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1.
BMC Oral Health ; 24(1): 500, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724912

RESUMO

BACKGROUND: Teeth identification has a pivotal role in the dental curriculum and provides one of the important foundations of clinical practice. Accurately identifying teeth is a vital aspect of dental education and clinical practice, but can be challenging due to the anatomical similarities between categories. In this study, we aim to explore the possibility of using a deep learning model to classify isolated tooth by a set of photographs. METHODS: A collection of 5,100 photographs from 850 isolated human tooth specimens were assembled to serve as the dataset for this study. Each tooth was carefully labeled during the data collection phase through direct observation. We developed a deep learning model that incorporates the state-of-the-art feature extractor and attention mechanism to classify each tooth based on a set of 6 photographs captured from multiple angles. To increase the validity of model evaluation, a voting-based strategy was applied to refine the test set to generate a more reliable label, and the model was evaluated under different types of classification granularities. RESULTS: This deep learning model achieved top-3 accuracies of over 90% in all classification types, with an average AUC of 0.95. The Cohen's Kappa demonstrated good agreement between model prediction and the test set. CONCLUSIONS: This deep learning model can achieve performance comparable to that of human experts and has the potential to become a valuable tool for dental education and various applications in accurately identifying isolated tooth.


Assuntos
Aprendizado Profundo , Dente , Humanos , Dente/anatomia & histologia , Dente/diagnóstico por imagem , Fotografia Dentária/métodos
2.
BMC Vet Res ; 20(1): 191, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734611

RESUMO

BACKGROUND: Many proteins of African swine fever virus (ASFV, such as p72, p54, p30, CD2v, K205R) have been successfully expressed and characterized. However, there are few reports on the DP96R protein of ASFV, which is the virulence protein of ASFV and plays an important role in the process of host infection and invasion of ASFV. RESULTS: Firstly, the prokaryotic expression vector of DP96R gene was constructed, the prokaryotic system was used to induce the expression of DP96R protein, and monoclonal antibody was prepared by immunizing mice. Four monoclonal cells of DP96R protein were obtained by three ELISA screening and two sub-cloning; the titer of ascites antibody was up to 1:500,000, and the monoclonal antibody could specifically recognize DP96R protein. Finally, the subtypes of the four strains of monoclonal antibodies were identified and the minimum epitopes recognized by them were determined. CONCLUSION: Monoclonal antibody against ASFV DP96R protein was successfully prepared and identified, which lays a foundation for further exploration of the structure and function of DP96R protein and ASFV diagnostic technology.


Assuntos
Vírus da Febre Suína Africana , Anticorpos Monoclonais , Epitopos , Camundongos Endogâmicos BALB C , Proteínas Virais , Vírus da Febre Suína Africana/imunologia , Anticorpos Monoclonais/imunologia , Animais , Epitopos/imunologia , Camundongos , Proteínas Virais/imunologia , Anticorpos Antivirais/imunologia , Suínos , Febre Suína Africana/imunologia , Febre Suína Africana/virologia , Feminino
3.
Se Pu ; 42(5): 474-480, 2024 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-38736391

RESUMO

A method was established for the simultaneous detection of 12 prohibited veterinary drugs, including ß2-receptor agonists, nitrofuran metabolites, nitroimidazoles, chlorpromazine, and chloramphenicol, in pig urine. The sample was pretreated by enzymolysis, acid hydrolysis/derivatization, and liquid-liquid extraction combined with solid-phase extraction. Detection was performed using ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Ammonium acetate solution (0.2 mol/L, 4.5 mL) and ß-glucuronidase/aryl sulfatase (40 µL) were added to the sample, which was subsequently enzymolized at 37 ℃ for 2 h. Then, 1.5 mL of 1.0 mol/L hydrochloric acid solution and 100 µL of 0.1 mol/L o-nitrobenzaldehyde solution were added to the sample. The mixture was incubated at 37 ℃ for 16 h, and the analytes were extracted with 8 mL of ethyl acetate by liquid-liquid extraction. The lower aqueous phase obtained after extraction was extracted and purified using a mixed cation-exchange solid-phase extraction column. The extracts were combined, the extraction solution was blow-dried with nitrogen, and the residue was redissolved for determination. The samples were analyzed under multiple-reaction monitoring mode with both positive and negative electrospray ionization, and quantified using an isotope internal standard method. The correlation coefficients (r) of the 12 compounds were >0.99. The limits of detection (LODs) and quantification (LOQs) of chloramphenicol were 0.05 and 0.1 µg/L, respectively, and the LODs and LOQs of the other compounds were 0.25 and 0.5 µg/L, respectively. The mean recoveries and RSDs at 1, 2, and 10 times the LOQ were 83.6%-115.3% and 2.20%-12.34%, respectively. The proposed method has the advantages of high sensitivity, good stability, and accurate quantification; thus, it is suitable for the simultaneous determination of the 12 prohibited veterinary drug residues in pig urine.


Assuntos
Resíduos de Drogas , Espectrometria de Massas em Tandem , Drogas Veterinárias , Animais , Espectrometria de Massas em Tandem/métodos , Suínos , Cromatografia Líquida de Alta Pressão/métodos , Drogas Veterinárias/urina , Drogas Veterinárias/análise , Resíduos de Drogas/análise , Cloranfenicol/urina , Cloranfenicol/análise
4.
Front Immunol ; 15: 1374368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38715616

RESUMO

NOD1 and NOD2 as two representative members of nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family play important roles in antimicrobial immunity. However, transcription mechanism of nod1 and nod2 and their signal circle are less understood in teleost fish. In this study, with the cloning of card9 and ripk2 in Chinese perch, the interaction between NOD1, NOD2, and CARD9 and RIPK2 were revealed through coimmunoprecipitation and immunofluorescence assays. The overexpression of NOD1, NOD2, RIPK2 and CARD9 induced significantly the promoter activity of NF-κB, IFNh and IFNc. Furthermore, it was found that nod1 and nod2 were induced by poly(I:C), type I IFNs, RLR and even NOD1/NOD2 themselves through the ISRE site of their proximal promoters. It is thus indicated that nod1 and nod2 can be classified also as ISGs due to the presence of ISRE in their proximal promoter, and their expression can be mechanistically controlled through PRR pathway as well as through IFN signaling in antiviral immune response.


Assuntos
Proteínas de Peixes , Proteína Adaptadora de Sinalização NOD1 , Proteína Adaptadora de Sinalização NOD2 , Proteína Serina-Treonina Quinase 2 de Interação com Receptor , Transdução de Sinais , Animais , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/genética , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Proteínas de Peixes/imunologia , Percas/genética , Percas/imunologia , Percas/metabolismo , Interferons/metabolismo , Interferons/genética , Regiões Promotoras Genéticas , Transcrição Gênica , Imunidade Inata/genética , Ligação Proteica
5.
Eur J Surg Oncol ; 50(6): 108367, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38718701

RESUMO

BACKGROUND: The effects of the dynamics of serum tumor markers (CA72-4, CEA, CA19-9, CA125 and AFP) before and after neoadjuvant chemotherapy (NACT) on the prognosis of gastric cancer(GC) patients remain unclear. METHODS: The training set contained 334 GC patients from Fujian Medical University Union Hospital (FJMUUH) and 113 GC patients in Qinghai University Affiliated Hospital (QhUAH) were used as an external validation set. Tumor marker regression load (ΔTMRL) indicator, including ΔCA72-4, ΔCEA, ΔCA19-9, ΔCA125, and ΔAFP, is defined as [(postNACT marker- preNACT marker)/preNACT marker]. Tumor marker regression load score (TMRLS) consists of ΔCA72-4, ΔCEA and ΔCA125. The predictive performance of the nomogram-TMRLS was evaluated using the area under the receiver operating characteristic(ROC) curve(AUC), decision curve analysis(DCA), and C-index. RESULTS: Patients from FJMUUH were divided into two groups, TMRLS-low and TMRLS-high, determined by R package maxstat. Survival analysis revealed a higher 3-year overall survival(OS) in the TMRLS-low than in the TMRLS-high group. The TMRLS-high group who received postoperative adjuvant chemotherapy(AC) showed a significantly higher 3-year OS rate than those who did not. Multivariate COX regression analysis indicated that TMRLS was an independent prognostic factor for OS. A nomogram for predicting OS based on TMRLS showed a significantly higher C-index and AUC than the ypTNM stage. The above results were also found in the QhUAH external validation cohort. CONCLUSION: TMRLS is a novel independent prognostic factor for GC who underwent NACT and a radical gastrectomy. Furthermore, the TMRLS-high group, who received postoperative AC, may achieve better survival outcomes. Notably, the predictive performance of the nomogram-TMRLS significantly outperformed that of the ypTNM stage.

6.
Quant Imaging Med Surg ; 14(5): 3731-3743, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38720861

RESUMO

Background: Post-hepatectomy liver failure (PHLF) is still a predominant cause of hepatectomy-related mortality. However, it is difficult to evaluate the remnant liver functional reserve accurately before surgery to prevent PHLF. In this study, we aimed to explore the role of gadoxetate disodium-enhanced magnetic resonance imaging (MRI) in evaluating remnant liver functional reserve. Methods: For this cross-sectional study, the sample retrospectively included 56 patients undergoing liver resections of at least three segments between June 2019 and September 2022 at The General Hospital of the Western Theater Command. Pre-surgery assessments involved liver computer tomography (CT), an indocyanine green (ICG) clearance test, the Child-Pugh scoring system, and liver function serum biochemical indicators. Each patient underwent a gadoxetate disodium-enhanced MRI before the hepatectomy, and we measured the remnant hepatocellular uptake index (rHUI) as well as the standard remnant hepatocellular uptake index (SrHUI). We examined the diagnostic utility of rHUI, SrHUI, indocyanine green retention rate of 15 minutes (ICG R15), and Albumin for PHLF. Receiver operating characteristics (ROC) analyses were used to measure the preoperative liver function parameters (namely, rHUI, SrHUI, ICG R15, and Albumin) for predicting PHLF. The areas under the curve (AUCs) were calculated and compared between different preoperative liver function parameters using the Wilson/Brown method. The Pearson or Spearman correlation coefficient was used for correlation analysis between ICG R15, Albumin, and rHUI and between ICG R15, Albumin, and SrHUI, respectively. Results: Twelve patients (21.43%) had complications of PHLF. We found significant differences in rHUI, SrHUI, ICG R15, and Albumin between the non-PHLF and PHLF groups. The pooled r between ICG R15 and rHUI was -0.591 [95% confidence interval (CI): -0.740 to -0.389, P<0.001], and between ICG R15 and SrHUI was -0.534 (95% CI: -0.703 to -0.308, P<0.001). The area under the curve (AUC) values of rHUI, SrHUI, ICG R15, and Ablumin were 0.871 (sensitivity 81.82%; specificity 91.67%), 0.878 (sensitivity 79.55%; specificity 83.33%), 0.835 (sensitivity 99.73%; specificity 66.67%), and 0.782 (sensitivity 88.64%; specificity 58.33%), respectively. Conclusions: We found that the rHUI and SrHUI calculated using the gadoxetate disodium-enhanced MRI reflected a combination of remnant hepatocyte function and liver volume, and these were useful as a quantitative assessment indicator of remnant liver functional reserve and can be a better predictor of PHLF after major hepatic resection.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38727886

RESUMO

BACKGROUND AND OBJECTIVES: Nirmatrelvir/ritonavir was administered orally to manage mild to moderate symptoms of COVID-19 in adult patients. The objectives of this study were to (i) evaluate the cost-effectiveness of prescribing nirmatrelvir/ritonavir within 5 days of a COVID-19 illness in order to avert hospitalization within a 30-day period in the Malaysia setting; (ii) determine how variations in pricing and hospitalization rates will affect the cost-effectiveness of nirmatrelvir/ritonavir. METHODS: The 30-day hospitalization related to COVID-19 was determined using 1 to 1 propensity score-matched real-world data in Malaysia from 14 July 2022 to 14 November 2022. To determine the total per-person costs related to COVID-19, we added the cost of drug (nirmatrelvir/ritonavir or control), clinic visits and inpatient care. Incremental cost-effectiveness ratio (ICER) per hospitalization averted was calculated. RESULTS: Our cohort included 31,487 patients. The rate of hospitalization within 30 days was found to be 0.35% for the group treated with nirmatrelvir/ritonavir, and 0.52% for the control group. The nirmatrelvir/ritonavir group cost an additional MYR 1,625.72 (USD 358.88) per patient. This treatment also resulted in a reduction of 0.17% risk for hospitalization, which corresponded to an ICER of MYR 946,801.26 (USD 209,006.90) per hospitalization averted. CONCLUSION: In Malaysia, where vaccination rates were high, nirmatrelvir/ritonavir has been shown to be beneficial in the outpatient treatment of adults with COVID-19 who have risk factors; however, it was only marginally cost effective against hospitalization for healthy adults during the Omicron period.

8.
Int J Biol Macromol ; 269(Pt 1): 131808, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38697439

RESUMO

Injectable hydrogels, providing sustained release as implanted materials, have received tremendous attention. In this study, chitosan-based hydrogels were prepared via Schiff base reaction of the aldehyde groups on Poly(NIPAM-co-FBEMA) and the amine groups on chitosan. Owing to the dynamic covalent linkage, the SC/PNF hydrogels exhibit pH-responsive, reversible sol-gel transition, injectable, and self-healing capacity. The mechanical strength of SC/PNF hydrogels can be operated simply by switching the composition or solid content of Poly(NIPAM-co-FBEMA) copolymers. Rheological analyses, including frequency sweeps, strain sweep scanning, and dynamic time sweeps, were employed to demonstrate the relationship between storage modulus (G'), loss modulus (G″), and composition of the SC/PNF hydrogels. In vitro release behaviors reveal that vancomycin-loaded SC/PNF hydrogel could contribute to both the initial burst release (over 1000 ppm within 4 h) and the sustained release (3000 ppm for at least 30 days). Pristine SC/PNF hydrogel holds good biocompatibility toward L929 cells and S. aureus that it degrades as incubated with S. aureus. However, vancomycin-wrapped SC/PNF hydrogel possesses a rapid bacterial-killing effect with a clear inhibition zone. In short, the SC/PNF hydrogels deliver not only sustainable release ability but also tunable physical properties, which are expected to be an outstanding candidate for non-invasive, anti-infection applications.

9.
Bioact Mater ; 38: 95-108, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38699241

RESUMO

Androgenetic alopecia (AGA), the most prevalent clinical hair loss, lacks safe and effective treatments due to downregulated angiogenic genes and insufficient vascularization in the perifollicular microenvironment of the bald scalp in AGA patients. In this study, a hyaluronic acid (HA) based hydrogel-formed microneedle (MN) was designed, referred to as V-R-MNs, which was simultaneously loaded with vascular endothelial growth factor (VEGF) and the novel hair loss drug Ritlecitinib, the latter is encapsulated in slowly biodegradable polyhydroxyalkanoates (PHAs) nanoparticles (R-PHA NPs) for minimally invasive AGA treatment. The integration of HA based hydrogel alongside PHA nanoparticles significantly bolstered the mechanical characteristics of microneedles and enhanced skin penetration efficiency. Due to the biosafety, mechanical strength, and controlled degradation properties of HA hydrogel formed microneedles, V-R-MNs can effectively penetrate the skin's stratum corneum, facilitating the direct delivery of VEGF and Ritlecitinib in a minimally invasive, painless and long-term sustained release manner. V-R-MNs not only promoted angiogenesis and improve the immune microenvironment around the hair follicle to promote the proliferation and development of hair follicle cells, but also the application of MNs to the skin to produce certain mechanical stimulation could also promote angiogenesis. In comparison to the clinical drug minoxidil for AGA treatment, the hair regeneration effect of V-R-MN in AGA model mice is characterized by a rapid onset of the anagen phase, improved hair quality, and greater coverage. This introduces a new, clinically safer, and more efficient strategy for AGA treatment, and serving as a reference for the treatment of other related diseases.

10.
Anal Chim Acta ; 1306: 342612, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692793

RESUMO

Despite the widespread utilization of variable valence metals in electrochemistry, it is still a formidable challenge to enhance the valence conversion efficiency to achieve excellent catalytic activity without introducing heterophase elements. Herein, the in-situ precipitation of Co particles on Co2VO4 not only enhanced the concentration of oxygen vacancies (Ov) but also generated a greater number of low-valence metals, thereby enabling efficient reduction towards Hg(II). The electroanalysis results demonstrate that the sensitivity of Co/Co2VO4 towards Hg(II) was measured at an impressive value of 1987.74 µA µM-1 cm-2, significantly surpassing previously reported results. Further research reveals that Ov acted as the main adsorption site to capture Hg(II). The redox reactions of Co2+/Co3+ and V3+/V4+ played a synergistic role in the reduction of Hg(II), accompanied by the continuous supply of electrons from zero-valent Co to expedite the valence cycle. The Co/Co2VO4/GCE presented remarkable selectivity towards Hg(II), with excellent stability, reproducibility, and anti-interference capability. The electrode also exhibited minimal sensitivity fluctuations towards Hg(II) in real water samples, underscoring its practicality for environmental applications. This study elucidates the mechanism underlying the surface redox reaction of metal oxides facilitated by zero-valent metals, providing us with new strategies for further design of efficient and practical sensors.

11.
Small ; : e2400985, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693073

RESUMO

Ionic liquids have been widely used to improve the efficiency and stability of perovskite solar cells (PSCs), and are generally believed to passivate defects on the grain boundaries of perovskites. However, few studies have focused on the relevant effects of ionic liquids on intragrain defects in perovskites which have been shown to be critical for the performance of PSCs. In this work, the effect of ionic liquid 1-hexyl-3-methylimidazolium iodide (HMII) on intragrain defects of formamidinium lead iodide (FAPbI3) perovskite is investigated. Abundant {111}c intragrain planar defects in pure FAPbI3 grains are found to be significantly reduced by the addition of the ionic liquid HMII, shown by using ultra-low-dose selected area electron diffraction. As a result, longer charge carrier lifetimes, higher photoluminescence quantum yield, better charge carrier transport properties, lower Urbach energy, and current-voltage hysteresis are achieved, and the champion power conversion efficiency of 24.09% is demonstrated. These observations suggest that ionic liquids significantly improve device performance resulting from the elimination of {111}c intragrain planar defects.

12.
World J Gastrointest Surg ; 16(4): 1195-1202, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690044

RESUMO

BACKGROUND: Percutaneous transhepatic stent placement has become a common strategy for the postoperative treatment of portal vein (PV)/superior mesenteric veins (SMV) stenosis/occlusion. It has been widely used after liver transplantation surgery; however, reports on stent placement for acute PV/SMV stenosis after pancreatic surgery within postoperative 3 d are rare. CASE SUMMARY: Herein, we reported a case of intestinal edema and SMV stenosis 2 d after pancreatic surgery. The patient was successfully treated using stent grafts. Although the stenosis resolved after stent placement, complications, including bleeding, pancreatic fistula, bile leakage, and infection, made the treatment highly challenging. The use of anticoagulants was adjusted multiple times to prevent venous thromboembolism and the risk of bleeding. After careful treatment, the patient stabilized, and stent placement effectively managed postoperative PV/SMV stenosis. CONCLUSION: Stent placement is effective and feasible for treating acute PV/SMV stenosis after pancreatic surgery even within postoperative 3 d.

13.
Org Lett ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739778

RESUMO

A three-component reaction for the synthesis of dihydropyrrolo[3,4-e][1,3]thiazines has been developed. Elemental sulfur, maleimides, and 1,3,5-triazinanes are assembled together through sulfuration/nucleophilic attack in N-methylpyrrolidin-2-one (NMP) under mild conditions. A small amount of NaHCO3 is important for the activation of the reaction. In this method, sulfur plays a dual role in thiazine ring formation, while triazinanes are utilized as three-atom synthons in the annulation reaction.

14.
J Org Chem ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738957

RESUMO

A visible-light-enabled photoredox radical cascade cyclization of 2-vinyl benzimidazole derivatives is developed. This chemistry is applicable to a wide range of N-aroyl 2-vinyl benzimidazoles as acceptors, and halo compounds, including alkyl halides, acyl chlorides and sulfonyl chlorides, as radical precursors. The Langlois reagent also serves as an effective partner in this photocatalytic oxidative cascade process. This protocol provides a robust alternative for rendering highly functionalized benzo[4,5]imidazo[1,2-b]isoquinolin-11(6H)-ones.

15.
CNS Neurosci Ther ; 30(4): e14696, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38668740

RESUMO

AIMS: Excessive neuroinflammation mediated mainly by microglia plays a crucial role in ischemic stroke. AZD1390, an ataxia telangiectasia mutated (ATM) specific inhibitor, has been shown to promote radio-sensitization and survival in central nervous system malignancies, while the role of AZD1390 in ischemic stroke remains unknown. METHODS: Real-time PCR, western blot, immunofluorescence staining, flow cytometry and enzyme-linked immunosorbent assays were used to assess the activation of microglia and the release of inflammatory cytokines. Behavioral tests were performed to measure neurological deficits. 2,3,5-Triphenyltetrazolium chloride staining was conducted to assess the infarct volume. The activation of NF-κB signaling pathway was explored through immunofluorescence staining, western blot, co-immunoprecipitation and proximity ligation assay. RESULTS: The level of pro-inflammation cytokines and activation of NF-κB signaling pathway was suppressed by AZD1390 in vitro and in vivo. The behavior deficits and infarct size were partially restored with AZD1390 treatment in experimental stroke. AZD1390 restrict ubiquitylation and sumoylation of the essential regulatory subunit of NF-κB (NEMO) in an ATM-dependent and ATM-independent way respectively, which reduced the activation of the NF-κB pathway. CONCLUSION: AZD1390 suppressed NF-κB signaling pathway to alleviate ischemic brain injury in experimental stroke, and attenuated microglia activation and neuroinflammation, which indicated that AZD1390 might be an attractive agent for the treatment of ischemic stroke.


Assuntos
Microglia , Doenças Neuroinflamatórias , Piridinas , Quinolonas , Animais , Microglia/efeitos dos fármacos , Microglia/metabolismo , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Citocinas/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
Ecotoxicol Environ Saf ; 276: 116277, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604061

RESUMO

Ochratoxin A (OTA) is a common fungal toxin frequently detected in food and human plasma samples. Currently, the physiologically based toxicokinetic (PBTK) model plays an active role in dose translation and can improve and enhance the risk assessment of toxins. In this study, the PBTK model of OTA in rats and humans was established based on knowledge of OTA-specific absorption, distribution, metabolism, and excretion (ADME) in order to better explain the disposition of OTA in humans and the discrepancies with other species. The models were calibrated and optimized using the available kinetic and toxicokinetic (TK) data, and independent test datasets were used for model evaluation. Subsequently, sensitivity analyses and population simulations were performed to characterize the extent to which variations in physiological and specific chemical parameters affected the model output. Finally, the constructed models were used for dose extrapolation of OTA, including the rat-to-human dose adjustment factor (DAF) and the human exposure conversion factor (ECF). The results showed that the unbound fraction (Fup) of OTA in plasma of rat and human was 0.02-0.04% and 0.13-4.21%, respectively. In vitro experiments, the maximum enzyme velocity (Vmax) and Michaelis-Menten constant (Km) of OTA in rat and human liver microsomes were 3.86 and 78.17 µg/g min-1, 0.46 and 4.108 µg/mL, respectively. The predicted results of the model were in good agreement with the observed data, and the models in rats and humans were verified. The PBTK model derived a DAF of 0.1081 between rats and humans, whereas the ECF was 2.03. The established PBTK model can be used to estimate short- or long-term OTA exposure levels in rats and humans, with the capacity for dose translation of OTA to provide the underlying data for risk assessment of OTA.


Assuntos
Modelos Biológicos , Ocratoxinas , Toxicocinética , Ocratoxinas/toxicidade , Ocratoxinas/farmacocinética , Animais , Ratos , Humanos , Medição de Risco , Masculino
17.
Cell Death Differ ; 31(5): 558-573, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570607

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a deadly malignancy with notable metabolic reprogramming, yet the pivotal metabolic feature driving ESCC progression remains elusive. Here, we show that methionine cycle exhibits robust activation in ESCC and is reversely associated with patient survival. ESCC cells readily harness exogenous methionine to generate S-adenosyl-methionine (SAM), thus promoting cell proliferation. Mechanistically, methionine augments METTL3-mediated RNA m6A methylation through SAM and revises gene expression. Integrative omics analysis highlights the potent influence of methionine/SAM on NR4A2 expression in a tumor-specific manner, mediated by the IGF2BP2-dependent stabilization of methylated NR4A2 mRNA. We demonstrate that NR4A2 facilitates ESCC growth and negatively impacts patient survival. We further identify celecoxib as an effective inhibitor of NR4A2, offering promise as a new anti-ESCC agent. In summary, our findings underscore the active methionine cycle as a critical metabolic characteristic in ESCC, and pinpoint NR4A2 as a novel methionine-responsive oncogene, thereby presenting a compelling target potentially superior to methionine restriction.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Metionina , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , Humanos , Metionina/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Linhagem Celular Tumoral , Animais , Oncogenes , Camundongos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Camundongos Nus
18.
Front Bioeng Biotechnol ; 12: 1363742, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558788

RESUMO

In recent years, stem cells and their secretomes, notably exosomes, have received considerable attention in biomedical applications. Exosomes are cellular secretomes used for intercellular communication. They perform the function of intercellular messengers by facilitating the transport of proteins, lipids, nucleic acids, and therapeutic substances. Their biocompatibility, minimal immunogenicity, targetability, stability, and engineerable characteristics have additionally led to their application as drug delivery vehicles. The therapeutic efficacy of exosomes can be improved through surface modification employing functional molecules, including aptamers, antibodies, and peptides. Given their potential as targeted delivery vehicles to enhance the efficiency of treatment while minimizing adverse effects, exosomes exhibit considerable promise. Stem cells are considered advantageous sources of exosomes due to their distinctive characteristics, including regenerative and self-renewal capabilities, which make them well-suited for transplantation into injured tissues, hence promoting tissue regeneration. However, there are notable obstacles that need to be addressed, including immune rejection and ethical problems. Exosomes produced from stem cells have been thoroughly studied as a cell-free strategy that avoids many of the difficulties involved with cell-based therapy for tissue regeneration and cancer treatment. This review provides an in-depth summary and analysis of the existing knowledge regarding exosomes, including their engineering and cardiovascular disease (CVD) treatment applications.

19.
Medicine (Baltimore) ; 103(17): e37949, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669359

RESUMO

Liver fibrosis is a critical factor in the advancement of nonalcoholic fatty liver disease towards cirrhosis. There is limited research exploring the association between obstructive sleep apnea (OSA) and liver fibrosis among community populations. The present study aimed to assess the association between sleep apnea (SA) and liver fibrosis based on the National Health and Nutrition Examination Survey (NHANES). Data were acquired from NHANES survey cycle 2017 to 2020. We assessed liver fibrosis by the median values of liver stiffness measurement (LSM). The diagnosis of SA was based on participants' response to sleep questionnaire. Univariate and multivariate logistic regression were used to validate the association of SA and liver fibrosis. A total of 7615 participants were included in this study. The LSM level of SA group was significantly higher than non-SA group. The proportion of liver fibrosis in SA group was markedly higher than that in non-SA group (14.0% vs 7.3%, P < .001). Univariate logistic analysis showed that SA was positively associated with liver fibrosis (OR = 2.068, 95%CI = 1.715-2.494, P < .001). Further multivariate logistic analysis revealed that SA was independently associated with increased risk of liver fibrosis after adjusting for confounding factors (OR = 1.277, 95%CI = 1.003-1.625, P = .048). The current study demonstrated an independent association between self-reported SA and increased risk of ultrasound-defined liver fibrosis in community-based sample.


Assuntos
Cirrose Hepática , Inquéritos Nutricionais , Ultrassonografia , Humanos , Masculino , Feminino , Cirrose Hepática/epidemiologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/complicações , Pessoa de Meia-Idade , Adulto , Síndromes da Apneia do Sono/epidemiologia , Fatores de Risco , Estudos Transversais , Idoso , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/complicações
20.
Orthop Surg ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658320

RESUMO

OBJECTIVE: Bone marrow mesenchymal stem cells (BMSCs) show significant potential for osteogenic differentiation. However, the underlying mechanisms of osteogenic capability in osteoporosis-derived BMSCs (OP-BMSCs) remain unclear. This study aims to explore the impact of YTHDF3 (YTH N6-methyladenosine RNA binding protein 3) on the osteogenic traits of OP-BMSCs and identify potential therapeutic targets to boost their bone formation ability. METHODS: We examined microarray datasets (GSE35956 and GSE35958) from the Gene Expression Omnibus (GEO) to identify potential m6A regulators in osteoporosis (OP). Employing differential, protein interaction, and machine learning analyses, we pinpointed critical hub genes linked to OP. We further probed the relationship between these genes and OP using single-cell analysis, immune infiltration assessment, and Mendelian randomization. Our in vivo and in vitro experiments validated the expression and functionality of the key hub gene. RESULTS: Differential analysis revealed seven key hub genes related to OP, with YTHDF3 as a central player, supported by protein interaction analysis and machine learning methodologies. Subsequent single-cell, immune infiltration, and Mendelian randomization studies consistently validated YTHDF3's significant link to osteoporosis. YTHDF3 levels are significantly reduced in femoral head tissue from postmenopausal osteoporosis (PMOP) patients and femoral bone tissue from PMOP mice. Additionally, silencing YTHDF3 in OP-BMSCs substantially impedes their proliferation and differentiation. CONCLUSION: YTHDF3 may be implicated in the pathogenesis of OP by regulating the proliferation and osteogenic differentiation of OP-BMSCs.

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