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We investigated the influence of the medium on the perception of depicted objects and materials. Oil paintings and their reproductions in engravings were chosen because they are vastly distinctive media while having completely identical content. A total of 15 pairs were collected, consisting of 88 fragments depicting different materials, including fabric, skin, wood and metal. Besides the original condition, we created three manipulations to understand the effect of colour (a greyscale version) and contrast (equalised histograms towards both painting and engraving). We performed rating experiments on five attributes: three-dimensionality, glossiness, convincingness, smoothness and softness. An average of 25 participants finished each of the 20 online experimental sessions (five attributes X four conditions). Besides clear correlations between the two media, the differences mainly show in their means (different levels of perceived attributes) and standard deviations (perceived range). In most sessions, paintings depict a wider range than engravings. In addition, it was the histogram equalisation (global contrast) that made the most impact on perceived attributes, rather than colour removal. This suggests that engravers compensated for the lack of colour by exploiting the possibilities of local contrast.
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Immune checkpoint blocking (ICB), a tumor treatment based on the mechanism of T-cell activation, has shown high efficacy in clinical trials, but not all patients benefit from it. Immune checkpoint inhibitors (ICIs) do not respond to cold tumors that lack effective T-cell infiltration but respond well to hot tumors with sufficient T-cell infiltration. How to convert an unresponsive cold tumor into a responsive hot tumor is an important topic in cancer immunotherapy. Ferroptosis, a newly discovered immunogenic cell death (ICD) form, has great potential in cancer therapy. In the process of deeply understanding the mechanism of cold tumor formation, it was found that ferroptosis showed a powerful immune-activating effect by improving T-cell infiltration, and the combination of ICB therapy significantly enhanced the anti-tumor efficacy. This paper reviews the complex relationship between T cells and ferroptosis, as well as summarizes the various mechanisms by which ferroptosis enhances T cell infiltration: reactivation of T cells and reversal of immunosuppressive tumor microenvironment (TME), as well as recent advances of ICI in combination with targeted ferroptosis therapies, which provides guidance for better improving the ICB efficacy of cold tumors.
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BACKGROUND: Maintenance therapy could significantly improve the prognosis of patients with advanced non-small cell lung cancer (NSCLC) receiving chemotherapy. Anlotinib is effective, tolerable, and convenient in administration as a third-line treatment for NSCLC. This study aimed to evaluate the efficacy and safety of maintenance therapy with anlotinib after platinum-based induction chemotherapy for patients with advanced NSCLC. METHODS: This pooled analysis of 2 multicenter, open-label, single-arm, phase 2 clinical trials (ALTER-L014 and ALTER-L011) enrolled patients with locally advanced or metastatic NSCLC and without known sensitive mutations in China between September 2018 and January 2021. The primary outcome was progression-free survival. The secondary outcomes were objective response rate, disease control rate, overall survival, and safety. RESULTS: The data of 23 patients were pooled, with 15 from ALTER-L014 and 8 from ALTER-L011. At the cutoff date of June 13, 2021, the median progression-free survival since the start of maintenance therapy was 5.95 (95% confidence interval, 4.30-8.80) months. Nineteen patients had stable disease, 1 had a partial response and 3 had progressive disease. The objective response rate was 4.35%, while disease control rate was 86.96%. The median overall survival of the patients since the start of maintenance therapy was 18.60 (95% confidence interval, 6.87-22.80) months. The incidence of adverse events of gradeâ ≥â 3 was 21.7%. CONCLUSION: Anlotinib might offer a new option for maintenance treatment in patients with locally advanced or metastatic NSCLC without known sensitive mutations after standard first-line platinum-based chemotherapy.
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Carcinoma de Pulmón de Células no Pequeñas , Indoles , Quimioterapia de Inducción , Neoplasias Pulmonares , Quinolinas , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Indoles/uso terapéutico , Indoles/administración & dosificación , Indoles/efectos adversos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Femenino , Quinolinas/uso terapéutico , Quinolinas/administración & dosificación , Quinolinas/efectos adversos , Anciano , Quimioterapia de Inducción/métodos , Quimioterapia de Mantención/métodos , Adulto , Supervivencia sin Progresión , Antineoplásicos/uso terapéutico , Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéuticoRESUMEN
High-strength low-alloy steels are widely used, but their traditional heat-treatment process is complex, energy-intensive, and makes it difficult to fully exploit the material's potential. In this paper, the electropulsing processing technology was applied to the quenching and tempering process of ZG25SiMn2CrB steel. Through microstructural characterization and mechanical property testing, the influence of electropulsing on the solid-state phase transition process of annealing steel was systematically studied. The heating process of the specimen with the annealing state (initial state) is the diffusion-type transition. As the discharge time increased, the microstructure gradually transformed from ferrite/pearlitic to slate martensite. Optimal mechanical properties and fine microstructure were achieved after quenching at 500 ms. The steel subjected to rapid tempering with 160 ms electropulsing exhibited good, comprehensive mechanical properties (tensile strength 1609 MPa, yield strength 1401.27 MPa, elongation 11.63%, and hardness 48.68 HRC). These favorable mechanical properties are attributed to the coupled impact of thermal and non-thermal effects induced by high-density pulse current. Specifically, the thermal effect provides the thermodynamic conditions for phase transformation, while the non-thermal effect reduces the nucleation barrier of austenite, which increases the nucleation rate during instantaneous heating, and the following rapid cooling suppresses the growth of austenite grains. Additionally, the fine microstructure prevents the occurrence of temper brittleness.
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Neurons on the left and right sides of the nervous system often show asymmetric properties, but how such differences arise is poorly understood. Genetic screening in zebrafish revealed that loss of function of the transmembrane protein Cachd1 resulted in right-sided habenula neurons adopting left-sided identity. Cachd1 is expressed in neuronal progenitors, functions downstream of asymmetric environmental signals, and influences timing of the normally asymmetric patterns of neurogenesis. Biochemical and structural analyses demonstrated that Cachd1 can bind simultaneously to Lrp6 and Frizzled family Wnt co-receptors. Consistent with this, lrp6 mutant zebrafish lose asymmetry in the habenulae, and epistasis experiments support a role for Cachd1 in modulating Wnt pathway activity in the brain. These studies identify Cachd1 as a conserved Wnt receptor-interacting protein that regulates lateralized neuronal identity in the zebrafish brain.
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Canales de Calcio , Habénula , Neurogénesis , Neuronas , Vía de Señalización Wnt , Proteínas de Pez Cebra , Pez Cebra , Animales , Receptores Frizzled/metabolismo , Receptores Frizzled/genética , Habénula/metabolismo , Habénula/embriología , Mutación con Pérdida de Función , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Neuronas/metabolismo , Receptores Wnt/metabolismo , Receptores Wnt/genética , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Canales de Calcio/genética , Canales de Calcio/metabolismoRESUMEN
Ferroptosis is an unconventional programmed cell death mode caused by phospholipid peroxidation dependent on iron. Emerging immunotherapies (especially immune checkpoint inhibitors) have the potential to enhance lung cancer patients' long-term survival. Although immunotherapy has yielded significant positive applications in some patients, there are still many mechanisms that can cause lung cancer cells to evade immunity, thus leading to the failure of targeted therapies. Immune-tolerant cancer cells are insensitive to conventional death pathways such as apoptosis and necrosis, whereas mesenchymal and metastasis-prone cancer cells are particularly vulnerable to ferroptosis, which plays a vital role in mediating immune tolerance resistance by tumors and immune cells. As a result, triggering lung cancer cell ferroptosis holds significant therapeutic potential for drug-resistant malignancies. Here, we summarize the mechanisms underlying the suppression of ferroptosis in lung cancer, highlight its function in the lung cancer immune microenvironment, and propose possible therapeutic strategies.
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Ferroptosis , Inmunoterapia , Neoplasias Pulmonares , Microambiente Tumoral , Ferroptosis/efectos de los fármacos , Ferroptosis/inmunología , Humanos , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Inmunoterapia/métodos , Microambiente Tumoral/inmunología , Microambiente Tumoral/efectos de los fármacos , AnimalesRESUMEN
BACKGROUND: The development of immune checkpoint inhibitors has made a significant breakthrough in the treatment of non-small-cell lung cancer (NSCLC). However, there remains a huge unmet clinical need for patients with acquired resistance after initial treatment response. METHODS: This study evaluated the combination of IBI310 (an anti-cytotoxic T lymphocyte-associated antigen-4 [CTLA-4] antibody) and sintilimab (an anti-programmed death 1 [PD-1]) antibody) in NSCLC patients who have previously been treated with anti-PD-1/ligand (L)1 and acquired resistance. The patients were randomly assigned to receive either a lower dose of IBI310 (1 mg/kg Q3W, cohort A) or a higher dose of IBI310 (3 mg/kg Q3W, cohort B) in combination with sintilimab (200 mg Q3W). The primary endpoints of the study were objective response rate (ORR) assessed by RECISTv1.1 and safety, while secondary endpoints included disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). RESULTS: As of November 2, 2023, the study had enrolled 30 patients, with 15 patients in each cohort. The ORR was 13.3% (2/15, 95% confidence interval [CI], 1.7-40.5) in cohort B. DCR were 46.7% (95% CI, 21.3-73.4) and 66.7% (95% CI, 38.4-88.2) in cohorts A and B, respectively. In cohorts A and B of this trial, the median follow-up times were 4.2 and 5.6 months, respectively. Median PFS was 1.45 (95% CI, 1.35-2.73) versus 2.73 (95% CI, 1.41-4.90) months for cohort A versus B; the median OS was 7.03 (95% CI, 3.09-not calculable [NC]) months in cohort A and 8.90 (95% CI, 5.13-NC) months in cohort B. Of the 30 patients, 86.7% in both cohorts experienced treatment-related adverse events (TRAEs) with Grade ≥3 TRAEs occurring in 40% and 53.3% of patients in cohorts A and B, respectively. CONCLUSION: IBI310 3 mg/kg Q3W plus sintilimab was effective in a small number of previously treated anti-PD-1/L1-resistant NSCLC patients.
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Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Anticuerpos Monoclonales , Anticuerpos Monoclonales Humanizados/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológicoRESUMEN
Cancer stem cells (CSCs), a small population of stem cells existing in cancer cells, are considered as the "culprits" of tumor recurrence, metastasis, and drug resistance. Ferroptosis is a promising new lead in anti-cancer therapy. Because of unique metabolic characteristics, CSCs' growth is more dependent on the iron and lipid than ordinary cancer cells. When the metabolism of iron/lipid is disordered, that is, imbalanced redox homeostasis, CSCs are more susceptible to ferroptosis. The expression of Nuclear factor E2-related factor 2 (Nrf2), a molecule playing a major regulatory role in redox homeostasis, determines whether the cells are under oxidative stress and ferroptosis occurs. Nrf2 expression level is higher in CSCs, indicating stronger dependence on Nrf2. Here we expound the unique biological and metabolic characteristics of CSCs, explore the mechanism of inducing ferroptosis by targeting Nrf2, thus providing promising new targets for eliminating aggressive tumors and achieving the goal of curing tumors.
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Ferroptosis , Neoplasias , Humanos , Factor 2 Relacionado con NF-E2 , Células Madre Neoplásicas , Hierro , LípidosRESUMEN
In recent years, the indications for immunotherapy in cancer treatment have been expanding. The increased risk of cancer in young people, coupled with the fact that many women or men choose to delay childbearing, has made an increasing number of patients of childbearing age eligible for immunotherapy. Furthermore, with the improvements of various treatments, more young people and children are able to survive cancer. As a result, long-term sequelae of cancer treatments, such as reproductive dysfunction, are increasingly important for survivors. While many anti-cancer drugs are known to cause reproduction dysfunction, the effects of immune checkpoint inhibitors (ICIs) on reproduction function remain largely unknown. Through a retrospective analysis of previous reports and literature, this article aims to elucidate the causes of reproductive dysfunction induced by ICIs and focus on their specific mechanisms, in order to providing some guidance to clinicians and patients.
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Antineoplásicos , Neoplasias , Masculino , Niño , Humanos , Femenino , Adolescente , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Estudios Retrospectivos , Antineoplásicos/uso terapéutico , Inmunoterapia/efectos adversosRESUMEN
Most studies on the perception of style have used whole scenes/entire paintings; in our study, we isolated a single motif (an apple) to reduce or even eliminate the influence of composition, iconography, and other contextual information. In this article, we empirically address two fundamental questions of the existence (Experiment 1) and description (Experiment 2) of style. We chose 48 cut-outs of mostly Western European paintings (15th to 21st century) that showed apples. In Experiment 1, 415 unique participants completed online triplet similarity tasks. Multidimensional scaling (MDS) reached a nonrandom three-dimensional (3D) embedding, showing that participants are able to judge stylistic differences in a systematic way. We also found a strong correlation between creation year and embedding, both a linear correlation with Dimension 2, and a rotational correlation in the first two dimensions. To interpret the embedding further, in Experiment 2, we fitted three color statistics and nine attribute ratings (glossiness, three-dimensionality, convincingness, brush coarseness, etc.) to the 3D perceptual style space. Results showed that Dimension 1 is associated with spatial attributes (Smoothness, Brushstroke coarseness) and Convincingness, Dimension 2 is related to Hue, and Dimension 3 is related to Chroma. The results suggest that texture and color are two important variables for style perception. By isolating the motifs, we could exclude higher levels of information such as composition and context. Interestingly, the results reinforce previous findings using whole scenes, suggesting that style can already be perceived in sometimes very small fragments of paintings.
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Pinturas , Humanos , PercepciónRESUMEN
N-Acyl indolines 4 are potent, non-covalent Notum inhibitors developed from a covalent virtual screening hit 2a. The lead compounds were simple to synthesise, achieved excellent potency in a biochemical Notum-OPTS assay and restored Wnt signalling in a cell-based TCF/LEF reporter assay. Multiple high resolution X-ray structures established a common binding mode of these inhibitors with the indoline bound centred in the palmiteolate pocket with key interactions being aromatic stacking and a water mediated hydrogen bond to the oxyanion hole. These N-acyl indolines 4 will be useful tools for use in vitro studies to investigate the role of Notum in disease models, especially when paired with a structurally related covalent inhibitor (e.g. 4w and 2a). Overall, this study highlights the designed switch from covalent to non-covalent Notum inhibitors and so illustrates a complementary approach for hit generation and target inhibition.
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Hidrolasas de Éster Carboxílico , Vía de Señalización Wnt , Fenómenos BiofísicosRESUMEN
This pilot study (NCT03958097; https://www.clinicaltrials.gov/ct2/show/NCT03958097) was aimed to evaluate the efficacy and safety of PD-1 antibody combined autologous NK cells in the treatment of patients with stage IIIB/IIIC or IV non-small-cell lung cancer (NSCLC) who failed the first-line platinum-based chemotherapy. All patients received both sintilimab 200mg and 3×109 NK cells every 3 weeks. 20 patients were enrolled, median follow up time was 22.6 months. The median PFS was 11.6 months, ORR was 45%. Median OS was 17.7 months, 6-month OS rate and 12-month OS rate was 95.0% and 80.0%. Unexpected adverse events were not observed. 2 patients reported grade 3 adverse events (hypertriglyceridemia, neutropenia and increased creatine kinase). The autologous NK cells did not add extra adverse events to the ICI treatment. Autologous NK plus sintilimab showed promising antitumor activity and an acceptable safety profile in advanced driven-mutation negative NSCLC who failed on the first line treatment.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Células Asesinas Naturales/patología , Neoplasias Pulmonares/tratamiento farmacológico , Proyectos Piloto , Platino (Metal)/uso terapéuticoRESUMEN
Colorectal cancer (CRC) has been one of the most common cancers and maintains the second-highest incidence and mortality rates among all cancers. The high risk of recurrence and metastasis and poor survival are still huge challenges in CRC therapy, in which the discovery of ferroptosis provides a novel perspective. It has been ten years since a unique type of regulated cell death driven by iron accumulation and lipid peroxidation was proposed and named ferroptosis. During the past decade, there have been multiple pieces of evidence suggesting that ferroptosis participates in the pathophysiological processes during disease progression. In this review, we describe ferroptosis as an imbalance of oxidant systems and anti-oxidants which results in lipid peroxidation, membrane damage, and finally cell death. We elaborate on the mechanisms of ferroptosis and systematically summarize recent studies on the regulatory pathways of ferroptosis in CRC from various perspectives, ranging from encoding genes, noncoding RNAs to regulatory proteins. Finally, we discuss the potential therapeutic role of ferroptosis in CRC treatments.
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Echoviruses, for which there are currently no approved vaccines or drugs, are responsible for a range of human diseases, for example echovirus 11 (E11) is a major cause of serious neonatal morbidity and mortality. Decay-accelerating factor (DAF, also known as CD55) is an attachment receptor for E11. Here, we report the structure of the complex of E11 and the full-length ectodomain of DAF (short consensus repeats, SCRs, 1-4) at 3.1 Å determined by cryo-electron microscopy (cryo-EM). SCRs 3 and 4 of DAF interact with E11 at the southern rim of the canyon via the VP2 EF and VP3 BC loops. We also observe an unexpected interaction between the N-linked glycan (residue 95 of DAF) and the VP2 BC loop of E11. DAF is a receptor for at least 20 enteroviruses and we classify its binding patterns from reported DAF/virus complexes into two distinct positions and orientations, named as E6 and E11 poses. Whilst 60 DAF molecules can attach to the virion in the E6 pose, no more than 30 can attach to E11 due to steric restrictions. Analysis of the distinct modes of interaction and structure and sequence-based phylogenies suggests that the two modes evolved independently, with the E6 mode likely found earlier.
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Infecciones por Enterovirus , Enterovirus , Recién Nacido , Humanos , Microscopía por Crioelectrón , Antígenos CD55 , Enterovirus/metabolismo , Enterovirus Humano B/metabolismoRESUMEN
BACKGROUND: To identify regulatory ncRNA molecules that can cause differential expression of CDH2 in intervertebral disc degeneration (IDD) and explore whether there are other ways to affect the progression of IDD. METHODS: A primary culture of human nucleus pulposus (NP) cells was established and identified by immunofluorescence. An in vitro IDD model was constructed by compressing human NP cells, and the MTT assay was used to measure cell viability. Changes in the ncRNA group were analysed by RNA-seq. The expression levels of hsa_circ_7042, CDH2, and miR-369-3p were detected by qPCR. Cell apoptosis, senescence, and extracellular matrix (ECM) metabolism were detected by flow cytometry, ß-galactosidase staining, and Western blotting. hsa_circ_7042, miR-369-3p, and bone morphogenetic protein 2 (BMP2) were verified by luciferase and RNA immunoprecipitation (RIP) analyses. The PI3K/Akt pathway was validated by transfection of BMP2 siRNA. Furthermore, a mouse model of lumbar spine instability was constructed. circ_7042 adenovirus was packaged and injected into the intervertebral discs of mice, and the influence of circ_7042 overexpression on intervertebral disc degeneration was determined. RESULTS: Western blotting, qPCR, and flow cytometry analyses confirmed that overexpression of circ_7042 could downregulate miR-369-3p and upregulate the expression of CDH2 and BMP2 in IDD cell and animal models. Additionally, the levels of apoptotic and senescent cells decreased, and ECM degradation decreased. The PI3K/Akt pathway was significantly activated after circ_7042 was overexpressed. The injection of circ_7042-overexpressing adenovirus effectively reduced ECM degradation and the level of apoptosis in NP tissue. CONCLUSIONS: circ_7042 could upregulate the expression of CDH2 and BMP2 by absorbing miR-369-3p, and the increased BMP2 activated the PI3K/Akt pathway, thus improving IDD.
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Degeneración del Disco Intervertebral , MicroARNs , Animales , Apoptosis/genética , Proteína Morfogenética Ósea 2 , Humanos , Degeneración del Disco Intervertebral/genética , Degeneración del Disco Intervertebral/metabolismo , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
Sizzled (Szl) is both a secreted frizzled related protein (sFRP) and a naturally occurring inhibitor of the zinc metalloproteinase bone morphogenetic protein-1 (BMP-1), a key regulator of extracellular matrix assembly and growth factor activation. Here we present a new crystal structure for Szl which differs from that previously reported by a large scale (90°) hinge rotation between its cysteine-rich and netrin-like domains. We also present results of a molecular docking analysis showing interactions likely to be involved in the inhibition of BMP-1 activity by Szl. When compared with known structures of BMP-1 in complex with small molecule inhibitors, this reveals features that may be helpful in the design of new inhibitors to prevent the excessive accumulation of extracellular matrix that is the hallmark of fibrotic diseases.
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Péptidos y Proteínas de Señalización Intercelular , Proteínas de Xenopus , Proteína Morfogenética Ósea 1/metabolismo , Proteína Morfogenética Ósea 2/metabolismo , Proteína Morfogenética Ósea 7/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Simulación del Acoplamiento Molecular , Unión Proteica , Proteínas de Xenopus/metabolismoRESUMEN
Signaling by the human C-type lectin-like receptor, natural killer (NK) cell inhibitory receptor NKR-P1, has a critical role in many immune-related diseases and cancer. C-type lectin-like receptors have weak affinities to their ligands; therefore, setting up a comprehensive model of NKR-P1-LLT1 interactions that considers the natural state of the receptor on the cell surface is necessary to understand its functions. Here we report the crystal structures of the NKR-P1 and NKR-P1:LLT1 complexes, which provides evidence that NKR-P1 forms homodimers in an unexpected arrangement to enable LLT1 binding in two modes, bridging two LLT1 molecules. These interaction clusters are suggestive of an inhibitory immune synapse. By observing the formation of these clusters in solution using SEC-SAXS analysis, by dSTORM super-resolution microscopy on the cell surface, and by following their role in receptor signaling with freshly isolated NK cells, we show that only the ligation of both LLT1 binding interfaces leads to effective NKR-P1 inhibitory signaling. In summary, our findings collectively support a model of NKR-P1:LLT1 clustering, which allows the interacting proteins to overcome weak ligand-receptor affinity and to trigger signal transduction upon cellular contact in the immune synapse.
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Células Asesinas Naturales , Receptores de Superficie Celular , Antígenos de Superficie , Análisis por Conglomerados , Humanos , Lectinas Tipo C , Ligandos , Subfamilia B de Receptores Similares a Lectina de Células NK , Dispersión del Ángulo Pequeño , Sinapsis , Difracción de Rayos XRESUMEN
The Wnt signaling suppressor Notum is a promising target for osteoporosis, Alzheimer's disease, and colorectal cancers. To develop novel Notum inhibitors, we used an X-ray crystallographic fragment screen with the Diamond-SGC Poised Library (DSPL) and identified 59 fragment hits from the analysis of 768 data sets. Fifty-eight of the hits were found bound at the enzyme catalytic pocket with potencies ranging from 0.5 to >1000 µM. Analysis of the fragments' diverse binding modes, enzymatic inhibitory activities, and chemical properties led to the selection of six hits for optimization, and five of these resulted in improved Notum inhibitory potencies. One hit, 1-phenyl-1,2,3-triazole 7, and its related cluster members, have shown promising lead-like properties. These became the focus of our fragment development activities, resulting in compound 7d with IC50 0.0067 µM. The large number of Notum fragment structures and their initial optimization provided an important basis for further Notum inhibitor development.
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Cristalografía por Rayos XRESUMEN
Notum is a carboxylesterase that suppresses Wnt signaling through deacylation of an essential palmitoleate group on Wnt proteins. There is a growing understanding of the role Notum plays in human diseases such as colorectal cancer and Alzheimer's disease, supporting the need to discover improved inhibitors, especially for use in models of neurodegeneration. Here, we have described the discovery and profile of 8l (ARUK3001185) as a potent, selective, and brain-penetrant inhibitor of Notum activity suitable for oral dosing in rodent models of disease. Crystallographic fragment screening of the Diamond-SGC Poised Library for binding to Notum, supported by a biochemical enzyme assay to rank inhibition activity, identified 6a and 6b as a pair of outstanding hits. Fragment development of 6 delivered 8l that restored Wnt signaling in the presence of Notum in a cell-based reporter assay. Assessment in pharmacology screens showed 8l to be selective against serine hydrolases, kinases, and drug targets.
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Inhibidores Enzimáticos , Esterasas , Encéfalo/metabolismo , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Esterasas/metabolismo , Vía de Señalización WntRESUMEN
Neural-vascular coupling (NVC) is the process by which oxygen and nutrients are delivered to metabolically active neurons by blood vessels. Murine models of NVC disruption have revealed its critical role in healthy neural function. We hypothesized that, in humans, aging exerts detrimental effects upon the integrity of the neural-glial-vascular system that underlies NVC. To test this hypothesis, calibrated functional magnetic resonance imaging (cfMRI) was used to characterize age-related changes in cerebral blood flow (CBF) and oxygen metabolism during visual cortex stimulation. Thirty-three younger and 27 older participants underwent cfMRI scanning during both an attention-controlled visual stimulation task and a hypercapnia paradigm used to calibrate the blood-oxygen-level-dependent signal. Measurement of stimulus-evoked blood flow and oxygen metabolism permitted calculation of the NVC ratio to assess the integrity of neural-vascular communication. Consistent with our hypothesis, we observed monotonic NVC ratio increases with increasing visual stimulation frequency in younger adults but not in older adults. Age-related changes in stimulus-evoked cerebrovascular and neurometabolic signal could not fully explain this disruption; increases in stimulus-evoked neurometabolic activity elicited corresponding increases in stimulus-evoked CBF in younger but not in older adults. These results implicate age-related, demand-dependent failures of the neural-glial-vascular structures that comprise the NVC system.