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1.
Phys Chem Chem Phys ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860760

RESUMO

The concept of aromaticity is primarily invented to account for the high stability of conjugated organic compounds that possess a specific structural and chemical stability with (4n + 2) π electrons. In 1988, quasi-aromaticity was theoretically proposed for the Mo3S44+ core in the Mo3(µ3-S)(µ-S)3(χ-dtp)3(µ-dtp) L compound (χ: chelating ligand; dtp: (EtO)2PS2-) illustrated by canonical molecular orbitals. However, the origin of the quasi-aromaticity and chemical bonding remains ambiguous, lacking a thorough analysis in terms of stability and quantitative measurement of the aromatic character. Thus, in this work, we systematically reported the electronic structure and aromaticity of a series of polynuclear metal chalcogenide clusters [M3X4(H2O)9]4+ (M = Cr, Mo, W, and Sg; X = O, S, Se, and Te) to explore an efficient tool of NICS index values at specific points to measure the quasi-aromaticity and to figure out the (d-p-d) π three-center bonding as the predominant origin from the arrangement of three Mo atoms and three bridged X atoms. Interestingly, derived from the Mo3⋯S3 quasi-plane, the extended sandwich cluster model of a S3⋯Mo3⋯S3 (Mo3S6) structure can be seen as the seed unit of the popular MoS2 nanomaterials, with the resemblance between both molecular and periodic systems regarding geometries, electronic structures, and chemical bonding. Additionally, the highly symmetric Mo3S4 core in [Mo3X4(H2O)9]4+ can be arranged in a staggered and stacked manner to create the Mo6S82- building block, corresponding to the crystalline structures in BaMo6S8 Chevrel phases, albeit with slight deformations. But the neutral Mo6S8 cluster can be seen as the seed structure for the Mo3S4 periodic materials for the high resemblance in terms of geometry, electronic structures and chemical bonding. Drawing upon the observed similarities between cluster models and materials, we propose a new concept termed "cluster-assembly" materials. This concept involves the expansion from a high-symmetry and/or aromatic stable cluster seed unit to form the corresponding derivative materials, presenting an alternative paradigm for investigating crystals and enriching our comprehension of the stabilities exhibited by both gas-phase clusters and solid-state materials. The concept of "cluster-assembly" materials not only contributes to the formulation of design strategies for novel materials or stable clusters but also provides valuable insights into the extension of periodic aromaticity.

2.
Transl Stroke Res ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748378

RESUMO

Intracerebral hemorrhage (ICH) imposes a significant burden on patients, and the volume of hematoma plays a crucial role in determining the severity and prognosis of ICH. Although significant recent progress has been made in understanding the cellular and molecular mechanisms of surrounding brain tissue in ICH, our current knowledge regarding the precise impact of hematoma volumes on neural circuit damage remains limited. Here, using a viral tracing technique in a mouse model of striatum ICH, two distinct patterns of injury response were observed in upstream connectivity, characterized by both linear and nonlinear trends in specific brain areas. Notably, even low-volume hematomas had a substantial impact on downstream connectivity. Neurons in the striatum-ICH region exhibited heightened excitability, evidenced by electrophysiological measurements and changes in metabolic markers. Furthermore, a strong linear relationship (R2 = 0.91) was observed between hematoma volumes and NFL damage, suggesting a novel biochemical index for evaluating changes in neural injury. RNA sequencing analysis revealed the activation of the MAPK signaling pathway following hematoma, and the addition of MAPK inhibitor revealed a decrease in neuronal circuit damage, leading to alleviation of motor dysfunction in mice. Taken together, our study highlights the crucial role of hematoma size as a determinant of circuit injury in ICH. These findings have important implications for clinical evaluations and treatment strategies, offering opportunities for precise therapeutic approaches to mitigate the detrimental effects of ICH and improve patient outcomes.

3.
J Asian Nat Prod Res ; : 1-8, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758009

RESUMO

Macrophorins H (4) and L (5), two rare HMG-conjugate macrophorins along with three known macrophorins (1-3), three DMOA-derived meroterpenoids (6-8) and two ergosterol derivates (9-10) were isolated from sterilized rice medium cultured Penicillium sp. NX-05-G-3. Their structures were elucidated by 1D and 2D NMR. The cytotoxicities of all compounds were evaluated, and compounds 1 and 2 showed extensive cytotoxicity against human cancer cell lines Hela, SCC15, MDA-MB-453 and A549, with IC50 values ranging from 17.6 to 32.8 µM.

4.
Gut Microbes ; 16(1): 2356284, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38769683

RESUMO

Inflammatory bowel disease (IBD) is a chronic and recurrent condition affecting the gastrointestinal tract. Disturbed gut microbiota and abnormal bile acid (BA) metabolism are notable in IBD, suggesting a bidirectional relationship. Specifically, the diversity of the gut microbiota influences BA composition, whereas altered BA profiles can disrupt the microbiota. IBD patients often exhibit increased primary bile acid and reduced secondary bile acid concentrations due to a diminished bacteria population essential for BA metabolism. This imbalance activates BA receptors, undermining intestinal integrity and immune function. Consequently, targeting the microbiota-BA axis may rectify these disturbances, offering symptomatic relief in IBD. Here, the interplay between gut microbiota and bile acids (BAs) is reviewed, with a particular focus on the role of gut microbiota in mediating bile acid biotransformation, and contributions of the gut microbiota-BA axis to IBD pathology to unveil potential novel therapeutic avenues for IBD.


Assuntos
Bactérias , Ácidos e Sais Biliares , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Humanos , Ácidos e Sais Biliares/metabolismo , Animais , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética , Disbiose/microbiologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/metabolismo
5.
Neural Regen Res ; 19(11): 2387-2399, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38526275

RESUMO

Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases. Although various studies and reviews have described developments and advancements in brain organoids, few studies have comprehensively summarized and analyzed the global trends in this area of neuroscience. To identify and further facilitate the development of cerebral organoids, we utilized bibliometrics and visualization methods to analyze the global trends and evolution of brain organoids in the last 10 years. First, annual publications, countries/regions, organizations, journals, authors, co-citations, and keywords relating to brain organoids were identified. The hotspots in this field were also systematically identified. Subsequently, current applications for brain organoids in neuroscience, including human neural development, neural disorders, infectious diseases, regenerative medicine, drug discovery, and toxicity assessment studies, are comprehensively discussed. Towards that end, several considerations regarding the current challenges in brain organoid research and future strategies to advance neuroscience will be presented to further promote their application in neurological research.

6.
Int J Biol Macromol ; 261(Pt 1): 129725, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272410

RESUMO

Keratin materials are promising in wound healing acceleration, however, it is a challenge for the keratin to efficiently therapy the impaired wound healing, such as diabetic foot ulcers. Here, we report a keratin/bFGF hydrogel for skin repair of chronic wounds in diabetic rats based on their characteristics of extracellular matrix and growth factor degradation in diabetic ulcer. Recombinant keratin 31 (K31), the most abundant keratin in human hair, exhibited the highly efficient performances in cell adhesion, proliferation and migration. More importantly, the introduction of bFGF into K31 hydrogel significantly enhances the properties of cell proliferation, wound closure acceleration, angiogenesis and skin appendages regeneration. Furthermore, the combination of K31 and bFGF can promote epithelial-mesenchymal transition by inhibiting the expression of E-cadherin and promoting the expression of vimentin and fibronectin. These findings demonstrate the engineered K31/bFGF hydrogel as a promising therapeutic agent for diabetic wound healing.


Assuntos
Diabetes Mellitus Experimental , Pé Diabético , Ratos , Humanos , Animais , Hidrogéis/farmacologia , Hidrogéis/uso terapêutico , Queratinas/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Cicatrização , Pé Diabético/tratamento farmacológico
7.
Small ; 20(9): e2306944, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37852939

RESUMO

Transdermal drug delivery systems based on physical principles have provided a stable, efficient, and safe strategy for disease therapy. However, the intelligent device with real-time control and precise drug release is required to enhance treatment efficacy and improve patient compliance. This review summarizes the recent developments, application scenarios, and drug release characteristics of smart transdermal drug delivery systems fabricated with physical principle. Special attention is paid to the progress of intelligent design and concepts in of physical-based transdermal drug delivery technologies for real-time monitoring and precise drug release. In addition, facing with the needs of clinical treatment and personalized medicine, the recent progress and trend of physical enhancement are further highlighted for transdermal drug delivery systems in combination with pharmaceutical dosage forms to achieve better transdermal effects and facilitate the development of smart medical devices. Finally, the next generation and future application scenarios of smart physical-based transdermal drug delivery systems are discussed, a particular focus in vaccine delivery and tumor treatment.


Assuntos
Inteligência , Medicina de Precisão , Humanos , Preparações de Ação Retardada , Liberação Controlada de Fármacos
8.
Small ; 20(6): e2306451, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37771182

RESUMO

Understanding the signals from the physical microenvironment is critical for deciphering the processes of neurogenesis and neurodevelopment. The discovery of how surrounding physical signals shape human developing neurons is hindered by the bottleneck of conventional cell culture and animal models. Notwithstanding neural organoids provide a promising platform for recapitulating human neurogenesis and neurodevelopment, building neuronal physical microenvironment that accurately mimics the native neurophysical features is largely ignored in current organoid technologies. Here, it is discussed how the physical microenvironment modulates critical events during the periods of neurogenesis and neurodevelopment, such as neural stem cell fates, neural tube closure, neuronal migration, axonal guidance, optic cup formation, and cortical folding. Although animal models are widely used to investigate the impacts of physical factors on neurodevelopment and neuropathy, the important roles of human stem cell-derived neural organoids in this field are particularly highlighted. Considering the great promise of human organoids, building neural organoid microenvironments with mechanical forces, electrophysiological microsystems, and light manipulation will help to fully understand the physical cues in neurodevelopmental processes. Neural organoids combined with cutting-edge techniques, such as advanced atomic force microscopes, microrobots, and structural color biomaterials might promote the development of neural organoid-based research and neuroscience.


Assuntos
Células-Tronco Neurais , Neurogênese , Animais , Humanos , Organoides , Neurônios , Técnicas de Cultura de Células , Encéfalo/fisiologia
9.
Int J Biol Macromol ; 258(Pt 1): 128847, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38123031

RESUMO

Hydroxysteroid dehydrogenases (HSDHs) are crucial for bile acid metabolism and influence the size of the bile acid pool and gut microbiota composition. HSDHs with high activity, thermostability, and substrate selectivity are the basis for constructing engineered bacteria for disease treatment. In this study, we designed mutations at the cofactor binding site involving Thr15 and Arg16 residues of HSDH St-2-2. The T15A, R16A, and R16Q mutants exhibited 7.85-, 2.50-, and 4.35-fold higher catalytic activity than the wild type, respectively, while also displaying an altered substrate preference (from taurocholic acid (TCA) to taurochenodeoxycholic acid (TCDCA)). These mutants showed lower Km and higher kcat values, indicating stronger binding to the substrate and resulting in 3190-, 3123-, and 3093-fold higher kcat/Km values for TCDCA oxidation. Furthermore, the Tm values of the T15A, R16A, and R16Q mutants were found to increase by 4.3 °C, 6.0 °C, and 7.0 °C, respectively. Molecular structure analysis indicated that reshaped internal hydrogens and surface mutations could improve catalytic activity and thermostability, and altered interactions among the catalytic triad, cofactor binding sites, and substrates could change substrate preference. This work provides valuable insights into modifying substrate preference as well as enhancing the catalytic activity and thermostability of HSDHs by targeting the cofactor binding site.


Assuntos
Bactérias , Hidroxiesteroide Desidrogenases , Bactérias/metabolismo , Hidroxiesteroide Desidrogenases/metabolismo , Ácidos e Sais Biliares , Sítios de Ligação , Cinética
10.
Molecules ; 28(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38067620

RESUMO

Dendrobium nobile Lindl., as an endangered medicinal plant within the genus Dendrobium, is widely distributed in southwestern China and has important ecological and economic value. There are a variety of metabolites with pharmacological activity in D. nobile. The alkaloids and polysaccharides contained within D. nobile are very important active components, which mainly have antiviral, anti-tumor, and immunity improvement effects. However, the changes in the compounds and functional genes of D. nobile induced by methyl jasmonate (MeJA) are not clearly understood. In this study, the metabolome and transcriptome of D. nobile were analyzed after exposure to MeJA. A total of 377 differential metabolites were obtained through data analysis, of which 15 were related to polysaccharide pathways and 35 were related to terpenoids and alkaloids pathways. Additionally, the transcriptome sequencing results identified 3256 differentially expressed genes that were discovered in 11 groups. Compared with the control group, 1346 unigenes were differentially expressed in the samples treated with MeJA for 14 days (TF14). Moreover, the expression levels of differentially expressed genes were also significant at different growth and development stages. According to GO and KEGG annotations, 189 and 99 candidate genes were identified as being involved in terpenoid biosynthesis and polysaccharide biosynthesis, respectively. In addition, the co-expression analysis indicated that 238 and 313 transcription factors (TFs) may contribute to the regulation of terpenoid and polysaccharide biosynthesis, respectively. Through a heat map analysis, fourteen terpenoid synthetase genes, twenty-three cytochrome P450 oxidase genes, eight methyltransferase genes, and six aminotransferase genes were identified that may be related to dendrobine biosynthesis. Among them, one sesquiterpene synthase gene was found to be highly expressed after the treatment with MeJA and was positively correlated with the content of dendrobine. This study provides important and valuable metabolomics and transcriptomic information for the further understanding of D. nobile at the metabolic and molecular levels and provides candidate genes and possible intermediate compounds for the dendrobine biosynthesis pathway, which lays a certain foundation for further research on and application of Dendrobium.


Assuntos
Alcaloides , Dendrobium , Transcriptoma , Dendrobium/genética , Dendrobium/metabolismo , Extratos Vegetais/metabolismo , Alcaloides/metabolismo , Terpenos/metabolismo , Metaboloma , Polissacarídeos/metabolismo
13.
Molecules ; 28(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38005375

RESUMO

A facile and efficient visible-light-mediated method for directly converting 1,4-naphthoquinones into dihydrocyclo-buta[b]naphthalene-3,8-diones (DHCBNDOs) under mild and clean conditions without using any photocatalysts is reported. This approach exhibited favorable compatibility with functional groups and afforded a series of DHCBNDOs with excellent regioselectivity and high yields. Moreover, detailed mechanism studies were carried out both experimentally and theoretically. The readily accessible, low-cost and ecofriendly nature of the developed strategy will endow it with attractive applications in organic and medicinal chemistry.

14.
Nat Commun ; 14(1): 6384, 2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37821436

RESUMO

Currently potential preclinical drugs for the treatment of nonalcoholic steatohepatitis (NASH) and NASH-related pathopoiesis have failed to achieve expected therapeutic efficacy due to the complexity of the pathogenic mechanisms. Here we show Tripartite motif containing 26 (TRIM26) as a critical endogenous suppressor of CCAAT/enhancer binding protein delta (C/EBPδ), and we also confirm that TRIM26 is an C/EBPδ-interacting partner protein that catalyses the ubiquitination degradation of C/EBPδ in hepatocytes. Hepatocyte-specific loss of Trim26 disrupts liver metabolic homeostasis, followed by glucose metabolic disorder, lipid accumulation, increased hepatic inflammation, and fibrosis, and dramatically facilitates NASH-related phenotype progression. Inversely, transgenic Trim26 overexpression attenuates the NASH-associated phenotype in a rodent or rabbit model. We provide mechanistic evidence that, in response to metabolic insults, TRIM26 directly interacts with C/EBPδ and promotes its ubiquitin proteasome degradation. Taken together, our present findings identify TRIM26 as a key suppressor over the course of NASH development.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Coelhos , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Transdução de Sinais , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
15.
Molecules ; 28(19)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37836815

RESUMO

Photodynamic therapy (PDT) is an effective noninvasive therapeutic strategy that has been widely used for anti-tumor therapy by the generation of excessive highly cytotoxic ROS. However, the poor water solubility of the photosensitizer, reactive oxygen species (ROS) depleting by high concentrations of glutathione (GSH) in the tumor microenvironment and the activation of DNA repair pathways to combat the oxidative damage, will significantly limit the therapeutic effect of PDT. Herein, we developed a photosensitizer prodrug (CSP) by conjugating the photosensitizer pyropheophorbide a (PPa) and the DNA-damaging agent Chlorambucil (Cb) with a GSH-responsive disulfide linkage and demonstrated a multifunctional co-delivery nanoplatform (CSP/Ola nanoparticles (NPs)) together with DSPE-PEG2000 and PARP inhibitor Olaparib (Ola). The CSP/Ola NPs features excellent physiological stability, efficient loading capacity, much better cellular uptake behavior and photodynamic performance. Specifically, the nanoplatform could induce elevated intracellular ROS levels upon the in situ generation of ROS during PDT, and decrease ROS consumption by reducing intracellular GSH level. Moreover, the CSP/Ola NPs could amplify DNA damage by released Cb and inhibit the activation of Poly(ADP-ribose) polymerase (PARP), promote the upregulation of γ-H2AX, thereby blocking the DNA repair pathway to sensitize tumor cells for PDT. In vitro investigations revealed that CSP/Ola NPs showed excellent phototoxicity and the IC50 values of CSP/Ola NPs against MDA-MB-231 breast cancer cells were as low as 0.05-01 µM after PDT. As a consequence, the co-delivery nanoplatform greatly promotes the tumor cell apoptosis and shows a high antitumor performance with combinational chemotherapy and PDT. Overall, this work provides a potential alternative to improve the therapeutic efficiency of triple negative breast cancer cell (TNBC) treatment by synergistically enhancing DNA damage and disrupting DNA damage repair.


Assuntos
Antineoplásicos , Nanopartículas , Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Dano ao DNA , Linhagem Celular Tumoral , Microambiente Tumoral
16.
Mater Today Bio ; 23: 100807, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37810750

RESUMO

Infectious wounds have become serious challenges for both treatment and management in clinical practice, so development of new antibiotics has been considered an increasingly difficult task. Here, we report the design and synthesis of keratin 31 (K31)-peptide glycine-leucine-amide (PGLa) photopolymerized hydrogels to rescue the antibiotic activity of antibiotics for infectious wound healing promotion. K31-PGLa displayed an outstanding synergistic effect with commercial antibiotics against drug-resistant bacteria by down-regulating the synthesis genes of efflux pump. Furthermore, the photopolymerized K31-PGLa/PEGDA hydrogels effectively suppressed drug-resistant bacteria growth and enhanced skin wound closure in murine. This study provided a promising alternative strategy for infectious wound treatment.

17.
Adv Sci (Weinh) ; 10(28): e2302130, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37544908

RESUMO

Underestimation of the complexity of pathogenesis in nonalcoholic steatohepatitis (NASH) significantly encumbers development of new drugs and targeted therapy strategies. Inactive rhomboid protein 2 (IRHOM2) has a multifunctional role in regulating inflammation, cell survival, and immunoreaction. Although cytokines and chemokines promote IRHOM2 trafficking or cooperate with partner factors by phosphorylation or ubiquitin ligases-mediated ubiquitination to perform physiological process, it remains unknown whether other regulators induce IRHOM2 activation via different mechanisms in NASH progression. Here the authors find that IRHOM2 is post-translationally S-palmitoylated at C476 in iRhom homology domain (IRHD), which facilitates its cytomembrane translocation and stabilization. Fatty-acids challenge can directly promote IRHOM2 trafficking by increasing its palmitoylation. Additionally, the authors identify Zinc finger DHHC-type palmitoyltransferase 3 (ZDHHC3) as a key acetyltransferase required for the IRHOM2 palmitoylation. Fatty-acids administration enhances IRHOM2 palmitoylation by increasing the direct association between ZDHHC3 and IRHOM2, which is catalyzed by the DHHC (C157) domain of ZDHHC3. Meanwhile, a metabolic stresses-triggered increase of ZDHHC3 maintains palmitoylated IRHOM2 accumulation by blocking its ubiquitination, consequently suppressing its ubiquitin-proteasome-related degradation mediated by tripartite motif containing 31 (TRIM31). High-levels of ZDHHC3 protein abundance positively correlate with the severity of NASH phenotype in patient samples. Hepatocyte-specific dysfunction of ZDHHC3 significantly inhibits palmitoylated IRHOM2 deposition, therefore suppressing the fatty-acids-mediated hepatosteatosis and inflammation in vitro, as well as NASH pathological phenotype induced by two different high-energy diets (HFHC & WTDF) in the in vivo rodent and rabbit model. Inversely, specific restoration of ZDHHC3 in hepatocytes markedly provides acceleration over the course of NASH development via increasing palmitoylation of IRHOM2 along with suppression of ubiquitin degradation. The current work uncovers that ZDHHC3-induced palmitoylation is a novel regulatory mechanism and signal that regulates IRHOM2 trafficking, which confers evidence associating the regulation of palmitoylation with NASH progression.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Coelhos , Lipoilação , Inflamação/metabolismo , Fosforilação , Ácidos Graxos , Ubiquitinas/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
18.
Exp Neurol ; 368: 114475, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37451583

RESUMO

Mass effect after intracerebral hemorrhage (ICH) not only mechanically induces the brain damage, but also influences the progress of secondary brain damage. However, the influence of mass effect on the iron overload after ICH is still unclear. Here, a fixed volume of ferrous chloride solution and different volumes of poly(N-isopropylacrylamide) (PNIPAM) hydrogel were co-injected into the right basal ganglia of rats to establish the ICH model with certain degree of iron deposition but different degrees of mass effect. We found that mass effect significantly increased the iron deposition on neuronal cells at 6 h after ICH in a volume-dependent manner. Furthermore, the upregulation of Piezo-2, divalent metal transporter 1 (DMT1), transferrin receptor (TfR), and ferroptosis expressions were noted as the increase of mass effect. In addition, the pERK1/2 inhibitor PD98059 treated ICH rats reversed the upregulation of iron uptake protein and ferroptosis. Our findings revealed the relationship between mass effect and the iron uptake and ferroptosis, which are benefit to understand the brain damage process after ICH.


Assuntos
Lesões Encefálicas , Sobrecarga de Ferro , Ratos , Animais , Encéfalo/metabolismo , Ratos Sprague-Dawley , Hemorragia Cerebral/complicações , Hemorragia Cerebral/metabolismo , Ferro/metabolismo , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/metabolismo , Lesões Encefálicas/metabolismo
19.
Small Methods ; 7(10): e2300390, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37452173

RESUMO

A multi-engine highly integrated microrobot, which is a Janus hemispherical shell structure composed of Pt and α-Fe2 O3 , is successfully developed. The microrobot can be efficiently driven and flexibly regulated by five stimuli, including an optical field, an acoustic field, magnetic field, an electric field, and chemical fuel. In addition, no matter which way it is driven by, the direction can be effectively controlled through the magnetic field regulation. Furthermore, this microrobot can also utilize magnetic or acoustic fields to achieve excellent aggregation control and swarm movement. Finally, this study demonstrates that the microrobots' propulsion can be effectively synergistically enhanced through the simultaneous action of two driving mechanisms, which can greatly improve the performance of the motor in applications, such as pollutant degradation. This multi-engine, highly integrated microrobot not only can adapt to more complex environments and has a wider application range, better application prospects, but also provides important ideas for designing future advanced micro/nanorobots.

20.
Molecules ; 28(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37375306

RESUMO

Naphtho[2,3-b]furan-4,9-dione is an important privileged structural motif which is present in natural products, drugs, and drug candidates. Herein, visible-light-mediated [3+2] cycloaddition reaction for the synthesis of naphtho[2,3-b]furan-4,9-diones and dihydronaphtho[2,3-b]furan-4,9-diones has been developed. Under environmentally friendly conditions, a variety of title compounds were delivered in good yields. This new protocol shows excellent regioselectivity and remarkable functional group tolerance. This approach provides a powerful, green, efficient, and facile means to expand the structural diversity of naphtho[2,3-b]furan-4,9-diones and dihydronaph-tho[2,3-b]furan-4,9-diones as promising scaffolds for novel drug discovery.

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