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1.
Water Res ; 256: 121566, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38598948

RESUMEN

Microbial fuel cell (MFC) sensing is a promising method for real-time detection of water biotoxicity, however, the low sensing sensitivity limits its application. This study adopted low temperature acclimation as a strategy to enhance the toxicity sensing performance of MFC biosensor. Two types of MFC biosensors were started up at low (10 °C) or warm (25 °C) temperature, denoted as MFC-Ls and MFC-Ws respectively, using Pb2+ as the toxic substance. MFC-Ls exhibited superior sensing sensitivities towards Pb2+ compared with MFC-Ws at both low (10 °C) and warm (25 °C) operation temperatures. For example, the inhibition rate of voltage of MFC-Ls was 22.81 % with 1 mg/L Pb2+ shock at 10 °C, while that of MFC-Ws was only 5.9 %. The morphological observation showed the anode biofilm of MFC-Ls had appropriate amount of extracellular polymer substances, thinner thickness (28.95 µm for MFC-Ls and 41.58 µm for MFC-Ws) and higher proportion of living cells (90.65 % for MFC-Ls and 86.01 % for MFC-Ws) compared to that of MFC-Ws. Microbial analysis indicated the enrichment of psychrophilic electroactive microorganisms and cold-active enzymes as well as their sensitivity to Pb2+ shock was the foundation for the effective operation and good performance of MFC-Ls biosensors. In conclusion, low temperature acclimation of electroactive microorganisms enhanced not only the sensitivity but also the temperature adaptability of MFC biosensors.


Asunto(s)
Fuentes de Energía Bioeléctrica , Técnicas Biosensibles , Biopelículas , Temperatura , Aclimatación , Contaminantes Químicos del Agua , Frío , Plomo/toxicidad , Electrodos
2.
Sci Rep ; 12(1): 2904, 2022 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-35190635

RESUMEN

Long QT syndrome (LQTS) is commonly presented with life-threatening ventricular arrhythmias (VA). Renal artery denervation (RDN) is an alternative antiadrenergic treatment that attenuates sympathetic activity. We aimed to evaluate the efficacy of RDN on preventing VAs in LQTS rabbits induced by drugs. The subtypes of LQTS were induced by infusion of HMR-1556 for LQTS type 1 (LQT1), erythromycin for LQTS type 2 (LQT2), and veratridine for LQTS type 3 (LQT3). Forty-four rabbits were randomized into the LQT1, LQT2, LQT3, LQT1-RDN, LQT2-RDN, and LQT3-RDN groups. All rabbits underwent cardiac electrophysiology studies. The QTc interval of the LQT2-RDN group was significantly shorter than those in the LQT2 group (650.08 ± 472.67 vs. 401.78 ± 42.91 ms, p = 0.011). The QTc interval of the LQT3-RDN group was significantly shorter than those in the LQT3 group (372.00 ± 22.41 vs. 335.70 ± 28.21 ms, p = 0.035). The VA inducibility in all subtypes of the LQT-RDN groups was significantly lower than those in the LQT-RDN groups, respectively (LQT1: 9.00 ± 3.30 vs. 47.44 ± 4.21%, p < 0.001; LQT2: 11.43 ± 6.37 vs. 45.38 ± 5.29%, p = 0.026; LQT3: 10.00 ± 6.32 vs. 32.40 ± 7.19%, p = 0.006). This study demonstrated the neuromodulation of RDN leading to electrical remodeling and reduced VA inducibility of the ventricular substrate in LQT models.


Asunto(s)
Arritmias Cardíacas/prevención & control , Desnervación/métodos , Síndrome de QT Prolongado/complicaciones , Arteria Renal/inervación , Animales , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiología , Remodelación Atrial , Modelos Animales de Enfermedad , Electrocardiografía , Ventrículos Cardíacos/fisiopatología , Síndrome de QT Prolongado/clasificación , Conejos
3.
Nanomaterials (Basel) ; 8(4)2018 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-29584656

RESUMEN

To develop a pH-sensitive dual targeting magnetic nanocarrier for chemo-phototherapy in cancer treatment, we prepared magnetic graphene oxide (MGO) by depositing Fe3O4 magnetic nanoparticles on graphene oxide (GO) through chemical co-precipitation. MGO was modified with polyethylene glycol (PEG) and cetuximab (CET, an epidermal growth factor receptor (EGFR) monoclonal antibody) to obtain MGO-PEG-CET. Since EGFR was highly expressed on the tumor cell surface, MGO-PEG-CET was used for dual targeted delivery an anticancer drug doxorubicin (DOX). The physico-chemical properties of MGO-PEG-CET were fully characterized by dynamic light scattering, transmission electron microscopy, X-ray diffraction, Fourier transform Infrared spectroscopy, thermogravimetric analysis, and superconducting quantum interference device. Drug loading experiments revealed that DOX adsorption followed the Langmuir isotherm with a maximal drug loading capacity of 6.35 mg/mg, while DOX release was pH-dependent with more DOX released at pH 5.5 than pH 7.4. Using quantum-dots labeled nanocarriers and confocal microscopy, intracellular uptakes of MGO-PEG-CET by high EGFR-expressing CT-26 murine colorectal cells was confirmed to be more efficient than MGO. This cellular uptake could be inhibited by pre-incubation with CET, which confirmed the receptor-mediated endocytosis of MGO-PEG-CET. Magnetic targeted killing of CT-26 was demonstrated in vitro through magnetic guidance of MGO-PEG-CET/DOX, while the photothermal effect could be confirmed in vivo and in vitro after exposure of MGO-PEG-CET to near-infrared (NIR) laser light. In addition, the biocompatibility tests indicated MGO-PEG-CET showed no cytotoxicity toward fibroblasts and elicited minimum hemolysis. In vitro cytotoxicity tests showed the half maximal inhibitory concentration (IC50) value of MGO-PEG-CET/DOX toward CT-26 cells was 1.48 µg/mL, which was lower than that of MGO-PEG/DOX (2.64 µg/mL). The IC50 value could be further reduced to 1.17 µg/mL after combining with photothermal therapy by NIR laser light exposure. Using subcutaneously implanted CT-26 cells in BALB/c mice, in vivo anti-tumor studies indicated the relative tumor volumes at day 14 were 12.1 for control (normal saline), 10.1 for DOX, 9.5 for MGO-PEG-CET/DOX, 5.8 for MGO-PEG-CET/DOX + magnet, and 0.42 for MGO-PEG-CET/DOX + magnet + laser. Therefore, the dual targeting MGO-PEG-CET/DOX could be suggested as an effective drug delivery system for anticancer therapy, which showed a 29-fold increase in therapeutic efficacy compared with control by combining chemotherapy with photothermal therapy.

4.
Immunology ; 144(4): 668-76, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25351608

RESUMEN

T helper type 2 (Th2) cells, which produce interleukin-4 (IL-4), IL-5 and IL-13, control immunity to all forms of allergic inflammatory responses. Interleukin-21 (IL-21) reduces allergic symptoms in murine models and inhibits IL-4-induced IgE secretion by B cells. However, whether or not IL-21 directly affects Th2 cells, which leads to reduced allergic symptoms, is unclear. In this study, we investigated the effects of IL-21 on the differentiation and effector functions of Th2 cells. We found that IL-21 reduced the number of differentiated Th2 cells and these Th2 cells showed a diminished Th2 cytokine production. Interleukin-21 suppressed Th2 cytokine production of already polarized Th2 cells by down-regulation of transcription factor GATA-3. It also induced apoptosis of Th2 cells with decreased anti-apoptotic factor Bcl-2. Intranasal administration of IL-21 at the beginning of ovalbumin (OVA) sensitization or before OVA challenge decreased Th2 cytokines in the bronchoalveolar lavage fluid of OVA/alum-immunized allergic mice. In addition, the inhibitory effects of IL-21 on Th2 effector functions can also be found in allergic patients. Our results demonstrate that IL-21 suppresses the development of Th2 cells and functions of polarized Th2 cells. Hence, the administration of IL-21 may be considered for use as a preventive and therapeutic approach when dealing with Th2-mediated allergic diseases.


Asunto(s)
Antialérgicos/farmacología , Diferenciación Celular/efectos de los fármacos , Interleucinas/farmacología , Hipersensibilidad Respiratoria/prevención & control , Células Th2/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Estudios de Casos y Controles , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Factor de Transcripción GATA3/metabolismo , Genes Codificadores de los Receptores de Linfocitos T , Humanos , Interleucinas/biosíntesis , Interleucinas/genética , Ratones Endogámicos BALB C , Ratones Transgénicos , Ovalbúmina , Fenotipo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Recombinantes/farmacología , Hipersensibilidad Respiratoria/genética , Hipersensibilidad Respiratoria/inmunología , Hipersensibilidad Respiratoria/metabolismo , Hipersensibilidad Respiratoria/patología , Rinitis Alérgica/inmunología , Rinitis Alérgica/metabolismo , Células Th2/inmunología , Células Th2/metabolismo , Células Th2/patología
5.
Artículo en Inglés | MEDLINE | ID: mdl-25202332

RESUMEN

Background. Limited scientific evidence supports the positive effects of traditional Chinese medicine (TCM) for treating dysmenorrhea. Thus, an observation period of 3 months could verify the ancient indication that TCM treatments effectively alleviate menstrual cramps in women with primary dysmenorrhea or endometriosis. Methods. A prospective, nonrandomized study (primary dysmenorrhea and endometriosis groups) was conducted in women with dysmenorrhea for more than three consecutive menstrual cycles. All patients received TCM prescriptions based on bian zheng lun zhi theory 14 days before menstruation for a period of 12 weeks. Pain intensity was evaluated using a 10-cm visual analogue scale and two validated questionnaires (the Menstrual Distress Questionnaire and the World Health Organization Quality of Life questionnaire). Results. Of the initial 70 intent-to-treat participants, the women with dysmenorrhea reported significant alleviation of cramps during menstruation after the 12-week TCM treatment. Mixed model analysis revealed that TCM prescriptions were more effective in alleviating fatigue, hot flashes, dizziness, painful breasts, excitement, and irritability in the primary dysmenorrhea group (N = 36) than in the endometriosis group (N = 34). Conclusion. TCM prescriptions based on syndrome differentiation theory might be a potentially viable choice for treating painful menstruation and premenstrual symptoms after ruling out endometriosis.

6.
Ann Plast Surg ; 71 Suppl 1: S13-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24284735

RESUMEN

The reconstruction of a through-and-through cheek defect with oral commissure involvement can be challenging. When attempting to reconstruct its seam-like structure or to replace its supple lip tissue, postoperative morbidities such as drooling, microstomia, and poor aesthetic appearance can often occur and be difficult to correct. After inspecting the oral commissure, one can observe that the morphology of the upper lip acts as a "drape" hanging over the upper teeth, whereas the lower lip functions similarly to a "dam" holding the constant pour of saliva within the oral cavity. We noted that if we tailored a single fasciocutaneous flap to satisfy these morphologies during reconstruction, not only were the mentioned morbidities of reconstruction greatly diminished, but the reconstructed oral commissure could also spontaneously mimic the contralateral side in form. We presented 10 consecutive patients with cheek defects with concomitant oral commissure involvement, which underwent reconstruction by using a single-folded fasciocutaneous flap. We described how the flaps are tailored to suit the mentioned upper and lower lip morphology. For certain defects, such as a cheek defect with oral commissure involvement, the loss of functional morphology greatly outweighs its anatomical or tissue losses. Our method provides a simple and straightforward surgical option in this area, which was previously perceived as a challenging reconstruction site.


Asunto(s)
Mejilla/cirugía , Labio/cirugía , Neoplasias de la Boca/cirugía , Colgajo Perforante , Procedimientos de Cirugía Plástica/métodos , Adulto , Humanos , Masculino , Persona de Mediana Edad
7.
Influenza Other Respir Viruses ; 7(6): 1210-7, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24010941

RESUMEN

BACKGROUND: Allergic asthma is a globally respiratory inflammatory disease. Influenza virus is a respiratory pathogen that causes yearly epidemics and results in high rates of morbidity and mortality. Patients with allergic asthma had a more severe symptom and a higher mortality when they were infected with influenza virus. Hence, influenza vaccination is recommended for patients with asthma. OBJECTIVES: We evaluated the efficacy and effects of influenza vaccination on allergic asthma in a mouse model. METHODS: Ovalbumin-immunized mice were inoculated with inactivated influenza virus A/Puerto Rico/8/34 (PR8) as vaccines and morbidity or mortality and allergic asthma features of these mice were analyzed. RESULTS: Mice inoculated with inactivated PR8 induced high levels of anti-PR8 IgG2a and upregulation of Toll-like receptor (TLR) 7. Vaccinated allergic mice were healthy when they were challenged with live influenza virus while none of non-vaccinated allergic mice survived. Furthermore, inactivated influenza virus vaccine induced neither extra airway inflammation nor asthma features such as IgE, airway hyper-reactivity, and eosinophilia in allergic mice. Particularly, decreased frequency of immune cell infiltrated airways and Th2 cytokines IL-4 and IL-6 production in the bronchoalveolar lavage fluid were noted in vaccinated allergic mice. These results suggested that inactivated influenza virus vaccine is efficient to protect allergic mice from further influenza infection, and it does not exacerbate but reduces IL-4 and IL-6 of allergic asthma. CONCLUSION: Influenza vaccination is essential and efficient for allergic subjects to protect influenza virus infection.


Asunto(s)
Asma/inmunología , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/inmunología , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/prevención & control , Ovalbúmina/inmunología , Puerto Rico , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología
8.
Biochem Pharmacol ; 82(1): 35-42, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21477582

RESUMEN

Gemcitabine (2'-deoxy-2', 2'-difluorocytidine; Gem) is a nucleoside anti-metabolite and is commonly used for treating various human cancers including human bladder carcinoma. Gemcitabine not only functions as a suicide nucleoside analog but also inhibits DNA polymerase activity and results in the termination of chain elongation. Using 2-dimensional gel electrophoresis analysis, a Gem-induced protein was identified as UBE2M (a.k.a. UBC12), a NEDD8 conjugation E2 enzyme which contributes to protein degradation. Gem induced UBE2M expression at both RNA and protein levels in several human cancer cell lines. The induction of UBE2M by Gem was accompanied by a reduction in p27(Kip1) protein levels, which could be restored by silencing UBE2M expression with siRNA or by treating cells with the proteasome inhibitor MG132, indicating that UBE2M mediates Gem-induced p27(Kip1) protein degradation. The induction of UBE2M and reduction of p27(Kip1) by Gem were prevented by the PI3K inhibitor LY294002. These results indicate that PI3K activity is necessary for Gem-induced UBE2M expression and that UBE2M facilitates degradation of p27(Kip1). Notably, silencing of UBE2M expression reduced Gem sensitivity in NTUB1 cells, suggesting that UBE2M mediates in part cell sensitivity to Gem, possibly by degradation of p27(Kip1). Analysis of Gem-resistant sub lines also showed that loss of UBE2M and increased p27(Kip1) expression were associated with the acquisition of drug resistance. In conclusion, our results demonstrate a role for UBE2M in mediating cytotoxicity of gemcitabine in human urothelial carcinoma cells while also suggesting a potential function of p27(Kip1) in drug resistance.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Desoxicitidina/análogos & derivados , Ubiquitinas/biosíntesis , Western Blotting , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/metabolismo , Carcinoma de Células Transicionales/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromonas/farmacología , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Desoxicitidina/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Elafina/metabolismo , Formazáns/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Humanos , Morfolinas/farmacología , ARN Interferente Pequeño/farmacología , Espectrometría de Masa por Ionización de Electrospray , Sales de Tetrazolio/metabolismo , Ubiquitinas/genética , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Gemcitabina
9.
J Oral Pathol Med ; 37(1): 18-25, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18154573

RESUMEN

BACKGROUND: Overexpression of hypoxia-inducible factor-1 alpha (HIF-1 alpha) has been found to be significantly associated with the tumor invasion, lymph node metastasis, clinical stage, and prognosis of a variety of human cancers. METHODS: This study examined the expression of HIF-1 alpha in 57 specimens of oral squamous cell carcinoma (OSCC), 41 specimens of oral epithelial dysplasia (OED, 12 mild, 17 moderate, and 12 severe OED cases), and 14 specimens of normal oral mucosa (NOM) by immunohistochemistry. RESULTS: We found that the mean nuclear HIF-1 alpha labeling indices (LIs) increased significantly from NOM (9 +/- 6%) through mild OED (25 +/- 18%), moderate OED (41 +/- 27%), and severe OED (42 +/- 22%) to OSCC samples (55 +/- 23%, P < 0.001). A significant correlation was found between the higher mean nuclear HIF-1 alpha LI and OSCCs with larger tumor size (P < 0.001), regional lymph node metastasis (P < 0.001), or more advanced clinical stages (P < 0.001). Only larger tumor size (P = 0.002) and nuclear HIF-1 alpha LI >or= 60% (P = 0.048) were identified as independent unfavorable prognosis factor by multivariate analyses with Cox regression model. Kaplan-Meier curve showed that OSCC patients with a nuclear HIF-1 alpha LI >or= 60% had a significantly poorer cumulative survival than those with a nuclear HIF-1 alpha LI < 60% (log-rank test, P = 0.022). CONCLUSIONS: We conclude that the expression of HIF-1 alpha is an early event in oral carcinogenesis. The nuclear HIF-1 alpha LI in OSCC samples can predict the progression of OSCCs and the survival of OSCC patients.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/biosíntesis , Neoplasias de la Boca/metabolismo , Adulto , Anciano , Consumo de Bebidas Alcohólicas , Análisis de Varianza , Biomarcadores de Tumor , Carcinoma de Células Escamosas/patología , Progresión de la Enfermedad , Femenino , Humanos , Técnicas para Inmunoenzimas , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mucosa Bucal/metabolismo , Neoplasias de la Boca/patología , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patología , Pronóstico , Modelos de Riesgos Proporcionales , Fumar , Taiwán
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