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1.
Nature ; 622(7984): 754-760, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37730999

RESUMO

Single-atom catalysts (SACs) have well-defined active sites, making them of potential interest for organic synthesis1-4. However, the architecture of these mononuclear metal species stabilized on solid supports may not be optimal for catalysing complex molecular transformations owing to restricted spatial environment and electronic quantum states5,6. Here we report a class of heterogeneous geminal-atom catalysts (GACs), which pair single-atom sites in specific coordination and spatial proximity. Regularly separated nitrogen anchoring groups with delocalized π-bonding nature in a polymeric carbon nitride (PCN) host7 permit the coordination of Cu geminal sites with a ground-state separation of about 4 Å at high metal density8. The adaptable coordination of individual Cu sites in GACs enables a cooperative bridge-coupling pathway through dynamic Cu-Cu bonding for diverse C-X (X = C, N, O, S) cross-couplings with a low activation barrier. In situ characterization and quantum-theoretical studies show that such a dynamic process for cross-coupling is triggered by the adsorption of two different reactants at geminal metal sites, rendering homo-coupling unfeasible. These intrinsic advantages of GACs enable the assembly of heterocycles with several coordination sites, sterically congested scaffolds and pharmaceuticals with highly specific and stable activity. Scale-up experiments and translation to continuous flow suggest broad applicability for the manufacturing of fine chemicals.

2.
Nature ; 604(7907): 779-785, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418679

RESUMO

Adhesion G protein-coupled receptors (aGPCRs) are essential for a variety of physiological processes such as immune responses, organ development, cellular communication, proliferation and homeostasis1-7. An intrinsic manner of activation that involves a tethered agonist in the N-terminal region of the receptor has been proposed for the aGPCRs8,9, but its molecular mechanism remains elusive. Here we report the G protein-bound structures of ADGRD1 and ADGRF1, which exhibit many unique features with regard to the tethered agonism. The stalk region that proceeds the first transmembrane helix acts as the tethered agonist by forming extensive interactions with the transmembrane domain; these interactions are mostly conserved in ADGRD1 and ADGRF1, suggesting that a common stalk-transmembrane domain interaction pattern is shared by members of the aGPCR family. A similar stalk binding mode is observed in the structure of autoproteolysis-deficient ADGRF1, supporting a cleavage-independent manner of receptor activation. The stalk-induced activation is facilitated by a cascade of inter-helix interaction cores that are conserved in positions but show sequence variability in these two aGPCRs. Furthermore, the intracellular region of ADGRF1 contains a specific lipid-binding site, which proves to be functionally important and may serve as the recognition site for the previously discovered endogenous ADGRF1 ligand synaptamide. These findings highlight the diversity and complexity of the signal transduction mechanisms of the aGPCRs.


Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Ligantes , Proteínas Oncogênicas/agonistas , Proteínas Oncogênicas/metabolismo , Ligação Proteica , Domínios Proteicos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo
3.
Proteomics ; : e2300393, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430206

RESUMO

Prostate cancer (PCa) is one of the leading causes of cancer morbidity and mortality in men. Metastasis is the main cause of PCa-associated death. Recent evidence indicated a significant reduction in PCa mortality associated with higher ω-3 polyunsaturated fatty acids (PUFAs) consumption. However, the underlying mechanisms remained elusive. In this study, we applied global acetylome profiling to study the effect of fatty acids treatment. Results indicated that oleic acid (OA, monounsaturated fatty acid, MUFA, 100 µM) elevates while EPA (eicosapentaenoic acid, 100 µM) reduces the acetyl-CoA level, which alters the global acetylome. After treatment, two crucial cell motility regulators, PFN1 and FLNA, were found with altered acetylation levels. OA increased the acetylation of PFN1 and FLNA, whereas EPA decreased PFN1 acetylation level. Furthermore, OA promotes while EPA inhibits PCa migration and invasion. Immunofluorescence assay indicated that EPA impedes the formation of lamellipodia or filopodia through reduced localization of PFN1 and FLNA to the leading edge of cells. Therefore, perturbed acetylome may be one critical step in fatty acid-affected cancer cell motility. This study provides some new insights into the response of ω-3 PUFAs treatment and a better understanding of cancer cell migration and invasion modulation.

4.
J Intern Med ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38924246

RESUMO

OBJECTIVES: Our study aimed to investigate the distinct clinical patterns of seronegative IgG4-related disease (IgG4-RD) patients. METHODS: We retrospectively enrolled 698 treatment-naïve IgG4-RD patients in this study. Patients were divided into four different subgroups according to their baseline serum IgG4 levels. The distinct clinical patterns of seronegative IgG4-RD patients were revealed through the comparison of baseline clinical data and disease prognosis among the different subgroups. COX regression analyses were used to investigate the risk factors for disease relapse and to construct the nomogram model. RESULTS: Seronegative IgG4-RD patients account for a minority of IgG4-RD patients (49/698, 7.02%). The proportions of seronegative IgG-RD patients in our study and several Asian cohorts were significantly lower than those of the European and American cohorts. Seronegative IgG4-RD patients got lower serum IgG levels (p < 0.0001), lower eosinophil count (p < 0.0001), lower serum IgE levels (p < 0.0001)), lower IgG4-RD responder index (RI) scores (p < 0.0001), and fewer affected organ numbers (p < 0.0001) compared with other subgroups, whereas they were more likely to manifest fibrotic type with some special organ involvement. Younger age at onset, GCs monotherapy, elevated C-reactive protein level, and elevated erythrocyte sedimentation rate level are the risk factors for the disease relapse of seronegative IgG4-RD patients. An effective nomogram model predicting disease relapse of seronegative IgG4-RD patients was constructed. Seronegative IgG4-RD patients with scores >84.65 at baseline were susceptible to suffering from disease relapse. CONCLUSIONS: Distinct clinical features and multiple risk factors for disease relapse of seronegative IgG4-RD patients have been revealed in this study. A nomogram model was constructed to effectively predict disease relapse during the follow-up period.

5.
PLoS Pathog ; 18(6): e1010576, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35679251

RESUMO

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), serving as the viral persistence form and transcription template of HBV infection, hijacks host histone and non-histone proteins to form a minichromosome and utilizes posttranslational modifications (PTMs) "histone code" for its transcriptional regulation. HBV X protein (HBx) is known as a cccDNA transcription activator. In this study we established a dual system of the inducible reporter cell lines modelling infection with wildtype (wt) and HBx-null HBV, both secreting HA-tagged HBeAg as a semi-quantitative marker for cccDNA transcription. The cccDNA-bound histone PTM profiling of wt and HBx-null systems, using chromatin immunoprecipitation coupled with quantitative PCR (ChIP-qPCR), confirmed that HBx is essential for maintenance of cccDNA at transcriptionally active state, characterized by active histone PTM markers. Differential proteomics analysis of cccDNA minichromosome established in wt and HBx-null HBV cell lines revealed group-specific hits. One of the hits in HBx-deficient condition was a non-histone host DNA-binding protein high mobility group box 1 (HMGB1). Its elevated association to HBx-null cccDNA was validated by ChIP-qPCR assay in both the HBV stable cell lines and infection systems in vitro. Furthermore, experimental downregulation of HMGB1 in HBx-null HBV inducible and infection models resulted in transcriptional re-activation of the cccDNA minichromosome, accompanied by a switch of the cccDNA-associated histones to euchromatic state with activating histone PTMs landscape and subsequent upregulation of cccDNA transcription. Mechanistically, HBx interacts with HMGB1 and prevents its binding to cccDNA without affecting the steady state level of HMGB1. Taken together, our results suggest that HMGB1 is a novel host restriction factor of HBV cccDNA with epigenetic silencing mechanism, which can be counteracted by viral transcription activator HBx.


Assuntos
Proteína HMGB1 , Hepatite B , DNA Circular/genética , DNA Circular/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Epigênese Genética , Proteína HMGB1/genética , Células Hep G2 , Vírus da Hepatite B/metabolismo , Histonas/metabolismo , Humanos , Transativadores , Fatores de Transcrição/metabolismo , Proteínas Virais Reguladoras e Acessórias , Replicação Viral/genética
6.
Hepatology ; 77(4): 1106-1121, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35344606

RESUMO

BACKGROUND AND AIMS: Hepatocarcinogenesis goes through HCC progenitor cells (HcPCs) to fully established HCC, and the mechanisms driving the development of HcPCs are still largely unknown. APPROACH AND RESULTS: Proteomic analysis in nonaggregated hepatocytes and aggregates containing HcPCs from a diethylnitrosamine-induced HCC mouse model was screened using a quantitative mass spectrometry-based approach to elucidate the dysregulated proteins in HcPCs. The heterotrimeric G stimulating protein α subunit (GαS) protein level was significantly increased in liver cancer progenitor HcPCs, which promotes their response to oncogenic and proinflammatory cytokine IL-6 and drives premalignant HcPCs to fully established HCC. Mechanistically, GαS was located at the membrane inside of hepatocytes and acetylated at K28 by acetyltransferase lysine acetyltransferase 7 (KAT7) under IL-6 in HcPCs, causing the acyl protein thioesterase 1-mediated depalmitoylation of GαS and its cytoplasmic translocation, which were determined by GαS K28A mimicking deacetylation or K28Q mimicking acetylation mutant mice and hepatic Kat7 knockout mouse. Then, cytoplasmic acetylated GαS associated with signal transducer and activator of transcription 3 (STAT3) to impede its interaction with suppressor of cytokine signaling 3, thus promoting in a feedforward manner STAT3 phosphorylation and the response to IL-6 in HcPCs. Clinically, GαS, especially K28-acetylated GαS, was determined to be increased in human hepatic premalignant dysplastic nodules and positively correlated with the enhanced STAT3 phosphorylation, which were in accordance with the data obtained in mouse models. CONCLUSIONS: Malignant progression of HcPCs requires increased K28-acetylated and cytoplasm-translocated GαS, causing enhanced response to IL-6 and driving premalignant HcPCs to fully established HCC, which provides mechanistic insight and a potential target for preventing hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Lisina Acetiltransferases , Humanos , Camundongos , Animais , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Interleucina-6/metabolismo , Proteômica , Citoplasma/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Lisina Acetiltransferases/metabolismo , Fator de Transcrição STAT3/metabolismo , Histona Acetiltransferases/metabolismo
7.
Opt Lett ; 49(5): 1169-1172, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426965

RESUMO

The bound states in the continuum (BICs) have attracted much attention in designing metasurface due to their high Q-factor and effectiveness in suppressing radiational loss. Here we report on the realization of the third harmonic generation (THG) at a near-ultraviolet wavelength (343 nm) via accidental BICs in a metasurface. The absolute conversion efficiency of the THG reaches 1.13 × 10-5 at a lower peak pump intensity of 0.7 GW/cm2. This approach allows the generation of an unprecedentedly high nonlinear conversion efficiency with simple structures.

8.
J Pathol ; 260(1): 43-55, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36752189

RESUMO

Neuroendocrine (NE) cells comprise ~1% of epithelial cells in benign prostate and prostatic adenocarcinoma (PCa). However, they become enriched in hormonally treated and castration-resistant PCa (CRPC). In addition, close to 20% of hormonally treated tumors recur as small cell NE carcinoma (SCNC), composed entirely of NE cells, which may be the result of clonal expansion or lineage plasticity. Since NE cells do not express androgen receptors (ARs), they are resistant to hormonal therapy and contribute to therapy failure. Here, we describe the identification of glypican-3 (GPC3) as an oncofetal cell surface protein specific to NE cells in prostate cancer. Functional studies revealed that GPC3 is critical to the viability of NE tumor cells and tumors displaying NE differentiation and that it regulates calcium homeostasis and signaling. Since our results demonstrate that GPC3 is specifically expressed by NE cells, patients with confirmed SCNC may qualify for GPC3-targeted therapy which has been developed in the context of liver cancer and displays minimal toxicity due to its tumor-specific expression. © 2023 The Pathological Society of Great Britain and Ireland.


Assuntos
Adenocarcinoma , Células Neuroendócrinas , Neoplasias da Próstata , Masculino , Humanos , Células Neuroendócrinas/metabolismo , Células Neuroendócrinas/patologia , Glipicanas/metabolismo , Adenocarcinoma/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Próstata/patologia , Biomarcadores/metabolismo
9.
Sleep Breath ; 28(3): 1293-1301, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38386249

RESUMO

PURPOSE: Sleep apnea-specific hypoxic burden (SASHB) is a polysomnographic metric that comprehensively measures the degree of nocturnal desaturation caused by obstructive sleep apnea. This research was conducted to elucidate the relationship between SASHB and coronary artery disease (CAD) severity. METHODS: We carried out a prospective study of hospitalized patients with CAD of unstable angina who were expected to undergo invasive coronary angiography at Beijing Anzhen Hospital from February to September 2023. SASHB values were calculated using a self-programmed C + + program. Multivariable logistic regression analysis was applied to identify the association between SASHB and the prevalence of severe CAD, documented by the Gensini Score, and the SYNTAX (Synergy between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) Score. RESULTS: This study enrolled 137 patients with a median age of 59 years, 96 (70.1%) of whom were male. A total of 125 (91.2%) patients had coronary stenosis of ≥ 50% in at least one location. Patients with a high SASHB of ≥ 18% min/h had a significantly higher Gensini Score (32.0 vs. 18.5, P = 0.002) and SYNTAX Score (14.0 vs. 7.0, P = 0.002) than those with a low SASHB. After adjusting for multiple covariates, a high SASHB was significantly associated with the prevalence of severe CAD, determined by a Gensini Score ≥ 21 (OR 2.67, P = 0.008) or a SYNTAX Score > 22 (OR 4.03, P = 0.016). CONCLUSION: Our findings revealed a robust and independent association between SASHB and CAD severity in patients with unstable angina, highlighting the potential value of SASHB as a predictor of risk and a target for interventions aimed at preventing cardiovascular diseases. TRIAL REGISTRATION: Chinese Clinical Trial Registry No. ChiCTR2300067991 on February 2, 2023.


Assuntos
Doença da Artéria Coronariana , Hipóxia , Índice de Gravidade de Doença , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Doença da Artéria Coronariana/epidemiologia , Estudos Prospectivos , Idoso , Hipóxia/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Polissonografia , Angiografia Coronária
10.
J Virol ; 96(2): e0136021, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34705558

RESUMO

Hepatitis B virus (HBV) utilizes host DNA repair mechanisms to convert viral relaxed circular DNA (rcDNA) into a persistent viral genome, the covalently closed circular DNA (cccDNA). To identify host factors involved in cccDNA formation, we developed an unbiased approach to discover proteins involved in cccDNA formation by precipitating nuclear rcDNA from induced HepAD38 cells and identifying the coprecipitated proteins by mass spectrometry. DNA damage binding protein 1 (DDB1) surfaced as a hit, coinciding with our previously reported short hairpin RNA (shRNA) screen in which shRNA-DDB1 in HepDES19 cells reduced cccDNA production. DDB1 binding to nuclear rcDNA was confirmed in HepAD38 cells via ChIP-qPCR. DDB1 and DNA damage binding protein 2 (DDB2) form the UV-DDB complex, and the latter senses DNA damage to initiate the global genome nucleotide excision repair (GG-NER) pathway. To investigate the role of the DDB complex in cccDNA formation, DDB2 was knocked out in HepAD38 and HepG2-NTCP cells. In both knockout cell lines, cccDNA formation was stunted significantly, and in HepG2-NTCP-DDB2 knockout cells, downstream indicators of cccDNA such as HBV RNA, HBcAg, and HBeAg were similarly reduced. Knockdown of DDB2 in HBV-infected HepG2-NTCP cells and primary human hepatocytes (PHH) also resulted in cccDNA reduction. Transcomplementation of wild-type DDB2 in HepG2-NTCP-DDB2 knockout cells rescued cccDNA formation and its downstream indicators. However, ectopic expression of DDB2 mutants deficient in DNA binding, DDB1 binding, or ubiquitination failed to rescue cccDNA formation. Our study thus suggests an integral role of UV-DDB, specifically DDB2, in the formation of HBV cccDNA. IMPORTANCE Serving as a key viral factor for chronic hepatitis B virus (HBV) infection, HBV covalently closed circular DNA (cccDNA) is formed in the cell nucleus from viral relaxed circular DNA (rcDNA) by hijacking host DNA repair machinery. Previous studies have identified several host DNA repair factors involved in cccDNA formation through hypothesis-driven research with some help from RNA interference (RNAi) screening and/or biochemistry approaches. To enrich the landscape of tools for discovering host factors responsible for rcDNA-to-cccDNA conversion, we developed an rcDNA immunoprecipitation paired mass spectrometry assay, which allowed us to pull down nuclear rcDNA in its transitional state to cccDNA and observe the associated host factors. From this assay, we discovered a novel relationship between the UV-DDB complex and cccDNA formation, providing a proof of concept for a more direct discovery of novel HBV DNA-host interactions that can be exploited to develop new cccDNA-targeting antivirals.


Assuntos
DNA Circular/metabolismo , DNA Viral/metabolismo , Proteínas de Ligação a DNA/metabolismo , Vírus da Hepatite B/fisiologia , Linhagem Celular , Núcleo Celular/metabolismo , Núcleo Celular/virologia , Replicação do DNA , Proteínas de Ligação a DNA/genética , Antígenos da Hepatite B/metabolismo , Vírus da Hepatite B/metabolismo , Humanos , Ligação Proteica , Proteômica , RNA Viral/metabolismo , Ubiquitinação , Replicação Viral
11.
New Phytol ; 237(1): 265-278, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36131553

RESUMO

Caterpillar oral secretion (OS) contains active molecules that modulate plant defense signaling. We isolated an effector-like protein (Highly Accumulated Secretory Protein 1, HAS1) from cotton bollworm (Helicoverpa armigera) that is the most highly accumulated secretory protein of the nondigestive components in OS and belongs to venom R-like protein. Elimination of HAS1 by plant-mediated RNA interference reduced the suppression of OS on the defense response in plants. Plants expressing HAS1 are more susceptible to insect herbivory accompanied by the reduced expressions of multiple defense genes. HAS1 binds to the basic helix-loop-helix (bHLH) transcription factors, including GoPGF involved in pigmented gland formation and defense compounds biosynthesis in cotton and MYC3/MYC4 the main regulators in jasmonate (JA) signaling in Arabidopsis. The binding activity is required for HAS1 to inhibit the activation of bHLHs on plant defense gene expressions. Together with our previous study that another venom R-like protein HARP1 in cotton bollworm OS blocks JA signaling by interacting with JASMONATE-ZIM-domain repressors, we conclude that the venom R-like proteins in OS interfere with plant defense in a dual suppression manner. Considering the venom proteins in parasitic wasp assault the immune system of its host animal, our investigation reveals their conserved function in carnivorous and herbivorous insects.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Mariposas , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Transativadores/metabolismo , Proteínas Repressoras/metabolismo , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Plantas/metabolismo , Gossypium/genética , Gossypium/metabolismo
12.
Rheumatology (Oxford) ; 62(2): 946-957, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35713502

RESUMO

OBJECTIVES: Whether naive CD4+ T cells are dysregulated and associated with the overactivation of CD4+ T cells in primary SS (pSS) remains unclear. We aimed to explore the role and underlying mechanism of naive CD4+ T cells in pSS. METHODS: We examined the activation, proliferation and differentiation of naive CD4+ T cells from pSS patients and healthy controls. Differentially expressed genes were identified using RNA sequencing, and were overexpressed or silenced to determine the gene regulating follicular helper T (Tfh) cells. Assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) with chromatin immunoprecipitation with high-throughput sequencing (ChIP-seq) was performed to explore the epigenetic mechanism. Naive CD4+ T cells were treated with pSS-related cytokines to explore the upstream signalling pathway. RESULTS: pSS naive CD4+ T cells had higher potentials of activation, proliferation and differentiation towards Tfh cells. Thymocyte selection-associated high mobility group box protein (TOX) was upregulated in pSS naive CD4+ T cells and promoted T cell activation and Tfh cell polarization. TOX silencing in pSS naive CD4+ T cells downregulated B cell lymphoma 6 (BCL6) expression and altered levels of multiple Tfh-associated genes. ChIP-seq analysis implied that TOX bound to the BCL6 locus, where there were accessible regions found by ATAC-seq. IFN-α induced TOX overexpression, which was attenuated by Janus kinase (JAK) and signal transducer and activator of transcription 1 (STAT1) inhibitors. CONCLUSION: Our data suggest that TOX in pSS naive CD4+ T cells is upregulated, which facilitates Tfh cell differentiation. Mechanistically, IFN-α induces TOX overexpression in naive CD4+ T cells through JAK-STAT1 signalling and TOX regulates BCL6 expression. Therefore, IFN-α-JAK-STAT1 signalling and TOX might be potential therapeutic targets in pSS.


Assuntos
Síndrome de Sjogren , Células T Auxiliares Foliculares , Humanos , Células T Auxiliares Foliculares/patologia , Linfócitos T Auxiliares-Indutores/metabolismo , Síndrome de Sjogren/metabolismo , Diferenciação Celular/genética , Linfócitos T CD4-Positivos
13.
Opt Lett ; 48(8): 2002-2005, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37058627

RESUMO

Smith-Purcell radiation (SPR) refers to the far-field, strong, spike radiation generated by the interaction of the evanescent Coulomb field of the moving charged particles and the surrounding medium. In applying SPR for particle detection and nanoscale on-chip light sources, wavelength tunability is desired. Here we report on tunable SPR achieved by moving an electron beam parallel to a two-dimensional (2D) metallic nanodisk array. By in-plane rotating the nanodisk array, the emission spectrum of the SPR splits into two peaks, with the shorter-wavelength peak blueshifted and the longer-wavelength one redshifted by increasing the tuning angle. This effect originates from the fact that the electrons fly effectively over a one-dimensional (1D) quasicrystal projected from the surrounding 2D lattice, and the wavelength of SPR is modulated by quasiperiodic characteristic lengths. The experimental data are in agreement with the simulated ones. We suggest that this tunable radiation provides free-electron-driven tunable multiple photon sources at the nanoscale.

14.
Nat Chem Biol ; 17(12): 1230-1237, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34556863

RESUMO

Cholecystokinin receptors, CCKAR and CCKBR, are important neurointestinal peptide hormone receptors and play a vital role in food intake and appetite regulation. Here, we report three crystal structures of the human CCKAR in complex with different ligands, including one peptide agonist and two small-molecule antagonists, as well as two cryo-electron microscopy structures of CCKBR-gastrin in complex with Gi2 and Gq, respectively. These structures reveal the recognition pattern of different ligand types and the molecular basis of peptide selectivity in the cholecystokinin receptor family. By comparing receptor structures in different conformational states, a stepwise activation process of cholecystokinin receptors is proposed. Combined with pharmacological data, our results provide atomic details for differential ligand recognition and receptor activation mechanisms. These insights will facilitate the discovery of potential therapeutics targeting cholecystokinin receptors.


Assuntos
Devazepida/química , Receptores da Colecistocinina/química , Sequência de Aminoácidos , Microscopia Crioeletrônica , Cristalização , Humanos , Ácidos Indolacéticos/química , Ligantes , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Receptores da Colecistocinina/genética , Relação Estrutura-Atividade , Tiazóis/química
15.
Mol Psychiatry ; 27(4): 2095-2105, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35115700

RESUMO

The ability to remember conspecifics is critical for adaptive cognitive functioning and social communication, and impairments of this ability are hallmarks of autism spectrum disorders (ASDs). Although hippocampal ventral CA1 (vCA1) neurons are known to store social memories, how their activities are coordinated remains unclear. Here we show that vCA1 social memory neurons, characterized by enhanced activity in response to memorized individuals, were preferentially reactivated during sharp-wave ripples (SPW-Rs). Spike sequences of these social replays reflected the temporal orders of neuronal activities within theta cycles during social experiences. In ASD model Shank3 knockout mice, the proportion of social memory neurons was reduced, and neuronal ensemble spike sequences during SPW-Rs were disrupted, which correlated with impaired discriminatory social behavior. These results suggest that SPW-R-mediated sequential reactivation of neuronal ensembles is a canonical mechanism for coordinating hippocampus-dependent social memories and its disruption underlie the pathophysiology of social memory defects associated with ASD.


Assuntos
Transtorno Autístico , Amnésia , Animais , Hipocampo/fisiologia , Camundongos , Proteínas dos Microfilamentos , Proteínas do Tecido Nervoso , Neurônios/fisiologia
16.
Helicobacter ; 28(2): e12953, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36738099

RESUMO

BACKGROUND: High-dose dual therapy (HDDT) is an emerging and promising therapeutic regime for Helicobacter pylori (H. pylori) eradication. However, the pharmacokinetics of the components of HDDT, amoxicillin and proton pump inhibitor, are likely to be affected by body size. In this study, we aimed to find out the impact of body size on the efficacy of HDDT. METHODS: We collected the medical data of 385 treatment-naive patients infected with H. pylori who received HDDT (esomeprazole 20 mg and amoxicillin 750 mg four times daily) for 14 days from July 2020 to December 2021. The associations among the eradication efficacy, adverse events, and variables (sex, age, height, body weight, body mass index (BMI), body surface area (BSA), smoking, drinking, etc.) were analyzed respectively in our study. Among these factors, continuous variables were classified into categorical variables using the cut-off values which were calculated by receiver operating characteristic analysis. RESULTS: The eradication rate of HDDT was 89.9%. There were 55 (14.3%) patients who occurred adverse events during the treatment. Patients with height <170.5 cm, body weight <60.5 kg, BMI <20.55 kg/m2 , BSA <1.69 m2 had a higher eradication rate (92.1% vs. 84.0%, 93.1% vs. 86.8%, 96.0% vs. 87.8%, 93.4% vs. 84.8%, all p < .05). The multivariate analysis showed that BSA ≥1.69 m2 (OR 2.53, 95% CI: 1.28-4.99, p = .007) was the only independent predictor of eradication failure. CONCLUSION: HDDT could achieve better eradication efficacy in patients with small BSA. Clinicians should be aware of the impact of BSA on the H. pylori eradication rate and pay more attention to patients with large BSA.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Quimioterapia Combinada , Amoxicilina/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Tamanho Corporal , Peso Corporal , Resultado do Tratamento , Claritromicina/uso terapêutico
17.
Cell Mol Biol (Noisy-le-grand) ; 69(8): 89-95, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37715416

RESUMO

Systematic evaluation of the consistency between circulating tumor DNA (ctDNA) in plasma and tumor tissue samples in mutations in non-small cell lung cancer (NSCLC) patients. To collect publicly published literature from numerous important international medical databases through computer retrieval. To compare the differences in literature data related to gene mutations between plasma ctDNA and tumor tissue samples, a meta-analysis was performed using Stata 12.0 software while taking into account the inclusion and exclusion criteria. This article includes a total of 15 research data and collected data reports from 15 groups of NSCLC patients. The results are displayed using tissue samples as the gold standard. The Pearson correlation coefficients of sensitivity and specificity were used to calculate rho=0.044, and P=0.893. The Q-test found poor homogeneity and high heterogeneity in sensitivity and specificity among research data from various literature studies (I2>50%, P<0.1). The area under the SROC curve is 0.97 (95% CI: 0.96~0.99). The small sample subgroup has high heterogeneity, and the combined diagnosis effect size is 26[6~111], lower than the large sample subgroup 185320 [0~2.7×1012]. When taking 200 as the cut-off point, the combined effect size of the small sample subgroup is 46 [12~183], still lower than that of the large sample subgroup 429 [52~3574]. From this, it can be concluded that the consistency of small-sample studies is higher than the quality of large-sample studies, and the heterogeneity is relatively low. From the perspective of mutation types, the heterogeneity of literature with EGFR gene mutations alone is higher than that of literature with non-EGFR mutations alone, and the consistency is lower. The consistency of using plasma ctDNA to detect mutations in NSCLC patients with tumor tissue samples is influenced by the type of mutation gene and sample size measured by the patient, and there is a significant bias in related studies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Mutação/genética , Bases de Dados Factuais , Plasma
18.
Biomed Eng Online ; 22(1): 45, 2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37179307

RESUMO

PURPOSE: This study aimed to develop an interpretable machine learning model to predict the onset of myopia based on individual daily information. METHOD: This study was a prospective cohort study. At baseline, non-myopia children aged 6-13 years old were recruited, and individual data were collected through interviewing students and parents. One year after baseline, the incidence of myopia was evaluated based on visual acuity test and cycloplegic refraction measurement. Five algorithms, Random Forest, Support Vector Machines, Gradient Boosting Decision Tree, CatBoost and Logistic Regression were utilized to develop different models and their performance was validated by area under curve (AUC). Shapley Additive exPlanations was applied to interpret the model output on the individual and global level. RESULT: Of 2221 children, 260 (11.7%) developed myopia in 1 year. In univariable analysis, 26 features were associated with the myopia incidence. Catboost algorithm had the highest AUC of 0.951 in the model validation. The top 3 features for predicting myopia were parental myopia, grade and frequency of eye fatigue. A compact model using only 10 features was validated with an AUC of 0.891. CONCLUSION: The daily information contributed reliable predictors for childhood's myopia onset. The interpretable Catboost model presented the best prediction performance. Oversampling technology greatly improved model performance. This model could be a tool in myopia preventing and intervention that can help identify children who are at risk of myopia, and provide personalized prevention strategies based on contributions of risk factors to the individual prediction result.


Assuntos
Miopia , Refração Ocular , Criança , Humanos , Adolescente , Estudos Prospectivos , Miopia/diagnóstico , Miopia/epidemiologia , Testes Visuais , Fatores de Risco
19.
Bioorg Chem ; 138: 106623, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37295240

RESUMO

Fangchinoline (Fan) are extracted from the traditional Chinese medicine Stephania tetrandra S., which is a bis-benzyl isoquinoline alkaloids with anti-tumor activity. Therefore, 25 novel Fan derivatives have been synthesized and evaluated for their anti-cancer activity. In CCK-8 assay, these fangchinoline derivatives displayed higher proliferation inhibitory activity on six tumor cell lines than the parental compound. Compared to the parent Fan, compound 2h presented the anticancer activity against most cancer cells, especially A549 cells, with an IC50 value of 0.26 µM, which was 36.38-fold, and 10.61-fold more active than Fan and HCPT, respectively. Encouragingly, compound 2h showed low biotoxicity to the human normal epithelial cell BEAS-2b with an IC50 value of 27.05 µM. The results indicated compound 2h remarkably inhibited the cell migration by decreasing MMP-2 and MMP-9 expression and inhibited the proliferation of A549 cells by arresting the G2/M cell cycle. Meanwhile, compound 2h could also induce A549 cell apoptosis by promoting endogenous pathways of mitochondrial regulation. In nude mice presented that the growth of tumor tissues was markedly inhibited by the consumption of compound 2h in a dose-dependent manner, and it was found that compound 2h could inhibit the mTOR/PI3K/AKT pathway in vivo. In docking analysis, high affinity interaction between 2h and PI3K was responsible for drastic kinase inhibition by the compound. To conclude, this derivative compound may be useful as a potent anti-cancer agent for treatment of NSCLC.


Assuntos
Antineoplásicos , Benzilisoquinolinas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Camundongos , Animais , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos Nus , Neoplasias Pulmonares/metabolismo , Proliferação de Células , Benzilisoquinolinas/farmacologia , Benzilisoquinolinas/uso terapêutico , Linhagem Celular Tumoral , Apoptose , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
20.
BMC Pulm Med ; 23(1): 415, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907909

RESUMO

OBJECTIVES: The incidence of multiple primary lung cancer (MPLC) has increased in recent years. The risk factors of MPLC are not well studied, especially in the Asian population. This case-control study investigated the association between a family history of cancer and MPLC risk. METHODS: We used data from people who surgically confirmed MPLC with at least 2 nodes of Fujian Medical University Union Hospital and matched 1:2 normal individuals as controls between 2016 and 2017. Information on age, sex, lifestyle, personal history, and family history of cancer was collected using a self-administered questionnaire, and odds ratios (OR) were estimated using unconditional logistic regression. RESULTS: We included 2 104 patients. In total, 321 patients with histologically confirmed MPLC and 642 healthy controls were studied. The significantly higher ratio of current smokers was observed for the cases than the controls (54.1% vs. 30.0%). A family history of LC in first-degree relatives of the cases reported a significantly higher proportion than in the controls (15.3% vs. 8.6%). Family history of all cancers and LC significantly increased the risk of MPLC (OR = 1.64, P = 0.009 and OR = 2.59, P = 0.000, respectively). The multivariate analysis identified a significantly increased risk of MPLC (OR = 2.45, P = 0.000) associated with parents and siblings influenced by LC history. The younger age (aged < 55 years) of LC cases at diagnosis exhibited a significantly increased risk of MPLC (OR = 2.39, P = 0.000). A significant association with a family history of LC was found for male squamous carcinoma and male adenocarcinoma (OR = 1.59, p = 0.037 and OR = 1.64, p = 0.032, respectively). A positive association with LC history was only observed for female adenocarcinoma (OR = 2.23, p = 0.028). The risk of MPLC was not significantly associated with A family history of cancers in non-smokers (OR = 0.91, P = 0.236). Ever-smokers with a positive family history of cancer or LC had a significantly elevated risk of MPLC (OR = 4.01, P = 0.000 and OR = 6.49, P = 0.000, respectively). We also observed a very elevated risk for smokers with no family history (OR = 3.49, P = 0.000). Such a positive association was also observed in ever-smokers with no family history of LC (OR = 3.55, P = 0.000). Adenocarcinoma in females was prevalent and significantly associated with a family history of LC in risk of MPLC compared with other histologic subtypes. CONCLUSIONS: Our findings suggest an association between a family history of LC and MPLC risk among an Asian population. Smoking status and family history of LC have a synergistic effect on MPLC. These findings indicate that MPLC exhibits familiar aggregation and that inherited genetic susceptibility may contribute to the development of MPLC.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , Neoplasias Primárias Múltiplas , Humanos , Masculino , Feminino , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Estudos de Casos e Controles , Fumar/epidemiologia , Fumar/efeitos adversos , Fatores de Risco , Adenocarcinoma/complicações
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