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1.
Ecotoxicol Environ Saf ; 273: 116161, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430581

RESUMO

Di(2-ethylhexyl) phthalate (DEHP) is a worldwide common plasticizer. Nevertheless, DEHP is easily leached out to the environment due to the lack of covalent bonds with plastic. High dose of DEHP exposure is often observed in hemodialysis patients because of the continual usage of plastic medical devices. Although the liver is the major organ that catabolizes DEHP, the impact of long-term DEHP exposure on the sensitivity of liver cancer to chemotherapy remains unclear. In this study, we established long-term DEHP-exposed hepatocellular carcinoma (HCC) cells and two NOD/SCID mice models to investigate the effects and the underlying mechanisms of long-term DEHP exposure on chemosensitivity of HCC. The results showed long-term DEHP exposure potentially increased epithelial-mesenchymal transition (EMT) in HCC cells. Next generation sequencing showed that long-term DEHP exposure increased cell adhesion/migratory related genes expression and blunted sorafenib treatment induced genes alterations. Long-term exposure to DEHP reduced the sensitivity of HCC cells to sorafenib-induced anti-migratory effect by enhancing the EMT transcription factors (slug, twist, and ZEB1) and mesenchymal protein (vimentin) expression. In NOD/SCID mice model, we showed that long-term DEHP-exposed HCC cells exhibited higher growth rate. Regarding the anti-HCC effects of sorafenib, subcutaneous HuH7 tumor grew slowly in sorafenib-treated mice. Nonetheless, the anti-tumor growth effect of sorafenib was not observed in long-term DEHP-exposed mice. Higher mesenchymal markers and proliferating cell nuclear antigen (PCNA) expression were found in sorafenib-treated long-term DEHP-exposed mice. In conclusion, long-term DEHP exposure promoted migratory activity in HCC cells and decreased sorafenib sensitivity in tumor-bearing mice.


Assuntos
Carcinoma Hepatocelular , Dietilexilftalato , Neoplasias Hepáticas , Ácidos Ftálicos , Humanos , Camundongos , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Dietilexilftalato/toxicidade , Camundongos SCID , Camundongos Endogâmicos NOD , Resultado do Tratamento
2.
J Nutr Biochem ; 125: 109565, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38176621

RESUMO

Various endogenous and exogenous stimuli can result in an inflammatory response and collagen deposition in the liver, which affect liver function and increase the risk of developing liver cirrhosis and cancer. Rice bran, the main by-product of rice milling, contains various nutrients which possess hepatoprotective activities. In this study, we investigated the effects of rice bran on carbon tetrachloride (CCl4)-induced liver fibrosis in mice. Mice were fed a rice-bran-containing diet (10% rice bran w/w) or a standard diet with or without an injection of 20% CCl4 to induce liver fibrosis. Our results showed that feeding a rice-bran-containing diet could alleviate CCl4-induced liver damage, collagen deposition, and expressions of fibrosis-related genes, including α-smooth muscle actin (α-SMA), collagen 1a2 (COL1A2), and transforming growth factor-ß (TGF-ß) in liver tissues. Moreover, consumption of rice bran enhanced phase II detoxification and antioxidant gene expressions, including Gsta3, Gstp1, Catalase, SOD1, SOD2, and SOD3. Treatment with γ-oryzanol, the major bioactive compound in rice bran, decreased the sensitivity of hepatic stellate cells (HSCs) to TGF-ß1-induced α-SMA, COL1A2, and phosphorylated smad2 expressions. In conclusion, a rice-bran-containing diet may have beneficial effects on liver fibrogenesis through increased antioxidant and detoxification activities. γ-Oryzanol, the major bioactive compound of rice bran, can inhibit activation of HSCs.


Assuntos
Antioxidantes , Oryza , Fenilpropionatos , Animais , Camundongos , Antioxidantes/metabolismo , Oryza/metabolismo , Células Estreladas do Fígado/metabolismo , Transdução de Sinais , Cirrose Hepática/metabolismo , Fígado/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Dieta , Tetracloreto de Carbono/toxicidade
3.
Life Sci ; 336: 122327, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38061536

RESUMO

INTRODUCTION: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, often accompanied by obesity, diabetes, and increased risks of depression and anxiety. Currently, there are no FDA-approved drugs to treat NAFLD and its related systemic symptoms. Previously, we identified a new barbituric acid derivative (BA-5) that expressed effectiveness against fibrosis and drug-resistant hepatocellular carcinoma. AIMS: This study investigated the potential of BA-5 against high-fat diet (HFD)-induced NAFLD and mood disorders in mice. MAIN METHODS: Six-weeks-old male C57BL/6 mice were fed with a 45 % HFD for 8 weeks to induce NAFLD and associated metabolic disorders. Mice were treated with a BA-5 and the therapeutic effects and the underlying molecular mechanisms were investigated. KEY FINDINGS: Administration of BA-5 significantly reduced serum levels of alanine aminotransferase (ALT), low-density lipoprotein (LDL), fatty acids (FA), and triglycerides (TG) in HFD-fed mice. BA-5 treatment decreased expressions of hepatic lipogenesis-related markers (acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and ATP-citrate lyase (ACLY)), increased fatty acid oxidation markers (carnitine palmitoyltransferase 1A (CPT1A) and acyl-CoA oxidase 1 (ACOX1)), and attenuated hepatic fat accumulation in HFD-fed mice. Moreover, HFD-induced adipocyte size enlargement and activation of lipolysis markers such as phosphorylated (p)-hormone-sensitive lipase (HSL) 565, p-HSL 660, and perilipin were inhibited in BA-5-treated mice. Notably, HFD-induced anxiety- and depression-like behaviors significantly improved in the BA-5 treated group through enhanced anti-inflammatory responses in the hippocampus. SIGNIFICANCE: This study provides new insights into clinical therapeutic strategies of barbituric acid derivatives for HFD-induced NAFLD and associated mood disturbances.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Dieta Hiperlipídica/efeitos adversos
4.
Bioengineering (Basel) ; 10(9)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37760177

RESUMO

The increased proliferation and activation of hepatic stellate cells (HSCs) are associated with liver fibrosis development. To date, there are no FDA-approved drugs for the treatment of liver cirrhosis. Augmentation of HSCs apoptosis is one of the resolutions for liver fibrosis. In this study, we extracted α-mangostin (1,3,6-trihydroxy-7-methoxy-2,8-bis(3-methyl-2-butenyl)-9H-xanthen-9-one) from the fruit waste components of mangosteen pericarp. The isolated α-mangostin structure was determined and characterized with nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS) and compared with those known compounds. The intracellular signaling pathway activities of α-mangostin on Transforming growth factors-beta 1 (TGF-ß1) or Platelet-derived growth factor subunit B (PDGF-BB) induced HSCs activation and were analyzed via Western blot and Real-time Quantitative Polymerase Chain Reaction (Q-PCR). α-Mangostin-induced mitochondrial dysfunction and apoptosis in HSCs were measured by seahorse assay and caspase-dependent cleavage. The in vivo anti-fibrotic effect of α-mangostin was assessed by carbon tetrachloride (CCl4) treatment mouse model. The data showed that α-mangostin treatment inhibited TGF-ß1-induced Smad2/3 phosphorylation and alpha-smooth muscle actin (α-SMA) expression in HSCs in a dose-dependent manner. Regarding the PDGF-BB-induced HSCs proliferation signaling pathways, α-mangostin pretreatment suppressed the phosphorylation of extracellular-signal-regulated kinase (ERK) and p38. The activation of caspase-dependent apoptosis and dysfunction of mitochondrial respiration (such as oxygen consumption rate, ATP production, and maximal respiratory capacity) were observed in α-mangostin-treated HSCs. The CCl4-induced liver fibrosis mouse model showed that the administration of α-mangostin significantly decreased the expression of the fibrosis markers (α-SMA, collagen-a2 (col1a2), desmin and matrix metalloproteinase-2 (MMP-2)) as well as attenuated hepatic collagen deposition and liver damage. In conclusion, this study demonstrates that α-mangostin attenuates the progression of liver fibrosis through inhibiting the proliferation of HSCs and triggering apoptosis signals. Thus, α-mangostin may be used as a potential novel therapeutic agent against liver fibrosis.

5.
Biomed Pharmacother ; 166: 115293, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37567069

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor. Although sorafenib and regorafenib have been approved for first-line and second-line treatment, respectively, of patients with advanced HCC, long-term treatment often results in acquired resistance. Given that glycolysis-mediated lactate production can contribute to drug resistance and impair HCC treatment efficacy, we investigated the effects of ketone body treatment on the metabolic shift in sorafenib-resistant HCC cells. We discovered differential expression of 3-hydroxymethyl glutaryl-CoA synthase 2 (HMGCS2) and the ketone body D-ß-hydroxybutyrate (ß-HB) in four sorafenib-resistant HCC cell lines. In sorafenib-resistant HCC cells, lower HMGCS2 and ß-HB levels were correlated with more glycolytic alterations and higher lactate production. ß-HB treatment enhanced pyruvate dehydrogenase (PDH) expression and decreased lactate dehydrogenase (LDHA) expression and lactate production in sorafenib-resistant HCC cells. Additionally, ß-HB combined with sorafenib or regorafenib promoted the antiproliferative and antimigratory abilities of sorafenib-resistant HCC cells by inhibiting the B-raf/mitogen-activated protein kinase pathway and mesenchymal N-cadherin-vimentin axis. Although the in vivo ß-HB administration did not affect tumor growth, the expression of proliferative and glycolytic proteins was inhibited in subcutaneous sorafenib-resistant tumors. In conclusion, exogenous ß-HB treatment can reduce lactate production and reverse sorafenib resistance by inducing a glycolytic shift; it can also synergize with regorafenib for treating sorafenib-resistant HCC.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Carcinoma Hepatocelular/patologia , Ácido 3-Hidroxibutírico , Neoplasias Hepáticas/patologia , Resistencia a Medicamentos Antineoplásicos , Glicólise , Lactatos/farmacologia , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
6.
J Nutr Biochem ; 115: 109267, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36641072

RESUMO

Deep-frying is a common cooking practice worldwide, and after repeated heating's, the oil undergoes various chemical reactions, including hydrolysis, polymerization, lipid oxidation, and the Maillard reaction. Studies have pointed out that oxidized dietary frying oil may cause teratogenesis in mice and increase cancer and cardiovascular risks. The liver is the main organ involved in dietary nutrient catabolism, detoxification, bile production, and lipid metabolism. Nevertheless, the effects of oxidized frying oil exposure on the activation of hepatic stellate cells (HSCs) and liver fibrosis are still unclear. In this study, we showed that exposure to oxidized frying oil enhanced the sensitivity of HSCs to transforming growth factor (TGF)-ß1-induced α-smooth muscle actin (α-SMA), collagen 1a2, collagen 1a1, metalloproteinase-2, and phosphorylated smad2/3 activation. In both carbon tetrachloride (CCl4)- and thioacetamide (TAA)-induced liver fibrosis mouse models, we showed that long-term administration of a 10% fried oil-containing diet significantly upregulated fibrogenesis genes expression and deposition of hepatic collagen. Furthermore, long-term fried oil exposure not only promoted macrophage infiltration and increased inflammatory-related gene expression, but also accumulated excess cholesterol and lipid peroxidation in the liver tissues. In conclusion, our study demonstrated that feeding a fried oil-containing diet may trigger TGF-ß1-induced HSCs activation and thereby promote liver damage and fibrosis progression through enhancing the inflammatory response and lipid peroxidation.


Assuntos
Gorduras Insaturadas na Dieta , Células Estreladas do Fígado , Camundongos , Animais , Células Estreladas do Fígado/metabolismo , Tetracloreto de Carbono/efeitos adversos , Tioacetamida/toxicidade , Tioacetamida/metabolismo , Gorduras Insaturadas na Dieta/efeitos adversos , Metaloproteinase 2 da Matriz/metabolismo , Cirrose Hepática/metabolismo , Fígado/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
7.
Molecules ; 27(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36432116

RESUMO

Primary liver cancer is the fifth leading death of cancers in men, and hepatocellular carcinoma (HCC) accounts for approximately 90% of all primary liver cancer cases. Sorafenib is a first-line drug for advanced-stage HCC patients. Sorafenib is a multi-target kinase inhibitor that blocks tumor cell proliferation and angiogenesis. Despite sorafenib treatment extending survival, some patients experience side effects, and sorafenib resistance does occur. 3-Hydroxymethyl glutaryl-CoA synthase 2 (HMGCS2) is the rate-limiting enzyme for ketogenesis, which synthesizes the ketone bodies, ß-hydroxybutyrate (ß-HB) and acetoacetate (AcAc). ß-HB is the most abundant ketone body which is present in a 4:1 ratio compared to AcAc. Recently, ketone body treatment was found to have therapeutic effects against many cancers by causing metabolic alternations and cancer cell apoptosis. Our previous publication showed that HMGCS2 downregulation-mediated ketone body reduction promoted HCC clinicopathological progression through regulating c-Myc/cyclin D1 and caspase-dependent signaling. However, whether HMGCS2-regulated ketone body production alters the sensitivity of human HCC to sorafenib treatment remains unclear. In this study, we showed that HMGCS2 downregulation enhanced the proliferative ability and attenuated the cytotoxic effects of sorafenib by activating expressions of phosphorylated (p)-extracellular signal-regulated kinase (ERK), p-P38, and p-AKT. In contrast, HMGCS2 overexpression decreased cell proliferation and enhanced the cytotoxic effects of sorafenib in HCC cells by inhibiting ERK activation. Furthermore, we showed that knockdown HMGCS2 exhibited the potential migratory ability, as well as decreasing zonula occludens protein (ZO)-1 and increasing c-Myc expression in both sorafenib-treated Huh7 and HepG2 cells. Although HMGCS2 overexpression did not alter the migratory effect, expressions of ZO-1, c-Myc, and N-cadherin decreased in sorafenib-treated HMGCS2-overexpressing HCC cells. Finally, we investigated whether ketone treatment influences sorafenib sensitivity. We showed that ß-HB pretreatment decreased cell proliferation and enhanced antiproliferative effect of sorafenib in both Huh7 and HepG2 cells. In conclusion, this study defined the impacts of HMGCS2 expression and ketone body treatment on influencing the sorafenib sensitivity of liver cancer cells.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Cetonas/uso terapêutico , Neoplasias Hepáticas/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Corpos Cetônicos/metabolismo , Corpos Cetônicos/uso terapêutico , MAP Quinases Reguladas por Sinal Extracelular , Resultado do Tratamento
8.
BMC Med Educ ; 22(1): 207, 2022 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-35346161

RESUMO

BACKGROUND: As ultrasound has become increasingly prominent in medicine, portable ultrasound is perceived as the visual stethoscope of the twenty-first century. Many studies have shown that exposing preclinical students to ultrasound training can increase their motivation and ultrasound competency. However, few studies have discussed the effect of ultrasound training on anatomy learning. METHOD: The Parallel Ultrasound Hands-on (PUSH) course was designed to investigate whether or not ultrasonography training affects anatomy knowledge acquisition. The PUSH course included anatomical structures located in the chest and abdomen (target anatomy) and was conducted in parallel to the compulsory gross anatomy course. Learners (n = 140) voluntarily participated in this elective course (learners in the course before the midterm examination (Group 1, n = 69), or after the midterm examination (Group 2, n = 71)). Anatomy examination scores (written and laboratory tests) were utilized to compare the effects of the PUSH course. RESULT: Group 1 obtained significantly higher written test scores on the midterm examination (mean difference [MD] = 1.5(7.6%), P = 0.014, Cohen's d = 0.43). There was no significant difference in the final examination scores between the two groups (Written Test: MD = 0.3(1.6%), P = 0.472). In Laboratory test, both mid-term (MD:0.7(2.8%), P = 0.308) and final examination (MD:0.3(1.5%), P = 0.592) showed no significant difference between two groups. Students provided positive feedback in overall learning self-efficacy after the PUSH course (Mean = 3.68, SD = ±0.56 on a 5-point Likert scale). Learning self-efficacy in the cognitive domain was significantly higher than that in the affective domain (MD = 0.58; P < 0.001) and psychomotor domain (MD = 0.12; P = 0.011). CONCLUSION: The PUSH course featured a hands-on learning design that empowered medical students to improve their anatomy learning.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Currículo , Avaliação Educacional , Humanos , Estudantes de Medicina/psicologia , Ultrassonografia
9.
PLoS One ; 16(9): e0257887, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34582505

RESUMO

STUDY OBJECTIVE: The purpose of this feasibility study is to develop and validate a new assessment tool and scoring system for multitasking competency for physicians in-training in a timed simulated setting. The multitasking competency includes ability to appropriately prioritize and implement tasks for different patients who present simultaneously. METHODS: We designed three single task stations with different levels of difficulty and priority. These skill stations were then combined to create a multitasking simulation scenario. Skill checklists and the global rating scale were utilized to assess the participants' performance. A multitasking score, multitasking index, and priority score were developed to measure the multitasking ability of participants. RESULTS: Thirty-three first-year postgraduate physicians were recruited for this prospective study. The total performance scores were significantly higher for the single-tasking stations than for the multitasking scenario. In terms of the time needed to complete the tasks, the participants spent more time on the multitasking scenario than on the single-tasking scenario. There were significant correlations between the global rating scale and the multitasking score (rho = 0.693, p < 0.001) and between the global rating scale and the multitasking index (rho = 0.515, p < 0.001). The multitasking score, multitasking index, and priority score did not have any significant correlations with the total single-tasking score. CONCLUSION: We demonstrated that the use of a simulated multitasking scenario could be an effective method of assessing multitasking ability and allow assessors to offer better quality feedback.


Assuntos
Competência Clínica , Medicina de Emergência/educação , Adulto , Simulação por Computador , Estudos de Viabilidade , Feminino , Humanos , Masculino , Comportamento Multitarefa , Estudos Prospectivos
10.
Sci Rep ; 11(1): 16491, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389760

RESUMO

This paper presents an autonomous navigation system for cost-effective magnetic-assisted colonoscopy, employing force-based sensors, an actuator, a proportional-integrator controller and a real-time heuristic searching method. The force sensing system uses load cells installed between the robotic arm and external permanent magnets to derive attractive force data as the basis for real-time surgical safety monitoring and tracking information to navigate the disposable magnetic colonoscope. The average tracking accuracy on magnetic field navigator (MFN) platform in x-axis and y-axis are 1.14 ± 0.59 mm and 1.61 ± 0.45 mm, respectively, presented in mean error ± standard deviation. The average detectable radius of the tracking system is 15 cm. Three simulations of path planning algorithms are presented and the learning real-time A* (LRTA*) algorithm with our proposed directional heuristic evaluation design has the best performance. It takes 75 steps to complete the traveling in unknown synthetic colon map. By integrating the force-based sensing technology and LRTA* path planning algorithm, the average time required to complete autonomous navigation of a highly realistic colonoscopy training model on the MFN platform is 15 min 38 s and the intubation rate is 83.33%. All autonomous navigation experiments are completed without intervention by the operator.

11.
Biology (Basel) ; 10(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34356509

RESUMO

Monocyte chemoattractant protein-1-induced protein 1 (MCPIP1) is rapidly produced under proinflammatory stimuli, thereby feeding back to downregulate excessive inflammation. In this study, we used the stable, inducible expressions of wild-type (WT) MCPIP1 and an MCPIP1-D141N mutant in T-REx-293 cells by means of a tetracycline on (Tet-on) system. We found that WT MCPIP1 but not MCPIP1-D141N mutant expression dramatically increased apoptosis, caspase-3, -7, -8, and -9 activation, and c-Jun N-terminal kinase (JNK) phosphorylation in TNF-α-treated cells. The pan-caspase inhibitor, z-VAD-fmk, and the caspase-1 inhibitor, z-YVAD-fmk, but not the JNK inhibitor, SP600125, significantly reversed apoptosis and caspase activation in TNF-α/MCPIP1-treated cells. Surprisingly, MCPIP1 itself was also cleaved, and the cleavage was suppressed by treatment with the pan-caspase inhibitor and caspase-1 inhibitor. Moreover, MCPIP1 was found to contain a caspase-1/-4 consensus recognition sequence located in residues 234~238. As expected, the WT MCPIP1 but not the MCPIP1-D141N mutant suppressed NF-κB activation, as evidenced by inhibition of IκB kinase (IKK) phosphorylation and IκB degradation using Western blotting, IKK activity using in vitro kinase activity, and NF-κB translocation to nuclei using an immunofluorescence assay. Interestingly, MCPIP1 also significantly inhibited importin α3 and importin α4 expressions, which are major nuclear transporter receptors for NF-κB. Inhibition of NF-κB activation further downregulated expression of the caspase-8 inhibitor, cFLIP. In summary, the results suggest that MCPIP1 could enhance the TNF-α-induced apoptotic pathway through decreasing NF-κB activation and cFLIP expression.

12.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445279

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor in the world. Sorafenib is the first-line drug for patients with advanced HCC. However, long-term treatment with sorafenib often results in reduced sensitivity of tumor cells to the drug, leading to acquired resistance. Identifying biomarkers which can predict the response to sorafenib treatment may represent a clinical challenge in the personalized treatment era. Niemann-Pick type C2 (NPC2), a secretory glycoprotein, plays an important role in regulating intracellular free cholesterol homeostasis. In HCC patients, downregulation of hepatic NPC2 is correlated with poor clinical pathological features through regulating mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) activation. This study aimed to investigate the roles of secretory NPC2-mediated free cholesterol levels as biomarkers when undergoing sorafenib treatment and evaluate its impact on acquired sorafenib resistance in HCC cells. Herein, we showed that NPC2 downregulation and free cholesterol accumulation weakened sorafenib's efficacy through enhancing MAPK/AKT signaling in HCC cells. Meanwhile, NPC2 overexpression slightly enhanced the sorafenib-induced cytotoxic effect. Compared to normal diet feeding, mice fed a high-cholesterol diet had much higher tumor growth rates, whereas treatment with the free cholesterol-lowering agent, hydroxypropyl-ß-cyclodextrin, enhanced sorafenib's tumor-inhibiting ability. In addition, sorafenib treatment induced higher NPC2 secretion, which was mediated by inhibition of the Ras/Raf/MAPK kinase (MEK)/ERK signaling pathway in HCC cells. In both acquired sorafenib-resistant cell and xenograft models, NPC2 and free cholesterol secretion were increased in culture supernatant and serum samples. In conclusion, NPC2-mediated free cholesterol secretion may represent a candidate biomarker for the likelihood of HCC cells developing resistance to sorafenib.


Assuntos
Carcinoma Hepatocelular/metabolismo , Colesterol/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Sorafenibe/farmacologia , Proteínas de Transporte Vesicular/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Feminino , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
13.
BMC Med Educ ; 21(1): 438, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34412610

RESUMO

BACKGROUND: In recent years, point-of-care ultrasound (POCUS) has become an essential field of medical education. Bedside ultrasound has become a necessary skill for clinical physicians. Previous studies have already discussed the importance of advancements in ultrasound education. However, learning motivations for ultrasound education have seldom been analyzed in the literature. For medical students, learning ultrasound could have a relevance for their future career. The Existence, Relatedness and Growth (ERG) theory extended Maslow's hierarchy of needs through these three concepts. This theory has been widely used in the workplace to analyze employee job performance but has not yet been applied in medical education. In this study ERG theory was applied to analyze pre-clinical medical students' learning motivation toward ultrasound education. METHOD: This mixed method study used online questionnaires consisting of open-ended questions as a data collection tool, and based on these results, both qualitative and quantitative analysis were conducted. Participants answered a series of neutral and open-ended questions regarding their motivations to learn ultrasonography. After data collection, a three-step analysis was conducted based on the grounded theory approach. Finally, the results of the thematic coding were used to complete additional quantitative analysis. RESULTS: The study involved 140 pre-clinical medical students, and their responses fell into 13 specific categories. The analysis demonstrated that students' motivations toward ultrasound education were unbalanced across the three ERG domains (F = 41.257, p < .001). Pairwise comparisons showed that students mentioned existence motivation (MD = 39.3%; p < .001) and growth motivation (MD = 40.7%; p < .001) more frequently than relatedness motivation. However, there was no significant difference between existence motivation and growth motivation (MD = - 1.4%; p = .830). CONCLUSION: The results revealed that students placed a high value on existence and growth needs rather than relatedness based on the survey. In addition, the findings suggest that ERG theory can be a useful tool to conduct medical education motivation analysis.


Assuntos
Motivação , Estudantes de Medicina , Humanos , Aprendizagem , Autonomia Pessoal , Regulador Transcricional ERG , Ultrassonografia
14.
Sci Rep ; 11(1): 6460, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33742067

RESUMO

We developed a magnetic-assisted capsule colonoscope system with integration of computer vision-based object detection and an alignment control scheme. Two convolutional neural network models A and B for lumen identification were trained on an endoscopic dataset of 9080 images. In the lumen alignment experiment, models C and D used a simulated dataset of 8414 images. The models were evaluated using validation indexes for recall (R), precision (P), mean average precision (mAP), and F1 score. Predictive performance was evaluated with the area under the P-R curve. Adjustments of pitch and yaw angles and alignment control time were analyzed in the alignment experiment. Model D had the best predictive performance. Its R, P, mAP, and F1 score were 0.964, 0.961, 0.961, and 0.963, respectively, when the area of overlap/area of union was at 0.3. In the lumen alignment experiment, the mean degrees of adjustment for yaw and pitch in 160 trials were 21.70° and 13.78°, respectively. Mean alignment control time was 0.902 s. Finally, we compared the cecal intubation time between semi-automated and manual navigation in 20 trials. The average cecal intubation time of manual navigation and semi-automated navigation were 9 min 28.41 s and 7 min 23.61 s, respectively. The automatic lumen detection model, which was trained using a deep learning algorithm, demonstrated high performance in each validation index.


Assuntos
Colonoscópios/normas , Automação , Ceco/diagnóstico por imagem , Ceco/patologia , Colonoscopia/instrumentação , Colonoscopia/métodos , Diagnóstico por Computador/métodos , Diagnóstico por Computador/normas , Desenho de Equipamento , Humanos , Fenômenos Magnéticos , Sensibilidade e Especificidade
15.
PLoS One ; 15(11): e0242731, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33227037

RESUMO

PURPOSE: The use of Virtual Reality (VR) in health professions education has increased dramatically in recent years, yet there is limited evidence of its impact on educational outcomes. The purpose of the study was to assess the impact of VR anatomy instruction on the ultrasound competency of novice learners participating in a ultrasonography workshop. METHOD: We designed a VR-enhanced ultrasonography training program and utilized a plane transection tool to interact with a three-dimensional (3D) VR model of the human body which facilitated the 3D conceptualization of the spatial relationship of anatomical structures, leading to faster and better development of ultrasonographic competency. This was a randomized control study which enrolled third-year medical students (n = 101) without previous exposure to formal or informal ultrasonography training. The participants were randomly divided into an intervention and control group. We assessed participants' competency through ultrasound performance stations on live subjects, we also measured anatomical and ultrasound image identification ability using multiple choice tests. RESULT: Participants in the intervention group (median = 16; interquartile 13 to 19) had significantly higher scores in ultrasonography task performance tests than the control group (median = 10; interquartile 7 to 14; Mann-Whitney U = 595; P < 0.01). In sub-group analysis, the intervention group performed significantly better in the six out of ten ultrasound tasks. Participants in the intervention group also had greater improvement in ultrasonographic image identification MCQ tests than the control group (Mann-Whitney U = 914; P < 0.05). CONCLUSION: This study suggests that VR-enhanced anatomical training could be of significant benefit in ultrasonography training by promoting a better understanding of the spatial relationships of anatomical structures and the development of early psychomotor skills transferable to the handling of ultrasonographic probes.


Assuntos
Anatomia/educação , Competência Clínica , Estudantes de Medicina , Realidade Virtual , Adulto , Feminino , Humanos , Masculino , Ultrassonografia
18.
Cancers (Basel) ; 12(7)2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32635582

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary malignant liver tumor with limited treatment. The ketogenic diet (KD) emerged as a metabolic therapy for cancer; however, the antitumor effect on HCC remains controversial. We previously reported that the ketogenesis rate-limiting enzyme, 3-hydroxymethylglutaryl-CoA synthase 2 (HMGCS2), was downregulated in most patients with HCC. The knockdown of HMGCS2 enhanced the proliferation and metastasis ability of HCC cells. However, the role of HMGCS2 in affecting KD-mediated metabolic effects remains unclear. Here, we report that KD feeding upregulates HMGCS2 expression and inhibits HCC tumor growth, while a reverse correlation between tumor size and HMGCS2 expression was observed. We found that HCC cells with HMGCS2 downregulation possess altered lipid metabolism that increases fatty acid, triglyceride, and cholesterol synthesis. Under KD feeding, a higher tumor growth rate was observed in HMGCS2 knockdown tumors, which had increased lipid synthesis-related marker expression and a positive correlation between lipid quantity and tumor weight. In conclusion, these results demonstrate that the downregulation of HMGCS2 attenuates the protective effect of the KD by shifting ketone production to enhance de novo lipogenesis in HCC. Our study elucidates a new molecular mechanism underlying the crosstalk between HMGCS2 expression and the KD in cancer treatment, which provides more information for precision medicine in developing personalized treatment strategies.

19.
Molecules ; 25(12)2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32575795

RESUMO

Hepatocellular carcinoma (HCC) is a common cause of cancer death worldwide. Sorafenib, a multikinase inhibitor, is the first-line drug approved by the Food and Drug Administration (FDA) for the treatment of patients with advanced HCC. However, most patients who continuously receive sorafenib may acquire resistance to this drug. Therefore, it is important to develop a new compound to treat liver cancer and sorafenib-resistant liver cancer. Barbituric acid derivatives have been used as antiasthmatic drugs in the clinic. We previously reported that a novel barbituric acid derivative inhibited carbon tetrachloride-induced liver fibrosis in mice, but its effects on liver cancer remain unknown. Thus, the purpose of this study was to investigate the antitumor effect of barbituric acid derivatives on HCC cells and sorafenib-resistant HCC cells (HCC-SRs). Our findings reveal that one of the barbituric acid derivatives, BA-5, significantly inhibited HCC and HCC-SR cell viability in a dose- and time-dependent manner. Therefore, compound BA-5 was selected for further experiments. Western blot data revealed that BA-5 treatment decreased the phosphorylation of AKT/p70s6k without affecting the MAPK pathway and increased cleaved PARP and cleaved caspase-7 in both HCC and HCC-SR cells. Since epithelial-mesenchymal transition plays a significant role in regulating cancer invasion and migration, we used the wound healing assay to evaluate the antimigratory effect of compound BA-5. The results showed that BA-5 treatment inhibited HCC and HCC-SR cell migration and reduced Vimentin protein expression. These results were confirmed by microarray analysis showing that BA-5 treatment influenced cancer cell motility and growth-related pathways. In the xenograft mouse model experiment, BA-5 administration significantly inhibited HCC cancer cell growth in mice. Furthermore, the combination of BA-5 with a low dose of regorafenib synergistically inhibited HCC-SR cell proliferation. In conclusion, our study showed that the barbituric acid derivative BA-5 is a new candidate for HCC and sorafenib-resistant HCC therapy.


Assuntos
Antineoplásicos/farmacologia , Barbitúricos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Barbitúricos/administração & dosagem , Barbitúricos/química , Carcinoma Hepatocelular/patologia , Caspase 7/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Perfilação da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Compostos de Fenilureia/administração & dosagem , Poli(ADP-Ribose) Polimerase-1/metabolismo , Piridinas/administração & dosagem , Vimentina/metabolismo , Cicatrização/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Cancers (Basel) ; 12(6)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32570749

RESUMO

Some antihistamines have exhibited significant antitumor activity alone or in combination with other therapies in in vitro and clinical studies. However, the underlying mechanisms of how antihistamines inhibit hepatocellular carcinoma proliferation are still unknown. We first screened the antiproliferation activity of 12 benzocycloheptene structural-analogue drugs, and results showed that deptropine was the most potent inhibitor of both Hep3B and HepG2 human hepatoma cells. Deptropine significantly increased light chain 3B-II (LC3B-II) expression but did not induce sequestosome 1 (SQSTM1/p62) degradation in either cell line. Interestingly, other autophagy-related proteins, such as autophagy-related 7 (ATG7), vacuolar protein sorting 34 (VPS34), phosphorylated adenosine 5'-monophosphate-activated protein kinase (AMPK), and phosphorylated protein kinase B (PKB, also known as Akt), exhibited no significant change in either deptropine-treated cell line. Deptropine also inhibited the processing of cathepsin L from its precursor form to its mature form. Immunofluorescence microscopy showed an increase of autophagosomes in deptropine-treated cells, but deptropine blocked the fusion between autophagosomes and lysosomes. In a xenograft nude mice model, 2.5 mg/kg deptropine showed a great inhibitory effect on Hep3B tumor growth. These results suggest that deptropine can induce in vitro and in vivo hepatoma cell death, and the underlying mechanisms might be mediated through inhibiting autophagy by blocking autophagosome-lysosome fusion.

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