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1.
Drug Des Devel Ther ; 18: 2847-2868, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006190

RESUMO

Purpose: This study aimed to delineate the molecular processes underlying the therapeutic effects of berberine on UC by employing network pharmacology tactics, molecular docking, and dynamic simulations supported by empirical validations both in vivo and in vitro. Patients and Methods: We systematically screened potential targets and relevant pathways affected by berberine for UC treatment from comprehensive databases, including GeneCards, DisGeNET, and GEO. Molecular docking and simulation protocols were used to assess the interaction stability between berberine and its principal targets. The predictions were validated using both a DSS-induced UC mouse model and a lipopolysaccharide (LPS)-stimulated NCM460 cellular inflammation model. Results: Network pharmacology analysis revealed the regulatory effect of the TLR4/NF-κB/HIF-1α pathway in the ameliorative action of berberine in UC. Docking and simulation studies predicted the high-affinity interactions of berberine with pivotal targets: TLR4, NF-κB, HIF-1α, and the HIF inhibitor KC7F2. Moreover, in vivo analyses demonstrated that berberine attenuates clinical severity, as reflected by decreased disease activity index (DAI) scores, reduced weight loss, and mitigated intestinal inflammation in DSS-challenged mice. These outcomes include suppression of the proinflammatory cytokines IL-6 and TNF-α and downregulation of TLR4/NF-κB/HIF-1α mRNA and protein levels. Correspondingly, in vitro findings indicate that berberine decreases cellular inflammatory injury and suppresses TLR4/NF-κB/HIF-1α signaling, with notable effectiveness similar to that of the HIF-1α inhibitor KC7F2. Conclusion: Through network pharmacology analysis and experimental substantiation, this study confirmed that berberine enhances UC treatment outcomes by inhibiting the TLR4/NF-κB/HIF-1α axis, thereby mitigating inflammatory reactions and improving colonic pathology.


Assuntos
Berberina , Colite Ulcerativa , Biologia Computacional , Subunidade alfa do Fator 1 Induzível por Hipóxia , NF-kappa B , Receptor 4 Toll-Like , Berberina/farmacologia , Berberina/química , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Animais , Camundongos , Humanos , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Simulação de Acoplamento Molecular , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Masculino , Sulfato de Dextrana , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Farmacologia em Rede
2.
Artigo em Inglês | MEDLINE | ID: mdl-38949946

RESUMO

Previous knowledge distillation (KD) methods mostly focus on compressing network architectures, which is not thorough enough in deployment as some costs like transmission bandwidth and imaging equipment are related to the image size. Therefore, we propose Pixel Distillation that extends knowledge distillation into the input level while simultaneously breaking architecture constraints. Such a scheme can achieve flexible cost control for deployment, as it allows the system to adjust both network architecture and image quality according to the overall requirement of resources. Specifically, we first propose an input spatial representation distillation (ISRD) mechanism to transfer spatial knowledge from large images to student's input module, which can facilitate stable knowledge transfer between CNN and ViT. Then, a Teacher-Assistant-Student (TAS) framework is further established to disentangle pixel distillation into the model compression stage and input compression stage, which significantly reduces the overall complexity of pixel distillation and the difficulty of distilling intermediate knowledge. Finally, we adapt pixel distillation to object detection via an aligned feature for preservation (AFP) strategy for TAS, which aligns output dimensions of detectors at each stage by manipulating features and anchors of the assistant. Comprehensive experiments on image classification and object detection demonstrate the effectiveness of our method.

5.
BMJ Open ; 14(7): e081751, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960463

RESUMO

INTRODUCTION: Post-traumatic stress disorder (PTSD) is a prevalent and severe psychiatric disorder. Repetitive transcranial magnetic stimulation (rTMS) targeting the dorsolateral prefrontal cortex provides limited relief for symptoms of PTSD. This study will be conducted to validate the efficacy of MRI-guided rTMS in targeting the sites most closely associated with the amygdala for patients with PTSD. We hypothesise that the intervention will improve clinical symptoms by decreasing amygdala activity in patients. METHODS AND ANALYSIS: A randomised, double-blind, sham-controlled trial will be conducted. Forty-eight eligible patients with PTSD will be randomly assigned to receive either active or sham MRI-guided rTMS for 10 consecutive days after the initial MRI scans. MRI scans will be recollected at the end of the intervention. Clinical assessments will be performed at baseline, treatment day 5, treatment day 10, and 2 weeks, 4 weeks, 8 weeks after completion of the intervention to monitor changes in clinical symptoms. The primary assessment outcome is the change in PTSD symptoms between baseline and treatment day 10, as measured by the PTSD Checklist for DSM-5. Repeated measures analysis of variance will be performed using statistical software SPSS V.26.0. The significance level will be set at 0.05. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Ethics Committee of Xijing Hospital in Xi'an, China (KY20222176-X-1), and the trial has been registered on ClinicalTrials.gov. The findings of this trial will be disseminated at academic conferences or published in peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: NCT05544110.


Assuntos
Tonsila do Cerebelo , Imageamento por Ressonância Magnética , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos de Estresse Pós-Traumáticos , Estimulação Magnética Transcraniana , Humanos , Transtornos de Estresse Pós-Traumáticos/terapia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Estimulação Magnética Transcraniana/métodos , Imageamento por Ressonância Magnética/métodos , Método Duplo-Cego , Tonsila do Cerebelo/diagnóstico por imagem , Adulto , Masculino , Pessoa de Meia-Idade , Feminino , Resultado do Tratamento , Adulto Jovem
7.
Heart Rhythm ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901520

RESUMO

BACKGROUND: The association between serum potassium and atrial fibrillation (AF) recurrence after catheter ablation remains unclear. OBJECTIVE: To investigate whether preprocedural serum potassium influences AF recurrence in patients underwent catheter ablation. METHODS: We used data of AF patients who underwent de novo catheter ablation from the prospective Chinese Atrial Fibrillation Registry Study (CAFR). Patients with prior ablation and without baseline serum potassium were excluded. The primary outcome was 1-year AF recurrence after 3-month blanking period from the ablation. Restricted cubic spline and Cox proportional models were used to compare outcomes across serum potassium categories. RESULTS: A total of 4838 AF patients with de novo catheter ablation was enrolled. At 1 year, AF recurrence occurred in 1347 (27.8%) patients. The relationship between preprocedural serum potassium and 1-year AF recurrence after ablation presented as U-shape (P for nonlinear = 0.048). Compared with the group of serum potassium within 4.41-4.60 mmol/L, the risk of AF recurrence increased significantly in the lowest serum potassium group (≤4.00 mmol/L) after multivariate analysis (HR 1.26, 95% CI 1.06-1.51, P = 0.010). Other categories with lower or higher serum potassium levels including 4.01-4.20 mmol/L (HR=1.18), 4.21-4.40 mmol/L (HR=1.16), 4.61-4.80 mmol/L (HR=1.07) and ≥4.81 mmol/L (HR=1.11) showed nonsignificant higher recurrence risk. CONCLUSIONS: The relationship between preprocedural potassium and AF recurrence was U-shaped, with an optimal potassium range (4.41-4.60 mmol/L). Lower potassium level is associated with increased AF recurrence risk after catheter ablation.

8.
Curr Med Imaging ; 20(1): e15734056304038, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38874042

RESUMO

OBJECTIVES: This study aimed to investigate the pancreatic morphology and clinical characteristics to predict risk factors of type 2 diabetes mellitus (T2DM) based on magnetic resonance imaging. METHODS: A total of 89 patients (T2DM group) and 68 healthy controls (HC group) were included. The T2DM group was divided into a long-term T2DM group and a short-term T2DM group according to whether the illness duration was more than 5 years. The clinical characteristics were collected, including sex, age, fasting plasma glucose, glycosylated hemoglobin, and lipoproteins. The pancreatic morphological characteristics, including the diameters of the pancreatic head, neck, body, and tail, the angle of the pancreaticobiliary junction (APJ), and the types of pancreaticobiliary junction were measured. The risk prediction model was established by logistic regression analysis. RESULTS: In the long-term T2DM group, the pancreatic diameters were smaller than the other two groups. In the short-term T2DM group, the diameters of the pancreatic tail and body were smaller than the HC group. The APJ, very low-density lipoprotein, and triglyceride levels in the two T2DM groups were greater than the HC group, and the APJ of the short-term T2DM group was smaller than the long-term T2DM group. Pancreatic diameters showed a negative correlation with illness duration. Logistic regression analysis revealed pancreatic body diameter was a protective factor, and APJ was a risk factor for T2DM. Prediction model accuracy was 90.20%. CONCLUSIONS: The morphology of the pancreas is helpful to predict the risk of the onset of T2DM. The risk of onset of T2DM increases with smaller pancreatic body diameter and higher APJ.

.


Assuntos
Diabetes Mellitus Tipo 2 , Imageamento por Ressonância Magnética , Pâncreas , Humanos , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Estudos Transversais , Fatores de Risco , Adulto , Estudos de Casos e Controles , Idoso , Medição de Risco
9.
J Control Release ; 372: 522-530, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38897293

RESUMO

Cyanine derivatives are organic dyes widely used for optical imaging. However, their potential in longitudinal optoacoustic imaging and photothermal therapy remains limited due to challenges such as poor chemical stability, poor photostability, and low photothermal conversion. In this study, we present a new structural modification for cyanine dyes by introducing a strongly electron-withdrawing group (barbiturate), resulting in a new series of barbiturate-cyanine dyes (BC810, BC885, and BC1010) with suppressed fluorescence and enhanced stability. Furthermore, the introduction of BC1010 into block copolymers (PEG114-b-PCL60) induces aggregation-caused quenching, further boosting the photothermal performance. The photophysical properties of nanoparticles (BC1010-NPs) include their remarkably broad absorption range from 900 to 1200 nm for optoacoustic imaging, allowing imaging applications in NIR-I and NIR-II windows. The combined effect of these strategies, including improved photostability, enhanced nonradiative relaxation, and aggregation-caused quenching, enables the detection of optoacoustic signals with high sensitivity and effective photothermal treatment of in vivo tumor models when BC1010-NPs are administered before irradiation with a 1064 nm laser. This research introduces a barbiturate-functionalized cyanine derivative with optimal properties for efficient optoacoustics-guided theranostic applications. This new compound holds significant potential for biomedical use, facilitating advancements in optoacoustic-guided diagnostic and therapeutic approaches.

10.
BMC Med ; 22(1): 269, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926749

RESUMO

BACKGROUND: In the USA, the prolonged effective survival of cancer population has brought significant attention to the rising risk of cardiometabolic morbidity and mortality in this population. This heightened risk underscores the urgent need for research into effective pharmacological interventions for cancer survivors. Notably, metformin, a well-known metabolic regulator with pleiotropic effects, has shown protective effects against cardiometabolic disorders in diabetic individuals. Despite these promising indications, evidence supporting its efficacy in improving cardiometabolic outcomes in cancer survivors remains scarce. METHODS: A prospective cohort was established using a nationally representative sample of cancer survivors enrolled in the US National Health and Nutrition Examination Survey (NHANES), spanning 2003 to 2018. Outcomes were derived from patient interviews, physical examinations, and public-access linked mortality archives up to 2019. The Oxidative Balance Score was utilized to assess participants' levels of oxidative stress. To evaluate the correlations between metformin use and the risk of cardiometabolic diseases and related mortality, survival analysis of cardiometabolic mortality was performed by Cox proportional hazards model, and cross-sectional analysis of cardiometabolic diseases outcomes was performed using logistic regression models. Interaction analyses were conducted to explore the specific pharmacological mechanism of metformin. RESULTS: Among 3995 cancer survivors (weighted population, 21,671,061, weighted mean [SE] age, 62.62 [0.33] years; 2119 [53.04%] females; 2727 [68.26%] Non-Hispanic White individuals), 448 reported metformin usage. During the follow-up period of up to 17 years (median, 6.42 years), there were 1233 recorded deaths, including 481 deaths from cardiometabolic causes. Multivariable models indicated that metformin use was associated with a lower risk of all-cause (hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.47-0.81) and cardiometabolic (HR, 0.65; 95% CI, 0.44-0.97) mortality compared with metformin nonusers. Metformin use was also correlated with a lower risk of total cardiovascular disease (odds ratio [OR], 0.41; 95% CI, 0.28-0.59), stroke (OR, 0.44; 95% CI, 0.26-0.74), hypertension (OR, 0.27; 95% CI, 0.14-0.52), and coronary heart disease (OR, 0.41; 95% CI, 0.21-0.78). The observed inverse associations were consistent across subgroup analyses in four specific cancer populations identified as cardiometabolic high-risk groups. Interaction analyses suggested that metformin use as compared to non-use may counter-balance oxidative stress. CONCLUSIONS: In this cohort study involving a nationally representative population of US cancer survivors, metformin use was significantly correlated with a lower risk of cardiometabolic diseases, all-cause mortality, and cardiometabolic mortality.


Assuntos
Sobreviventes de Câncer , Doenças Cardiovasculares , Metformina , Humanos , Metformina/uso terapêutico , Feminino , Masculino , Sobreviventes de Câncer/estatística & dados numéricos , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Doenças Cardiovasculares/mortalidade , Estudos Prospectivos , Hipoglicemiantes/uso terapêutico , Idoso , Estudos Transversais , Inquéritos Nutricionais , Estudos de Coortes , Neoplasias/mortalidade
11.
Sci Adv ; 10(24): eado2037, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875326

RESUMO

Activatable near-infrared (NIR) imaging in the NIR-II range is crucial for deep tissue bioanalyte tracking. However, designing such probes remains challenging due to the limited availability of general chemical strategies. Here, we introduced a foundational platform for activatable probes, using analyte-triggered smart modulation of the π-conjugation system of a NIR-II-emitting rhodamine hybrid. By tuning the nucleophilicity of the ortho-carboxy moiety, we achieved an electronic effect termed "firm-push-to-open and light-push-to-lock," which enables complete spirocyclization of the probe before sensing and allows for efficient zwitterion formation when the light-pushing aniline carbamate trigger is transformed into a firm-pushing aniline. This platform produces dual-modality NIR-II imaging probes with ~50-fold fluorogenic and activatable photoacoustic signals in live mice, surpassing reported probes with generally below 10-fold activatable signals. Demonstrating generality, we successfully designed probes for hydrogen peroxide (H2O2) and hydrogen sulfide (H2S). We envision a widespread adoption of the chemical platform for designing activatable NIR-II probes across diverse applications.


Assuntos
Corantes Fluorescentes , Animais , Camundongos , Corantes Fluorescentes/química , Imagem Óptica/métodos , Peróxido de Hidrogênio/química , Humanos , Sulfeto de Hidrogênio/análise , Sulfeto de Hidrogênio/química , Técnicas Fotoacústicas/métodos , Raios Infravermelhos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Rodaminas/química
12.
Sci Rep ; 14(1): 14145, 2024 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898042

RESUMO

This study probes the utility of biomarkers for microsatellite instability (MSI) detection and elucidates the molecular dynamics propelling colorectal cancer (CRC) progression. We synthesized a primer panel targeting 725 MSI loci, informed by The Cancer Genome Atlas (TCGA) and ancillary databases, to construct an amplicon library for next-generation sequencing (NGS). K-means clustering facilitated the distillation of 8 prime MSI loci, including activin A receptor type 2A (ACVR2A). Subsequently, we explored ACVR2A's influence on CRC advancement through in vivo tumor experiments and hematoxylin-eosin (HE) staining. Transwell assays gauged ACVR2A's role in CRC cell migration and invasion, while colony formation assays appraised cell proliferation. Western blotting illuminated the impact of ACVR2A suppression on CRC's PI3K/AKT/mTOR pathway protein expressions under hypoxia. Additionally, ACVR2A's influence on CRC-induced angiogenesis was quantified via angiogenesis assays. K-means clustering of NGS data pinpointed 32 MSI loci specific to tumor and DNA mismatch repair deficiency (dMMR) tissues. ACVR2A emerged as a pivotal biomarker, discerning MSI-H tissues with 90.97% sensitivity. A curated 8-loci set demonstrated 100% sensitivity and specificity for MSI-H detection in CRC. In vitro analyses corroborated ACVR2A's critical role, revealing its suppression of CRC proliferation, migration, and invasion. Moreover, ACVR2A inhibition under CRC-induced hypoxia markedly escalated MMP3, CyclinA, CyclinD1, and HIF1α protein expressions, alongside angiogenesis, by triggering the PI3K/AKT/mTOR cascade. The 8-loci ensemble stands as the optimal marker for MSI-H identification in CRC. ACVR2A, a central element within this group, deters CRC progression, while its suppression amplifies PI3K/AKT/mTOR signaling and angiogenesis under hypoxic stress.


Assuntos
Receptores de Activinas Tipo II , Movimento Celular , Neoplasias Colorretais , Progressão da Doença , Instabilidade de Microssatélites , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Humanos , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo , Animais , Movimento Celular/genética , Camundongos , Linhagem Celular Tumoral , Proliferação de Células/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Transdução de Sinais , Masculino , Sequenciamento de Nucleotídeos em Larga Escala , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética
13.
Sci Total Environ ; 945: 173896, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38880138

RESUMO

Urban traffic congestion has resulted in several adverse outcomes, including reduced traffic efficiency, increased noise pollution, and heightened exhaust emissions. It has also emerged as a significant indicator of urban health concerns. This article primarily delves into an examination of the pollution stemming from congestion. To accomplish this, the study focuses on two specific aspects of congestion measurement: long-term spatial constraints (limited travel routes) and short-term time delays (time wasted due to congestion). Expanding on this, the article explores the potential solutions to mitigate pollution effects through measures such as optimizing space utilization through public transportation systems like subways and strategically scheduling travel during holidays. These considerations are incorporated within the article's scope. Additionally, in order to address endogeneity concerns, the research conducts instrumental variable effectiveness tests from both temporal and spatial perspectives. The outcomes highlight the degradation of air quality and the increase in total traffic congestion in both the long and short term, while also indicating the presence of genuine methods to alleviate these issues. Consequently, effective collaborative efforts for prevention and control are imperative to combat environmental and traffic pollution. Moreover, optimizing sustainable urban development plans to enhance land utilization plays a pivotal role in minimizing the external costs associated with long-distance commuting.

14.
Nat Genet ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849613

RESUMO

Long interspersed nuclear element-1 (LINE-1 or L1) is a retrotransposon group that constitutes 17% of the human genome and shows variable expression across cell types. However, the control of L1 expression and its function in gene regulation are incompletely understood. Here we show that L1 transcription activates long-range gene expression. Genome-wide CRISPR-Cas9 screening using a reporter driven by the L1 5' UTR in human cells identifies functionally diverse genes affecting L1 expression. Unexpectedly, altering L1 expression by knockout of regulatory genes impacts distant gene expression. L1s can physically contact their distal target genes, with these interactions becoming stronger upon L1 activation and weaker when L1 is silenced. Remarkably, L1s contact and activate genes essential for zygotic genome activation (ZGA), and L1 knockdown impairs ZGA, leading to developmental arrest in mouse embryos. These results characterize the regulation and function of L1 in long-range gene activation and reveal its importance in mammalian ZGA.

15.
Acta Pharm Sin B ; 14(6): 2786-2789, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38828158

RESUMO

The current status of clinical trials utilizing nanoparticle drug delivery system (NDDS) for brain tumors was summarized.Image 1.

16.
Research (Wash D C) ; 7: 0351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38867720

RESUMO

The tricarboxylic acid (TCA) cycle is capable of providing sufficient energy for the physiological activities under aerobic conditions. Although tumor metabolic reprogramming places aerobic glycolysis in a dominant position, the TCA cycle remains indispensable for tumor cells as a hub for the metabolic linkage and interconversion of glucose, lipids, and certain amino acids. TCA intermediates such as citrate, α-ketoglutarate, succinate, and fumarate are altered in tumors, and they regulate the tumor metabolism, signal transduction, and immune environment to affect tumorigenesis and tumor progression. This article provides a comprehensive review of the modifications occurring in tumor cells in relation to the intermediates of the TCA cycle, which affects tumor pathogenesis and current therapeutic strategy for therapy through targeting TCA cycle in cancer cells.

17.
Front Immunol ; 15: 1358036, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690262

RESUMO

Background: It remains unclear whether BPIV3 infection leads to stress granules formation and whether G3BP1 plays a role in this process and in viral replication. This study aims to clarify the association between BPIV3 and stress granules, explore the effect of G3BP1 on BPIV3 replication, and provide significant insights into the mechanisms by which BPIV3 evades the host's antiviral immunity to support its own survival. Methods: Here, we use Immunofluorescence staining to observe the effect of BPIV3 infection on the assembly of stress granules. Meanwhile, the expression changes of eIF2α and G3BP1 were determined. Overexpression or siRNA silencing of intracellular G3BP1 levels was examined for its regulatory control of BPIV3 replication. Results: We identify that the BPIV3 infection elicited phosphorylation of the eIF2α protein. However, it did not induce the assembly of stress granules; rather, it inhibited the formation of stress granules and downregulated the expression of G3BP1. G3BP1 overexpression facilitated the formation of stress granules within cells and hindered viral replication, while G3BP1 knockdown enhanced BPIV3 expression. Conclusion: This study suggest that G3BP1 plays a crucial role in BPIV3 suppressing stress granule formation and viral replication.


Assuntos
DNA Helicases , Proteínas de Ligação a Poli-ADP-Ribose , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA , Grânulos de Estresse , Replicação Viral , Animais , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , DNA Helicases/metabolismo , DNA Helicases/genética , RNA Helicases/metabolismo , RNA Helicases/genética , Grânulos de Estresse/metabolismo , Bovinos , Fator de Iniciação 2 em Eucariotos/metabolismo , Infecções por Respirovirus/imunologia , Infecções por Respirovirus/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Fosforilação , Linhagem Celular , Grânulos Citoplasmáticos/metabolismo
18.
J Biomed Opt ; 29(9): 093503, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38715717

RESUMO

Significance: Hyperspectral dark-field microscopy (HSDFM) and data cube analysis algorithms demonstrate successful detection and classification of various tissue types, including carcinoma regions in human post-lumpectomy breast tissues excised during breast-conserving surgeries. Aim: We expand the application of HSDFM to the classification of tissue types and tumor subtypes in pre-histopathology human breast lumpectomy samples. Approach: Breast tissues excised during breast-conserving surgeries were imaged by the HSDFM and analyzed. The performance of the HSDFM is evaluated by comparing the backscattering intensity spectra of polystyrene microbead solutions with the Monte Carlo simulation of the experimental data. For classification algorithms, two analysis approaches, a supervised technique based on the spectral angle mapper (SAM) algorithm and an unsupervised technique based on the K-means algorithm are applied to classify various tissue types including carcinoma subtypes. In the supervised technique, the SAM algorithm with manually extracted endmembers guided by H&E annotations is used as reference spectra, allowing for segmentation maps with classified tissue types including carcinoma subtypes. Results: The manually extracted endmembers of known tissue types and their corresponding threshold spectral correlation angles for classification make a good reference library that validates endmembers computed by the unsupervised K-means algorithm. The unsupervised K-means algorithm, with no a priori information, produces abundance maps with dominant endmembers of various tissue types, including carcinoma subtypes of invasive ductal carcinoma and invasive mucinous carcinoma. The two carcinomas' unique endmembers produced by the two methods agree with each other within <2% residual error margin. Conclusions: Our report demonstrates a robust procedure for the validation of an unsupervised algorithm with the essential set of parameters based on the ground truth, histopathological information. We have demonstrated that a trained library of the histopathology-guided endmembers and associated threshold spectral correlation angles computed against well-defined reference data cubes serve such parameters. Two classification algorithms, supervised and unsupervised algorithms, are employed to identify regions with carcinoma subtypes of invasive ductal carcinoma and invasive mucinous carcinoma present in the tissues. The two carcinomas' unique endmembers used by the two methods agree to <2% residual error margin. This library of high quality and collected under an environment with no ambient background may be instrumental to develop or validate more advanced unsupervised data cube analysis algorithms, such as effective neural networks for efficient subtype classification.


Assuntos
Algoritmos , Neoplasias da Mama , Mastectomia Segmentar , Microscopia , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Feminino , Mastectomia Segmentar/métodos , Microscopia/métodos , Mama/diagnóstico por imagem , Mama/patologia , Mama/cirurgia , Imageamento Hiperespectral/métodos , Margens de Excisão , Método de Monte Carlo , Processamento de Imagem Assistida por Computador/métodos
19.
Materials (Basel) ; 17(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38730793

RESUMO

This paper examines the corrosion behavior of the welding heat-affected zone (HAZ) of HDR (high chromium, duplex, corrosion-resistant) duplex stainless steel, which currently faces corrosion-related challenges in marine seawater systems. The corrosion behavior of the HAZ was studied using microstructure analysis, polarization curve experiments, and double-loop potentiodynamic reactivation experiments. The results show that (1) the covering welding current can promote the formation of austenite in the HAZ, and that the covering welding current has no strict correspondence with the formation of austenite; (2) increasing the welding gap properly can facilitate the formation of austenite; (3) increasing the covering welding current enhances the material's pitting resistance, and a covering welding current of 70 A, coupled with a covering welding current of 100 A, represents a reasonable choice in terms of achieving a stronger pitting resistance; (4) in terms of intergranular corrosion resistance, increasing the covering welding current is not conducive to the intergranular corrosion resistance of the material, as the covering current will promote the precipitation of the secondary phase at the grain boundary, thus reducing its intergranular corrosion resistance; and (5) reducing the welding current appropriately contributes to improving the stability of the grain boundary.

20.
ACS Biomater Sci Eng ; 10(5): 2659-2679, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38697939

RESUMO

Connective tissue attaches to bone across an insertion with spatial gradients in components, microstructure, and biomechanics. Due to regional stress concentrations between two mechanically dissimilar materials, the insertion is vulnerable to mechanical damage during joint movements and difficult to repair completely, which remains a significant clinical challenge. Despite interface stress concentrations, the native insertion physiologically functions as the effective load-transfer device between soft tissue and bone. This review summarizes tendon, ligament, and meniscus insertions cross-sectionally, which is novel in this field. Herein, the similarities and differences between the three kinds of insertions in terms of components, microstructure, and biomechanics are compared in great detail. This review begins with describing the basic components existing in the four zones (original soft tissue, uncalcified fibrocartilage, calcified fibrocartilage, and bone) of each kind of insertion, respectively. It then discusses the microstructure constructed from collagen, glycosaminoglycans (GAGs), minerals and others, which provides key support for the biomechanical properties and affects its physiological functions. Finally, the review continues by describing variations in mechanical properties at the millimeter, micrometer, and nanometer scale, which minimize stress concentrations and control stretch at the insertion. In summary, investigating the contrasts between the three has enlightening significance for future directions of repair strategies of insertion diseases and for bioinspired approaches to effective soft-hard interfaces and other tough and robust materials in medicine and engineering.


Assuntos
Tendões , Humanos , Fenômenos Biomecânicos/fisiologia , Tendões/fisiologia , Tendões/anatomia & histologia , Animais , Osso e Ossos/fisiologia , Ligamentos/fisiologia , Fibrocartilagem/fisiologia , Fibrocartilagem/química , Fibrocartilagem/metabolismo , Colágeno/química , Colágeno/metabolismo , Estresse Mecânico
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