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1.
ACS Nano ; 18(11): 7937-7944, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38441035

RESUMO

Strongly correlated states commonly emerge in twisted bilayer graphene (TBG) with "magic-angle" (1.1°), where the electron-electron (e-e) interaction U becomes prominent relative to the small bandwidth W of the nearly flat band. However, the stringent requirement of this magic angle makes the sample preparation and the further application facing great challenges. Here, using scanning tunneling microscopy (STM) and spectroscopy (STS), we demonstrate that the correlation-induced symmetry-broken states can also be achieved in a 3.45° TBG, via engineering this nonmagic-angle TBG into regimes of U/W > 1. We enhance the e-e interaction through controlling the microscopic dielectric environment by using a MoS2 substrate. Simultaneously, the width of the low-energy van Hove singularity (VHS) peak is reduced by enhancing the interlayer coupling via STM tip modulation. When partially filled, the VHS peak exhibits a giant splitting into two states flanked by the Fermi level and shows a symmetry-broken LDOS distribution with a stripy charge order, which confirms the existence of strong correlation effect in our 3.45° TBG. Our result demonstrates the feasibility of the study and application of the correlation physics in TBGs with a wider range of twist angle.

3.
Nanoscale ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546273

RESUMO

Two-dimensional (2D) chromium-based self-intercalated materials Cr1+nX2 (0 ≤ n ≤ 1, X = S, Se, Te) have attracted much attention because of their tunable magnetism with good environmental stability. Intriguingly, the magnetic and electrical properties of the materials can be effectively tuned by altering the coverage and spatial arrangement of the intercalated Cr (ic-Cr) within the van der Waals gap, contributing to different stoichiometries. Several different Cr1+nX2 systems have been widely investigated recently; however, those with the same stoichiometric ratio (such as Cr1.25Te2) were reported to exhibit disparate magnetic properties, which still lacks explanation. Therefore, a systematic in situ study of the mechanisms with microscopy techniques is in high demand to look into the origin of these discrepancies. Herein, 2D self-intercalated Cr1+nSe2 nanoflakes were synthesized as a platform to conduct the characterization. Combining scanning transmission electron microscopy (STEM) and scanning tunneling microscopy (STM), we studied in depth the microscopic structure and local electronic properties of the Cr1+nSe2 nanoflakes. The self-intercalation mechanism of ic-Cr and local stoichiometric-ratio variation in a Cr1+nSe2 ultrathin nanoflake is clearly detected at the nanometer scale. Scanning tunneling spectroscopy (STS) measurements indicate that Cr1.5Se2/Cr2Se2 and Cr1.25Se2 exhibit conductive and semiconductive behaviors, respectively. The STM tip manipulation method is further applied to manipulate the microstructure of Cr1+nSe2, which successfully produces clean zigzag-type boundaries. Our systematic microscopy study paves the way for the in-depth study of the magnetic mechanism of 2D self-intercalated magnets at the nano/micro scale and the development of new magnetic and spintronic devices.

4.
Biosensors (Basel) ; 14(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38534228

RESUMO

Development of an efficient technique for accurate and sensitive dibutyl phthalate (DBP) determination is crucial for food safety and environment protection. An ultrasensitive molecularly imprinted polymers (MIP) voltammetric sensor was herein engineered for the specific determination of DBP using poly-l-lysine/poly(3,4-ethylenedioxythiophene)/porous graphene nanocomposite (PLL/PEDOT-PG) and poly(o-phenylenediamine)-imprinted film as a label-free and sensing platform. Fabrication of PEDOT-PG nanocomposites was achieved through a simple liquid-liquid interfacial polymerization. Subsequently, poly-l-lysine (PLL) functionalization was employed to enhance the dispersibility and stability of the prepared PEDOT-PG, as well as promote its adhesion on the sensor surface. In the presence of DBP, the imprinted poly(o-phenylenediamine) film was formed on the surface of PLL/PEDOT-PG. Investigation of the physical properties and electrochemical behavior of the MIP/PLL/PEDOT-PG indicates that the incorporation of PG into PEDOT, with PLL uniformly wrapping its surface, significantly enhanced conductivity, carrier mobility, stability, and provided a larger surface area for specific recognition sites. Under optimal experimental conditions, the electrochemical response exhibited a linear relationship with a logarithm of DBP concentration within the range of 1 fM to 5 µM, with the detection limit as low as 0.88 fM. The method demonstrated exceptional stability and repeatability and has been successfully applied to quantify DBP in plastic packaging materials.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Grafite , Impressão Molecular , Nanocompostos , Fenilenodiaminas , Polímeros , Dibutilftalato , Polímeros Molecularmente Impressos , Técnicas Eletroquímicas/métodos , Grafite/química , Polilisina , Porosidade , Nanocompostos/química , Impressão Molecular/métodos , Limite de Detecção , Eletrodos
5.
Molecules ; 29(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474548

RESUMO

Transient receptor potential vanilloid 4 (TRPV4) is a widely expressed cation channel that plays an important role in many physiological and pathological processes. However, most TRPV4 drugs carry a risk of side effects. Moreover, existing screening methods are not suitable for the high-throughput screening (HTS) of drugs. In this study, a cell model and HTS method for targeting TRPV4 channel drugs were established based on a calcium-activated chloride channel protein 1 Anoctamin 1 (ANO1) and a double mutant (YFP-H148Q/I152L) of the yellow fluorescent protein (YFP). Patch-clamp experiments and fluorescence quenching kinetic experiments were used to verify that the model could sensitively detect changes in intracellular Ca2+ concentration. The functionality of the TRPV4 cell model was examined through temperature variations and different concentrations of TRPV4 modulators, and the performance of the model in HTS was also evaluated. The model was able to sensitively detect changes in the intracellular Ca2+ concentration and also excelled at screening TRPV4 drugs, and the model was more suitable for HTS. We successfully constructed a drug cell screening model targeting the TRPV4 channel, which provides a tool to study the pathophysiological functions of TRPV4 in vitro.


Assuntos
Ensaios de Triagem em Larga Escala , Canais de Cátion TRPV , Canais de Cátion TRPV/metabolismo , Anoctamina-1 , Cálcio/metabolismo
6.
Front Immunol ; 15: 1339757, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352873

RESUMO

Background: Neoadjuvant therapy for resectable gastric cancer/gastroesophageal junction tumors is progressing slowly. Although immunotherapy for advanced gastric cancer/gastroesophageal junction tumors has made great progress, the efficacy and safety of neoadjuvant immunotherapy for locally resectable gastric cancer/gastroesophageal junction tumors have not been clearly demonstrated. Here, we conducted a systematic review and meta-analysis to assess the efficacy and safety of neoadjuvant immunotherapy and advance the current research. Methods: Original articles describing the safety and efficacy of neoadjuvant immunotherapy for resectable gastric cancer/gastroesophageal junction tumors published up until October 15, 2023 were retrieved from PubMed, Embase, the Cochrane Library, and other major databases. The odds ratios (OR) and 95% confidence intervals (CIs) were calculated for heterogeneity and subgroup analysis. Results: A total of 1074 patients from 33 studies were included. The effectiveness of neoadjuvant immunotherapy was mainly evaluated using pathological complete remission (PCR), major pathological remission (MPR), and tumor regression grade (TRG). Among the included patients, 1015 underwent surgical treatment and 847 achieved R0 resection. Of the patients treated with neoadjuvant immunotherapy, 24% (95% CI: 19%-28%) achieved PCR and 49% (95% CI: 38%-61%) achieved MPR. Safety was assessed by a surgical resection rate of 0.89 (95% CI: 85%-93%), incidence of ≥ 3 treatment-related adverse events (TRAEs) of 28% (95% CI: 17%-40%), and incidence of ≥ 3 immune-related adverse events (irAEs) of 19% (95% CI: 11%-27%). Conclusion: Neoadjuvant immunotherapy, especially neoadjuvant dual-immunotherapy combinations, is effective and safe for resectable gastric/gastroesophageal junction tumors in the short term. Nevertheless, further multicenter randomized trials are required to demonstrate which combination model is more beneficial. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=358752, identifier CRD42022358752.


Assuntos
Terapia Neoadjuvante , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Quimioterapia Adjuvante , Junção Esofagogástrica/patologia , Imunoterapia/efeitos adversos , Estudos Multicêntricos como Assunto
7.
Asia Pac Psychiatry ; 16(1): e12552, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38348641

RESUMO

BACKGROUND: Major depressive disorder (MDD) is one of the global burdens of disease, and its pathogenesis remains unclear. An increasing amount of research indicates that ghrelin regulates mood in patients with MDD. Still, current results are inconsistent, and the mechanisms underlying how ghrelin modulates depressive symptoms are inconclusive, especially in first-episode drug-naïve MDD patients. Therefore, this study aims to investigate the relationship and potential mechanism between ghrelin and first-episode drug-naïve MDD. METHODS: Ninety first-episode drug-naïve MDD patients and 65 healthy controls (HCs) were included. Hamilton Depression Scale (HAMD-17) as a measure of depressive symptoms. Plasma levels of ghrelin and hypothalamic-pituitary-adrenal axis (HPA-axis) hormones were measured in all participants. RESULTS: Compared to HCs, the ghrelin levels were higher in the MDD (p < .001) and still showed significance after covarying for sex, age, and Body Mass Index (BMI). Ghrelin was positively related to corticotropin-releasing-hormone (CRH) levels (r = .867, p < .001), adrenocorticotropic hormone (ACTH) levels (r = .830, p < .001), and cortisol levels (r = .902, p < .001) in partial correlation analysis. In addition, there was a positive correlation between HAMD total score and ghrelin levels (r = .240, p = .026). Other than that, the HAMD total score also had a positive correlation with the CRH (r = .333, p = .002) and cortisol (r = .307, p = .004) levels. Further mediation analysis demonstrated that the relationship between ghrelin and HAMD total score was mediated by CRH (ab-path; ß = .4457, 95% CI = 0.0780-1.0253, c-path; ß = .2447, p = .0260, c'-path; ß = -.2009, p = .3427). CONCLUSIONS: These findings revealed that plasma ghrelin provides a pivotal link to depressive symptoms in first-episode drug-naive MDD patients. CRH mediated the relationship between ghrelin and HAMD total score. It might provide new insights into understanding the pathogenesis of MDD, contributing to intervention and treatment from this approach.


Assuntos
Transtorno Depressivo Maior , Humanos , Depressão , Sistema Hipotálamo-Hipofisário , Hidrocortisona , Grelina , Sistema Hipófise-Suprarrenal
8.
Nanomaterials (Basel) ; 14(4)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38392752

RESUMO

A tunable dual-band terahertz sensor based on graphene is proposed. The sensor consists of a metal bottom layer, a middle dielectric layer, and single-layer graphene patterned with four strips on the top. The numerical simulations results show that the proposed sensor exhibits two significant absorption peaks at 2.58 THz and 6.07 THz. The corresponding absorption rates are as high as nearly 100% and 98%, respectively. The corresponding quality factor (Q) value is 11.8 at 2.58 THz and 29.6 at 6.07 THz. By adjusting the external electric field or chemical doping of graphene, the positions of the dual-frequency resonance peak can be dynamically tuned. The excitation of plasma resonance in graphene can illustrate the mechanism of the sensor. To verify the practical application of the device, the terahertz response of different kinds and different thicknesses of the analyte is investigated and analyzed. A phenomenon of obvious frequency shifts of the two resonance peaks can be observed. Therefore, the proposed sensor has great potential applications in terahertz fields, such as material characterization, medical diagnosis, and environmental monitoring.

9.
Sci Rep ; 14(1): 4078, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374125

RESUMO

The African swine fever virus (ASFV) has caused severe economic losses in the pig industry. To monitor ASFV spread, the p30 protein has been identified as an ideal infection marker due to its early and long-term expression during the ASFV infection period. Timely monitoring of ASFV p30 enables the detection of ASFV infection and assessment of disease progression. Aptamers are an outstanding substitute for antibodies to develop an efficient tool for ASFV p30 protein detection. In this study, a series of aptamer candidates were screened by in vitro magnetic bead-based systematic evolution of ligands by exponential enrichment (MB-SELEX). An aptamer (Atc-20) finally showed high specificity and affinity (Kd = 140 ± 10 pM) against ASFV p30 protein after truncation and affinity assessment. Furthermore, an aptamer/antibody heterogeneous sandwich detection assay was designed based on Atc20, achieving a linear detection of ASFV p30 ranging from 8 to 125 ng/ml and a detection limit (LOD) of 0.61 ng/ml. This assay showed good analytical performances and effectively detected p30 protein in diluted serum samples, presenting promising potential for the development of ASFV biosensors.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Técnicas Biossensoriais , Animais , Anticorpos Antivirais , Oligonucleotídeos , Suínos , Aptâmeros de Peptídeos/química
11.
Theor Appl Genet ; 137(2): 39, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294546

RESUMO

KEY MESSAGE: Two major genetic loci, qTN5.1 and qAB9.1, were identified and finely mapped to the 255 Kb region with one potential candidate gene for tiller number and the 521 Kb region with eight candidate genes for axillary branch number, respectively. Vegetative branching including tillering and axillary branching are vital traits affecting both the plant architecture and the biomass in cereal crops. However, the mechanism underlying the formation of vegetative branching in foxtail millet is largely unknown. Here, a foxtail millet cultivar and its bushy wild relative Setaria viridis accession were used to construct segregating populations to identify candidate genes regulating tiller number and axillary branch number. Transcriptome analysis using vegetative branching bud samples of parental accessions was performed, and key differentially expressed genes and pathways regulating vegetative branching were pointed out. Bulk segregant analysis on their F2:3 segregating population was carried out, and a major QTL for tiller number (qTN5.1) and two major QTLs for axillary branch number (qAB2.1 and qAB9.1) were detected. Fine-mapping strategy was further performed on F2:4 segregate population, and Seita.5G356600 encoding ß-glucosidase 11 was identified as the promising candidate gene for qTN5.1, and eight genes, especially Seita.9G125300 and Seita.9G125400 annotated as B-S glucosidase 44, were finally identified as candidate genes for regulating axillary branching. Findings in this study will help to elucidate the genetic basis of the vegetative branching formation of foxtail millet and lay a foundation for breeding foxtail millet varieties with ideal vegetative branching numbers.


Assuntos
Setaria (Planta) , Setaria (Planta)/genética , Melhoramento Vegetal , Perfilação da Expressão Gênica , Transcriptoma , Locos de Características Quantitativas
12.
Cancer Lett ; 587: 216621, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38242198

RESUMO

Hepatocellular carcinoma (HCC) is among the deadliest malignancies worldwide and still a pressing clinical problem. Icaritin, a natural compound obtained from the Epimedium genus plant, has garnered significant attention as a potential therapeutic drug for HCC therapies. Mitophagy plays a crucial role in mitochondrial quality control through efficiently eliminating damaged mitochondria. However, the specific mechanisms of the interplay between mitophagy and apoptosis in HCC is still unclear. We aimed to explore the cross-talk between icaritin-induced mitophagy and apoptosis in HCC cells and investigate its potential mechanisms. Firstly, we confirmed that icaritin inhibits proliferation and migration while inducing mitochondrial damage and reactive oxygen species (ROS) production in HCC cells. Secondly, based on proteomics analysis, we discovered that icaritin inhibits the growth of tumor cells and disrupts their mitochondrial homeostasis through the regulation of both mitophagy and apoptosis. Thirdly, icaritin causes mitophagy mediated by PINK1-Parkin signaling via regulating feedforward loop. Furthermore, knockdown of PINK1/Parkin leads to inhibition of mitophagy, which promotes cell death induced by icaritin in HCC cells. Finally, autophagy/mitophagy inhibitors remarkably enhance icaritin-induced cell death and anticancer efficacy. Collectively, our findings reveal that icaritin suppresses growth, proliferation and migration of HCC cell through induction of mitophagy and apoptosis, while inhibition of mitophagy significantly increased the anti-cancer and pro-apoptotic effects of icaritin, indicating that targeting autophagy or mitophagy is a novel approach to overcome drug resistance and enhance anticancer therapies.


Assuntos
Carcinoma Hepatocelular , Flavonoides , Neoplasias Hepáticas , Humanos , Mitofagia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/patologia , Autofagia , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo
13.
Plant Physiol Biochem ; 207: 108342, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219427

RESUMO

Respiratory burst oxidase homolog (Rboh) family genes play crucial functions in development and growth. However, comprehensive and systematic investigation of Rboh family members in Rosaceae and their specific functions during pear pollen development are still limited. In the study, 63 Rboh genes were identified from eight Rosaceae genomes (Malus domestica, Pyrus bretschneideri, Pyrus communis, Prunus persica, Rubus occidentalis, Fragaria vesca, Prunus mume and Prunus avium) and divided into seven main subfamilies (I-VII) according to phylogenetic and structural features. Different modes of gene duplication led to the expansion of Rboh family, with purifying selection playing a vital role in the evolution of Rboh genes. In addition, RNA sequencing and qRT-PCR results indicated that PbRbohH and PbRbohJ were specifically high-expressed in pear pollen. Subsequently, subcellular localization revealed that PbRbohH/J distributed at the plasma membrane. Furthermore, by pharmacological analysis and antisense oligodeoxynucleotide assay, PbRbohH/J were demonstrated to mediate the formation of reactive oxygen species (ROS) to manage pollen tube growth. In conclusion, our results provide useful insights into the functions, expression patterns, evolutionary history of the Rboh genes in pear and other Rosaceae species.


Assuntos
Pyrus , Rosaceae , Pyrus/genética , Pyrus/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tubo Polínico/genética , Filogenia , Genoma de Planta , Rosaceae/genética
14.
Clin Endocrinol (Oxf) ; 100(3): 294-303, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38214116

RESUMO

This study aimed to evaluate whether there is a causal relationship between autoimmune thyroid disorders (AITDs) and telomere length (TL) in the European population and whether there is reverse causality. In this study, Mendelian randomization (MR) and colocalization analysis were conducted to assess the potential causal relationship between AITDs and TL using summary statistics from large-scale genome-wide association studies, followed by analysis of the relationship between TL and thyroid stimulating hormone and free thyroxine (FT4) to help interpret the findings. The inverse variance weighted (IVW) method was used to estimate the causal estimates. The weighted median, MR-Egger and leave-one-out methods were used as sensitivity analyses. The IVW method results showed a significant causal relationship between autoimmune hyperthyroidism and TL (ß = -1.93 × 10-2 ; p = 4.54 × 10-5 ). There was no causal relationship between autoimmune hypothyroidism and TL (ß = -3.99 × 10-3 ; p = 0.324). The results of the reverse MR analysis showed that genetically TL had a significant causal relationship on autoimmune hyperthyroidism (IVW: odds ratio (OR) = 0.49; p = 2.83 × 10-4 ) and autoimmune hypothyroidism (IVW: OR = 0.86; p = 7.46 × 10-3 ). Both horizontal pleiotropy and heterogeneity tests indicated the validity of our bidirectional MR study. Finally, colocalization analysis suggested that there were shared causal variants between autoimmune hyperthyroidism and TL, further highlighting the robustness of the results. In conclusion, autoimmune hyperthyroidism may accelerate telomere attrition, and telomere attrition is a causal factor for AITDs.


Assuntos
Doença de Graves , Doença de Hashimoto , Hipotireoidismo , Tireoidite Autoimune , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Telômero/genética , Hipotireoidismo/genética
15.
Biomed Chromatogr ; 38(2): e5782, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38016814

RESUMO

Natural medicines play a crucial role in clinical drug applications, serving as a primary traditional Chinese medicine for the clinical treatment of liver fibrosis. Understanding the in vivo metabolic process of the Fuzheng Huayu (FZHY) formula is essential for delving into its material basis and mechanism. In recent years, there has been a growing body of research focused on the mechanisms and component analysis of FZHY. This study aimed to examine the pharmacokinetics of FZHY in healthy volunteers following oral administration. Blood samples were collected at designated time intervals after the oral intake of 9.6-g FZHY tablets. A UHPLC-Q/Exactive method was developed to assess the plasma concentrations of five components post-FZHY ingestion. The peak time for all components occurred within 10 min. The peak concentration (Cmax ) values for amygdalin, schisandrin, and schisandrin A ranged from 3.47 to 28.80 ng/mL, with corresponding AUC(0-t) values ranging from 10.63 to 103.20 ng h/mL. For schisandrin B and prunasin, Cmax values were in the range of 86.52 to 229.10 ng/mL, and their AUC(0-t) values ranged from 375.26 to 1875.54 ng h/mL, indicating significant exposure within the body. These findings demonstrate that the developed method enables rapid and accurate detection and quantification of the five components in FZHY, offering a valuable reference for its clinical study.


Assuntos
Medicamentos de Ervas Chinesas , Humanos , Medicamentos de Ervas Chinesas/farmacocinética , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Medicina Tradicional Chinesa/métodos , Administração Oral , Comprimidos
16.
Sci Total Environ ; 914: 169693, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38160845

RESUMO

San Antonio has been designated as ozone nonattainment under the current National Ambient Air Quality Standards (NAAQS). Ozone events in the city typically occur in two peaks, characterized by a pronounced spring peak followed by a late summer peak. Despite higher ozone levels, the spring peak has received less attention than the summer peak. To address this research gap, we used the Weather Research and Forecasting (WRF)-driven GEOS-Chem (WRF-GC) model to simulate San Antonio's ozone changes in the spring month of May from 2017 to 2021 and quantified the respective contributions from changes in anthropogenic emissions and meteorology. In addition to modeling, observations from the San Antonio Field Studies (SAFS), the Texas Commission on Environmental Quality (TCEQ) Continuous Ambient Monitoring Stations (CAMS), and the spaceborne TROPOspheric Monitoring Instrument (TROPOMI) are used to examine and validate changes in ozone and precursors. Results show that the simulated daytime mean surface ozone in May 2021 is 3.8 ± 0.6 ppbv lower than in May 2017, which is slightly less than the observed average differences of -5.3 ppbv at CAMS sites. The model predicted that the anthropogenic emission-induced changes contribute to a 1.4 ± 0.5 ppbv reduction in daytime ozone levels, while the meteorology-induced changes account for a 2.4 ± 0.6 ppbv reduction over 2017-2021. This suggests that meteorology plays a relatively more important role than anthropogenic emissions in explaining the spring ozone differences between the two years. We additionally identified (1) reduced NO2 and HCHO concentrations as chemical reasons, and (2) lower temperature, higher humidity, increased wind speed, and a stronger Bermuda High as meteorological reasons for lower ozone levels in 2021 compared to 2017. The quantification of the different roles of meteorology and ozone precursor concentrations helps understand the cause and variation of ozone changes in San Antonio over recent years.

18.
Fluids Barriers CNS ; 20(1): 88, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38053174

RESUMO

Current strategies to identify ligands for brain delivery select candidates based on preferential binding to cell-membrane components (CMC) on brain endothelial cells (EC). However, such strategies generate ligands with inherent brain specificity limitations, as the CMC (e.g., the transferrin receptor TfR1) are also significantly expressed on peripheral EC. Therefore, novel strategies are required to identify molecules allowing increased specificity of therapy brain delivery. Here, we demonstrate that, while individual CMC are shared between brain EC and peripheral EC, their endocytic internalization rate is markedly different. Such differential endocytic rate may be harnessed to identify molecular tags for brain targeting based on their selective retention on the surface of brain EC, thereby generating 'artificial' targets specifically on the brain vasculature. By quantifying the retention of labelled proteins on the cell membrane, we measured the general endocytic rate of primary brain EC to be less than half that of primary peripheral (liver and lung) EC. In addition, through bio-panning of phage-displayed peptide libraries, we unbiasedly probed the endocytic rate of individual CMC of liver, lung and brain endothelial cells. We identified phage-displayed peptides which bind to CMC common to all three endothelia phenotypes, but which are preferentially endocytosed into peripheral EC, resulting in selective retention on the surface of brain EC. Furthermore, we demonstrate that the synthesized free-form peptides are capable of generating artificial cell-surface targets for the intracellular delivery of model proteins into brain EC with increasing specificity over time. The developed identification paradigm, therefore, demonstrates that the lower endocytic rate of individual CMC on brain EC can be harnessed to identify peptides capable of generating 'artificial' targets for the selective delivery of proteins into the brain vasculature. In addition, our approach identifies brain-targeting peptides which would have been overlooked by conventional identification strategies, thereby increasing the repertoire of candidates to achieve specific therapy brain delivery.


Assuntos
Encéfalo , Células Endoteliais , Células Endoteliais/metabolismo , Endotélio/metabolismo , Encéfalo/metabolismo , Peptídeos/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-38038762

RESUMO

Childhood maltreatment (CM) has been linked to social cognition deficits in major depressive disorder (MDD), but little is known about sex-specific effects. This study aimed to investigate the sex-specific associations of CM with social cognition in first-episode drug-naive patients with MDD. A total of 117 first-episode drug-naive patients with MDD and 134 healthy controls (HCs) were recruited and assessed for demographic and clinical characteristics. All participants completed the Childhood Trauma Questionnaire (CTQ), Toronto Alexithymia Scale (TAS-20), Interpersonal Reactivity Index-C (IRI), and Facial Emotion Recognition Test. Partial correlation analysis was used to explore the sex-specific association of CM with social cognition. Our findings revealed significant differences in the associations of CM with social cognition between males and females in MDD patients. In comparison to HCs, the associations of CM with social cognition displayed distinct and even contrasting sex-specific patterns in MDD patients. Specifically, male MDD patients exhibited unique imbalanced associations between emotional neglect and alexithymia, while both female and male MDD patients shared imbalanced associations of childhood abuse with empathy. These results emphasize the importance of considering the sex-specific associations of CM with social cognition in MDD and highlight the need for personalized interventions and treatments based on sex for MDD patients with a history of CM.

20.
Cancer ; 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38079306

RESUMO

BACKGROUND: Immune-checkpoint blockade (ICB) therapy shows promise for treating aggressive triple-negative breast cancer (TNBC). However, only some patients benefit from ICB, revealing an urgent need for identifying novel strategies for sensitizing patients to ICB. Previously, the authors demonstrated that type-I protein arginine methyltransferases (PRMTs) regulated antiviral innate-immune responses in TNBC by altering RNA splicing. This study aimed to explore the effects of targeting type-I PRMTs on the tumor microenvironment (TME) and the efficacy of ICB therapy against TNBC. METHODS: Single-cell transcriptomic analysis was performed to investigate the effects of type-I PRMT inhibition on the TME, especially T-cell subsets. Single-cell T-cell receptor sequencing was performed to analyze the diversity and dynamics of the T-cell repertoire. A syngeneic murine model of TNBC was used to evaluate the therapeutic efficacy and immune memory effect of combining a type-I PRMT inhibitor (MS023) with an anti-programmed cell death protein 1 (PD-1) antibody. RESULTS: Type-I PRMT inhibition combined with anti-PD-1 therapy reduced tumor growth. Mechanistically, type-I PRMT inhibition reshaped the TME. Increased CD8 T-cell infiltration was verified using flow cytometry. Increased clonotypes and clonal diversity were also observed after MS023 treatment, which contributed to immune memory following combination treatment. CONCLUSIONS: Targeting type-I PRMT can potentially improve immunotherapeutic efficacies in patients with TNBC. By enhancing the tumor immunogenicity and promoting a more favorable immune microenvironment, this combined approach may enable more patients with TNBC to benefit from immunotherapies.

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