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1.
Math Biosci Eng ; 18(4): 3680-3689, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-34198406

RESUMO

Objective Traditional breast ultrasound relies too much on the operation skills of diagnostic doctors, and the repeatability in different doctors was low. This study aimed to evaluate the assistant diagnostic value of S-Detect artificial intelligence (AI) system in differentiating benign from malignant breast masses. Methods The ultrasound images of 40 patients who underwent ultrasound examination in our hospital were collected. The conventional ultrasound images, elastic images, and S-Detect mode of breast lesions were analyzed. The breast imaging reporting and data system recommended by the American Society of Radiology (BI-RADS) classification for each breast mass was evaluated both by the doctor and AI. The receiver operator characteristics (ROC) curves were drawn to compare the diagnostic efficiency. Result Among the 40 lesions, 16 were benign, and 24 were malignant. The S-Detect AI system had a high diagnostic efficiency for malignant mass, with sensitivity, specificity, and accuracy of 95.8%, 93.8%, and 89.6%. The accuracy of AI was higher than the elastic image and then than the conventional gray-scale image. With the assistance of the S-Detect AI system, the accuracy of BI-RADS classification was improved significantly. Conclusion The S-Detect AI system will enhance breast cancer diagnostic accuracy and improve ultrasound examination quality.


Assuntos
Neoplasias da Mama , Inteligência Artificial , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Sensibilidade e Especificidade , Ultrassonografia Mamária
3.
Int J Nanomedicine ; 15: 5701-5718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848392

RESUMO

INTRODUCTION: Traditional chemotherapy for ovarian cancer is limited due to drug resistance and systemic side effects. Although various targeted drug delivery strategies have been designed to enhance drug accumulation at the tumor site, simply improvement of targeting capability has not consistently led to satisfactory outcomes. Herein, AMD3100 was selected as the targeting ligand because of its high affinity to chemokine receptor 4 (CXCR4), which was highly expressed on ovarian cancer cells. Moreover, the AMD3100 has been proved having blockage capability of stromal cell-derived factor 1 (SDF-1 or CXCL12)/CXCR4 axis and to be a sensitizer of chemotherapeutic therapy. We designed a dual-functional targeting delivery system by modifying paclitaxel (PTX)-loaded PEGylation bovine serum albumin (BSA) nanoparticles (NPs) with AMD3100 (AMD-NP-PTX), which can not only achieve specific tumor-targeting efficiency but also enhance the therapeutic outcomes. METHODS: AMD3100 was chemically modified to Mal-PEG-NHS followed by reacting with BSA, then AMD-NP-PTX was synthesized and characterized. The targeting efficiency of AMD-NP was evaluated both in vitro and in vivo. The anticancer effect of AMD-NP-PTX was determined on Caov3 cells and ovarian cancer-bearing nude mice. Finally, the potential therapeutic mechanism was studied. RESULTS: AMD-NP-PTX was synthesized successfully and well characterized. Cellular uptake assay and in vivo imaging experiments demonstrated that NPs could be internalized by Caov3 cells more efficiently after modification of AMD3100. Furthermore, the AMD-NP-PTX exhibited significantly enhanced inhibition effect on tumor growth and metastasis compared with PTX, NP-PTX and free AMD3100 plus NP-PTX both in vitro and in vivo, and demonstrated improved safety profile. We also confirmed that AMD-NP-PTX worked through targeting CXCL12/CXCR4 axis, thereby disturbing its downstream signaling pathways including epithelial-mesenchymal transition (EMT) processes and nuclear factor κB (NF-κB) pathway. CONCLUSION: The AMD-NP-PTX we designed would open a new avenue for dual-functional NPs in ovarian cancer therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quimiocina CXCL12/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas Multifuncionais/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Receptores CXCR4/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzilaminas , Células CHO , Linhagem Celular Tumoral , Quimiocina CXCL12/antagonistas & inibidores , Cricetulus , Ciclamos , Feminino , Compostos Heterocíclicos/administração & dosagem , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapia de Alvo Molecular , Nanopartículas Multifuncionais/química , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Soroalbumina Bovina/química , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Nucleic Acids Res ; 48(16): 9181-9194, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32789493

RESUMO

The NAD+-dependent deacetylase and mono-ADP-ribosyl transferase SIRT6 stabilizes the genome by promoting DNA double strand break repair, thereby acting as a tumor suppressor. However, whether SIRT6 regulates nucleotide excision repair (NER) remains unknown. Here, we showed that SIRT6 was recruited to sites of UV-induced DNA damage and stimulated the repair of UV-induced DNA damage. Mechanistic studies further indicated that SIRT6 interacted with DDB2, the major sensor initiating global genome NER (GG-NER), and that the interaction was enhanced upon UV irradiation. SIRT6 deacetylated DDB2 at two lysine residues, K35 and K77, upon UV stress and then promoted DDB2 ubiquitination and segregation from chromatin, thereby facilitating downstream signaling. In addition, we characterized several SIRT6 mutations derived from melanoma patients. These SIRT6 mutants ablated the stimulatory effect of SIRT6 on NER and destabilized the genome due to (i) partial loss of enzymatic activity (P27S or H50Y), (ii) a nonsense mutation (R150*) or (iii) high turnover rates (G134W). Overall, we demonstrate that SIRT6 promotes NER by deacetylating DDB2, thereby preventing the onset of melanomagenesis.


Assuntos
Carcinogênese/genética , Dano ao DNA/genética , Proteínas de Ligação a DNA/genética , Melanoma/genética , Sirtuínas/genética , Carcinogênese/efeitos da radiação , Cromatina/genética , Cromatina/efeitos da radiação , Dano ao DNA/efeitos da radiação , Reparo do DNA/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Células HeLa , Humanos , Melanoma/patologia , Mutação/efeitos da radiação , Ubiquitinação/efeitos da radiação , Raios Ultravioleta/efeitos adversos
5.
J Clin Pharm Ther ; 45(6): 1414-1421, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32737938

RESUMO

WHAT IS KNOWN AND OBJECTIVES: Caffeine citrate is a commonly used methylxanthine for pharmacologic treatment of apnea of prematurity. The aim of this study was to develop and verify a population pharmacokinetic (PPK) model, which can provide a reference for individualized caffeine citrate treatment of apnea in Chinese premature infants. METHODS: A total of 88 serum concentration measurements from 46 preterm patients (median gestational age 29 weeks) were retrospectively collected and the relevant clinical data of patients were recorded. The PPK analysis was performed by non-linear mixed-effect modelling method using NONMEM. Allometric scaling was applied in the PPK analysis, and the final model was evaluated by graphic and statistical methods, including goodness-of-fit plots, normalized prediction distribution errors plots and bootstrap procedures. RESULTS: A one-compartment model with first-order elimination was successfully fitted to the data. The typical scaled values for the parameters clearance and volume of distribution (V) were 0.268 L/h and 109 L per 70 kg, respectively. The weight at the time of blood collection (CW) and post-natal age were identified as important predictors for pharmacokinetic parameters of caffeine. The evaluation process showed good stability and predictability of the final PPK model. WHAT IS NEW AND CONCLUSION: This is a complete PPK study of caffeine citrate in Chinese premature infants with apnea, which complements caffeine pharmacokinetic data of the premature from China. A final PPK model was developed which may serve as a beneficial tool for the use of caffeine citrate in the treatment of apnea in Chinese preterm infants.


Assuntos
Apneia/tratamento farmacológico , Cafeína/farmacocinética , Estimulantes do Sistema Nervoso Central/farmacocinética , Citratos/farmacocinética , Modelos Biológicos , Povo Asiático , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Citratos/administração & dosagem , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/tratamento farmacológico , Masculino , Dinâmica não Linear , Estudos Retrospectivos
6.
Chin J Integr Med ; 24(6): 474-480, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29860581

RESUMO

Multidrug resistance (MDR) is a major cause of cancer chemotherapy failure, and it is important to develop suitable reversal agents to overcome MDR. A majority of chemical reversal agents have acceptable reversal effects. However, the toxicity and adverse reactions associated with these agents restricts their clinical use. Chinese medicines (CMs) have lower toxicities and adverse reactions and are associated with multiple components, multiple targets and reduced toxicity. CMs have several advantages and could reverse MDR, decrease drug dosage, enhance patient compliance and increase efficacy. This review summarizes the current progress of CM reversal agents..


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Pesquisa , Humanos , Extratos Vegetais/farmacologia
7.
Mol Pharm ; 13(8): 2667-76, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27379550

RESUMO

Solid lipid nanoparticles (SLNs) are one of the most promising nanocarriers to increase the oral absorption of drugs with poor solubility and low permeability. However, the absorption mechanism of SLNs remains incomplete and thus requires further careful consideration. In this study, positively charged chitosan (CS) modified SLNs or hydroxypropyl trimethylammonium chloride chitosan (HACC) modified SLNs were designed and their absorption mechanisms were fully clarified to improve the oral absorption of docetaxel (DTX). The HACC-DTX-SLNs showed the highest cellular uptake in Caco-2 cell monolayer; the transport efficacy in the follicle-associated epithelium cell monolayer was higher than that in the Caco-2 cell monolayer. The CS- or HACC-modified SLNs could reversibly regulate the transepithelial electrical resistance and the expressions of tight junction (TJ) associated proteins, such as claudin-1, occludin, and zonula occludens-1. The uptake of HACC-DTX-SLNs through Peyer's patches was higher than that of the normal tissue of the small intestine in rats. The enhanced absorption mechanisms of HACC-DTX-SLNs were mainly related to the caveola-mediated endocytosis, M cell phagocytosis, and reversible TJ opening.


Assuntos
Mucosa Intestinal/metabolismo , Lipídeos/química , Nanopartículas/química , Taxoides/metabolismo , Animais , Células CACO-2 , Quitosana/química , Docetaxel , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Ratos , Ratos Sprague-Dawley
8.
Drug Deliv ; 23(1): 41-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24735247

RESUMO

This study aimed to improve the dissolution rate and oral bioavailability of valsartan (VAL), a poorly soluble drug using solid dispersions (SDs). The SDs were prepared by a freeze-drying technique with polyethylene glycol 6000 (PEG6000) and hydroxypropylmethylcellulose (HPMC 100KV) as hydrophilic polymers, sodium hydroxide (NaOH) as an alkalizer, and poloxamer 188 as a surfactant without using any organic solvents. In vitro dissolution rate and physicochemical properties of the SDs were characterized using the USP paddle method, differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and Fourier transform-infrared (FT-IR) spectroscopy, respectively. In addition, the oral bioavailability of SDs in rats was evaluated by using VAL (pure drug) as a reference. The dissolution rates of the SDs were significantly improved at pH 1.2 and pH 6.8 compared to those of the pure drug. The results from DSC, XRD showed that VAL was molecularly dispersed in the SDs as an amorphous form. The FT-IR results suggested that intermolecular hydrogen bonding had formed between VAL and its carriers. The SDs exhibited significantly higher values of AUC 0-24 h and Cmax in comparison with the pure drug. In conclusion, hydrophilic polymer-based SDs prepared by a freeze-drying technique can be a promising method to enhance dissolution rate and oral bioavailability of VAL.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacocinética , Valsartana/administração & dosagem , Valsartana/farmacocinética , Animais , Disponibilidade Biológica , Portadores de Fármacos/química , Liofilização , Derivados da Hipromelose , Masculino , Poloxâmero , Polietilenoglicóis , Polímeros , Ratos , Ratos Sprague-Dawley , Solubilidade
9.
Can J Clin Pharmacol ; 14(1): e40-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17237524

RESUMO

In order to understand a drug's full profile in the post-marketing environment, information is needed regarding utilization patterns, beneficial effects, ADRs and economic value. China, the most populated country in the world, has the largest number of people who are taking medications. To begin to appreciate the impact of these medications, a multifunctional evaluation and surveillance system was developed, the Shanghai Drug Monitoring and Evaluative System (SDMES). Set up by the Shanghai Center for Adverse Drug Reaction Monitoring in 2001, the SDMES contains three databases: a population health data base of middle aged and elderly persons; hospital patient medical records; and a spontaneous ADR reporting database. Each person has a unique identification and Medicare number, which permits record-linkage within and between these three databases. After more than three years in development, the population health database has comprehensive data for more than 320,000 residents. The hospital database has two years of inpatient medical records from five major hospitals, and will be increasing to 10 hospitals in 2007. The spontaneous reporting ADR database has collected 20,205 cases since 2001 from approximately 295 sources, including hospitals, pharmaceutical companies, drug wholesalers and pharmacies. The SDMES has the potential to become an important national and international pharmacoepidemiology resource for drug evaluation.


Assuntos
Vigilância de Produtos Comercializados , Sistemas de Notificação de Reações Adversas a Medicamentos , China , Bases de Dados como Assunto
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