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1.
Circulation ; 149(4): 317-329, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-37965733

RESUMEN

BACKGROUND: Pathogenic variants in SCN5A can result in long QT syndrome type 3, a life-threatening genetic disease. Adenine base editors can convert targeted A T base pairs to G C base pairs, offering a promising tool to correct pathogenic variants. METHODS: We generated a long QT syndrome type 3 mouse model by introducing the T1307M pathogenic variant into the Scn5a gene. The adenine base editor was split into 2 smaller parts and delivered into the heart by adeno-associated virus serotype 9 (AAV9-ABEmax) to correct the T1307M pathogenic variant. RESULTS: Both homozygous and heterozygous T1307M mice showed significant QT prolongation. Carbachol administration induced Torsades de Pointes or ventricular tachycardia for homozygous T1307M mice (20%) but not for heterozygous or wild-type mice. A single intraperitoneal injection of AAV9-ABEmax at postnatal day 14 resulted in up to 99.20% Scn5a transcripts corrected in T1307M mice. Scn5a mRNA correction rate >60% eliminated QT prolongation; Scn5a mRNA correction rate <60% alleviated QT prolongation. Partial Scn5a correction resulted in cardiomyocytes heterogeneity, which did not induce severe arrhythmias. We did not detect off-target DNA or RNA editing events in ABEmax-treated mouse hearts. CONCLUSIONS: These findings show that in vivo AAV9-ABEmax editing can correct the variant Scn5a allele, effectively ameliorating arrhythmia phenotypes. Our results offer a proof of concept for the treatment of hereditary arrhythmias.


Asunto(s)
Trastorno del Sistema de Conducción Cardíaco , Edición Génica , Síndrome de QT Prolongado , Ratones , Animales , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/terapia , Síndrome de QT Prolongado/diagnóstico , Arritmias Cardíacas , Miocitos Cardíacos , Adenina , ARN Mensajero , Canal de Sodio Activado por Voltaje NAV1.5/genética , Mutación
2.
Nano Lett ; 24(43): 13708-13717, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39417607

RESUMEN

Reactive oxygen species (ROS)-responsive drug delivery systems possess immense potential for targeted delivery and controlled release of therapeutics. However, the rapid responsiveness to ROS and sustained release of antibacterial drugs are often limited by the challenging microenvironment of periodontitis. Integrating ROS-responsive drug delivery systems with photocatalytic technologies presents a strategic approach to overcome these limitations. Herein, a pillararene-embedded covalent organic framework (PCOF) incorporating the antibacterial prodrug thioacetal (TA) has been developed to treat periodontitis. This drug-loaded nanoplatform, namely TA-loaded PCOF, utilizes the self-amplifying ROS property to enhance therapeutic efficacy. PCOFs demonstrate exceptional photosensitivity and ROS generation capabilities when employed as drug carriers. When exposed to ROS, TA within the nanoplatform was activated and cleaved into cinnamaldehyde (CA), a highly potent antibacterial compound. By leveraging visible light to activate the site-specific infection targeting, TA-loaded PCOF effectively alleviated periodontitis, thereby advancing the field of antibacterial drug delivery systems.


Asunto(s)
Antibacterianos , Periodontitis , Fotoquimioterapia , Especies Reactivas de Oxígeno , Periodontitis/tratamiento farmacológico , Periodontitis/microbiología , Fotoquimioterapia/métodos , Especies Reactivas de Oxígeno/metabolismo , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/uso terapéutico , Animales , Sistemas de Liberación de Medicamentos , Portadores de Fármacos/química , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Humanos , Profármacos/química , Profármacos/farmacología , Profármacos/uso terapéutico , Ratones , Acroleína/análogos & derivados
3.
Cancer Immunol Immunother ; 73(3): 58, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38386050

RESUMEN

B cells possess anti-tumor functions mediated by granzyme B, in addition to their role in antigen presentation and antibody production. However, the variations in granzyme B+ B cells between tumor and non-tumor tissues have been largely unexplored. Therefore, we integrated 25 samples from the Gene Expression Omnibus database and analyzed the tumor immune microenvironment. The findings uncovered significant inter- and intra-tumoral heterogeneity. Notably, single-cell data showed higher proportions of granzyme B+ B cells in tumor samples compared to control samples, and these levels were positively associated with disease-free survival. The elevated levels of granzyme B+ B cells in tumor samples resulted from tumor cell chemotaxis through the MIF- (CD74 + CXCR4) signaling pathway. Furthermore, the anti-tumor function of granzyme B+ B cells in tumor samples was adversely affected, potentially providing an explanation for tumor progression. These findings regarding granzyme B+ B cells were further validated in an independent clinic cohort of 40 liver transplant recipients with intrahepatic cholangiocarcinoma. Our study unveils an interaction between granzyme B+ B cells and intrahepatic cholangiocarcinoma, opening up potential avenues for the development of novel therapeutic strategies against this disease.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Trasplante de Hígado , Humanos , Granzimas/genética , Colangiocarcinoma/genética , Colangiocarcinoma/cirugía , Pronóstico , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos , Microambiente Tumoral
4.
J Transl Med ; 22(1): 883, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39354613

RESUMEN

Single-cell technology depicts integrated tumor profiles including both tumor cells and tumor microenvironments, which theoretically enables more robust diagnosis than traditional diagnostic standards based on only pathology. However, the inherent challenges of single-cell RNA sequencing (scRNA-seq) data, such as high dimensionality, low signal-to-noise ratio (SNR), sparse and non-Euclidean nature, pose significant obstacles for traditional diagnostic approaches. The diagnostic value of single-cell technology has been largely unexplored despite the potential advantages. Here, we present a graph neural network-based framework tailored for molecular diagnosis of primary liver tumors using scRNA-seq data. Our approach capitalizes on the biological plausibility inherent in the intercellular communication networks within tumor samples. By integrating pathway activation features within cell clusters and modeling unidirectional inter-cellular communication, we achieve robust discrimination between malignant tumors (including hepatocellular carcinoma, HCC, and intrahepatic cholangiocarcinoma, iCCA) and benign tumors (focal nodular hyperplasia, FNH) by scRNA data of all tissue cells and immunocytes only. The efficacy to distinguish iCCA from HCC was further validated on public datasets. Through extending the application of high-throughput scRNA-seq data into diagnosis approaches focusing on integrated tumor microenvironment profiles rather than a few tumor markers, this framework also sheds light on minimal-invasive diagnostic methods based on migrating/circulating immunocytes.


Asunto(s)
Neoplasias Hepáticas , Redes Neurales de la Computación , Análisis de la Célula Individual , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Análisis de la Célula Individual/métodos , ARN/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Análisis de Secuencia de ARN
5.
Prehosp Emerg Care ; : 1-9, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38739864

RESUMEN

INTRODUCTION: Evidence suggests that Extracorporeal Cardiopulmonary Resuscitation (ECPR) can improve survival rates for nontraumatic out-of-hospital cardiac arrest (OHCA). However, when ECPR is indicated over 50% of potential candidates are unable to qualify in the current hospital-based system due to geographic limitations. This study employs a Geographic Information System (GIS) model to estimate the number of ECPR eligible patients within the United States in the current hospital-based system, a prehospital ECPR ground-based system, and a prehospital ECPR Helicopter Emergency Medical Services (HEMS)-based system. METHODS: We constructed a GIS model to estimate ground and helicopter transport times. Time-dependent rates of ECPR eligibility were derived from the Resuscitation Outcome Consortium (ROC) database, while the Cardiac Arrest Registry to Enhance Survival (CARES) registry determined the number of OHCA patients meeting ECPR criteria within designated transportation times. Emergency Medical Services (EMS) response time, ECPR candidacy determination time, and on-scene time were modeled based on data from the EROCA trial. The combined model was used to estimate the total ECPR eligibility in each system. RESULTS: The CARES registry recorded 736,066 OHCA patients from 2013 to 2021. After applying clinical criteria, 24,661 (3.4%) ECPR-indicated OHCA were identified. When considering overall ECPR eligibility within 45 min from OHCA to initiation, only 11.76% of OHCA where ECPR was indicated were eligible in the current hospital-based system. The prehospital ECPR HEMS-based system exhibited a four-fold increase in ECPR eligibility (49.3%), while the prehospital ground-based system showed a more than two-fold increase (28.4%). CONCLUSIONS: The study demonstrates a two-fold increase in ECPR eligibility for a prehospital ECPR ground-based system and a four-fold increase for a prehospital ECPR HEMS-based system compared to the current hospital-based ECPR system. This novel GIS model can inform future ECPR implementation strategies, optimizing systems of care.

6.
Nano Lett ; 23(17): 8013-8021, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37615624

RESUMEN

The rapid proliferative biological behavior of primary foci of anaplastic thyroid cancer (ATC) makes it a lethal tumor. According to the specific iodine uptake capacity of thyroid cells and enhanced endocytosis of ATC cells, we designed a kind of nanoclay drug-loading system and showed a promising treatment strategy for ATC. Introducing potassium iodide (KI) improves the homoaggregation of clay nanoparticles and then affects the distribution of nanoparticles in vivo, which makes KI@DOX-KaolinMeOH enriched almost exclusively in thyroid tissue. Simultaneously, the improvement of dispersibility of KI@DOX-KaolinMeOH changes the target uptake of ATC cells by improving the endocytosis and nanoparticle-induced autophagy, which regulate the production of autolysosomes and autophagy-enhanced chemotherapy, eventually contributing to a tumor inhibition rate of more than 90% in the primary foci of ATC. Therefore, this facile strategy to improve the homoaggregation of nanoclay by introducing KI has the potential to become an advanced drug delivery vehicle in ATC treatment.


Asunto(s)
Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides , Humanos , Carcinoma Anaplásico de Tiroides/tratamiento farmacológico , Yoduro de Potasio/farmacología , Yoduro de Potasio/uso terapéutico , Caolín , Endocitosis , Sistemas de Liberación de Medicamentos , Neoplasias de la Tiroides/tratamiento farmacológico
7.
Am Nat ; 200(2): 193-201, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35905401

RESUMEN

AbstractResource competition theory predicts coexistence and exclusion patterns based on species' R*s, the minimum resource values required for a species to persist. A central assumption of the theory is that all species have equal access to resources. However, many systems are characterized by preemption exploitation, where some species deplete resources before their competitors can access them (e.g., asymmetric light competition, contest competition among animals). We hypothesized that coexistence under preemption requires an R*-preemption trade-off-that is, the species with the priority access should have a higher R* (lower "efficiency"). Thus, we developed an extension of resource competition theory to investigate partial and total preemption (in the latter, the preemptor is unaffected by species with lower preemption rank). We found that an R*-preemption trade-off is a necessary condition for coexistence in all models. Moreover, under total preemption, the trade-off alone is sufficient for coexistence. In contrast, under partial preemption, more conditions are needed, which restricts the parameter space of coexistence. Finally, we discuss the implications of our finding for seemingly distinct trade-offs, which we view as special cases of the R*-preemption trade-off. These trade-offs include the digger-grazer trade-off, the competition-colonization trade-off, and trade-offs related to light competition between trees and understories.


Asunto(s)
Ecosistema , Árboles , Animales , Modelos Biológicos
8.
Langmuir ; 37(8): 2816-2825, 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33591771

RESUMEN

Manganese oxides composed of various valence states Mnx+ (x = 2, 3, and 4) have attracted wide attention as promising electrode materials for asymmetric supercapacitor. However, the poor electrical conductivity limited their performance and application. Appropriate regulation content of Mnx+ in mixed-valent manganese oxide can tune the electronic structure and further improve their conductivity and performance. Herein, we prepared manganese oxides with different Mn2+/Mn3+ ratios through an over-reduction (OR) strategy for tuning the internal electron structure of mixed-valent manganese, which could make these material oxides a good platform for researching the structure-property relationships. The Mn2+/Mn3+ ratio of manganese oxide could be precisely tuned from 0.6 to 1.7 by controlling the amount of reducing agent for manipulating the redox processes, where the manganese oxide electrode with the most appropriate Mn2+/Mn3+ ratio, as 1.65 (OR4) exhibits large capacitance (274 F g-1) and the assembling asymmetric supercapacitors by combining OR4 (positive) and the commercial activated carbon (as negative) achieved large 2.0 V voltage window and high energy density of 27.7 Wh kg-1 (power density of 500 W kg-1). The cycle lifespan of the OR4//AC could keep about 92.9% after 10 000-cycle tests owing to the Jahn-Teller distortion of the Mn(III)O6 octahedron, which is more competitive compared to other work. Moreover, a red-light-emitting diode (LED) can easily be lit for 15 min by two all-solid supercapacitor devices in a series.

9.
Nanotechnology ; 32(47)2021 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-34384073

RESUMEN

Lithium-sulfur battery is expected to become a new generation of commercial battery owing to its ultra-high theoretical specific capacity, low-cost, and environmental benign. However, the inherent insulation of sulfur and the shuttle effect of lithium polysulfide between electrodes limit the application of lithium-sulfur battery. In order to solve these problems, we focus on the design of carbon-sulfur composite structure. Herein, CS-CNTs homojunctions featured with the carbon nanotubes (CNTs)in situgrown on carbon sphere (CS) is designed and synthesized by simple polymerization and heat treatment. The composites of CS with interconnected pore networks and CNTs with high conductivity not only offer a conductive framework to promote fast electron transmission, but also provide a larger space to load sulfur and effectively capture polysulfides. The CS-CNTs@S cathode shows better electrochemical performance compared with CS-CPs@S and CS@S. The first discharge specific capacity is 1053 mAh g-1at 0.1 C. After 200 cycles, the specific capacity still remains at 427 mAh g-1.

10.
Ann Stat ; 49(4): 1999-2020, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34621096

RESUMEN

Distance correlation has become an increasingly popular tool for detecting the nonlinear dependence between a pair of potentially high-dimensional random vectors. Most existing works have explored its asymptotic distributions under the null hypothesis of independence between the two random vectors when only the sample size or the dimensionality diverges. Yet its asymptotic null distribution for the more realistic setting when both sample size and dimensionality diverge in the full range remains largely underdeveloped. In this paper, we fill such a gap and develop central limit theorems and associated rates of convergence for a rescaled test statistic based on the bias-corrected distance correlation in high dimensions under some mild regularity conditions and the null hypothesis. Our new theoretical results reveal an interesting phenomenon of blessing of dimensionality for high-dimensional distance correlation inference in the sense that the accuracy of normal approximation can increase with dimensionality. Moreover, we provide a general theory on the power analysis under the alternative hypothesis of dependence, and further justify the capability of the rescaled distance correlation in capturing the pure nonlinear dependency under moderately high dimensionality for a certain type of alternative hypothesis. The theoretical results and finite-sample performance of the rescaled statistic are illustrated with several simulation examples and a blockchain application.

11.
J Nat Prod ; 83(4): 1118-1130, 2020 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-32141747

RESUMEN

This paper describes the isolation and characterization of 17 new and 12 known terpenoids from the fruit of Gardenia jasminoides. The structures of eight new triterpenoids and nine new monoterpenoids, including their absolute configurations, were defined by spectroscopic analysis in combination of quantum chemical electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and gauge-independent atomic orbital (GIAO) NMR calculations. The cytoprotective effects of the isolated compounds against lipopolysaccharide (LPS)-induced apoptosis in normal rat kidney tubule epithelioid (NRK 52e) cells were investigated in vitro. Compounds 10, 18, 20, 21, 24, and 26 exhibited significant protective effects with EC50 values from 14.2 nM to 1.6 µM.


Asunto(s)
Gardenia/química , Lipopolisacáridos/química , Monoterpenos/química , Terpenos/química , Triterpenos/análisis , Animales , Dicroismo Circular , Frutas/química , Espectroscopía de Resonancia Magnética , Monoterpenos/análisis , Ratas , Terpenos/análisis , Triterpenos/química , Triterpenos/aislamiento & purificación
12.
Dermatol Ther ; 33(2): e13265, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32052534

RESUMEN

Lichen aureus is a particularly rare subtype of pigmented purpuric dermatosis and is characterized by the sudden appearance of golden or rust-colored macules or needle-tip-sized flat papules (concentrated in one region to form lichenoid papules) on the lower limbs. These skin lesions are usually confined to an isolated, unilateral distribution, and linear segmental distribution is rare. In this report, we have documented one such case, where the lesions on the limb were arranged in strips (segmental distribution) that roughly followed the direction of the venous drainage. And the first attack and subsequent aggravation were both associated with the onset of allergic rhinitis, a Type I hypersensitivity.


Asunto(s)
Eccema , Exantema , Queratosis , Enfermedades de la Piel , Niño , Humanos , Prurito
13.
Arterioscler Thromb Vasc Biol ; 38(11): 2665-2677, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30354240

RESUMEN

Objective- Mitochondria are the important yet most underutilized target for cardio-cerebrovascular function integrity and disorders. The Tom (translocases of outer membrane) complex are the critical determinant of mitochondrial homeostasis for making organs acclimate physiological and pathological insults; however, their roles in the vascular system remain unknown. Approach and Results- A combination of studies in the vascular-specific transgenic zebrafish and genetically engineered mice was conducted. Vascular casting and imaging, endothelial angiogenesis, and mitochondrial protein import were performed to dissect potential mechanisms. A loss-of-function genetic screening in zebrafish identified that selective inactivation of the tomm7 (translocase of outer mitochondrial membrane 7) gene, which encodes a small subunit of the Tom complex, specially impaired cerebrovascular network formation. Ablation of the ortholog Tomm7 in mice recapitulated cerebrovascular abnormalities. Restoration of the cerebrovascular anomaly by an endothelial-specific transgenesis of tomm7 further indicated a defect in endothelial function. Mechanistically, Tomm7 deficit in endothelial cells induced an increased import of Rac1 (Ras-related C3 botulinum toxin substrate 1) protein into mitochondria and facilitated the mitochondrial Rac1-coupled redox signaling, which incurred angiogenic impairment that underlies cerebrovascular network malformation. Conclusions- Tomm7 drives brain angiogenesis and cerebrovascular network formation through modulating mitochondrial Rac1 signaling within the endothelium.


Asunto(s)
Encéfalo/irrigación sanguínea , Proteínas Portadoras/metabolismo , Células Endoteliales/enzimología , Endotelio Vascular/enzimología , Proteínas de la Membrana/metabolismo , Mitocondrias/enzimología , Proteínas Mitocondriales/metabolismo , Neovascularización Fisiológica , Neuropéptidos/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Animales , Proteínas Portadoras/genética , Células Cultivadas , Trastornos Cerebrovasculares/enzimología , Trastornos Cerebrovasculares/genética , Endotelio Vascular/embriología , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Humanos , Proteínas de la Membrana/genética , Ratones Noqueados , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Proteínas Mitocondriales/genética , Neovascularización Fisiológica/genética , Neuropéptidos/genética , Transducción de Señal , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/genética , Proteína de Unión al GTP rac1/genética
14.
Carcinogenesis ; 39(12): 1438-1446, 2018 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-30169594

RESUMEN

Accumulating evidence suggests that long non-coding RNA (lncRNA) plays important roles in some malignant tumors. However, the mechanism underlying how lncRNA regulates hepatocellular carcinoma (HCC) process remains largely unknown. In this study, we explored the potential role of lncRNA 00607 as a novel tumor suppressor in HCC. In this study, we examined the regulation of lncRNA 00607 by the important inflammatory cytokine tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). We also determined the expression of LINC000607 in 159 HCC tumors and paired adjacent tissues. Effects of LINC000607 in HCC proliferation and apoptosis were examined in vitro in HCC cell lines and in vivo tumor xenografts. Furthermore, we also examine underlying mechanism by which lncRNA 00607 regulates NF-κB p65 and how LIN00607 exerts its tumor suppressor role in HCC. We found that lncRNA 00607 expression level is lower in HCC tumors compared with matched normal liver tissue, and its low expression predicts worse prognosis in HCC. Functionally, lncRNA 00607 overexpression leads to decreased HCC cell proliferation in vitro and in vivo, enhanced apoptosis and chemotherapeutic drug sensitivity. Mechanistically, lncRNA 00607 inhibits the p65 transcription by binding to the p65 promoter region, therefore contributing to increased p53 levels in HCC. Taken together, the findings of this study show that the TNF-α/IL-6-lncRNA 00607-NF-κB p65/p53 signaling axis represents a novel therapeutic avenue in cancer chemotherapy.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , ARN Largo no Codificante/genética , Transducción de Señal/genética , Factor de Transcripción ReIA/genética , Proteína p53 Supresora de Tumor/genética , Animales , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Células Hep G2 , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Regiones Promotoras Genéticas/genética , Transcripción Genética/genética
15.
Ecology ; 99(4): 848-857, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29345307

RESUMEN

Exceptions to the generality of the stress-gradient hypothesis (SGH) may be reconciled by considering species-specific traits and stress tolerance strategies. Studies have tested stress tolerance and competitive ability in mediating interaction outcomes, but few have incorporated this to predict how species interactions shift between competition and facilitation along stress gradients. We used field surveys, salt tolerance and competition experiments to develop a predictive model interspecific interaction shifts across salinity stress gradients. Field survey and greenhouse tolerance tests revealed tradeoffs between stress tolerance and competitive ability. Modeling showed that along salinity gradients, (1) plant interactions shifted from competition to facilitation at high salinities within the physiological limits of salt-intolerant plants, (2) facilitation collapsed when salinity stress exceeded the physiological tolerance of salt-intolerant plants, and (3) neighbor removal experiments overestimate interspecific facilitation by including intraspecific effects. A community-level field experiment, suggested that (1) species interactions are competitive in benign and, facilitative in harsh condition, but fuzzy under medium environmental stress due to niche differences of species and weak stress amelioration, and (2) the SGH works on strong but not weak stress gradients, so SGH confusion arises when it is applied across questionable stress gradients. Our study clarifies how species interactions vary along stress gradients. Moving forward, focusing on SGH applications rather than exceptions on weak or nonexistent gradients would be most productive.


Asunto(s)
Ecosistema , Plantas , Salinidad , Especificidad de la Especie , Estrés Fisiológico
16.
Ann Stat ; 46(3): 989-1017, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29942099

RESUMEN

Over the last two decades, many exciting variable selection methods have been developed for finding a small group of covariates that are associated with the response from a large pool. Can the discoveries by such data mining approaches be spurious due to high dimensionality and limited sample size? Can our fundamental assumptions on exogeneity of covariates needed for such variable selection be validated with the data? To answer these questions, we need to derive the distributions of the maximum spurious correlations given certain number of predictors, namely, the distribution of the correlation of a response variable Y with the best s linear combinations of p covariates X, even when X and Y are independent. When the covariance matrix of X possesses the restricted eigenvalue property, we derive such distributions for both finite s and diverging s, using Gaussian approximation and empirical process techniques. However, such a distribution depends on the unknown covariance matrix of X. Hence, we use the multiplier bootstrap procedure to approximate the unknown distributions and establish the consistency of such a simple bootstrap approach. The results are further extended to the situation where residuals are from regularized fits. Our approach is then applied to construct the upper confidence limit for the maximum spurious correlation and testing exogeneity of covariates. The former provides a baseline for guarding against false discoveries due to data mining and the latter tests whether our fundamental assumptions for high-dimensional model selection are statistically valid. Our techniques and results are illustrated by both numerical examples and real data analysis.

17.
J Hepatol ; 67(2): 293-301, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28323123

RESUMEN

BACKGROUND & AIMS: Identifying target genetic mutations in hepatocellular carcinoma (HCC) for therapy is made challenging by intratumoral heterogeneity. Circulating cell-free DNAs (cfDNA) may contain a more complete mutational spectrum compared to a single tumor sample. This study aimed to identify the most efficient strategy to identify all the mutations within heterogeneous HCCs. METHODS: Whole exome sequencing (WES) and targeted deep sequencing (TDS) were carried out in 32 multi-regional tumor samples from five patients. Matched preoperative cfDNAs were sequenced accordingly. Intratumoral heterogeneity was measured using the average percentage of non-ubiquitous mutations (present in parts of tumor regions). Profiling efficiencies of single tumor specimen and cfDNA were compared. The strategy with the highest performance was used to screen for actionable mutations. RESULTS: Variable levels of heterogeneity with branched and parallel evolution patterns were observed. The heterogeneity decreased at higher sequencing depth of TDS compared to measurements by WES (28.1% vs. 34.9%, p<0.01) but remained unchanged when additional samples were analyzed. TDS of single tumor specimen identified an average of 70% of the total mutations from multi-regional tissues. Although genome profiling efficiency of cfDNA increased with sequencing depth, an average of 47.2% total mutations were identified using TDS, suggesting that tissue samples outperformed it. TDS of single tumor specimen in 66 patients and cfDNAs in four unresectable HCCs showed that 38.6% (26/66 and 1/4) of patients carried mutations that were potential therapeutic targets. CONCLUSIONS: TDS of single tumor specimen could identify actionable mutations targets for therapy in HCC. cfDNA may serve as secondary alternative in profiling HCC genome. LAY SUMMARY: Targeted deep sequencing of single tumor specimen is a more efficient method to identify mutations in hepatocellular carcinoma made from mixed subtypes compared to circulating cell-free DNA in blood. cfDNA may serve as secondary alternative in profiling HCC genome. Identifying mutations may help clinicians choose targeted therapy for better individual treatments.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Terapia Molecular Dirigida , Mutación , Variaciones en el Número de Copia de ADN , Análisis Mutacional de ADN , ADN de Neoplasias/sangre , ADN de Neoplasias/genética , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Filogenia , Análisis de Secuencia de ADN , Secuenciación del Exoma
19.
Tumour Biol ; 37(7): 9909-17, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26813566

RESUMEN

Chemokine receptor-like 1 (CCRL1) has the potential in creating a low level of CCL19 and CCL21 to hinder CCR7(+) cell tracking to tumor tissue. Previously, we found a tumor suppressive role of CCRL1 by impairing CCR7-related chemotaxis of tumor cells in human hepatocellular carcinoma (HCC). Here, we reported a contribution of CCR7(+) mononuclear cells in the tumor microenvironment to the progression of disease. Immunohistochemistry was used to investigate the distribution and clinical significance of CCR7(+) cells in a cohort of 240 HCC patients. Furthermore, the phenotype, composition, and functional status of CCR7(+) cells were determined by flow cytometry, immunofluorescence, and in vitro co-culture assays. We found that CCR7(+) mononuclear cells were dispersed around tumor tissue and negatively related to tumoral expression of CCRL1 (P < 0.001, r = 0.391). High density of CCR7(+) mononuclear cells positively correlated with the absence of tumor capsule, vascular invasion, and poor differentiation (P < 0.05). Survival analyses revealed that increased number of CCR7(+) mononuclear cells was significantly associated with worse survival and increased recurrence. We found that CCR7(+) mononuclear cells featured a naive Treg-like phenotype (CD45RA(+)CD25(+)FOXP3(+)) and possessed tumor-promoting potential by producing TGF-ß1. Moreover, CCR7(+) cells were also composed of several immunocytes, a third of which were CD8(+) T cells. CCR7(+) Treg-like cells facilitate tumor growth and indicate unfavorable prognosis in HCC patients, but fortunately, their tracking to tumor tissue is under the control of CCRL1.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/inmunología , Neoplasias Hepáticas/inmunología , Recurrencia Local de Neoplasia/inmunología , Receptores CCR7/metabolismo , Receptores CCR/metabolismo , Linfocitos T Reguladores/inmunología , Apoptosis , Western Blotting , Linfocitos T CD8-positivos/inmunología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Proliferación Celular , Quimiocina CCL19/metabolismo , Quimiocina CCL21/metabolismo , Estudios de Cohortes , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Factor de Crecimiento Transformador beta1/metabolismo , Células Tumorales Cultivadas , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
20.
J Craniofac Surg ; 27(1): e77-80, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26703040

RESUMEN

PURPOSE: This report presented a patient with 2 long-term broken roots displaced in left maxillary sinus. The residual root fragments made the patient uncomfortable in both mind and body and interfered with prosthodontics work. The application of endoscope combined with piezoelectric device both helps in removing the broken roots successfully with minimally surgical injury and preserves the residual alveolar bone. METHODS: Computed tomography scans and 3-dimensional reconstructions located the broken roots. A 1.0 cm × 1.5  cm rectangle bone window on anterolateral sinus wall was opened by a piezoelectric device to place the endoscope and forcep into sinus. Two broken roots could be observed clearly via a endoscopic screen. They were removed by a mini goblet forcep completely and efficiently. A whole bone lid was replaced with a biological membrane to help repair bone defect after removing procedure. RESULTS: The operation is about 20 minutes with endoscope and piezoelectric device helped to save a lot of time and provided excellent visual surgical field. Main postoperative adverse effects were swelling, numbness, and temporal no-vitality for the first premolar (24). Three months later, computed tomography shows the Schneiderian membrane thinned to around 0.8  mm. The bone lid is on its position and starts to perform synostosis. The 24 tooth is still dysesthetic and needs time to recover. CONCLUSIONS: Endoscopic surgery combined with a piezoelectric device has obvious advantage of minimizing surgical injury and providing excellent visibility of surgical field when removing long-term foreign bodies in maxillary sinus. It is efficient and protects the residual alveolar bone.


Asunto(s)
Endoscopía/métodos , Cuerpos Extraños/cirugía , Seno Maxilar/cirugía , Fracturas de los Dientes/cirugía , Raíz del Diente/lesiones , Adulto , Diente Premolar/patología , Prueba de la Pulpa Dental , Endoscopios , Femenino , Estudios de Seguimiento , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Membranas Artificiales , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Diente Molar/lesiones , Tercer Molar/lesiones , Mucosa Nasal/cirugía , Osteotomía/instrumentación , Osteotomía/métodos , Piezocirugía/instrumentación , Piezocirugía/métodos , Tomografía Computarizada por Rayos X/métodos , Raíz del Diente/cirugía
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