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1.
Anticancer Res ; 44(7): 2909-2919, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38925848

RESUMO

BACKGROUND/AIM: NUAK family kinase 2 (NUAK2) is a promising target for cancer therapeutics due to its reported role in protein phosphorylation, a critical process in cancer cell survival, proliferation, invasion, and senescence. This study aimed to identify novel inhibitors that disrupt NUAK2 activity. We have already identified two KRICT Hippo kinase inhibitor (KHKI) compounds, such as KHKI-01128 and KHKI-01215. Our aim was to evaluate the impact of KHKI-01128 and KHKI-01215 on NUAK2 activity and elucidate its mechanism in colorectal cancer cells. MATERIALS AND METHODS: To evaluate anticancer properties of these inhibitors, four in vitro assays in the SW480 cell line (time-resolved fluorescence resonance energy transfer assay, KINOMEscan kinase profiling, viability, and apoptosis assays) and two pharmacological mechanism analyses (Gene Set Enrichment Analysis and western blotting) were performed. RESULTS: KHKI-01128 and KHKI-01215 exhibited potent inhibitory activity against NUAK2 (half-maximal inhibitory concentration=0.024±0.015 µM and 0.052±0.011 µM, respectively). These inhibitors suppressed cell proliferation, with half-maximal inhibitory concentrations of 1.26±0.17 µM and 3.16±0.30 µM, respectively, and induced apoptosis of SW480 cells. Gene Set Enrichment Analysis revealed negative enrichment scores of -0.84 for KHKI-01128 (false-discovery rate=0.70) and 1.37 for KHKI-01215 (false-discovery rate=0.18), indicating that both effectively suppressed the expression of YES1-associated transcriptional regulator (YAP) target genes. CONCLUSION: These results suggest that KHKI-01128 and KHKI-01215 are potent NUAK2 inhibitors with promising potential for pharmaceutical applications.


Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Neoplasias Colorretais , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Proteínas Quinases/metabolismo
2.
Korean J Physiol Pharmacol ; 28(1): 83-91, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38154967

RESUMO

Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor activated under hypoxic conditions, and it plays a crucial role in cellular stress regulation. While HIF-1α activity is essential in normal tissues, its presence in the tumor microenvironment represents a significant risk factor as it can induce angiogenesis and confer resistance to anti-cancer drugs, thereby contributing to poor prognoses. Typically, HIF-1α undergoes rapid degradation in normoxic conditions via oxygen-dependent degradation mechanisms. However, certain cancer cells can express HIF-1α even under normoxia. In this study, we observed an inclination toward increased normoxic HIF-1α expression in cancer cell lines exhibiting increased HDAC6 expression, which prompted the hypothesis that HDAC6 may modulate HIF-1α stability in normoxic conditions. To prove this hypothesis, several cancer cells with relatively higher HIF-1α levels under normoxic conditions were treated with ACY-241, a selective HDAC6 inhibitor, and small interfering RNAs for HDAC6 knockdown. Our data revealed a significant reduction in HIF-1α expression upon HDAC6 inhibition. Moreover, the downregulation of HIF-1α under normoxic conditions decreased zinc finger E-box-binding homeobox 1 expression and increased E-cadherin levels in lung cancer H1975 cells, consequently suppressing cell invasion and migration. ACY-241 treatment also demonstrated an inhibitory effect on cell invasion and migration by reducing HIF-1α level. This study confirms that HDAC6 knockdown and ACY-241 treatment effectively decrease HIF-1α expression under normoxia, thereby suppressing the epithelial-mesenchymal transition. These findings highlight the potential of selective HDAC6 inhibition as an innovative therapeutic strategy for lung cancer.

3.
Materials (Basel) ; 15(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36556714

RESUMO

High-Mn lightweight steel, Fe-0.9C-29Mn-8Al, was manufactured using steelmaking, ingot-making, forging, and rolling processes. After the final rolling process, a typical austenite single phase was observed on all sides of the thick plate. The microstructural changes after annealing and aging heat-treatments were observed, using optical and transmission electron microscopy. The annealed coupon exhibited a typical austenite single phase, including annealing twins in several grains; the average grain size was 153 µm. After aging heat treatment, κ-carbide was observed within the grains and on the grain boundaries. Additionally, the effect of aging heat treatment on the mechanical properties was analyzed, using a tensile test. The fine κ-carbide that precipitated within the grains in the aged coupon improved the 0.2% offset yield and the tensile stresses, as compared to the as-annealed coupon. To estimate the applicability of high-Mn lightweight steel for low-pressure (LP) steam turbine blades, a low-cycle fatigue (LCF) test was carried out at room temperature. At a total strain amplitude of 0.5 to 1.2%, the LCF life of high-Mn lightweight steel was approximately three times that of 12% Cr steel, which is used in commercial LP steam turbine blades. The LCF behavior of high-Mn lightweight steel followed the Coffin-Manson equation. The LCF life enhancement in the high-Mn lightweight steel results from the planar dislocation gliding behavior.

4.
Clin Hemorheol Microcirc ; 80(1): 17-24, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32116240

RESUMO

BACKGROUND: Platelet function analysis is crucial in assessing the hemostatic status to evaluate congenital and acquired platelet function defects. The Anysis-200 analyzer is a new automated lab-on-a-chip-based platelet function analyzer. OBJECTIVE: We aimed to evaluate a new platelet function analyzing system, the Anysis-200 in comparison to the Platelet Function Analyzer (PFA)-200 in cardiac patients. METHODS: Citrated blood was collected from 174 patients who visited the Department of Cardiology. The Anysis-200 consists of two kits, the microchips with collagen and epinephrine-coated membrane (C/EPI) or adenosine diphosphate-coated membrane (C/ADP). Platelet clogging in the Anysis-200 is measured by the blood migration distance obtained by a camera, which is compatible with the closure time in the PFA-200. We performed Anysis-200 and PFA-200 analyzers simultaneously and compared the results. RESULTS: The sensitivity and specificity of the Anysis-200 C/EPI kit in comparison to the PFA-200 C/EPI kit were 63.41% and 91.43%, respectively. Regarding the C/ADP kit, the sensitivity and specificity of the Anysis-200 were 58.97% and 74.29%, respectively. The agreement rate between the Anysis-200 and PFA-200 for C/EPI was 83.35% and 70.14% for C/ADP. CONCLUSIONS: The Anysis-200, which applies a novel method to detect platelet clogging, has shown moderate to fair agreement with the PFA-200. This test is potentially useful for screening cardiac patients with an abnormal platelet function.


Assuntos
Hemostasia , Testes de Função Plaquetária , Difosfato de Adenosina , Plaquetas , Humanos , Agregação Plaquetária
5.
Semin Thorac Cardiovasc Surg ; 34(2): 537-546, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33713828

RESUMO

Enlarged left atrium (LA) is a risk factor for ablation failure after atrial fibrillation (AF) surgery. It predisposes patients to thromboembolic events, even in successful ablation; therefore, concomitant resection of the LA wall during surgical ablation was introduced. This study examined the clinical impacts of LA reduction in patients undergoing concomitant ablation for AF. This study enrolled 1484 patients with enlarged LA (≥50 mm) who underwent surgical AF ablation during major cardiac surgery between January 2001 and August 2018. Among them, 876 (59%) patients underwent concomitant LA reduction (Reduction group), whereas in the remaining 608 (41%), the LA wall was unresected (Preservation group). The primary outcome of interest was overall stroke. The secondary outcomes were overall mortality, late recurrence of AF, early postoperative complications and postoperative echocardiographic parameters. Outcomes were compared after adjusting baseline characteristics with inverse probability of treatment weighting (IPTW) using propensity score. The median follow-up was 60.1 months. After IPTW adjustment, long-term mortality (P = 0.250) and AF-free rates (P = 0.196) did not significantly differ between groups. However, the Reduction group showed a decreased risk of stroke (hazard ratio 0.54; 95% confidence interval 0.32-0.90; P = 0.018). Early postoperative complications rate such as mortality or reoperation for bleeding, was not significantly different between the 2 groups. The Reduction group showed smaller LA diameter (50.6 ± 8.0 mm vs 53.6 ± 8.9 mm; P < 0.001) on follow-up echocardiography. LA reduction effectively decreased LA size and appeared to decrease the stroke risk in patients with enlarged LA undergoing ablation for AF.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Acidente Vascular Cerebral , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Humanos , Complicações Pós-Operatórias/cirurgia , Recidiva , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
6.
Biosens Bioelectron ; 199: 113872, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902643

RESUMO

The exosome is considered a useful biomarker for the early diagnosis of cancer. However, pretreatment of samples used in diagnosis is time-consuming. Herein, we fabricated a capacitance-based electrical biosensor that requires no pretreatment of the sample; it is composed of a DNA aptamer/molybdenum disulfide (MoS2) heterolayer on an interdigitated micro-gap electrode (IDMGE)/printed circuit board (PCB) system for detecting exosomes in an undiluted serum sample. The DNA aptamer detects the CD63 protein on the exosome as the biomarker, while the MoS2 nanoparticle enhances electrical sensitivity. In this study, for the first time, the IDMGE system was used to amplify the electrical signal efficiently for exosome detection. The IDMGE amplifies the capacitance signal as the gap between electrodes decreases, making it easy to detect the target by utilizing the heightened sensitivity. Moreover, it is possible to immobilize a bio-probe more efficiently than with an electrical sensitivity-enhancing electrode with the same area. The thiol-modified (SH-) CD63 DNA aptamer was introduced as the bio-probe that selectively binds to the CD63 protein on the exosome surface. The capacitance signal from the IDMGE electrical sensor increased linearly with the increase in the concentration of exosomes in human serum expressed on a logarithmic scale, the detection limit being 2192.6 exosomes/mL. The proposed biosensor can detect exosomes in undiluted human serum with high selectivity and sensitivity. A blind test was also carried out to test the reliability of the biosensor. The capacitance-based electrical biosensor thus offers a new platform for cancer diagnosis in the future.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Exossomos , Capacitância Elétrica , Humanos , Reprodutibilidade dos Testes
7.
Arch Pharm Res ; 44(12): 1062-1075, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34761352

RESUMO

Histone deacetylase 6 (HDAC6) is a promising target for cancer treatment because it regulates cell mobility, protein trafficking, cell growth, apoptosis, and metastasis. However, the mechanism of HDAC6-induced anticancer drug resistance is unclear. In this study, we evaluated the anticancer effect of ACY-241, an HDAC6-selective inhibitor, on erlotinib-resistant pancreatic cancer cells that overexpress HDAC6. Our data revealed that ACY-241 hyperacetylated the HDAC6 substrate, α-tubulin, leading to a significant reduction in cell viability of erlotinib-resistant pancreatic cells, BxPC3-ER and HPAC-ER. Notably, a synergistic anticancer effect was observed in cells that received combined treatment with ACY-241 and erlotinib. Combined treatment effectively induced autophagy and inhibited autophagy through siLC3B, and siATG5 alleviated ACY-241-mediated cell death, as reflected by the recovery of PARP cleavage and apoptosis rates. In addition, combined ACY-241 and erlotinib treatment induced autophagy and subsequently, cell death by reducing AKT-mTOR activity and increasing phospho-AMPK signaling. Therefore, HDAC6 may be involved in the suppression of autophagy and acquisition of resistance to erlotinib in ER pancreatic cancer cells. ACY-241 to overcome erlotinib resistance could be an effective therapeutic strategy against pancreatic cancer.


Assuntos
Cloridrato de Erlotinib , Inibidores de Histona Desacetilases , Neoplasias Pancreáticas , Pirimidinas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Cloridrato de Erlotinib/farmacologia , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos
8.
Sci Rep ; 11(1): 17130, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429501

RESUMO

The role of matrix metalloproteinase-2 (MMP-2) in tumor cell migration has been widely studied, however, the characteristics and effects of MMP-2 in clinical sample of metastatic colorectal cancer (CRC) remain poorly understood. Here, in order to unveil the perturbed proteomic signal during MMP-2 induced cancer progression, we analyzed plasma proteome of CRC patients according to disease progression, HCT116 cancer secretome upon MMP-2 knockdown, and publicly available CRC tissue proteome data. Collectively, the integrative analysis of multi-layered proteomes revealed that a protein cluster containing EMT (Epithelial-to-Mesenchymal Transition)-associated proteins such as CD9-integrin as well as MMP-2. The proteins of the cluster were regulated by MMP-2 perturbation and exhibited significantly increased expressions in tissue and plasma as disease progressed from TNM (Tumor, Node, and Metastasis) stage I to II. Furthermore, we also identified a plausible association between MMP-2 up-regulation and activation of focal adhesion kinase signaling in the proteogenomic analysis of CRC patient tissues. Based on these comparative and integrative analyses, we suggest that the high invasiveness in the metastatic CRC resulted from increased secretion of MMP-2 and CD9-integrin complex mediated by FAK signaling activation.


Assuntos
Neoplasias Colorretais/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Células Cultivadas , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Quinase 1 de Adesão Focal/genética , Células HCT116 , Humanos , Metaloproteinase 2 da Matriz/genética , Metástase Neoplásica , Proteoma/genética , Proteoma/metabolismo , Transdução de Sinais , Tetraspanina 29/genética , Tetraspanina 29/metabolismo
9.
Sci Rep ; 11(1): 14468, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262073

RESUMO

We investigated the effect of κ-carbide precipitates on the strain hardening behavior of aged Fe-Mn-Al-C alloys by microstructure analysis. The κ-carbides-strengthened Fe-Mn-Al-C alloys exhibited a superior strength-ductility balance enabled by the recovery of the strain hardening rate. To understand the relation between the κ-carbides and strain hardening recovery, dislocation gliding in the aged alloys during plastic deformation was analyzed through in situ tensile transmission electron microscopy (TEM). The in situ TEM results confirmed the particle shearing mechanism leads to planar dislocation gliding. During deformation of the 100 h-aged alloy, some gliding dislocations were strongly pinned by the large κ-carbide blocks and were prone to cross-slip, leading to the activation of multiple slip systems. The abrupt decline in the dislocation mean free path was attributed to the activation of multiple slip systems, resulting in the rapid saturation of the strain hardening recovery. It is concluded that the planar dislocation glide and sequential activation of slip systems are key to induce strain hardening recovery in polycrystalline metals. Thus, if a microstructure is designed such that dislocations glide in a planar manner, the strain hardening recovery could be utilized to obtain enhanced mechanical properties of the material.

10.
Medicina (Kaunas) ; 57(6)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208279

RESUMO

The aim of the present study was to report two cases of refractory dry eye syndrome (DES) after transconjunctival excision of the palpebral lobe of the lacrimal gland. A 25-year-old female patient with a chief complaint of a palpable mass in both upper eyelids visited our medical center. Preoperative orbital computer tomography showed high-attenuation lesions in both lacrimal glands. Incisional biopsy of the lacrimal gland palpebral lobe via transconjunctival incision was performed in January 2019. At 1 month after the biopsy, a lack of tears and persistent corneal erosions were found in both eyes. Artificial tears, punctal occlusion, autologous serum eye drops, and therapeutic contact lenses were applied in an attempt to control the dry eye symptoms. The patient continues to suffer from intractable DES at 2.5 years after the procedure. The second case involved a 52-year-old female patient who visited our medical center with a chief complaint of a palpable mass in both upper eyelids. Bilateral orbital tumors were diagnosed with preoperative magnetic resonance imaging. An incisional biopsy of the lacrimal gland was performed. Immunoglobulin G4-related dacryoadenitis was confirmed through lacrimal palpebral lobe incisional biopsy. Intractable DES and corneal erosion of her left eye persisted thereafter. A transconjunctival incision is an effective approach for minimizing postoperative scars and is suitable for the biopsy of tumors that are visible through the conjunctiva. After a biopsy of the palpebral lobe of the main lacrimal glands, the secretion of reflex tears decreases due to damage to the secreting ducts of the main lacrimal glands. However, total tear secretion can be maintained by basal tear secretion from the accessory lacrimal glands. In this report, we describe two cases of refractory DES due to decreased total tear secretion, although only the palpebral lobes of the main lacrimal glands were biopsied.


Assuntos
Síndromes do Olho Seco , Aparelho Lacrimal , Adulto , Túnica Conjuntiva/cirurgia , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/cirurgia , Pálpebras , Feminino , Humanos , Aparelho Lacrimal/diagnóstico por imagem , Aparelho Lacrimal/cirurgia , Pessoa de Meia-Idade , Lágrimas
11.
Korean J Intern Med ; 36(2): 292-304, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32241083

RESUMO

BACKGROUND/AIMS: Chronic hepatitis C (CHC) treatment has dramatically improved since direct-acting antiviral (DAA) therapy was introduced. However, the use of DAA therapy in CHC patients with hepatocellular carcinoma (HCC) remains controversial. We investigated the DAA treatment response in CHC patients with HCC. METHODS: We retrospectively analyzed CHC patients treated with DAA from 2016 to 2018. Patients were divided into two groups based on their HCC-history before DAA therapy. Baseline characteristics, sustained virologic response at 12 weeks (SVR 12), and HCC recurrence after DAA therapy were evaluated. We also used propensity score matching (PSM) in a 2:1 ratio to reduce confounding variables. RESULTS: A total of 192 patients were enrolled; 78.1% were treatment-naïve, and 34.9% had liver cirrhosis (LC). Among these patients, 168 did not have HCC, and 24 had HCC. The HCC group was older (57.0 years vs. 72.0 years, p < 0.001), had a higher incidence of LC (26.2% vs. 95.8%, p < 0.001), fibrosis-4 index (2.6 vs. 9.2, p < 0.001), liver stiffness measurement (7.0 kPa vs. 17.4 kPa, p = 0.012), and α-fetoprotein (4.4 ng/mL vs. 8.2 ng/mL, p ≤ 0.001). The SVR 12 rate was 97.0% in the non- HCC group and 91.7% in the HCC group (p = 0.213). HCC recurrence was observed in 14 patients (58.3%) in the HCC group. CONCLUSION: DAA treatment efficacy in CHC patients with or those without HCC were not significantly different, and HCC recurrence was relatively common.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Neoplasias Hepáticas , Antivirais/efeitos adversos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/etiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Recidiva Local de Neoplasia , Estudos Retrospectivos
12.
PLoS One ; 15(10): e0240533, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33091036

RESUMO

Ginsenoside Rg3 (Rg3) has been studied in several cancer models and is suggested to act through various pharmacological effects. We investigated the anticancer properties of Rg3 through myeloid-derived suppressor cell (MDSC) modulation in FM3A mouse mammary carcinoma cells. The effects of Rg3 on MDSCs and consequent changes in cancer stem-like cells (CSCs) and epithelial-mesenchymal transition (EMT) were evaluated by diverse methods. MDSCs promoted cancer by enhancing breast cancer stemness and promoting EMT. Rg3 at a dose without obvious cytotoxicity downregulated MDSCs and repressed MDSC-induced cancer stemness and EMT. Mechanistic investigations suggested that these inhibitory effects of Rg3 on MDSCs and corresponding cancer progression depend upon suppression of the STAT3-dependent pathway, tumor-derived cytokines, and the NOTCH signaling pathway. In a mouse model, MDSCs accelerated tumor progression, and Rg3 delayed tumor growth, which is consistent with the results of in vitro experiments. These results indicated that Rg3 could effectively inhibit the progression of breast cancer. The anticancer effect of Rg3 might be partially due to its downregulation of MDSCs and consequent repression of cancer stemness and EMT in breast cancer. Hence, we suggest the regulation of MDSCs through Rg3 treatment as an effective therapeutic strategy for breast cancer patients.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Ginsenosídeos/farmacologia , Células Supressoras Mieloides/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/farmacologia , Carcinoma/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Camundongos , Camundongos Endogâmicos C3H , Células Supressoras Mieloides/patologia
13.
Materials (Basel) ; 13(3)2020 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-32050427

RESUMO

Small objects of an alloy tool steel were built by selective laser melting at different scan speeds, and their microstructures were analyzed using electron backscatter diffraction (EBSD). To present an explicit correlation with the local thermal cycles in the objects, prior austenite grains were reconstructed using the EBSD mapping data. Extensive growth of austenitic grains after solidification could be detected by the disagreement between the networks of carbides and austenite grain boundaries. A rapid laser scan at 2000 mm/s led to less growth, but retained a larger amount of austenite than a slow one at 50 mm/s. The rapid scan also exhibited definite evolution of Goss-type textures in austenite, which could be attributed to the growth of austenitic grains under a steep temperature gradient. The local variations in the microstructures and the textures enabled us to speculate the locally different thermal cycles determined by the different process conditions, that is, scan speeds.

14.
Sci Rep ; 9(1): 15171, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645600

RESUMO

To gain the fundamental understanding of deformation mechanisms in an aluminum-containing austenitic high-Mn steel (Fe-32Mn-8.9Al-0.78 C (wt.%)), in-situ straining transmission electron microscopy (TEM) analysis is conducted. The in-situ observation during the deformation demonstrates that the plastic deformation is accommodated by the pronounced planar dislocation gliding followed by the formation of slip bands (SBs) and highly dense dislocation walls (HDDWs). Experimental evidences of the glide plane softening can be obtained from the interaction between the gliding perfect dislocations and the L'12 ordered precipitates in the austenite matrix. Furthermore, the observation of the localized cross-slip of dislocations at the slip band intersections enables to understand why slip bands are extensively developed without mutual obstructions between the slip bands. The enhanced strain hardening rate of the aluminum-containing austenitic high-Mn steels can be attributed to the pronounced planar dislocation glides followed by formation of extensive slip band which prevent premature failure by suppressing strain localization.

15.
Korean J Gastroenterol ; 73(3): 167-176, 2019 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-31013560

RESUMO

Background/Aims: Surgical resection or ablation is recommended for the treatment of early hepatocellular carcinoma (HCC), whereas transarterial chemoembolization (TACE) is frequently used in early HCC ineligible for curative resection. We evaluated the clinical effects and safety of radiofrequency ablation (RFA) shortly after TACE in patients with Barcelona clinic liver cancer (BCLC) stage A HCC. Methods: Sixty-seven BCLC stage A HCC patients who failed to achieve complete response to TACE as either a first line treatment and who subsequently received RFA at the Konkuk University Medical Center from January 2005 to December 2017 were included. Evaluation indices included treatment response, overall survival rate, recurrence-free survival, prognostic factors, and procedure-related complications. Results: Median follow-up was 46.9 months. Fifty-four (80.6%) patients were of Child-Pugh class A, and 13 (19.4%) were of class B. Modified UICC stages were I in 10 (14.9%), II in 46 (68.7%), and III in 11 (16.4%) patients. In the 67 study subjects, cumulative recurrence-free survival rates were 86.8%, 55.9% and 29.7% at 1, 3, and 5 years, respectively, and overall survival rates were 100%, 93.4%, and 83.5% at 1, 3, and 5 years, respectively. Tumor size significantly predicted recurrence. No treatment-related death occurred. Conclusions: Combination of RFA was an efficient and safe treatment for BCLC stage A HCC patients that failed to achieve complete response to initial TACE. We suggest TACE plus RFA be considered as a curative option for early HCC patients ineligible for curative resection of RFA.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Ablação por Radiofrequência , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
16.
Korean J Gastroenterol ; 72(4): 197-204, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30419644

RESUMO

BACKGROUND/AIMS: Direct-acting antiviral (DAA) therapy has been shown to achieve a high rate of sustained virologic response (SVR) and favorable outcomes in chronic hepatitis C (CHC) patients. We investigated the virologic response and its clinical impact in CHC patients. METHODS: CHC patients with compensated liver function treated with DAAs between 2016 and 2017 were included for retrospective analysis. We analyzed baseline characteristics and virologic and biochemical responses at on-treatment 4 weeks, end of treatment, and post-treatment 12 weeks. Fibrosis was measured as liver stiffness measurement by transient elastography (FibroScan). Adverse events were monitored during the treatment period. RESULTS: A total of 135 patients (61.5% with genotype [GT] 1b and 38.5% with GT 2a) were enrolled 47.4% were male, 79.3% were treatment naive, and 30.4% had cirrhosis. SVR 12 was observed in 97.6% (81/83) in the GT 1b and 98.1% (51/52) in the GT 2a; treatment with daclatasvir+asunaprevir was the most commonly used in GT 1b (55/83), and sofosbuvir+ribavirin was the most commonly used in GT 2a (49/52). The median change of liver stiffness measurement at two time points using the signed rank test was -3.2 kPa in patients who underwent transient elastography before treatment and at SVR 12 (n=25). The most common adverse events were anemia, dyspepsia, and insomnia. One GT 2a patient treated with sofosbuvir+ribavirin stopped the treatment at 8 weeks due to symptomatic bradyarrhythmia; however, he recovered spontaneously and achieved SVR 12. CONCLUSIONS: DAA treatment of chronic hepatitis C genotype 1b and 2a resulted in a high rate of sustained virologic response and improvement of liver fibrosis score.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Adulto , Idoso , Antivirais/efeitos adversos , Esquema de Medicação , Dispepsia/etiologia , Técnicas de Imagem por Elasticidade , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ribavirina/uso terapêutico , Sofosbuvir/uso terapêutico , Resposta Viral Sustentada , Resultado do Tratamento
17.
Ophthalmic Plast Reconstr Surg ; 34(6): 547-551, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29634605

RESUMO

PURPOSE: To determine the relationship between the distribution of adrenergic receptors in the human eyelid and the eyelid elevation after topically instilling 0.5% apraclonidine in blepharoptosis patients. METHODS: A total of 26 blepharoptotic patients (30 eyelids) were included in the experimental study. Marginal reflex distance 1 was measured before and after topical instillation of 0.5% apraclonidine. Eyelids were divided into 2 groups according to the responses to topical 0.5% apraclonidine. Patients who positively responded to apraclonidine were classified as group A and those that negatively responded to it were classified as group B. Müller's muscle was obtained during the blepharoptotic surgery, followed by immunohistochemical staining and scoring. This study was approved by the Institutional Review Board of Kim's Eye Hospital and the study protocol adhered to the tenets of the Declaration of Helsinki. RESULTS: α-1D staining intensity was significantly higher in group A than in B (p < 0.001) and α-2C and ß-1 staining intensities were significantly higher in group B than in A (p < 0.001 and p < 0.05, respectively). The difference in ß-2 staining intensity between groups A and B was not statistically significant. CONCLUSIONS: α-1D adrenoceptor was predominant in patients showing a positive response to topical 0.5% apraclonidine. Because apraclonidine has an α-1 agonistic effect, α-1D adrenoceptor may contribute to apraclonidine's elevating effect in patients with blepharoptosis.


Assuntos
Agonistas alfa-Adrenérgicos/administração & dosagem , Blefaroptose/tratamento farmacológico , Clonidina/análogos & derivados , Pálpebras/metabolismo , Receptores Adrenérgicos/metabolismo , Adolescente , Agonistas alfa-Adrenérgicos/efeitos adversos , Adulto , Idoso , Criança , Clonidina/administração & dosagem , Clonidina/efeitos adversos , Pálpebras/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
Br J Ophthalmol ; 102(3): 407-414, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29101123

RESUMO

AIM: To examine the role of microRNA-146a (miR-146a) in the regulation of fibrosis in an in vitro model of Graves' orbitopathy (GO). METHODS: Orbital fat/connective tissues were harvested from patients with GO and non-GO for primary orbital fibroblast cultures. The effects of transforming growth factor-ß (TGF-ß), a potent cytokine that promotes fibrosis, on miR-146a expression were analysed in GO and non-GO orbital fibroblasts using quantitative real-time PCR. The effects of overexpressed miR-146a on TGF-ß-induced fibrotic markers were examined in GO orbital fibroblasts by western blot analysis. Expression ofSma and Mad related family (Smad) 4/tumour necrosis factor receptor-associated factor 6 (TRAF6) after transfection of miR-146a mimics or inhibitors were examined. RESULTS: TGF-ß induced an increase in miR-146a expression in orbital fibroblasts from patients with GO in a time-dependent and concentration-dependent manner. miR-146a mimics further decreased the production of TGF-ß-induced fibronectin, collagen Iα and α-smooth muscle actin protein. The Smad4 and TRAF6 protein levels were significantly decreased by miR-146a mimics, compared with control mimics, and significantly increased on inhibition of miR-146a production compared with a control. CONCLUSIONS: miR-146a plays a role as a negative regulator in the production of TGF-ß-induced fibrotic markers. Thus, miR-146a may be involved in the regulation of fibrosis in orbital fibroblasts from patients with GO.


Assuntos
Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Oftalmopatia de Graves/genética , MicroRNAs/genética , Órbita/patologia , Actinas/metabolismo , Western Blotting , Células Cultivadas , Colágeno Tipo I/metabolismo , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Fibronectinas/metabolismo , Fibrose , Oftalmopatia de Graves/metabolismo , Oftalmopatia de Graves/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Fosforilação , Reação em Cadeia da Polimerase em Tempo Real , Proteína Smad4/genética , Fator 6 Associado a Receptor de TNF/genética , Fatores de Tempo , Transfecção , Fator de Crescimento Transformador beta/farmacologia
19.
Anal Chem ; 89(18): 9830-9835, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28806509

RESUMO

We have developed two-photon (TP) pH-sensitive probes (BH-2 and BHEt-1) that exhibit absorption and emission maxima at 370 and 466 nm, and TP absorption cross-section values of 51 and 61 GM (1 GM = 10-50cm4s/photon), respectively, at 750 nm and pH 3.0 in a universal buffer (0.1 M citric acid, 0.1 M KH2PO4, 0.1 M Na2B4O7, 0.1 M Tris, 0.1 M KCl)/1,4-dioxane (7/3) solution. The TPM images of CCD-18co (a normal colon cell line) and HCT116 cells (a colon cancer cell line) labeled with BH-2 were too dim to be distinguished. When the same cells were labeled with BHEt-1, however, the TPM image of the HCT116 cells was much brighter than that of CCD-18co cells, and the relative proportion of the acidic vesicles (Pacid) of the former was 5-fold larger than that of latter. BHEt-1 could also differentiate HepG2 cells (a human liver cancer cell line) from LX-2 cells (a human hepatic stellate cell line) with a 6-fold larger Pacid value. Human colon cancer tissues labeled with BHEt-1 showed similar results, demonstrating much brighter TPM images and 6-fold larger Pacid values compared to normal tissue. These results suggest the potential utility of BHEt-1 for detecting colon cancer in human tissues using TPM.


Assuntos
Neoplasias do Colo/diagnóstico por imagem , Corantes Fluorescentes/química , Fótons , Linhagem Celular , Corantes Fluorescentes/síntese química , Células HCT116 , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Microscopia de Fluorescência por Excitação Multifotônica , Estrutura Molecular
20.
Nat Immunol ; 17(11): 1252-1262, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27595231

RESUMO

The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.


Assuntos
Aminoacil-tRNA Sintetases/metabolismo , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno/imunologia , Viroses/imunologia , Viroses/metabolismo , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/genética , Animais , Antivirais/farmacologia , Modelos Animais de Doenças , Imunidade Inata , Camundongos , Camundongos Knockout , Peptídeos/farmacologia , Fosforilação , Ligação Proteica , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/metabolismo , Infecções por Vírus de RNA/virologia , Vírus de RNA/efeitos dos fármacos , Vírus de RNA/imunologia , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Ubiquitinação , Viroses/virologia , Replicação Viral
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