilized them to link the AD risk SNPs and dysregulated epigenetic marks to the target genes. Combining with epigenetic data, we observed more detailed interactions among regulatory regions and found that many known AD risk genes were under long-distance promoter-enhancer interactions. For future AD and aging studies, our datasets provide a reference landscape to better interpret findings of association and epigenetic studies for AD and aging process.


Assuntos
Envelhecimento , Doença de Alzheimer , Cromatina , Idoso , Humanos , Envelhecimento/genética , Doença de Alzheimer/genética , Epigenômica
3.
Nat Prod Res ; : 1-6, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36622886

RESUMO

Two new benzophenone derivatives (1 and 2), named Pogonatone C and pogonatone D, were isolated from the moss Pogonatum spinulosum. Their structures were elucidated by spectroscopic data analyses. The cytotoxicity of compounds for HepG2, HCT-116, A-549 and PANC-1 cells line was also evaluated by using the MTT method. Pogonatone C (1) displays high cytotoxicity on PANC-1 cell with IC50 value of 9.2 µM.

5.
Adv Sci (Weinh) ; : e2206094, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658692

RESUMO

High-performance multilayer dielectric elastomer actuators (DEAs) are well-positioned to overcome the insufficient output force and energy density as artificial muscles. However, due to the fabrication process, the multilayer DEAs with nonmodifiable structures often suffer from the limitation of short lifespans and scalable preparation. Herein, reusable multilayer DEAs with the detachable and reconfigurable structure are fabricated. This is achieved by realizing scalable compliant electrodes using the continuous spatial confining forced network assembly (CSNA) method and combining the vacuum lamination (VL) approach to have good attachability and detachability with the VHB dielectric elastomer. The flexible roller-based CSNA method is used to prepare the large area compliant electrodes composed of α, ω-dihydroxy polydimethylsiloxane and electrically conductive nanoparticles. The fabricated electrodes can continuously work over 10 000 cycles at 40% strained stretching and maintain smooth surfaces to construct multilayer DEAs. Moreover, owing to the detachable configuration of the DEAs, the electrodes can also be recovered and reused for building new actuators. The lower limb assistive device is demonstrated by detachable multilayer spring roll DEAs, achieving approximately 3.1 degrees of flexion and extension movement of knee models under a voltage of 7 kV. The detachable and reconfigurable multilayer DEAs shed new light on the applications of wearable assistive devices.

6.
Brain Res ; : 148247, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36669713

RESUMO

Traditional Chinese medicine has emerged as promising targets for ischemic stroke (IS) therapy, yet the mechanism remains elusive. The current study was performed with an aim to investigate the action and mechanism of Tongqiao Huoxue decoction (TQHXD) affecting the neurological impairment secondary to IS based on network pharmacology. Based on network pharmacology and bioinformatics analysis, target genes and pathways involved in the treatment of TQHXD against IS were predicted. Serum containing TQHXD was prepared through blood collection from C57BL/6 mice after intragastric administration of TQHXD. The main results exhibited that Prostaglandin-endoperoxide synthase 2 (PTGS2) exhibited an abundance in IS and enrichment in the NF-kappa B signaling pathway, holding the potential as targets related to TQHXD treatment for IS. TQHXD was found to rescue cell viability, inhibit apoptosis, and alleviate inflammation under oxygen and glucose deprivation and reoxygenation (OGD/R) exposure. Furthermore, our in vivo experiment validated the protective function of TQHXD in ischemic brain damage stimulated by middle cerebral artery occlusion (MCAO). This protective action of TQHXD could be attenuated by overexpressing nuclear factor (NF)-kappa B, which was dependent on PTGS2. Collectively, TQHXD was demonstrated to ameliorate IS-induced neurological impairment by blocking the NF-kappa B signaling pathway and down-regulating PTGS2.

7.
World J Clin Cases ; 11(1): 164-171, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36687181

RESUMO

BACKGROUND: Thymic lipofibroadenomas are extremely rare. In this study, we investigated the clinicopathological characteristics of thymic lipofibroadenomas. CASE SUMMARY: This study included three patients with thymic lipofibroadenomas. We retrospectively analyzed the patient data to determine the clinicopathological characteristics of thymic lipofibroadenomas. The study included one man and two women [mean age, 43 (33-59) years]. All patients were non-smokers and presented with well-defined anterior mediastinal tumors. The cut surfaces of the tumors were solid, with a mixture of yellow and white areas. Microscopic evaluation of resected specimens showed scattered cord-like structures of epithelial cells embedded within abundant fibrotic and hyaline stroma admixed with variable quantities of adipose tissue. One patient showed hyperplastic thymic tissue in a part of the tumor. CONCLUSION: Thymic lipofibroadenomas are an extremely rare type of benign thymic tumor. Surgical removal of lipofibroadenomas is usually curative.

8.
Nat Neurosci ; 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36690898

RESUMO

Cell-to-cell transmission and subsequent amplification of pathological proteins promote neurodegenerative disease progression. Most research on this has focused on pathological protein seeds, but how their normal counterparts, which are converted to pathological forms during transmission, regulate transmission is less understood. Here we show in cultured cells that phosphorylation of soluble, nonpathological α-synuclein (α-Syn) at previously identified sites dramatically affects the amplification of pathological α-Syn, which underlies Parkinson's disease and other α-synucleinopathies, in a conformation- and phosphorylation site-specific manner. We performed LC-MS/MS analyses on soluble α-Syn purified from Parkinson's disease and other α-synucleinopathies, identifying many new α-Syn post-translational modifications (PTMs). In addition to phosphorylation, acetylation of soluble α-Syn also modified pathological α-Syn transmission in a site- and conformation-specific manner. Moreover, phosphorylation of soluble α-Syn could modulate the seeding properties of pathological α-Syn. Our study represents the first systematic analysis how of soluble α-Syn PTMs affect the spreading and amplification of pathological α-Syn, which may affect disease progression.

9.
Phys Chem Chem Phys ; 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36692210

RESUMO

We report a joint photoelectron spectroscopic and relativistic quantum chemistry study on gaseous NUO2-. The electron affinity (EA) of the neutral NUO2 molecule is reported for the first time with a value of 2.602(28) eV. The U-O and U-N stretching vibrational modes for the ground state and the first excited state are observed for NUO2. The geometric and electronic structures of both the anions and the corresponding neutrals are investigated by relativistic quantum chemistry calculations to interpret the photoelectron spectra and to provide insights into the nature of the chemical bonding. Both the ground state of the anion and neutral are calculated to be planar structures with C2v symmetry. Unlike the "T"-shape structure of UO3 which has a quasi-linear O-U-O angle, both the ground-state geometries of the anion and neutral have O-U-O bond angles of around 90°. The significant contraction of the O-U-O bond angle indicates the strong interaction between the U and N atoms compared with the "additional" oxygen in UO3. The chemical bonding calculation indicates that multiple bonding of U(VI) can occur in NUO2- and NUO2, and the UVI-N bond is significantly more covalent than the U-O bond. The current experimental and theoretical results reveal the difference between the U-N and U-O bond in the unified molecular system, and expand our understanding of the bonding capacities of actinide elements with the nitrogen atom.

10.
Adv Sci (Weinh) ; : e2206685, 2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36683174

RESUMO

Photoelectrochemical oxidation of methylene blue is investigated, with particular focus on the difference in kinetics and thermodynamics of decoloration and mineralization employing photoinduced absorption spectroscopy. Hematite and titania photoanodes are used for the comparison of both reactions, which is determined to be associated with the depth of the valence band (3.2 vs 2.5 V for titania and hematite, respectively). Methylene blue is mineralized by the titania photoanode, however it is only oxidized to small fragments by hematite. Such difference is related to the valence band potential that provides the thermodynamic driving force for photogenerated holes in both materials. In addition, the kinetic competition of water oxidation is found to occur on titania by controlling the pH of the electrolyte. In the pH 14 electrolyte, mineralization of methylene blue is suppressed due to the faster and dominant kinetics of water oxidation, in contrast to the complete mineralization in the near neutral electrolyte where water oxidation kinetics are modest. These results clearly address the importance considering both thermodynamic and kinetic challenges of methylene blue oxidation, which has been thought to be an easy molecule to oxidize, as the model reaction in the application of photo(electro)catalysis using metal oxides.

11.
Small Methods ; : e2201322, 2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36683186

RESUMO

Establishing simple, rapid, and highly sensitive molecular assays is crucial for timely diagnosis and effective treatment of drug-resistant tuberculosis. However, current genotypic drug susceptibility testing (DST) still encounters enormous challenges including lower sensitivity than phenotypic DST and insufficient accuracy. Herein, a simple, low-cost, multiplex real-time polymerase chain reaction-based assay is established to achieve highly sensitive detection of low-abundant mutants through competitive wild-type blocking (COWTB). Analytical performance of the COWTB assay can achieve 1% or even 0.1% mutants under background of 10 000 wild-type genomes/test. Furthermore, clinical practice feasibility is evaluated to identify resistance to rifampicin (RIF), isoniazid (INH), and streptomycin (SM) on 92 actual clinical samples, its sensitivity is 93.8% for RIF and 100% for INH and SM, and specificity is 100% each for RIF, INH, and SM when using DNA sequencing as the reference standard. In comparison, the sensitivity of reverse dot blotting assay commonly used in clinics is 93.8%, 90.0%, and 84.6%, and the specificity is 96.1%, 98.6%, and 100% for RIF, INH, and SM, respectively. Importantly, the COWTB assay can also be applicable for other drug-resistant mutations and pave a promising detection strategy to fill the gap between phenotypic and genotypic DST for detecting low-abundant drug-resistant M. tuberculosis.

12.
Materials (Basel) ; 16(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36676230

RESUMO

The effects of dipole interactions on magnetic nanoparticle magnetization and relaxation dynamics were investigated using five nanoparticle (NP) systems with different surfactants, carrier liquids, size distributions, inter-particle spacing, and NP confinement. Dipole interactions were found to play a crucial role in modifying the blocking temperature behavior of the superparamagnetic nanoparticles, where stronger interactions were found to increase the blocking temperatures. Consequently, the blocking temperature of a densely packed nanoparticle system with stronger dipolar interactions was found to be substantially higher than those of the discrete nanoparticle systems. The frequencies of the dominant relaxation mechanisms were determined by magnetic susceptibility measurements in the frequency range of 100 Hz-7 GHz. The loss mechanisms were identified in terms of Brownian relaxation (1 kHz-10 kHz) and gyromagnetic resonance of Fe3O4 (~1.12 GHz). It was observed that the microwave absorption of the Fe3O4 nanoparticles depend on the local environment surrounding the NPs, as well as the long-range dipole-dipole interactions. These significant findings will be profoundly important in magnetic hyperthermia medical therapeutics and energy applications.

13.
Heliyon ; 9(1): e12770, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36691539

RESUMO

Introduction: Heart Failure (HF) is a key area of research in human medicine, and traditional Chinese medicine (TCM) is an important branch of this field. This study aimed to use bibliometric methods to sort out the trajectory of TCM research on HF in this century (2000-2022) from a high dimension and to analyze its characteristics, hotspots and frontiers. Methods: In this study, the search formula "TS=(("traditional Chinese medicine") OR ("Chinese medicine")) AND TS=("heart failure")" was used to find relevant studies included in the Web of Science Core Collection from 2000 to 2022. Targeted literature records were analyzed and mapped using CiteSpace and VOSviewer. Results: The authors and collaborators of this study were still in the formation process, but several well-known scholars were included: YONG WANG, WEI WANG, etc. The main research institutions in this research area were Beijing Univ Chinese Med, China Acad Chinese Med Sc, etc. The main country of study was China. Current research hotspots and frontiers were Qili Qiangxin capsules, extracts (Tanshinone ⅡA, Panax ginseng, etc.), cardiac hypertrophy, ventricular remodeling, oxidative stress, signaling pathways, network pharmacology, etc. Influential journals that publish papers in this field were the Journal of Ethnopharmacology, Scientific Reports, Biomedicine & Pharmacotherapy, etc. The top 3 co-cited journals were Circulation, J ethnopharmacol, and J am coll cardiol. Conclusions: We analyzed valuable details in TCM research on HF in the 21st century, which may help researchers identify potential collaborators and partner institutions, hotspots, and frontiers in the field.

14.
Inorg Chem ; 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693231

RESUMO

We present joint anion photoelectron spectroscopy and theoretical studies for Mn2Ge6- and Mn2Ge7-. Experimental results show that Mn2Ge6- and Mn2Ge7- have vertical electron detachment energies of 2.58 ± 0.08 and 2.88 ± 0.08 eV, respectively. Both Mn2Ge6- and Mn2Ge6 have Cs symmetric structures with a Mn atom attached to a pentagonal bipyramid MnGe6. Both Mn2Ge7- and Mn2Ge7 have C2v symmetric structures, which can be considered as two Mn2Ge4 tetragonal bipyramids sharing a MnGeMn face. According to chemical bonding analyses, Mn2Ge6 could be considered as a (MnII)(MnGe62-) complex. Theoretical calculations predict that the extension of Mn2Ge7 to Mn2nGe4n+3 may be able to produce a new type of Mn-doped germanium nanostructure.

15.
Carbohydr Polym ; 304: 120460, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36641186

RESUMO

Fucoidans are valuable marine polysaccharides with various bioactivities and physicochemical properties. However, its digestive properties, mucoadhesive properties, and bioactivity in the gastrointestinal tract are still unclear. In this study, simulated digestion, fecal fermentation in vitro, and rheology models were utilized to investigate the chain conformation, influence on gut microbiota, and mucin adhesive properties of fucoidan from the sea cucumber Thelenota ananas (Ta-FUC). The results showed that Ta-FUC was nondigestible with a temporary decrease in molecular weight in gastric conditions, accompanied by the chain conformation becoming more flexible. Moreover, Ta-FUC exhibited strong mucin adhesive function in the simulated intestinal environment, with supramolecular disulfide, hydrogen, and hydrophobic interactions in order of intensity. During fermentation, Ta-FUC was degraded by the intestinal flora to produce various short-chain fatty acids and promoted the relative abundance of Bacteroidota and Firmicutes, reducing the proportion of Proteobacteria. Therefore, these results indicate that Ta-FUC could be a potential prebiotic and ingredient for developing targeted delivery systems in the functional food and pharmaceutical industries.


Assuntos
Microbioma Gastrointestinal , Pepinos-do-Mar , Animais , Intestinos , Pepinos-do-Mar/química , Polissacarídeos/química , Fermentação
16.
Neurosci Lett ; 798: 137058, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36623760

RESUMO

BACKGROUND AND AIM: Endoplasmic reticulum (ER) stress participates in the occurrence and development of depression, but the underlying mechanism is not fully understood. This study aimed to investigate the behavioral performance and intracerebral molecular changes in an ER stress model of male rats. METHODS: Intrahippocampal injection of tunicamycin (TM) was performed on male rats as a model of ER stress. The body weight was determined, and behavioral tests, including sucrose preference test (SPT), open field test (OFT), and forced swimming test (FST), were performed to evaluate depressive and anxiety-like phenotypes within 8 days after injection. The levels of chaperone-mediated autophagy (CMA), synaptic proteins, and neuroinflammation related factors in this model were measured via real-time quantitative PCR and Western blot analysis. RESULTS: Intrahippocampal injection of TM (2 or 1 µg) induced depression-like behaviors in rats, as indicated by the reduced body weight, sucrose preference in SPT, central time in OFT, and increased immobility time in FST. The mRNA and protein levels of GRP78, ATF4, CHOP, LAMP2A, IL-1ß, IL-6, and TNF-α were significantly increased, while the expressions of MEF2D, PSD95, SYN, p-CREB (Ser133), and BDNF were significantly decreased in the hippocampus in the model group compared with the sham group. CONCLUSIONS: These results confirmed that intrahippocampal injection of TM was a valid method to induce an ER stress rat model with depression-like behaviors accompanied by decreased synaptic protein expression and neuroinflammation. The alteration in CMA-related proteins in this ER stress depression model indicated the involvement of CMA in the development of depression.

17.
Bioorg Chem ; 132: 106381, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36706532

RESUMO

Two enantiomeric pairs of macrocyclic acylphloroglucinols (1a/1b and 2a/2b) with an unprecedented carbon skeleton featuring a bicyclo[12.3.1]octadecane core, together with an undescribed biogenetically related long-chain acylphloroglucinol (3), were isolated from Syzygium szemaoense. Their structures were fully established by spectroscopic method, X-ray crystallographic analysis, and ECD calculation. Compounds 1b and 2a/2b exhibited inhibition against death-associated protein kinase-related apoptosis inducing protein kinase 2 (DRAK2) and ATP citrate lyase (ACLY), respectively.

18.
Int J Biol Macromol ; 229: 1036-1043, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36603727

RESUMO

Ammonia and nitrite are nitrogenous pollutants in aquaculture effluents, which pose a major threat to the health of aquatic animals. In this study, we developed a nitrogen conversion strategy based on synthesis of poly-γ-glutamic acid (γ-PGA) by Bacillus subtilis NX-2. The nitrogen removal efficiency of NX-2 was closely related to synthesizing γ-PGA, and was positively correlated with the inoculum level. The degradation rates of ammonia nitrogen and nitrite at 104 CFU/mL were 84.42 % and 62.56 %, respectively. Through adaptive laboratory evolution (ALE) experiment, we obtained a strain named ALE 5 M with ammonia degradation rate of 98.03 % and nitrite of 93.62 % at the inoculum level of 104 CFU/mL. Transcriptome analysis showed that the strain was more likely to produce γ-PGA after ALE. By enzyme activity and qPCR analysis, we confirmed that ALE 5 M degraded ammonia nitrogen through γ-PGA synthesis, which provided a new way for nitrogen removal in aquaculture water.


Assuntos
Amônia , Ácido Glutâmico , Ácido Glutâmico/metabolismo , Amônia/metabolismo , Nitrogênio/metabolismo , Nitritos/metabolismo , Bacillus subtilis/metabolismo , Ácido Poliglutâmico/metabolismo , Aquicultura
19.
Alzheimers Res Ther ; 15(1): 5, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609457

RESUMO

BACKGROUND: Dementia and psychotropic medications are discussed as risk factors for severe/lethal outcome of the coronavirus disease 2019 (COVID-19). We aimed to explore the associations between the presence of dementia and medication use with mortality in the hospitalized and discharged patients who suffered from COVID-19. METHODS: We conducted an open-cohort observational study based on electronic patient records from nine geriatric care clinics in the larger Stockholm area, Sweden, between February 28, 2020, and November 22, 2021. In total, we identified 5122 hospitalized patients diagnosed with COVID-19, out of which 762 (14.9%) patients had concurrent dementia and 4360 (85.1%) were dementia-free. Patients' age, sex, baseline oxygen saturation, comorbidities, and medication prescription (cardiovascular and psychotropic medication) were registered at admission. The hazard ratios (HRs) with 95% confidence intervals (CIs) of in-hospital, 30-day, 90-day, 365-day post-discharge, and overall mortality during the follow-up were obtained. Then, the associations of dementia and medication use with mortality were determined using proportional hazards regression with time since entry as a time scale. RESULTS: After adjustment, dementia was independently associated with 68% higher in-hospital mortality among COVID-19 patients compared to patients who were dementia-free at admission [HRs (95% CI) 1.68 (1.37-2.06)]. The increase was consistent post-discharge, and the overall mortality of dementia patients was increased by 59% [1.59 (1.40-1.81)]. In addition, the prescription of antipsychotic medication at hospital admission was associated with a 70% higher total mortality risk [1.70 (1.47-1.97)]. CONCLUSIONS: The clinical co-occurence of dementia and COVID-19 increases the short- and long-term risk of death, and the antipsychotics seem to further the risk increase. Our results may help identify high-risk patients in need of more specialized care when infected with COVID-19.


Assuntos
Antipsicóticos , COVID-19 , Humanos , Idoso , Assistência ao Convalescente , Alta do Paciente , Psicotrópicos/uso terapêutico , Antipsicóticos/uso terapêutico
20.
J Ethnopharmacol ; 306: 116130, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36621661

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Garcinia oligantha Merr. is an ethnomedicine plant mainly distributed in Guangdong and Hainan, China. It has the effects of heat-clearing and detoxicating, which has been used by local ethnic minorities to treat a variety of diseases, including inflammation, internal heat, toothache and scald. THE AIM OF THE REVIEW: This review summarizes and discusses the progress of the chemical compounds and biological activities of G. oligantha that have been studied in recent years to provide the direction for the prospective research and applications of G. oligantha. MATERIALS AND METHODS: The relevant literature about G. oligantha was accessible from ancient Chinese medical books and records, theses, as well as major scientific databases such as Google Scholar, PubMed, Web of Science, ScienceDirect, SciFinder, Baidu Scholar and China National Knowledge Infrastructure (CNKI). RESULTS: To date, more than 150 chemical compounds were isolated from this plant, including xanthones, volatile oil, fatty acid, benzofurane derivative and biphenyl compounds. Xanthones are the main bioactive compounds that exhibit diverse biological effects, such as antitumor, analgesic, anti-inflammatory, antioxidative, neuroprotective, antimalarial and antibacterial effects, which are consistent with its traditional uses as a folk medicine. Modern pharmacological studies show that these compounds participate in a variety of signaling pathways underlying different pathophysiologies, making them a valuable medicinal resource. CONCLUSION: G. oligantha is an ethnomedicine with a long history. However, due to regional and cultural constraints, the popularisation and use of ethnomedicine are still limited. Modern pharmacological and chemical research suggest that G. oligantha contains a variety of bioactive compounds and showed diverse biological functions, which is worthy of comprehensive and in-depth research. This review summarizes and discusses the recent progress in studies on G. oligantha, looking forward to promote further research and sustainable development of folk medicinal plants.

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