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1.
Anal Chem ; 95(32): 11934-11942, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37527423

RESUMO

Small extracellular vesicles (sEVs) are increasingly reported to play important roles in numerous physiological and pathological processes. Cellular uptake of sEVs is of great significance for functional regulation in recipient cells. Although various sEV quantification, labeling, and tracking methods have been reported, it is still highly challenging to quantify the absolute amount of cellular uptake of sEVs and correlate this information with phenotypic variations in the recipient cell. Therefore, we developed a novel strategy using lanthanide element labeling and inductively coupled plasma-mass spectrometry (ICP-MS) for the absolute and sensitive quantification of sEVs. This strategy utilizes the chelation interaction between Eu3+ and the phosphate groups on the sEV membrane for specific labeling. sEVs internalized by cells can then be quantified by ICP-MS using a previously established linear relationship between the europium content and the particle numbers. High Eu labeling efficiency and stability were demonstrated by various evaluations, and no structural or functional alterations in the sEVs were discovered after Eu labeling. Application of this method revealed that 4020 ± 171 sEV particles/cell were internalized by HeLa cells at 37 °C and 61% uptake inhibition at 4 °C. Further investigation led to the quantitative differential analysis of sEV cellular uptake under the treatment of several chemical endocytosis inhibitors. A 23% strong inhibition indicated that HeLa cells uptake sEVs mainly through the macropinocytosis pathway. This facile labeling and absolute quantification strategy of sEVs with ppb-level high sensitivity is expected to become a potential tool for studying the functions of sEVs in intracellular communication and cargo transportation.

2.
Molecules ; 28(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37299024

RESUMO

Hericium erinaceus, a mushroom species commonly known as Yamabushitake in Japan, is known to have a stimulatory effect on neurotrophic factors, such as brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). Hericenone C, a meroterpenoid with palmitic acid as the fatty acid side chain, is reported to be one such stimulant. However, according to the structure of the compound, the fatty acid side chain seems highly susceptible to lipase decomposition, under in vivo metabolic conditions. To study this phenomenon, hericenone C from the ethanol extract of the fruiting body was subjected to lipase enzyme treatment and observed for changes in the chemical structure. The compound formed after the lipase enzyme digestion was isolated and identified using LC-QTOF-MS combined with 1H-NMR analysis. It was found to be a derivative of hericenone C without its fatty acid side chain and was named deacylhericenone. Interestingly, a comparative investigation of the neuroprotective properties of hericenone C and deacylhericenone showed that the BDNF mRNA expression in human astrocytoma cells (1321N1) and the protection against H2O2-induced oxidative stress was considerably higher in the case of deacylhericenone. These findings suggest that the stronger bioactive form of the hericenone C compound is in fact deacylhericenone.


Assuntos
Agaricales , Fator Neurotrófico Derivado do Encéfalo , Humanos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Lipase , Agaricales/química , Ácidos Graxos
3.
RNA Biol ; 18(sup1): 287-302, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130584

RESUMO

The contributions of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) to breast cancer are critical areas of investigation. In this study, we identified a novel lncRNA RP11-283G6.5 which was lowly expressed in breast cancer and whose low expression was correlated with poor overall survival and disease-free survival of breast cancer patients. Functional experiments revealed that ectopic expression of RP11-283G6.5 confined breast cancer cellular growth, migration, and invasion, and promoted cellular apoptosis. Conversely, RP11-283G6.5 silencing facilitated breast cancer cellular growth, migration, and invasion, and repressed cellular apoptosis. Moreover, RP11-283G6.5 was found to confine breast cancer tumour growth and metastasis in vivo. Mechanistically, RP11-283G6.5 competitively bound to ILF3, reduced the binding of ILF3to primary miR-188 (pri-miR-188), abolished the suppressive effect of ILF3 on pri-miR-188 processing, and therefore promoted pri-miR-188 processing, leading to the reduction of pri-miR-188 and the upregulation of mature miR-188-3p. The expression of RP11-283G6.5 was significantly positively correlated with that of miR-188-3p in breast cancer tissues. Through increasing miR-188-3p, RP11-283G6.5 decreased TMED3, a target of miR-188-3p. RP11-283G6.5 further suppressed Wnt/ß-catenin signalling via decreasing TMED3. Rescue assays revealed that inhibition of miR-188-3p, overexpression of TMED3 or blocking Wnt/ß-catenin signalling all attenuated the roles of RP11-283G6.5 in breast cancer. Collectively, these findings demonstrated that RP11-283G6.5 is a tumour suppressive lncRNA in breast cancer via modulating miR-188-3p/TMED3/Wnt/ß-catenin signalling. This study indicated that RP11-283G6.5 might be a promising prognostic biomarker and therapeutic target for breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , Proteínas de Transporte Vesicular/metabolismo , Proteína Wnt1/metabolismo , beta Catenina/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Proteínas de Transporte Vesicular/genética , Proteína Wnt1/genética , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética
4.
Org Biomol Chem ; 17(19): 4789-4800, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31033985

RESUMO

An unexpected time-controlled highly selective C3- or C2-sulfinylation of pyrroles with sulfinamides is reported for the first time. The sulfinylation of indoles with sulfinamides using this protocol is oxidant-free and can be performed under obviously more feasible conditions (1.2 equiv. of indoles, 10 min) in comparison with the precedent procedure (3-20 equiv. of indoles, 16-18 h, ammonium persulfate as oxidant, hv). A variety of functional groups were tolerated, and various C2-thioindoles and C2/3-thiopyrroles were obtained in moderate to excellent yields.

5.
J Nat Prod ; 82(7): 1971-1978, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31244144

RESUMO

Seven new cyclic depsipeptides, clavariopsins C-I (3-9), together with two known congeners, clavariopsins A and B (1 and 2), were isolated from the aquatic hyphomycete Clavariopsis aquatica. Their planar structures, which consist of nine amino acids and one α-hydroxy acid, were elucidated by NMR spectroscopy and HRESIMS. The absolute configurations were established by the advanced Marfey's method and chiral-phase HPLC analysis. Their antifungal and cytotoxic activities were evaluated against six plant pathogenic fungi (Botrytis cinerea, Magnaporthe oryzae, Colletotrichum orbiculare, Fusarium oxysporum, Alternaria alternata, and Aspergillus niger) and a cancer cell line (HeLa-S3), respectively. The majority of the compounds exhibited potent antifungal activity against the fungi tested (minimum inhibition dose = 0.01-10 µg/disk) and induced hyphal swelling in A. niger (minimum effective dose = 0.3-3 µg/disk), whereas the compounds exhibited no cytotoxicity toward the cancer cell line. The results suggest that the clavariopsins could be a promising class of antifungal agents.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Depsipeptídeos/isolamento & purificação , Depsipeptídeos/farmacologia , Fungos Mitospóricos/química , Antifúngicos/química , Antineoplásicos/farmacologia , Depsipeptídeos/química , Células HeLa , Humanos , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
6.
J Cardiovasc Pharmacol ; 69(2): 110-117, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27930430

RESUMO

Clopidogrel (CLO) is a clinical antiplatelet agent, about which there are major concerns because its antiplatelet efficiency decreases with insufficient metabolic activation, leading to "clopidogrel resistance." We aimed to determine the antiplatelet effects of W1, a novel molecule composed of 2-O-clopidogrel and aspirin (1:1 ratio), on platelet aggregation ex vivo and thrombus formation in vivo, and its susceptibility to CLO resistance in combination with other therapies in rats. Platelets were prepared, and an arteriovenous shunt thrombosis model was established using Wistar rats to measure platelet aggregation and thrombus formation, respectively. W1 markedly inhibited adenosine 5'-diphosphate (ADP)-induced platelet aggregation and thrombus formation dose dependently (0.3, 1, and 3 mg/kg). W1 (3 mg/kg) acted rapidly at 0.5 hours and lasted for 72 hours. W1 prolonged bleeding and clotting times in mice, confirming its antithrombotic properties. Compared with CLO 10 mg/kg, the positive control, W1 3 mg/kg exerted equivalent effects on the above specifications. In addition, cyclic adenosine monophosphate levels, measured in rat platelets, increased rapidly after prostaglandin E1 (alprostadil) stimulation of the vehicle control (0.5% methyl cellulose suspension) and W1 (3 mg/kg)-treated groups. ADP (50 µm) reduced the control levels more remarkably than W1 did (P < 0.05 in 3 minutes or P < 0.001 at 5 minutes), suggesting that W1 suppressed ADP-induced cyclic adenosine monophosphate reduction. This was associated with a significant platelet reactivity inhibition measured using the vasodilator-stimulated phosphoprotein assay. CLO or W1 coadministration with or without omeprazole and amlodipine to rats to investigate the pharmacodynamic interactions revealed that W1 exhibited more stable and potent antithrombotic effects than CLO did. In conclusion, both W1 and CLO showed antiplatelet and antithrombotic effects, while the former exhibited less CLO resistance in combination with omeprazole or amlodipine, 2 drugs that inhibit CLO metabolism. Therefore, this study implies that W1 may be a promising oral antiplatelet agent for reducing CLO resistance after percutaneous coronary intervention.


Assuntos
Aspirina/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Ticlopidina/análogos & derivados , Administração Oral , Animais , Aspirina/análogos & derivados , Clopidogrel , Combinação de Medicamentos , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Camundongos , Agregação Plaquetária/fisiologia , Inibidores da Agregação Plaquetária/química , Distribuição Aleatória , Ratos , Ratos Wistar , Ticlopidina/administração & dosagem , Ticlopidina/química
7.
Mol Cell Neurosci ; 75: 1-13, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27343824

RESUMO

Linckosides are members of the steroid glycoside family isolated from the starfish Linckia laevigata. These natural compounds have notable neuritogenic activity and synergistic effects on NGF-induced neuronal differentiation of PC12 cells. Neurogenic factors or molecules that are able to mimic their activities are known to be involved in the survival, proliferation and migration of neurons and glial cells; however how glial cells respond to specific neurogenic molecules such as linckosides has not been investigated. This study aimed to examine the effect of three different linckosides (linckoside A, B and granulatoside A) on the morphological properties, proliferation and migration of human olfactory ensheathing cells (hOECs). The proliferation rate after all the treatments was higher than control as detected by MTS assay. Additionally, hOECs displayed dramatic morphological changes characterized by a higher number of processes after linckoside treatment. Interestingly changes in microtubule organization and expression levels of some early neuronal markers (GAP43 and ßIII-tubulin) were also observed. An increase in the phosphorylation of ERK 1/2 after addition of the compounds suggests that this pathway may be involved in the linckoside-mediated effects particularly those related to morphological changes. These results are the first description of the stimulating effects of linckosides on hOECs and raise the potential for this natural compound or its derivatives to be used to regulate and enhance the therapeutic properties of OECs, particularly for cell transplantation therapies.


Assuntos
Proliferação de Células , Neuroglia/efeitos dos fármacos , Bulbo Olfatório/citologia , Saponinas/farmacologia , Linhagem Celular , Humanos , Microtúbulos/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neuroglia/citologia , Neuroglia/metabolismo , Neuroglia/fisiologia
8.
J Nat Prod ; 78(4): 639-44, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25875311

RESUMO

Four maleic anhydride derivatives, tricladolides A-D (1-4), and three alkylidene succinic acid derivatives, tricladic acids A-C (5-7), were isolated from the aquatic hyphomycete Tricladium castaneicola. The structures of these compounds were determined by spectroscopic analysis, and all were found to be novel. The compounds exhibited inhibitory activity against fungi, particularly Phytophthora sp., a plant pathogen of oomycetes. The inhibitory activity of these metabolites revealed the importance of the cyclic anhydride structure and the lipophilicity of the alkyl side chain. On the other hand, the cytotoxicity of the compounds against B16 melanoma cells indicated that the cyclic anhydride structure was not essential.


Assuntos
Anidridos Maleicos/isolamento & purificação , Anidridos Maleicos/farmacologia , Fungos Mitospóricos/química , Phytophthora/efeitos dos fármacos , Succinatos/isolamento & purificação , Succinatos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Japão , Anidridos Maleicos/química , Melanoma Experimental/tratamento farmacológico , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Relação Estrutura-Atividade , Succinatos/química
9.
Chin Med Sci J ; 30(4): 245-51, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26960306

RESUMO

OBJECTIVE: To explore the effect of atorvastatin on cardiac hypertrophy and to determine the potential mechanism involved. METHODS: An in vitro cardiomyocyte hypertrophy from neonatal rats was induced with angiotensin II (Ang II) stimulation. Before Ang II stimulation, the cultured rat cardiac myocytes were pretreated with atorvastatin at different concentrations (0.1, 1, and 10 µmol/L). The following parameters were evaluated: the myocyte surface area, 3H-leucine incorporation into myocytes, mRNA expressions of atrial natriuretic peptide, brain natriuretic peptide, matrix metalloproteinase 9, matrix metalloproteinase 2, and interleukin-1ß, mRNA and protein expressions of the δ/ß peroxisome proliferator-activated receptor (PPAR) subtypes. RESULTS: It was shown that atorvastatin could ameliorate Ang II-induced neonatal cardiomyocyte hypertrophy in the area of cardiomyocytes, 3H-leucine incorporation, and the expression of atrial natriuretic peptide and brain natriuretic peptide markedly. Meanwhile, atorvastatin also inhibited the augmented mRNA level of several cytokines in hypertrophic myocytes. Furthermore, the down-regulated expression of PPAR- δ/ß at both the mRNA and protein levels in hypertrophic myocytes could be significantly reversed by atorvastatin treatment. CONCLUSIONS: Atorvastatin could improve Ang II-induced cardiac hypertrophy and inhibit the expression of cytokines. Such effect might be partly achieved through activation of the PPAR-δ/ß pathway.


Assuntos
Angiotensina II/farmacologia , Atorvastatina/farmacologia , Cardiomegalia/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , PPAR delta/genética , PPAR beta/genética , Animais , Atorvastatina/uso terapêutico , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Células Cultivadas , Ratos , Ratos Wistar
10.
Commun Med (Lond) ; 4(1): 90, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760506

RESUMO

BACKGROUND: Though deep learning has consistently demonstrated advantages in the automatic interpretation of breast ultrasound images, its black-box nature hinders potential interactions with radiologists, posing obstacles for clinical deployment. METHODS: We proposed a domain knowledge-based interpretable deep learning system for improving breast cancer risk prediction via paired multimodal ultrasound images. The deep learning system was developed on 4320 multimodal breast ultrasound images of 1440 biopsy-confirmed lesions from 1348 prospectively enrolled patients across two hospitals between August 2019 and December 2022. The lesions were allocated to 70% training cohort, 10% validation cohort, and 20% test cohort based on case recruitment date. RESULTS: Here, we show that the interpretable deep learning system can predict breast cancer risk as accurately as experienced radiologists, with an area under the receiver operating characteristic curve of 0.902 (95% confidence interval = 0.882 - 0.921), sensitivity of 75.2%, and specificity of 91.8% on the test cohort. With the aid of the deep learning system, particularly its inherent explainable features, junior radiologists tend to achieve better clinical outcomes, while senior radiologists experience increased confidence levels. Multimodal ultrasound images augmented with domain knowledge-based reasoning cues enable an effective human-machine collaboration at a high level of prediction performance. CONCLUSIONS: Such a clinically applicable deep learning system may be incorporated into future breast cancer screening and support assisted or second-read workflows.


Breast cancer is one of the most common cancers, and finding it early can greatly improve patients' chances of survival and recovery. We create a tool based on artificial intelligence (AI)­whereby computer software learns to perform tasks that normally require human thinking­called MUP-Net. MUP-Net can analyze medical images to predict a patient's risk of having breast cancer. To make this AI tool usable in clinical practice, we enabled doctors to see the reasoning behind the AI's predictions by visualizing the key image features it analyzed. We showed that our AI tool not only makes doctors more confident in their diagnosis but also helps them make better decisions, especially for less experienced doctors. With further testing, our AI tool may help clinicians to diagnose breast cancer more accurately and quickly, potentially improving patient outcomes.

11.
Transl Oncol ; 28: 101615, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36592610

RESUMO

BACKGROUND: Altered epigenetic reprogramming and events contribute to breast cancer (Bca) progression and metastasis. How the epigenetic histone demethylases modulate breast cancer progression remains poorly defined. We aimed to elucidate the biological roles of KDM4A in driving Notch1 activation and Bca progression. METHODS: The KDM4A expression in Bca specimens was analyzed using quantitative PCR and immunohistochemical assays. The biological roles of KDM4A were evaluated using wound-healing assays and an in vivo metastasis model. The Chromatin Immunoprecipitation (ChIP)-qPCR assay was used to determine the role of KDM4A in Notch1 regulation. RESULTS: Here, we screened that targeting KDM4A could induce notable cell growth suppression. KDM4A is required for the growth and progression of Bca cells. High KDM4A enhances tumor migration abilities and in vivo lung metastasis. Bioinformatic analysis suggested that KDM4A was highly expressed in tumors and high KDM4A correlates with poor survival outcomes. KDM4A activates Notch1 expressions via directly binding to the promoters and demethylating H3K9me3 modifications. KDM4A inhibition reduces expressions of a list of Notch1 downstream targets, and ectopic expressions of ICN1 could restore the corresponding levels. KDM4A relies on Notch1 signaling to maintain cell growth, migration and self-renewal capacities. Lastly, we divided a panel of cell lines into KDM4Ahigh and KDM4Alow groups. Targeting Notch1 using specific LY3039478 could efficiently suppress cell growth and colony formation abilities of KDM4Ahigh Bca. CONCLUSION: Taken together, KDM4A could drive Bca progression via triggering the activation of Notch1 pathway by decreasing H3K9me3 levels, highlighting a promising therapeutic target for Bca.

12.
Nat Prod Res ; 37(24): 4089-4098, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36661112

RESUMO

Four new natural compounds named hericenone O (1), hericenone P (2), hericenone Q (3), and hericenone R (4), two of them were reported synthetically (3-4), together with eleven known compounds were isolated from the fruiting bodies of Hericium erinaceus. The chemical structures of the isolated compounds were elucidated by using NMR analysis and mass spectrometry, as well as comparisons with the reported data in the literature. The bioactivity evaluation revealed that hericenone Q showed significant cytotoxic activity against Hep-G2 with IC50 values of 23.89 µM, and against HCT-116 with IC50 values of 65.64 µM.


Assuntos
Antineoplásicos , Basidiomycota , Basidiomycota/química , Benzaldeídos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/análise , Carpóforos/química
13.
Front Oncol ; 13: 1152013, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361565

RESUMO

Background: AI-based clinical decision support system (CDSS) has important prospects in overcoming the current informational challenges that cancer diseases faced, promoting the homogeneous development of standardized treatment among different geographical regions, and reforming the medical model. However, there are still a lack of relevant indicators to comprehensively assess its decision-making quality and clinical impact, which greatly limits the development of its clinical research and clinical application. This study aims to develop and application an assessment system that can comprehensively assess the decision-making quality and clinical impacts of physicians and CDSS. Methods: Enrolled adjuvant treatment decision stage early breast cancer cases were randomly assigned to different decision-making physician panels (each panel consisted of three different seniority physicians in different grades hospitals), each physician made an independent "Initial Decision" and then reviewed the CDSS report online and made a "Final Decision". In addition, the CDSS and guideline expert groups independently review all cases and generate "CDSS Recommendations" and "Guideline Recommendations" respectively. Based on the design framework, a multi-level multi-indicator system including "Decision Concordance", "Calibrated Concordance", " Decision Concordance with High-level Physician", "Consensus Rate", "Decision Stability", "Guideline Conformity", and "Calibrated Conformity" were constructed. Results: 531 cases containing 2124 decision points were enrolled; 27 different seniority physicians from 10 different grades hospitals have generated 6372 decision opinions before and after referring to the "CDSS Recommendations" report respectively. Overall, the calibrated decision concordance was significantly higher for CDSS and provincial-senior physicians (80.9%) than other physicians. At the same time, CDSS has a higher " decision concordance with high-level physician" (76.3%-91.5%) than all physicians. The CDSS had significantly higher guideline conformity than all decision-making physicians and less internal variation, with an overall guideline conformity variance of 17.5% (97.5% vs. 80.0%), a standard deviation variance of 6.6% (1.3% vs. 7.9%), and a mean difference variance of 7.8% (1.5% vs. 9.3%). In addition, provincial-middle seniority physicians had the highest decision stability (54.5%). The overall consensus rate among physicians was 64.2%. Conclusions: There are significant internal variation in the standardization treatment level of different seniority physicians in different geographical regions in the adjuvant treatment of early breast cancer. CDSS has a higher standardization treatment level than all physicians and has the potential to provide immediate decision support to physicians and have a positive impact on standardizing physicians' treatment behaviors.

14.
Analyst ; 137(9): 2218-25, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22434010

RESUMO

1,8-Bis(dimethylamino)naphthalene (DMAN), a classical 'proton sponge', was functionalized on silica particles as a novel solid-phase extraction (SPE) adsorbent (DMAN@silica) for extracting perfluoroalkyl sulfonates (PFSs). High reproducibility and excellent extraction capability for PFSs were obtained in a wide pH range (3.0~8.5). The adsorbed PFSs on DMAN@silica sorbents could be efficiently eluted by 1,8-bis(tetramethylguanidino)naphthalene (TMGN) solution which is a proton sponge with higher proton affinity than DMAN. The elution could be directly analyzed by MALDI-TOF-MS using TMGN as matrix. Clear mass spectra for the PFSs were obtained due to no matrix ions interference observed. Furthermore, a novel strategy based on the DMAN@silica-SPE enrichment, followed by MALDI-TOF-MS analysis, was proposed and applied for PFSs quantification in environmental water samples. The calibration curves of each of the target analytes showed a wide linear dynamic range of response (0.1-10 ng L(-1) for perfluorooctane sulfonate (PFOS), perfluorohexyl sulfonate (PFHxS) and perfluorobutylsulfonate (PFBS)), which were over 2 orders of magnitude. The detection limits for PFOS, PFHxS, and PFBS were 0.021, 0.016, and 0.013 ng L(-1), respectively (S/N = 3). Recoveries of PFOS, PFHxS, and PFBS are in the ranges of 92-104%, 95-102%, and 98-109% for spiked river water samples. These results indicated that the prepared DMAN@silica adsorbents could efficiently enrich PFSs and that the proposed method is reliable.


Assuntos
Meio Ambiente , Prótons , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Ácidos Sulfônicos/análise , Água/química , 1-Naftilamina/análogos & derivados , 1-Naftilamina/química , Adsorção , Concentração de Íons de Hidrogênio , Ácidos Sulfônicos/química , Ácidos Sulfônicos/isolamento & purificação
15.
Pharmacology ; 89(1-2): 74-82, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22343316

RESUMO

AIMS: To investigate the effect of atorvastatin on cardiac aging in rats. MATERIALS: Ninety 20-month-old Wistar rats were administered oral atorvastatin (AVT; 10 or 1 mg·kg(-1)·day(-1)) or saline for 4 months. At the end of the experiment, age-related changes in hearts were measured. RESULTS: Compared with young rats, obvious increases were found in the aging rats in left ventricle thickness, diameter of cardiocytes, collagen deposition, the ratio of type I/type III collagen, ß-galactosidase and malondialdehyde (MDA), and obvious decreases were found in superoxide dismutase (SOD), catalase (CAT) and nitric oxide synthase (NOS). The treatment with AVT led to significant decreases in the thickness of the left ventricle, diameter of cardiocytes, collagen deposition, I/III collagen ratio, MDA, ß-galactosidase and increases in the activity of SOD, CAT and NOS. Some aging-related inflammatory cytokines like interleukin (IL)-1ß, tumour necrosis factor (TNF)-α and matrix metalloproteinase (MMP)-9 were found to be overexpressed in the aging rats. AVT treatment could inhibit the expression of IL-1ß, TNF-α and MMP-9 on both the mRNA and protein levels, and increase the expression of peroxisome proliferator-activated receptors (PPAR-α/ß/δ/γ). Pretreatment with PPAR inhibitors attenuated the inhibitory effect of AVT on the expression of inflammatory cytokines. CONCLUSION: AVT may retard the cardiac aging process by upregulating PPARs.


Assuntos
Envelhecimento/efeitos dos fármacos , Coração/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Miocárdio/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/biossíntese , Pirróis/farmacologia , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Animais , Anticolesterolemiantes/farmacologia , Atorvastatina , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Coração/fisiologia , Mediadores da Inflamação/metabolismo , Oxirredutases/biossíntese , Receptores Ativados por Proliferador de Peroxissomo/antagonistas & inibidores , Ratos , Ratos Wistar , Regulação para Cima/efeitos dos fármacos
16.
Analyst ; 136(11): 2225-9, 2011 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21468431

RESUMO

Triphenylsulfonium chloride (TPSC) was employed as a bifunctional agent for the selective enrichment of perfluoroalkyl sulfonates by triphenylsulfonium perfluorosulfonic acid (TPA, a photoacid generator) precipitation, and for the direct detection of perfluorosulfonic acid by MALDI-TOF-MS, using the triphensylsulfonium group of TPA as a matrix.


Assuntos
Alcanossulfonatos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Fotólise , Compostos de Sulfônio/química
17.
Front Oncol ; 11: 621914, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026607

RESUMO

BACKGROUND: The naked-eye invisibility of indocyanine green fluorescence limits the application of near-infrared fluorescence imaging (NIR) systems for real-time navigation during sentinel lymph node biopsy (SLNB) in patients with breast cancer undergoing surgery. This study aims to evaluate the effectiveness and safety of a novel NIR system in visualizing indocyanine green fluorescence images in the surgical field and the application value of combined methylene blue (MB) and the novel NIR system in SLNB. METHODS: Sixty patients with clinical node-negative breast cancer received indocyanine green (ICG) and MB as tracers. Two NIR system instruments, namely, lymphatic fluorescence imaging system (LFIS) designed by the University of Science and Technology of China and vascular imager by Langfang Mingde Medical Biotechnology Co., Ltd. (Langfang vascular imager), were used as navigation assistance to locate sentinel lymph nodes (SLNs). Excising the lymph nodes developed by both MB and ICG by two NIR systems or palpably suspicious as SLNs and undergoing rapid pathological examination. RESULTS: Both instruments exhibited 95% (57/60) success for real-time lymphatic fluorescent images. A total of 186 SLNs were identified, of which two were pathologically confirmed as lacking any lymph node tissue. SLN identification rate was 100% (184/184) for MB plus LFIS and 86.96% (160/184) for MB alone. The median number of SLNs identified by LFIS combined with MB was 3 (range of 1-8), which was significantly higher than that by MB alone at 2 (range 1-7) (P<0.05). CONCLUSION: LFIS effectively detects SLNs in breast cancer, projects the fluorescence signals during surgery, and provides a continuous surgical navigation system without the need for a remote monitor. The ICG method navigated by combined LFIS and MB may be a promising alternative tracer for radioisotope in SLN mapping. CLINICAL TRIAL REGISTRATION: This clinical trial was registered with the China Clinical Trial Center, registration number ChiCTR2000039542.

18.
Nat Biomed Eng ; 5(6): 522-532, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33875840

RESUMO

The clinical application of breast ultrasound for the assessment of cancer risk and of deep learning for the classification of breast-ultrasound images has been hindered by inter-grader variability and high false positive rates and by deep-learning models that do not follow Breast Imaging Reporting and Data System (BI-RADS) standards, lack explainability features and have not been tested prospectively. Here, we show that an explainable deep-learning system trained on 10,815 multimodal breast-ultrasound images of 721 biopsy-confirmed lesions from 634 patients across two hospitals and prospectively tested on 912 additional images of 152 lesions from 141 patients predicts BI-RADS scores for breast cancer as accurately as experienced radiologists, with areas under the receiver operating curve of 0.922 (95% confidence interval (CI) = 0.868-0.959) for bimodal images and 0.955 (95% CI = 0.909-0.982) for multimodal images. Multimodal multiview breast-ultrasound images augmented with heatmaps for malignancy risk predicted via deep learning may facilitate the adoption of ultrasound imaging in screening mammography workflows.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/estatística & dados numéricos , Mamografia/normas , Ultrassonografia/normas , Adulto , Neoplasias da Mama/patologia , Conjuntos de Dados como Assunto , Reações Falso-Positivas , Feminino , Humanos , Mamografia/métodos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Ultrassonografia/métodos
19.
Chem Rec ; 10(2): 57-69, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20333719

RESUMO

Symbiotic relationships play critical roles in marine ecosystems. Among symbionts, marine dinoflagellates have attracted the attention of natural products chemists, biologists, and ecologists, since they are rich sources of unique bioactive secondary metabolites. The polyol compound symbiodinolide, which was isolated from the symbiotic dinoflagellate Symbiodinium sp., exhibits significant voltage-dependent N-type Ca(2+) channel-opening activity and may serve as a defense substance to prevent digestion of the host animals. Durinskiols are also unique long carbon-chain polyol compounds that were isolated from the dinoflagellate Durinskia sp. We found a selective cleavage reaction of allylic 1,2-diol using an olefin metathesis catalyst, and developed a fluorescent-labeling method for MS/MS analysis to achieve the structural elucidation of huge polyol compounds. This review highlights recent advances in structural and biological studies on symbiodinolide, durinskiols, and related polyol compounds.


Assuntos
Dinoflagellida/metabolismo , Compostos Macrocíclicos/metabolismo , Dinoflagellida/química , Compostos Macrocíclicos/química , Simbiose
20.
J Neurochem ; 107(5): 1248-60, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18796006

RESUMO

Neurotrophins, such as the nerve growth factor (NGF), play an essential role in the growth, development, survival and functional maintenance of neurons in the central and peripheral systems. They also prevent neuronal cell death under various stressful conditions, such as ischemia and neurodegenerative disorders. NGF induces cell differentiation and neurite outgrowth by binding with and activating the NGF receptor tyrosine kinase followed by activation of a variety of signaling cascades. We have investigated the NGF-dependent neuritogenesis enhancer potential of a food-derived small molecule contained in Brassica vegetables and identified the protein tyrosine phosphatase (PTP) 1B as a key regulator of the NGF receptor-initiated signal transduction. Based on an extensive screening of Brassica vegetable extracts for the neuritogenic-promoting activity in the rat pheochromocytoma cell line PC12, we found the Japanese horseradish, wasabi (Wasabia japonica, syn. Eutrema wasabi), as the richest source and identified 6-methylsulfinylhexyl isothiocyanate (6-HITC), an analogue of sulforaphane isolated from broccoli, as one of the major neuritogenic enhancers in the wasabi. 6-HITC strongly enhanced the neurite outgrowth and neurofilament expression elicited by a low-concentration of NGF that alone was insufficient to induce neuronal differentiation. 6-HITC also facilitated the sustained-phosphorylation of the extracellular signal-regulated kinase and the autophosphorylation of the NGF receptor TrkA. It was found that PTP1B act as a phosphatase capable of dephosphorylating Tyr-490 of TrkA and was inactivated by 6-HITC in a redox-dependent manner. The identification of PTP1B as a regulator of NGF signaling may provide new clues about the chemoprotective potential of food components, such as isothiocyanates.


Assuntos
Fator de Crescimento Neural/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Receptor trkA/fisiologia , Transdução de Sinais/fisiologia , Animais , Biotinilação/métodos , Cisteína/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Peróxido de Hidrogênio/farmacologia , Isotiocianatos/farmacologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fator de Crescimento Neural/química , Fator de Crescimento Neural/farmacologia , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Oxidantes/farmacologia , Células PC12 , Fosforilação/efeitos dos fármacos , RNA Interferente Pequeno/genética , Ratos , Receptor trkA/biossíntese , Receptor trkA/genética , Transdução de Sinais/efeitos dos fármacos , Transfecção
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