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1.
J Magn Reson Imaging ; 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38822655

RESUMEN

BACKGROUND: Ki-67 and human epidermal growth factor receptor 2 (HER2) are known oncogenes involved in bladder cancer (BCa) patient risk stratification. Preoperative assessment of their expression level can assist in clinical treatment decision-making. Recently, amide proton transfer-weighted (APTw) MRI has shown promising potential in the diagnosis of several malignancies. However, few studies reported the value of APTw imaging in evaluating Ki-67 and HER2 status of BCa. PURPOSE: To investigate the feasibility of APTw MRI in assessing the aggressive and proliferative potential regarding the expression levels of Ki-67 and HER2 in BCa. STUDY TYPE: Retrospective. SUBJECTS: 114 patients (mean age, 64.78 ± 11.93 [SD] years; 97 men) were studied. FIELD STRENGTH/SEQUENCE: APTw MRI acquired by a three-dimensional fast-spin-echo sequence at 3.0 T MRI system. ASSESSMENT: Patient pathologic findings, included histologic grade and the expression status of Ki-67 and HER2, were reviewed by one uropathologist. The APTw values of BCa were independently measured by two radiologists and were compared between high-/low-tumor grade group, high-/low-Ki-67 expression group, and high-/low-HER2 expression group. STATISTICAL TESTS: The interclass correlation coefficient, independent sample t-test, Mann-Whitney U test, Spearman's rank correlation, and receiver operating characteristic curve (ROC) analysis were used. P < 0.05 was considered statistically significant. RESULTS: Significantly higher APTw values were found in high-grade BCa patients (7.72% vs. 4.29%, P < 0.001), high-Ki-67 expression BCa patients (8.40% vs. 3.25%, P < 0.001) and HER2 positive BCa patients (8.24% vs. 5.40%, P = 0.001). APTw values were positively correlated with Ki-67 (r = 0.769) and HER2 (r = 0. 356) expression status. The area under the ROC curve of the APTw values for detecting Ki-67 and HER2 expression status were 0.883 (95% CI: 0.790-0.945) and 0.713 (95% CI: 0.592-0.816), respectively. DATA CONCLUSIONS: APTw MRI is a potential method to assess the biological and proliferation potential of BCa. TECHNICAL EFFICACY: Stage 2.

2.
Adv Sci (Weinh) ; : e2403059, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840438

RESUMEN

Plants have evolved diverse defense mechanisms encompassing physical and chemical barriers. Cotton pigment glands are known for containing various defense metabolites, but the precise regulation of gland size to modulate defense compound levels remains enigmatic. Here, it is discovered that the VQ domain-containing protein JAVL negatively regulates pigment gland size and the biosynthesis of defense compounds, while the MYC2-like transcription factor GoPGF has the opposite effect. Notably, GoPGF directly activates the expression of JAVL, whereas JAVL suppresses GoPGF transcription, establishing a negative feedback loop that maintains the expression homeostasis between GoPGF and JAVL. Furthermore, it is observed that JAVL negatively regulates jasmonate levels by inhibiting the expression of jasmonate biosynthetic genes and interacting with GoPGF to attenuate its activation effects, thereby maintaining homeostatic regulation of jasmonate levels. The increased expression ratio of GoPGF to JAVL leads to enlarged pigment glands and elevated jasmonates and defense compounds, enhancing insect and pathogen resistance in cotton. These findings unveil a new mechanism for regulating gland size and secondary metabolites biosynthesis, providing innovative strategies for strengthening plant defense.

3.
Phys Med Biol ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38815617

RESUMEN

Objective Peripheral Vascular Disease (PVD) affects more than 230 million people worldwide and is one of the leading causes of disability among people over age 60. Nowadays, PVD remains largely underdiagnosed and undertreated, and requires the development of tailored diagnostic approaches. We present the full design of the Dynamic Extremity SPECT (DE-SPECT) system, the first organ-dedicated SPECT system for lower extremity imaging, based on 1-cm thick Cadmium Zinc Telluride (CZT) spectrometers and a dynamic dual field-of-view (FOV) synthetic compound-eye collimator. Approach The proposed DE-SPECT detection system consists of 48 1-cm thick 3D-position-sensitive CZT spectrometers arranged in a partial ring of 59 cm in diameter in a checkerboard pattern. The detection system is coupled with a compact dynamic synthetic compound-eye (SCE) collimator that allows the user to select between two different FOVs at any time during an imaging study: a wide-FOV (28-cm diameter) configuration for dual-leg or scout imaging or a high-resolution and high-sensitivity (HR-HS) FOV (16-cm diameter) for single-leg or focused imaging. Main Results The preliminary experimental data show that the CZT spectrometer achieves a 3D intrinsic spatial resolution of <0.75 mm FWHM and an excellent energy resolution over a broad energy range (2.6 keV FWHM at 218 keV, 3.3 keV at 440 keV). From simulations, the wide-FOV configuration offers a 0.034% averaged sensitivity at 140 keV and <8 mm spatial resolution, whereas the HR-HS configuration presents a peak central sensitivity of 0.07% at 140 keV and a ~5 mm spatial resolution. The dynamic SCE collimator enables the capability to perform joint reconstructions that would ensure an overall improvement in imaging performance. Significance The DE-SPECT system is a stationary and high-performance SPECT system that offers an excellent spectroscopic performance with a unique computer-controlled dual-FOV imaging capability, and a relatively high sensitivity for multi-tracer and multi-functional SPECT imaging of the extremities.

4.
IEEE Trans Med Imaging ; 43(5): 1782-1791, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38696285

RESUMEN

The advent of metal-based drugs and metal nanoparticles as therapeutic agents in anti-tumor treatment has motivated the advancement of X-ray fluorescence computed tomography (XFCT) techniques. An XFCT imaging modality can detect, quantify, and image the biodistribution of metal elements using the X-ray fluorescence signal emitted upon X-ray irradiation. However, the majority of XFCT imaging systems and instrumentation developed so far rely on a single or a small number of detectors. This work introduces the first full-ring benchtop X-ray fluorescence emission tomography (XFET) system equipped with 24 solid-state detectors arranged in a hexagonal geometry and a 96-pinhole compound-eye collimator. We experimentally demonstrate the system's sensitivity and its capability of multi-element detection and quantification by performing imaging studies on an animal-sized phantom. In our preliminary studies, the phantom was irradiated with a pencil beam of X-rays produced using a low-powered polychromatic X-ray source (90kVp and 60W max power). This investigation shows a significant enhancement in the detection limit of gadolinium to as low as 0.1 mg/mL concentration. The results also illustrate the unique capabilities of the XFET system to simultaneously determine the spatial distribution and accurately quantify the concentrations of multiple metal elements.


Asunto(s)
Fantasmas de Imagen , Animales , Espectrometría por Rayos X/métodos , Diseño de Equipo , Procesamiento de Imagen Asistido por Computador/métodos , Ratones
5.
FEBS J ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38567754

RESUMEN

Acute kidney injury (AKI) induced by renal ischemia-reperfusion injury (IRI) has a high morbidity and mortality, representing a worldwide problem. The kidney is an essential organ of metabolism that has high blood perfusion and is the second most mitochondria-rich organ after the heart because of the high ATP demands of its essential functions of nutrient reabsorption, acid-base and electrolyte balance, and hemodynamics. Thus, these energy-intensive cells are particularly vulnerable to mitochondrial dysfunction. As the bulk of glomerular ultrafiltrate reabsorption by proximal tubules occurs via active transport, the mitochondria of proximal tubules must be equipped for detecting and responding to fluctuations in energy availability to guarantee efficient basal metabolism. Any insults to mitochondrial quality control mechanisms may lead to biological disruption, blocking the clearance of damaged mitochondria and resulting in morphological change and tissue dysfunction. Extensive research has shown that mitochondria have pivotal roles in acute kidney disease, so in this article, we discuss the role of mitochondria, their dynamics and mitophagy in renal ischemia-reperfusion injury.

6.
Front Microbiol ; 15: 1385255, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38638906

RESUMEN

Chemical study of the nematicidal biocontrol fungus Pochonia chlamydosporia PC-170 led to discovery of six resorcylic acid lactones (RALs), including three nematicidal glycosylated RALs, monocillin VI glycoside (1), colletogloeolactone A (2) and monocillin II glycoside (3), and three antibacterial non-glycosylated RALs, monocillin VI (4), monocillin IV (5) and monocillin II (6). The planar structure of the new compound monocillin VI glycoside (1) was elucidated using HRESIMS and NMR data, and its monosaccharide configuration was further determined through sugar hydrolysis experiment and GC-MS analysis method. Furthermore, their two biosynthetic-related PKS genes, pchE and pchI, were identified through the gene knockout experiment. The glycosylated RALs 1-3 exhibited nematicidal activity against Meloidogyne incognita, with LC50 values of 94, 152 and 64 µg/mL, respectively, and thus had great potential in the development of new nematicidal natural products to control M. incognita in the future.

7.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38673861

RESUMEN

Plant-parasitic nematodes (PPNs) are among the most serious phytopathogens and cause widespread and serious damage in major crops. In this study, using a genome mining method, we identified nonribosomal peptide synthetase (NRPS)-like enzymes in genomes of plant-parasitic nematodes, which are conserved with two consecutive reducing domains at the N-terminus (A-T-R1-R2) and homologous to fungal NRPS-like ATRR. We experimentally investigated the roles of the NRPS-like enzyme (MiATRR) in nematode (Meloidogyne incognita) parasitism. Heterologous expression of Miatrr in Saccharomyces cerevisiae can overcome the growth inhibition caused by high concentrations of glycine betaine. RT-qPCR detection shows that Miatrr is significantly upregulated at the early parasitic life stage (J2s in plants) of M. incognita. Host-derived Miatrr RNA interference (RNAi) in Arabidopsis thaliana can significantly decrease the number of galls and egg masses of M. incognita, as well as retard development and reduce the body size of the nematode. Although exogenous glycine betaine and choline have no obvious impact on the survival of free-living M. incognita J2s (pre-parasitic J2s), they impact the performance of the nematode in planta, especially in Miatrr-RNAi plants. Following application of exogenous glycine betaine and choline in the rhizosphere soil of A. thaliana, the numbers of galls and egg masses were obviously reduced by glycine betaine but increased by choline. Based on the knowledge about the function of fungal NRPS-like ATRR and the roles of glycine betaine in host plants and nematodes, we suggest that MiATRR is involved in nematode-plant interaction by acting as a glycine betaine reductase, converting glycine betaine to choline. This may be a universal strategy in plant-parasitic nematodes utilizing NRPS-like ATRR to promote their parasitism on host plants.


Asunto(s)
Arabidopsis , Betaína , Péptido Sintasas , Tylenchoidea , Betaína/metabolismo , Animales , Tylenchoidea/metabolismo , Tylenchoidea/genética , Arabidopsis/parasitología , Arabidopsis/metabolismo , Arabidopsis/genética , Péptido Sintasas/metabolismo , Péptido Sintasas/genética , Interacciones Huésped-Parásitos , Enfermedades de las Plantas/parasitología , Proteínas del Helminto/metabolismo , Proteínas del Helminto/genética , Nematodos/metabolismo , Nematodos/genética
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124140, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38479229

RESUMEN

In this paper, we designed and synthesized a two-dimensional fluorescent covalent organic framework (TAPB-DMTP-COF) for the precise determination of H2O content in methanol. The COF was synthesized using two typical monomers by grinding method, which significantly reduced the synthesis time. By adjusting the pH value of the COF suspension to 4.0, the portion of the COF material structure is disrupted, thereby mitigating π-π stacking and resolving the aggregation-caused quenching (ACQ) effect. Consequently, the non-fluorescent TAPB-DMTP-COF exhibited blue-purple fluorescence emission in methanol. At the same time, it is observed that in the presence of H2O, there is a red shift in the maximum fluorescence emission peak of TAPB-DMTP-COF, which correlates with the H2O content within a specific range. Notably, this redshift demonstrates a linear relationship with H2O content from 4% to 80% in methanol. Our work presents novel insights for efficient analysis and detection of H2O content in methanol and could be used for H2O detection in other organic solvents.

9.
Methods Appl Fluoresc ; 12(3)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38537299

RESUMEN

Lead halide perovskite nanocrystals (PNCs) have attracted intense attention due to their excellent optoelectronic properties. In this work, a series of water-stable CsPb(Br/I)3PNCs fluorescent probes were prepared using an anion exchange method. It was found that the PNCs probes could be used to detect ascorbic acid (AA) in water, and interestingly, the FL spectra of the PNCs probes can be adjusted by controlling the concentration of KI in anion exchange to improve the detection selectivity of AA. The high sensitivity and selectivity make CsPb(Br/I)3PNCs an ideal material for AA sensing. The concentration of AA can be linearly measured in the range from 0.01 to 50µM, with a detection limit of 4.2 nM. The reason for the enhanced FL of CsPb(Br/I)3PNCs was studied, and it is considered that AA causes the aggregation of CsPb(Br/I)3PNCs. This strategy of improving the selectivity of the probe to the substrate by adjusting the spectrum will significantly expand the application of PNCs in the field of analysis and detection.

10.
Anal Chem ; 96(10): 4282-4289, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38469640

RESUMEN

Chirality is a widespread phenomenon in nature and in living organisms and plays an important role in living systems. The sensitive discrimination of chiral molecular enantiomers remains a challenge in the fields of chemistry and biology. Establishing a simple, fast, and efficient strategy to discriminate the spatial configuration of chiral molecular enantiomers is of great significance. Chiral perovskite nanocrystals (PNCs) have attracted much attention because of their excellent optical activity. However, it is a challenge to prepare perovskites with both chiral and fluorescence properties for chiral sensing. In this work, we synthesized two chiral fluorescent perovskite nanocrystal assembly (PNA) enantiomers by using l- or d-phenylalanine (Phe) as chiral ligands. PNA exhibited good fluorescence recognition for l- and d-proline (Pro). Homochiral interaction led to fluorescence enhancement, while heterochiral interaction led to fluorescence quenching, and there is a good linear relationship between the fluorescence changing rate and l- or d-Pro concentration. Mechanism studies show that homochiral interaction-induced fluorescence enhancement is attributed to the disassembly of chiral PNA, while no disassembly of chiral PNA was found in heterochiral interaction-induced fluorescence quenching, which is attributed to the substitution of Phe on the surface of chiral PNA by heterochiral Pro. This work suggests that chiral perovskite can be used for chiral fluorescence sensing; it will inspire the development of chiral nanomaterials and chiral optical sensors.

11.
Abdom Radiol (NY) ; 49(5): 1534-1544, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38546826

RESUMEN

PURPOSE: To investigate the correlation between quantitative MR parameters and prognostic factors in prostate cancer (PCa). METHOD: A total of 186 patients with pathologically confirmed PCa who underwent preoperative multiparametric MRI (mpMRI), including synthetic MRI (SyMRI), were enrolled from two medical centers. The histogram metrics of SyMRI [T1, T2, proton density (PD)] and apparent diffusion coefficient (ADC) values were extracted. The Mann‒Whitney U test or Student's t test was employed to determine the association between these histogram features and the prognostically relevant factors. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the differentiation performance. Spearman's rank correlation coefficients were calculated to determine the correlations between histogram parameters and the International Society of Urological Pathology (ISUP) grade group as well as pathological T stage. RESULTS: Significant correlations were found between the histogram parameters and the ISUP grade as well as pathological T stage of PCa. Among these histogram parameters, ADC_minimum had the strongest correlation with the ISUP grade (r = - 0.481, p < 0.001), and ADC_Median showed the strongest association with pathological T stage (r = - 0.285, p = 0.008). The ADC_10th percentile exhibited the highest performance in identifying clinically significant prostate cancer (csPCa) (AUC 0.833; 95% CI 0.771-0.883). When discriminating between the status of different prognostically relevant factors, a significant difference was observed between extraprostatic extension-positive and -negative cancers with regard to histogram parameters of the ADC map (10th percentile, 90th percentile, mean, median, minimum) and T1 map (minimum) (p = 0.002-0.032). Moreover, histogram parameters of the ADC map (90th percentile, maximum, mean, median), T2 map (10th percentile, median), and PD map (10th percentile, median) were significantly lower in PCa with perineural invasion (p = 0.009-0.049). The T2 values were significantly lower in patients with seminal vesicle invasion (minimum, p = 0.036) and positive surgical margin (10th percentile, 90th percentile, mean, median, and minimum, p = 0.015-0.025). CONCLUSION: Quantitative histogram parameters derived from synthetic MRI and ADC maps may have great potential for predicting the prognostic features of PCa.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Pronóstico , Persona de Mediana Edad , Imágenes de Resonancia Magnética Multiparamétrica/métodos , Clasificación del Tumor , Estudios Retrospectivos , Estadificación de Neoplasias , Imagen por Resonancia Magnética/métodos , Interpretación de Imagen Asistida por Computador/métodos
12.
Front Microbiol ; 15: 1342584, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38362502

RESUMEN

Trichoderma harzianum exhibits a strong biological control effect on many important plant pathogens, such as Fusarium oxysporum, Botrytis cinerea, and Meloidogyne. However, its biocontrol effectiveness is weakened or reduced under salt stress. The aim of this study was to investigate the molecular response of T. harzianum to salt stress at the whole-genome level. Here, we present a 44.47 Mb near-complete genome assembly of the T. harzianum qt40003 strain for the first time, which was assembled de novo with 7.59 Gb Nanopore sequencing long reads (~170-fold) and 5.2 Gb Illumina short reads (~116-fold). The assembled qt40003 genome contains 12 contigs, with a contig N50 of 4.81 Mb, in which four of the 12 contigs were entirely reconstructed in a single chromosome from telomere to telomere. The qt40003 genome contains 4.27 Mb of repeat sequences and 12,238 protein-coding genes with a BUSCO completeness of 97.5%, indicating the high accuracy and completeness of our gene annotations. Genome-wide transcriptomic analysis was used to investigate gene expression changes related to salt stress in qt40003 at 0, 2% (T2), and 4% (T4) sodium chloride concentrations. A total of 2,937 and 3,527 differentially expressed genes (DEGs) were obtained under T2 and T4 conditions, respectively. GO enrichment analysis showed that the T2-treatment DEGs were highly enriched in detoxification (p < 0.001), while the T4 DEGs were mainly enriched in cell components, mostly in cellular detoxification, cell surface, and cell wall. KEGG metabolic pathway analysis showed that 91 and 173 DEGs were significantly enriched in the T2 and T4 treatments, respectively (p < 0.01), mainly in the glutathione metabolism pathway. We further experimentally analyzed the differentially expressed glutathione transferase genes in the glutathione metabolic pathway, most of which were downregulated (13/15). In addition, we screened 13 genes related to active oxygen clearance, including six upregulated and seven downregulated genes, alongside five fungal hydrophobic proteins, of which two genes were highly expressed. Our study provides high-quality genome information for the use of T. harzianum for biological control and offers significant insights into the molecular responses of T. harzianum under salt-stress conditions.

13.
Mikrochim Acta ; 191(3): 125, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38326626

RESUMEN

Lead-based perovskites are highly susceptible to environmental influences, and their application in analytical chemistry, especially in aqueous solution, has been reported rarely. All-inorganic lead-free metal halide perovskites have been considered as a substitute for lead-based perovskites. Herein, a Cs2RbTbCl6 perovskite microcrystal (PMCs), which emits strong yellow-green fluorescence with a maximum emission wavelength at 547 nm, was for the first time  synthesized and characterized. The Cs2RbTbCl6 PMCs could be well dispersed in N,N-dimethylacetamide (DMF), and its fluorescence could be significantly enhanced by the addition of norfloxacin (NOR) in the aqueous solution. We found that the Cs2RbTbCl6 PMCs can be used as fluorescent probes (excitation, 365 nm; emission, 547 nm) to selectively detect NOR in a concentration range from 10.0 to 200.0 µM with the limit of detection (LOD) being 0.04 µM. The Cs2RbTbCl6 PMCs could also be adsorbed on filter paper to fabricate as a fluorescent test paper for visual detection of NOR under 365-nm ultraviolet (UV) lamp irradiation. The proposed method has the potential to establish a new analytical method to visualize the detection of NOR in aqueous environments and also promotes the application of all-inorganic lead-free perovskites for analytical detection in aqueous environments.

14.
Neurochem Res ; 49(6): 1592-1602, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38305960

RESUMEN

In the present study, sulfated polysaccharides were obtained by digestion of Sargassum horneri and preparation with enzyme-assisted extraction using three food-grade enzymes, and their anti- Alzheimer's activities were investigated. The results demonstrated that the crude sulfated polysaccharides extracted using AMGSP, CSP and VSP dose-dependently (25-100 µg·mL- 1) raised the spontaneous alternating manner (%) in the Y maze experiment of mice and reduced the escape latency time in Morris maze test. AMGSP, CSP and VSP also exhibited good anti-AChE and moderate anti-BuChE activities. CSP displayed the best inhibitory efficacy against AChE. with IC50 values of 9.77 µM. And, CSP also exhibited good inhibitory selectivity of AChE over BuChE. Next, CSP of the best active crude extract was separated by the preparation type high performance liquid phase to obtain the sulphated fucooligosaccharide section: SFcup (→3-α-L-fucp(2-SO3-)-1→4-α-L-fucp(2,3-SO3-)-1→section), SFcup showed a best inhibitory efficacy against AChE with IC50 values of 4.03 µM. The kinetic research showed that SFcup inhibited AChE through dual binding sites. Moreover, the molecular docking of SFcup at the AChE active site was in accordance with the acquired pharmacological results.


Asunto(s)
Acetilcolinesterasa , Enfermedad de Alzheimer , Inhibidores de la Colinesterasa , Simulación del Acoplamiento Molecular , Oligosacáridos , Sargassum , Sargassum/química , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/uso terapéutico , Ratones , Acetilcolinesterasa/metabolismo , Oligosacáridos/farmacología , Oligosacáridos/química , Oligosacáridos/aislamiento & purificación , Masculino , Sulfatos/química , Sulfatos/farmacología , Butirilcolinesterasa/metabolismo , Aprendizaje por Laberinto/efectos de los fármacos , Polisacáridos/farmacología , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Relación Dosis-Respuesta a Droga
15.
Br J Radiol ; 97(1153): 201-209, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263836

RESUMEN

OBJECTIVES: To create a MRI-derived radiomics nomogram that combined clinicopathological factors and radiomics signature (Rad-score) for predicting disease-free survival (DFS) in patients with bladder cancer (BCa) following partial resection (PR) or radical cystectomy (RC), including lymphadenectomy (LAE). METHODS: Finally, 80 patients with BCa after PR or RC with LAE were enrolled. Patients were randomly split into training (n = 56) and internal validation (n = 24) cohorts. Radiomic features were extracted from T2-weighted, dynamic contrast-enhanced, diffusion-weighted imaging, and apparent diffusion coefficient sequence. The least absolute shrinkage and selection operator (LASSO) Cox regression algorithm was applied to choose the valuable features and construct the Rad-score. The DFS prediction model was built using the Cox proportional hazards model. The relationship between the Rad-score and DFS was assessed using Kaplan-Meier analysis. A radiomics nomogram that combined the Rad-score and clinicopathological factors was created for individualized DFS estimation. RESULTS: In both the training and validation cohorts, the Rad-score was positively correlated with DFS (P < .001). In the validation cohort, the radiomics nomogram combining the Rad-score, tumour pathologic stage (pT stage), and lymphovascular invasion (LVI) achieved better performance in DFS prediction (C-index, 0.807; 95% CI, 0.713-0.901) than either the clinicopathological (C-index, 0.654; 95% CI, 0.467-0.841) or Rad-score-only model (C-index, 0.770; 95% CI, 0.702-0.837). CONCLUSION: The Rad-score was an independent predictor of DFS for patients with BCa after PR or RC with LAE, and the radiomics nomogram that combined the Rad-score, pT stage, and LVI achieved better performance in individual DFS prediction. ADVANCES IN KNOWLEDGE: This study provided a non-invasive and simple method for personalized and accurate prediction of DFS in BCa patients after PR or RC.


Asunto(s)
Cistectomía , Neoplasias de la Vejiga Urinaria , Humanos , Supervivencia sin Enfermedad , Nomogramas , Radiómica
16.
IEEE Trans Med Imaging ; 43(5): 1766-1781, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38163304

RESUMEN

We proposed a technique of coincidence detection of cascade photons (CDCP) to enhance preclinical SPECT imaging of therapeutic radionuclides emitting cascade photons, such as Lu-177, Ac-225, Ra-223, and In-111. We have carried out experimental studies to evaluate the proposed CDCP-SPECT imaging of low-activity radionuclides using a prototype coincidence detection system constructed with large-volume cadmium zinc telluride (CZT) imaging spectrometers and a pinhole collimator. With In-111 in experimental studies, the CDCP technique allows us to improve the signal-to-contamination in the projection (Projection-SCR) by ~53 times and reduce ~98% of the normalized contamination. Compared to traditional scatter correction, which achieves a Projection-SCR of 1.00, our CDCP method boosts it to 15.91, showing enhanced efficacy in reducing down-scattered contamination, especially at lower activities. The reconstructed images of a line source demonstrated the dramatic enhancement of the image quality with CDCP-SPECT compared to conventional and triple-energy-window-corrected SPECT data acquisition. We also introduced artificial energy blurring and Monte Carlo simulation to quantify the impact of detector performance, especially its energy resolution and timing resolution, on the enhancement through the CDCP technique. We have further demonstrated the benefits of the CDCP technique with simulation studies, which shows the potential of improving the signal-to-contamination ratio by 300 times with Ac-225, which emits cascade photons with a decay constant of ~0.1 ns. These results have demonstrated the potential of CDCP-enhanced SPECT for imaging a super-low level of therapeutic radionuclides in small animals.


Asunto(s)
Cadmio , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Fotones , Telurio , Tomografía Computarizada de Emisión de Fotón Único , Zinc , Tomografía Computarizada de Emisión de Fotón Único/métodos , Animales , Procesamiento de Imagen Asistido por Computador/métodos , Radioisótopos/química , Ratones , Método de Montecarlo
17.
Luminescence ; 39(1): e4615, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37957886

RESUMEN

By using the method of low-temperature crystallization, CsPbBr3 perovskite nanocrystals (PNCs) coated with trifluoroacetyl lysine (Tfa-Lys) and oleamine (Olam) were synthesized in aqueous solution. The structure of the CsPbBr3 PNCs was characterized by many methods, such as ultraviolet (UV)-visible absorption spectrophotometer, fluorescence spectrophotometer, transmission electron microscopy (TEM), and X-ray diffraction (XRD) pattern. The fluorescence emission of the CsPbBr3 PNCs is stable in water for about 1 day at room temperature. It was also found that the fluorescence of the PNCs could be obviously and selectively quenched after the addition of mercury ion (Hg2+ ), allowing a visual detection of Hg2+ by the naked eye under UV light illumination. The fluorescence quenching rate (I0 /I) has a good linear relationship with the addition of Hg2+ in the concentration range 0.075 to 1.5 mg/L, with a correlation coefficient (R2 ) of 0.997, and limit of detection of 0.046 mg/L. The fluorescence quenching mechanism of the PNCs was determined by the fluorescence lifetime and X-ray photoelectron spectroscopy (XPS) of the PNCs. Overall, the synthesis method for CsPbBr3 PNCs is simple and rapid, and the as-prepared PNCs are stable in water that could be conveniently used for selective detection of Hg2+ in the water environment.


Asunto(s)
Compuestos de Calcio , Mercurio , Nanopartículas , Titanio , Agua/química , Óxidos/química , Nanopartículas/química
18.
Plant Commun ; 5(2): 100723, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-37742073

RESUMEN

Root-knot nematodes (RKNs) cause huge agricultural losses every year. They secrete a repertoire of effectors to facilitate parasitism through the induction of plant-derived giant feeding cells, which serve as their sole source of nutrients. However, the mode of action of these effectors and their targeted host proteins remain largely unknown. In this study, we investigated the role of the effector Mi2G02 in Meloidogyne incognita parasitism. Host-derived Mi2G02 RNA interference in Arabidopsis thaliana affected giant cell development, whereas ectopic expression of Mi2G02 promoted root growth and increased plant susceptibility to M. incognita. We used various combinations of approaches to study the specific interactions between Mi2G02 and A. thaliana GT-3a, a trihelix transcription factor. GT-3a knockout in A. thaliana affected feeding-site development, resulting in production of fewer egg masses, whereas GT-3a overexpression in A. thaliana increased susceptibility to M. incognita and also root growth. Moreover, we demonstrated that Mi2G02 plays a role in maintaining GT-3a protein stabilization by inhibiting the 26S proteasome-dependent pathway, leading to suppression of TOZ and RAD23C expression and thus promoting nematode parasitism. This work enhances our understanding of how a pathogen effector manipulates the role and regulation of a transcription factor by interfering with a proteolysis pathway to reprogram gene expression for development of nematode feeding cells.


Asunto(s)
Arabidopsis , Nematodos , Animales , Factores de Transcripción/genética , Arabidopsis/genética , Plantas Modificadas Genéticamente , Interferencia de ARN , Nematodos/genética
19.
IEEE Trans Radiat Plasma Med Sci ; 7(1): 18-32, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38106623

RESUMEN

We constructed a prototype positron emission tomography (PET) system and experimentally evaluated large-volume 3-D cadmium zinc telluride (CZT) detectors for potential use in Compton-enhanced PET imaging. The CZT spectrometer offers sub-0.5-mm spatial resolution, an ultrahigh energy resolution (~1% @ 511 keV), and the capability of detecting multiple gamma-ray interactions that simultaneously occurred. The system consists of four CZT detector panels with a detection area of around 4.4 cm × 4.4 cm. The distance between the front surfaces of the two opposite CZT detector panels is ~80 mm. This system allows us to detect coincident annihilation photons and Compton interactions inside the detectors and then, exploit Compton kinematics to predict the first Compton interaction site and reject chance coincidences. We have developed a numerical integration technique to model the near-field Compton response that incorporates Doppler broadening, detector's finite resolutions, and the distance between the first and second interactions. This method was used to effectively reject random and scattered coincidence events. In the preliminary imaging studies, we have used point sources, line sources, a custom-designed resolution phantom, and a commercial image quality (IQ) phantom to demonstrate an imaging resolution of approximately 0.75 mm in PET images, and Compton-based enhancement.

20.
Knee Surg Sports Traumatol Arthrosc ; 31(12): 5987-5993, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37943329

RESUMEN

PURPOSE: To investigate the time-dependent nature of clinically significant outcomes, including the minimal clinically important difference (MCID), substantial clinical benefit, and Patient Acceptable Symptomatic State (PASS) after arthroscopic superior capsular reconstruction, and the factors contributing to the achievement of early clinically significant outcomes. METHODS: Patients who underwent ASCR between March 2015 and September 2020 with complete preoperative and postoperative 6-month, 1-year, and 2-year patient-reported outcome measures (PROMs) were retrospectively analysed. Threshold values for MCID, substantial clinical benefit, and PASS were obtained from the previous literature for the PROMs. The time required to achieve clinically significant outcomes was calculated using Kaplan-Meier analysis. Multivariate Cox regression was performed to evaluate the variables predictive of an earlier or delayed achievement of MCID. RESULTS: Fifty-nine patients with a mean age of 64.5 ± 8.7 years old were included. The time of mean achievement of MCID, substantial clinical benefit, and PASS for VAS was 11.2 ± 0.9, 16.3 ± 1.1, and 16.6 ± 0.9 months, respectively. The time of mean achievement of MCID, substantial clinical benefit, and PASS for ASES was 13.2 ± 1.0, 16.8 ± 1.0, and 18.3 ± 0.9 months, respectively. The time of mean achievement of MCID, substantial clinical benefit, and PASS for the Constant score was 11.6 ± 0.9, 15.1 ± 1.0, and 14.7 ± 0.9 months, respectively. The time of mean achievement of MCID, substantial clinical benefit, and PASS for SANE was 14.4 ± 1.0, 16.1 ± 1.0, and 15.5 ± 0.8 months, respectively. Patients with a higher preoperative VAS score achieved an earlier MCID for VAS (P = 0.014). However, patients with a higher preoperative ASES and SANE scores achieved delayed MCID for ASES and SANE (P = 0.026, and P < 0.001, respectively). CONCLUSION: Most patients achieved MCIDs around 1 year after arthroscopic superior capsular reconstruction. A higher preoperative VAS score favours faster MCID achievement, while higher preoperative ASES and SANE scores contribute to delayed MCID achievement. STUDY DESIGN: Cohort study LEVEL OF EVIDENCE: Level IV.


Asunto(s)
Artroscopía , Diferencia Mínima Clínicamente Importante , Humanos , Persona de Mediana Edad , Anciano , Estudios de Cohortes , Resultado del Tratamiento , Estudios Retrospectivos , Medición de Resultados Informados por el Paciente
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