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1.
J Pharm Anal ; 14(4): 100905, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38665224

RESUMO

Epigenomic imbalance drives abnormal transcriptional processes, promoting the onset and progression of cancer. Although defective gene regulation generally affects carcinogenesis and tumor suppression networks, tumor immunogenicity and immune cells involved in antitumor responses may also be affected by epigenomic changes, which may have significant implications for the development and application of epigenetic therapy, cancer immunotherapy, and their combinations. Herein, we focus on the impact of epigenetic regulation on tumor immune cell function and the role of key abnormal epigenetic processes, DNA methylation, histone post-translational modification, and chromatin structure in tumor immunogenicity, and introduce these epigenetic research methods. We emphasize the value of small-molecule inhibitors of epigenetic modulators in enhancing antitumor immune responses and discuss the challenges of developing treatment plans that combine epigenetic therapy and immunotherapy through the complex interaction between cancer epigenetics and cancer immunology.

2.
Ying Yong Sheng Tai Xue Bao ; 35(3): 817-826, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646770

RESUMO

To explore the causes of red tides in Qinhuangdao coastal water, we conducted surveys on both water quality and red tides during April to September of 2022 and analyzed the relationships between main environmental factors and red tide organisms through the factor analysis and canonical correspondence analysis. The results showed that there were eight red tides along the coast of Qinhuangdao in 2022, with a cumulative blooming area of 716.1 km2. The red tides could be divided into three kinds based on the major blooming organisms and occurrence time, Noctiluca scintillans bloom, diatom-euglena (Skeletonema costatum, Eutreptiella gymnastica, Pseudo-nitzschia spp.) bloom, and dinoflagellate (Scrippsiella trochoidea and Ceratium furca) bloom. Seasonal factor played roles mainly during July to September, while inorganic nutrients including nitrogen and phosphorus influenced the blooms mainly in April and July. The canonical correspondence analysis suggested that N. scintillans preferred low temperature, and often bloomed with high concentrations of ammonium nitrogen and dissolved inorganic phosphorus. S. costatum, E. gymnastica, and Pseudo-nitzschia spp. could tolerate broad ranges of various environmental factors, but favored high temperature and nitrogen-rich seawater. C. furca and S. trochoidea had higher survival rate and competitiveness in phosphate-poor waters. Combined the results from both analyses, we concluded that the causes for the three kinds of red tide processes in Qinhuangdao coastal areas in 2022 were different. Adequate diet algae and appropriate water temperature were important factors triggering and maintaining the N. scintillans bloom. Suitable temperature, salinity and eutrophication were the main reasons for the diatom-euglena bloom. The abundant nutrients and seawater disturbance promoted the germination of S. trochoidea cysts, while phosphorus limitation caused the blooming organism switched to C. furca and maintained the bloom hereafter.


Assuntos
Diatomáceas , Dinoflagellida , Monitoramento Ambiental , Proliferação Nociva de Algas , Água do Mar , China , Dinoflagellida/crescimento & desenvolvimento , Água do Mar/análise , Água do Mar/química , Diatomáceas/crescimento & desenvolvimento , Oceanos e Mares , Fósforo/análise , Nitrogênio/análise , Estações do Ano
3.
Natl Sci Rev ; 11(5): nwae081, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38577675

RESUMO

Hierarchical self-assembly with long-range order above centimeters widely exists in nature. Mimicking similar structures to promote reaction kinetics of electrochemical energy devices is of immense interest, yet remains challenging. Here, we report a bottom-up self-assembly approach to constructing ordered mesoporous nanofibers with a structure resembling vascular bundles via electrospinning. The synthesis involves self-assembling polystyrene (PS) homopolymer, amphiphilic diblock copolymer, and precursors into supramolecular micelles. Elongational dynamics of viscoelastic micelle solution together with fast solvent evaporation during electrospinning cause simultaneous close packing and uniaxial stretching of micelles, consequently producing polymer nanofibers consisting of oriented micelles. The method is versatile for the fabrication of large-scale ordered mesoporous nanofibers with adjustable pore diameter and various compositions such as carbon, SiO2, TiO2 and WO3. The aligned longitudinal mesopores connected side-by-side by tiny pores offer highly exposed active sites and expedite electron/ion transport. The assembled electrodes deliver outstanding performance for lithium metal batteries.

4.
Pest Manag Sci ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629775

RESUMO

BACKGROUND: Saliva has a crucial role in determining the compatibility between piercing-sucking insects and their hosts. The brown planthopper (BPH) Nilaparvata lugens, a notorious pest of rice in East and Southeast Asia, secretes gelling and watery saliva when feeding on rice sap. Nlsalivap-5 (NlSP5) and Nlsalivap-7 (NlSP7) were identified as potential planthopper-specific gelling saliva components, but their biological functions remain unknown. RESULTS: Here, we showed by transcriptomic analyses that NlSP5 and NlSP7 were biasedly expressed in the salivary glands of BPHs. Using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated genome-editing system, we constructed NlSP5 and NlSP7 homozygous mutants (NlSP5-/- and NlSP7-/-). Electrical penetration graph assay showed that NlSP5-/- and NlSP7-/- mutants exhibited abnormal probing and feeding behaviors. Bioassays revealed that the loss-of-function of NlSP5 and NlSP7 significantly reduced the fitness of BPHs, with extended developmental duration, shortened lifespan, reduced weight, and impaired fecundity and hatching rates. CONCLUSION: These findings deepen our understanding of the BPH-host interaction and may provide potential targets for the management of rice planthoppers. © 2024 Society of Chemical Industry.

5.
Int J Biol Macromol ; 266(Pt 2): 131330, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570003

RESUMO

The challenge of drug resistance in bacteria caused by the over use of biotics is increasing during the therapy process, which has attracted great attentions of the clinicians and scientists around the world. Recently, photodynamic therapy (PDT) triggered by photosensitizer (PS) has become a promising treatment method because of its high efficacy, easy operation, and low side effect. Herein, the poly-l-lysine (PLL) modified metal-organic framework (MOF) nanoparticles, ZIF/PLL-CIP/CUR, were synthesized to allow both reactive oxygen species (ROS) responsive drug release and photodynamic effect for synergistic therapy against drug resistant bacterial infections. The PLL was modified on the shell of the zeolite imidazole framework (ZIF) by the ROS-responsive thioketal linker for controllable CIP release. CUR were encapsulated in ZIF as the photosensitizer for blue light mediated photodynamic effect to produce singlet oxygen (1O2) and superoxide anion radical (O2-) for efficient inhibition towards methicillin-resistant Staphylococcus aureus (MRSA). The charge conversion from negative charge (-4.6 mV) to positive charge (2.6 mV) was observed at pH 7.4 and pH 5.5, and 70.9 % CIP was found released at pH 5.5 in the presence of H2O2, which suggests the good biosafety at physiological pH and ROS-responsive drug release of the as-prepared nanoparticle in the bacterial microenvironment. The as-prepared nanoparticles could effectively kill MRSA and disrupt bacterial biofilm by combination of chemo- and photodynamic therapy. In mice model, the as-prepared nanoparticles exhibited excellent biosafety and synergistic effect with 98.81 % healing rate in treatment of MRSA infection, which is considered as a promising candidate in combating drug resistant bacterial infection.


Assuntos
Estruturas Metalorgânicas , Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Polilisina , Espécies Reativas de Oxigênio , Polilisina/química , Polilisina/farmacologia , Fotoquimioterapia/métodos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Animais , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Concentração de Íons de Hidrogênio , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Liberação Controlada de Fármacos , Curcumina/farmacologia , Curcumina/química , Infecções Estafilocócicas/tratamento farmacológico
6.
Fitoterapia ; 175: 105909, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38479615

RESUMO

Artemdubosides A-E (1-5), the first examples of natural polyacetylenes substituted by 6'-O-crotonyl ß-glucopyranoside, and artemdubosides F-G (6-7) that were two unusual polyacetylenes featuring a 6'-O-acetyl ß-glucopyranoside moiety, were isolated from Artemisia dubia var. subdigitata. Their structures were elucidated based on the spectral data including HRESIMS, UV, IR, 1D and 2D NMR, and ECD calculations. Antihepatoma assay suggested that compound 1 exhibited activity against HepG2, Huh7, and SK-Hep-1 cells with inhibitory ratios of 77.1%, 90.8%, and 73.1% at 200.0 µM, respectively.

7.
Materials (Basel) ; 17(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38541530

RESUMO

In order to examine the mechanical properties and rotational bending fatigue performance of 40CrNi2MoE steel subsequent to tempering at varying temperatures, the steel specimen was subjected to tempering within the range of 400~460 °C. SEM, EBSD, and TEM were used to analyze the microstructure as well as precipitates. The strain hardening law was studied using the modified Crussard-Jaoult method. Investigations were undertaken to reveal the rotational bending fatigue life with respect to the tempering temperature. The findings indicate that the strength and fatigue life of the examined steels exhibit a decline as the tempering temperature increases, with the primary factor affecting this trend being the alteration in dislocation density. No notable impact on the fatigue fracture morphology exerted by tempering temperature was found within the range of the experiment. The C-J model analysis reveals that the work-hardening behavior of the trial steels is influenced by dislocations and the second phase.

8.
Nat Commun ; 15(1): 2797, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555355

RESUMO

Silent information regulator 2 (Sir2) proteins typically catalyze NAD+-dependent protein deacetylation. The recently identified bacterial Sir2 domain-containing protein, defense-associated sirtuin 2 (DSR2), recognizes the phage tail tube and depletes NAD+ to abort phage propagation, which is counteracted by the phage-encoded DSR anti-defense 1 (DSAD1), but their molecular mechanisms remain unclear. Here, we determine cryo-EM structures of inactive DSR2 in its apo form, DSR2-DSAD1 and DSR2-DSAD1-NAD+, as well as active DSR2-tube and DSR2-tube-NAD+ complexes. DSR2 forms a tetramer with its C-terminal sensor domains (CTDs) in two distinct conformations: CTDclosed or CTDopen. Monomeric, rather than oligomeric, tail tube proteins preferentially bind to CTDclosed and activate Sir2 for NAD+ hydrolysis. DSAD1 binding to CTDopen allosterically inhibits tube binding and tube-mediated DSR2 activation. Our findings provide mechanistic insight into DSR2 assembly, tube-mediated DSR2 activation, and DSAD1-mediated inhibition and NAD+ substrate catalysis in bacterial DSR2 anti-phage defense systems.


Assuntos
Sirtuínas , Sirtuínas/metabolismo , NAD/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Sirtuína 2 , Hidrólise
9.
World J Gastroenterol ; 30(4): 346-366, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38313238

RESUMO

BACKGROUND: Extreme heat exposure is a growing health problem, and the effects of heat on the gastrointestinal (GI) tract is unknown. This study aimed to assess the incidence of GI symptoms associated with heatstroke and its impact on outcomes. AIM: To assess the incidence of GI symptoms associated with heatstroke and its impact on outcomes. METHODS: Patients admitted to the intensive care unit (ICU) due to heatstroke were included from 83 centres. Patient history, laboratory results, and clinically relevant outcomes were recorded at ICU admission and daily until up to day 15, ICU discharge, or death. GI symptoms, including nausea/vomiting, diarrhoea, flatulence, and bloody stools, were recorded. The characteristics of patients with heatstroke concomitant with GI symptoms were described. Multivariable regression analyses were performed to determine significant predictors of GI symptoms. RESULTS: A total of 713 patients were included in the final analysis, of whom 132 (18.5%) patients had at least one GI symptom during their ICU stay, while 26 (3.6%) suffered from more than one symptom. Patients with GI symptoms had a significantly higher ICU stay compared with those without. The mortality of patients who had two or more GI symptoms simultaneously was significantly higher than that in those with one GI symptom. Multivariable logistic regression analysis revealed that older patients with a lower GCS score on admission were more likely to experience GI symptoms. CONCLUSION: The GI manifestations of heatstroke are common and appear to impact clinically relevant hospitalization outcomes.


Assuntos
Gastroenteropatias , Golpe de Calor , Humanos , Estudos Retrospectivos , Estado Terminal , Gastroenteropatias/epidemiologia , Gastroenteropatias/etiologia , Unidades de Terapia Intensiva , Golpe de Calor/complicações , Golpe de Calor/epidemiologia
10.
World J Gastroenterol ; 30(3): 225-237, 2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38314132

RESUMO

This comprehensive review elucidates the complex interplay between gut microbiota and constipation in Parkinson's disease (PD), a prevalent non-motor symptom contributing significantly to patients' morbidity. A marked alteration in the gut microbiota, predominantly an increase in the abundance of Proteobacteria and Bacteroidetes, is observed in PD-related constipation. Conventional treatments, although safe, have failed to effectively alleviate symptoms, thereby necessitating the development of novel therapeutic strategies. Microbiological interventions such as prebiotics, probiotics, and fecal microbiota transplantation (FMT) hold therapeutic potential. While prebiotics improve bowel movements, probiotics are effective in enhancing stool consistency and alleviating abdominal discomfort. FMT shows potential for significantly alleviating constipation symptoms by restoring gut microbiota balance in patients with PD. Despite promising developments, the causal relationship between changes in gut microbiota and PD-related constipation remains elusive, highlighting the need for further research in this expanding field.


Assuntos
Doença de Parkinson , Probióticos , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/terapia , Doença de Parkinson/microbiologia , Constipação Intestinal/etiologia , Constipação Intestinal/terapia , Transplante de Microbiota Fecal/efeitos adversos , Prebióticos , Probióticos/uso terapêutico
11.
PLoS One ; 19(2): e0293135, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38315677

RESUMO

Since its initial discovery in the Hunan province of China, genomic DNA of porcine circovirus 4 (PCV4) has been detected in pigs across multiple provinces in China, as well as in South Korea. However, the prevalence of porcine circovirus type 4 in Gansu Province, China, remains unknown. To address this gap, we undertook an extensive study where we gathered 121 clinical samples displaying diverse clinical manifestations from pig farms in Gansu Province between 2022 and 2023. Employing a real-time fluorescence quantification method, we identified the presence of PCV4 genome. Out of the 121 clinical samples analyzed, 13 samples tested positive for PCV4, resulting in a positive rate of 10.74% (13/121). This finding confirms the presence of PCV4 in pig farms within Gansu Province, China. Furthermore, we successfully sequenced and analyzed the complete genomes of two distinct PCV4 strains, comparing them with 60 reference sequences archived in the GenBank database. The results revealed a high nucleotide homology (98.2-98.8%) between the strains obtained in this study and the PCV4 reference strains, indicating a relatively low evolutionary rate of the PCV4 genome. Phylogenetic analysis revealed that two strains in this study belong to PCV4a and PCV4c. As far as we know, this study marks the inaugural report on the molecular identification and genomic attributes of PCV4 in Gansu Province, China, offering valuable insights for devising preventive and control strategies against this emerging virus.


Assuntos
Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Suínos , Animais , Filogenia , Circovirus/genética , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Doenças dos Suínos/epidemiologia , China/epidemiologia
12.
Theranostics ; 14(3): 1029-1048, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250044

RESUMO

Bacterial infections remain a formidable threat to human health, a situation exacerbated by the escalating problem of antibiotic resistance. While alternative antibacterial strategies such as oxidants, heat treatments, and metal nanoparticles (NPs) have shown potential, they come with significant drawbacks, ranging from non-specificity to potential environmental concerns. In the face of these challenges, the rapid evolution of micro/nanomotors (MNMs) stands out as a revolutionary development in the antimicrobial arena. MNMs harness various forms of energy and convert it into a substantial driving force, offering bright prospects for combating microbial threats. MNMs' mobility allows for swift and targeted interaction with bacteria, which not only improves the carrying potential of therapeutic agents but also narrows the required activation range for non-drug antimicrobial interventions like photothermal and photodynamic therapies, substantially improving their bacterial clearance rates. In this review, we summarized the diverse propulsion mechanisms of MNMs employed in antimicrobial applications and articulated their multiple functions, which include direct bactericidal action, capture and removal of microorganisms, detoxification processes, and the innovative detection of bacteria and associated toxins. Despite MNMs' potential to revolutionize antibacterial research, the translation from laboratory to clinical use remains challenging. Based on the current research status, we summarized the potential challenges and possible solutions and also prospected several key directions for future studies of MNMs for antimicrobial purposes. Collectively, by highlighting the important knowns and unknowns of antimicrobial MNMs, our present review would help to light the way forward for the field of antimicrobial MNMs and prevent unnecessary blindness and detours.


Assuntos
Hipertermia Induzida , Nanopartículas Metálicas , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cegueira , Taxa de Depuração Metabólica
13.
Nature ; 625(7994): 270-275, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38200301

RESUMO

Supersolid, an exotic quantum state of matter that consists of particles forming an incompressible solid structure while simultaneously showing superfluidity of zero viscosity1, is one of the long-standing pursuits in fundamental research2,3. Although the initial report of 4He supersolid turned out to be an artefact4, this intriguing quantum matter has inspired enthusiastic investigations into ultracold quantum gases5-8. Nevertheless, the realization of supersolidity in condensed matter remains elusive. Here we find evidence for a quantum magnetic analogue of supersolid-the spin supersolid-in the recently synthesized triangular-lattice antiferromagnet Na2BaCo(PO4)2 (ref. 9). Notably, a giant magnetocaloric effect related to the spin supersolidity is observed in the demagnetization cooling process, manifesting itself as two prominent valley-like regimes, with the lowest temperature attaining below 100 mK. Not only is there an experimentally determined series of critical fields but the demagnetization cooling profile also shows excellent agreement with the theoretical simulations with an easy-axis Heisenberg model. Neutron diffractions also successfully locate the proposed spin supersolid phases by revealing the coexistence of three-sublattice spin solid order and interlayer incommensurability indicative of the spin superfluidity. Thus, our results reveal a strong entropic effect of the spin supersolid phase in a frustrated quantum magnet and open up a viable and promising avenue for applications in sub-kelvin refrigeration, especially in the context of persistent concerns about helium shortages10,11.

14.
IEEE Trans Med Imaging ; 43(4): 1476-1488, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38048240

RESUMO

Accurate vascular segmentation from High Resolution 3-Dimensional (HR3D) medical scans is crucial for clinicians to visualize complex vasculature and diagnose related vascular diseases. However, a reliable and scalable vessel segmentation framework for HR3D scans remains a challenge. In this work, we propose a High-resolution Energy-matching Segmentation (HrEmS) framework that utilizes deep learning to directly process the entire HR3D scan and segment the vasculature to the finest level. The HrEmS framework introduces two novel components. Firstly, it uses the real-order total variation operator to construct a new loss function that guides the segmentation network to obtain the correct topology structure by matching the energy of the predicted segment to the energy of the manual label. This is different from traditional loss functions such as dice loss, which matches the pixels between predicted segment and manual label. Secondly, a curvature-based weight-correction module is developed, which directs the network to focus on crucial and complex structural parts of the vasculature instead of the easy parts. The proposed HrEmS framework was tested on three in-house multi-center datasets and three public datasets, and demonstrated improved results in comparison with the state-of-the-art methods using both topology-relevant and volumetric-relevant metrics. Furthermore, a double-blind assessment by three experienced radiologists on the critical points of the clinical diagnostic processes provided additional evidence of the superiority of the HrEmS framework.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
15.
Nat Chem Biol ; 20(4): 503-511, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37932528

RESUMO

Argonaute proteins (Agos), which use small RNAs or DNAs as guides to recognize complementary nucleic acid targets, mediate RNA silencing in eukaryotes. In prokaryotes, Agos are involved in immunity: the short prokaryotic Ago/TIR-APAZ (SPARTA) immune system triggers cell death by degrading NAD+ in response to invading plasmids, but its molecular mechanisms remain unknown. Here we used cryo-electron microscopy to determine the structures of inactive monomeric and active tetrameric Crenotalea thermophila SPARTA complexes, revealing mechanisms underlying SPARTA assembly, RNA-guided recognition of target single-stranded DNA (ssDNA) and subsequent SPARTA tetramerization, as well as tetramerization-dependent NADase activation. The small RNA guides Ago to recognize its ssDNA target, inducing SPARTA tetramerization via both Ago- and TIR-mediated interactions and resulting in a two-stranded, parallel, head-to-tail TIR rearrangement primed for NAD+ hydrolysis. Our findings thus identify the molecular basis for target ssDNA-mediated SPARTA activation, which will facilitate the development of SPARTA-based biotechnological tools.


Assuntos
DNA de Cadeia Simples , NAD+ Nucleosidase , NAD , Microscopia Crioeletrônica , RNA , Sistema Imunitário
16.
International Eye Science ; (12): 203-209, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1005381

RESUMO

AIM: To observe the changes of macular retinal structure and microcirculation in patients with pituitary adenoma(PA)by optical coherence tomography(OCT)and optical coherence tomography angiography(OCTA).METHODS: Cross-sectional study. A total of 40 PA patients treated at the department of neurosurgery, Affiliated Hospital of Guangdong Medical University from September 2021 to March 2023 were included as PA group, and 42 age- and gender-matched healthy volunteers were selected as normal control group. All patients underwent visual field, OCT and OCTA examinations, and the correlation of ocular parameters in PA patients was analyzed.RESULTS:The vessel density(VD)of each retinal layer in the macular area of the PA group was lower than that of the normal control group, and the superficial vascular complex(SVC)-VD in the macular area was positively correlated with the thickness of the macular ganglion cell complex(mGCC)(except the nasal side of the inner ring and the lower part of the outer ring; P<0.05). The thickness of mGCC in each quadrant of the macular area and the thickness of the circumpapillary retinal nerve fiber layer(CP-RNFL)in each quadrant were negatively correlated with the mean defect(MD)value of the visual field(P<0.05), and the area of the foveal avascular zone(FAZ)was positively correlated with the MD value(P<0.05).CONCLUSION:The combination of OCT and OCTA can fully understand the microscopic changes of retinal structure and microcirculation function in PA patients, which is of great value in evaluating the preoperative visual function of PA patients.

17.
Org Lett ; 26(1): 12-17, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38127552

RESUMO

A versatile Co(III)-catalyzed C6-selective C-H activation/pyridine migration of 2-pyridones with available propiolates as coupling partners was demonstrated. This method features high atom economy, excellent regioselectivity, and good functional group tolerance by employing an inexpensive Co(III) catalyst under mild reaction conditions. Moreover, gram-scale synthesis and late-stage modifications of pharmaceuticals were performed to prove the effectiveness of these synthetic approaches.

18.
Eur J Med Chem ; 264: 116039, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38103540

RESUMO

P-glycoprotein (P-gp) is an important factor leading to multidrug resistance (MDR) in cancer treatment. The co-administration of anticancer drugs and P-gp inhibitors has been a treatment strategy to overcome MDR. In recent years, tyrosine kinase inhibitor Lapatinib has been reported to reverse MDR through directly interacting with ABC transporters. In this work, a series of P-gp inhibitors (1-26) was designed and synthesized by integrating the quinazoline core of Lapatinib into the molecule framework of the third-generation P-gp inhibitor Tariquidar. Among them, compound 14 exhibited better MDR reversal activity than Tariquidar. The docking results showed compound 14 displayed the L-shaped molecular conformation. Importantly, compound 14 increased the accumulation of Adriamycin (ADM) and rhodamine 123 (Rh123) in MCF7/ADM cells. Besides, compound 14 significantly increased ADM-induced apoptosis and inhibited the proliferation, migration and invasion of MCF7/ADM cells. It was also demonstrated that compound 14 significantly inhibited the growth of MCF7/ADM xenograft tumors by increasing the sensitivity of ADM. In summary, compound 14 has the potential to overcome MDR caused by P-gp.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Antineoplásicos , Humanos , Lapatinib , Resistencia a Medicamentos Antineoplásicos , Resistência a Múltiplos Medicamentos , Antineoplásicos/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Doxorrubicina/farmacologia , Benzamidas/farmacologia
19.
Sensors (Basel) ; 23(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38067757

RESUMO

The inability to locate device faults quickly and accurately has become prominent due to the large number of communication devices and the complex structure of secondary circuit networks in smart substations. Traditional methods are less efficient when diagnosing secondary equipment faults in smart substations, and deep learning methods have poor portability, high learning sample costs, and often require retraining a model. Therefore, a secondary equipment fault diagnosis method based on a graph attention network is proposed in this paper. All fault events are automatically represented as graph-structured data based on the K-nearest neighbors (KNNs) algorithm in terms of the feature information exhibited by the corresponding detection nodes when equipment faults occur. Then, a fault diagnosis model is established based on the graph attention network. Finally, partial intervals of a 220 kV intelligent substation are taken as an example to compare the fault localization effect of different methods. The results show that the method proposed in this paper has the advantages of higher localization accuracy, lower learning cost, and better robustness than the traditional machine learning and deep learning methods.

20.
Entropy (Basel) ; 25(12)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38136449

RESUMO

With the development of mobile applications, location-based services (LBSs) have been incorporated into people's daily lives and created huge commercial revenues. However, when using these services, people also face the risk of personal privacy breaches due to the release of location and query content. Many existing location privacy protection schemes with centralized architectures assume that anonymous servers are secure and trustworthy. This assumption is difficult to guarantee in real applications. To solve the problem of relying on the security and trustworthiness of anonymous servers, we propose a Geohash-based location privacy protection scheme for snapshot queries. It is named GLPS. On the user side, GLPS uses Geohash encoding technology to convert the user's location coordinates into a string code representing a rectangular geographic area. GLPS uses the code as the privacy location to send check-ins and queries to the anonymous server and to avoid the anonymous server gaining the user's exact location. On the anonymous server side, the scheme takes advantage of Geohash codes' geospatial gridding capabilities and GL-Tree's effective location retrieval performance to generate a k-anonymous query set based on user-defined minimum and maximum hidden cells, making it harder for adversaries to pinpoint the user's location. We experimentally tested the performance of GLPS and compared it with three schemes: Casper, GCasper, and DLS. The experimental results and analyses demonstrate that GLPS has a good performance and privacy protection capability, which resolves the reliance on the security and trustworthiness of anonymous servers. It also resists attacks involving background knowledge, regional centers, homogenization, distribution density, and identity association.

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