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1.
BMC Ophthalmol ; 24(1): 361, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169342

RESUMO

PURPOSE: The primary objective of this study was to identify predictive factors linked to the normalization of thyroid-stimulating immunoglobulin (TSI) levels in patients diagnosed with active, moderate-to-severe Graves' orbitopathy (GO). The study also tracked the longitudinal changes in TSI levels over a 36-month period following treatment. METHODS: The study population consisted of individuals who were recently diagnosed with active, moderate-to-severe GO and received a 12-week course of intravenous methylprednisolone (IVMP) treatment. A subgroup of patients who did not respond to the initial treatment received an additional 20 Gy of radiation therapy (RTx). TSI levels were monitored at the time of diagnosis, after treatment, and subsequently every 6 months for 36 months. Normalization was defined as a TSI level below 140%. Patients were divdied into two groups with success and failure group depending on whether TSI became normal or not. RESULTS: Out of 83 patients, 36 (43.4%) achieved normalized TSI levels within two years post-IVMP treatment. Lower initial TSI levels (< 425%), absence of additional RTx, and early treatment initiation were associated with a higher likelihood of TSI normalization (P = 0.035, P = 0.028, P < 0.001, respectively). Notably, significant differences in TSI level reduction were observed from 18 months post-treatment between the two groups (P = 0.031). A TSI cutoff value of 413% was identified as predictive for normalization at 24 months (P = 0.002). CONCLUSION: This study is the first to identify key factors that influence normalization of TSI levels in moderate-to-severe Graves' Orbitopathy. It highlights the importance of early treatment decisions, particularly for patients with initial TSI levels above 425%. Despite the treatment, less than half of the patients achieved TSI normalization within 24 months, underscoring the need for additional research to explore the relationship between TSI levels and the clinical manifestations of chronic GO.


Assuntos
Glucocorticoides , Oftalmopatia de Graves , Imunoglobulinas Estimuladoras da Glândula Tireoide , Metilprednisolona , Humanos , Oftalmopatia de Graves/tratamento farmacológico , Oftalmopatia de Graves/diagnóstico , Oftalmopatia de Graves/sangue , Feminino , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto , Metilprednisolona/uso terapêutico , Metilprednisolona/administração & dosagem , Glucocorticoides/uso terapêutico , Imunoglobulinas Estimuladoras da Glândula Tireoide/sangue , Estudos Longitudinais , Seguimentos , Idoso , Índice de Gravidade de Doença , Estudos Retrospectivos
2.
Int J Mol Sci ; 25(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39062781

RESUMO

Due to their inhibition of acetylcholinesterase, organophosphates are among the most toxic of chemicals. Pralidoxime (a.k.a 2-PAM) is the only acetylcholinesterase reactivator approved in the U.S., but 2-PAM only poorly traverses the blood-brain barrier. Previously, we have demonstrated that scL-2PAM, a nanoformulation designed to enter the brain via receptor-mediated transcytosis, is superior to unencapsulated 2-PAM for reactivating brain acetylcholinesterase, ameliorating cholinergic crisis, and improving survival rates for paraoxon-exposed mice. Here, we employ histology and transcriptome analyses to assess the ability of scL-2PAM to prevent neurological sequelae including microglial activation, expression of inflammatory cytokines, and ultimately loss of neurons in mice surviving paraoxon exposures. Levels of the mRNA encoding chemokine ligand 2 (CCL2) were significantly upregulated after paraoxon exposures, with CCL2 mRNA levels in the brain correlating well with the intensity and duration of cholinergic symptoms. Our nanoformulation of 2-PAM was found to be superior to unencapsulated 2-PAM in reducing the levels of the CCL2 transcript. Moreover, brain histology revealed that scL-2PAM was more effective than unencapsulated 2-PAM in preventing microglial activation and the subsequent loss of neurons. Thus, scL-2PAM appears to be a new and improved countermeasure for reducing neuroinflammation and mitigating brain damage in survivors of organophosphate exposures.


Assuntos
Inibidores da Colinesterase , Doenças Neuroinflamatórias , Neurônios , Paraoxon , Animais , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Inibidores da Colinesterase/farmacologia , Paraoxon/toxicidade , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Quimiocina CCL2/metabolismo , Quimiocina CCL2/genética , Microglia/efeitos dos fármacos , Microglia/metabolismo , Masculino , Organofosfatos/farmacologia , Acetilcolinesterase/metabolismo , Camundongos Endogâmicos C57BL
3.
Int J Nanomedicine ; 19: 5973-5993, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895149

RESUMO

Purpose: Atypical teratoid rhabdoid tumor (ATRT) is a deadly, fast-growing form of pediatric brain cancer with poor prognosis. Most ATRTs are associated with inactivation of SMARCB1, a subunit of the chromatin remodeling complex, which is involved in developmental processes. The recent identification of SMARCB1 as a tumor suppressor gene suggests that restoration of SMARCB1 could be an effective therapeutic approach. Methods: We tested SMARCB1 gene therapy in SMARCB1-deficient rhabdoid tumor cells using a novel tumor-targeted nanomedicine (termed scL-SMARCB1) to deliver wild-type SMARCB1. Our nanomedicine is a systemically administered immuno-lipid nanoparticle that can actively cross the blood-brain barrier via transferrin receptor-mediated transcytosis and selectively target tumor cells via transferrin receptor-mediated endocytosis. We studied the antitumor activity of the scL-SMARCB1 nanocomplex either as a single agent or in combination with traditional treatment modalities in preclinical models of SMARCB1-deficient ATRT. Results: Restoration of SMARCB1 expression by the scL-SMARCB1 nanocomplex blocked proliferation, and induced senescence and apoptosis in ATRT cells. Systemic administration of the scL-SMARCB1 nanocomplex demonstrated antitumor efficacy as monotherapy in mice bearing ATRT xenografts, where the expression of exogenous SMARCB1 modulates MYC-target genes. scL-SMARCB1 demonstrated even greater antitumor efficacy when combined with either cisplatin-based chemotherapy or radiation therapy, resulting in significantly improved survival of ATRT-bearing mice. Conclusion: Collectively, our data suggest that restoring SMARCB1 function via the scL-SMARCB1 nanocomplex may lead to therapeutic benefits in ATRT patients when combined with traditional chemoradiation therapies.


Assuntos
Terapia Genética , Nanomedicina , Nanopartículas , Tumor Rabdoide , Proteína SMARCB1 , Animais , Proteína SMARCB1/genética , Tumor Rabdoide/genética , Tumor Rabdoide/terapia , Tumor Rabdoide/tratamento farmacológico , Terapia Genética/métodos , Camundongos , Linhagem Celular Tumoral , Nanopartículas/química , Humanos , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/genética , Modelos Animais de Doenças , Teratoma/terapia , Teratoma/genética , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Lipossomos
4.
Sci Adv ; 10(18): eadl6409, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701215

RESUMO

Ultrafast photoinduced melting provides an essential platform for studying nonequilibrium phase transitions by linking the kinetics of electron dynamics to ionic motions. Knowledge of dynamic balance in their energetics is essential to understanding how the ionic reaction is influenced by femtosecond photoexcited electrons with notable time lag depending on reaction mechanisms. Here, by directly imaging fluctuating density distributions and evaluating the ionic pressure and Gibbs free energy from two-temperature molecular dynamics that verified experimental results, we uncovered that transient ionic pressure, triggered by photoexcited electrons, controls the overall melting kinetics. In particular, ultrafast nonequilibrium melting can be described by the reverse nucleation process with voids as nucleation seeds. The strongly driven solid-to-liquid transition of metallic gold is successfully explained by void nucleation facilitated by photoexcited electron-initiated ionic pressure, establishing a solid knowledge base for understanding ultrafast nonequilibrium kinetics.

5.
Nat Chem ; 16(5): 693-699, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38528103

RESUMO

Crystalline systems consisting of small-molecule building blocks have emerged as promising materials with diverse applications. It is of great importance to characterize not only their static structures but also the conversion of their structures in response to external stimuli. Femtosecond time-resolved crystallography has the potential to probe the real-time dynamics of structural transitions, but, thus far, this has not been realized for chemical reactions in non-biological crystals. In this study, we applied time-resolved serial femtosecond crystallography (TR-SFX), a powerful technique for visualizing protein structural dynamics, to a metal-organic framework, consisting of Fe porphyrins and hexazirconium nodes, and elucidated its structural dynamics. The time-resolved electron density maps derived from the TR-SFX data unveil trifurcating structural pathways: coherent oscillatory movements of Zr and Fe atoms, a transient structure with the Fe porphyrins and Zr6 nodes undergoing doming and disordering movements, respectively, and a vibrationally hot structure with isotropic structural disorder. These findings demonstrate the feasibility of using TR-SFX to study chemical systems.

6.
J Synchrotron Radiat ; 31(Pt 3): 469-477, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517754

RESUMO

Various X-ray techniques are employed to investigate specimens in diverse fields. Generally, scattering and absorption/emission processes occur due to the interaction of X-rays with matter. The output signals from these processes contain structural information and the electronic structure of specimens, respectively. The combination of complementary X-ray techniques improves the understanding of complex systems holistically. In this context, we introduce a multiplex imaging instrument that can collect small-/wide-angle X-ray diffraction and X-ray emission spectra simultaneously to investigate morphological information with nanoscale resolution, crystal arrangement at the atomic scale and the electronic structure of specimens.

7.
Int J Nanomedicine ; 19: 307-326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38229703

RESUMO

Introduction: Organophosphates are among the deadliest of known chemicals based on their ability to inactivate acetylcholinesterase in neuromuscular junctions and synapses of the central and peripheral nervous systems. The consequent accumulation of acetylcholine can produce severe acute toxicities and death. Oxime antidotes act by reactivating acetylcholinesterase with the only such reactivator approved for use in the United States being 2-pyridine aldoxime methyl chloride (a.k.a., pralidoxime or 2-PAM). However, this compound does not cross the blood-brain barrier readily and so is limited in its ability to reactivate acetylcholinesterase in the brain. Methods: We have developed a novel formulation of 2-PAM by encapsulating it within a nanocomplex designed to cross the blood-brain barrier via transferrin receptor-mediated transcytosis. This nanocomplex (termed scL-2PAM) has been subjected to head-to-head comparisons with unencapsulated 2-PAM in mice exposed to paraoxon, an organophosphate with anticholinesterase activity. Results and Discussion: In mice exposed to a sublethal dose of paraoxon, scL-2PAM reduced the extent and duration of cholinergic symptoms more effectively than did unencapsulated 2-PAM. The scL-2PAM formulation was also more effective than unencapsulated 2-PAM in rescuing mice from death after exposure to otherwise-lethal levels of paraoxon. Improved survival rates in paraoxon-exposed mice were accompanied by a higher degree of reactivation of brain acetylcholinesterase. Conclusion: Our data indicate that scL-2PAM is superior to the currently used form of 2-PAM in terms of both mitigating paraoxon toxicity in mice and reactivating acetylcholinesterase in their brains.


Assuntos
Inibidores da Colinesterase , Reativadores da Colinesterase , Paraoxon , Compostos de Pralidoxima , Animais , Camundongos , Acetilcolinesterase/metabolismo , Encéfalo/metabolismo , Inibidores da Colinesterase/toxicidade , Reativadores da Colinesterase/farmacologia , Reativadores da Colinesterase/química , Organofosfatos , Oximas/farmacologia , Oximas/química , Paraoxon/toxicidade , Paraoxon/química , Compostos de Pralidoxima/química , Compostos de Pralidoxima/farmacologia
8.
J Crohns Colitis ; 18(1): 47-53, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-37523193

RESUMO

BACKGROUND AND AIMS: Crohn's disease [CD] has a complex polygenic aetiology with high heritability. There is ongoing effort to identify novel variants associated with susceptibility to CD through a genome-wide association study [GWAS] in large Korean populations. METHODS: Genome-wide variant data from 902 Korean patients with CD and 72 179 controls were used to assess the genetic associations in a meta-analysis with previous Korean GWAS results from 1621 patients with CD and 4419 controls. Epistatic interactions between CD-risk variants of interest were tested using a multivariate logistic regression model with an interaction term. RESULTS: We identified two novel genetic associations with the risk of CD near ZBTB38 and within the leukocyte immunoglobulin-like receptor [LILR] gene cluster [p < 5 × 10-8], with highly consistent effect sizes between the two independent Korean cohorts. CD-risk variants in the LILR locus are known quantitative trait loci [QTL] for multiple LILR genes, of which LILRB2 directly interacts with various ligands including MHC class I molecules. The LILR lead variant exhibited a significant epistatic interaction with CD-associated regulatory variants for TAP2 involved in the antigen presentation of MHC class I molecules [p = 4.11 × 10-4], showing higher CD-risk effects of the TAP2 variant in individuals carrying more risk alleles of the LILR lead variant (odds ratio [OR] = 0.941, p = 0.686 in non-carriers; OR = 1.45, p = 2.51 × 10-4 in single-copy carriers; OR = 2.38, p = 2.76 × 10-6 in two-copy carriers). CONCLUSIONS: This study demonstrated that genetic variants at two novel susceptibility loci and the epistatic interaction between variants in LILR and TAP2 loci confer a risk of CD.


Assuntos
Doença de Crohn , Humanos , Doença de Crohn/genética , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Família Multigênica , Antígenos de Histocompatibilidade Classe I/genética , Imunoglobulinas , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética
9.
Sci Adv ; 9(50): eadi6096, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100581

RESUMO

Giant impact-driven redox processes in the atmosphere and magma ocean played crucial roles in the evolution of Earth. However, because of the absence of rock records from that time, understanding these processes has proven challenging. Here, we present experimental results that simulate the giant impact-driven reactions between iron and volatiles (H2O and CO2) using x-ray free electron laser (XFEL) as fast heat pump and structural probe. Under XFEL pump, iron is oxidized to wüstite (FeO), while volatiles are reduced to H2 and CO. Furthermore, iron oxidation proceeds into formation of hydrides (γ-FeHx) and siderite (FeCO3), implying redox boundary near 300-km depth. Through quantitative analysis on reaction products, we estimate the volatile and FeO budgets in bulk silicate Earth, supporting the Theia hypothesis. Our findings shed light on the fast and short-lived process that led to reduced atmosphere, required for the emergence of prebiotic organic molecules in the early Earth.

10.
IUCrJ ; 10(Pt 6): 656-661, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37903100

RESUMO

X-ray structural science is undergoing a revolution driven by the emergence of X-ray Free-electron Laser (XFEL) facilities. The structures of crystalline solids can now be studied on the picosecond time scale relevant to phonons, atomic vibrations which travel at acoustic velocities. In the work presented here, X-ray diffuse scattering is employed to characterize the time dependence of the liquid phase emerging from femtosecond laser-induced melting of polycrystalline gold thin films using an XFEL. In a previous analysis of Bragg peak profiles, we showed the supersonic disappearance of the solid phase and presented a model of pumped hot electrons carrying energy from the gold surface to scatter at internal grain boundaries. This generates melt fronts propagating relatively slowly into the crystal grains. By conversion of diffuse scattering to a partial X-ray pair distribution function, we demonstrate that it has the characteristic shape obtained by Fourier transformation of the measured F(Q). The diffuse signal fraction increases with a characteristic rise-time of 13 ps, roughly independent of the incident pump fluence and consequent final liquid fraction. This suggests the role of further melt-front nucleation processes beyond grain boundaries.

11.
Cancers (Basel) ; 15(19)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37835545

RESUMO

Colorectal cancers (CRC) are classified into consensus molecular subtypes (CMS) based on gene expression profiles. The revised classification system iCMS was proposed by considering intrinsic epithelial status, microsatellite instability (MSI), and fibrosis. This study aimed to provide molecular evidence for the adenoma-carcinoma sequence concept by examining CRC and synchronous adenomas using iCMS. Epithelial CMS cell proportion was estimated using CiberSortx, an in silico cell fractionation method that included CMS cell types among the reference cell types. A random forest (RF) model estimated the posterior probabilities of CMS classes, which were compared with the CiberSortx results. Gene expression profiles of the published iCMS signature panel were retrieved from our dataset and subjected to heatmap clustering for classification. Bulk RNA sequencing data were collected from 29 adenocarcinomas and 11 adenoma samples. CiberSortx showed all CRC contained either CMS2 or CMS3 as the major epithelial cancer cell type. The RF model classified approximately half of the CRC as CMS4, whereas CMS4 was hardly detected by CiberSortx. Because they were enriched with myofibroblasts as per the CiberSortx classification, we tentatively designated them as iCMS2-F/iCMS3-F. iCMS coupled with the application of an in silico cell fractionation method can provide the molecular dissection of CRC and adenoma.

12.
Sci Rep ; 13(1): 17573, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845245

RESUMO

The structures, strain fields, and defect distributions in solid materials underlie the mechanical and physical properties across numerous applications. Many modern microstructural microscopy tools characterize crystal grains, domains and defects required to map lattice distortions or deformation, but are limited to studies of the (near) surface. Generally speaking, such tools cannot probe the structural dynamics in a way that is representative of bulk behavior. Synchrotron X-ray diffraction based imaging has long mapped the deeply embedded structural elements, and with enhanced resolution, dark field X-ray microscopy (DFXM) can now map those features with the requisite nm-resolution. However, these techniques still suffer from the required integration times due to limitations from the source and optics. This work extends DFXM to X-ray free electron lasers, showing how the [Formula: see text] photons per pulse available at these sources offer structural characterization down to 100 fs resolution (orders of magnitude faster than current synchrotron images). We introduce the XFEL DFXM setup with simultaneous bright field microscopy to probe density changes within the same volume. This work presents a comprehensive guide to the multi-modal ultrafast high-resolution X-ray microscope that we constructed and tested at two XFELs, and shows initial data demonstrating two timing strategies to study associated reversible or irreversible lattice dynamics.

13.
Genomics Inform ; 21(3): e40, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37813636

RESUMO

Microbial community profiling using 16S rRNA amplicon sequencing allows for taxonomic characterization of diverse microorganisms. While amplicon sequence variant (ASV) methods are increasingly favored for their fine-grained resolution of sequence variants, they often discard substantial portions of sequencing reads during quality control, particularly in datasets with large number samples. We present a streamlined pipeline that integrates FastP for read trimming, HmmUFOtu for operational taxonomic units (OTU) clustering, Vsearch for chimera checking, and Kraken2 for taxonomic assignment. To assess the pipeline's performance, we reprocessed two published stool datasets of normal Korean populations: one with 890 and the other with 1,462 independent samples. In the first dataset, HmmUFOtu retained 93.2% of over 104 million read pairs after quality trimming, discarding chimeric or unclassifiable reads, while DADA2, a commonly used ASV method, retained only 44.6% of the reads. Nonetheless, both methods yielded qualitatively similar ß-diversity plots. For the second dataset, HmmUFOtu retained 89.2% of read pairs, while DADA2 retained a mere 18.4% of the reads. HmmUFOtu, being a closed-reference clustering method, facilitates merging separately processed datasets, with shared OTUs between the two datasets exhibiting a correlation coefficient of 0.92 in total abundance (log scale). While the first two dimensions of the ß-diversity plot exhibited a cohesive mixture of the two datasets, the third dimension revealed the presence of a batch effect. Our comparative evaluation of ASV and OTU methods within this streamlined pipeline provides valuable insights into their performance when processing large-scale microbial 16S rRNA amplicon sequencing data. The strengths of HmmUFOtu and its potential for dataset merging are highlighted.

14.
Int J Mol Sci ; 24(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37834250

RESUMO

We investigated whether the response to anti-tumor necrosis factor (anti-TNF) treatment varied according to inflammatory tissue characteristics in Crohn's disease (CD). Bulk RNA sequencing (RNA-seq) data were obtained from inflamed and non-inflamed tissues from 170 patients with CD. The samples were clustered based on gene expression profiles using principal coordinate analysis (PCA). Cellular heterogeneity was inferred using CiberSortx, with bulk RNA-seq data. The PCA results displayed two clusters of CD-inflamed samples: one close to (Inflamed_1) and the other far away (Inflamed_2) from the non-inflamed samples. Inflamed_1 was rich in anti-TNF durable responders (DRs), and Inflamed_2 was enriched in non-durable responders (NDRs). The CiberSortx results showed that the cell fraction of activated fibroblasts was six times higher in Inflamed_2 than in Inflamed_1. Validation with public gene expression datasets (GSE16879) revealed that the activated fibroblasts were enriched in NDRs over Next, we used DRs by 1.9 times pre-treatment and 7.5 times after treatment. Fibroblast activation protein (FAP) was overexpressed in the Inflamed_2 and was also overexpressed in the NDRs in both the RISK and GSE16879 datasets. The activation of fibroblasts may play a role in resistance to anti-TNF therapy. Characterizing fibroblasts in inflamed tissues at diagnosis may help to identify patients who are likely to respond to anti-TNF therapy.


Assuntos
Doença de Crohn , Humanos , Doença de Crohn/tratamento farmacológico , Doença de Crohn/genética , Doença de Crohn/metabolismo , Inibidores do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , RNA/metabolismo , Fibroblastos/metabolismo , Necrose/metabolismo
15.
Microorganisms ; 11(7)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37512838

RESUMO

Although gut microbiome dysbiosis has been associated with inflammatory bowel disease (IBD), the relationship between the oral microbiota and IBD remains poorly understood. This study aimed to identify unique microbiome patterns in saliva from IBD patients and explore potential oral microbial markers for differentiating Crohn's disease (CD) and ulcerative colitis (UC). A prospective cohort study recruited IBD patients (UC: n = 175, CD: n = 127) and healthy controls (HC: n = 100) to analyze their oral microbiota using 16S rRNA gene sequencing. Machine learning models (sparse partial least squares discriminant analysis (sPLS-DA)) were trained with the sequencing data to classify CD and UC. Taxonomic classification resulted in 4041 phylotypes using Kraken2 and the SILVA reference database. After quality filtering, 398 samples (UC: n = 175, CD: n = 124, HC: n = 99) and 2711 phylotypes were included. Alpha diversity analysis revealed significantly reduced richness in the microbiome of IBD patients compared to healthy controls. The sPLS-DA model achieved high accuracy (mean accuracy: 0.908, and AUC: 0.966) in distinguishing IBD vs. HC, as well as good accuracy (0.846) and AUC (0.923) in differentiating CD vs. UC. These findings highlight distinct oral microbiome patterns in IBD and provide insights into potential diagnostic markers.

16.
Nano Lett ; 23(4): 1481-1488, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36723175

RESUMO

Femtosecond laser pulses drive nonequilibrium phase transitions via reaction paths hidden in thermal equilibrium. This stimulates interest to understand photoinduced ultrafast melting processes, which remains incomplete due to challenges in resolving accompanied kinetics at the relevant space-time resolution. Here, by newly establishing a multiplexing femtosecond X-ray probe, we have successfully revealed ultrafast energy transfer processes in confined Au nanospheres. Real-time images of electron density distributions with the corresponding lattice structures elucidate that the energy transfer begins with subpicosecond melting at the specimen boundary earlier than the lattice thermalization, and proceeds by forming voids. Two temperature molecular dynamics simulations uncovered the presence of both heterogeneous melting with the melting front propagation from surface and grain boundaries and homogeneous melting with random melting seeds and nanoscale voids. Supported by experimental and theoretical results, we provide a comprehensive atomic-scale picture that accounts for the ultrafast laser-induced melting and evaporation kinetics.

17.
Microorganisms ; 12(1)2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38257863

RESUMO

Recent research has demonstrated the potential of fecal microbiome analysis using machine learning (ML) in the diagnosis of inflammatory bowel disease (IBD), mainly Crohn's disease (CD) and ulcerative colitis (UC). This study employed the sparse partial least squares discriminant analysis (sPLS-DA) ML technique to develop a robust prediction model for distinguishing among CD, UC, and healthy controls (HCs) based on fecal microbiome data. Using data from multicenter cohorts, we conducted 16S rRNA gene sequencing of fecal samples from patients with CD (n = 671) and UC (n = 114) while forming an HC cohort of 1462 individuals from the Kangbuk Samsung Hospital Healthcare Screening Center. A streamlined pipeline based on HmmUFOTU was used. After a series of filtering steps, 1517 phylotypes and 1846 samples were retained for subsequent analysis. After 100 rounds of downsampling with age, sex, and sample size matching, and division into training and test sets, we constructed two binary prediction models to distinguish between IBD and HC and CD and UC using the training set. The binary prediction models exhibited high accuracy and area under the curve (for differentiating IBD from HC (mean accuracy, 0.950; AUC, 0.992) and CD from UC (mean accuracy, 0.945; AUC, 0.988)), respectively, in the test set. This study underscores the diagnostic potential of an ML model based on sPLS-DA, utilizing fecal microbiome analysis, highlighting its ability to differentiate between IBD and HC and distinguish CD from UC.

18.
J Imaging ; 8(12)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36547492

RESUMO

To train an automatic brain tumor segmentation model, a large amount of data is required. In this paper, we proposed a strategy to overcome the limited amount of clinically collected magnetic resonance image (MRI) data regarding meningiomas by pre-training a model using a larger public dataset of MRIs of gliomas and augmenting our meningioma training set with normal brain MRIs. Pre-operative MRIs of 91 meningioma patients (171 MRIs) and 10 non-meningioma patients (normal brains) were collected between 2016 and 2019. Three-dimensional (3D) U-Net was used as the base architecture. The model was pre-trained with BraTS 2019 data, then fine-tuned with our datasets consisting of 154 meningioma MRIs and 10 normal brain MRIs. To increase the utility of the normal brain MRIs, a novel balanced Dice loss (BDL) function was used instead of the conventional soft Dice loss function. The model performance was evaluated using the Dice scores across the remaining 17 meningioma MRIs. The segmentation performance of the model was sequentially improved via the pre-training and inclusion of normal brain images. The Dice scores improved from 0.72 to 0.76 when the model was pre-trained. The inclusion of normal brain MRIs to fine-tune the model improved the Dice score; it increased to 0.79. When employing BDL as the loss function, the Dice score reached 0.84. The proposed learning strategy for U-net showed potential for use in segmenting meningioma lesions.

19.
Cells ; 11(21)2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36359830

RESUMO

Lung cancer is among the most common and lethal cancers and warrants novel therapeutic approaches to improving patient outcomes. Although immune checkpoint inhibitors (ICIs) have demonstrated substantial clinical benefits, most patients remain unresponsive to currently approved ICIs or develop resistance after initial response. Many ongoing clinical studies are investigating combination therapies to address the limited efficacy of ICIs. Here, we have assessed whether p53 gene therapy via a tumor-targeting nanomedicine (termed SGT-53) can augment anti-programmed cell death-1 (PD-1) immunotherapy to expand its use in non-responding patients. Using syngeneic mouse models of lung cancers that are resistant to anti-PD-1, we demonstrate that restoration of normal p53 function potentiates anti-PD-1 to inhibit tumor growth and prolong survival of tumor-bearing animals. Our data indicate that SGT-53 can restore effective immune responses against lung cancer cells by reducing immuno-suppressive cells (M2 macrophages and regulatory T cells) and by downregulating immunosuppressive molecules (e.g., galectin-1, a negative regulator of T cell activation and survival) while increasing activity of cytotoxic T cells. These results suggest that combining SGT-53 with anti-PD-1 immunotherapy could increase the fraction of lung cancer patients that responds to anti-PD-1 therapy and support evaluation of this combination particularly in patients with ICI-resistant lung cancers.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Camundongos , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptor de Morte Celular Programada 1/metabolismo , Proteína Supressora de Tumor p53/genética , Nanomedicina , Neoplasias Pulmonares/tratamento farmacológico , Antineoplásicos/farmacologia , Modelos Animais de Doenças , Terapia de Imunossupressão
20.
J Synchrotron Radiat ; 29(Pt 6): 1465-1479, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36345755

RESUMO

A Hanbury Brown and Twiss interferometry experiment based on second-order correlations was performed at the PAL-XFEL facility. The statistical properties of the X-ray radiation were studied within this experiment. Measurements were performed at the NCI beamline at 10 keV photon energy under various operation conditions: self-amplified spontaneous emission (SASE), SASE with a monochromator, and self-seeding regimes at 120 pC, 180 pC and 200 pC electron bunch charge. Statistical analysis showed short average pulse duration from 6 fs to 9 fs depending on the operational conditions. A high spatial degree of coherence of about 70-80% was determined in the spatial domain for the SASE beams with the monochromator and self-seeding regime of operation. The obtained values describe the statistical properties of the beams generated at the PAL-XFEL facility.

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