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1.
Proc Natl Acad Sci U S A ; 121(42): e2406936121, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39388269

RESUMEN

Kirsten rat sarcoma virus (KRAS) mutation is associated with malignant tumor transformation and drug resistance. However, the development of clinically effective targeted therapies for KRAS-mutant cancer has proven to be a formidable challenge. Here, we report that tripartite motif-containing protein 21 (TRIM21) functions as a target of extracellular signal-regulated kinase 2 (ERK2) in KRAS-mutant colorectal cancer (CRC), contributing to regorafenib therapy resistance. Mechanistically, TRIM21 directly interacts with and ubiquitinates v-myc avian myelocytomatosis viral oncogene homolog (c-Myc) at lysine 148 (K148) via K63-linkage, enabling c-Myc to be targeted to the autophagy machinery for degradation, ultimately resulting in the downregulation of enolase 2 expression and inhibition of glycolysis. However, mutant KRAS (KRAS/MT)-driven mitogen-activated protein kinase (MAPK) signaling leads to the phosphorylation of TRIM21 (p-TRIM21) at Threonine 396 (T396) by ERK2, disrupting the interaction between TRIM21 and c-Myc and thereby preventing c-Myc from targeting autophagy for degradation. This enhances glycolysis and contributes to regorafenib resistance. Clinically, high p-TRIM21 (T396) is associated with an unfavorable prognosis. Targeting TRIM21 to disrupt KRAS/MT-driven phosphorylation using the antidepressant vilazodone shows potential for enhancing the efficacy of regorafenib in treating KRAS-mutant CRC in preclinical models. These findings are instrumental for KRAS-mutant CRC treatment aiming at activating TRIM21-mediated selective autophagic degradation of c-Myc.


Asunto(s)
Autofagia , Neoplasias Colorrectales , Compuestos de Fenilurea , Proteínas Proto-Oncogénicas c-myc , Proteínas Proto-Oncogénicas p21(ras) , Piridinas , Ribonucleoproteínas , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Humanos , Autofagia/efectos de los fármacos , Compuestos de Fenilurea/farmacología , Animales , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Piridinas/farmacología , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Ratones , Ribonucleoproteínas/metabolismo , Ribonucleoproteínas/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos , Ensayos Antitumor por Modelo de Xenoinjerto , Proteolisis/efectos de los fármacos , Mutación , Ratones Desnudos
2.
J Immunol ; 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39400236

RESUMEN

Hepatitis B virus (HBV) is the most common chronic viral infection globally, affecting ∼360 million people and causing about 1 million deaths annually due to end-stage liver disease or hepatocellular carcinoma. Current antiviral treatments rarely achieve a functional cure for chronic hepatitis B, highlighting the need for improved monitoring and intervention strategies. This study explores the role of the sphingosine kinase 1 (SphK1)-sphingosine-1-phosphate (S1P) axis in HBV-related liver injury. We investigated the association between serum S1P concentration and HBV DNA levels in chronic hepatitis B patients, finding a significant positive correlation. Additionally, SphK1 was elevated in liver tissues of HBV-positive hepatocellular carcinoma patients, particularly in HBsAg-positive regions. HBV infection models in HepG2-sodium taurocholate cotransporting polypeptide cells confirmed that HBV enhances SphK1 expression and S1P production. Inhibition of HBV replication through antiviral agents and the CRISPR-Cas9 system reduced SphK1 and S1P levels. Further, we identified the transcription factor USF1 as a key regulator of SphK1 expression during HBV infection. USF1 binds to the SphK1 promoter, increasing its transcriptional activity, and is upregulated in response to HBV infection. In vivo studies in mice demonstrated that HBV exposure promotes the expression of USF1 and SphK1-S1P. These findings suggest that the SphK1-S1P axis, regulated by HBV-induced USF1, could serve as a potential biomarker and therapeutic target for HBV-related liver injury.

3.
Nature ; 583(7815): 282-285, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32218527

RESUMEN

The ongoing outbreak of viral pneumonia in China and across the world is associated with a new coronavirus, SARS-CoV-21. This outbreak has been tentatively associated with a seafood market in Wuhan, China, where the sale of wild animals may be the source of zoonotic infection2. Although bats are probable reservoir hosts for SARS-CoV-2, the identity of any intermediate host that may have facilitated transfer to humans is unknown. Here we report the identification of SARS-CoV-2-related coronaviruses in Malayan pangolins (Manis javanica) seized in anti-smuggling operations in southern China. Metagenomic sequencing identified pangolin-associated coronaviruses that belong to two sub-lineages of SARS-CoV-2-related coronaviruses, including one that exhibits strong similarity in the receptor-binding domain to SARS-CoV-2. The discovery of multiple lineages of pangolin coronavirus and their similarity to SARS-CoV-2 suggests that pangolins should be considered as possible hosts in the emergence of new coronaviruses and should be removed from wet markets to prevent zoonotic transmission.


Asunto(s)
Betacoronavirus/genética , Betacoronavirus/aislamiento & purificación , Euterios/virología , Evolución Molecular , Genoma Viral/genética , Homología de Secuencia de Ácido Nucleico , Secuencia de Aminoácidos , Animales , Betacoronavirus/química , Betacoronavirus/clasificación , COVID-19 , China/epidemiología , Quirópteros/virología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/virología , Reservorios de Enfermedades/virología , Genómica , Humanos , Malasia , Pandemias , Filogenia , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Neumonía Viral/virología , Recombinación Genética , SARS-CoV-2 , Alineación de Secuencia , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Zoonosis/virología
4.
Mol Cell ; 70(2): 340-357.e8, 2018 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-29628309

RESUMEN

Whereas the actions of enhancers in gene transcriptional regulation are well established, roles of JmjC-domain-containing proteins in mediating enhancer activation remain poorly understood. Here, we report that recruitment of the JmjC-domain-containing protein 6 (JMJD6) to estrogen receptor alpha (ERα)-bound active enhancers is required for RNA polymerase II recruitment and enhancer RNA production on enhancers, resulting in transcriptional pause release of cognate estrogen target genes. JMJD6 is found to interact with MED12 in the mediator complex to regulate its recruitment. Unexpectedly, JMJD6 is necessary for MED12 to interact with CARM1, which methylates MED12 at multiple arginine sites and regulates its chromatin binding. Consistent with its role in transcriptional activation, JMJD6 is required for estrogen/ERα-induced breast cancer cell growth and tumorigenesis. Our data have uncovered a critical regulator of estrogen/ERα-induced enhancer coding gene activation and breast cancer cell potency, providing a potential therapeutic target of ER-positive breast cancers.


Asunto(s)
Neoplasias de la Mama/enzimología , Proliferación Celular , Receptor alfa de Estrógeno/metabolismo , Histona Demetilasas con Dominio de Jumonji/metabolismo , Complejo Mediador/metabolismo , Proteína-Arginina N-Metiltransferasas/metabolismo , Activación Transcripcional , Animales , Sitios de Unión , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Estradiol/farmacología , Receptor alfa de Estrógeno/agonistas , Receptor alfa de Estrógeno/genética , Femenino , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Células MCF-7 , Complejo Mediador/genética , Ratones Endogámicos BALB C , Ratones Desnudos , Unión Proteica , Transporte de Proteínas , Proteína-Arginina N-Metiltransferasas/genética , Transducción de Señal , Activación Transcripcional/efectos de los fármacos
5.
Nucleic Acids Res ; 52(12): 6811-6829, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38676947

RESUMEN

Protein arginine methyltransferase CARM1 has been shown to methylate a large number of non-histone proteins, and play important roles in gene transcriptional activation, cell cycle progress, and tumorigenesis. However, the critical substrates through which CARM1 exerts its functions remain to be fully characterized. Here, we reported that CARM1 directly interacts with the GATAD2A/2B subunit in the nucleosome remodeling and deacetylase (NuRD) complex, expanding the activities of NuRD to include protein arginine methylation. CARM1 and NuRD bind and activate a large cohort of genes with implications in cell cycle control to facilitate the G1 to S phase transition. This gene activation process requires CARM1 to hypermethylate GATAD2A/2B at a cluster of arginines, which is critical for the recruitment of the NuRD complex. The clinical significance of this gene activation mechanism is underscored by the high expression of CARM1 and NuRD in breast cancers, and the fact that knockdown CARM1 and NuRD inhibits cancer cell growth in vitro and tumorigenesis in vivo. Targeting CARM1-mediated GATAD2A/2B methylation with CARM1 specific inhibitors potently inhibit breast cancer cell growth in vitro and tumorigenesis in vivo. These findings reveal a gene activation program that requires arginine methylation established by CARM1 on a key chromatin remodeler, and targeting such methylation might represent a promising therapeutic avenue in the clinic.


Asunto(s)
Neoplasias de la Mama , Ensamble y Desensamble de Cromatina , Regulación Neoplásica de la Expresión Génica , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2 , Proteína-Arginina N-Metiltransferasas , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/metabolismo , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/genética , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Humanos , Femenino , Animales , Línea Celular Tumoral , Ciclo Celular/genética , Ratones , Metilación , Arginina/metabolismo , Carcinogénesis/genética , Activación Transcripcional
6.
Proc Natl Acad Sci U S A ; 120(13): e2218819120, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36943875

RESUMEN

Certain ciliary transmembrane and membrane-tethered signaling proteins migrate from the ciliary tip to base via retrograde intraflagellar transport (IFT), essential for maintaining their ciliary dynamics to enable cells to sense and transduce extracellular stimuli inside the cell. During this process, the BBSome functions as an adaptor between retrograde IFT trains and these signaling protein cargoes. The Arf-like 13 (ARL13) small GTPase resembles ARL6/BBS3 in facilitating these signaling cargoes to couple with the BBSome at the ciliary tip prior to loading onto retrograde IFT trains for transporting towards the ciliary base, while the molecular basis for how this intricate coupling event happens remains elusive. Here, we report that Chlamydomonas ARL13 only in a GTP-bound form (ARL13GTP) anchors to the membrane for diffusing into cilia. Upon entering cilia, ARL13 undergoes GTPase cycle for shuttling between the ciliary membrane (ARL13GTP) and matrix (ARL13GDP). To achieve this goal, the ciliary membrane-anchored BBS3GTP binds the ciliary matrix-residing ARL13GDP to activate the latter as an ARL13 guanine nucleotide exchange factor. At the ciliary tip, ARL13GTP recruits the ciliary matrix-residing and post-remodeled BBSome as an ARL13 effector to anchor to the ciliary membrane. This makes the BBSome spatiotemporally become available for the ciliary membrane-tethered phospholipase D (PLD) to couple with. Afterward, ARL13GTP hydrolyzes GTP for releasing the PLD-laden BBSome to load onto retrograde IFT trains. According to this model, hedgehog signaling defects associated with ARL13b and BBS3 mutations in humans could be satisfactorily explained, providing us a mechanistic understanding behind BBSome-cargo coupling required for proper ciliary signaling.


Asunto(s)
Síndrome de Bardet-Biedl , Cilios , Humanos , Cilios/metabolismo , Transporte de Proteínas/genética , Síndrome de Bardet-Biedl/genética , Proteínas Hedgehog/metabolismo , Proteínas de la Membrana/metabolismo , Guanosina Trifosfato/metabolismo , Flagelos/metabolismo
7.
Hum Genomics ; 18(1): 111, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39380106

RESUMEN

BACKGROUND: This study aimed to screen southern and southwestern Chinese individuals using expanded carrier screening (ECS), which explores the carrier status of recessively inherited diseases in southern and southwestern China, evaluates the clinical effectiveness of ECS application, and helps recognize high-risk fetuses that may have genetic disorders early in pregnancy, to provide better reproductive guidance. METHODS: ECS for 220 diseases based on next-generation sequencing was performed on 3024 southern and southwestern Chinese individuals (1512 couples). Carrier status was analyzed; genes and loci with high frequencies of variants and on high-risk couples (ARCs) were focused to evaluate the clinical utility of our ECS technology and provide them precise fertility guidance. RESULTS: In total, Pathogenic/likely pathogenic(P/LP) variants were found in 1885 individuals, so the carrier frequency was 62.3%, and 23.2% of the individuals were carriers of multiple diseases. furthermore, 2837 variants were detected, and the average number of P/LP variants carried per subject was 0.938. Additionally, 128 ARCs carried P/LP variants of the same gene, and the theoretical incidence rate in their offspring was as high as 2.12%. CONCLUSION: This study validated the application of our ECS technique for carrier screening in southern China, identifying carrier status and providing accurate carrier frequencies for hundreds of genetic diseases.


Asunto(s)
Tamización de Portadores Genéticos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Femenino , China/epidemiología , Tamización de Portadores Genéticos/métodos , Masculino , Embarazo , Pruebas Genéticas/métodos , Heterocigoto , Estudios de Seguimiento , Adulto , Enfermedades Genéticas Congénitas/genética , Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/epidemiología , Pueblos del Este de Asia
8.
Cell Mol Life Sci ; 81(1): 121, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38457049

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent gastrointestinal malignancies with high mortality worldwide. Emerging evidence indicates that long noncoding RNAs (lncRNAs) are involved in human cancers, including ESCC. However, the detailed mechanisms of lncRNAs in the regulation of ESCC progression remain incompletely understood. LUESCC was upregulated in ESCC tissues compared with adjacent normal tissues, which was associated with gender, deep invasion, lymph node metastasis, and poor prognosis of ESCC patients. LUESCC was mainly localized in the cytoplasm of ESCC cells. Knockdown of LUESCC inhibited cell proliferation, colony formation, migration, and invasion in vitro and suppressed tumor growth in vivo. Mechanistic investigation indicated that LUESCC functions as a ceRNA by sponging miR-6785-5p to enhance NRSN2 expression, which is critical for the malignant behaviors of ESCC. Furthermore, ASO targeting LUESCC substantially suppressed ESCC both in vitro and in vivo. Collectively, these data demonstrate that LUESCC may exerts its oncogenic role by sponging miR-6785-5p to promote NRSN2 expression in ESCC, providing a potential diagnostic marker and therapeutic target for ESCC patients.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , MicroARNs , ARN Largo no Codificante , Humanos , Línea Celular Tumoral , Progresión de la Enfermedad , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas de Esófago/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , MicroARNs/metabolismo , Invasividad Neoplásica/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
9.
Lancet Oncol ; 25(2): 184-197, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38211606

RESUMEN

BACKGROUND: Triple-negative breast cancers display heterogeneity in molecular drivers and immune traits. We previously classified triple-negative breast cancers into four subtypes: luminal androgen receptor (LAR), immunomodulatory, basal-like immune-suppressed (BLIS), and mesenchymal-like (MES). Here, we aimed to evaluate the efficacy and safety of subtyping-based therapy in the first-line treatment of triple-negative breast cancer. METHODS: FUTURE-SUPER is an ongoing, open-label, randomised, controlled phase 2 trial being conducted at Fudan University Shanghai Cancer Center (FUSCC), Shanghai, China. Eligible participants were females aged 18-70 years, with an Eastern Cooperative Oncology Group performance status of 0-1, and histologically confirmed, untreated metastatic or recurrent triple-negative breast cancer. After categorising participants into five cohorts according to molecular subtype and genomic biomarkers, participants were randomly assigned (1:1) with a block size of 4, stratified by subtype, to receive, in 28-day cycles, nab-paclitaxel (100 mg/m2, intravenously on days 1, 8, and 15) alone (control group) or with a subtyping-based regimen (subtyping-based group): pyrotinib (400 mg orally daily) for the LAR-HER2mut subtype, everolimus (10 mg orally daily) for the LAR-PI3K/AKTmut and MES-PI3K/AKTmut subtypes, camrelizumab (200 mg intravenously on days 1 and 15) and famitinib (20 mg orally daily) for the immunomodulatory subtype, and bevacizumab (10 mg/kg intravenously on days 1 and 15) for the BLIS/MES-PI3K/AKTWT subtype. The primary endpoint was investigator-assessed progression-free survival for the pooled subtyping-based group versus the control group in the intention-to-treat population (all randomly assigned participants). Safety was analysed in all patients with safety records who received at least one dose of study drug. This study is registered with ClinicalTrials.gov (NCT04395989). FINDINGS: Between July 28, 2020, and Oct 16, 2022, 139 female participants were enrolled and randomly assigned to the subtyping-based group (n=69) or control group (n=70). At the data cutoff (May 31, 2023), the median follow-up was 22·5 months (IQR 15·2-29·0). Median progression-free survival was significantly longer in the pooled subtyping-based group (11·3 months [95% CI 8·6-15·2]) than in the control group (5·8 months [4·0-6·7]; hazard ratio 0·44 [95% CI 0·30-0·65]; p<0·0001). The most common grade 3-4 treatment-related adverse events were neutropenia (21 [30%] of 69 in the pooled subtyping-based group vs 16 [23%] of 70 in the control group), anaemia (five [7%] vs none), and increased alanine aminotransferase (four [6%] vs one [1%]). Treatment-related serious adverse events were reported for seven (10%) of 69 patients in the subtyping-based group and none in the control group. No treatment-related deaths were reported in either group. INTERPRETATION: These findings highlight the potential clinical benefits of using molecular subtype-based treatment optimisation in patients with triple-negative breast cancer, suggesting a path for further clinical investigation. Phase 3 randomised clinical trials assessing the efficacy of subtyping-based regimens are now underway. FUNDING: National Natural Science Foundation of China, Natural Science Foundation of Shanghai, Shanghai Hospital Development Center, and Jiangsu Hengrui Pharmaceuticals. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Proteínas Proto-Oncogénicas c-akt , Fosfatidilinositol 3-Quinasas/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , China , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
10.
BMC Genomics ; 25(1): 612, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890564

RESUMEN

BACKGROUND: Salt sensitivity of blood pressure (SSBP) is an intermediate phenotype of hypertension and is a predictor of long-term cardiovascular events and death. However, the genetic structures of SSBP are uncertain, and it is difficult to precisely diagnose SSBP in population. So, we aimed to identify genes related to susceptibility to the SSBP, construct a risk evaluation model, and explore the potential functions of these genes. METHODS AND RESULTS: A genome-wide association study of the systemic epidemiology of salt sensitivity (EpiSS) cohort was performed to obtain summary statistics for SSBP. Then, we conducted a transcriptome-wide association study (TWAS) of 12 tissues using FUSION software to predict the genes associated with SSBP and verified the genes with an mRNA microarray. The potential roles of the genes were explored. Risk evaluation models of SSBP were constructed based on the serial P value thresholds of polygenetic risk scores (PRSs), polygenic transcriptome risk scores (PTRSs) and their combinations of the identified genes and genetic variants from the TWAS. The TWAS revealed that 2605 genes were significantly associated with SSBP. Among these genes, 69 were differentially expressed according to the microarray analysis. The functional analysis showed that the genes identified in the TWAS were enriched in metabolic process pathways. The PRSs were correlated with PTRSs in the heart atrial appendage, adrenal gland, EBV-transformed lymphocytes, pituitary, artery coronary, artery tibial and whole blood. Multiple logistic regression models revealed that a PRS of P < 0.05 had the best predictive ability compared with other PRSs and PTRSs. The combinations of PRSs and PTRSs did not significantly increase the prediction accuracy of SSBP in the training and validation datasets. CONCLUSIONS: Several known and novel susceptibility genes for SSBP were identified via multitissue TWAS analysis. The risk evaluation model constructed with the PRS of susceptibility genes showed better diagnostic performance than the transcript levels, which could be applied to screen for SSBP high-risk individuals.


Asunto(s)
Presión Sanguínea , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Presión Sanguínea/genética , Perfilación de la Expresión Génica , Hipertensión/genética , Transcriptoma , Polimorfismo de Nucleótido Simple , Masculino , Medición de Riesgo , Femenino , Cloruro de Sodio Dietético/efectos adversos
11.
J Am Chem Soc ; 146(22): 15473-15478, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38782032

RESUMEN

The synthesis and characterization of a series of polyantimony anionic clusters are reported. The products [(NbCp)2Sb10]2-, [MSb13]3- (M = Ru/Fe), and [MSb15]3- (M = Ru/Fe) were isolated as either K(18-crown-6) or K([2.2.2]-crypt) salts. The Sb10 ring contained in the [(NbCp)2Sb10]2- cluster can be viewed as an extension of two envelope-like cyclo-Sb5 units and represents by far the largest monocyclic all-antimony species. The clusters [MSb13]3- and [MSb15]3- (M = Ru/Fe) illustrate the variability of crown-like Sb8 ring motifs and reveal the fusion of different antimony fragments featuring unique Sb-Sb chain-like units. The reported synthetic approaches involve the fabrication of a variety of distinctive polyantimony anionic clusters, enhancing our understanding of the coordination chemistry of heavier group 15 elements.

12.
J Am Chem Soc ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39331518

RESUMEN

Pure-element cyclic molecules have garnered extensive attention owing to their intriguing structures and promising applications. Among these, carbon-based cyclic molecules such as cyclo[n]carbon (Cn, n = 10-26) and carbon nanotori have ignited significant interest in both experimental and theoretical investigations. However, systematic investigations of analogous cyclic counterparts of heavier main-group elements are limited, with only a few known by theoretical studies. Furthermore, these corresponding cyclic structures lack synthetic examples in the condensed phase, primarily attributed to their high reactivity resulting from lone electron pairs and the absence of electronic delocalization, which typically aids in stabilizing the structure. In this work, we introduce the pioneering synthesis of a pure antimony-based inorganic nanotorus, denoted as Sb688-, facilitated by the incorporation of C60 for oxidation by utilizing wet-chemistry methodologies. The unique nanotorus structure was meticulously examined via single-crystalline X-ray diffraction, unveiling its composition of 68 antimony atoms and forming a tubular structure with approximate dimensions of 18.5 × 18.4 Å2 in a square shape. Theoretical calculations further revealed that the nanotorus structure, characterized by 16 delocalized electrons distributed across eight 3c-2e σ bonds, effectively saturated the eight two-coordinated Sb atoms within the cluster. This study unveils an innovative approach to synthesizing cyclic compounds solely from pure elements, departing from traditional methods dependent on chemical vapor deposition or surface synthesis, and heralds a profound paradigm shift in physical science.

13.
J Am Chem Soc ; 146(5): 2901-2906, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38271666

RESUMEN

Macrocyclic arenes have emerged as pivotal scaffolds in supramolecular chemistry. Despite their significant contributions to molecular recognition and diverse applications, challenges persist in the development of macrocyclic arene-based crystalline materials, particularly in achieving porosity and addressing limitations in adsorption efficiency resulting from the small cavity sizes of existing macrocyclic arenes. In this study, we present the design and synthesis of a novel macrocyclic arene, clamparene (CLP), featuring a rigid backbone, easy synthesis, and a sizable cavity. CLP self-assembles into one-dimensional sub-nanotubes that further organize into a three-dimensional porous framework in the solid state. The crystalline solid of CLP exhibits potential as a porous crystalline adsorbent for various benzene-based contaminants with rapid adsorption kinetics, large uptake amounts, and good recyclability.

14.
Radiology ; 310(3): e232255, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38470237

RESUMEN

Background Large language models (LLMs) hold substantial promise for medical imaging interpretation. However, there is a lack of studies on their feasibility in handling reasoning questions associated with medical diagnosis. Purpose To investigate the viability of leveraging three publicly available LLMs to enhance consistency and diagnostic accuracy in medical imaging based on standardized reporting, with pathology as the reference standard. Materials and Methods US images of thyroid nodules with pathologic results were retrospectively collected from a tertiary referral hospital between July 2022 and December 2022 and used to evaluate malignancy diagnoses generated by three LLMs-OpenAI's ChatGPT 3.5, ChatGPT 4.0, and Google's Bard. Inter- and intra-LLM agreement of diagnosis were evaluated. Then, diagnostic performance, including accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC), was evaluated and compared for the LLMs and three interactive approaches: human reader combined with LLMs, image-to-text model combined with LLMs, and an end-to-end convolutional neural network model. Results A total of 1161 US images of thyroid nodules (498 benign, 663 malignant) from 725 patients (mean age, 42.2 years ± 14.1 [SD]; 516 women) were evaluated. ChatGPT 4.0 and Bard displayed substantial to almost perfect intra-LLM agreement (κ range, 0.65-0.86 [95% CI: 0.64, 0.86]), while ChatGPT 3.5 showed fair to substantial agreement (κ range, 0.36-0.68 [95% CI: 0.36, 0.68]). ChatGPT 4.0 had an accuracy of 78%-86% (95% CI: 76%, 88%) and sensitivity of 86%-95% (95% CI: 83%, 96%), compared with 74%-86% (95% CI: 71%, 88%) and 74%-91% (95% CI: 71%, 93%), respectively, for Bard. Moreover, with ChatGPT 4.0, the image-to-text-LLM strategy exhibited an AUC (0.83 [95% CI: 0.80, 0.85]) and accuracy (84% [95% CI: 82%, 86%]) comparable to those of the human-LLM interaction strategy with two senior readers and one junior reader and exceeding those of the human-LLM interaction strategy with one junior reader. Conclusion LLMs, particularly integrated with image-to-text approaches, show potential in enhancing diagnostic medical imaging. ChatGPT 4.0 was optimal for consistency and diagnostic accuracy when compared with Bard and ChatGPT 3.5. © RSNA, 2024 Supplemental material is available for this article.


Asunto(s)
Nódulo Tiroideo , Humanos , Femenino , Adulto , Nódulo Tiroideo/diagnóstico por imagen , Estudios Retrospectivos , Lenguaje , Redes Neurales de la Computación , Curva ROC
15.
J Transl Med ; 22(1): 316, 2024 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-38549133

RESUMEN

BACKGROUND: Propofol is a widely used anesthetic and sedative, which has been reported to exert an anti-inflammatory effect. TLR4 plays a critical role in coordinating the immuno-inflammatory response during sepsis. Whether propofol can act as an immunomodulator through regulating TLR4 is still unclear. Given its potential as a sepsis therapy, we investigated the mechanisms underlying the immunomodulatory activity of propofol. METHODS: The effects of propofol on TLR4 and Rab5a (a master regulator involved in intracellular trafficking of immune factors) were investigated in macrophage (from Rab5a-/- and WT mice) following treatment with lipopolysaccharide (LPS) or cecal ligation and puncture (CLP) in vitro and in vivo, and peripheral blood monocyte from sepsis patients and healthy volunteers. RESULTS: We showed that propofol reduced membrane TLR4 expression on macrophages in vitro and in vivo. Rab5a participated in TLR4 intracellular trafficking and both Rab5a expression and the interaction between Rab5a and TLR4 were inhibited by propofol. We also showed Rab5a upregulation in peripheral blood monocytes of septic patients, accompanied by increased TLR4 expression on the cell surface. Propofol downregulated the expression of Rab5a and TLR4 in these cells. CONCLUSIONS: We demonstrated that Rab5a regulates intracellular trafficking of TLR4 and that propofol reduces membrane TLR4 expression on macrophages by targeting Rab5a. Our study not only reveals a novel mechanism for the immunomodulatory effect of propofol but also indicates that Rab5a may be a potential therapeutic target against sepsis.


Asunto(s)
Propofol , Sepsis , Ratones , Humanos , Animales , Propofol/farmacología , Propofol/uso terapéutico , Propofol/metabolismo , Receptor Toll-Like 4/metabolismo , Modelos Animales de Enfermedad , Macrófagos/metabolismo , Sepsis/complicaciones , Lipopolisacáridos/farmacología , Lipopolisacáridos/metabolismo
16.
BMC Cancer ; 24(1): 1066, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39210343

RESUMEN

PURPOSE: Bone metastases occur in 50-70% of patients with breast cancer (BC) and result in high mortality. Platelet distribution width (PDW), a commonly used parameter of activated platelets, has been associated with a poor prognosis in BC. We aim to investigate the prognostic role of PDW for bone metastasis in BC patients. METHODS: 515 patients who received BC surgery in the Harbin Medical University Cancer Hospital from July 1, 2016, to December 31, 2017, were reviewed. Patients' characteristics and platelet indices upon enrollment in this study were collected. The Kaplan-Meier method was used to estimate the 5-year bone metastasis incidence. The univariate and multivariate Cox regression analyses were utilized to identify risk factors associated with bone metastasis. RESULTS: The patients with bone metastases exhibited lower PDW levels than the patients without bone metastases. Moreover, decreased PDW was significantly correlated with histologic type, multifocal disease, and lymph node status. In addition, the patients with reduced PDW levels were more likely to develop bone metastasis. Multivariate analysis showed that PDW was an independent predictor for bone metastasis. CONCLUSION: PDW is an independent predictor of bone metastasis in BC. Further research is warranted.


Asunto(s)
Plaquetas , Neoplasias Óseas , Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/sangre , Neoplasias Óseas/secundario , Neoplasias Óseas/sangre , Persona de Mediana Edad , Pronóstico , Plaquetas/patología , Anciano , Estudios Retrospectivos , Adulto , Periodo Preoperatorio , Factores de Riesgo , Recuento de Plaquetas , Estimación de Kaplan-Meier
17.
J Magn Reson Imaging ; 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38205712

RESUMEN

BACKGROUND: Accurate evaluation of the axillary lymph node (ALN) status is needed for determining the treatment protocol for breast cancer (BC). The value of magnetic resonance imaging (MRI)-based tumor heterogeneity in assessing ALN metastasis in BC is unclear. PURPOSE: To assess the value of deep learning (DL)-derived kinetic heterogeneity parameters based on BC dynamic contrast-enhanced (DCE)-MRI to infer the ALN status. STUDY TYPE: Retrospective. SUBJECTS: 1256/539/153/115 patients in the training cohort, internal validation cohort, and external validation cohorts I and II, respectively. FIELD STRENGTH/SEQUENCE: 1.5 T/3.0 T, non-contrast T1-weighted spin-echo sequence imaging (T1WI), DCE-T1WI, and diffusion-weighted imaging. ASSESSMENT: Clinical pathological and MRI semantic features were obtained by reviewing histopathology and MRI reports. The segmentation of the tumor lesion on the first phase of T1WI DCE-MRI images was applied to other phases after registration. A DL architecture termed convolutional recurrent neural network (ConvRNN) was developed to generate the KHimage (kinetic heterogeneity of DCE-MRI image) score that indicated the ALN status in patients with BC. The model was trained and optimized on training and internal validation cohorts, tested on two external validation cohorts. We compared ConvRNN model with other 10 models and the subgroup analyses of tumor size, magnetic field strength, and molecular subtype were also evaluated. STATISTICAL TESTS: Chi-squared, Fisher's exact, Student's t, Mann-Whitney U tests, and receiver operating characteristics (ROC) analysis were performed. P < 0.05 was considered significant. RESULTS: The ConvRNN model achieved area under the curve (AUC) of 0.802 in the internal validation cohort and 0.785-0.806 in the external validation cohorts. The ConvRNN model could well evaluate the ALN status of the four molecular subtypes (AUC = 0.685-0.868). The patients with larger tumor sizes (>5 cm) were more susceptible to ALN metastasis with KHimage scores of 0.527-0.827. DATA CONCLUSION: A ConvRNN model outperformed traditional models for determining the ALN status in patients with BC. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

18.
Arch Microbiol ; 206(2): 63, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38217700

RESUMEN

During the investigations of macrofungi resources in Zhejiang Province, China, an interesting wood rot fungus was collected. Based on morphological and molecular phylogenetic studies, it is described as a new species, Anthracophyllum sinense. A. sinense is characterized by its sessile, charcoal black and pleurotoid pileus, sparse lamellae occasionally branching, clavate basidia with long sterigmata [(3-)6-7(-8) µm], and non-heteromorphous cystidia. A. sinense establishes a separate lineage close to A. archeri and A. lateritium in the phylogenetic tree.


Asunto(s)
Agaricales , Basidiomycota , Filogenia , ADN de Hongos/genética , China
19.
Pediatr Res ; 95(1): 227-232, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37580551

RESUMEN

BACKGROUND: children who undergo CPB operations are at an elevated risk of infection due to immunosuppression. This study aims to investigate the association between lymphopenia following CPB and early postoperative infection in children. METHODS: A retrospective analysis including 41 children under 2 years old underwent CPB. Among them, 9 subjects had an early postoperative infection, and 32 subjects were period-matched without infection. Inflammatory cytokines, serum CRP and PCT values were measured in plasma, additionally, circulating total leucocyte and lymphocyte subpopulations were counted. RESULTS: Infected subjects exhibited significantly higher levels of inflammatory cytokines, including IL-6, IL-8, IL-10, IL-1ß and TNF-α, than non-infected subjects after CPB. Additionally, lower absolute number of lymphocyte and their subpopulations CD3+ T cells, CD4+ T-helper cells and CD8+cytotoxic T-cells, were observed in infected subjects. The impairment of T-cells Immune was found to be associated with higher levels of inflammatory cytokines IL-10. The ROC demonstrated that the absolute number of CD3+ T-cells <1934/ul, CD4+ T helper cells <1203/ul and CD8+cytotoxic T-cells <327/ul were associated with early postoperative infection. CONCLUSION: Higher levels of inflammatory cytokines resulted in T-cells lymphopenia after CPB, which significantly increasing the risk of postoperative infection in infants and young children. IMPACT: Infection complications after cardiopulmonary bypass (CPB) in pediatric CHD patients are serious issues, identifing the infection from after CPB remains a challenging. CPB can release numerous inflammatory cytokines associated with T cells lymphopenia, which increases the risk of postoperative infection after surgery. Monitoring T cells lymphopenia maybe more beneficial to predict early postoperative infection than C-reactive protein and procalcitonin.


Asunto(s)
Puente Cardiopulmonar , Linfopenia , Lactante , Humanos , Niño , Preescolar , Puente Cardiopulmonar/efectos adversos , Interleucina-10 , Estudios Retrospectivos , Citocinas , Linfocitos T , Linfopenia/etiología
20.
J Org Chem ; 89(13): 9381-9388, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38885147

RESUMEN

A Pd(II)/N,N'-disulfonyl bisimidazoline-catalyzed asymmetric 1,4-conjugate addition reaction of low-cost arylboronic acids with readily available ß-substituted cyclic enones is described, providing a straightforward way of constructing cyclic all-carbon quaternary stereocenters with high enantioselectivity, in which ≥96% ee was obtained in most cases. The reaction proceeded without the protection of inert gas, making the operation process simple. Theoretical calculations have been applied to understand the origins of enantioselectivity.

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