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1.
Nature ; 587(7833): 313-318, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32698188

RESUMEN

Persistently depolarizing sodium (Na+) leak currents enhance electrical excitability1,2. The ion channel responsible for the major background Na+ conductance in neurons is the Na+ leak channel, non-selective (NALCN)3,4. NALCN-mediated currents regulate neuronal excitability linked to respiration, locomotion and circadian rhythm4-10. NALCN activity is under tight regulation11-14 and mutations in NALCN cause severe neurological disorders and early death15,16. NALCN is an orphan channel in humans, and fundamental aspects of channel assembly, gating, ion selectivity and pharmacology remain obscure. Here we investigate this essential leak channel and determined the structure of NALCN in complex with a distinct auxiliary subunit, family with sequence similarity 155 member A (FAM155A). FAM155A forms an extracellular dome that shields the ion-selectivity filter from neurotoxin attack. The pharmacology of NALCN is further delineated by a walled-off central cavity with occluded lateral pore fenestrations. Unusual voltage-sensor domains with asymmetric linkages to the pore suggest mechanisms by which NALCN activity is modulated. We found a tightly closed pore gate in NALCN where the majority of missense patient mutations cause gain-of-function phenotypes that cluster around the S6 gate and distinctive π-bulges. Our findings provide a framework to further study the physiology of NALCN and a foundation for discovery of treatments for NALCN channelopathies and other electrical disorders.


Asunto(s)
Microscopía por Crioelectrón , Canales Iónicos/química , Canales Iónicos/ultraestructura , Proteínas de la Membrana/química , Proteínas de la Membrana/ultraestructura , Mutación con Ganancia de Función , Células HEK293 , Humanos , Canales Iónicos/genética , Canales Iónicos/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Modelos Moleculares , Mutación Missense , Dominios Proteicos , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo
2.
Cancer ; 130(12): 2169-2179, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38319287

RESUMEN

BACKGROUND: Use of multivitamin supplements has been associated with lower incidence of colorectal cancer (CRC). However, its influence on CRC survival remains unknown. METHODS: Among 2424 patients with stage I-III CRC who provided detailed information about multivitamin supplements in the Nurses' Health Study and Health Professionals Follow-up Study, the authors calculated multivariable hazard ratios (HRs) of multivitamin supplements for all-cause and CRC-specific mortality according to post-diagnostic use and dose of multivitamin supplements. RESULTS: During a median follow-up of 11 years, the authors documented 1512 deaths, among which 343 were of CRC. Compared to non-users, post-diagnostic users of multivitamin supplements at a dose of 3-5 tablets/week had lower CRC-specific mortality (HR, 0.55; 95% confidence interval [CI], 0.36-0.83, p = .005), and post-diagnostic users at doses of 3-5 and 6-9 tablets/week had lower all-cause mortality (HR, 0.81; 95% CI, 0.67-0.99, p = .04; HR, 0.79; 95% CI, 0.70-0.88), p < .001). The dose-response analysis showed a curvilinear relationship for both CRC-specific (pnonlinearity < .001) and all-cause mortality (pnonlinearity = .004), with the maximum risk reduction observed at 3-5 tablets/week and no further reduction at higher doses. Compared to non-users in both pre- and post-diagnosis periods, new post-diagnostic users at dose of <10 tablets/week had a lower all-cause mortality (HR, 0.81; 95% CI, 0.71-0.94, p = .005), whereas new users at a dose of ≥10 tablets/week (HR, 1.58; 95% CI, 1.07-2.33) and discontinued users (HR, 1.35; 95% CI, 1.14-1.59) had a higher risk of mortality. CONCLUSIONS: Use of multivitamin supplements at a moderate dose after a diagnosis of nonmetastatic CRC is associated with lower CRC-specific and overall mortality, whereas a high dose (≥10 tablets/week) use is associated with higher CRC-specific mortality.


Asunto(s)
Neoplasias Colorrectales , Suplementos Dietéticos , Vitaminas , Humanos , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/diagnóstico , Femenino , Vitaminas/administración & dosificación , Estudios Prospectivos , Masculino , Persona de Mediana Edad , Anciano , Adulto , Estudios de Seguimiento , Modelos de Riesgos Proporcionales
3.
Acta Pharmacol Sin ; 45(6): 1189-1200, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38438579

RESUMEN

Maintenance of intestinal barrier function contributes to gastrointestinal homeostasis and therefore cardiovascular diseases. A number of studies show that intestinal permeability is affected by excessive inflammatory responses. Krüppel-like factor (KLF) 4 is one of the critical transcriptional factors, which controls multiple immune responses. In this study we investigated the role of KLF4 in regulating intestinal inflammation and permeability during the atherosclerotic process. Atherosclerotic model was established in ApoE-/- mice by feeding a high fat high cholesterol (HFHC) diet. We showed that colon expression levels of KLF4 and tight junction proteins were significantly decreased whereas inflammatory responses increased in atherosclerotic mice. Overexpression of colon epithelial Klf4 decreased atherosclerotic plaque formation and vascular inflammation in atherosclerotic mice, accompanied by remarkable suppression of intestinal NF-κB activation. We found that overexpression of epithelial Klf4 in atherosclerotic mice significantly increased intestinal tight junction expression and ameliorated endotoxemia, whereas replenishment of LPS abolished these benefits. Overexpression of Klf4 reversed LPS-induced permeability and downregulation of ZO-1 and Occludin in Caco-2 cells in vitro. HFHC diet stimulated the expression of epithelial microRNA-34a, whereas silence of epithelial Klf4 abolished the benefits of microRNA-34a sponge, a specific miR-34a inhibitor, on intestinal permeability and atherosclerotic development. A clinical cohort of 24 atherosclerotic patients supported colon KLF4/NF-κB/tight junction protein axis mediated intestine/cardiovascular interaction in patients with atherosclerosis. Taken together, intestinal epithelial KLF4 protects against intestinal inflammation and barrier dysfunction, ameliorating atherosclerotic plaque formation.


Asunto(s)
Aterosclerosis , Endotoxemia , Mucosa Intestinal , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel , Ratones Endogámicos C57BL , MicroARNs , FN-kappa B , Factor 4 Similar a Kruppel/metabolismo , Animales , Aterosclerosis/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , FN-kappa B/metabolismo , MicroARNs/metabolismo , MicroARNs/genética , Humanos , Endotoxemia/metabolismo , Ratones , Mucosa Intestinal/metabolismo , Masculino , Células CACO-2 , Permeabilidad , Lipopolisacáridos , Funcion de la Barrera Intestinal
4.
Am J Respir Crit Care Med ; 207(2): 173-182, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-35943859

RESUMEN

Rationale: The individual effects of early-life tobacco smoke exposure and its interactions with genetic factors on lung cancer in adulthood remain unclear. Objectives: To investigate the associations of early-life tobacco exposures as well as their interactions with polygenic risk scores (PRSs) with lung cancer incidence and mortality. Methods: A total of 432,831 participants from the UK Biobank study were included. We estimated the associations of in utero exposure to tobacco smoke, the age of smoking initiation and their interactions with PRSs with lung cancer incidence and mortality in adulthood using Cox proportional hazard models. Measurements and Main Results: Lung cancer incidence (hazard ratio [HR]: 1.59, 95% confidence interval [CI], 1.44-1.76) increased among participants with in utero tobacco exposure. Multivariable-adjusted HRs (with 95% CIs) of lung cancer incidence for smoking initiation in adulthood, adolescence, and childhood (versus never-smokers) were 6.10 (5.25-7.09), 9.56 (8.31-11.00), and 15.15 (12.90-17.79) (Ptrend < 0.001). Similar findings were observed in lung cancer mortality. Participants with high PRSs and in utero tobacco exposure (versus low PRSs participants without in utero exposure) had an HR of 2.35 for lung cancer incidence (95% CI, 1.97-2.80, Pinteraction = 0.089) and 2.43 for mortality (95% CI, 2.05-2.88, Pinteraction = 0.032). High PRSs with smoking initiation in childhood (versus never-smokers with low PRSs) had HRs of 18.71 for incidence (95% CI, 14.21-24.63, Pinteraction = 0.004) and 19.74 for mortality (95% CI, 14.98-26.01, Pinteraction = 0.033). Conclusions: In utero and childhood/adolescence exposure to tobacco smoke and its interaction with genetic factors may substantially increase the risks of lung cancer incidence and mortality in adulthood.


Asunto(s)
Neoplasias Pulmonares , Contaminación por Humo de Tabaco , Humanos , Adolescente , Contaminación por Humo de Tabaco/efectos adversos , Incidencia , Nicotiana , Factores de Riesgo , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/genética
5.
Nucleic Acids Res ; 50(D1): D46-D53, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34551433

RESUMEN

Enhancer RNAs (eRNAs) are a class of non-coding RNAs transcribed from enhancers. As the markers of active enhancers, eRNAs play important roles in gene regulation and are associated with various complex traits and characteristics. With increasing attention to eRNAs, numerous eRNAs have been identified in different human tissues. However, the expression landscape, regulatory network and potential functions of eRNAs in animals have not been fully elucidated. Here, we systematically characterized 185 177 eRNAs from 5085 samples across 10 species by mapping the RNA sequencing data to the regions of known enhancers. To explore their potential functions based on evolutionary conservation, we investigated the sequence similarity of eRNAs among multiple species. In addition, we identified the possible associations between eRNAs and transcription factors (TFs) or nearby genes to decipher their possible regulators and target genes, as well as characterized trait-related eRNAs to explore their potential functions in biological processes. Based on these findings, we further developed Animal-eRNAdb (http://gong_lab.hzau.edu.cn/Animal-eRNAdb/), a user-friendly database for data searching, browsing and downloading. With the comprehensive characterization of eRNAs in various tissues of different species, Animal-eRNAdb may greatly facilitate the exploration of functions and mechanisms of eRNAs.


Asunto(s)
Bases de Datos Genéticas , Elementos de Facilitación Genéticos/genética , ARN/genética , Programas Informáticos , Animales , Biología Computacional , Regulación de la Expresión Génica/genética , Regiones Promotoras Genéticas/genética , Transcripción Genética
6.
Int J Cancer ; 153(2): 278-289, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-36946647

RESUMEN

Serum 25-hydroxyvitamin D (25(OH)D) has been demonstrated to be associated with risk of colorectal cancer (CRC). However, it remains unclear whether this association was modified by vitamin D-related polymorphisms. We evaluated association of serum 25(OH)D concentration with CRC risk among 403 170 participants from UK Biobank Project. Two variants of vitamin D binding protein (VDBP), rs4588 and rs7041, were included to estimate the binding affinity of 25(OH)D to VDBP, and three variants of vitamin D receptor (VDR), rs11568820, rs2228570 and rs1544410, which may influence VDR activity, were also investigated. Multivariable Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During 4 957 677 person-years of follow-up, 5053 incident CRC cases were documented. Higher serum 25(OH)D concentrations were significantly associated with lower CRC incidence in a dose-response manner, with HR (95% CIs) being 0.94 (0.91-0.97) per 1 SD increment of serum 25(OH)D level (Ptrend < .001). When separated by anatomic site, we observed a significant association between higher 25(OH)D and lower incidence of colon cancer (Ptrend < .001), but not rectal cancer (Ptrend = .880). The inverse associations between 25(OH)D level and CRC risk were demonstrated in almost all individuals carrying different GC or VDR genotypes, except for those with rs1544410 TT or rs4588 TT genotypes. There was no significant interaction between any single variant, or haplotypes of GC or VDR, and 25(OH)D level. Our findings suggest the potential benefits of maintaining adequate vitamin D for CRC prevention, particularly for tumors from colon.


Asunto(s)
Neoplasias Colorrectales , Polimorfismo de Nucleótido Simple , Humanos , Vitamina D , Vitaminas , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Genotipo , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Proteína de Unión a Vitamina D/genética
7.
Lancet ; 400(10346): 116-125, 2022 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-35810757

RESUMEN

BACKGROUND: The benefit of combined treatment with intravenous thrombolysis before endovascular thrombectomy in patients with acute ischaemic stroke caused by large vessel occlusion remains unclear. We hypothesised that the clinical outcomes of patients with stroke with large vessel occlusion treated with direct endovascular thrombectomy within 4·5 h would be non-inferior compared with the outcomes of those treated with standard bridging therapy (intravenous thrombolysis before endovascular thrombectomy). METHODS: DIRECT-SAFE was an international, multicentre, prospective, randomised, open-label, blinded-endpoint trial. Adult patients with stroke and large vessel occlusion in the intracranial internal carotid artery, middle cerebral artery (M1 or M2), or basilar artery, confirmed by non-contrast CT and vascular imaging, and who presented within 4·5 h of stroke onset were recruited from 25 acute-care hospitals in Australia, New Zealand, China, and Vietnam. Eligible patients were randomly assigned (1:1) via a web-based, computer-generated randomisation procedure stratified by site of baseline arterial occlusion and by geographic region to direct endovascular thrombectomy or bridging therapy. Patients assigned to bridging therapy received intravenous thrombolytic (alteplase or tenecteplase) as per standard care at each site; endovascular thrombectomy was also per standard of care, using the Trevo device (Stryker Neurovascular, Fremont, CA, USA) as first-line intervention. Personnel assessing outcomes were masked to group allocation; patients and treating physicians were not. The primary efficacy endpoint was functional independence defined as modified Rankin Scale score 0-2 or return to baseline at 90 days, with a non-inferiority margin of -0·1, analysed by intention to treat (including all randomly assigned and consenting patients) and per protocol. The intention-to-treat population was included in the safety analyses. The trial is registered with ClinicalTrials.gov, NCT03494920, and is closed to new participants. FINDINGS: Between June 2, 2018, and July 8, 2021, 295 patients were randomly assigned to direct endovascular thrombectomy (n=148) or bridging therapy (n=147). Functional independence occurred in 80 (55%) of 146 patients in the direct thrombectomy group and 89 (61%) of 147 patients in the bridging therapy group (intention-to-treat risk difference -0·051, two-sided 95% CI -0·160 to 0·059; per-protocol risk difference -0·062, two-sided 95% CI -0·173 to 0·049). Safety outcomes were similar between groups, with symptomatic intracerebral haemorrhage occurring in two (1%) of 146 patients in the direct group and one (1%) of 147 patients in the bridging group (adjusted odds ratio 1·70, 95% CI 0·22-13·04) and death in 22 (15%) of 146 patients in the direct group and 24 (16%) of 147 patients in the bridging group (adjusted odds ratio 0·92, 95% CI 0·46-1·84). INTERPRETATION: We did not show non-inferiority of direct endovascular thrombectomy compared with bridging therapy. The additional information from our study should inform guidelines to recommend bridging therapy as standard treatment. FUNDING: Australian National Health and Medical Research Council and Stryker USA.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Adulto , Australia , Isquemia Encefálica/tratamiento farmacológico , Procedimientos Endovasculares/métodos , Fibrinolíticos/efectos adversos , Humanos , Estudios Prospectivos , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Resultado del Tratamiento
8.
Gastroenterology ; 163(4): 862-874, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35760086

RESUMEN

BACKGROUND & AIMS: Evidence supports a carcinogenic role of Escherichia coli carrying the pks island that encodes enzymes for colibactin biosynthesis. We hypothesized that the association of the Western-style diet (rich in red and processed meat) with colorectal cancer incidence might be stronger for tumors containing higher amounts of pks+E coli. METHODS: Western diet score was calculated using food frequency questionnaire data obtained every 4 years during follow-up of 134,775 participants in 2 United States-wide prospective cohort studies. Using quantitative polymerase chain reaction, we measured pks+E coli DNA in 1175 tumors among 3200 incident colorectal cancer cases that had occurred during the follow-up. We used the 3200 cases and inverse probability weighting (to adjust for selection bias due to tissue availability), integrated in multivariable-adjusted duplication-method Cox proportional hazards regression analyses. RESULTS: The association of the Western diet score with colorectal cancer incidence was stronger for tumors containing higher levels of pks+E coli (Pheterogeneity = .014). Multivariable-adjusted hazard ratios (with 95% confidence interval) for the highest (vs lowest) tertile of the Western diet score were 3.45 (1.53-7.78) (Ptrend = 0.001) for pks+E coli-high tumors, 1.22 (0.57-2.63) for pks+E coli-low tumors, and 1.10 (0.85-1.42) for pks+E coli-negative tumors. The pks+E coli level was associated with lower disease stage but not with tumor location, microsatellite instability, or BRAF, KRAS, or PIK3CA mutations. CONCLUSIONS: The Western-style diet is associated with a higher incidence of colorectal cancer containing abundant pks+E coli, supporting a potential link between diet, the intestinal microbiota, and colorectal carcinogenesis.


Asunto(s)
Neoplasias Colorrectales , Infecciones por Escherichia coli , Carcinogénesis , Fosfatidilinositol 3-Quinasa Clase I , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Dieta Occidental , Escherichia coli/genética , Humanos , Estudios Prospectivos , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)
9.
Arch Toxicol ; 97(7): 2015-2028, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37245169

RESUMEN

Although genome-wide association studies (GWASs) have identified over 100 colorectal cancer (CRC) risk loci, an understanding of causal genes or risk variants and their biological functions in these loci remain unclear. Recently, genomic loci 10q26.12 with lead SNP rs1665650 was identified as an essential CRC risk loci of Asian populations. However, the functional mechanism of this region has not been fully clarified. Here, we applied an RNA interfering-based on-chip approach to screen for the genes essential for cell proliferation in the CRC risk loci 10q26.12. Notably, HSPA12A had the most significant effect among the identified genes and functioned as a crucial oncogene facilitating cell proliferation. Moreover, we conducted an integrative fine-mapping analysis to identify putative casual variants and further explored their association with CRC risk in a large-scale Chinese population consisting of 4054 cases and 4054 controls and also independently validated in 5208 cases and 20,832 controls from the UK biobank cohort. We identified a risk SNP rs7093835 in the intron of HSPA12A that was significantly associated with an increased risk of CRC (OR 1.23, 95% CI 1.08-1.41, P = 1.92 × 10-3). Mechanistically, the risk variant could facilitate an enhancer-promoter interaction mediated by the transcriptional factor (TF) GRHL1 and ultimately upregulate HSPA12A expression, which provides functional evidence to support our population findings. Collectively, our study reveals the important role of HSPA12A in CRC development and illustrates a novel enhancer-promoter interaction module between HSPA12A and its regulatory elements rs7093835, providing new insights into the etiology of CRC.


Asunto(s)
Neoplasias Colorrectales , Estudio de Asociación del Genoma Completo , Humanos , Predisposición Genética a la Enfermedad , Regiones Promotoras Genéticas , Riesgo , Neoplasias Colorrectales/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Proteínas HSP70 de Choque Térmico/genética
10.
Nucleic Acids Res ; 49(D1): D1065-D1073, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33010176

RESUMEN

Tumor-infiltrating immune cells as integral component of the tumor microenvironment are associated with tumor progress, prognosis and responses to immunotherapy. Genetic variants have been demonstrated to impact tumor-infiltrating, underscoring the heritable character of immune landscape. Therefore, identification of immunity quantitative trait loci (immunQTLs), which evaluate the effect of genetic variants on immune cells infiltration, might present a critical step toward fully understanding the contribution of genetic variants in tumor development. Although emerging studies have demonstrated the determinants of germline variants on immune infiltration, no database has yet been developed to systematically analyze immunQTLs across multiple cancer types. Using genotype data from TCGA database and immune cell fractions estimated by CIBERSORT, we developed a computational pipeline to identify immunQTLs in 33 cancer types. A total of 913 immunQTLs across different cancer types were identified. Among them, 5 immunQTLs are associated with patient overall survival. Furthermore, by integrating immunQTLs with GWAS data, we identified 527 immunQTLs overlapping with known GWAS linkage disequilibrium regions. Finally, we constructed a user-friendly database, CancerImmunityQTL (http://www.cancerimmunityqtl-hust.com/) for users to browse, search and download data of interest. This database provides an informative resource to understand the germline determinants of immune infiltration in human cancer and benefit from personalized cancer immunotherapy.


Asunto(s)
Bases de Datos Genéticas , Inmunidad/genética , Neoplasias/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo/genética , Microambiente Tumoral/genética , Minería de Datos/métodos , Regulación Neoplásica de la Expresión Génica , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Internet , Desequilibrio de Ligamiento , Neoplasias/inmunología , Pronóstico , Sitios de Carácter Cuantitativo/inmunología , Microambiente Tumoral/inmunología , Interfaz Usuario-Computador
11.
Chaos ; 33(12)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38079648

RESUMEN

This paper proposes an adaptive integral alternating minimization method (AIAMM) for learning nonlinear dynamical systems using highly corrupted measured data. This approach selects and identifies the system directly from noisy data using the integral model, encompassing unknown sparse coefficients, initial values, and outlier noisy data within the learning problem. It is defined as a sparse robust linear regression problem. An adaptive threshold parameter selection method is proposed to constrain model fitting errors and select appropriate threshold parameters for sparsity. The robustness and accuracy of the proposed AIAMM are demonstrated through several numerical experiments on typical nonlinear dynamical systems, including the van der Pol oscillator, Mathieu oscillator, Lorenz system, and 5D self-exciting homopolar disc dynamo. The proposed method is also compared to several advanced methods for sparse recovery, with the results indicating that the AIAMM demonstrates superior performance in processing highly corrupted data.

12.
Angew Chem Int Ed Engl ; 62(23): e202300704, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36988016

RESUMEN

Despite the widespread success in the functionalization of C(sp2 )-H bonds, the deliberate functionalization of C(sp3 )-H bonds in a highly site- and stereoselective manner remains a longstanding challenge. Herein, we report an iridium/aluminum cooperative catalytic system that enables the ß-selective C-H borylation of saturated cyclic amines and lactams. Furthermore, we have accomplished an enantioselective variant using binaphthol-derived chiral aluminum catalysts to forge C-B bonds with high levels of stereocontrol. Computational studies suggest that the formation of a Lewis pair with the substrates is crucial to lower the energy of the transition state for the rate-determining reductive elimination step.

13.
J Am Chem Soc ; 144(32): 14864-14873, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35921609

RESUMEN

Biaryl phosphines bearing C(Ar)-C(Ar) axial chirality are commonly known and have been successfully applied in many asymmetric catalyses. Nevertheless, the development of a chiral ligand having an axially chiral C(Ar)-N backbone remains elusive due to its undesirable less restricted rotational barrier. In fact, it is highly attractive to overcome this challenge in ligand development as the incorporation of an N-donor component at the chiral axis is more favorable toward the transient metal coordination, and thus, a better outcome of stereocommunication is anticipated to the approaching substrates. Herein, we present a rational design of a new collection of chiral phosphines featuring a C-N axial chirality and their applications in enantioselective Suzuki-Miyaura cross-coupling for accessing highly steric hindered tetra-ortho-substituted biaryls (26 examples up to 98:2 er). It is worth noting that the embodied carbazolyl framework is crucial to succeed the reaction, by the fruitful steric relief of bulky substrate coordination and transmetalation via a fleeting Pd-N jumping to Pd-π fashion. DFT calculation reveals an interesting Pd-arene-walking characteristic across the carbazolyl plane for attaining a lower energy-preferred route in a catalytic cycle. The theoretical study successfully predicts the stereooutcome and matches the enantioselectivity with the experimental results.


Asunto(s)
Fosfinas , Catálisis , Ligandos , Estereoisomerismo
14.
Int J Cancer ; 151(9): 1523-1534, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35716133

RESUMEN

It remains unknown whether maintenance of a healthy lifestyle after endoscopic polypectomy could still confer benefit for colorectal cancer (CRC) incidence and mortality. In this study, we defined a healthy lifestyle score based on body mass index, smoking, physical activity, alcohol consumption and diet (range, 0-5). We used Cox proportional hazards regression to estimate the hazard ratios (HRs) for the associations of healthy lifestyle score and individual lifestyle factors with CRC incidence and all-cause mortality. During a median of 10 years of follow-up of 24 668 participants who underwent endoscopic polypectomy, we documented 161 CRC cases and 4857 all-cause deaths. A higher healthy lifestyle score after endoscopic polypectomy was associated with lower risk of CRC and all-cause mortality. Compared with individuals with 0 to 1 healthy lifestyle factors, those with 2, 3 and 4 to 5 healthy lifestyle factors had a HR for CRC risk of 0.86 (95% confidence interval [CI], 0.60-1.24), 0.73 (95% CI, 0.47-1.14) and 0.52 (95% CI, 0.27-1.01), respectively (Ptrend  = .03). The corresponding HR (95% CI) for all-cause mortality was 0.83 (95% CI, 0.76-0.90), 0.63 (95% CI, 0.56-0.70) and 0.56 (95% CI, 0.48-0.65), respectively (Ptrend < .0001). In the joint analysis of pre- and postpolypectomy periods, patients with a healthy postpolypectomy lifestyle had a lower incidence of CRC regardless of their prepolypectomy exposure, whereas those with a healthy lifestyle in both periods had a lower mortality than those with an unhealthy lifestyle in either period. In conclusion, adherence to a healthy lifestyle after polypectomy may confer significant benefit for CRC prevention and reduction in all-cause mortality.


Asunto(s)
Neoplasias Colorrectales , Estilo de Vida Saludable , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/prevención & control , Neoplasias Colorrectales/cirugía , Humanos , Incidencia , Estilo de Vida , Estudios Prospectivos , Factores de Riesgo
15.
Am J Hum Genet ; 105(1): 29-47, 2019 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-31204011

RESUMEN

Genome-wide association studies (GWASs) have identified approximately 100 colorectal cancer (CRC) risk loci. However, the causal genes in these loci have not been systematically interrogated. We conducted a high-throughput RNA-interference functional screen to identify the genes essential for proliferation in the CRC risk loci of Asian populations. We found that ATF1, located in the 12q13.12 region, functions as an oncogene that facilitates cell proliferation; ATF1 has the most significant effect of the identified genes and promotes CRC xenograft growth by affecting cell apoptosis. Next, by integrating a fine-mapping analysis, a two-stage affected-control study consisting of 6,213 affected individuals and 10,388 controls, and multipronged experiments, we elucidated that two risk variants, dbSNP: rs61926301 and dbSNP: rs7959129, that located in the ATF1 promoter and first intron, respectively, facilitate a promoter-enhancer interaction, mediated by the synergy of SP1 and GATA3, to upregulate ATF1 expression, thus synergistically predisposing to CRC risk (OR = 1.77, 95% CI = 1.42-2.21, p = 3.16 × 10-7; Pmultiplicative-interaction = 1.20 × 10-22; Padditive-interaction = 6.50 × 10-3). Finally, we performed RNA-seq and ChIP-seq assays in CRC cells treated with ATF1 overexpression in order to dissect the target programs of ATF1. Results showed that ATF1 activates a subset of genes, including BRAF, NRAS, MYC, BIRC2, DAAM1, MAML2, STAT1, ID1, and NKD2, related to apoptosis, Wnt, TGF-ß, and MAPK pathways, and these effects could cooperatively increase the risk of CRC. These findings reveal the clinical potential of ATF1 in CRC development and illuminate a promoter-enhancer interaction module between the ATF1 regulatory elements dbSNP: rs61926301 and dbSNP: rs7959129, and they bring us closer to understanding the molecular drivers of cancer.


Asunto(s)
Factor de Transcripción Activador 1/metabolismo , Neoplasias Colorrectales/patología , Elementos de Facilitación Genéticos , Regulación Neoplásica de la Expresión Génica , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Factor de Transcripción Activador 1/antagonistas & inhibidores , Factor de Transcripción Activador 1/genética , Animales , Apoptosis , Sistemas CRISPR-Cas , Estudios de Casos y Controles , Proliferación Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Femenino , Edición Génica , Predisposición Genética a la Enfermedad , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Sitios de Carácter Cuantitativo , Interferencia de ARN , Factores de Riesgo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Cancer Immunol Immunother ; 71(4): 933-942, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34529108

RESUMEN

BACKGROUND: Despite heightened interest in early-onset colorectal cancer (CRC) diagnosed before age 50, little is known on immune cell profiles of early-onset CRC. It also remains to be studied whether CRCs diagnosed at or shortly after age 50 are similar to early-onset CRC. We therefore hypothesized that immune cell infiltrates in CRC tissue might show differential heterogeneity patterns between three age groups (< 50 "early onset," 50-54 "intermediate onset," ≥ 55 "later onset"). METHODS: We examined 1,518 incident CRC cases with available tissue data, including 35 early-onset and 73 intermediate-onset cases. To identify immune cells in tumor intraepithelial and stromal areas, we developed three multiplexed immunofluorescence assays combined with digital image analyses and machine learning algorithms, with the following markers: (1) CD3, CD4, CD8, CD45RO (PTPRC), and FOXP3 for T cells; (2) CD68, CD86, IRF5, MAF, and MRC1 (CD206) for macrophages; and (3) ARG1, CD14, CD15, CD33, and HLA-DR for myeloid cells. RESULTS: Although no comparisons between age groups showed statistically significant differences at the stringent two-sided α level of 0.005, compared to later-onset CRC, early-onset CRC tended to show lower levels of tumor-infiltrating lymphocytes (P = 0.013), intratumoral periglandular reaction (P = 0.025), and peritumoral lymphocytic reaction (P = 0.044). Compared to later-onset CRC, intermediate-onset CRC tended to show lower densities of overall macrophages (P = 0.050), M1-like macrophages (P = 0.062), CD14+HLA-DR+ cells (P = 0.015), and CD3+CD4+FOXP3+ cells (P = 0.039). CONCLUSIONS: This hypothesis-generating study suggests possible differences in histopathologic lymphocytic reaction patterns, macrophages, and regulatory T cells in the tumor microenvironment by age at diagnosis.


Asunto(s)
Neoplasias Colorrectales , Microambiente Tumoral , Neoplasias Colorrectales/patología , Antígenos HLA-DR , Humanos , Linfocitos Infiltrantes de Tumor , Macrófagos , Persona de Mediana Edad
17.
BMC Plant Biol ; 22(1): 217, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35477360

RESUMEN

BACKGROUND: Magnesium ion is one of the essential mineral elements for plant growth and development, which participates in a variety of physiological and biochemical processes. Since there is no report on the research of magnesium ion transporter in grape, the study of the structure and function of magnesium ion transporters (MGT) is helpful to understand the dynamic balance mechanism of intracellular magnesium ions and their inter- or intra-cellular activities. RESULT: In this study, we identified the members of MGT protein family in grape and performed the phylogenetic and expression analysis. We have identified nine VvMGT genes in grape genome, which are distributed on eight different chromosomes. Phylogenetic analysis showed that MGT family members of grapes were divided into five subfamilies and had obvious homology with Arabidopsis, maize, and pear. Based on transcriptome data from the web databases, we analyzed the expression patterns of VvMGTs at different development stages and in response to abiotic stresses including waterlogging, drought, salinity, and copper. Using qRT-PCR method, we tested the expression of grape VvMGTs under magnesium and aluminum treatments and found significant changes in VvMGTs expression. In addition, four of the MGT proteins in grape were located in the nucleus. CONCLUSION: Overall, in this study we investigated the structural characteristics, evolution pattern, and expression analysis of VvMGTs in depth, which laid the foundation for further revealing the function of VvMGT genes in grape.


Asunto(s)
Arabidopsis , Vitis , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Magnesio/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Vitis/metabolismo
18.
Genet Med ; 24(2): 319-331, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34906466

RESUMEN

PURPOSE: Adducins interconnect spectrin and actin filaments to form polygonal scaffolds beneath the cell membranes and form ring-like structures in neuronal axons. Adducins regulate mouse neural development, but their function in the human brain is unknown. METHODS: We used exome sequencing to uncover ADD1 variants associated with intellectual disability (ID) and brain malformations. We studied ADD1 splice isoforms in mouse and human neocortex development with RNA sequencing, super resolution imaging, and immunoblotting. We investigated 4 variant ADD1 proteins and heterozygous ADD1 cells for protein expression and ADD1-ADD2 dimerization. We studied Add1 functions in vivo using Add1 knockout mice. RESULTS: We uncovered loss-of-function ADD1 variants in 4 unrelated individuals affected by ID and/or structural brain defects. Three additional de novo copy number variations covering the ADD1 locus were associated with ID and brain malformations. ADD1 is highly expressed in the neocortex and the corpus callosum, whereas ADD1 splice isoforms are dynamically expressed between cortical progenitors and postmitotic neurons. Human variants impair ADD1 protein expression and/or dimerization with ADD2. Add1 knockout mice recapitulate corpus callosum dysgenesis and ventriculomegaly phenotypes. CONCLUSION: Our human and mouse genetics results indicate that pathogenic ADD1 variants cause corpus callosum dysgenesis, ventriculomegaly, and/or ID.


Asunto(s)
Hidrocefalia , Discapacidad Intelectual , Agenesia del Cuerpo Calloso/genética , Agenesia del Cuerpo Calloso/patología , Animales , Variaciones en el Número de Copia de ADN , Humanos , Hidrocefalia/genética , Discapacidad Intelectual/genética , Ratones , Fenotipo
19.
J Org Chem ; 87(23): 16039-16046, 2022 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-36379013

RESUMEN

Pd-catalyzed borylation of fluorobenzene was theoretically studied. DFT calculations revealed that the reaction occurs through an unprecedented 3 + 6-membered ring transition state, in which one LiHMDS (HMDS = hexamethyldisilazane) acts as a ligand and another LiHMDS is essential to provide Li···N and Li···F interactions, overcoming the large destabilization of the strong phenyl-F bond distortion. The characteristic feature of LiHMDS was elucidated by comparing it with HMDS and NaHMDS analogues.


Asunto(s)
Fluorobencenos , Paladio , Paladio/química , Modelos Moleculares , Ligandos
20.
Am J Emerg Med ; 54: 287-296, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35227959

RESUMEN

BACKGROUND: The use of vasopressors is vital in septic shock. However, the optimal timing of treatment remains unclear. Therefore, we aimed to explore the impact of early norepinephrine initiation on the survival of patients with septic shock. METHODS: We selected 4253 patients from the Medical Information Mart for Intensive Care IV database between 2008 and 2019. The primary outcome was 28-day mortality. Propensity score matching (PSM) was applied to minimize between-group imbalances, and a restricted mean survival time was used to quantify the beneficial impact of early norepinephrine treatment on survival. Sensitivity analyses were conducted to test the robustness of the study results in multiple cohorts. RESULTS: In the PSM cohort, 2862 patients were equally assigned to early (receiving norepinephrine within the first 3 h) and delayed (> 3 h) norepinephrine initiation groups. Patients in the early norepinephrine initiation group received significantly less fluid therapy (0 vs. 79 mL/kg), had lower 28-day mortality (30.0% vs. 37.8%), longer survival days (21.89 vs. 20.37 days), shorter duration of intensive care unit (4.9 vs. 7.2 days) and hospital stays (12.4 vs. 13.6 days), shorter duration of supportive norepinephrine and invasive mechanical ventilation, lower incidence of organ failure progression (64.4% vs. 79.2%) within 24 h after shock onset, and higher mean arterial pressure within 6 and 24 h after shock onset than patients in the delayed norepinephrine initiation group (p < 0.05). CONCLUSIONS: Norepinephrine initiation within the first 3 h, regardless of preload dependency, was associated with longer survival time and shorter duration of supportive norepinephrine and invasive mechanical ventilation and may delay or partially reverse rapid onset organ failure.


Asunto(s)
Norepinefrina , Choque Séptico , Fluidoterapia , Humanos , Unidades de Cuidados Intensivos , Norepinefrina/uso terapéutico , Puntaje de Propensión , Choque Séptico/tratamiento farmacológico , Vasoconstrictores/uso terapéutico
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