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1.
Development ; 150(20)2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37039060

RESUMEN

The utilization of reduced plant height genes Rht-B1b and Rht-D1b, encoding homeologous DELLA proteins, led to the wheat Green Revolution (GR). However, the specific functions of GR genes in yield determination and the underlying regulatory mechanisms remained unknown. Here, we validated that Rht-B1b, as a representative of GR genes, affects plant architecture and yield component traits. Upregulation of Rht-B1b reduced plant height, leaf size and grain weight, but increased tiller number, tiller angle, spike number per unit area, and grain number per spike. Dynamic investigations showed that Rht-B1b increased spike number by improving tillering initiation rather than outgrowth, and enhanced grain number by promoting floret fertility. Rht-B1b reduced plant height by reducing cell size in the internodes, and reduced grain size or weight by decreasing cell number in the pericarp. Transcriptome analyses uncovered that Rht-B1b regulates many homologs of previously reported key genes for given traits and several putative integrators for different traits. These findings specify the pleiotropic functions of Rht-B1b in improving yield and provide new insights into the regulatory mechanisms underlying plant morphogenesis and yield formation.


Asunto(s)
Genes de Plantas , Triticum , Alelos , Fenotipo , Grano Comestible/metabolismo , Desarrollo de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Plant Biotechnol J ; 22(6): 1552-1565, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38184782

RESUMEN

The strawberry genus, Fragaria, exhibits a wide range of sexual systems and natural ploidy variation. Nearly, all polyploid strawberry species exhibit separate sexes (dioecy). Research has identified the sex-determining sequences as roughly conserved but with repeatedly changed genomic locations across octoploid strawberries. However, it remains unclear whether tetraploid wild strawberries evolved dioecy independently or shared a common origin with octoploid strawberries. In this study, we investigated the sex determinants of F. moupinensis, a dioecious plant with heterogametic females (ZW). Utilizing a combination of haplotype-resolved genome sequencing of the female F. moupinensis, k-mer-based and coverage-based genome-wide association studies (GWAS), and transcriptomic analysis, we discovered a non-recombining, approximately 33.6 kb W-specific region on chromosome 2a. Within this region, only one candidate sex-determining gene (FmoAFT) was identified. Furthermore, an extensive resequencing of the entire Fragaria genus indicated that the W-specific region displays conservative female specificity across all tetraploid species. This observation suggests that dioecy evolved independently in tetraploid and octoploid strawberries. Moreover, employing virus-induced gene silencing (VIGS), we knocked down the expression of the FmoAFT homologue transcript in cultivated strawberries, revealing its potential role in promoting female functions during early carpel development. We also applied DNA affinity purification sequencing (DAP-seq) and yeast one-hybrid assays to identify potential direct targets of FmoAFT. These insights shed new light on the genetic basis and evolutionary history of sex determination in strawberries, thereby facilitating the formulation of strategies to manipulate sex determination in breeding programs.


Asunto(s)
Fragaria , Genoma de Planta , Estudio de Asociación del Genoma Completo , Tetraploidía , Fragaria/genética , Fragaria/crecimiento & desarrollo , Genoma de Planta/genética , Cromosomas de las Plantas/genética
3.
Opt Lett ; 49(8): 1892-1895, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38621032

RESUMEN

We experimentally demonstrate the highly-efficient nonlocal erasing and writing of ferroelectric domains using a femtosecond laser in lithium niobate. Based on the induction of a focused infrared femtosecond laser without any relative displacement or additional treatment, the original multiple ferroelectric domains can be either erased (erasing operation) or elongated (writing operation) simultaneously in the crystal, depending on the laser focusing depth and the laser pulse energy. In the erasing operation, the original multiple ferroelectric domains can be cleared completely by just one laser induction, while in the writing operation, the average length of the ferroelectric domains can be elongated up to 235 µm by three laser inductions. A model has been proposed in which a thermoelectric field and a space charge field are used cooperatively to successfully explain the mechanism of nonlocal erasing and writing. This method greatly improves the efficiency and flexibility of tailoring ferroelectric domain structures, paving the way to large-scale all-optical industrial production for nonlinear photonic crystals and nonvolatile ferroelectric domain wall memories.

4.
Opt Lett ; 49(4): 1097-1100, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359262

RESUMEN

We experimentally extend the nonlinear Gaussian to flat-top beam shaping from one to two dimensions through a three-dimensional nonlinear photonic crystal. Employing a near-infrared femtosecond laser, we induce a modification inside lithium niobate to achieve a second-order nonlinear optical coefficient modulation in three dimensions. The flat-topped truncation of wavefront has been adjusted in a mutual perpendicular coordinate separately. Among the generated flat-topped beams, the optimal flatness is 97.1%, and the nonlinear conversion efficiency is 10-2 at the peak power of 37 kW with the interaction length of 630 µm. By adding an extra dimension, our work simultaneously enables full-wavefront flat-top distribution and nonlinear frequency conversion.

5.
BMC Cancer ; 24(1): 460, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609892

RESUMEN

BACKGROUND: To predict pathological complete response (pCR) in patients receiving neoadjuvant immunochemotherapy (nICT) for esophageal squamous cell carcinoma (ESCC), we explored the factors that influence pCR after nICT and established a combined nomogram model. METHODS: We retrospectively included 164 ESCC patients treated with nICT. The radiomics signature and hematology model were constructed utilizing least absolute shrinkage and selection operator (LASSO) regression, and the radiomics score (radScore) and hematology score (hemScore) were determined for each patient. Using the radScore, hemScore, and independent influencing factors obtained through univariate and multivariate analyses, a combined nomogram was established. The consistency and prediction ability of the nomogram were assessed utilizing calibration curve and the area under the receiver operating factor curve (AUC), and the clinical benefits were assessed utilizing decision curve analysis (DCA). RESULTS: We constructed three predictive models.The AUC values of the radiomics signature and hematology model reached 0.874 (95% CI: 0.819-0.928) and 0.772 (95% CI: 0.699-0.845), respectively. Tumor length, cN stage, the radScore, and the hemScore were found to be independent factors influencing pCR according to univariate and multivariate analyses (P < 0.05). A combined nomogram was constructed from these factors, and AUC reached 0.934 (95% CI: 0.896-0.972). DCA demonstrated that the clinical benefits brought by the nomogram for patients across an extensive range were greater than those of other individual models. CONCLUSIONS: By combining CT radiomics, hematological factors, and clinicopathological characteristics before treatment, we developed a nomogram model that effectively predicted whether ESCC patients would achieve pCR after nICT, thus identifying patients who are sensitive to nICT and assisting in clinical treatment decision-making.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Terapia Neoadyuvante , Carcinoma de Células Escamosas de Esófago/diagnóstico por imagen , Carcinoma de Células Escamosas de Esófago/terapia , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/tratamiento farmacológico , Nomogramas , Radiómica , Estudios Retrospectivos
6.
J Magn Reson Imaging ; 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38456745

RESUMEN

BACKGROUND: The human epidermal growth factor receptor 2 (HER2) has recently emerged as hotspot in targeted therapy for urothelial bladder cancer (UBC). The HER2 status is mainly identified by immunohistochemistry (IHC), preoperative and noninvasive methods for determining HER2 status in UBC remain in searching. PURPOSES: To investigate whether radiomics features extracted from MRI using machine learning algorithms can noninvasively evaluate the HER2 status in UBC. STUDY TYPE: Retrospective. POPULATION: One hundred ninety-five patients (age: 68.7 ± 10.5 years) with 14.3% females from January 2019 to May 2023 were divided into training (N = 156) and validation (N = 39) cohorts, and 43 patients (age: 67.1 ± 13.1 years) with 13.9% females from June 2023 to January 2024 constituted the test cohort (N = 43). FIELD STRENGTH/SEQUENCE: 3 T, T2-weighted imaging (turbo spin-echo), diffusion-weighted imaging (breathing-free spin echo). ASSESSMENT: The HER2 status were assessed by IHC. Radiomics features were extracted from MRI images. Pearson correlation coefficient and the least absolute shrinkage and selection operator (LASSO) were applied for feature selection, and six machine learning models were established with optimal features to identify the HER2 status in UBC. STATISTICAL TESTS: Mann-Whitney U-test, chi-square test, LASSO algorithm, receiver operating characteristic analysis, and DeLong test. RESULTS: Three thousand forty-five radiomics features were extracted from each lesion, and 22 features were retained for analysis. The Support Vector Machine model demonstrated the best performance, with an AUC of 0.929 (95% CI: 0.888-0.970) and accuracy of 0.859 in the training cohort, AUC of 0.886 (95% CI: 0.780-0.993) and accuracy of 0.846 in the validation cohort, and AUC of 0.712 (95% CI: 0.535-0.889) and accuracy of 0.744 in the test cohort. DATA CONCLUSION: MRI-based radiomics features combining machine learning algorithm provide a promising approach to assess HER2 status in UBC noninvasively and preoperatively. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.

7.
J Magn Reson Imaging ; 59(4): 1179-1190, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37602726

RESUMEN

BACKGROUND: Vesical Imaging-Reporting and Data System (VI-RADS) is widely used to assess the muscle-invasive status of bladder cancer. However, the current classification efficacy of VI-RASD 2 tumors of stalk is unsatisfactory. PURPOSE: To develop a nomogram to assess muscle-invasive bladder cancer (MIBC) in VI-RADS 2 tumors with stalk. STUDY TYPE: Retrospective. POPULATION: A total of 186 patients (age: 67.8 ± 12.7 years) with 15.1% females, divided randomly into a training cohort (N = 130) and validation cohort (N = 56). FIELD STRENGTH/SEQUENCE: 3-T, T2-weighted imaging (turbo spin-echo), diffusion-weighted imaging (breathing-free spin-echo), and dynamic contrast-enhanced imaging (gradient-echo). ASSESSMENT: Twenty-one MRI features of tumors and stalks were developed from training cohort. The mean apparent diffusion coefficient (ADC) values of the tumor, stalk, and psoas muscles were calculated from the three circular regions of interest. The normalized T value = mean ADC tumor mean ADC muscle . The normalized ST value = mean ADC stalk mean ADC tumor . Three readers assessed the morphology of tumors and stalks. STATISTICAL TESTS: The final features of nomogram were selected by univariable logistic and the least absolute shrinkage and selection operator (LASSO) regression. The performance of the nomogram was assessed by the receiver operating characteristic (ROC) curve, calibration, and decision curve analysis. RESULTS: In VI-RADS 2 tumors with stalk, tumor size over 3 cm, increased stalk width, stalk morphology, decreased normalized T value, and increased normalized ST value were selected as the risk factors for MIBC. The AUC, accuracy, sensitivity, and specificity of the nomogram to assess MIBC were 0.969 (95% CI: 0.941-0.997), 92.3%, 94.1%, and 92.0% in training cohort and 0.940 (95% CI: 0.859-1.000), 89.3%, 75.0%, and 91.7% in validation cohort. DATA CONCLUSION: This study constructed a nomogram for preoperative assessment of MIBC and modifying the current VI-RADS. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Nomogramas , Neoplasias de la Vejiga Urinaria , Femenino , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Masculino , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Neoplasias de la Vejiga Urinaria/patología , Músculos/patología
8.
Theor Appl Genet ; 137(7): 148, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38836887

RESUMEN

KEY MESSAGE: Three stable QTL for grain zinc concentration were identified in wheat landrace Chinese Spring. Favorable alleles were more frequent in landraces than in modern wheat cultivars. Wheat is a major source of dietary energy for the growing world population. Developing cultivars with enriched zinc and iron can potentially alleviate human micronutrient deficiency. In this study, a recombinant inbred line (RIL) population with 245 lines derived from cross Zhou 8425B/Chinese Spring was used to detect quantitative trait loci (QTL) for grain zinc concentration (GZnC) and grain iron concentration (GFeC) across four environments. Three stable QTL for GZnC with all favorable alleles from Chinese Spring were identified on chromosomes 3BL, 5AL, and 5BL. These QTL explaining maxima of 8.7%, 5.8%, and 7.1% of phenotypic variances were validated in 125 resequenced wheat accessions encompassing both landraces and modern cultivars using six kompetitive allele specific PCR (KASP) assays. The frequencies of favorable alleles for QGZnCzc.caas-3BL, QGZnCzc.caas-5AL and QGZnCzc.caas-5BL were higher in landraces (90.4%, 68.0%, and 100.0%, respectively) compared to modern cultivars (45.9%, 35.4%, and 40.9%), suggesting they were not selected in breeding programs. Candidate gene association studies on GZnC in the cultivar panel further delimited the QTL into 8.5 Mb, 4.1 Mb, and 47.8 Mb regions containing 46, 4, and 199 candidate genes, respectively. The 5BL QTL located in a region where recombination was suppressed. Two stable and three less stable QTL for GFeC with favorable alleles also from Chinese Spring were identified on chromosomes 4BS (Rht-B1a), 4DS (Rht-D1a), 1DS, 3AS, and 6DS. This study sheds light on the genetic basis of GZnC and GFeC in Chinese Spring and provides useful molecular markers for wheat biofortification.


Asunto(s)
Alelos , Mapeo Cromosómico , Hierro , Fenotipo , Sitios de Carácter Cuantitativo , Triticum , Zinc , Triticum/genética , Zinc/metabolismo , Hierro/metabolismo , Grano Comestible/genética , Cromosomas de las Plantas/genética , Semillas/genética , Semillas/química , Genotipo
9.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34697247

RESUMEN

Strawberry (Fragaria spp.) has emerged as a model system for various fundamental and applied research in recent years. In total, the genomes of five different species have been sequenced over the past 10 y. Here, we report chromosome-scale reference genomes for five strawberry species, including three newly sequenced species' genomes, and genome resequencing data for 128 additional accessions to estimate the genetic diversity, structure, and demographic history of key Fragaria species. Our analyses obtained fully resolved and strongly supported phylogenies and divergence times for most diploid strawberry species. These analyses also uncovered a new diploid species (Fragaria emeiensis Jia J. Lei). Finally, we constructed a pan-genome for Fragaria and examined the evolutionary dynamics of gene families. Notably, we identified multiple independent single base mutations of the MYB10 gene associated with white pigmented fruit shared by different strawberry species. These reference genomes and datasets, combined with our phylogenetic estimates, should serve as a powerful comparative genomic platform and resource for future studies in strawberry.


Asunto(s)
Evolución Biológica , Fragaria/genética , Genoma de Planta , Fragaria/clasificación , Variación Genética , Filogeografía , Pigmentación/genética , Selección Genética , Secuenciación Completa del Genoma
10.
Nano Lett ; 23(23): 11323-11329, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38019659

RESUMEN

The orbital angular momentum (OAM) generation as well as its associated orbital torque is currently a matter of great interest in spin-orbitronics and is receiving increasing attention. In particular, recent theoretical work predicts that the oxidized light metal Cu can serve as an efficient OAM generator through its surface orbital Rashba effect. Here, for the first time, the crucial current-induced magnetic-field-free in-plane magnetization reversal is experimentally demonstrated in CoFeB/CuOx bilayers without any heavy elements. We show that the critical current density can be comparable to that of strong spin-orbit coupling systems with heavy metals (Pt and Ta) and that the magnetization reversal mechanism is governed by coherent rotation in the grains through the second-harmonic and magneto-optical Kerr effect measurements. Our results indicate that light metal oxides can play an equally important role as heavy metals in magnetization reversal, broadening the choice of materials for engineering spintronic devices.

11.
J Sci Food Agric ; 104(3): 1645-1655, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37850306

RESUMEN

BACKGROUND: The interaction between food allergens and plant polyphenols has become a safe and effective management strategy to prevent food allergies. Ovalbumin (OVA) is the most abundant allergen in egg whites. Resveratrol (RES) is a plant polyphenol that is abundant in red grapes, berries, and peanuts, and has an anti-allergic effect on allergy-related immune cells. However, there is little information about the effect of RES on the allergenicity of OVA. In this study, the effect of RES on the allergenicity of OVA was investigated. RESULTS: Molecular docking and spectroscopic studies indicated that the addition of RES changed the structure of OVA. The digestion and transfer rate of OVA-RES were effectively improved with an in vitro gastrointestinal digestion model and Caco-2 cell model, especially when the molar ratio of OVA-RES was 1:20. Meanwhile, the KU812 cell degranulation assay proved that the potential allergenicity was remarkably decreased while the molar ratios of OVA-RES were increased to 1:20. Furthermore, hydrogen bonds and van der Waals forces were the dominating forces to stabilize the OVA-RES complexes. CONCLUSION: All the findings demonstrated that the potential allergenicity of OVA was reduced when interacting with RES, and RES can be a potential food material for preparing a hypoallergenic protein, especially for egg allergy. © 2023 Society of Chemical Industry.


Asunto(s)
Alérgenos , Hipersensibilidad a los Alimentos , Humanos , Ovalbúmina/química , Resveratrol , Simulación del Acoplamiento Molecular , Células CACO-2 , Inmunoglobulina E , Hipersensibilidad a los Alimentos/prevención & control
12.
BMC Genomics ; 24(1): 235, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37138231

RESUMEN

BACKGROUND: DNA hypermethylation at promoter CpG islands (CGIs) is a hallmark of cancers and could lead to dysregulation of gene expression in the development of cancers, however, its dynamics and regulatory mechanisms remain elusive. Bivalent genes, that direct development and differentiation of stem cells, are found to be frequent targets of hypermethylation in cancers. RESULTS: Here we performed comprehensive analysis across multiple cancer types and identified that the decrease in H3K4me1 levels coincides with DNA hypermethylation at the bivalent promoter CGIs during tumorigenesis. Removal of DNA hypermethylation leads to increment of H3K4me1 at promoter CGIs with preference for bivalent genes. Nevertheless, the alteration of H3K4me1 by overexpressing or knockout LSD1, the demethylase of H3K4, doesn't change the level or pattern of DNA methylation. Moreover, LSD1 was found to regulate the expression of a bivalent gene OVOL2 to promote tumorigenesis. Knockdown of OVOL2 in LSD1 knockout HCT116 cells restored the cancer cell phenotype. CONCLUSION: In summary, our work identified a universal indicator that can pre-mark DNA hypermethylation in cancer cells, and dissected the interplay between H3K4me1 and DNA hypermethylation in detail. Current study also reveals a novel mechanism underlying the oncogenic role of LSD1, providing clues for cancer therapies.


Asunto(s)
Metilación de ADN , Histonas , Humanos , Histonas/metabolismo , Código de Histonas , Carcinogénesis/genética , Histona Demetilasas/genética , Histona Demetilasas/metabolismo , ADN/metabolismo , Islas de CpG , Factores de Transcripción/metabolismo
13.
Small ; 19(2): e2205341, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36399645

RESUMEN

Chloramphenicol (CAP) has long been used extensively in agriculture and is severely toxic to the biological environment. Microwave catalysis appears a promising method for soil remediation due to its fast and effective heat transfer, but it is challenging to prepare catalysts with good electromagnetic wave absorption and robust catalytic activity. In this study, atomically dispersed Fe on three-dimensional N-doped carbon supports (3D Fe-NC) is firstly used for microwave remediation of soil. Thanks to the synergistic effect of microwave "hot spots" and reactive oxygen species (•OH, •O2 - ), 3D Fe-NC can completely remove 99.9% of CAP in 5 min. The removal rate constant is nearly twice that of commercial activated carbon. Significantly, the germination rate of lettuce seeds in microwave-repaired soil contaminated by CAP reaches 70%. This work demonstrates the application of Fe single-atom catalyst in microwave remediation of contaminated soil, providing a novel insight for agricultural soil remediation.


Asunto(s)
Cloranfenicol , Contaminantes del Suelo , Microondas , Suelo , Catálisis
14.
Small ; 19(7): e2205604, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36494094

RESUMEN

The charge recombination resulting from bulk defects and interfacial energy level mismatch hinders the improvement of the power conversion efficiency (PCE) and stability of carbon-based inorganic perovskite solar cells (C-IPSCs). Herein, a series of small molecules including ethylenediaminetetraacetic acid (EDTA) and its derivatives (EDTA-Na and EDTA-K) are studied to functionalize the zinc oxide (ZnO) interlayers at the SnO2 /CsPbI2 Br buried interface to boost the photovoltaic performance of low-temperature C-IPSCs. This strategy can simultaneously passivate defects in ZnO and perovskite films, adjust interfacial energy level alignment, and release interfacial tensile stress, thereby improving interfacial contact, inhibiting ion migration, alleviating charge recombination, and promoting electron transport. As a result, a maximum PCE of 13.94% with a negligible hysteresis effect is obtained, which is one of the best results reported for low-temperature CsPbI2 Br C-IPSCs so far. Moreover, the optimized devices without encapsulation demonstrate greatly improved operational stability.

15.
Opt Lett ; 48(3): 566-569, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723532

RESUMEN

We experimentally demonstrate to drive domain growth in lithium niobate crystal by using a focused infrared femtosecond laser without relative displacement or any additional treatment. The physical process has four stages: modified domain generation; thermoelectric field formation; domain inversion; and domain growth. The length of domain growth depends on drive energy (pulse energy) and drive time (number of pulses), up to 155 µm. We use this approach to rapidly fabricate two-dimensional period-inverted domain structures and perform frequency-doubling conversion based on quasi-phase-matching. Laser-driven domain growth delivers an efficient manufacturing route for tailored functional materials.

16.
Phys Rev Lett ; 130(21): 215001, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37295115

RESUMEN

Curved plasma channels have been proposed to guide intense lasers for various applications, such as x-ray laser emission, compact synchrotron radiation, and multistage laser wakefield acceleration [e.g. J. Luo et al., Phys. Rev. Lett. 120, 154801 (2018)PRLTAO0031-900710.1103/PhysRevLett.120.154801]. Here, a carefully designed experiment shows evidences of intense laser guidance and wakefield acceleration in a centimeter-scale curved plasma channel. Both experiments and simulations indicate that when the channel curvature radius is gradually increased and the laser incidence offset is optimized, the transverse oscillation of the laser beam can be mitigated, and the stably guided laser pulse excites wakefields and accelerates electrons along the curved plasma channel to a maximum energy of 0.7 GeV. Our results also show that such a channel exhibits good potential for seamless multistage laser wakefield acceleration.


Asunto(s)
Aceleración , Electrones , Frecuencia Cardíaca , Rayos Láser , Plasma
17.
Chemistry ; 29(36): e202300914, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37078552

RESUMEN

Exploration of organometallic metallacycles has led to the development of various polycyclic compounds with fascinating structures, which could be used as functional materials. In this work, a new rhenanaphthalene isomer was isolated from the reaction of ReH5 (PMe2 Ph)3 with o-ethynylphenyl alkyne in the presence of excess HCl. Its structure was then identified using the single-crystal X-ray diffraction and NMR spectroscopy. DFT studies suggest that its formation involves two protonation reactions and two migration reactions. This new rhenanaphthalene isomer enriches the family of metallacycles.

18.
J Magn Reson Imaging ; 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37902432

RESUMEN

BACKGROUND: The relationship between tumor and muscle layer in the vesical imaging-reporting and data system (VI-RADS) 3 is ambiguous, and there is a lack of preoperative and non-invasive procedures to detect muscle invasion in VI-RADS 3. PURPOSE: To develop a nomogram based on MRI features for detecting muscle invasion in VI-RADS 3. STUDY TYPE: Retrospective. POPULATION: 235 cases (Age: 67.5 ± 11.5 years) with 11.9% females were randomly divided into a training cohort (n = 164) and a validation cohort (n = 71). FIELD STRENGTH/SEQUENCE: 3T, T2-weighted imaging (turbo spin-echo), diffusion-weighted imaging (breathing-free spin echo), and dynamic contrast-enhanced imaging (gradient echo). ASSESSMENT: 3 features were selected from the training cohort, including tumor contact length greater than maximum tumor diameter (TCL > Dmax), flat tumor morphology, and lower standard deviation of apparent diffusion coefficient (ADCSD ). Three readers assessed VI-RADS scores and the tumor morphology. STATISTICAL TESTS: Interobserver agreement was assessed by Kappa analysis. Features for final analysis were selected by logistic regression. The performance of the nomogram was evaluated by the receiver operating characteristic curve, decision curve analysis, and calibration curve. RESULTS: TCL > Dmax, flat morphology, and lower ADCSD were the independent risk factors for muscle invasive in VI-RADS 3. The AUCs, accuracy, sensitivity, and specificity of the nomogram 1 composed of three features for detecting muscle invasion were 0.852 (95% CI: 0.793-0.912), 0.756, 0.917, and 0.663 in the training cohort, and 0.885 (95% CI: 0.801-0.969), 0.817, 0.900, and 0.784 in the validation cohort. The nomogram 2 without ADCSD has nearly the same performance as the nomogram 1. DATA CONCLUSION: Nomogram can be an efficient tool for preoperative detection of muscle invasion in VI-RADS 3. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

19.
J Magn Reson Imaging ; 2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38153874

RESUMEN

BACKGROUND: Vesical Imaging-Reporting and Data System (VI-RADS) has been developed for assessing bladder cancer from multiparametric (mp) MRI but its performance in diagnosing muscle-invasive bladder cancer (MIBC) is suboptimal. PURPOSE: To investigate associations between normalized apparent diffusion coefficient (NADC) and clinicopathological characteristics and to determine whether the inclusion of NADC can improve the performance of VI-RADS in diagnosing MIBC. STUDY TYPE: Retrospective. POPULATION: Two hundred seventy-five patients with pathologically confirmed bladder cancer (101 MIBC and 174 non-MIBC [NMIBC]) underwent preoperative mpMRI (233 male, 42 female). FIELD STRENGTH/SEQUENCE: 3-T, T2-weighted imaging (turbo spin-echo), diffusion-weighted imaging (free-breathing spin-echo), and dynamic contrast-enhanced imaging (gradient-echo). ASSESSMENT: NADC was the mean ADC of tumor divided by that of the iliopsoas muscles in trans caput femoris plane. Associations between NADC and clinicopathological characteristics were evaluated. Models were established for differentiating MIBC and NMIBC: VI-RADS model; VN model (VI-RADS and NADC), Images model (significant variables from imaging associated with MIBC), LN model (Images model without NADC), and Full model (all significant variables associated with MIBC). STATISTICAL TESTS: Variables for model development were based on logistic regression. Models were evaluated by receiver operating characteristic (ROC) curve. Comparison of the area under the curves (AUCs) for the models used DeLong's test. A P value <0.05 was considered statistically significant. RESULTS: NADC was significantly lower in lesions with diameter ≥ 3 cm, MIBC, histological high grade, lymph node metastasis, and lymphovascular invasion. Compared with VI-RADS model, the AUCs for VN model (VI-RADS score and NADC), Images model (VI-RADS score, NADC and tumor size) and Full model (VI-RADS score, NADC, tumor size and histological grade) were significantly higher. No significant differences were observed between the AUCs for VN model and Images model (P = 0.051). DATA CONCLUSION: NADC reflects information about the aggressiveness of bladder cancer. Combining VI-RADS with NADC can improve performance in diagnosing MIBC. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

20.
Theor Appl Genet ; 136(6): 142, 2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37247049

RESUMEN

KEY MESSAGE: Adult-plant stripe rust resistance gene Yr86 in Chinese wheat cultivar Zhongmai 895 was mapped to the physical interval 710.2-713.2 Mb on the long arm of chromosome 2A. Adult-plant resistance to stripe rust is generally more durable than all-stage resistance. Chinese wheat cultivar Zhongmai 895 showed stable stripe rust resistance at the adult-plant stage. To map the genetic loci underlying its resistance, 171 doubled haploid (DH) lines from a Yangmai 16/Zhongmai 895 cross were genotyped with the wheat 660 K SNP chip. Disease severities of the DH population and parents were assessed in four environments. A major QTL designated QYryz.caas-2AL was mapped to interval 703.7-715.3 Mb on the long arm of chromosome 2A using both chip-based and KASP (kompetitive allele-specific PCR) marker-based methods, explaining 31.5 to 54.1% of the phenotypic variances. The QTL was further validated in an F2 population of cross Emai 580/Zhongmai 895 with 459 plants and a panel of 240 wheat cultivars using KASP markers. Three reliable KASP markers predicted a low frequency (7.2-10.5%) of QYryz.caas-2AL in the test panel and remapped the gene to the physical interval 710.2-713.2 Mb. Based on different physical positions or genetic effects from known genes or QTL on chromosome arm 2AL, the gene was predicted to be a new one for adult-plant stripe rust resistance and was named Yr86. Twenty KASP markers linked to Yr86 were developed in this study based on wheat 660 K SNP array and genome re-sequencing. Three of them are significantly associated with stripe rust resistance in natural population. These markers should be useful for marker-assisted selection and also provide a starting point for fine mapping and map-based cloning of the new resistance gene.


Asunto(s)
Basidiomycota , Sitios de Carácter Cuantitativo , Triticum/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Polimorfismo de Nucleótido Simple
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