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1.
J Agric Food Chem ; 72(14): 7765-7773, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38556742

RESUMO

Climate change affects the content and composition of soil organic carbon (SOC). However, warming-induced changes in the SOC compounds remain unknown. Using nuclear magnetic resonance spectroscopy, molecular mixing models, and Fourier transform ion cyclotron resonance mass spectrometry, we analyzed the variations and relationships in molecular compounds in Mollisol with 10-56 g C kg-1 soil-1 by translocating soils under six climate regimes. We found that increased temperature and precipitation were negatively correlated with carbohydrate versus lipid and lignin versus protein. The former was consistent across soils with varying SOC contents, but the latter decreased as the SOC content increased. The carbohydrate-lipid correlations were related to dithionite-citrate-extractable Fe, while the lignin-protein correlations were linked to changes in moisture and pyrophosphate-extractable Fe/Al. Our findings indicate that the reduction in the mineral protection of SOC is associated with molecular alterations in SOC under warming conditions.


Assuntos
Carbono , Solo , Solo/química , Carbono/metabolismo , Lignina , Lipídeos , Carboidratos
2.
ACS Appl Mater Interfaces ; 16(11): 13914-13926, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38447591

RESUMO

Polarization-sensitive photodetectors have attracted considerable attention owing to their potential application prospects in navigation, optical switching, and communication. However, it remains challenging to develop a facile and effective strategy to simultaneously meet the demands of low power consumption, high performance, and excellent polarization sensitivity. Herein, a series of low-symmetry two-dimensional (2D) ReSe2 Schottky photodetectors with geometry-asymmetric contacts are constructed. These devices exhibit excellent photoelectrical performance and impressive polarization sensitivity in the self-powered mode owing to the difference in the Schottky barrier height induced by the asymmetric contact areas, interfacial states, and thickness difference. Particularly, an outstanding responsivity of 379 mA/W, a decent specific detectivity of 6.8 × 1011 Jones, and a high light on/off ratio (Ilight/Idark) of over 105 under 635 nm light illumination are achieved. Scanning photocurrent mapping (SPCM) measurements further confirm that the ReSe2/drain overlapped region (corresponding to the smaller contact area side) with a higher Schottky barrier height plays a dominant role in the generation of photocurrent. Furthermore, the proposed device displays impressive polarization ratios (PRs) of 3.1 and 3.6 at zero bias under 635 and 808 nm irradiation, respectively. The high-resolution single-pixel imaging capability is also demonstrated. This work reveals the great potential of the ReSe2 Schottky photodetector with geometry-asymmetric contacts for high-performance, self-powered, and polarization-sensitive photodetection.

3.
J Magn Reson ; 359: 107615, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38310668

RESUMO

Accumulating several scans of free induction decays is always needed to improve the signal-to-noise ratio of NMR spectra, especially for the low gyromagnetic ratio solid-state NMR. In this study, we present a new denoising approach based on the correlations between multiple similar NMR spectra. Contrary to the simple averaging of multiple scans or denoising the final averaged spectrum, we propose a Wavelet-based Denoising technique for Multiple Similar scans(WDMS). Firstly, the stationary wavelet transform is applied to decompose every spectrum into approximation coefficients and detail coefficients. Then, the detail coefficients are multiplied by weights calculated based on Pearson's correlation coefficient and structural similarity index between approximation coefficients of different spectra. Finally, the average of these detailed components is used to denoise the spectra. The proposed method is carried on the assumption that noise between multiple spectra is uncorrelated while peak signal information is similar between different spectra, thus preserving the possibility of applying further processing to the data. As a demonstration, the standard wavelet denoise is applied to the WDMS-processed spectra, achieving a further increase in the S/N ratio. We confirm the reliability of the denoising approach based on multiple scans on 1D/2D solid-state MAS/static NMR spectra. In addition, we also show that this method can be used to deal with a single Car-Purcell-Meiboom-Gill (CPMG) echo train.

4.
Magn Reson Med ; 91(4): 1368-1383, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38073072

RESUMO

PURPOSE: To design an unsupervised deep learning (DL) model for correcting Nyquist ghosts of single-shot spatiotemporal encoding (SPEN) and evaluate the model for real MRI applications. METHODS: The proposed method consists of three main components: (1) an unsupervised network that combines Residual Encoder and Restricted Subspace Mapping (RERSM-net) and is trained to generate a phase-difference map based on the even and odd SPEN images; (2) a spin physical forward model to obtain the corrected image with the learned phase difference map; and (3) cycle-consistency loss that is explored for training the RERSM-net. RESULTS: The proposed RERSM-net could effectively generate smooth phase difference maps and correct Nyquist ghosts of single-shot SPEN. Both simulation and real in vivo MRI experiments demonstrated that our method outperforms the state-of-the-art SPEN Nyquist ghost correction method. Furthermore, the ablation experiments of generating phase-difference maps show the advantages of the proposed unsupervised model. CONCLUSION: The proposed method can effectively correct Nyquist ghosts for the single-shot SPEN sequence.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Imagem Ecoplanar/métodos , Encéfalo/diagnóstico por imagem , Algoritmos , Imagens de Fantasmas , Artefatos
5.
J Investig Med ; 72(1): 3-12, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37726952

RESUMO

The monocyte to high-density lipoprotein-cholesterol (HDL-C) ratio (monocyte-to-HDL-C ratio) was proposed as a marker of atherosclerosis. Osteoporosis and atherosclerosis share common risk factors and pathophysiological mechanisms. This study aimed to assess the relationship between monocyte-to-HDL-C ratio and osteoporosis. Participants aged ≥50 years with complete bone mineral density (BMD), monocyte, and HDL-C examination data from the National Health and Nutrition Examination Survey (NHANES) 2013-2014 were included. Descriptive analysis was performed separately according to males and females. Weight linear regression and weight logistic regression analyses were used to analyze the association between the monocyte-to-HDL-C ratio and BMD and osteopenia and osteoporosis and vertebral fracture. A total of 1804 participants were included. Among the participants with osteopenia, 398 (48.31%) were males and 466 (51.91%) were females. Among those with osteoporosis, 38 (2.77%) were males and 95 (9.50%) were females. In females, monocyte-to-HDL-C ratio was negatively associated with femoral neck BMD (regression coefficient (ß) = -0.18; 95% confidence interval (CI): (-0.29, -0.07)) and high monocyte-to-HDL-C ratio was associated with higher odds of osteopenia (odds ratio (OR) = 1.22; 95% CI: (1.01, 1.47)) and osteoporosis (OR = 1.68; 95% CI: (1.13, 2.49)) after adjusting for confounders. In males, only monocyte-to-HDL-C ratio >0.35 was observed to be associated with higher odds of osteoporosis (OR = 1.96; 95% CI: (1.02, 3.79)). Stratified analyses showed that similar results were also found in different populations. This study showed that the monocyte-to-HDL-C ratio was negatively associated with BMD and the risk of osteopenia and osteoporosis in females. The monocyte-to-HDL-C ratio may be a new marker of osteoporosis or osteopenia.


Assuntos
Aterosclerose , Doenças Ósseas Metabólicas , Osteoporose , Masculino , Feminino , Humanos , Inquéritos Nutricionais , HDL-Colesterol , Monócitos , Osteoporose/complicações , Densidade Óssea , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/diagnóstico , Aterosclerose/complicações
6.
Int J Mol Sci ; 24(23)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38069384

RESUMO

The gibberellic acid-stimulated Arabidopsis (GASA) gene family plays a crucial role in growth, development, and stress response, and it is specific to plants. This gene family has been extensively studied in various plant species, and its functional role in pineapple has yet to be characterized. In this study, 15 AcGASA genes were identified in pineapple through a genome-wide scan and categorized into three major branches based on a phylogenetic tree. All AcGASA proteins share a common structural domain with 12 cysteine residues, but they exhibit slight variations in their physicochemical properties and motif composition. Predictions regarding subcellular localization suggest that AcGASA proteins are present in the cell membrane, Golgi apparatus, nucleus, and cell wall. An analysis of gene synteny indicated that both tandem and segmental repeats have a significant impact on the expansion of the AcGASA gene family. Our findings demonstrate the differing regulatory effects of these hormones (GA, NAA, IAA, MeJA, and ABA) on the AcGASA genes. We analyzed the expression profiles of GASA genes in different pineapple tissue parts, and the results indicated that AcGASA genes exhibit diverse expression patterns during the development of different plant tissues, particularly in the regulation of floral organ development. This study provides a comprehensive understanding of GASA family genes in pineapple. It serves as a valuable reference for future studies on the functional characterization of GASA genes in other perennial herbaceous plants.


Assuntos
Ananas , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Ananas/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
7.
J Magn Reson ; 357: 107582, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37950959

RESUMO

The aim of this work is to develop a Halbach magnet that possesses characteristics such as easy-built, low cost and high homogeneity for use in a portable low-field NMR (LF-NMR) system. Considering portability, a 4-ring Halbach magnet was designed through simulation and mechanical modelling, which was successfully constructed in a general laboratory setting. The obtained field strength (B0) was 0.169 T, with an initial homogeneity of 8204 ppm within a sphere with a diameter of 20 mm. To enhance robustness, efficiency and effectiveness of shimming, an optimized target-field passive shimming method was proposed. Subsequently, the homemade spectrometer was used to run NMR experiments on the Halbach magnet. The 1H NMR linewidths of water samples became significantly narrower after passive shimming, e.g., the linewidth of a sample with a diameter of 3 mm and a length of 3 mm reduced from 452.3 Hz (62.5 ppm) to 12.9 Hz (1.8 ppm), which was much less than 102 Hz. The NMR results demonstrate that the proposed passive shimming method can achieve high homogeneity, and the developed Halbach magnet is capable of satisfying numerous LF-NMR applications.

8.
Sci Adv ; 9(44): eadj1092, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37910610

RESUMO

Parkinson's disease (PD) is characterized by the pathologic aggregation and prion-like propagation of α-synuclein (α-syn). Emerging evidence shows that fungal infections increase the incidence of PD. However, the molecular mechanisms by which fungi promote the onset of PD are poorly understood. Here, we show that nasal infection with Saccharomyces cerevisiae (S. cerevisiae) in α-syn A53T transgenic mice accelerates the aggregation of α-syn. Furthermore, we found that Sup35, a prion protein from S. cerevisiae, is the key factor initiating α-syn pathology induced by S. cerevisiae. Sup35 interacts with α-syn and accelerates its aggregation in vitro. Notably, injection of Sup35 fibrils into the striatum of wild-type mice led to α-syn pathology and PD-like motor impairment. The Sup35-seeded α-syn fibrils showed enhanced seeding activity and neurotoxicity compared with pure α-syn fibrils in vitro and in vivo. Together, these observations indicate that the yeast prion protein Sup35 initiates α-syn pathology in PD.


Assuntos
Doença de Parkinson , Saccharomyces cerevisiae , alfa-Sinucleína , Animais , Camundongos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Camundongos Transgênicos , Doença de Parkinson/metabolismo , Proteínas Priônicas/metabolismo , Príons/metabolismo , Saccharomyces cerevisiae/metabolismo
9.
Nat Food ; 4(10): 912-924, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37783790

RESUMO

Aluminium (Al) toxicity impedes crop growth in acidic soils and is considered the second largest abiotic stress after drought for crops worldwide. Despite remarkable progress in understanding Al resistance in plants, it is still unknown whether and how the soil microbiota confers Al resistance to crops. Here we found that a synthetic community composed of highly Al-resistant bacterial strains isolated from the rice rhizosphere increased rice yield by 26.36% in acidic fields. The synthetic community harvested rhizodeposited carbon for successful proliferation and mitigated soil acidification and Al toxicity through extracellular protonation. The functional coordination between plants and microbes offers a promising way to increase the usage of legacy phosphorus in topsoil. These findings highlight the potential of microbial tools for advancing sustainable agriculture in acidic soils.


Assuntos
Microbiota , Oryza , Solo , Fósforo , Alumínio/toxicidade , Produtos Agrícolas , Ácidos
10.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37833903

RESUMO

Albino seedlings that arise during seed reproduction can have a significant impact on plant growth and breeding. In this research, we present the first report of albino occurrences in the seed reproduction process of Prunus salicina and describe the cytological, physiological, and transcriptomic changes observed in albino seedlings. The albino seedlings which were observed in several plum cultivars exhibited abnormal chloroplast ultrastructure and perturbed stomatal structure. Compared to normal seedlings, the photosynthetic pigment contents in albino seedlings decreased by more than 90%, accompanied by significant reductions in several chlorophyll fluorescence parameters. Furthermore, substantially changed photosynthetic parameters indicated that the photosynthetic capacity and stomatal function were impaired in albino seedlings. Additionally, the activities of the antioxidant enzyme were drastically altered against the background of higher proline and lower ascorbic acid in leaves of albino seedlings. A total of 4048 differentially expressed genes (DEGs) were identified through transcriptomic sequencing, and the downregulated DEGs in albino seedlings were greatly enriched in the pathways for photosynthetic antenna proteins and flavonoid biosynthesis. GLK1 and Ftsz were identified as candidate genes responsible for the impaired chloroplast development and division in albino seedlings. Additionally, the substantial decline in the expression levels of examined photosystem-related chloroplast genes was validated in albino seedlings. Our findings shed light on the intricate physiological and molecular mechanisms driving albino plum seedling manifestation, which will contribute to improving the reproductive and breeding efforts of plums.


Assuntos
Prunus domestica , Perfilação da Expressão Gênica , Fotossíntese/genética , Melhoramento Vegetal , Folhas de Planta/genética , Prunus domestica/genética , Plântula/metabolismo , Transcriptoma , China
11.
Cell Rep ; 42(11): 113342, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897723

RESUMO

The molecular mechanisms that trigger Tau aggregation in Alzheimer's disease (AD) remain elusive. Fungi, especially Saccharomyces cerevisiae (S. cerevisiae), can be found in brain samples from patients with AD. Here, we show that the yeast protein Ure2p from S. cerevisiae interacts with Tau and facilitates its aggregation. The Ure2p-seeded Tau fibrils are more potent in seeding Tau and causing neurotoxicity in vitro. When injected into the hippocampus of Tau P301S transgenic mice, the Ure2p-seeded Tau fibrils show enhanced seeding activity compared with pure Tau fibrils. Strikingly, intracranial injection of Ure2p fibrils promotes the aggregation of Tau and cognitive impairment in Tau P301S mice. Furthermore, intranasal infection of S. cerevisiae in the nasal cavity of Tau P301S mice accelerates the aggregation of Tau. Together, these observations indicate that the yeast protein Ure2p initiates Tau pathology. Our results provide a conceptual advance that non-mammalian prions may cross-seed mammalian prion-like proteins.


Assuntos
Glutationa Peroxidase , Príons , Proteínas de Saccharomyces cerevisiae , Tauopatias , Proteínas tau , Animais , Camundongos , Modelos Animais de Doenças , Camundongos Transgênicos , Príons/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas tau/metabolismo , Tauopatias/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Glutationa Peroxidase/metabolismo
12.
Bioengineering (Basel) ; 10(10)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37892922

RESUMO

This study aims to propose and evaluate DR-CycleGAN, a disentangled unsupervised network by introducing a novel content-consistency loss, for removing arterial-phase motion artifacts in gadoxetic acid-enhanced liver MRI examinations. From June 2020 to July 2021, gadoxetic acid-enhanced liver MRI data were retrospectively collected in this center to establish training and testing datasets. Motion artifacts were semi-quantitatively assessed using a five-point Likert scale (1 = no artifact, 2 = mild, 3 = moderate, 4 = severe, and 5 = non-diagnostic) and quantitatively evaluated using the structural similarity index (SSIM) and peak signal-to-noise ratio (PSNR). The datasets comprised a training dataset (308 examinations, including 58 examinations with artifact grade = 1 and 250 examinations with artifact grade ≥ 2), a paired test dataset (320 examinations, including 160 examinations with artifact grade = 1 and paired 160 examinations with simulated motion artifacts of grade ≥ 2), and an unpaired test dataset (474 examinations with artifact grade ranging from 1 to 5). The performance of DR-CycleGAN was evaluated and compared with a state-of-the-art network, Cycle-MedGAN V2.0. As a result, in the paired test dataset, DR-CycleGAN demonstrated significantly higher SSIM and PSNR values and lower motion artifact grades compared to Cycle-MedGAN V2.0 (0.89 ± 0.07 vs. 0.84 ± 0.09, 32.88 ± 2.11 vs. 30.81 ± 2.64, and 2.7 ± 0.7 vs. 3.0 ± 0.9, respectively; p < 0.001 each). In the unpaired test dataset, DR-CycleGAN also exhibited a superior motion artifact correction performance, resulting in a significant decrease in motion artifact grades from 2.9 ± 1.3 to 2.0 ± 0.6 compared to Cycle-MedGAN V2.0 (to 2.4 ± 0.9, p < 0.001). In conclusion, DR-CycleGAN effectively reduces motion artifacts in the arterial phase images of gadoxetic acid-enhanced liver MRI examinations, offering the potential to enhance image quality.

13.
Org Biomol Chem ; 21(23): 4881-4892, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37259536

RESUMO

An aminomethylation reaction of fulleropyrrolidines bearing ketone moieties in the presence of N-unsubstituted fulleropyrrolidines and paraformaldehyde with the aid of p-toluenesulfonic acid afforded a series of scarce pendant fullerene dimers. A simple change of reaction substrates from ketone to ketone-containing fulleropyrrolidines successfully realized the synthesis of a variety of novel pendant fullerene dimers, including those from methyl ketone-containing fulleropyrrolidines, which were considered to produce the known bridged fullerene dimers. It should be noted that pendant fullerene dimers are usually difficult to prepare by other methods and may have promising applications in perovskite solar cells. Density functional theory (DFT) has been employed to elucidate the regioselectivity of methyl ketone-containing fulleropyrrolidines to yield exclusively pendant fullerene dimers by investigating the Gibbs free energy profile of the reaction starting from methyl ketone-containing fulleropyrrolidines and iminium intermediates.

14.
Prog Neurobiol ; 226: 102462, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150314

RESUMO

Pathologic aggregation and prion-like propagation of α-synuclein (α-syn) are the hallmarks of Parkinson's disease (PD). Emerging evidence shows that type 2 diabetes mellitus (T2DM) is a risk factor for PD. Interestingly, T2DM is characterized by the amyloid deposition of islet amyloid polypeptide (IAPP) in the pancreas. Although T2DM and PD share pathological similarities, the underlying molecular mechanisms bridging these two diseases remain unknown. Here, we report that IAPP co-deposits with α-syn in the brains of PD patients. IAPP interacts with α-syn and accelerates its aggregation. In addition, the IAPP-seeded α-syn fibrils show enhanced seeding activity and neurotoxicity compared with pure α-syn fibrils in vitro and in vivo. Strikingly, intravenous injection of IAPP fibrils into α-syn A53T transgenic mice or human SNCA transgenic mice accelerated the aggregation of α-syn and PD-like motor deficits. Taken together, these findings support that IAPP acts as a trigger of α-syn pathology in PD, and provide a mechanistic explanation for the increased risk and faster progression of PD in patients with T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Doença de Parkinson , Camundongos , Animais , Humanos , Doença de Parkinson/patologia , alfa-Sinucleína , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Camundongos Transgênicos , Amiloide/química
15.
Hamostaseologie ; 43(4): 281-288, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37137330

RESUMO

The performances of RIETE, VTE-BLEED, SWITCO65 + , and Hokusai-VTE scores for predicting major bleeding events in hospitalized elderly cancer patients with venous thromboembolism (VTE) have not been evaluated. This study validated the performances of these scoring systems in a cohort of elderly cancer patients with VTE. Between June 2015 and March 2021, a total of 408 cancer patients (aged ≥ 65 years) with acute VTE were consecutively enrolled. The overall rates of in-hospital major bleeding and clinically relevant bleeding (CRB) were 8.3% (34/408) and 11.8% (48/408), respectively. RIETE score could categorize patients with increasing rate of major bleeding and CRB into low-/intermediate- and high-risk categories (7.1 vs. 14.1%, p = 0.05 and 10.1 vs. 19.7%, p = 0.02, respectively). The discriminative power of the four scores for predicting major bleeding was poor to moderate, indicated by areas under the receiver operating characteristic curves (0.45 [95% confidence interval, CI: 0.35-0.55] for Hokusai-VTE, 0.54 [95% CI: 0.43-0.64] for SWITCO65 + , 0.58 [95% CI: 0.49-0.68] for VTE-BLEED, and 0.61 [95% CI: 0.51-0.71] for RIETE). RIETE score might be used to predict major bleeding in hospitalized elderly cancer patients with acute VTE.


Assuntos
Neoplasias , Tromboembolia Venosa , Idoso , Humanos , Tromboembolia Venosa/complicações , Tromboembolia Venosa/diagnóstico , Hemorragia/diagnóstico , Hemorragia/etiologia , Neoplasias/complicações , Valor Preditivo dos Testes , Anticoagulantes , Fatores de Risco
16.
Front Plant Sci ; 14: 1159223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123828

RESUMO

Background: Pineapple is the only commercially grown fruit crop in the Bromeliaceae family and has significant agricultural, industrial, economic, and ornamental value. GRF (growth-regulating factor) proteins are important transcription factors that have evolved in seed plants (embryophytes). They contain two conserved domains, QLQ (Gln, Leu, Gln) and WRC (Trp, Arg, Cys), and regulate multiple aspects of plant growth and stress response, including floral organ development, leaf growth, and hormone responses. The GRF family has been characterized in a number of plant species, but little is known about this family in pineapple and other bromeliads. Main discoveries: We identified eight GRF transcription factor genes in pineapple, and phylogenetic analysis placed them into five subfamilies (I, III, IV, V, VI). Segmental duplication appeared to be the major contributor to expansion of the AcGRF family, and the family has undergone strong purifying selection during evolution. Relative to that of other gene families, the gene structure of the GRF family showed less conservation. Analysis of promoter cis-elements suggested that AcGRF genes are widely involved in plant growth and development. Transcriptome data and qRT-PCR results showed that, with the exception of AcGRF5, the AcGRFs were preferentially expressed in the early stage of floral organ development and AcGRF2 was strongly expressed in ovules. Gibberellin treatment significantly induced AcGRF7/8 expression, suggesting that these two genes may be involved in the molecular regulatory pathway by which gibberellin promotes pineapple fruit expansion. Conclusion: AcGRF proteins appear to play a role in the regulation of floral organ development and the response to gibberellin. The information reported here provides a foundation for further study of the functions of AcGRF genes and the traits they regulate.

17.
Magn Reson Med ; 90(2): 458-472, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37052369

RESUMO

PURPOSE: To design an unsupervised deep neural model for correcting susceptibility artifacts in single-shot Echo Planar Imaging (EPI) and evaluate the model for preclinical and clinical applications. METHODS: This work proposes an unsupervised cycle-consistent model based on the restricted subspace field map to take advantage of both the deep learning (DL) and the reverse polarity-gradient (RPG) method for single-shot EPI. The proposed model consists of three main components: (1) DLRPG neural network (DLRPG-net) to obtain field maps based on a pair of images acquired with reversed phase encoding; (2) spin physical model-based modules to obtain the corrected undistorted images based on the learned field map; and (3) cycle-consistency loss between the input images and back-calculated images from each cycle is explored for network training. In addition, the field maps generated by DLRPG-net belong to a restricted subspace, which is a span of predefined cubic splines to ensure the smoothness of the field maps and avoid blurring in the corrected images. This new method is trained and validated on both preclinical and clinical datasets for diffusion MRI. RESULTS: The proposed network could effectively generate smooth field maps and correct susceptibility artifacts in single-shot EPI. Simulated and in vivo preclinical/clinical experiments demonstrated that our method outperforms the state-of-the-art susceptibility artifact correction methods. Furthermore, the ablation experiments of the cycle-consistent network and the restricted subspace in generating field maps did show the advantages of DLRPG-net. CONCLUSION: The proposed method (DLRPG-net) can effectively correct susceptibility artifacts for preclinical and clinical single-shot EPI sequences.


Assuntos
Artefatos , Imagem Ecoplanar , Imagem Ecoplanar/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
18.
Comput Struct Biotechnol J ; 21: 1606-1620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874158

RESUMO

Short-chain fatty acids (SCFAs) exhibit anticancer activity in cellular and animal models of colon cancer. Acetate, propionate, and butyrate are the three major SCFAs produced from dietary fiber by gut microbiota fermentation and have beneficial effects on human health. Most previous studies on the antitumor mechanisms of SCFAs have focused on specific metabolites or genes involved in antitumor pathways, such as reactive oxygen species (ROS) biosynthesis. In this study, we performed a systematic and unbiased analysis of the effects of acetate, propionate, and butyrate on ROS levels and metabolic and transcriptomic signatures at physiological concentrations in human colorectal adenocarcinoma cells. We observed significantly elevated levels of ROS in the treated cells. Furthermore, significantly regulated signatures were involved in overlapping pathways at metabolic and transcriptomic levels, including ROS response and metabolism, fatty acid transport and metabolism, glucose response and metabolism, mitochondrial transport and respiratory chain complex, one-carbon metabolism, amino acid transport and metabolism, and glutaminolysis, which are directly or indirectly linked to ROS production. Additionally, metabolic and transcriptomic regulation occurred in a SCFAs types-dependent manner, with an increasing degree from acetate to propionate and then to butyrate. This study provides a comprehensive analysis of how SCFAs induce ROS production and modulate metabolic and transcriptomic levels in colon cancer cells, which is vital for understanding the mechanisms of the effects of SCFAs on antitumor activity in colon cancer.

19.
Med Phys ; 50(6): 3445-3458, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36905102

RESUMO

BACKGROUND: Multiparametric magnetic resonance imaging (mp-MRI) is introduced and established as a noninvasive alternative for prostate cancer (PCa) detection and characterization. PURPOSE: To develop and evaluate a mutually communicated deep learning segmentation and classification network (MC-DSCN) based on mp-MRI for prostate segmentation and PCa diagnosis. METHODS: The proposed MC-DSCN can transfer mutual information between segmentation and classification components and facilitate each other in a bootstrapping way. For classification task, the MC-DSCN can transfer the masks produced by the coarse segmentation component to the classification component to exclude irrelevant regions and facilitate classification. For segmentation task, this model can transfer the high-quality localization information learned by the classification component to the fine segmentation component to mitigate the impact of inaccurate localization on segmentation results. Consecutive MRI exams of patients were retrospectively collected from two medical centers (referred to as center A and B). Two experienced radiologists segmented the prostate regions, and the ground truth of the classification refers to the prostate biopsy results. MC-DSCN was designed, trained, and validated using different combinations of distinct MRI sequences as input (e.g., T2-weighted and apparent diffusion coefficient) and the effect of different architectures on the network's performance was tested and discussed. Data from center A were used for training, validation, and internal testing, while another center's data were used for external testing. The statistical analysis is performed to evaluate the performance of the MC-DSCN. The DeLong test and paired t-test were used to assess the performance of classification and segmentation, respectively. RESULTS: In total, 134 patients were included. The proposed MC-DSCN outperforms the networks that were designed solely for segmentation or classification. Regarding the segmentation task, the classification localization information helped to improve the IOU in center A: from 84.5% to 87.8% (p < 0.01) and in center B: from 83.8% to 87.1% (p < 0.01), while the area under curve (AUC) of PCa classification was improved in center A: from 0.946 to 0.991 (p < 0.02) and in center B: from 0.926 to 0.955 (p < 0.01) as a result of the additional information provided by the prostate segmentation. CONCLUSION: The proposed architecture could effectively transfer mutual information between segmentation and classification components and facilitate each other in a bootstrapping way, thus outperforming the networks designed to perform only one task.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética/métodos
20.
Aging Male ; 26(1): 2159368, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36974926

RESUMO

INTRODUCTION: While robotic-assisted laparoscopic radical prostatectomy (RRP) is a standard mode for localized prostate cancer (PC), the risk of complications in older patients with chronic diseases and complex medical conditions can be a deterrent to surgery. Surgical and medical co-management (SMC) is a new strategy to improve patients' healthcare outcomes in surgical settings. METHODS: We reviewed the clinical data of older patients with chronic diseases who were cared for with SMC undergoing RRP in our hospital in the past 3 years and compared them with the clinical data from the general urology ward. Preoperative conditions and related indicators of recovery, and incidence of postoperative complications with the Clavien Grade System were compared between these two groups. RESULTS: The indicators of recovery were significantly better, and the incidence rates of complications were significantly reduced in the SMC group at grades I-IV (p < 0.05), as compared to the general urology ward group. CONCLUSIONS: The provision of care by SMC for older patients focused on early identification, comorbidity management, preoperative optimization, and collaborative management would significantly improve surgical outcomes. The SMC strategy is worthy of further clinical promotion in RRP treatment in older men with chronic diseases and complex medical conditions.


Assuntos
Laparoscopia , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Robótica , Masculino , Humanos , Idoso , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Prostatectomia/efeitos adversos , Neoplasias da Próstata/cirurgia , Laparoscopia/efeitos adversos , Resultado do Tratamento , Doença Crônica
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