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1.
Food Chem Toxicol ; : 114715, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38729342

RESUMO

As a commonly used food preservative, glycerol monocaprylate (GMC) has limited information and lacked a comprehensive risk assessment. In this study, we conducted in vitro genotoxicity tests, a 90-day subchronic toxicity study, and dietary exposure assessment in China. Rats (n=10/sex/group) were orally administered GMC at doses of 1.02, 2.04, and 4.08 g/kg BW/day along with a water and corn oil for 90 days, including satellite groups (n =5/sex/group) in the control groups and 4.08 g/kg BW dose group for observation after 90 days. Body weight, food consumption, hematology, serum biochemistry, urinalysis, endocrine hormone level and other metrics were examined. GMC did not exhibit genotoxicity based on the genotoxicity tests results, and an acceptable daily intake (ADI) of 40.8 mg/kg BW/day was established based on the 90-day subchronic toxicity study. Estimated daily intake of GMC for general population and consumer population in China were 0.99 mg/kg BW/day and 3.19 mg/kg BW/day respectively, which were significantly lower than the ADI. Our findings suggest that GMC does not pose a known health risk to Chinese consumers at the current usage level.

2.
J Nat Med ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704807

RESUMO

Hepatocellular carcinoma (HCC) is a malignant tumor with extremely high mortality. The tumor microenvironment is the "soil" of its occurrence and development, and the inflammatory microenvironment is an important part of the "soil". Bile acid is closely related to the occurrence of HCC. Bile acid metabolism disorder is not only directly involved in the occurrence and development of HCC but also affects the inflammatory microenvironment of HCC. Yinchenhao decoction, a traditional Chinese medicine formula, can regulate bile acid metabolism and may affect the inflammatory microenvironment of HCC. To determine the effect of Yinchenhao decoction on bile acid metabolism in mice with HCC and to explore the possible mechanism by which Yinchenhao decoction improves the inflammatory microenvironment of HCC by regulating bile acid metabolism, we established mice model of orthotopic transplantation of hepatocellular carcinoma. These mice were treated with three doses of Yinchenhao decoction, then liver samples were collected and tested. Yinchenhao decoction can regulate the disorder of bile acid metabolism in liver cancer mice. Besides, it can improve inflammatory reactions, reduce hepatocyte degeneration and necrosis, and even reduce liver weight and the liver index. Taurochenodeoxycholic acid, hyodeoxycholic acid, and taurohyodeoxycholic acid are important molecules in the regulation of the liver inflammatory microenvironment, laying a foundation for the regulation of the liver tumor inflammatory microenvironment based on bile acids. Yinchenhao decoction may improve the inflammatory microenvironment of mice with HCC by ameliorating hepatic bile acid metabolism.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38700666

RESUMO

OBJECTIVE: This study aimed to compare the prognostic value of rectal cancer by comparing different lymph node staging systems, and a nomogram was constructed based on superior lymph node staging. METHODS: Overall, 8700 patients with rectal cancer was obtained from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015. The area under the curve (AUC), the C index, and the Akaike informativeness criteria (AIC) were used to examine the predict ability of various lymph node staging methods. Prognostic indicators were assessed using univariate and multivariate COX regression, and further correlation nomograms were created after the data were randomly split into training and validation cohorts. To evaluate the effectiveness of the model, the C index, calibration curves, decision curves (DCA), and receiver operating characteristic curve (ROC) were used. We ran Kaplan-Meier survival analyses to look for variations in risk classification. RESULTS: While compared to the N-stage positive lymph node ratio (LNR), the log odds ratio of positive lymph nodes (LODDS) had the highest predictive effectiveness. Multifactorial COX regression analyses were used to create nomograms for overall survival (OS) and cancer-specific survival (CSS). The C indices of OS and CSS for this model were considerably higher than those for TNM staging in the training cohort. The created nomograms demonstrated good efficacy based on ROC, rectification, and decision curves. Kaplan-Meier survival analysis revealed notable variations in patient survival across various patient strata. CONCLUSIONS: Compared to AJCC staging, the LODDS-based nomograms have a more accurate predictive effectiveness in predicting OS and CSS in patients with rectal cancer.

4.
J Appl Stat ; 51(6): 1041-1056, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628452

RESUMO

Traffic pattern identification and accident evaluation are essential for improving traffic planning, road safety, and traffic management. In this paper, we establish classification and regression models to characterize the relationship between traffic flows and different time points and identify different patterns of traffic flows by a negative binomial model with smoothing splines. It provides mean response curves and Bayesian credible bands for traffic flows, a single index, and the log-likelihood difference, for traffic flow pattern recognition. We further propose an impact measure for evaluating the influence of accidents on traffic flows based on the fitted negative binomial model. The proposed method has been successfully applied to real-world traffic flows, and it can be used for improving traffic management.

5.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167202, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38670440

RESUMO

BACKGROUND & AIMS: Hypertrophic scar (HS) is a skin fibroproliferative disorder occurring after burns, surgeries or traumatic injuries, and it has caused a tremendous economic and medical burden. Its molecular mechanism is associated with the abnormal proliferation and transition of fibroblasts and excessive deposition of extracellular matrix. Cartilage intermediate layer protein 2 (CILP2), highly homologous to cartilage intermediate layer protein 1 (CILP1), is mainly secreted predominantly from chondrocytes in the middle/deeper layers of articular cartilage. Recent reports indicate that CILP2 is involved in the development of fibrotic diseases. We investigated the role of CILP2 in the progression of HS. METHODS AND RESULTS: It was found in this study that CILP2 expression was significantly higher in HS than in normal skin, especially in myofibroblasts. In a clinical cohort, we discovered that CILP2 was more abundant in the serum of patients with HS, especially in the early stage of HS. In vitro studies indicated that knockdown of CILP2 suppressed proliferation, migration, myofibroblast activation and collagen synthesis of hypertrophic scar fibroblasts (HSFs). Further, we revealed that CILP2 interacts with ATP citrate lyase (ACLY), in which CILP2 stabilizes the expression of ACLY by reducing the ubiquitination of ACLY, therefore prompting Snail acetylation and avoiding reduced expression of Snail. In vivo studies indicated that knockdown of CILP2 or ACLY inhibitor, SB-204990, significantly alleviated HS formation. CONCLUSION: CILP2 exerts a vital role in hypertrophic scar formation and might be a detectable biomarker reflecting the progression of hypertrophic scar and a therapeutic target for hypertrophic scar.

6.
Phys Med Biol ; 69(9)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38537294

RESUMO

Objective. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a sensitive tool for assessing breast cancer by analyzing tumor blood flow, but it requires gadolinium-based contrast agents, which carry risks such as brain retention and astrocyte migration. Contrast-free MRI is thus preferable for patients with renal impairment or who are pregnant. This study aimed to investigate the feasibility of generating contrast-enhanced MR images from precontrast images and to evaluate the potential use of synthetic images in diagnosing breast cancer.Approach. This retrospective study included 322 women with invasive breast cancer who underwent preoperative DCE-MRI. A generative adversarial network (GAN) based postcontrast image synthesis (GANPIS) model with perceptual loss was proposed to generate contrast-enhanced MR images from precontrast images. The quality of the synthesized images was evaluated using the peak signal-to-noise ratio (PSNR) and structural similarity (SSIM). The diagnostic performance of the generated images was assessed using a convolutional neural network to predict Ki-67, luminal A and histological grade with the area under the receiver operating characteristic curve (AUC). The patients were divided into training (n= 200), validation (n= 60), and testing sets (n= 62).Main results. Quantitative analysis revealed strong agreement between the generated and real postcontrast images in the test set, with PSNR and SSIM values of 36.210 ± 2.670 and 0.988 ± 0.006, respectively. The generated postcontrast images achieved AUCs of 0.918 ± 0.018, 0.842 ± 0.028 and 0.815 ± 0.019 for predicting the Ki-67 expression level, histological grade, and luminal A subtype, respectively. These results showed a significant improvement compared to the use of precontrast images alone, which achieved AUCs of 0.764 ± 0.031, 0.741 ± 0.035, and 0.797 ± 0.021, respectively.Significance. This study proposed a GAN-based MR image synthesis method for breast cancer that aims to generate postcontrast images from precontrast images, allowing the use of contrast-free images to simulate kinetic features for improved diagnosis.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Estudos Retrospectivos , Antígeno Ki-67 , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/química
7.
Opt Express ; 32(4): 4887-4901, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439229

RESUMO

In underwater wireless optical communication, orbital angular momentum (OAM) states suffer from turbulence distortions. This study aims to investigate the effectiveness of auto-focusing and OAM entanglement of the beams in reducing the turbulence effects. We implement the single-phase approximation and the extended Huygens-Fresnel principle to derive the detection probability of the entangled Airy beams under unstable oceanic turbulence. The results show that auto-focusing can protect the signal OAM mode and suppress modal crosstalks, while entangled OAM states can further enhance the resistance against oceanic turbulence around the focus position. The numerical analysis demonstrates that after the auto-focusing position, the beams evolve in completely opposite directions, indicating that the focal length should be modulated according to the length of a practical link to enhance received signals. These findings suggest that entangled auto-focusing vortex beams may be a desirable light source in underwater communication systems.

8.
J Med Chem ; 67(6): 4889-4903, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38485922

RESUMO

Directly blocking the Keap1-Nrf2 pathway is a promising strategy for the mitigation of acute lung injury (ALI). Peptide Keap1-Nrf2 inhibitors have been reported to have a high Keap1 binding affinity. However, these inhibitors showed weak activity in cells and/or animals. In this study, we designed a series of linear peptides from an Nrf2-based 9-mer Ac-LDEETGEFL-NH2. To improve the cellular activity, we further designed cyclic peptides based on the crystal complex of Keap1 with a linear peptide. Among them, cyclic 9-mer ZC9 targeting Keap1 showed a better affinity (KD2 = 51 nM). Specifically, it exhibited an acceptable water solubility (>38 mg/mL), better cell permeability, cell activity, and metabolic stability (serum t1/2 > 24 h). In the in vitro LPS-induced oxidative damages and ALI model, ZC9 showed significant dose-response reversal activity without apparent toxicity. In conclusion, our results suggested ZC9 as a lead cyclic peptide targeting the Keap1-Nrf2 pathway for ALI clinical treatment.


Assuntos
Lesão Pulmonar Aguda , Peptídeos Cíclicos , Animais , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Peptídeos Cíclicos/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Peptídeos/química , Lesão Pulmonar Aguda/tratamento farmacológico
9.
J Chem Theory Comput ; 20(6): 2570-2581, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38470415

RESUMO

The determination of the solvation free energy of ions and molecules holds profound importance across a spectrum of applications spanning chemistry, biology, energy storage, and the environment. Molecular dynamics simulations are powerful tools for computing this critical parameter. Nevertheless, the accurate and efficient calculation of the solvation free energy becomes a formidable endeavor when dealing with complex systems characterized by potent Coulombic interactions and sluggish ion dynamics and, consequently, slow transition across various metastable states. In the present study, we expose limitations stemming from the conventional calculation of the statistical inefficiency g in the thermodynamic integration method, a factor that can hinder the determination of convergence of the solvation free energy and its associated uncertainty. Instead, we propose a robust scheme based on Gelman-Rubin convergence diagnostics. We leverage this improved estimation of uncertainties to introduce an innovative accelerated thermodynamic integration method based on the Gaussian Process regression. This methodology is applied to the calculation of the solvation free energy of trivalent rare-earth elements immersed in ionic liquids, a scenario in which the aforementioned challenges render standard approaches ineffective. The proposed method proves to be effective in computing solvation free energy in situations where traditional thermodynamic integration methods fall short.

10.
Medicine (Baltimore) ; 103(12): e37403, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518052

RESUMO

RATIONALE: Giant intracranial aneurysms pose a significant threat due to high mortality rates upon rupture, prompting interventions such as neurosurgical clipping or endovascular coiling. PATIENT CONCERNS: We present a rare case involving a 47-year-old female with a history of successfully treated ruptured giant intracranial aneurysms. Six months post-surgical clipping, she developed symptoms of acute ischemic stroke, prompting the decision for neurosurgical coiling and stent-assisted aneurysm coil embolization due to recurrent intracranial aneurysms. DIAGNOSES: Subsequently, occlusion occurred at the previously implanted stent site during embolization, necessitating exploration of alternative therapeutic options. Digital subtraction angiography confirmed stent occlusion in the right middle cerebral artery. INTERVENTIONS: Despite an initial unsuccessful attempt using a direct aspiration first-pass technique, the patient underwent successful mechanical thrombectomy with a retrievable stent, leading to successful reperfusion. This study aims to highlight the challenges and therapeutic strategies in managing delayed cerebral vascular occlusion following stent-assisted coil embolization, emphasizing the significance of exploring alternative interventions to enhance patient outcomes. OUTCOMES: The patient achieved successful reperfusion, and the study underscores the importance of recognizing and addressing delayed cerebral vascular occlusion after stent-assisted coil embolization for recurrent cerebral aneurysms. LESSONS: Our findings suggest that retrievable stent mechanical thrombectomy may serve as a viable therapeutic option in challenging scenarios, emphasizing the need for further exploration of alternative interventions to enhance patient care.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Aneurisma Intracraniano , AVC Isquêmico , Tromboembolia , Feminino , Humanos , Pessoa de Meia-Idade , Aneurisma Roto/cirurgia , Angiografia Cerebral , Embolização Terapêutica/métodos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , AVC Isquêmico/complicações , Estudos Retrospectivos , Stents , Trombectomia , Tromboembolia/complicações , Resultado do Tratamento
11.
Bull Entomol Res ; 114(2): 230-236, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38475984

RESUMO

As an environmental factor, temperature impacts the distribution of species and influences interspecific competition. The molecular chaperones encoded by small heat shock proteins (sHsps) are essential for rapid, appropriate responses to environmental stress. This study focuses on Hsp20.8, which encodes a temperature-responsive sHsp in Liriomyza trifolii, an insect pest that infests both agricultural and ornamental crops. Hsp20.8 expression was highest at 39℃ in L. trifolii pupae and adults, and expression levels were greater in pupae than in adults. Recombinant Hsp20.8 was expressed in Escherichia coli and conferred a higher survival rate than the empty vector to bacterial cells exposed to heat stress. RNA interference experiments were conducted using L. trifolii adults and prepupae and the knockdown of Hsp20.8 expression increased mortality in L. trifolii during heat stress. The results expand our understanding of sHsp function in Liriomyza spp. and the ongoing adaptation of this pest to climate change. In addition, this study is also important for predicting the distribution of invasive species and proposing new prevention and control strategies based on temperature adaptation.


Assuntos
Dípteros , Proteínas de Insetos , Animais , Dípteros/genética , Dípteros/fisiologia , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Temperatura Alta , Termotolerância , Pupa/crescimento & desenvolvimento , Pupa/genética , Pupa/metabolismo , Proteínas de Choque Térmico Pequenas/metabolismo , Proteínas de Choque Térmico Pequenas/genética , Interferência de RNA
12.
Burns Trauma ; 12: tkad057, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38328438

RESUMO

Background: Tissue expansion, a technique in which skin regeneration is induced by mechanical stretch stimuli, is commonly used for tissue repair and reconstruction. In this study, we aimed to monitor the autophagy levels of expanded skin after the application of expansion stimuli and explore the effect of autophagy modulation on skin regeneration. Methods: A rat scalp expansion model was established to provide a stable expanded skin response to mechanical stretch. Autophagy levels at different time points (6, 12, 24, 48 and 72 h after the last expansion) were detected via western blotting. The effect of autophagy regulation on skin regeneration during tissue expansion was evaluated via skin expansion efficiency assessment, western blotting, immunofluorescence staining, TUNEL staining and laser Doppler blood flow imaging. Results: The autophagic flux reached its highest level 48 h after tissue expansion. Activating autophagy by rapamycin increased the area of expanded skin as well as the thicknesses of epidermis and dermis. Furthermore, activating autophagy accelerated skin regeneration during tissue expansion by enhancing the proliferation of cells and the number of epidermal basal and hair follicle stem cells, reducing apoptosis, improving angiogenesis, and promoting collagen synthesis and growth factor secretion. Conversely, the regenerative effects were reversed when autophagy was blocked. Conclusions: Autophagy modulation may be a promising therapeutic strategy for improving the efficiency of tissue expansion and preventing the incidence of the complication of skin necrosis.

13.
J Plast Reconstr Aesthet Surg ; 91: 119-127, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412602

RESUMO

Haematoma is an early complication of tissue expander placement and can lead to infection, capsule contracture and various complications, hindering successful reconstruction. However, no scientific models can accurately predict the risk of haematoma following tissue expansion. Therefore, this study aimed to develop and validate a prediction model for haematoma following tissue expander placement. The medical records of patients who underwent expander placement between 2001 and 2021 were obtained from the clinical database of the Department of Plastic Surgery at the Xijing Hospital. A total of 4579 consecutive patients with 7080 expanders and 179 expanded pocket haematomas were analysed. Multivariate logistic regression analysis identified adult age (P = 0.006), male sex (P < 0.001), scar reconstruction (P = 0.019), perioperative hypertension (P < 0.001), face and neck location (P = 0.002) and activated partial thromboplastin time above the normal range (P < 0.001) as risk factors for haematoma. Therefore, these were included in the prediction model, and a nomogram was constructed. The discrimination of the nomogram was robust (area under the curve: 0.78; 95% confidence interval: 0.72-0.83). Further, the prediction model had a strong fit (Hosmer-Lemeshow test, P = 0.066) and maintained similar discrimination after considering performance optimism (bootstrapped area under the curve: 0.79; 95% confidence interval: 0.73-0.84). This clinical prediction model was created using a generalisable dataset and can be utilised to obtain valid haematoma predictions after expander placement, assisting surgeons in implementing preventive measures or interventions to reduce the occurrence of haematoma.


Assuntos
Modelos Estatísticos , Dispositivos para Expansão de Tecidos , Adulto , Humanos , Masculino , Dispositivos para Expansão de Tecidos/efeitos adversos , Estudos Retrospectivos , Prognóstico , Expansão de Tecido/efeitos adversos , Hematoma/epidemiologia , Hematoma/etiologia
14.
Regul Toxicol Pharmacol ; 148: 105586, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38382587

RESUMO

The increasing use of titanium dioxide (TiO2) nanoparticles (NPs) has raised concern about the safety of food additive TiO2. TiO2 has been considered no longer safe by EFSA due to concerns over genotoxicity, however, there are conflicting opinions upon the safety of TiO2 as a food additive, and the number of in vivo genotoxicity studies conducted on food additive TiO2 was limited. In order to investigate the potential genotoxicity of food additive TiO2, we evaluated the genotoxicity of a commercial food additive TiO2 (average size of 135.54 ± 41.01 nm, range from 60.83 to 230.16 nm, NPs account for 30% by number) using a battery of standard in vivo tests, including mammalian erythrocyte micronucleus test, mammalian bone marrow chromosomal aberration test and in vivo mammalian alkaline comet test. After 15 days of consecutive intragastric administration at doses of 250, 500, and 1000 mg/kgBW, food additive TiO2 neither increased the frequencies of bone marrow micronuclei or chromosomal aberration in mice, nor induced DNA strand breakage in rat liver cells. These results indicate that under the condition of this study, food additive TiO2 does not have genotoxic potential although it contains a fraction of NPs.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Ratos , Camundongos , Animais , Aditivos Alimentares/toxicidade , Dano ao DNA , Testes para Micronúcleos , Titânio/toxicidade , Aberrações Cromossômicas/induzido quimicamente , Ensaio Cometa , Mamíferos
15.
Anal Methods ; 16(10): 1531-1537, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38391082

RESUMO

Nitrobenzene is currently the most widely used explosive substance, and is known for its high toxicity and mutagenicity. It can cause severe environmental and water pollution, posing a risk to public health. Among various explosives analysis methods, surface-enhanced Raman spectroscopy (SERS) has the advantages of fast analysis speed, low detection cost, and easy operation, and has become one of the most promising analytical detection methods. Here, we present a portable and reliable sol-based SERS method for the detection of trace amounts of 2,4,6-trinitrotoluene (TNT) in different water bodies. The Meisenheimer complex formed by nitrobenzene and hydrazine hydrate can assemble on unmodified Au nanoparticles in a sol via Au-N bonds, enabling rapid detection of TNT in seawater, lake water, and tap water using a portable Raman spectrometer. Experimental results show that this SERS method can complete the detection within a few minutes and the detection sensitivity can reach 0.01 mg L-1, which is far lower than China's national standard of no more than 0.5 mg L-1. Furthermore, this method was also successfully applied to detect trace 2,4-dinitrotoluene (2,4-DNT) and picric acid (2,4,6-trinitrophenol) in water, demonstrating its strong applicability for on-site detection of nitrobenzene explosives.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38311980

RESUMO

In this study, the transcriptome analysis was practiced to identify potential genes of probiotic Bacillus subtilis BSN313 involved in selenium (Se) enrichment metabolism. The transcriptomic variation of the strain was deliberated in presence of three different sodium selenite concentrations (0, 3, and 20 µg/mL). The samples were taken at 1 and 13 h subsequent to inoculation of selenite and gene expression profiles in Se metabolism were analyzed through RNA sequencing. The gene expression levels of the pre log phase were lower than the stationary phase. It is because, the bacteria has maximum grown with high concentration of Se (enriched with organic Se), at stationary phase. Bacterial culture containing 3 µg/mL concentration of inorganic Se (sodium selenite) has shown highest gene expression as compared to no or high concentration of Se. This concentration (3 µg/mL) of sodium selenite (as Se) in the medium promoted the upregulation of thioredoxin reductase expression, whereas its higher Se concentration inhibited the formation of selenomethionine (SeMet). The result of 5 L bioreactor fermentation showed that SeMet was also detected in the fermentation supernatant as the growth entered in the late stationary phase and reached up to 857.3 ng/mL. The overall intracellular SeMet enriched content in BSN313 was extended up to 23.4 µg/g dry cell weight. The other two selenoamino acids (Se-AAs), methyl-selenocysteine, and selenocysteine were hardly detected in medium supernatant. From this study, it was concluded that SeMet was the highest content of organic Se byproduct biosynthesized by B. subtilis BSN313 strain in Se-enriched medium during stationary phase. Thus, B. subtilis BSN313 can be considered a commercial probiotic strain that can be used in the food and pharmaceutical industries. This is because it can meet the commercial demand for Se-AAs (SeMet) in both industries.

18.
Eur Radiol Exp ; 8(1): 4, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38172486

RESUMO

Recent advancements in diagnostic CT detector technology have made it possible to resolve anatomical features smaller than 20 LP/cm, referred to as ultra-high-resolution (UHR) CT. Subtle biological motions that did not affect standard-resolution (SR) CT may not be neglected in UHR. This study aimed to quantify the cardiac-induced motion of the pancreas and simulate its impact on the image quality of UHR-CT. We measured the displacement of the head of the pancreas in three healthy volunteers using Displacement Encoding with Stimulated Echoes (DENSE) MRI. The results were used to simulate SR- and UHR-CT acquisitions affected by pancreatic motion.We found pancreatic displacement in the 0.24-1.59 mm range during one cardiac cycle across the subjects. The greatest displacement was observed in the anterior-posterior direction. The time to peak displacement varied across subjects. Both SR and UHR images showed reduced image quality, as measured by radial modulation transfer function, due to cardiac-induced motion, but the motion artifacts caused more severe degradation in UHR acquisitions. Our investigation of cardiac-induced pancreatic displacement reveals its potential to degrade both standard and UHR-CT scans. To fully utilize the improvement in spatial resolution offered by UHR-CT, the effects of cardiac-induced motion in the abdomen need to be understood and corrected.Relevance statement Advancements in CT detector technology have enhanced CT scanner spatial resolution to approximately 100 µm. Consequently, previously ignored biological motions such as the cardiac-induced motion of the pancreas now demand attention to fully utilize this improved resolution.


Assuntos
Cavidade Abdominal , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Tomógrafos Computadorizados , Movimento (Física) , Pâncreas/diagnóstico por imagem
19.
Dalton Trans ; 53(6): 2797-2806, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38226891

RESUMO

Novel half-sandwich ruthenium complexes termed [(p-cymene)RuClL] were synthesized by chelating arylhydrazone ligands with [(p-cymene)RuCl2]2 and were then fully characterized using different spectroscopic and analytical techniques. The crystal structure of complex 4 indicated that the hydrazone ligands bonded to the ruthenium ion in a bidentate manner through the imine nitrogen and imidazolate oxygen, exhibiting a pseudo-octahedral geometry centered by the ruthenium atom. The as-fabricated air and moisture stable half-sandwich ruthenium complexes demonstrated excellent catalytic activity towards the N-alkylation of hydrazides under mild conditions. Under the catalysis of ruthenium complexes, acyl hydrazides were reacted with different types of alcohols in a one-pot reaction, resulting in N-alkylation hydrazides with different substituents. This catalyst exhibited characteristics such as high catalytic efficiency, broad substrate scope, and mild reaction conditions, indicating that it has great potential for industrial applications.

20.
Bioorg Med Chem Lett ; 99: 129627, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38272189

RESUMO

Metastasis is one of the major causes of death in patients with cancer, and cell invasion plays a fundamental part in this process. Because of the absence of efficacious treatments, caring for these patients is challenging. Recently, we optimized the structure of the naturally occurring lasso peptide sungsanpin. We identified two peptides, octapeptide S3 and cyclic peptide S4, which inhibited invasion into A549 cells effectively. We undertook an alanine scan of S3 to explore the structure-activity relationship. The linear octapeptide S3-4 and cyclic peptide S4-1 exhibited improved inhibition of invasion into A549 cells. We modified S3-4 to obtain S3-4K, which displayed much higher inhibitory activity against invasion into A549 cells than S3-4. Of all peptides tested, S4-1 upregulated significantly mRNA of tissue inhibitor matrix metalloproteinase TIMP-1 and TIMP-2.


Assuntos
Peptídeos , Inibidor Tecidual de Metaloproteinase-1 , Humanos , Inibidor Tecidual de Metaloproteinase-1/genética , Metaloproteinases da Matriz , Células A549 , Peptídeos Cíclicos
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