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A precise correlated color temperature (CCT) tuning method for light-emitting diodes (LEDs) has been developed and is demonstrated in this article. By combining LEDs and a liquid crystal (LC) cell, a light source with continuous CCT variation along a straight track on the chromaticity diagram is achieved. Moreover, the manner of CCT variation can be modulated by choosing appropriate LEDs and phosphors to yield a variation going from 3800 K to 6100 K with the track near the black-body locus. By adapting various developed LC technologies for diverse demands, the performance and applications of LEDs can be greatly improved.
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To reduce side effects and enhance treatment efficacy, study on combination therapy for pancreatic cancer, a deadly cancer, has gained much attraction in recent years. In this study, we propose a novel triple treatment combining propolis and two physical stimuli-thermal cycling-hyperthermia (TC-HT) and low-intensity ultrasound (US). The study found that, after the triple treatment, the cell viability of a human cancer cell line PANC-1 decreased to a level 80% less than the control, without affecting the normal pancreatic cells. Another result was excessive accumulation of reactive oxygen species (ROS) after the triple treatment, leading to the amplification of apoptotic pathway through the MAPK family and mitochondrial dysfunction. This study, to the best of our knowledge, is the first attempt to combine TC-HT, US, and a natural compound in cancer treatment. The combination of TC-HT and US also promotes the anticancer effect of the heat-sensitive chemotherapy drug cisplatin on PANC-1 cells. It is expected that optimized parameters for different agents and different types of cancer will expand the methodology on oncological therapy in a safe manner.
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Hipertermia Inducida , Neoplasias Primarias Múltiples , Neoplasias Pancreáticas , Própolis , Humanos , Própolis/farmacología , Hipertermia Inducida/métodos , Apoptosis , Línea Celular Tumoral , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Neurodegenerative diseases (NDDs) pose a significant global health threat. In particular, Alzheimer disease, the most common type causing dementia, remains an incurable disease. Alzheimer disease is thought to be associated with an imbalance of reactive oxygen species (ROS) in neurons, and scientists considered ROS modulation as a promising strategy for novel remedies. In the study, human neural cell line SH-SY5Y was used in probing the effect of combining noninvasive high-frequency low-intensity pulsed electric field (H-LIPEF) and brain-derived neurotrophic factor (BDNF) in protection against hydrogen peroxide (H2O2)-induced neuron damage. Our result finds that the combination approach has intensified the neuroprotective effect significantly, perhaps due to H-LIPEF and BDNF synergistically increasing the expression level of the phosphorylated epidermal growth factor receptor (p-EGFR), which induces the survival-related mitogen-activated protein kinases (MAPK) proteins. The study confirmed the activation of extracellular signal-regulated kinase (ERK) and the downstream pro-survival and antioxidant proteins as the mechanism underlying neuron protection. These findings highlighted the potential of H-LIPEF combined with BDNF in the treatment of NDDs. Furthermore, BDNF-mimetic drugs combining with noninvasive H-LIPEF to patients is a promising approach worthy of further research. This points to strategies for selecting drugs to cooperate with electric fields in treating neurodegenerative disorders.
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Enfermedad de Alzheimer , Neuroblastoma , Fármacos Neuroprotectores , Humanos , Peróxido de Hidrógeno/farmacología , Factor Neurotrófico Derivado del Encéfalo , Especies Reactivas de Oxígeno/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Línea Celular Tumoral , Fármacos Neuroprotectores/farmacología , Supervivencia Celular , ApoptosisRESUMEN
Despite continuation of some controversies, Alzheimer's disease (AD), the most common cause of dementia nowadays, has been widely believed to derive mainly from excessive ß-amyloid (Aß) aggregation, that would increase reactive oxygen species (ROS) and induce neuroinflammation, leading to neuron loss and cognitive impairment. Existing drugs on Aß have been ineffective or offer only temporary relief at best, due to blood-brain barrier or severe side effects. The study employed thermal cycling-hyperthermia (TC-HT) to ease the Aß-induced cognitive impairments and compared its effect with continuous hyperthermia (HT) in vivo. It established an AD mice model via intracerebroventricular (i.c.v.) injection of Aß25-35, proving that TC-HT is much more effective in alleviating its performance decline in Y-maze and novel object recognition (NOR) tests, in comparison with HT. In addition, TC-HT also exhibits a better performance in decreasing the hippocampal Aß and ß-secretase (BACE1) expressions as well as the neuroinflammation markers-ionized calcium-binding adapter molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) levels. Furthermore, the study finds that TC-HT can elevate more protein expressions of insulin degrading enzyme (IDE) and antioxidative enzyme superoxide dismutase 2 (SOD2) than HT. In sum, the study proves the potential of TC-HT in AD treatment, which can be put into application with the use of focused ultrasound (FUS).
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Enfermedad de Alzheimer , Disfunción Cognitiva , Hipertermia Inducida , Ratones , Animales , Secretasas de la Proteína Precursora del Amiloide , Enfermedades Neuroinflamatorias , Ratones Endogámicos C57BL , Ácido Aspártico Endopeptidasas , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/tratamiento farmacológico , Disfunción Cognitiva/terapia , Disfunción Cognitiva/tratamiento farmacológico , Péptidos beta-Amiloides/toxicidad , Péptidos beta-Amiloides/metabolismo , Modelos Animales de EnfermedadRESUMEN
As the most common type of neurodegenerative diseases (NDDs), Alzheimer's disease (AD) is thought to be caused mainly by the excessive aggregation of ß-amyloid protein (Aß). However, a growing number of studies have found that reactive oxygen species (ROS) play a key role in the onset and progression of AD. The present study aimed to probe the neuroprotective effect of high-frequency low-intensity pulsed electric field (H-LIPEF) for SH-SY5Y cells against hydrogen peroxide (H2O2) and Aß-induced cytotoxicity. By looking in a systematic way into the frequency- and amplitude-dependent neuroprotective effect of pulsed electric field (PEF), the study finds that H-LIPEF at 200 Hz produces the optimal protective effect for SH-SY5Y cells. The underlying mechanisms were confirmed to be due to the activation of extracellular signal-regulated kinase (ERK) pathway and the downstream prosurvival and antioxidant proteins. Because the electric field can be modified to focus on specific area in a non-contact manner, the study suggests that H-LIPEF holds great potential for treating NDDs, whose effect can be further augmented with the administering of drugs or natural compounds at the same time.
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Péptidos beta-Amiloides/toxicidad , Electricidad , Peróxido de Hidrógeno/toxicidad , Sistema de Señalización de MAP Quinasas , Neuroprotección , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Flavonoides/farmacología , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Neuroprotección/efectos de los fármacos , Fosforilación/efectos de los fármacos , Coloración y Etiquetado , Quinasas Asociadas a rho/metabolismoRESUMEN
Neurodegenerative diseases (NDDs) are becoming a major threat to public health, according to the World Health Organization (WHO). The most common form of NDDs is Alzheimer's disease (AD), boasting 60-70% share. Although some debates still exist, excessive aggregation of ß-amyloid protein (Aß) and neurofibrillary tangles has been deemed one of the major causes for the pathogenesis of AD. A growing number of evidences from studies, however, have suggested that reactive oxygen species (ROS) also play a key role in the onset and progression of AD. Although scientists have had some understanding of the pathogenesis of AD, the disease still cannot be cured, with existing treatment only capable of providing a temporary relief at best, partly due to the obstacle of blood-brain barrier (BBB). The study was aimed to ascertain the neuroprotective effect of thermal cycle hyperthermia (TC-HT) against hydrogen peroxide (H2O2) and Aß-induced cytotoxicity in SH-SY5Y cells. Treating cells with this physical stimulation beforehand significantly improved the cell viability and decreased the ROS content. The underlying mechanisms may be due to the activation of Akt pathway and the downstream antioxidant and prosurvival proteins. The findings manifest significant potential of TC-HT in neuroprotection, via inhibition of oxidative stress and cell apoptosis. It is believed that coupled with the use of drugs or natural compounds, this methodology can be even more effective in treating NDDs.
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Péptidos beta-Amiloides/toxicidad , Peróxido de Hidrógeno/toxicidad , Hipertermia Inducida , Estrés Oxidativo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Línea Celular Tumoral , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas de Choque Térmico/metabolismo , Humanos , Insulisina/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismoRESUMEN
Most existing cancer treatments involve high-cost chemotherapy and radiotherapy, with major side effects, prompting effort to develop alternative treatment modalities. It was reported that the combination of thermal-cycling hyperthermia (TC-HT) and phenolic compound exhibited a moderate cytotoxic effect against human pancreatic cancer PANC-1 cells. In this study, we investigate the efficacy of triple combination in PANC-1 cancer cells by adopting low-intensity pulsed electric field (LIPEF) to couple with TC-HT and CGA (chlorogenic acid). The study finds that this triple combination can significantly impede the proliferation of PANC-1 cells, with only about 20% viable cells left after 24h, whereas being non-toxic to normal cells. The synergistic activity against the PANC-1 cells was achieved by inducing G2/M phase arrest and apoptosis, which were associated with up-regulation of p53 and coupled with increased expression of downstream proteins p21 and Bax. Further mechanism investigations revealed that the cytotoxic activity could be related to mitochondrial apoptosis, characterized by the reduced level of Bcl-2, mitochondrial dysfunction, and sequential activation of caspase-9 and PARP. Also, we found that the triple treatment led to the increase of intracellular reactive oxygen species (ROS) production. Notably, the triple treatment-induced cytotoxic effects and the elevated expression of p53 and p21 proteins as well as the increased Bax/Bcl-2 ratio, all could be alleviated by the ROS scavenger, N-acetyl-cysteine (NAC). These findings indicate that the combination of CGA, TC-HT, and LIPEF may be a promising modality for cancer treatment, as it can induce p53-dependent cell cycle arrest and apoptosis through accumulation of ROS in PANC-1 cells.
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Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Ácido Clorogénico/farmacología , Neoplasias Pancreáticas/terapia , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Radiación Electromagnética , Humanos , Hipertermia Inducida/métodos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/metabolismoRESUMEN
With the expansion of the aged population, it is predicted that neurodegenerative diseases (NDDs) will become a major threat to public health worldwide. However, existing therapies can control the symptoms of the diseases at best, rather than offering a fundamental cure. As for the complex pathogenesis, clinical and preclinical researches have indicated that oxidative stress, a central role in neuronal degeneration, is a possible therapeutic target in the development of novel remedies. In this study, the motor neuron-like cell line NSC-34 was employed as an experimental model in probing the effects induced by the combination of non-invasive low intensity pulsed electric field (LIPEF) and fucoidan on the H2O2-induced neuron damage. It was found that single treatment of the LIPEF could protect the NSC-34 cells from oxidative stress, and the protective effect was enhanced by combining the LIPEF and fucoidan. Notably, it was observed that single treatment of the LIPEF obviously suppressed the H2O2-enhanced expression of ROCK protein and increased the phosphorylation of Akt in the H2O2-treated NSC-34 cells. Moreover, the LIPEF can be easily modified to concentrate on a specific area. Accordingly, this technique can be used as an advanced remedy for ROCK inhibition without the drawback of drug metabolism. Therefore, we suggest the LIPEF would be a promising strategy as a treatment for motor neurodegeneration and warrant further probe into its potential in treating other neuronal degenerations.
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Terapia por Estimulación Eléctrica , Neuronas Motoras/metabolismo , Estrés Oxidativo/efectos de los fármacos , Polisacáridos/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Quinasas Asociadas a rho/metabolismo , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Humanos , Ratones , Neuronas Motoras/patología , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/terapiaRESUMEN
Hyperthermia (HT) has shown feasibility and potency as an anticancer therapy. Administration of HT in the chemotherapy has previously enhanced the cytotoxicity of drugs against pancreatic cancer. However, the drugs used when conducting these studies are substantially conventional chemotherapeutic agents that may cause unwanted side effects. Additionally, the thermal dosage in the treatment of cancer cells could also probably harm the healthy cells. The purpose of this work was to investigate the potential of the two natural polyphenolic compounds, epigallocatechin gallate (EGCG) and chlorogenic acid (CGA), as heat synergizers in the thermal treatment of the PANC-1 cells. Furthermore, we have introduced a unique strategy entitled the thermal cycling-hyperthermia (TC-HT) that is capable of providing a maximum synergy and minimal side effect with the anticancer compounds. Our results demonstrate that the combination of the TC-HT and the CGA or EGCG markedly exerts the anticancer effect against the PANC-1 cells, while none of the single treatment induced such changes. The synergistic activity was attributed to the cell cycle arrest at the G2/M phase and the induction of the ROS-dependent mitochondria-mediated apoptosis. These findings not only represent the first in vitro thermal synergistic study of natural compounds in the treatment of pancreatic cancer, but also highlight the potential of the TC-HT as an alternative strategy in thermal treatment.
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Catequina/análogos & derivados , Sinergismo Farmacológico , Neoplasias Pancreáticas/terapia , Polifenoles/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Catequina/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Ácido Clorogénico , Terapia Combinada , Humanos , Hipertermia Inducida , Mitocondrias/efectos de los fármacos , Neoplasias Pancreáticas/patologíaRESUMEN
Cancer is one of the most troublesome diseases and a leading cause of death worldwide. Recently, novel treatments have been continuously developed to improve the disadvantages of conventional therapies, such as prodigious expenses, unwanted side effects, and tumor recurrence. Here, we provide the first non-invasive treatment that has combined epigallocatechin gallate (EGCG), the most abundant catechin in green tea, with a low strength pulsed electric field (PEF) and a low energy ultrasound (US). It has been observed that the cell viability of human pancreatic cancer PANC-1 was decreased approximately to 20% of the control after this combination treatment for 72 h. Besides, the combined triple treatment significantly reduced the high tolerance of HepG2 cells to the EGCG-induced cytotoxicity and similarly exhibited compelling proliferation-inhibitory effects. We also found the combined triple treatment increased the intracellular reactive oxygen species (ROS) and acidic vesicles, and the EGCG-induced inhibition of Akt phosphorylation was dramatically intensified. In this study, the apoptosis inhibitor Z-VAD-FMK and the autophagy inhibitor 3-MA were, respectively, shown to attenuate the anticancer effects of the triple treatment. This indicates that the triple treatment-induced autophagy was switched from cytoprotective to cytotoxic, and hence, cooperatively caused cell death with the apoptosis. Since the EGCG is easily accessible from the green tea and mild for a long-term treatment, and the non-invasive physical stimulations could be modified to focus on a specific location, this combined triple treatment may serve as a promising strategy for anticancer therapy.
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Catequina/análogos & derivados , Neoplasias/metabolismo , Tratamiento de Radiofrecuencia Pulsada , Ondas Ultrasónicas , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Caspasas , Catequina/farmacología , Catequina/uso terapéutico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Terapia Combinada , Humanos , Neoplasias/patología , Neoplasias/terapia , Tratamiento de Radiofrecuencia Pulsada/métodos , Especies Reactivas de Oxígeno/metabolismo , Terapia por Ultrasonido/métodosRESUMEN
BACKGROUND: Chronic adenoid infection by ß-lactam-resistant Haemophilus influenzae type b (Hib) and biofilm formation contribute to adenoid hyperplasia. Middle ear disease consequently remains a critical issue in the pediatric population. The aim of this study was to investigate the correlation of Hib biofilm formation with middle ear effusion with adenoid hyperplasia (MEE-AH) and with pediatric obstructive sleep apnea (OSA). METHODS: A total of 384 patients with adenoidectomy from January 2008 to December 2012 were recruited in this investigation. Thirty-two patients (14 female and 18 male; age 4-13 years) who obtained routine adenoidectomy surgery had Hib-positive cultures were enrolled in a retrospective manner. By using polysomnography, 18 patients were diagnosed as having MEE-AH with chronic adenotonsillitis, and 14 patients were diagnosed as having pediatric OSA. The results of the Hib biofilm, antibiotic resistance profiles, and scanning electron microscopy observation, which correlated with the clinical diagnosis, were analyzed by the chi-square test and Fisher exact test. RESULTS: Biofilm formation by Hib was significantly present in the patients with MEE-AH rather than patients with OSA. ß-lactam-sensitive Hib were resistant to augmentin because of the adenoid biofilm formation. However, this finding was uncommon in the pediatric OSA group. CONCLUSIONS: Properly treating ß-lactam-sensitive Hib infection may be an important issue in reducing MEE-AH and adenoid vegetation in the pediatric population. Further research is warranted to elucidate the association of Hib-related biofilm formation with treatment failure and the need to consider earlier surgical intervention.