Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Mais filtros

País/Região como assunto
Ano de publicação
Intervalo de ano de publicação
1.
Cell ; 187(12): 2969-2989.e24, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38776919

RESUMO

The gut fungal community represents an essential element of human health, yet its functional and metabolic potential remains insufficiently elucidated, largely due to the limited availability of reference genomes. To address this gap, we presented the cultivated gut fungi (CGF) catalog, encompassing 760 fungal genomes derived from the feces of healthy individuals. This catalog comprises 206 species spanning 48 families, including 69 species previously unidentified. We explored the functional and metabolic attributes of the CGF species and utilized this catalog to construct a phylogenetic representation of the gut mycobiome by analyzing over 11,000 fecal metagenomes from Chinese and non-Chinese populations. Moreover, we identified significant common disease-related variations in gut mycobiome composition and corroborated the associations between fungal signatures and inflammatory bowel disease (IBD) through animal experimentation. These resources and findings substantially enrich our understanding of the biological diversity and disease relevance of the human gut mycobiome.


Assuntos
Fungos , Microbioma Gastrointestinal , Micobioma , Animais , Humanos , Masculino , Camundongos , Fezes/microbiologia , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Genoma Fúngico/genética , Genômica , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/genética , Metagenoma , Filogenia , Feminino , Adulto , Pessoa de Meia-Idade
2.
J Am Chem Soc ; 146(31): 21428-21441, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39051926

RESUMO

A Minisci-type borylation of unprotected adenosine, adenine nucleotide, and adenosine analogues was successfully achieved through photocatalysis or thermal activation. Despite the challenges posed by the presence of two potential reactive sites (C2 and C8) in the purine motif, the unique nucleophilic amine-ligated boryl radicals effortlessly achieved excellent C2 site selectivity and simultaneously avoided the formation of multifunctionalized products. This protocol proved effective for the late-stage borylation of some important biomolecules as well as a few antiviral and antitumor drug molecules, such as AMP, cAMP, Vidarabine, Cordycepin, Tenofovir, Adefovir, GS-441524, etc. Theoretical calculations shed light on the site selectivity, revealing that the free energy barriers for the C2-Minisci addition are further lowered through the chelation of additive Mg2+ to N3 and furyl oxygen. This phenomenon has been confirmed by an IGMH analysis. Preliminary antitumor evaluation, derivation of the C2-borylated adenosine to other analogues with high-value functionalities, along with the CuAAC click reactions, suggest the potential application of this methodology in drug molecular optimization studies and chemical biology.


Assuntos
Adenina , Adenosina , Adenosina/química , Adenosina/análogos & derivados , Adenina/química , Adenina/análogos & derivados , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Humanos , Estereoisomerismo , Estrutura Molecular , Antivirais/química , Antivirais/síntese química
3.
Cancer ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926891

RESUMO

BACKGROUND: Phosphatidylinositol 3-kinase (PI3K) inhibitors transformed management of various malignancies. This study preclinically characterized TQ-B3525 (dual PI3Kα/δ inhibitor) and assessed the recommended phase 2 dose (RP2D), safety, efficacy, and pharmacokinetics in relapsed or refractory (R/R) lymphoma or advanced solid tumors (STs). METHODS: Oral TQ-B3525 was given at eight dose levels on a 28-day cycle. Primary end points were dose-limiting toxicity (DLT), maximum tolerated dose (MTD), and safety. RESULTS: TQ-B3525 showed high selectivity and suppressed tumor growth. Between June 12, 2018, and November 18, 2020, 80 patients were enrolled (63 in dose-escalation cohort; 17 in dose-expansion cohort). Two DLTs occurred in two (two of 63, 3.2%) DLT-evaluable patients; MTD was not identified. TQ-B3525 at 20 mg once daily was selected as RP2D. Grade 3 or worse treatment-related adverse events mainly included hyperglycemia (16.3%), neutrophil count decreased (15.0%), and diarrhea (10.0%). Two (2.5%) treatment-related deaths were reported. Sixty patients with R/R lymphoma and 11 advanced STs demonstrated objective response rates of 68.3% and 9.1%, disease control rates of 91.7% and 54.6%, median progression-free survivals of 12.1 and 1.1 months; median overall survivals were not reached. CONCLUSION: TQ-B3525 exhibited rapid absorption and a nearly proportional increase in exposure. Acceptable safety and promising efficacy support further investigation of TQ-B3525 (20 mg once daily) for R/R lymphoma.

4.
Small ; 20(32): e2311249, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38482932

RESUMO

Host-guest catalyst provides new opportunities for targeted applications and the development of new strategies for preparing host-guest catalysts is highly desired. Herein, an in situ solvent-free approach is developed for implanting ZrW2O7(OH)2(H2O)2 nanorods (ZrW-NR) in nitro-functionalized UiO-66(Zr) (UiO-66(Zr)-NO2) with hierarchical porosity, and the encapsulation of ZrW-NR enables the as-prepared host-guest catalyst remarkably enhanced catalytic performance for both for oxidative desulfurization (ODS) and acetalization reactions. ZrW-NR@UiO-66(Zr)-NO2 can eliminate 500 ppm sulfur within 9 min at 40 °C in ODS, and can transform 5.6 mmol benzaldehyde after 3 min at room temperature in acetalization reaction. Its turnover frequencies reach 72.3 h-1 at 40 °C for ODS which is 33.4 times higher than UiO-66(Zr)-NO2, and 28140 h-1 for acetalization which is the highest among previous reports. Density functional theory calculation result indicates that the W sites in ZrW-NR can decompose H2O2 to WVI-peroxo intermediates that contribute to catalytic activity for the ODS reaction. This work opens a new solvent-free approach for preparing MOFs-based host-guest catalysts to upgrade their redox and acid performance.

5.
Ann Hematol ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012515

RESUMO

INTRODUCTION: Lymphoma tissue biopsies cannot fully capture genetic features due to accessibility and heterogeneity. We aimed to assess the applicability of circulating tumor DNA (ctDNA) for genomic profiling and disease surveillance in classic Hodgkin lymphoma (cHL), primary mediastinal large B-cell lymphoma (PMBCL), and diffuse large B-cell lymphoma (DLBCL). METHODS: Tumor tissue and/or liquid biopsies of 49 cHLs, 32 PMBCLs, and 74 DLBCLs were subject to next-generation sequencing targeting 475 genes. The concordance of genetic aberrations in ctDNA and paired tissues was investigated, followed by elevating ctDNA-based mutational landscapes and the correlation between ctDNA dynamics and radiological response/progression. RESULTS: ctDNA exhibited high concordance with tissue samples in cHL (78%), PMBCL (84%), and DLBCL (78%). In cHL, more unique mutations were detected in ctDNA than in tissue biopsies (P < 0.01), with higher variant allele frequencies (P < 0.01). Distinct genomic features in cHL, PMBCL, and DLBCL, including STAT6, SOCS1, BTG2, and PIM1 alterations, could be captured by ctDNA alone. Prevalent PD-L1/PD-L2 amplifications were associated with more concomitant alterations in PMBCL (P < 0.01). Moreover, ctDNA fluctuation could reflect treatment responses and indicate relapse before imaging diagnosis. CONCLUSIONS: Lymphoma genomic profiling by ctDNA was concordant with that by tumor tissues. ctDNA might also be applied in lymphoma surveillance.

6.
Langmuir ; 40(32): 17124-17133, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39080259

RESUMO

Problems such as bacterial resistance caused by tetracycline antibiotics pose a serious threat to human production and life and ecosystems. We prepared ZnFe2O4@ZnWO4 heterojunction nanocomposites using hydrothermal and coprecipitation methods. The micromorphology, structure, and photoelectrochemical properties were analyzed. In combination with the presence of H2O2, the photo-Fenton activity of the antibiotic tetracycline at high concentration was tested under visible light irradiation, and its catalytic mechanism was investigated. The results showed that the composition of the composite heterojunction improved the catalytic activity of the catalyst. At a pollutant concentration of 50 mg L-1 and pH 5, 30% ZnWO4/ZnFe2O4 degraded 92.1% of tetracycline in 60 min with a degradation rate of 0.0295 min-1, which was 6.7 times higher than that of pure ZnFe2O4. The results of free radical trapping experiments and electron spin resonance techniques indicated that hydroxyl radical (•OH) and superoxide radical (O2-) played important roles in the photo-Fenton degradation of tetracycline. Notably, the catalyst maintained a high degradation rate (80%) after five cycles. ZnFe2O4 introduced in this article may provide a promising strategy for achieving strong light absorption and is authoritative in meeting future environmental requirements.

7.
Mol Cell Biochem ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720056

RESUMO

Gastric cancer (GC) stands as one of the most formidable malignancies worldwide. It is well-established that miRNAs play a crucial role in the initiation and progression of various human cancers. Among these, miR-99a-3p has been implicated in the pathogenesis of GC. In the context of our study, we embarked on the comprehensive examination of miR-99a-3p expression in GC cells. Additionally, we sought to establish a correlation between miR-99a-3p expression levels and the overall survival (OS) of GC patients, and our findings hinted at its potential role in predicting an unfavorable prognosis. To further investigate the functional implications of miR-99a-3p in GC, we conducted a series of cell-based experiments after successfully knocking down miR-99a-3p. These investigations uncovered a substantial inhibition of cellular events associated with tumor progression. Moreover, employing TargetScan, we identified Tripartite motif-containing protein 21 (TRIM21) as a putative target with a binding site for miR-99a-3p. Subsequent dual-luciferase reporter gene assay confirmed the direct interaction between miR-99a-3p and TRIM21. Western blot analysis validated the alteration in TRIM21 expression levels, revealing an upregulation upon miR-99a-3p knockdown. Building on these molecular findings, we extended our investigations to human GC tissues, where we observed a downregulation of TRIM21, which, notably, correlated with shorter overall survival. Lastly, to further solidify our conclusions, we conducted a series of in vitro and in vivo rescue experiments, collectively suggesting that miR-99a-3p promoted the progression of GC cells through the downregulation of TRIM21. In summary, our study comprehensively explored the role of miR-99a-3p in GC, revealing its association with unfavorable patient outcomes, functional implications in tumor progression, and a direct regulatory relationship with TRIM21. These findings collectively underscore the significance of miR-99a-3p in the pathogenesis of GC and present a potential therapeutic avenue for further investigation.

8.
J Org Chem ; 89(8): 5287-5297, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38568740

RESUMO

Instigated by olfactory analysis of odorant molecules, the constitutions of 3,4-dihydrocoumarins prepared by PIFA-based oxidative cyclizations of 3-arylpropionic acids were revised by means of 2D NMR and X-ray analysis. Supported by computational analysis, the migratory mechanism of intermediate spirolactonic cations has been amended: 1,2-alkyl shifts instead of 1,2-carboxylic shifts were selectively obtained.

9.
J Biopharm Stat ; : 1-21, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38180054

RESUMO

In clinical trials, unilateral or bilateral data can usually be encountered if a subject contributes one or both of paired organs. For the bilateral data, responses from two paired body parts are correlated. In this paper, we study various confidence intervals of common risk difference in stratified unilateral and bilateral data based on the Dallal's model. Simulation results show that the score method outperforms other methods and provides coverage probability close to the nominal level and satisfactory coverage width. Hence, the method is recommended. In addition, the inverse hyperbolic tangent Wald-type become as optimal as the score method with the increase of sample sizes. An otolaryngology example is used to demonstrate the proposed methods.

10.
J Stroke Cerebrovasc Dis ; 33(10): 107915, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39098364

RESUMO

BACKGROUND AND PURPOSE: Prior observational studies have suggested a strong correlation between sarcopenia and stroke, but the causal link between them remains uncertain. This study aims to investigate the associations between genetically predicted sarcopenia-related traits and stroke using a two-step Mendelian randomization (MR) approach. METHODS: Genome-wide association study (GWAS) summary data for sarcopenia-related traits were acquired from the UK Biobank. Genetic associations for ischemic stroke (IS) and its subtypes were selected from the MEGASTROKE consortium comprising European ancestry participants. GWAS summary data for cerebral hemorrhage were obtained from the FinnGen consortium, including intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH). MR estimates were calculated using the inverse-variance weighted (IVW) method. The robustness of results was assessed for heterogeneity and pleiotropy of individual single nucleotide polymorphisms (SNPs). RESULTS: Higher appendicular lean mass (ALM) exhibited a potential causal association with a reduced incidence of large artery atherosclerosis (LAA) (odds ratio [OR] = 0.81, 95% confidence interval [CI]:0.71-0.93; P = 0.003) and small vessel disease (SVD) (OR = 0.83, 95% CI:0.74-0.94; P = 0.002). The associations of ALM with IS and ICH were compromised after adjusting for body fat and physical activity with multivariable MR. Two-step MR mediation analysis explored 33 candidate mediators, among which hypertension and SBP accounted for more than 10% of the mediation proportion in the relationship between ALM and stroke and its subtypes. CONCLUSION: Our research findings indicate that lower ALM is associated with a increased risk of stroke . It is necessary to explore the specific protective mechanisms of higher ALM for preventing stroke occurrence.

11.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3657-3667, 2024 Jul.
Artigo em Zh | MEDLINE | ID: mdl-39041138

RESUMO

This study aims to predict the possible targets and related signaling pathways of Modified Huoluo Xiaoling Pills against colorectal cancer(CRC) by both network pharmacology and molecular docking and verify the mechanism of action by experiments. TCMSP was used to obtain the active ingredients and targets of Modified Huoluo Xiaoling Pills, and GeneCards, DrugBank, OMIM, and TTD were employed to acquire CRC-related targets. Cytoscape software was utilized to construct the drug-active ingredient-target network, and the STRING database was applied to establish the protein-protein interaction(PPI) network. DAVID platform was adopted to investigate the targets in terms of GO function and KEGG pathway enrichment analysis. Molecular docking was performed in AutoDock Vina. HCT 116 cells were intervened by different concentrations of Modified Huoluo Xiaoling Pills-containing serum, and CCK-8 was used to detect the proliferation inhibition of HCT 116 cells in each group. Transwell was employed to show the invasive abi-lity of HCT 116 cells, and Western blot was taken to reveal the expression levels of ß-catenin, cyclinD1, c-Myc, as well as epithelial-mesenchymal transition(EMT) marker proteins E-cadherin, N-cadherin, vimentin, MMP2, MMP7, MMP9, and TWIST in HCT 116 cells. The network pharmacological analysis yielded 242 active ingredients of Modified Huoluo Xiaoling Pills, 1 844 CRC targets, and 127 overlapping targets of CRC and Modified Huoluo Xiaoling Pills, and the signaling pathways related to CRC involved PI3K-Akt, TNF, HIF-1, IL-17, Wnt, etc. Molecular docking showed that the key active ingredients had a stable binding conformation with the core proteins. CCK-8 indicated that Modified Huoluo Xiaoling Pills significantly inhibited the proliferation of HCT 116 cells. Transwell assay showed that with increasing concentration of Modified Huoluo Xiaoling Pills containing serum, the invasive ability of HCT 116 cells was more obviously inhibited. The expression of ß-catenin, cyclinD1, c-Myc, N-cadherin, vimentin, MMP2, MMP7, MMP9, and TWIST proteins were suppressed, and the expression of E-cadherin was improved by the intervention of drug-containing serum. Thus, it can be seen that Modified Huoluo Xiaoling Pills restrains the proliferation, invasion, and metastasis of CRC cells through multiple components, multiple targets, and multiple pathways, and the mechanism of action may be related to the inhibition of the activation of the Wnt/ß-catenin signaling pathway, thereby affecting the occurrence of EMT.


Assuntos
Proliferação de Células , Neoplasias Colorretais , Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Farmacologia em Rede , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Proliferação de Células/efeitos dos fármacos , Células HCT116 , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
12.
Angew Chem Int Ed Engl ; 63(6): e202310905, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38100193

RESUMO

Electrolytes that can keep liquid state are one of the most important physical metrics to ensure the ions transfer with stable operation of rechargeable lithium-based batteries at a wide temperature window. It is generally accepted that strong polar solvents with high melting points favor the safe operation of batteries above room temperatures but are susceptible to crystallization at low temperatures (≤-40 °C). Here, a crystallization limitation strategy was proposed to handle this issue. We demonstrate that, although the high melting points of ethylene sulfite (ES, -17 °C) and fluoroethylene carbonate (FEC, ≈23 °C), their mixtures can avoid crystallization at low temperatures, which can be attributed to low intermolecular interactions and altered molecular motion dynamics. A suitable ES/FEC ratio (10 % FEC) can balance the bulk and interface transport of ions, enabling LiNi0.8 Mn0.1 Co0.1 O2 ||lithium (NCM811||Li) full cells to deliver excellent temperature resilience and cycling stability over a wide temperature range from -50 °C to +70 °C. More than 66 % of the capacity retention was achieved at -50 °C compared to room temperature. The NCM811||Li pouch cells exhibit high cycling stability under realistic conditions (electrolyte weight to cathode capacity ratio (E/C)≤3.5 g Ah-1 , negative to positive electrode capacity ratio (N/P)≤1.09) at different temperatures.

13.
Math Biosci Eng ; 21(4): 5283-5307, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38872536

RESUMO

The novel coronavirus disease (COVID-19) pandemic has profoundly impacted the global economy and human health. The paper mainly proposed an improved susceptible-exposed-infected-recovered (SEIR) epidemic model with media coverage and limited medical resources to investigate the spread of COVID-19. We proved the positivity and boundedness of the solution. The existence and local asymptotically stability of equilibria were studied and a sufficient criterion was established for backward bifurcation. Further, we applied the proposed model to study the trend of COVID-19 in Shanghai, China, from March to April 2022. The results showed sensitivity analysis, bifurcation, and the effects of critical parameters in the COVID-19 model.


Assuntos
COVID-19 , Pandemias , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , China/epidemiologia , Meios de Comunicação de Massa , Simulação por Computador , Algoritmos
14.
Cell Regen ; 13(1): 13, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918264

RESUMO

F-box proteins play essential roles in various cellular processes of spermatogenesis by means of ubiquitylation and subsequent target protein degradation. They are the substrate-recognition subunits of SKP1-cullin 1-F-box protein (SCF) E3 ligase complexes. Dysregulation of F­box protein­mediated proteolysis could lead to male infertility in humans and mice. The emerging studies revealed the physiological function, pathological evidence, and biochemical substrates of F-box proteins in the development of male germ cells, which urging us to review the current understanding of how F­box proteins contribute to spermatogenesis. More functional and mechanistic study will be helpful to define the roles of F-box protein in spermatogenesis, which will pave the way for the logical design of F-box protein-targeted diagnosis and therapies for male infertility, as the spermatogenic role of many F-box proteins remains elusive.

15.
Health Place ; 85: 103176, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38244248

RESUMO

Running activity is closely related to the urban built environment in terms of mental and physical health, and this relationship can change as a result of spatio-temporal changes. Most studies, however, do not account for this and assume a linear relationship exists between the built environment and running activity. This study, therefore, collected running data spanning 2019-2022, studied spatial distribution of four-year running activity, established built environment indicators, used a random forest approach to investigate the non-linear relationship between them, and evaluated spatio-temporal changes in the relationships over time. The findings suggested that running activities are spatially clustered and the degree of clustering varies over time, and nonlinear relationships and threshold effects between the built environment and running activity can be found through the random forest algorithm and partial dependence plots. Urban park green space, greenway, and the normalized difference vegetation index had the most significant effects on running activity. The effects of population, buildings, streets, road intersections, and points of interest on running activity changed during the Coronavirus disease 2019 pandemic. In 2022, however, these effects were consistent with those during the pre-pandemic period. Our findings fill research gaps by using spatio-temporal analysis and a non-linear approach; they can also provide a reference for urban planners in building running-suitable and healthy cities.


Assuntos
Ambiente Construído , Algoritmo Florestas Aleatórias , Humanos , Cidades , China
16.
Elife ; 122024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470475

RESUMO

Spermiogenesis is a critical, post-meiotic phase of male gametogenesis, in which the proper gene expression is essential for sperm maturation. However, the underFlying molecular mechanism that controls mRNA expression in the round spermatids remains elusive. Here, we identify that FBXO24, an orphan F-box protein, is highly expressed in the testis of humans and mice and interacts with the splicing factors (SRSF2, SRSF3, and SRSF9) to modulate the gene alternative splicing in the round spermatids. Genetic mutation of FBXO24 in mice causes many abnormal splicing events in round spermatids, thus affecting a large number of critical genes related to sperm formation that were dysregulated. Further molecular and phenotypical analyses revealed that FBXO24 deficiency results in aberrant histone retention, incomplete axonemes, oversized chromatoid body, and abnormal mitochondrial coiling along sperm flagella, ultimately leading to male sterility. In addition, we discovered that FBXO24 interacts with MIWI and SCF subunits and mediates the degradation of MIWI via K48-linked polyubiquitination. Furthermore, we show that FBXO24 depletion could lead to aberrant piRNA production in testes, which suggests FBXO24 is required for normal piRNA counts. Collectively, these data demonstrate that FBXO24 is essential for sperm formation by regulating mRNA alternative splicing and MIWI degradation during spermiogenesis.


Assuntos
Processamento Alternativo , RNA de Interação com Piwi , Humanos , Masculino , Animais , Camundongos , Sêmen , Espermatozoides , Fertilidade , Fatores de Processamento de Serina-Arginina
17.
Sci Rep ; 14(1): 12040, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802498

RESUMO

This paper presents a frequency selective surface (FSS) with a wideband second-order bandpass response in the dual-band of microwave and millimeter wave. The overall structure consists of three layers of metal pattern and two layers of thin dielectric substrate. The top and bottom metal layers have capacitive patches with integrated curled Jerusalem cross slot resonators, while the intermediate metal layer has an inductive grid structure with cross-shaped slot resonators. The incorporated slot resonators play a pivotal role in achieving the desired transmission poles or zeros, which enable a wideband second-order filtering response in the dual-band and a quick roll-off at the passband edges, increasing the efficacy of electromagnetic shielding. To fully investigate the structure's frequency response, an equivalent circuit model of the structure is created, spanning the complete frequency range of 5-50 GHz. Physical samples are created and measured to confirm the suggested approach's efficacy. The passband center frequencies of the FSS are found at f1 = 19.42 GHz and f2 = 42.78 GHz, and the - 3 dB bandwidth is 4.34 GHz (17.25-21.59 GHz) and 8.54 GHz (38.51-47.05 GHz), respectively. The simulation results align well with the experimental data. The transmission response rapidly transitions from the passband to the stopband at the passband boundaries.

18.
ACS Biomater Sci Eng ; 10(2): 921-931, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38288701

RESUMO

Methotrexate (MTX), a primary treatment for moderate to severe psoriasis, is limited in clinical use due to suboptimal results and severe side effects from subcutaneous (SC) injection and oral administration. Microneedles offer a promising alternative for direct MTX delivery to targeted skin lesions, but issues such as drug wastage, dosage inaccuracy, and limited drug residence time in the lesions remain. This study introduces a tip-swellable microneedle array patch (TSMAP) using photo-cross-linked methacrylated hyaluronic acid (MeHA) and biocompatible resin for effective MTX loading and sustained delivery. A two-cast micromolding with vacuum drying is employed to concentrate cross-linked MeHA in about 30% of the needle's height at the tip, thereby ensuring that only the TSMAP tip swells. Efficient MTX loading into TSMAP tips is achieved through a 30 s drug solution immersion and 10 min drying, potentially minimizing drug waste from incomplete skin insertion due to skin elasticity. The MTX-loaded TSMAP effectively penetrates both porcine and psoriasis-like mouse skin with its tips detaching from the resin substrate and embedding deeply into the skin tissue, thereby functioning as a drug release reservoir. TSMAP significantly prolongs drug retention in skin compared with SC injection and dissolvable microneedles. The in vivo study demonstrates that TSMAP-mediated MTX delivery substantially enhances therapeutic outcomes in alleviating psoriasis symptoms and downregulating psoriasis-associated cytokines, outperforming oral administration, SC injection, and dissolvable microneedles. Thus, TSMAP could offer an efficient and user-friendly alternative for drug administration in the treatment of various skin diseases.


Assuntos
Metotrexato , Psoríase , Camundongos , Animais , Suínos , Metotrexato/uso terapêutico , Administração Cutânea , Sistemas de Liberação de Medicamentos/métodos , Pele , Psoríase/tratamento farmacológico
19.
Sci Rep ; 14(1): 9415, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658637

RESUMO

This work presents a novel tri-band bandpass frequency selective surface (FSS) that achieves high-order filtering responses in different frequency bands by means of a complementary structure. The proposed FSS is composed of three metal periodic arrays, which are separated by multilayer dielectric substrates. The gridded-double convoluted loop (G-DCL) structure, which is the middle layer structure, is a hybrid resonator that generates different resonant frequencies. The top and bottom layer structures are designed as complementary structures to the middle layer. To accurately describe the frequency responses, an equivalent circuit model (ECM) has been constructed over the entire band from 0 to 16 GHz. The results of the simulation indicate that the developed FSS can generate three pass-bands operating at 3.79 GHz, 8.34 GHz, and 12.52 GHz, respectively, and - 3 dB fractional bandwidths are 52.8%, 13.7%, and 19.7%. The transmission responses at the edges of each passband show a quick roll-off from the passband to the stopband, and there is significant out-of-band suppression between adjacent passbands. Moreover, the FSS maintains excellent angular and polarization stability within a 50° range. For verification, the tri-band FSS has been fabricated and tested. The experimental results match the simulation results, validating the accuracy of the FSS design.

20.
Nat Commun ; 15(1): 7199, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39169037

RESUMO

Materials with well-defined electrical resistivity that does not change with temperature or time are important in robotics, communication and automation. However, the challenge of designing such materials has remained elusive due to the temperature-dependent electron-phonon scattering. Moreover, resistive electrical conductors used in flexible and mobile systems under high mechanical loads must possess both high strength and ductility. Achieving such multi-properties presents a fundamental challenge. Here, we solve this problem by combining multicomponent alloy design with atomic-scale chemistry tuning. We term the resultant material 'Resinvar' alloy, due to its invariable resistivity (148 µΩ·cm) over wide temperature ranges from room temperature to 723 K. The alloy also has high tensile strength (948 MPa) at large tensile elongation (53%). The distorted lattice, chemical short-range order and ordered coherent nanoprecipitates in the material enable the invariant resistivity via promoting temperature-independent inelastic electron scattering, and contribute to the excellent strength-ductility synergy by manipulating dislocation slip.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA