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1.
EMBO J ; 41(16): e110439, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35781818

RESUMEN

Brown adipose tissue (BAT) functions as a thermogenic organ and is negatively associated with cardiometabolic diseases. N6 -methyladenosine (m6 A) modulation regulates the fate of stem cells. Here, we show that the prostaglandin E2 (PGE2 )-E-prostanoid receptor 3 (EP3) axis was activated during mouse interscapular BAT development. Disruption of EP3 impaired the browning process during adipocyte differentiation from pre-adipocytes. Brown adipocyte-specific depletion of EP3 compromised interscapular BAT formation and aggravated high-fat diet-induced obesity and insulin resistance in vivo. Mechanistically, activation of EP3 stabilized the Zfp410 mRNA via WTAP-mediated m6 A modification, while knockdown of Zfp410 abolished the EP3-induced enhancement of brown adipogenesis. EP3 prevented ubiquitin-mediated degradation of WTAP by eliminating PKA-mediated ERK1/2 inhibition during brown adipocyte differentiation. Ablation of WTAP in brown adipocytes abrogated the protective effect of EP3 overexpression in high-fat diet-fed mice. Inhibition of EP3 also retarded human embryonic stem cell differentiation into mature brown adipocytes by reducing the WTAP levels. Thus, a conserved PGE2 -EP3 axis promotes BAT development by stabilizing WTAP/Zfp410 signaling in a PKA/ERK1/2-dependent manner.


Asunto(s)
Tejido Adiposo Pardo , Dinoprostona , Adipocitos Marrones/metabolismo , Tejido Adiposo Pardo/metabolismo , Animales , Proteínas de Ciclo Celular/metabolismo , Dinoprostona/metabolismo , Humanos , Metiltransferasas/metabolismo , Ratones , ARN/metabolismo , Factores de Empalme de ARN/metabolismo , Subtipo EP3 de Receptores de Prostaglandina E , Termogénesis
2.
Am J Hum Genet ; 109(10): 1923-1931, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36067766

RESUMEN

MTSS2, also known as MTSS1L, binds to plasma membranes and modulates their bending. MTSS2 is highly expressed in the central nervous system (CNS) and appears to be involved in activity-dependent synaptic plasticity. Variants in MTSS2 have not yet been associated with a human phenotype in OMIM. Here we report five individuals with the same heterozygous de novo variant in MTSS2 (GenBank: NM_138383.2: c.2011C>T [p.Arg671Trp]) identified by exome sequencing. The individuals present with global developmental delay, mild intellectual disability, ophthalmological anomalies, microcephaly or relative microcephaly, and shared mild facial dysmorphisms. Immunoblots of fibroblasts from two affected individuals revealed that the variant does not significantly alter MTSS2 levels. We modeled the variant in Drosophila and showed that the fly ortholog missing-in-metastasis (mim) was widely expressed in most neurons and a subset of glia of the CNS. Loss of mim led to a reduction in lifespan, impaired locomotor behavior, and reduced synaptic transmission in adult flies. Expression of the human MTSS2 reference cDNA rescued the mim loss-of-function (LoF) phenotypes, whereas the c.2011C>T variant had decreased rescue ability compared to the reference, suggesting it is a partial LoF allele. However, elevated expression of the variant, but not the reference MTSS2 cDNA, led to similar defects as observed by mim LoF, suggesting that the variant is toxic and may act as a dominant-negative allele when expressed in flies. In summary, our findings support that mim is important for appropriate neural function, and that the MTSS2 c.2011C>T variant causes a syndromic form of intellectual disability.


Asunto(s)
Discapacidad Intelectual , Microcefalia , Malformaciones del Sistema Nervioso , Animales , ADN Complementario , Drosophila/genética , Humanos , Discapacidad Intelectual/genética , Discapacidad Intelectual/patología , Proteínas de la Membrana , Microcefalia/genética , Proteínas de Microfilamentos , Mutación Missense/genética , Malformaciones del Sistema Nervioso/genética , Fenotipo
3.
J Biol Chem ; 299(3): 102914, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36649907

RESUMEN

Epithelial Na+ channels (ENaCs) and related channels have large extracellular domains where specific factors interact and induce conformational changes, leading to altered channel activity. However, extracellular structural transitions associated with changes in ENaC activity are not well defined. Using crosslinking and two-electrode voltage clamp in Xenopus oocytes, we identified several pairs of functional intersubunit contacts where mouse ENaC activity was modulated by inducing or breaking a disulfide bond between introduced Cys residues. Specifically, crosslinking E499C in the ß-subunit palm domain and N510C in the α-subunit palm domain activated ENaC, whereas crosslinking ßE499C with αQ441C in the α-subunit thumb domain inhibited ENaC. We determined that bridging ßE499C to αN510C or αQ441C altered the Na+ self-inhibition response via distinct mechanisms. Similar to bridging ßE499C and αQ441C, we found that crosslinking palm domain αE557C with thumb domain γQ398C strongly inhibited ENaC activity. In conclusion, we propose that certain residues at specific subunit interfaces form microswitches that convey a conformational wave during ENaC gating and its regulation.


Asunto(s)
Canales Epiteliales de Sodio , Oocitos , Animales , Ratones , Canales Epiteliales de Sodio/metabolismo , Iones , Conformación Molecular , Oocitos/metabolismo , Dominios Proteicos , Xenopus
4.
Clin Gastroenterol Hepatol ; 22(11): 2250-2260.e12, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38906440

RESUMEN

BACKGROUND AND AIMS: The global rise of chronic hepatitis B (CHB) superimposed on hepatic steatosis (HS) warrants noninvasive, precise tools for assessing fibrosis progression. This study leveraged machine learning (ML) to develop diagnostic models for advanced fibrosis and cirrhosis in this patient population. METHODS: Treatment-naive CHB patients with concurrent HS who underwent liver biopsy in 10 medical centers were enrolled as a training cohort and an independent external validation cohort (NCT05766449). Six ML models were implemented to predict advanced fibrosis and cirrhosis. The final models, derived from SHAP (Shapley Additive exPlanations), were compared with Fibrosis-4 Index, nonalcoholic fatty liver disease Fibrosis Score, and aspartate aminotransferase-to-platelet ratio index using the area under receiver-operating characteristic curve (AUROC) and decision curve analysis (DCA). RESULTS: Of 1,198 eligible patients, the random forest model achieved AUROCs of 0.778 (95% confidence interval [CI], 0.749-0.807) for diagnosing advanced fibrosis (random forest advanced fibrosis model) and 0.777 (95% CI, 0.748-0.806) for diagnosing cirrhosis (random forest cirrhosis model) in the training cohort, and maintained high AUROCs in the validation cohort. In the training cohort, the random forest advanced fibrosis model obtained an AUROC of 0.825 (95% CI, 0.787-0.862) in patients with hepatitis B virus DNA ≥105 IU/mL, and the random forest cirrhosis model had an AUROC of 0.828 (95% CI, 0.774-0.883) in female patients. The 2 models outperformed Fibrosis-4 Index, nonalcoholic fatty liver disease Fibrosis Score, and aspartate aminotransferase-to-platelet ratio index in the training cohort, and also performed well in the validation cohort. CONCLUSIONS: The random forest models provide reliable, noninvasive tools for identifying advanced fibrosis and cirrhosis in CHB patients with concurrent HS, offering a significant advancement in the comanagement of the 2 diseases. CLINICALTRIALS: gov, Number: NCT05766449.


Asunto(s)
Hepatitis B Crónica , Cirrosis Hepática , Aprendizaje Automático , Humanos , Hepatitis B Crónica/complicaciones , Femenino , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología , Masculino , Adulto , Persona de Mediana Edad , Hígado Graso/diagnóstico , Hígado Graso/patología , Biopsia/métodos , Curva ROC , Hígado/patología
5.
Eur J Nucl Med Mol Imaging ; 51(6): 1582-1592, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38246910

RESUMEN

PURPOSE: Programmed cell death protein ligand 1 (PD-L1) is a crucial biomarker for immunotherapy. However, nearly 70% of patients do not respond to PD-L1 immune checkpoint therapy. Accurate monitoring of PD-L1 expression and quantification of target binding during treatment are essential. In this study, a series of small-molecule radiotracers were developed to assess PD-L1 expression and direct immunotherapy. METHODS: Radiotracers of [68Ga]Ga-D-PMED, [68Ga]Ga-D-PEG-PMED, and [68Ga]Ga-D-pep-PMED were designed based on a 2-methyl-3-biphenyl methanol scaffold and successfully synthesized. Cellular experiments and molecular docking assays were performed to determine their specificity for PD-L1. PD-L1 status was investigated via positron emission tomography (PET) imaging in MC38 tumor models. PET imaging of [68Ga]Ga-D-pep-PMED was performed to noninvasively quantify PD-L1 blocking using an anti-mouse PD-L1 antibody (PD-L1 mAb). RESULTS: The radiosyntheses of [68Ga]Ga-D-PMED, [68Ga]Ga-D-PEG-PMED, and [68Ga]Ga-D-pep-PMED were achieved with radiochemical yields of 87 ± 6%, 82 ± 4%, and 79 ± 9%, respectively. In vitro competition assays demonstrated their high affinities (the IC50 values of [68Ga]Ga-D-PMED, [68Ga]Ga-D-PEG-PMED, and [68Ga]Ga-D-pep-PMED were 90.66 ± 1.24, 160.8 ± 1.35, and 51.6 ± 1.32 nM, respectively). At 120 min postinjection (p.i.) of the radiotracers, MC38 tumors displayed optimized tumor-to-muscle ratios for all radioligands. Owing to its hydrophilic modification, [68Ga]Ga-D-pep-PMED had the highest target-to-nontarget (T/NT) ratio of approximately 6.2 ± 1.2. Interestingly, the tumor/liver ratio was hardly affected by different concentrations of the inhibitor BMS202. We then evaluated the impacts of dose and time on accessible PD-L1 levels in the tumor during anti-mouse PD-L1 antibody treatment. The tumor uptake of [68Ga]Ga-D-pep-PMED significantly decreased with increasing PD-L1 mAb dose. Moreover, after 8 days of treatment with a single antibody, the uptake of [68Ga]Ga-D-pep-PMED in the tumor significantly increased but remained lower than that in the saline group. CONCLUSION: PET imaging with [68Ga]Ga-D-pep-PMED, a small-molecule radiotracer, is a promising tool for evaluating PD-L1 expression and quantifying the target blockade of PD-L1 to assist in the development of effective therapeutic regimens.


Asunto(s)
Acetamidas , Antígeno B7-H1 , Tomografía de Emisión de Positrones , Piridinas , Inmunoterapia , Antígeno B7-H1/análisis , Antígeno B7-H1/antagonistas & inhibidores , Humanos , Animales , Ratones , Línea Celular Tumoral , Células A549 , Compuestos Organometálicos , Radioisótopos de Galio , Acetamidas/química , Piridinas/química
6.
Am J Med Genet A ; 194(5): e63522, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38131126

RESUMEN

Despite significant advancements in rare genetic disease diagnostics, many patients with rare genetic disease remain without a molecular diagnosis. Novel tools and methods are needed to improve the detection of disease-associated variants and understand the genetic basis of many rare diseases. Long-read genome sequencing provides improved sequencing in highly repetitive, homologous, and low-complexity regions, and improved assessment of structural variation and complex genomic rearrangements compared to short-read genome sequencing. As such, it is a promising method to explore overlooked genetic variants in rare diseases with a high suspicion of a genetic basis. We therefore applied PacBio HiFi sequencing in a large multi-generational family presenting with autosomal dominant 46,XY differences of sexual development (DSD), for whom extensive molecular testing over multiple decades had failed to identify a molecular diagnosis. This revealed a rare SINE-VNTR-Alu retroelement insertion in intron 4 of NR5A1, a gene in which loss-of-function variants are an established cause of 46,XY DSD. The insertion segregated among affected family members and was associated with loss-of-expression of alleles in cis, demonstrating a functional impact on NR5A1. This case highlights the power of long-read genome sequencing to detect genomic variants that have previously been intractable to detection by standard short-read genomic testing.


Asunto(s)
Trastorno del Desarrollo Sexual 46,XY , Retroelementos , Humanos , Mutación , Intrones/genética , Retroelementos/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Enfermedades Raras/genética , Desarrollo Sexual , Factor Esteroidogénico 1/genética
7.
Mol Pharm ; 21(10): 4960-4969, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39279392

RESUMEN

The limited progress in treatment options and the alarming survival rates in advanced melanoma emphasize the significant research importance of early melanoma diagnosis. RFVT3, a crucial protein at the core of energy metabolism reprogramming in melanoma, might play a pivotal role in early detection. In this study, [68Ga]Ga-NOTA-RF, based on riboflavin (RF), was rationally developed and validated, serving as an innovative tool for positron emission tomography (PET) imaging of RFVT3 expression in melanoma. The in vitro assays of RFVT3 specificity of [68Ga]Ga-NOTA-RF were performed on B16F10 melanoma cells. Then, PET imaging of melanoma was investigated in B16F10 allograft mouse models with varying volumes. Biodistribution studies are used to clarify the behavior of [68Ga]Ga-NOTA-RF in vivo. [68Ga]Ga-NOTA-RF was obtained with high radiochemical purity (>95%). A significant uptake (37.79 ± 6.86%, n = 4) of [68Ga]Ga-NOTA-RF was observed over time in B16F10 melanoma cells, which was significantly inhibited by RFVT3 inhibitors RF or methylene blue (MB), demonstrating the specific binding of [68Ga]Ga-NOTA-RF. At 60 min postinjection, the tumor-to-muscle (T/M) ratio of [68Ga]Ga-NOTA-RF was 4.03 ± 0.34, higher than that of the RF-blocked group (2.63 ± 0.19) and MB-blocked group (2.14 ± 0.20). The T/M ratios for three distinct tumor volumes-small (5 mm), medium (10 mm), and large (15 mm) were observed to be 5.25 ± 0.28, 4.03 ± 0.34, and 3.19 ± 0.55, respectively. The expression of RFVT3 was validated by immunohistochemical staining in various tumor models, with small B16F10 tumors exhibiting the highest expression. [68Ga]Ga-NOTA-RF demonstrates promising properties for the early diagnosis of melanoma and the examination of minute metastatic lesions, indicating its potential to assist in guiding clinical treatment decisions.


Asunto(s)
Radioisótopos de Galio , Melanoma Experimental , Tomografía de Emisión de Positrones , Riboflavina , Animales , Ratones , Tomografía de Emisión de Positrones/métodos , Riboflavina/química , Melanoma Experimental/diagnóstico por imagen , Melanoma Experimental/metabolismo , Línea Celular Tumoral , Distribución Tisular , Ratones Endogámicos C57BL , Radiofármacos/química , Radiofármacos/farmacocinética , Melanoma/diagnóstico por imagen , Melanoma/metabolismo , Melanoma/patología , Melanoma/tratamiento farmacológico
8.
Cancer Control ; 31: 10732748241283621, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39275798

RESUMEN

OBJECTIVES: Radiation-induced oropharyngeal injury is a dose-limiting toxicity in head and neck cancer patients. Delineation of the "oropharyngeal mucosa" and limiting its dose to spare the oropharynx was investigated. METHODS: In this retrospective study, computed tomography imaging from eight patients with previously untreated head and neck cancer was employed. An adaptive contouring brush within the planning software Monaco was used to create an air cavity within the oropharynx, and then the air cavity was expanded uniformly 2 mm to create the "oropharyngeal mucosa". Three plans were independently generated for each patient: Plan1: dose constraint was applied for the oropharynx; Plan2: dose constraints were applied for the oropharynx and the "oropharyngeal mucosa"; Plan3: dose constraint was applied for the "oropharyngeal mucosa". T-tests were used to compare the dosimetry variables. RESULTS: All plans had adequate target coverage and there were no statistical differences among plans. The mean dose, D30%, D45%, D50%, D85%, D90%, D95%, D100%, V25 Gy, V30 Gy, V35 Gy, V40 Gy, and V45 Gy of the oropharynx and "oropharyngeal mucosa" in Plan1 were significantly higher than those in Plan2 and Plan3. There were no significant differences between Plan2 and Plan3. There were no significant differences in the dosimetric parameters of any other organs at risk. CONCLUSION: Delineation of the "oropharyngeal mucosa" and limiting its dose should be an easy and effective method to spare the oropharynx.


Radiation-induced oropharyngeal injury is dose-limiting toxicity in head and neck cancer patients. Delineation of "oropharyngeal mucosa" and limiting its dose should be an easy and effective method to spare the oropharynx.


Asunto(s)
Neoplasias de Cabeza y Cuello , Orofaringe , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Humanos , Neoplasias de Cabeza y Cuello/radioterapia , Estudios Retrospectivos , Planificación de la Radioterapia Asistida por Computador/métodos , Orofaringe/efectos de la radiación , Orofaringe/diagnóstico por imagen , Masculino , Órganos en Riesgo/efectos de la radiación , Femenino , Radioterapia de Intensidad Modulada/métodos , Radioterapia de Intensidad Modulada/efectos adversos , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Membrana Mucosa/efectos de la radiación , Traumatismos por Radiación/prevención & control , Traumatismos por Radiación/etiología
9.
Biometrics ; 80(4)2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39499239

RESUMEN

A stepped wedge design is an unidirectional crossover design where clusters are randomized to distinct treatment sequences. While model-based analysis of stepped wedge designs is a standard practice to evaluate treatment effects accounting for clustering and adjusting for covariates, their properties under misspecification have not been systematically explored. In this article, we focus on model-based methods, including linear mixed models and generalized estimating equations with an independence, simple exchangeable, or nested exchangeable working correlation structure. We study when a potentially misspecified working model can offer consistent estimation of the marginal treatment effect estimands, which are defined nonparametrically with potential outcomes and may be functions of calendar time and/or exposure time. We prove a central result that consistency for nonparametric estimands usually requires a correctly specified treatment effect structure, but generally not the remaining aspects of the working model (functional form of covariates, random effects, and error distribution), and valid inference is obtained via the sandwich variance estimator. Furthermore, an additional g-computation step is required to achieve model-robust inference under non-identity link functions or for ratio estimands. The theoretical results are illustrated via several simulation experiments and re-analysis of a completed stepped wedge cluster randomized trial.


Asunto(s)
Modelos Estadísticos , Humanos , Estudios Cruzados , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Simulación por Computador , Biometría/métodos , Interpretación Estadística de Datos , Proyectos de Investigación , Modelos Lineales
10.
Stat Med ; 43(2): 358-378, 2024 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-38009329

RESUMEN

Individually randomized group treatment (IRGT) trials, in which the clustering of outcome is induced by group-based treatment delivery, are increasingly popular in public health research. IRGT trials frequently incorporate longitudinal measurements, of which the proper sample size calculations should account for correlation structures reflecting both the treatment-induced clustering and repeated outcome measurements. Given the relatively sparse literature on designing longitudinal IRGT trials, we propose sample size procedures for continuous and binary outcomes based on the generalized estimating equations approach, employing the block exchangeable correlation structures with different correlation parameters for the treatment arm and for the control arm, and surveying five marginal mean models with different assumptions of time effect: no-time constant treatment effect, linear-time constant treatment effect, categorical-time constant treatment effect, linear time by treatment interaction, and categorical time by treatment interaction. Closed-form sample size formulas are derived for continuous outcomes, which depends on the eigenvalues of the correlation matrices; detailed numerical sample size procedures are proposed for binary outcomes. Through simulations, we demonstrate that the empirical power agrees well with the predicted power, for as few as eight groups formed in the treatment arm, when data are analyzed using the matrix-adjusted estimating equations for the correlation parameters with a bias-corrected sandwich variance estimator.


Asunto(s)
Modelos Estadísticos , Proyectos de Investigación , Humanos , Tamaño de la Muestra , Sesgo , Análisis por Conglomerados , Simulación por Computador
11.
Stat Med ; 43(25): 4796-4818, 2024 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-39225281

RESUMEN

Many individually randomized group treatment (IRGT) trials randomly assign individuals to study arms but deliver treatments via shared agents, such as therapists, surgeons, or trainers. Post-randomization interactions induce correlations in outcome measures between participants sharing the same agent. Agents can be nested in or crossed with trial arm, and participants may interact with a single agent or with multiple agents. These complications have led to ambiguity in choice of models but there have been no systematic efforts to identify appropriate analytic models for these study designs. To address this gap, we undertook a simulation study to examine the performance of candidate analytic models in the presence of complex clustering arising from multiple membership, single membership, and single agent settings, in both nested and crossed designs and for a continuous outcome. With nested designs, substantial type I error rate inflation was observed when analytic models did not account for multiple membership and when analytic model weights characterizing the association with multiple agents did not match the data generating mechanism. Conversely, analytic models for crossed designs generally maintained nominal type I error rates unless there was notable imbalance in the number of participants that interact with each agent.


Asunto(s)
Simulación por Computador , Modelos Estadísticos , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Análisis por Conglomerados , Proyectos de Investigación
12.
Clin Trials ; : 17407745241276137, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377196

RESUMEN

BACKGROUND/AIMS: Stepped-wedge cluster randomized trials tend to require fewer clusters than standard parallel-arm designs due to the switches between control and intervention conditions, but there are no recommendations for the minimum number of clusters. Trials randomizing an extremely small number of clusters are not uncommon, but the justification for small numbers of clusters is often unclear and appropriate analysis is often lacking. In addition, stepped-wedge cluster randomized trials are methodologically more complex due to their longitudinal correlation structure, and ignoring the distinct within- and between-period intracluster correlations can underestimate the sample size in small stepped-wedge cluster randomized trials. We conducted a review of published small stepped-wedge cluster randomized trials to understand how and why they are used, and to characterize approaches used in their design and analysis. METHODS: Electronic searches were used to identify primary reports of full-scale stepped-wedge cluster randomized trials published during the period 2016-2022; the subset that randomized two to six clusters was identified. Two reviewers independently extracted information from each report and any available protocol. Disagreements were resolved through discussion. RESULTS: We identified 61 stepped-wedge cluster randomized trials that randomized two to six clusters: median sample size (Q1-Q3) 1426 (420-7553) participants. Twelve (19.7%) gave some indication that the evaluation was considered a "preliminary" evaluation and 16 (26.2%) recognized the small number of clusters as a limitation. Sixteen (26.2%) provided an explanation for the limited number of clusters: the need to minimize contamination (e.g. by merging adjacent units), limited availability of clusters, and logistical considerations were common explanations. Majority (51, 83.6%) presented sample size or power calculations, but only one assumed distinct within- and between-period intracluster correlations. Few (10, 16.4%) utilized restricted randomization methods; more than half (34, 55.7%) identified baseline imbalances. The most common statistical method for analysis was the generalized linear mixed model (44, 72.1%). Only four trials (6.6%) reported statistical analyses considering small numbers of clusters: one used generalized estimating equations with small-sample correction, two used generalized linear mixed model with small-sample correction, and one used Bayesian analysis. Another eight (13.1%) used fixed-effects regression, the performance of which requires further evaluation under stepped-wedge cluster randomized trials with small numbers of clusters. None used permutation tests or cluster-period level analysis. CONCLUSION: Methods appropriate for the design and analysis of small stepped-wedge cluster randomized trials have not been widely adopted in practice. Greater awareness is required that the use of standard sample size calculation methods can provide spuriously low numbers of required clusters. Methods such as generalized estimating equations or generalized linear mixed models with small-sample corrections, Bayesian approaches, and permutation tests may be more appropriate for the analysis of small stepped-wedge cluster randomized trials. Future research is needed to establish best practices for stepped-wedge cluster randomized trials with a small number of clusters.

13.
Clin Trials ; 21(2): 199-210, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37990575

RESUMEN

BACKGROUND/AIMS: The stepped-wedge cluster randomized trial (SW-CRT), in which clusters are randomized to a time at which they will transition to the intervention condition - rather than a trial arm - is a relatively new design. SW-CRTs have additional design and analytical considerations compared to conventional parallel arm trials. To inform future methodological development, including guidance for trialists and the selection of parameters for statistical simulation studies, we conducted a review of recently published SW-CRTs. Specific objectives were to describe (1) the types of designs used in practice, (2) adherence to key requirements for statistical analysis, and (3) practices around covariate adjustment. We also examined changes in adherence over time and by journal impact factor. METHODS: We used electronic searches to identify primary reports of SW-CRTs published 2016-2022. Two reviewers extracted information from each trial report and its protocol, if available, and resolved disagreements through discussion. RESULTS: We identified 160 eligible trials, randomizing a median (Q1-Q3) of 11 (8-18) clusters to 5 (4-7) sequences. The majority (122, 76%) were cross-sectional (almost all with continuous recruitment), 23 (14%) were closed cohorts and 15 (9%) open cohorts. Many trials had complex design features such as multiple or multivariate primary outcomes (50, 31%) or time-dependent repeated measures (27, 22%). The most common type of primary outcome was binary (51%); continuous outcomes were less common (26%). The most frequently used method of analysis was a generalized linear mixed model (112, 70%); generalized estimating equations were used less frequently (12, 8%). Among 142 trials with fewer than 40 clusters, only 9 (6%) reported using methods appropriate for a small number of clusters. Statistical analyses clearly adjusted for time effects in 119 (74%), for within-cluster correlations in 132 (83%), and for distinct between-period correlations in 13 (8%). Covariates were included in the primary analysis of the primary outcome in 82 (51%) and were most often individual-level covariates; however, clear and complete pre-specification of covariates was uncommon. Adherence to some key methodological requirements (adjusting for time effects, accounting for within-period correlation) was higher among trials published in higher versus lower impact factor journals. Substantial improvements over time were not observed although a slight improvement was observed in the proportion accounting for a distinct between-period correlation. CONCLUSIONS: Future methods development should prioritize methods for SW-CRTs with binary or time-to-event outcomes, small numbers of clusters, continuous recruitment designs, multivariate outcomes, or time-dependent repeated measures. Trialists, journal editors, and peer reviewers should be aware that SW-CRTs have additional methodological requirements over parallel arm designs including the need to account for period effects as well as complex intracluster correlations.


Asunto(s)
Proyectos de Investigación , Humanos , Análisis por Conglomerados , Ensayos Clínicos Controlados Aleatorios como Asunto , Simulación por Computador , Modelos Lineales , Tamaño de la Muestra
14.
J Nanobiotechnology ; 22(1): 101, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38462598

RESUMEN

BACKGROUND: Radiotheranostics differs from the vast majority of other cancer therapies in its capacity for simultaneous imaging and therapy, and it is becoming more widely implemented. A balance between diagnostic and treatment requirements is essential for achieving effective radiotheranostics. Herein, we propose a proof-of-concept strategy aiming to address the profound differences in the specific requirements of the diagnosis and treatment of radiotheranostics. RESULTS: To validate the concept, we designed an s-tetrazine (Tz) conjugated prostate-specific membrane antigen (PSMA) ligand (DOTA-PSMA-Tz) for 68Ga or 177Lu radiolabeling and tumor radiotheranostics, a trans-cyclooctene (TCO) modified Pd@Au nanoplates (Pd@Au-PEG-TCO) for signal amplification, respectively. We then demonstrated this radiotheranostic strategy in the tumor-bearing mice with the following three-step procedures: (1) i.v. injection of the [68Ga]Ga-PSMA-Tz for diagnosis; (2) i.v. injection of the signal amplification module Pd@Au-PEG-TCO; (3) i.v. injection of the [177Lu]Lu-PSMA-Tz for therapy. Firstly, this strategy was demonstrated in 22Rv1 tumor-bearing mice via positron emission tomography (PET) imaging with [68Ga]Ga-PSMA-Tz. We observed significantly higher tumor uptake (11.5 ± 0.8%ID/g) with the injection of Pd@Au-PEG-TCO than with the injection [68Ga]Ga-PSMA-Tz alone (5.5 ± 0.9%ID/g). Furthermore, we validated this strategy through biodistribution studies of [177Lu]Lu-PSMA-Tz, with the injection of the signal amplification module, approximately five-fold higher tumor uptake of [177Lu]Lu-PSMA-Tz (24.33 ± 2.53% ID/g) was obtained when compared to [177Lu]Lu-PSMA-Tz alone (5.19 ± 0.26%ID/g) at 48 h post-injection. CONCLUSION: In summary, the proposed strategy has the potential to expand the toolbox of pretargeted radiotherapy in the field of theranostics.


Asunto(s)
Neoplasias Colorrectales , Radiofármacos , Masculino , Animales , Ratones , Radioisótopos de Galio , Distribución Tisular , Línea Celular Tumoral , Neoplasias Colorrectales/patología
15.
Chem Biodivers ; : e202401538, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39255384

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is closely related to gut microbiota due to the hepatic portal system, and utilizing natural polysaccharides as prebiotics has become a prospective strategy for treating NAFLD. However, the therapeutic effects and potential molecular mechanisms of Lanzhou Lily polysaccharides (LLP) on NAFLD remains unclear. Therefore, the alleviating effects of LLP on NAFLD induced by high-fat diet (HFD) were investigated. LLP treatment greatly ameliorated NAFLD by significantly reducing lipid accumulation and the levels of liver function markers in HFD-induced NAFLD mice, as evidenced by decreased serum levels of TG, TC, HDL-C and LDL-C. Furthermore, LLP administration reduced hepatic steatosis, as shown by H&E and Oil red O staining. LLP also inhibited the TNF-α and IL-1ß expression, thereby reducing levels of hepatic proinflammatory cytokines. Furthermore, LLP restored gut microbiota dysbiosis, and regulated microbial metabolic pathways such as primary bile acid biosynthesis and amino acid metabolism. In addition, the resultes of Spearman's correlation analysis found that some key metabolites in these metabolic pathways were associated with intestinal microorganisms such as Desulfobacterota, Prevotellaceae-UCG-001, Colidextribacter and Alistipes. Therefore, our study suggests that LLP may has potential applications in the treatment of NAFLD by regulating gut microbiota and its metabolite profile.

16.
J Biol Chem ; 298(5): 101860, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35339489

RESUMEN

The epithelial Na+ channel (ENaC)/degenerin family has a similar extracellular architecture, where specific regulatory factors interact and alter channel gating behavior. The extracellular palm domain serves as a key link to the channel pore. In this study, we used cysteine-scanning mutagenesis to assess the functional effects of Cys-modifying reagents on palm domain ß10 strand residues in mouse ENaC. Of the 13 ENaC α subunit mutants with Cys substitutions examined, only mutants at sites in the proximal region of ß10 exhibited changes in channel activity in response to methanethiosulfonate reagents. Additionally, Cys substitutions at three proximal sites of ß and γ subunit ß10 strands also rendered mutant channels methanethiosulfonate-responsive. Moreover, multiple Cys mutants were activated by low concentrations of thiophilic Cd2+. Using the Na+ self-inhibition response to assess ENaC gating behavior, we identified four α, two ß, and two γ subunit ß10 strand mutations that changed the Na+ self-inhibition response. Our results suggest that the proximal regions of ß10 strands in all three subunits are accessible to small aqueous compounds and Cd2+ and have a role in modulating ENaC gating. These results are consistent with a structural model of mouse ENaC that predicts the presence of aqueous tunnels adjacent to the proximal part of ß10 and with previously resolved structures of a related family member where palm domain structural transitions were observed with channels in an open or closed state.


Asunto(s)
Cadmio , Canales Epiteliales de Sodio , Animales , Cisteína , Canales Epiteliales de Sodio/química , Canales Epiteliales de Sodio/genética , Iones , Ratones , Conformación Proteica , Sodio/metabolismo
17.
Anal Chem ; 95(36): 13605-13613, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37594225

RESUMEN

The emergence of the global pandemic and the discovery of nucleic acid biomarkers in cancer diagnosis have fostered the development of more accurate and adaptive molecular diagnosis technologies. Current nucleic acid testing (NAT) methods either lack sensitivity or require tedious amplification operations, which could not meet the need for point-of-care (POC) NAT for on-site and community-based diagnosis. Here, we present a fluorescence one-step-bDNA-based lateral flow assay (FOB-LFA) method for amplification-free NAT to realize point-of-care pathogen detection and disease diagnosis. Take COVID-19 as an example, the developed FOB-LFA demonstrated a high sensitivity of 300 copies/mL for the RNA of the SARS-CoV-2 pseudovirus and exhibited high specificity among various homologous pseudoviruses. Further, the result of oropharyngeal swab sample detection suggested the great potential of FOB-LFA in clinical examination. The outstanding performance of FOB-LFA, including high sensitivity, high specificity, low cost, excellent portability, and minimized risk of nucleic acid leakage and contamination, can meet the POC testing demand for the diagnosis of various infectious and genetic diseases.


Asunto(s)
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , Ensayo de Amplificación de Señal de ADN Ramificado , ARN , ADN
18.
J Med Virol ; 95(12): e29267, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38082564

RESUMEN

We evaluated the characteristics of high-risk human papillomavirus (Hr-HPV) infection in different grades of vaginal intraepithelial neoplasia (VaIN). 7469 participants were involved in this study, of which 601 were diagnosed with VaIN, including single vaginal intraepithelial neoplasia (s-VaIN, n = 369) and VaIN+CIN (n = 232), 3414 with single cervical intraepithelial neoplasia (s-CIN), 3446 with cervicitis or vaginitis and 8 with vaginal cancer. We got those results. First, the most popular HPV genotypes in VaIN were HPV16, 52, 58, 51, and 56. Second, our study showed that higher parity and older age were risk factors for VaIN3 (p < 0.005). Third, the median Hr-HPV load of VaIN+CIN (725) was higher than that of s-CIN (258) (p = 0.027), and the median Hr-HPV load increased with the grade of VaIN. In addition, the risk of VaIN3 was higher in women with single HPV16 infections (p = 0.01), but those with multiple HPV16 infections faced a higher risk of s-VaIN (p = 0.003) or VaIN+CIN (p = 0.01). Our results suggested that women with higher gravidity and parity, higher Hr-HPV load, multiple HPV16 infections, and perimenopause or menopause status faced a higher risk for VaIN, while those with higher parity, single HPV16 infections, and menopause status are more prone to VaIN3.


Asunto(s)
Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Neoplasias Vaginales , Femenino , Humanos , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/diagnóstico , Beijing , Neoplasias Vaginales/diagnóstico , Papillomaviridae/genética
19.
Eur J Nucl Med Mol Imaging ; 50(9): 2846-2860, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37097443

RESUMEN

PURPOSE: Evans blue as an albumin binder has been widely used to improve pharmacokinetics and enhance tumor uptake of radioligands, including prostate-specific membrane antigen (PSMA) targeting agents. The goal of this study is to develop an optimal Evans blue-modified radiotherapeutic agent that could maximize the absolute tumor uptake and tumor absorbed dose thus the therapeutic efficacy to allow treatment of tumors even with moderate level of PSMA expression. METHODS: [177Lu]Lu-LNC1003 was synthesized based on PSMA-targeting agent and Evans blue. Binding affinity and PSMA targeting specificity were verified through cell uptake and competition binding assay in 22Rv1 tumor model that has moderate level of PSMA expression. SPECT/CT imaging and biodistribution studies in 22Rv1 tumor-bearing mice were performed to evaluate the preclinical pharmacokinetics. Radioligand therapy studies were conducted to systematically assess the therapeutic effect of [177Lu]Lu-LNC1003. RESULTS: LNC1003 showed high binding affinity (IC50 = 10.77 nM) to PSMA in vitro, which was comparable with that of PSMA-617 (IC50 = 27.49 nM) and EB-PSMA-617 (IC50 = 7.91 nM). SPECT imaging of [177Lu]Lu-LNC1003 demonstrated significantly improved tumor uptake and retention as compared with [177Lu]Lu-EB-PSMA and [177Lu]Lu-PSMA-617, making it suitable for prostate cancer therapy. Biodistribution studies further confirmed the remarkably higher tumor uptake of [177Lu]Lu-LNC1003 (138.87 ± 26.53%ID/g) over [177Lu]Lu-EB-PSMA-617 (29.89 ± 8.86%ID/g) and [177Lu]Lu-PSMA-617 (4.28 ± 0.25%ID/g) at 24 h post-injection. Targeted radioligand therapy results showed noteworthy inhibition of 22Rv1 tumor growth after administration of a single dose of 18.5 MBq [177Lu]Lu-LNC1003. There was no obvious antitumor effect after [177Lu]Lu-PSMA-617 treatment under the same condition. CONCLUSION: In this study, [177Lu]Lu-LNC1003 was successfully synthesized with high radiochemical purity and stability. High binding affinity and PSMA targeting specificity were identified in vitro and in vivo. With greatly enhanced tumor uptake and retention, [177Lu]Lu-LNC1003 has the potential to improve therapeutic efficacy using significantly lower dosages and less cycles of 177Lu that promises clinical translation to treat prostate cancer with various levels of PSMA expression.


Asunto(s)
Glutamato Carboxipeptidasa II , Neoplasias de la Próstata , Masculino , Humanos , Animales , Ratones , Distribución Tisular , Azul de Evans/uso terapéutico , Glutamato Carboxipeptidasa II/metabolismo , Antígenos de Superficie/metabolismo , Neoplasias de la Próstata/metabolismo , Radiofármacos/farmacocinética , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único/métodos , Línea Celular Tumoral , Lutecio/uso terapéutico , Lutecio/farmacocinética
20.
Proc Natl Acad Sci U S A ; 117(41): 25434-25444, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-32978301

RESUMEN

With rapid economic growth and urbanization, self-sufficiency in crop production has become central to China's agriculture policy. Accurate crop production statistics are essential for research, monitoring, and planning. Although researchers agree that China's statistical authority has considerably modernized over time, China's economic statistics have still been viewed as unreliable and often overstated to meet growth targets at different administrative levels. Recent increases in crop production reported by national statistics have also come under increasing scrutiny. This paper investigates crop production data quality from a planetary boundary perspective-comparing net primary production (NPP) harvested obtained from national statistics with satellite-driven NPP estimates that are supported by detailed observation of land cover, combined with observations on physical factors that limit plant growth. This approach provides a powerful means to check the plausibility of China's grain production statistics at different administrative levels that can generate insights about their discrepancies and can contribute to improved crop production measurements. We find some evidence of potential misreporting problems from the lower administration level where the risk of manipulation of statistics is higher. We also find problems from provincial-level major grain producers. These values can also affect the national totals. Although the numbers are affected by large uncertainties, we find that improving the spatial resolution of key agricultural parameters can greatly improve the reliability of the indicator that in turn can help improve data quality. More reliable production data will be vital for relevant research and provide better insights into food security problems, the carbon cycle, and sustainable development.


Asunto(s)
Agricultura/economía , Producción de Cultivos/estadística & datos numéricos , Productos Agrícolas/economía , China , Abastecimiento de Alimentos , Humanos , Tecnología de Sensores Remotos
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