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1.
Biochem Biophys Rep ; 38: 101690, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38571555

RESUMEN

Electric fields (EF) play an essential role in cancer cell migration. Numerous cancer cell types exhibit electrotaxis under direct current electric fields (dcEF) of physiological electric field strength (EFs). This study investigated the effects of doxycycline on the electrotactic responses of U87 cells. After EF stimulation, U87 cells migrated toward the cathode, whereas doxycycline-treated U87 cells exhibited enhanced cell mobility but hindered cathodal migration. We further investigated the expression of the metastasis-correlated proteins matrix metallopeptidase-2 (MMP-2) and MMP-9 in U87 cells. The levels of MMP-2 in the cells were not altered under EF or doxycycline stimulation. In contrast, the EF stimulation greatly enhanced the levels of MMP-9 and then repressed in doxycycline-cotreated cells, accompanied by reduced cathodal migration. Our results demonstrated that an antibiotic at a non-toxic concentration could suppress the enhanced cell migration accelerated by EF of physiological strength. This finding may be applied as an anti-metastatic treatment for cancers.

2.
RSC Adv ; 14(6): 3808-3819, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38274165

RESUMEN

Glutathione (GSH) is a major antioxidant in organisms. An alteration in GSH concentration has been implicated in a number of pathological conditions. Therefore, GSH sensing has become a critical issue. In this study, a disposable strip used for tyrosinase-modified electrochemical testing was fabricated for the detection of GSH levels in vivo. The system is based on tyrosinase as a biorecognition element and a screen-printed carbon electrode (SPCE) as an amperometric transducer. On the tyrosinase-SPCE strips, the oxidation reaction from catechol to o-quinone was catalyzed by tyrosinase. The tyrosinase-SPCE strips were modified with gold nanoparticles (AuNPs). In the presence of AuNPs of 25 nm diameter, the cathodic peak current of cyclic voltammetry (CV) was significantly enhanced by 5.2 fold. Under optimized conditions (250 µM catechol, 50 mM phosphate buffer, and pH 6.5), the linear response of the tyrosinase-SPCE strips ranged from 31.25 to 500 µM GSH, with a detection limit of approximately 35 µM (S/N > 3). The tyrosinase-SPCE strips have been used to detect real samples of plasma and tissue homogenates in a mouse experiment. The mice were orally administrated with N-acetylcysteine (NAC) 100 mg kg-1 once a day for 7 days; the plasma GSH significantly enhanced 2.8 fold as compared with saline-treated mice (1123 vs. 480 µM µg-1 protein). NAC administration also could alleviate the adverse effect of GSH reduction in the mice treated with doxorubicin.

3.
Hypertens Res ; 46(6): 1375-1384, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36759661

RESUMEN

Aldosterone excess is present in obesity and is associated with involvement in the pathogenesis of obesity. We evaluate the impact of body obesity as measured by body composition monitor (BCM) on clinical outcomes in patients with unilateral primary aldosteronism (uPA) after adrenalectomy. The BCM device was used to assess body composition before and after adrenalectomy. We used fat mass (FM) and body mass index (BMI) to classify obesity and divided obesity into three groups: clinical overweight (BMI (kg/m2) ≥25); normal weight obesity (NWO, FM (%) ≥ 35 for women, >25 for men & BMI < 25); and no obesity (FM < 35 for women, <25 for men & BMI < 25). A total of 130 unilateral PA (uPA) patients received adrenalectomy, and 27 EH patients were identified; uPA patients with hypertension remission were found to have lower FM (p = 0.046), BMI (p < 0.001), and lower prevalence of overweight (p = 0.001). In the logistic regression model, patients with clinical overweight (OR = 2.9, p = 0.007), NWO (OR = 3.04, p = 0.041) and longer HTN duration (years, OR = 1.065, p = 0.013) were at the risk of persistent hypertension after adrenalectomy. Obesity status was strongly associated with persistent hypertension in uPA patients after adrenalectomy. However, patients in the NWO group also carried higher risk of persistent hypertension. Therefore, assessment of pre-obesity and overweight in uPA patients are extremely important, especially in those who have normal BMI.


Asunto(s)
Adrenalectomía , Hiperaldosteronismo , Hipertensión , Hipertensión/etiología , Hiperaldosteronismo/cirugía , Adrenalectomía/efectos adversos , Humanos , Obesidad/complicaciones , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Creatinina/sangre , Renina/sangre , Índice de Masa Corporal
4.
Molecules ; 17(7): 8010-21, 2012 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-22759914

RESUMEN

Recently colorectal cancer rates have increased rapidly in Taiwan. The treatment of colorectal cancer includes surgery, radiation therapy and chemotherapy. Mangosteen (Garcinia mangostana) is a famous Asian tropical fruit. γ-Mangostin is a xanthone derivative isolated from the fruit hull. In previous studies, we found evidence of anti-inflammatory and anti-brain tumor activities in γ-mangostin. In this study, we performed further studies to assess the apoptotic effects of γ-mangostin on colorectal adenocarcinoma cells HT29. γ-Mangostin showed concentration and time-dependent cytotoxic effects on HT29 cells. Microscopic observation under Giemsa staining showed that γ-mangostin induced cellular swelling and the appearance of apoptotic bodies, characteristic of apoptosis in HT29 cells. In addition, flow cytometry analysis showed an increase of hypodiploid cells in γ-mangostin-treated HT29 cells, while enhancement of intracellular peroxide production was detected in the same γ-mangostin-treated cells by DCHDA assay and DiOC6(3) staining. In view of the above results, γ-mangostin has demonstrated anticancer activity and induces apoptosis in HT29 colorectal adenocarcinoma cells. The evidence suggests that γ-mangostin could serve as a micronutrient for colon cancer prevention and is a potential lead compound for the development of anti-colon cancer agents.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias del Colon/patología , Frutas/química , Garcinia mangostana/química , Micronutrientes/farmacología , Xantonas/farmacología , Catalasa/metabolismo , Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Diploidia , Ensayos de Selección de Medicamentos Antitumorales , Células HT29 , Humanos , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Peróxidos/metabolismo , Fitoterapia , Factores de Tiempo , Xantonas/química
5.
J Vis Exp ; (170)2021 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33938879

RESUMEN

Physiological electric fields (EF) play vital roles in cell migration, differentiation, division, and death. This paper describes a microfluidic cell culture system that was used for a long-term cell differentiation study using microscopy. The microfluidic system consists of the following major components: an optically transparent electrotactic chip, a transparent indium-tin-oxide (ITO) heater, a culture media-filling pump, an electrical power supply, a high-frequency power amplifier, an EF multiplexer, a programmable X-Y-Z motorized stage, and an inverted phase-contrast microscope equipped with a digital camera. The microfluidic system is beneficial in simplifying the overall experimental setup and, in turn, the reagent and sample consumption. This work involves the differentiation of neural stem and progenitor cells (NPCs) induced by direct current (DC) pulse stimulation. In the stem cell maintenance medium, the mouse NPCs (mNPCs) differentiated into neurons, astrocytes, and oligodendrocytes after the DC pulse stimulation. The results suggest that simple DC pulse treatment could control the fate of mNPCs and could be used to develop therapeutic strategies for nervous system disorders. The system can be used for cell culture in multiple channels, for long-term EF stimulation, for cell morphological observation, and for automatic time-lapse image acquisition. This microfluidic system not only shortens the required experimental time, but also increases the accuracy of control on the microenvironment.


Asunto(s)
Diferenciación Celular , Animales , Astrocitos/citología , Técnicas de Cultivo de Célula , Electricidad , Dispositivos Laboratorio en un Chip , Ratones , Células-Madre Neurales/citología , Neuronas/citología , Oligodendroglía/citología
6.
Diagnostics (Basel) ; 11(10)2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34679458

RESUMEN

The COVID-19 pandemic is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2020-2021. COVID-19 is becoming one of the most fatal pandemics in history and brings a huge challenge to the global healthcare system. Opportune detection, confinement, and early treatment of infected cases present the first step in combating COVID-19. Diagnosis via viral nucleic acid amplification tests (NAATs) is frequently employed and considered the standard procedure. However, with an increasing urge for point-of-care tests, rapid and cheaper immunoassays are widely utilized, such as lateral flow immunoassay (LFIA), which can be used for rapid, early, and large-scale detection of SARS-CoV-2 infection. In this narrative review, the principle and technique of LFIA applied in COVID-19 antigen and antibody detection are introduced. The diagnostic sensitivity and specificity of the commercial LFIA tests are outlined and compared. Generally, LFIA antigen tests for SARS-CoV-2 are less sensitive than viral NAATs, the "gold standard" for clinical COVID-19 diagnosis. However, antigen tests can be used for rapid and mass testing in high-risk congregate housing to quickly identify people with COVID-19, implementing infection prevention and control measures, thus preventing transmission. LFIA anti-SARS-CoV-2 antibody tests, IgM and/or IgG, known as serology tests, are used for identification if a person has previously been exposed to the virus or vaccine immunization. Notably, advanced techniques, such as LFT-based CRISPR-Cas9 and surface-enhanced Raman spectroscopy (SERS), have added new dimensions to the COVID-19 diagnosis and are also discussed in this review.

7.
J Med Chem ; 64(12): 8053-8075, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34080862

RESUMEN

Starting from our previously described PI3Kγ inhibitors, we describe the exploration of structure-activity relationships that led to the discovery of highly potent dual PI3Kγδ inhibitors. We explored changes in two positions of the molecules, including macrocyclization, but ultimately identified a simpler series with the desired potency profile that had suitable physicochemical properties for inhalation. We were able to demonstrate efficacy in a rat ovalbumin challenge model of allergic asthma and in cells derived from asthmatic patients. The optimized compound, AZD8154, has a long duration of action in the lung and low systemic exposure coupled with high selectivity against off-targets.


Asunto(s)
Asma/tratamiento farmacológico , Fosfatidilinositol 3-Quinasa Clase Ib/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Sulfonamidas/uso terapéutico , Tiazoles/uso terapéutico , Animales , Asma/inducido químicamente , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Cristalografía por Rayos X , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Masculino , Estructura Molecular , Ovalbúmina , Fosfatidilinositol 3-Quinasas/metabolismo , Unión Proteica , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacocinética , Ratas Endogámicas BN , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/metabolismo , Sulfonamidas/farmacocinética , Tiazoles/síntesis química , Tiazoles/metabolismo , Tiazoles/farmacocinética
8.
Bioorg Med Chem ; 18(23): 8374-82, 2010 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-20980155

RESUMEN

Positive modulators at benzodiazepine sites of α2- and α3-containing GABA(A) receptors are believed to be anxiolytic. Negative allosteric modulators of α5-containing GABA(A) receptors enhance cognition. By oocyte two-electrode voltage clamp and subsequent structure-activity relationship studies, we discovered cinnoline and quinoline derivatives that were both positive modulators at α2-/α3-containing GABA(A) receptors and negative modulators at α5-containing GABA(A) receptors. In addition, these compounds showed no functional activity at α1-containing GABA(A) receptors. Such dual functional modulators of GABA(A) receptors might be useful for treating comorbidity of anxiety and cognitive impairments in neurological and psychiatric illnesses.


Asunto(s)
Receptores de GABA-A/química , Regulación Alostérica , Benzodiazepinas/química , Compuestos Heterocíclicos con 2 Anillos/síntesis química , Compuestos Heterocíclicos con 2 Anillos/química , Compuestos Heterocíclicos con 2 Anillos/farmacología , Técnicas de Placa-Clamp , Teoría Cuántica , Quinolinas/síntesis química , Quinolinas/química , Quinolinas/farmacología , Receptores de GABA-A/metabolismo , Relación Estructura-Actividad
9.
Molecules ; 15(12): 8953-66, 2010 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-21139533

RESUMEN

Gliomas are a common type of primary brain tumor with glioblastoma multiforme accounting for the majority of human brain tumors. In this paper, high grade human malignant glioblastomas (MGs) including U87 MG and GBM 8401 were used to evaluate the antitumor effects of γ-mangostin, a xanthone derivative isolated and purified from the hull of the tropical fruit Garcinia mangostana. The γ-mangostin showed potent antiproliferative activity toward MGs in dose- and time-dependent manners. In addition, flow cytometric analysis of cell morphology in the apoptotic cells revealed an increase in hypodiploid cells in γ-mangostin treated U87 MG and GBM 8401 cells, while significant enhancement of intracellular peroxide production was detected in the same γ-mangostin treated cells by DCHDA assay and DiOC(6)(3) stain. g-Mangostin induced apoptosis, which in turn mediates cytotoxicity in human MG cells was prevented by the addition of catalase. Naturally derived medicines and herbal therapies are drawing increasing attention in regard to the treatment of many health issues, and this includes the testing of new phytochemicals or nutrients for brain tumor patients. This has led to γ-mangostin being identified as a potential leading compound for the development of an anti-brain tumor agent.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Garcinia mangostana/química , Glioma/tratamiento farmacológico , Xantonas/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales/métodos , Frutas , Glioma/metabolismo , Humanos , Fitoterapia/métodos , Factores de Tiempo , Xantonas/química , Xantonas/aislamiento & purificación
10.
Sci Rep ; 9(1): 8094, 2019 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-31147570

RESUMEN

Adenocarcinoma, large cell carcinoma and squamous cell carcinoma are the most commonly diagnosed subtypes of non-small cell lung cancers (NSCLC). Numerous lung cancer cell types have exhibited electrotaxis under direct current electric fields (dcEF). Physiological electric fields (EF) play key roles in cancer cell migration. In this study, we investigated electrotaxis of NSCLC cells, including human large cell lung carcinoma NCI-H460 and human lung squamous cell carcinoma NCI-H520 cells. Non-cancerous MRC-5 lung fibroblasts were included as a control. After dcEF stimulation, NCI-H460 and NCI-H520 cells, which both exhibit epithelial-like morphology, migrated towards the cathode, while MRC-5 cells, which have fibroblast-like morphology, migrated towards the anode. The effect of doxycycline, a common antibiotic, on electrotaxis of MRC-5, NCI-H460 and NCI-H520 cells was examined. Doxycycline enhanced the tested cells' motility but inhibited electrotaxis in the NSCLC cells without inhibiting non-cancerous MRC-5 cells. Based on our finding, further in-vivo studies could be devised to investigate the metastasis inhibition effect of doxycycline in an organism level.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Doxiciclina/farmacología , Fenómenos Electrofisiológicos , Neoplasias Pulmonares/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Doxiciclina/uso terapéutico , Ensayos de Selección de Medicamentos Antitumorales , Fibroblastos/efectos de los fármacos , Humanos , Pulmón/citología , Pulmón/patología , Neoplasias Pulmonares/patología , Pruebas de Toxicidad
11.
PLoS One ; 14(1): e0210656, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30633770

RESUMEN

Angiotensin-converting enzyme (ACE) is the primary enzyme that converts angiotensin I (Ang I) to angiotensin II (Ang II) in the renin-angiotensin system (RAS). However, chymase hydrates Ang I to Ang II independently of ACE in some kidney diseases, and it may play an important role. The present study investigated whether chymase played a crucial role in aristolochic acid I (AAI)-induced nephropathy. C57BL/6 mice were treated with AAI via intraperitoneal injection for an accumulated AAI dosage of 45 mg/kg body weight (BW) (15 mg/kg BW per day for 3 days). The animals were sacrificed after acute kidney injury development, and blood, urine and kidneys were harvested for biochemical and molecular assays. Mice exhibited increased serum creatinine, BUN and urinary protein after the AAI challenge. Significant infiltrating inflammatory cells and tubular atrophy were observed in the kidneys, and high immunocytokine levels were detected. Renal RAS-related enzyme activities were measured, and a significantly increased chymase activity and slightly decreased ACE activity were observed in the AAI-treated mice. The renal Ang II level reflected the altered profile of RAS enzymes and was significantly increased in AAI-treated mice. Treatment of AAI-induced nephropathic mice with an ACE inhibitor (ACEI) or chymase inhibitor (CI; chymostatin) reduced renal Ang II levels. The combination of ACEI and CI (ACEI+CI) treatment significantly reversed the AAI-induced changes of Ang II levels and kidney inflammation and injuries. AAI treatment significantly increased renal p-MEK without increasing p-STAT3 and p-Smad3 levels, and p-MEK/p-ERK1/2 signalling pathway was significantly activated. CI and ACEI+CI treatments reduced this AAI-activated signaling pathway. AAI-induced nephropathy progression was significantly mitigated with CI and ACEI+CI treatment. This study elucidates the role of RAS in the pathogenesis of AAI-induced nephropathy.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/metabolismo , Angiotensina II/metabolismo , Ácidos Aristolóquicos/toxicidad , Quimasas/metabolismo , Riñón/metabolismo , Animales , Femenino , Riñón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/fisiología
12.
J Med Chem ; 62(17): 7769-7787, 2019 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-31415176

RESUMEN

While bronchodilators and inhaled corticosteroids are the mainstay of asthma treatment, up to 50% of asthmatics remain uncontrolled. Many studies show that the cysteinyl leukotriene cascade remains highly activated in some asthmatics, even those on high-dose inhaled or oral corticosteroids. Hence, inhibition of the leukotriene C4 synthase (LTC4S) enzyme could provide a new and differentiated core treatment for patients with a highly activated cysteinyl leukotriene cascade. Starting from a screening hit (3), a program to discover oral inhibitors of LTC4S led to (1S,2S)-2-({5-[(5-chloro-2,4-difluorophenyl)(2-fluoro-2-methylpropyl)amino]-3-methoxypyrazin-2-yl}carbonyl)cyclopropanecarboxylic acid (AZD9898) (36), a picomolar LTC4S inhibitor (IC50 = 0.28 nM) with high lipophilic ligand efficiency (LLE = 8.5), which displays nanomolar potency in cells (peripheral blood mononuclear cell, IC50,free = 6.2 nM) and good in vivo pharmacodynamics in a calcium ionophore-stimulated rat model after oral dosing (in vivo, IC50,free = 34 nM). Compound 36 mitigates the GABA binding, hepatic toxicity signal, and in vivo toxicology findings of an early lead compound 7 with a human dose predicted to be 30 mg once daily.


Asunto(s)
Antiasmáticos/farmacología , Asma/tratamiento farmacológico , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Glutatión Transferasa/antagonistas & inhibidores , Pirazinas/farmacología , Administración Oral , Animales , Antiasmáticos/administración & dosificación , Antiasmáticos/química , Asma/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Glutatión Transferasa/metabolismo , Humanos , Estructura Molecular , Pirazinas/síntesis química , Pirazinas/química , Ratas , Relación Estructura-Actividad
13.
Artículo en Inglés | MEDLINE | ID: mdl-29966381

RESUMEN

Air pollution is a very critical issue worldwide, particularly in developing countries. Particulate matter (PM) is a type of air pollution that comprises a heterogeneous mixture of different particle sizes and chemical compositions. There are various sources of fine PM (PM2.5), and the components may also have different effects on people. The pathogenesis of PM2.5 in several diseases remains to be clarified. There is a long history of epidemiological research on PM2.5 in several diseases. Numerous studies show that PM2.5 can induce a variety of chronic diseases, such as respiratory system damage, cardiovascular dysfunction, and diabetes mellitus. However, the epidemiological evidence associated with potential mechanisms in the progression of diseases need to be proved precisely through in vitro and in vivo investigations. Suggested mechanisms of PM2.5 that lead to adverse effects and chronic diseases include increasing oxidative stress, inflammatory responses, and genotoxicity. The aim of this review is to provide a brief overview of in vitro and in vivo experimental studies of PM2.5 in the progression of various diseases from the last decade. The summarized research results could provide clear information about the mechanisms and progression of PM2.5-induced disease.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Tamaño de la Partícula , Material Particulado/toxicidad , Contaminantes Atmosféricos/análisis , Progresión de la Enfermedad , Humanos , Material Particulado/química
14.
RSC Adv ; 8(51): 29013-29021, 2018 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-35547971

RESUMEN

Gold nanoparticles (AuNPs) can be applied in biosensors using fluorescence resonance energy transfer (FRET) technique. Based on this technique, we have established a sensitive and efficient biosensing method by modifying a peptide-probe onto AuNPs to detect proteinase enzyme activity in this study. This biosensing method was designed for chymase activity detection and applied in kidney disease diagnosis. In this study, 16 nm-AuNPs were used to construct the AuNPs-based fluorescence peptide probe (named AuNPs-peptide probe) for chymase activity determination. The peptide sequence is FITC-Acp-DRVYIHPFHLDDDDDC, which comprises a fluorophore at the N-terminal end, an enzyme (chymase) substrate (DRVYIHPFHL), a spacer (DDDDD) and cysteine (C) to conjugate to AuNPs surface. When the enzyme catalyzes the substrate sequence, the fluorophore drifts away from AuNPs and the fluorescence emitting signal can be excited at 495 nm and detected at 515 nm. The results indicate that the time required for the AuNPs-peptide probe for activity detection of chymase was only 15 min, and a linear correlation from 10 to 100 ng mL-1 of chymase was acquired. The chymase reaction would be significantly inhibited by addition of specific chymase inhibitor chymostatin. The AuNPs-peptide probe was tested for the detection of high concentrations of trypsin and chymotrypsin, but only minor emitted fluorescence intensity was detected. According to these results, sensitivity and specificity of the AuNPs-peptide probe for chymase detection have been confirmed. AuNPs-peptide probe was successfully used for the detection of renal chymase activity; and the results indicate the pathogenically increased chymase activity in kidney tissue of nephropathic mice from aristolochic acid I treatment.

15.
Bioresour Technol ; 266: 398-406, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29982063

RESUMEN

High efficiency of microalgal growth and CO2 fixation in a Photobioreactors (PBRs)/Raceway circulating (PsRC) system combined with alkaline-CO2 capturing medium and operation was established and investigated. Compared with a pH 6 medium, the average biomass productivity of Chlorella sp. AT1 cultured in a pH 11 medium at 2 L min-1 circulation rate for 7 days increased by about 2-fold to 0.346 g L-1 d-1. The maximum amount of CO2 fixation and CO2 utilization efficiency of Chlorella sp. AT1 could be obtained at a PBRs to Raceway ratio of 1:10 in an indoor-simulated PsRC system. A similar result was also shown in an outdoor PsRC system with a 10-ton scale for microalgal cultivation. Under the appropriate circulation rate, the stable growth performance of Chlorella sp. AT1 cultured by long-term semi-continuous operation in the 10-ton outdoor PsRC system was observed, and the total amount of CO2 fixation was approximately 1.2 kg d-1 with 50% CO2 utilization efficiency.


Asunto(s)
Ciclo del Carbono , Microalgas , Fotobiorreactores , Biomasa , Dióxido de Carbono , Chlorella
16.
J Med Chem ; 61(5): 1785-1799, 2018 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-29424542

RESUMEN

Synthetic glucocorticoids (GC) are essential for the treatment of a broad range of inflammatory diseases. However, their use is limited by target related adverse effects on, e.g., glucose homeostasis and bone metabolism. Starting from a nonsteroidal GR ligand (4) that is a full agonist in reporter gene assays, we exploited key functional triggers within the receptor, generating a range of structurally diverse partial agonists. Of these, only a narrow subset exhibited full anti-inflammatory efficacy and a significantly reduced impact on adverse effect markers in human cell assays compared to prednisolone. This led to the discovery of AZD9567 (15) with excellent in vivo efficacy when dosed orally in a rat model of joint inflammation. Compound 15 is currently being evaluated in clinical trials comparing the efficacy and side effect markers with those of prednisolone.


Asunto(s)
Antiinflamatorios/farmacología , Descubrimiento de Drogas , Indazoles/farmacología , Piridinas/farmacología , Receptores de Glucocorticoides/agonistas , Administración Oral , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/efectos adversos , Línea Celular , Humanos , Indazoles/administración & dosificación , Indazoles/efectos adversos , Ligandos , Piridinas/administración & dosificación , Piridinas/efectos adversos , Ratas
17.
PLoS One ; 11(6): e0158133, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27352251

RESUMEN

We report the differentiation of neural stem and progenitor cells solely induced by direct current (DC) pulses stimulation. Neural stem and progenitor cells in the adult mammalian brain are promising candidates for the development of therapeutic neuroregeneration strategies. The differentiation of neural stem and progenitor cells depends on various in vivo environmental factors, such as nerve growth factor and endogenous EF. In this study, we demonstrated that the morphologic and phenotypic changes of mouse neural stem and progenitor cells (mNPCs) could be induced solely by exposure to square-wave DC pulses (magnitude 300 mV/mm at frequency of 100-Hz). The DC pulse stimulation was conducted for 48 h, and the morphologic changes of mNPCs were monitored continuously. The length of primary processes and the amount of branching significantly increased after stimulation by DC pulses for 48 h. After DC pulse treatment, the mNPCs differentiated into neurons, astrocytes, and oligodendrocytes simultaneously in stem cell maintenance medium. Our results suggest that simple DC pulse treatment could control the fate of NPCs. With further studies, DC pulses may be applied to manipulate NPC differentiation and may be used for the development of therapeutic strategies that employ NPCs to treat nervous system disorders.


Asunto(s)
Técnicas de Reprogramación Celular/métodos , Corteza Cerebral/citología , Electricidad , Células-Madre Neurales/citología , Neurogénesis , Animales , Células Cultivadas , Técnicas de Reprogramación Celular/instrumentación , Femenino , Ratones , Ratones Endogámicos ICR , Neuronas/citología , Oligodendroglía/citología
18.
Sci Rep ; 6: 26222, 2016 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-27193911

RESUMEN

Applying uniform electric field (EF) in vitro in the physiological range has been achieved in rectangular shaped microchannels. However, in a circular-shaped device, it is difficult to create uniform EF from two electric potentials due to different electrical resistances originated from the length difference between the diameter of the circle and the length of any parallel chord of the bottom circular chamber where cells are cultured. To address this challenge, we develop a three-dimensional (3D) computer-aided designed (CAD) polymeric insert to create uniform EF in circular shaped multi-well culture plates. A uniform EF with a coefficient of variation (CV) of 1.2% in the 6-well plate can be generated with an effective stimulation area percentage of 69.5%. In particular, NIH/3T3 mouse embryonic fibroblast cells are used to validate the performance of the 3D designed Poly(methyl methacrylate) (PMMA) inserts in a circular-shaped 6-well plate. The CAD based inserts can be easily scaled up (i.e., 100 mm dishes) to further increase effective stimulation area percentages, and also be implemented in commercially available cultureware for a wide variety of EF-related research such as EF-cell interaction and tissue regeneration studies.

19.
J Vis Exp ; (106): e53340, 2015 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-26780080

RESUMEN

The behavior of directional cell migration under a direct current electric-field (dcEF) is referred to as electrotaxis. The significant role of physiological dcEF in guiding cell movement during embryo development, cell differentiation, and wound healing has been demonstrated in many studies. By applying microfluidic chips to an electrotaxis assay, the investigation process is shortened and experimental errors are minimized. In recent years, microfluidic devices made of polymeric substances (e.g., polymethylmethacrylate, PMMA, or acrylic) or polydimethylsiloxane (PDMS) have been widely used in studying the responses of cells to electrical stimulation. However, unlike the numerous steps required to fabricate a PDMS device, the simple and rapid construction of the acrylic microfluidic chip makes it suitable for both device prototyping and production. Yet none of the reported devices facilitate the efficient study of the simultaneous chemical and dcEF effects on cells. In this report, we describe our design and fabrication of an acrylic-based multichannel dual-electric-field (MDF) chip to investigate the concurrent effect of chemical and electrical stimulation on lung cancer cells. The MDF chip provides eight combinations of electrical/chemical stimulations in a single test. The chip not only greatly shortens the required experimental time but also increases accuracy in electrotaxis studies.


Asunto(s)
Adenocarcinoma/patología , Dispositivos Laboratorio en un Chip , Neoplasias Pulmonares/patología , Microfluídica/instrumentación , Microfluídica/métodos , Adenocarcinoma del Pulmón , Amidas/farmacología , Línea Celular Tumoral , Movimiento Celular/fisiología , Estimulación Eléctrica , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimetil Metacrilato/química , Piridinas/farmacología
20.
J Pharm Pharmacol ; 65(9): 1419-28, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23927480

RESUMEN

OBJECTIVES: Liver cancer is one of the highest rate diseases in southeastern Asia. Recently, many of functional foods and alternative medicines are very popularly utilized to prevent chronic diseases and cancer in Taiwan. In this study, we wanted to select and develop some of novel effectual agents or phytochemicals of γ-mangostin for clinical management or prevent hepatocellular carcinoma cell (HCC). METHODS: Lipid peroxidation (LPO) is an autocatalytic mechanism which induced tissue injure and carcinogenesis. In this study, the inhibitory activity of γ-mangostin on oxidative damage induced rat mitochondria LPO, the free radical scavenging of γ-mangostin and the apoptotic effects of γ-mangostin on HepG2 cells were investigated. KEY FINDINGS: γ-Mangostin processed activity to inhibit LPO and scavenge 2,2-diphenyl-1-picrylhydrazyl. γ-Mangostin showed antiproliferative activity and induced nuclear condensation and apoptotic bodies appearance under Giemsa staining by microscopic observation. In addition, γ-mangostin showed increases of hypodiploid cells via propidium iodide, 2'7'-dichlorofluorescein diacetate, and 3,3'-dihexyloxacarbocyanine iodide staining by flow cytometry analysis in HepG2 cells. CONCLUSIONS: γ-Mangostin has demonstrated free radical scavenging activity, and antiproliferative and apoptotic activity in HepG2 cells. The proof suggests that γ-mangostin is a lead compound candidate for clinical management or prevent HCC.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Antioxidantes/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Garcinia mangostana/química , Neoplasias Hepáticas/tratamiento farmacológico , Fitoterapia , Xantonas/uso terapéutico , Animales , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Compuestos de Bifenilo/metabolismo , Carcinoma Hepatocelular/metabolismo , Núcleo Celular/efectos de los fármacos , Frutas , Células Hep G2 , Humanos , Peroxidación de Lípido/efectos de los fármacos , Neoplasias Hepáticas/metabolismo , Masculino , Picratos/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Ratas , Ratas Sprague-Dawley , Xantonas/farmacología
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