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1.
Differentiation ; 127: 1-11, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36041259

RESUMEN

The cervical and anterior thoracic regions of mammals generally exhibit similar vertebral numbers and identities along the anterior-posterior axis. The position of the forelimbs along the axial skeleton is also generally conserved. In contrast, the number of lumbar and sacral vertebrae and pelvic position exhibit more variation, correlating with posture and locomotion. The molecular mechanisms that lead to these conserved and variable axial skeletal patterns between species are not fully understood. Here we use a human HOXB1-9 transgene to complement a HoxB1-9 deficiency in the mouse. In TgHOXB1-9 mice, human HOXB1, B2, B3, and B4 (HOXB1-4) genes were expressed in mouse embryos in patterns similar to mouse Hoxb1-4 genes. Human transgene expression rescued the cervical and anterior thoracic vertebral patterning defects of HoxB1-9Δ/Δ mice. In addition, the posterior shift in forelimb position of HoxB1-9Δ/Δ mice was rescued by the transgene. Interestingly, the position of the lumbar-sacral transition in both TgHOXB1-9; HoxB1-9Δ/Δ and TgHOXB1-9; HoxB1-9+/+ mice was altered from six lumbar and four sacral vertebrae found in wild-type controls to five lumbar and five sacral vertebrae. The change in the position of the lumbar-sacral transition consequently altered the position of the pelvis. In contrast to the conserved expression of human HOXB1-4 genes in TgHOXB1-9 mouse embryos, the anterior border of human HOXB9 expression in the neural tube and paraxial mesoderm was shifted posteriorly by 2-3 somites compared to the anterior boundary of endogenous Hoxb9 expression. These findings suggest that conservation and variation in Hoxb/HOXB expression contributes to conserved and species-specific vertebral pattern and limb position.


Asunto(s)
Genes Homeobox , Somitos , Animales , Huesos , Regulación del Desarrollo de la Expresión Génica/genética , Proteínas de Homeodominio/genética , Humanos , Mamíferos/genética , Mamíferos/metabolismo , Ratones , Ratones Transgénicos , Columna Vertebral/metabolismo , Factores de Transcripción/genética
2.
J Nanobiotechnology ; 20(1): 311, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35794602

RESUMEN

The development of optical organic nanoparticles (NPs) is desirable and widely studied. However, most organic dyes are water-insoluble such that the derivatization and modification of these dyes are difficult. Herein, we demonstrated a simple platform for the fabrication of organic NPs designed with emissive properties by loading ten different organic dyes (molar masses of 479.1-1081.7 g/mol) into water-soluble polymer nanosponges composed of poly(styrene-alt-maleic acid) (PSMA). The result showed a substantial improvement over the loading of commercial dyes (3.7-50% loading) while preventing their spontaneous aggregation in aqueous solutions. This packaging strategy includes our newly synthesized organic dyes (> 85% loading) designed for OPVs (242), DSSCs (YI-1, YI-3, YI-8), and OLEDs (ADF-1-3, and DTDPTID) applications. These low-cytotoxicity organic NPs exhibited tunable fluorescence from visible to near-infrared (NIR) emission for cellular imaging and biological tracking in vivo. Moreover, PSMA NPs loaded with designed NIR-dyes were fabricated, and photodynamic therapy with these dye-loaded PSMA NPs for the photolysis of cancer cells was achieved when coupled with 808 nm laser excitation. Indeed, our work demonstrates a facile approach for increasing the biocompatibility and stability of organic dyes by loading them into water-soluble polymer-based carriers, providing a new perspective of organic optoelectronic materials in biomedical theranostic applications.


Asunto(s)
Nanopartículas , Fotoquimioterapia , Colorantes , Polímeros , Agua
3.
Analyst ; 146(12): 3834-3840, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-33913955

RESUMEN

We prepared fine grid patterns on a glass substrate through photolithography of photoresists; we filled photoresist grids with liquid crystals (LCs) to construct LC-based sensors. Scanning electron microscopy images revealed that the photoresist grids were flat, smooth, and 3.0-8.0 µm thick. In contrast to conventional LC-based sensors, in which LCs are filled in metal grids placed on glass substrates, our results proved that LC-based sensors constructed using photoresist grids exhibited a larger signal contrast ratio, better signal stability in aqueous solutions and lower limit of detection for mercuric ions. All these characteristics enhanced the performance of the LC-based sensors.

4.
Analyst ; 146(9): 2919-2927, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-33729239

RESUMEN

A rapid and highly sensitive paper-based colorimetric device for the on-site detection of ammonia (NH3) gas is presented in this study. The detection principle of this device is based upon a change of color from red to yellow on a paper that has been immobilized with a pH indicator, i.e., methyl orange (pKa = 3.4), in the presence of NH3 gas. The color signal of the device can be measured through the hue channel of an HSL system via the application of a smartphone. This device can detect the amount of NH3 gas within 3 min. The linear relationship between the NH3 gas concentration and the hue signal was found to be in the range from 6.0 to 54.0 ppbv with R2 = 0.9971, and the limit of detection was found to be 2.0 ppbv. In addition, this device showed remarkably high selectivity to NH3 gas amongst the other common volatile organic compounds and general gases that are present in environmental air without the assistance of any membrane material. Furthermore, we demonstrated the applicability of this device for the detection of total NH3 gas at a chicken farm and in a laboratory, with relative standard deviations of 6.2% and 5.4%, respectively. The developed NH3 gas device in the study is easy to operate and cost-effective, with the reduction of a large consumption of chemical reagents; also, its signals can be measured simply and then recorded through a smartphone. It is suitable for the application of routine on-site detection of NH3 gas, especially concerning regions which have limited resources.

5.
Opt Express ; 27(12): 17080-17090, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31252925

RESUMEN

In past studies, liquid crystal (LC)-based immunoassays were accomplished by fabricating an LC cell with two pieces of glass slides after immunobinding, which makes the determination of the immunoassay not in real-time and requires trained personnel. Herein, we developed the LC-based immunoassay by using rectangular capillaries as the substrate for immunobinding. The inner surface of rectangular capillaries was decorated with a long alkyl saline, dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOAP), followed by immobilization of human serum albumin (HSA) as the probe. In this situation, the orientation of LC was homeotropic and dark LC image was observed under polarized light. When the solution containing anti-human serum albumin (anti-HSA) were dispensed into the capillary through capillary action, the specific immunobinding between HSA and anti-HSA formed an immunocomplex on the inner surface of capillary, which disrupted the original orientation of LC and led to a dark-to-bright transition of the LC images. The quantification of anti-HSA can be achieved by measuring the length of the bright LC image in the rectangular capillary. By using this immunoassay, the limit of detection (LOD) for anti-HSA is 1 µg/mL, and it did not respond to HSA and anti-human immunoglobulin G (anti-h-IgG). On the other hand, the diversity of the LC-based immunoassay can be extended for HSA detection when we immobilized anti-HSA in the capillary. Because the post-fabrication of LC cell was waived by using rectangular capillaries to develop the LC-based immunoassay, it is more convenient for users to handle and collect more reliable data. Moreover, the results of the immunoassay were visualized through naked-eye and could be recorded by a smartphone; it is more suitable for portable and point-of-care applications.


Asunto(s)
Técnicas Biosensibles/métodos , Inmunoensayo/métodos , Cristales Líquidos/química , Humanos , Imagenología Tridimensional , Albúmina Sérica Humana/análisis , Procesamiento de Señales Asistido por Computador , Teléfono Inteligente
6.
FASEB J ; 31(2): 650-662, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27811062

RESUMEN

Pulmonary arterial hypertension (PAH) is an often fatal disease with limited treatment options. Whereas current data support the notion that, in pulmonary artery endothelial cells (PAECs), expression of transcription factor hypoxia inducible factor-1α (HIF-1α) is increased, the role of HIF-1α in pulmonary artery smooth muscle cells (PASMCs) remains controversial. This study investigates the hypothesis that, in PASMCs from patients with PAH, decreases in HIF-1α expression and activity underlie augmented pulmonary vascular contractility. PASMCs and tissues were isolated from nonhypertensive control patients and patients with PAH. Compared with controls, HIF-1α and Kv1.5 protein expression were decreased in PAH smooth muscle cells (primary culture). Myosin light chain (MLC) phosphorylation and MLC kinase (MLCK) activity-major determinants of vascular tone-were increased in patients with PAH. Cofactors involved in prolyl hydroxylase domain activity were increased in PAH smooth muscle cells. Functionally, PASMC contractility was inversely correlated with HIF-1α activity. In PASMCs derived from patients with PAH, HIF-1α expression is decreased, and MLCK activity, MLC phosphorylation, and cell contraction are increased. We conclude that compromised PASMC HIF-1α expression may contribute to the increased tone that characterizes pulmonary hypertension.-Barnes, E. A., Chen, C.-H., Sedan, O., Cornfield, D. N. Loss of smooth muscle cell hypoxia inducible factor-1α underlies increased vascular contractility in pulmonary hypertension.


Asunto(s)
Hipertensión Pulmonar/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Miocitos del Músculo Liso/metabolismo , Arteria Pulmonar/fisiología , Vasoconstricción/fisiología , Aminoácidos Dicarboxílicos/farmacología , Dimetilsulfóxido/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Prolil Hidroxilasas/genética , Prolil Hidroxilasas/metabolismo
7.
Graefes Arch Clin Exp Ophthalmol ; 256(8): 1403-1410, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29948177

RESUMEN

PURPOSE: To investigate the fixation behavior in macular dystrophy using microperimetry. METHODS: This retrospective study included patients with macular dystrophy and unilateral macular pucker. Macular dystrophic eyes were compared based on fixation within or outside of the atrophic region. The normal fellow eyes in patients with unilateral macular pucker formed the control group. Clinical and demographic characteristics of age, sex, best-corrected visual acuity, spherical equivalent, and fixation behavior (which included foveal mean sensitivity (MS), fixation MS, MS improvement, stability, centrality, and eccentric distance of fixation) were analyzed. A total of 58 patients were recruited, comprising 29 eyes of 29 patients in the macular dystrophy group and 29 eyes of 29 patients in the control group. RESULTS: Compared to the control group, patients with macular dystrophy had significantly poorer visual acuity, foveal MS, fixation MS, stability, and centrality, and more eccentric preferred retinal locations (PRLs). In macular dystrophy, the PRLs were most common on the superior side (48.3%). Compared to fixation in the atrophic region, PRLs out of the atrophic lesion gained more MS (7.41 vs. 0.89 dB, p = 0.001), although with less stable fixation (10.0 vs. 47.4%, p = 0.044). By multivariate linear regression, eccentric distance was found to be significantly associated with MS improvement (p = 0.023). CONCLUSIONS: The commonest location of PRLs in macular dystrophy is anatomically superior to the lesion. The dystrophic eye can gain better sensitivity by using PRLs outside the atrophic area.


Asunto(s)
Fijación Ocular/fisiología , Fóvea Central/patología , Degeneración Macular/fisiopatología , Pruebas del Campo Visual/métodos , Campos Visuales/fisiología , Adolescente , Adulto , Anciano , Niño , Estudios Transversales , Femenino , Angiografía con Fluoresceína , Fondo de Ojo , Humanos , Degeneración Macular/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual , Adulto Joven
8.
Int Ophthalmol ; 38(1): 105-110, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28050730

RESUMEN

PURPOSE: To investigate the risk factors associated with corneal epithelial defects (CED) and delayed healing (exceeding 1 week) following pars plana vitrectomy (PPV). METHODS: This retrospective study enrolled patients who underwent PPV at a single center in Taiwan between 2011 and 2012. Medical records were reviewed, including demographic, underlying disease, surgical indication, operation parameters, and existence of CED. These data were statistically analyzed. All patients were evaluated during follow-ups at day 1 and week 1 after PPV. Patients with persistent CED 1 week after PPV were diagnosed with delayed healing. RESULTS: A total of 255 patients were included in the study, consisting of 139 men and 116 women, with a mean age of 56.9 years. PPV was performed under the indications of rhegmatogenous retinal detachment (RRD), diabetic retinopathy, or vitreoretinal interface disease. Out of 255 eyes, 59 developed CED 1 day after surgery (23.1%), and CED was associated with younger age, diabetes mellitus (DM), RRD, longer duration of surgery, and silicon oil use during surgery. Among them, seven patients (11.9%) demonstrated delayed healing, which was associated with a higher rate of DM (p = 0.085), compared to patients who healed within 1 week. CONCLUSION: Patients with RRD, longer duration of surgery, and DM may be at risk of developing CED after PPV. In addition, patients with DM demonstrated a higher incidence of delayed corneal healing.


Asunto(s)
Enfermedades de la Córnea/etiología , Epitelio Corneal/patología , Complicaciones Posoperatorias/etiología , Vitrectomía/efectos adversos , Adulto , Factores de Edad , Anciano , Complicaciones de la Diabetes , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Aceites de Silicona/administración & dosificación , Cicatrización de Heridas
9.
Genome Res ; 24(2): 267-80, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24310002

RESUMEN

Both diffusible factors acting in trans and chromatin components acting in cis are implicated in gene regulation, but the extent to which either process causally determines a cell's transcriptional identity is unclear. We recently used cell fusion to define a class of silent genes termed "cis-silenced" (or "occluded") genes, which remain silent even in the presence of trans-acting transcriptional activators. We further showed that occlusion of lineage-inappropriate genes plays a critical role in maintaining the transcriptional identities of somatic cells. Here, we present, for the first time, a comprehensive map of occluded genes in somatic cells. Specifically, we mapped occluded genes in mouse fibroblasts via fusion to a dozen different rat cell types followed by whole-transcriptome profiling. We found that occluded genes are highly prevalent and stable in somatic cells, representing a sizeable fraction of silent genes. Occluded genes are also highly enriched for important developmental regulators of alternative lineages, consistent with the role of occlusion in safeguarding cell identities. Alongside this map, we also present whole-genome maps of DNA methylation and eight other chromatin marks. These maps uncover a complex relationship between chromatin state and occlusion. Furthermore, we found that DNA methylation functions as the memory of occlusion in a subset of occluded genes, while histone deacetylation contributes to the implementation but not memory of occlusion. Our data suggest that the identities of individual cell types are defined largely by the occlusion status of their genomes. The comprehensive reference maps reported here provide the foundation for future studies aimed at understanding the role of occlusion in development and disease.


Asunto(s)
Regulación de la Expresión Génica , Silenciador del Gen , Secuencias Reguladoras de Ácidos Nucleicos , Transactivadores/genética , Transcripción Genética , Animales , Fusión Celular , Línea Celular , Cromatina/genética , Metilación de ADN/genética , Genoma , Histonas/genética , Histonas/metabolismo , Ratones , Ratas
10.
Retina ; 37(7): 1263-1269, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27984549

RESUMEN

PURPOSE: To evaluate a new application of an expanded polytetrafluoroethylene (Gore-Tex) vascular graft for use in macular buckling surgery for treatment of highly myopic eyes. METHODS: The Gore-Tex vascular graft was used as a macular buckling material in eight consecutive cases of myopic macular diseases which included fovea detachment, foveoschisis, or macular hole retinal detachment. RESULTS: Retinal reattachment was achieved in all cases except one which had partial resolution (88%). The postoperative best-corrected visual acuity ranged from 20/2000 to 20/100 depending on the degree preexisting macular degeneration, and significant better than the preoperative best-corrected visual acuity (P = 0.048, paired t-test). During the follow-up period, which ranged from 8 months to 3 years, no eye developed buckle-related complications such as infection or dislocation. CONCLUSION: The initial pilot results from this series using a Gore-Tex graft for macular buckling is promising. Throughout the follow-up period, the Gore-Tex was well tolerated in the highly myopic eyes. Large scale and long-term follow-up is warranted.


Asunto(s)
Miopía Degenerativa/complicaciones , Politetrafluoroetileno , Refracción Ocular , Desprendimiento de Retina/cirugía , Esclerótica/cirugía , Anciano , Prótesis Vascular , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Miopía Degenerativa/cirugía , Proyectos Piloto , Diseño de Prótesis , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/etiología , Estudios Retrospectivos , Curvatura de la Esclerótica , Factores de Tiempo , Resultado del Tratamiento , Agudeza Visual
11.
Int Ophthalmol ; 37(3): 513-518, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27422143

RESUMEN

The purpose of this study was to investigate the spectrum of organisms causing endophthalmitis after cataract surgery in a tertiary medical center in Taiwan and the antibiotic susceptibilities. This was a retrospective case series study. Patients with endophthalmitis after cataract surgery from January 2004 to July 2015 were reviewed. The outcome measures included the identification of isolates, antibiotic susceptibilities, and final visual outcomes. Twenty-one organisms were isolated from 19 cases. The most common organisms were Enterococcus in 38.1 %, especially Enterococcus faecalis, followed by Staphylococcus epidermidis in 28.6 % and Staphylococcus aureus in 9.5 %. All of the Gram-positive isolates tested were susceptible to vancomycin (100 %), and ceftazidime and amikacin were susceptible for Gram-negative organisms. The Gram-positive organisms remain to be the predominant cause of postoperative endophthalmitis, and Enterococcus species has had an increasing incidence. Vancomycin is still the most powerful antibiotic for Gram-positive organisms, while ceftazidime and amikacin are effective for Gram-negative bacteria.


Asunto(s)
Antibacterianos/farmacología , Bacterias/aislamiento & purificación , Extracción de Catarata/efectos adversos , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Predicción , Infección de la Herida Quirúrgica/tratamiento farmacológico , Cuerpo Vítreo/microbiología , Bacterias/efectos de los fármacos , Endoftalmitis/tratamiento farmacológico , Endoftalmitis/microbiología , Infecciones Bacterianas del Ojo/microbiología , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos , Infección de la Herida Quirúrgica/microbiología , Agudeza Visual
12.
Anal Chem ; 87(8): 4546-51, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25824970

RESUMEN

We developed a liquid crystal (LC) sensor system for detecting mercuric ion (Hg(2+)) in aqueous solutions. In this system, 4-cyano-4'-pentyl biphenyl (5CB) was doped with a sulfur- and nitrogen-containing ligand 5-(pyridine-4-yl)-2-(5-(pyridin-4-yl)thiophen-2-yl)thiazole (ZT) as the Hg(2+) specific LCs. When the system was immersed in the solution containing Hg(2+), the complex of ZT and Hg(2+) formed, which disrupted the orientation of LC and lead to a dark-to-bright transition of the image of LCs. From mercuric binding titrations monitored by UV-vis spectroscopy, it was found that 1:1 Hg(2+)/ZT complexes were formed. The limit of detection (LOD) of the system to Hg(2+) is 10 µM, and it did not respond to Cd(2+), Zn(2+), Cu(2+), Pb(2+), Fe(+), Mg(2+), Ca(2+), Na(+), and K(+). Besides, we also demonstrated that this system is capable of detecting Hg(2+) in tap water and pond water. Because the signal of this system is colorful under ambient light, which is readily understood by normal users, it can be used as a portable device to monitor the water quality at any location.


Asunto(s)
Cristales Líquidos/química , Mercurio/análisis , Tiazoles/química , Tiofenos/química , Iones/análisis , Ligandos , Espectroscopía de Resonancia Magnética , Soluciones , Espectrofotometría Ultravioleta , Tiazoles/síntesis química , Tiofenos/síntesis química , Agua/química
13.
Opt Express ; 21(18): 21395-402, 2013 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-24104014

RESUMEN

Due to its high electrical conductivity and excellent transmittance at terahertz frequencies, graphene is a promising candidate as transparent electrodes for terahertz devices. We demonstrate a liquid crystal based terahertz phase shifter with the graphene films as transparent electrodes. The maximum phase shift is 10.8 degree and the saturation voltage is 5 V with a 50 µm liquid crystal cell. The transmittance at terahertz frequencies and electrical conductivity depending on the number of graphene layer are also investigated. The proposed phase shifter provides a continuous tunability, fully electrical controllability, and low DC voltage operation.

14.
ACS Appl Mater Interfaces ; 15(37): 44022-44032, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37622729

RESUMEN

Bis(2-phenylpyridine)(acetylacetonate)iridium, Ir(ppy)2(acac), is a benchmark green emitter for phosphorescent organic light-emitting diodes (PhOLEDs). In this work, we reported three positional isomeric cyano-substituted Ir(ppy)2(acac) complexes, i.e., Ir(3-CN), Ir(4-CN), and Ir(10-CN), with the emission in the yellow to red region (544-625 nm). Through theoretical investigation and single-crystal analysis, it was found that the introduction of cyano substitution at various positions of the ppy ligand allows for tuning the electron distribution and coordination bond length of Ir complexes. Therefore, the charge transfer property of Ir complexes is enhanced such that the energy gap of the cyano-substituted Ir(ppy)2(acac) complexes was reduced. In addition, Ir(3-CN), Ir(4-CN), and Ir(10-CN) exhibited high PLQYs of 83, 54, and 75%, respectively, with the phosphorescence lifetime in the range of 0.79-2.08 µs. Notably, the device utilizing Ir(3-CN) as the emitter exhibited a maximum external quantum efficiency (EQE) of 25.4%, current efficiency of 56.9 cd A-1, power efficiency of 68.7 lm W-1, and brightness of 61,340 cd m-2 at 8 V. The EQE of this device remained 24.3 and 19.9% at luminances of 1,000 and 10,000 cd m-2, corresponding to the efficiency roll-off of 4.3 and 21.7%, respectively. Comparing to the Ir complexes using the ligand with an extended conjugated structure, our results demonstrated a simple molecular design strategy for phosphorescence emitters with reduced molecular weight for efficient PhOLEDs in the yellow to red color region.

15.
bioRxiv ; 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37873341

RESUMEN

Bioelectronic fibers hold promise for both research and clinical applications due to their compactness, ease of implantation, and ability to incorporate various functionalities such as sensing and stimulation. However, existing devices suffer from bulkiness, rigidity, limited functionality, and low density of active components. These limitations stem from the difficulty to incorporate many components on one-dimensional (1D) fiber devices due to the incompatibility of conventional microfabrication methods (e.g., photolithography) with curved, thin and long fiber structures. Herein, we introduce a fabrication approach, ‶spiral transformation″, to convert two-dimensional (2D) films containing microfabricated devices into 1D soft fibers. This approach allows for the creation of high density multimodal soft bioelectronic fibers, termed Spiral NeuroString (S-NeuroString), while enabling precise control over the longitudinal, angular, and radial positioning and distribution of the functional components. We show the utility of S-NeuroString for motility mapping, serotonin sensing, and tissue stimulation within the dynamic and soft gastrointestinal (GI) system, as well as for single-unit recordings in the brain. The described bioelectronic fibers hold great promises for next-generation multifunctional implantable electronics.

16.
Mol Vis ; 18: 838-50, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22511847

RESUMEN

PURPOSE: High-mobility group box 1 protein (HMGB1) has been reported to be a potent proangiogenic factor induced by inflammatory stress. In this study, we explore the role of HMGB1 in advanced glycation end products (AGEs)-induced vascular endothelial growth factor A (VEGF-A) production in rat retinal ganglion cell line 5 (RGC-5) cells. METHODS: The VEGF-A protein and mRNA levels in conditioned medium of RGC-5 cells incubated with AGE-modified BSA (AGE-BSA) were examined with real-time PCR and enzyme-linked immunosorbent assay (ELISA), and BSA-treated cells were used as controls. The expression of HMGB1, c-Jun N-terminal kinase (JNK), extracellular-signal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK) was assessed with immunofluorescence and western blot analysis. Reactive oxidative species (ROS) were detected with flow cytometry measurements of peroxide-dependent oxidation of 2'-7'-dichlorofluorescein-diacetate (DCFH-DA). N-Acetyl-L-cysteine (NAC), glycyrrhizin (GZ), and SP600125 were used to block ROS, HMGB1, and JNK, respectively. RESULTS: Compared with the BSA controls, the RGC-5 cells incubated with AGE-BSA showed a dose- and time-dependent increase in VEGF-A mRNA and VEGF-A protein secretion in the supernatant, with the highest levels achieved at 24 h. AGE-BSA stimulated a significant release of HMGB1 in the supernatant and a significant increase of intracellular ROS production at 3 h. NAC blocked HMGB1 production in a dose-dependent manner. Blocking with GZ, NAC, and JNK significantly suppressed AGE-induced VEGF-A production. CONCLUSIONS: HMGB1 is implicated in the production of VEGF-A in retinal ganglion cell line-5 (RGC-5). Blocking HMGB1, ROS, or the JNK pathway may attenuate VEGF-A production, suggesting HMGB1 and related signaling molecules play a role in diabetic retinopathy.


Asunto(s)
Productos Finales de Glicación Avanzada/farmacología , Proteína HMGB1/biosíntesis , ARN Mensajero/biosíntesis , Células Ganglionares de la Retina/metabolismo , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Acetilcisteína/farmacología , Animales , Antracenos/farmacología , Bovinos , Línea Celular , Medios de Cultivo Condicionados/farmacología , Relación Dosis-Respuesta a Droga , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ácido Glicirrínico/farmacología , Proteína HMGB1/metabolismo , MAP Quinasa Quinasa 4/antagonistas & inhibidores , MAP Quinasa Quinasa 4/metabolismo , Ratas , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/efectos de los fármacos , Albúmina Sérica Bovina/farmacología , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
17.
Anal Biochem ; 421(1): 321-3, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22178912

RESUMEN

Conventional immunoassays are often fluorescence- or enzyme-based and require additional readout systems. Here, we report a liquid crystal (LC)-based immunoassay that features a new signal transduction mechanism, whereby the test results appear as colorful spots and can be viewed with the naked eye directly. By using the different colors of LC spots, we can estimate the range of anti-hepatitis B surface antigen concentrations between 300 and 15 nM. Because additional labeling process and readout systems are not required in this immunoassay, it is more suitable for point-of-care diagnosis of hepatitis B in resource-limited regions.


Asunto(s)
Anticuerpos contra la Hepatitis B/análisis , Inmunoensayo/métodos , Animales , Hepatitis B/diagnóstico , Hepatitis B/inmunología , Humanos , Cristales Líquidos , Ratones , Fenómenos Ópticos , Sistemas de Atención de Punto
18.
Biosens Bioelectron ; 199: 113882, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34923309

RESUMEN

Described herein is a liquid crystal (LC)-based aptasensor via employing the reorientation of LC triggered by the conformational changes of a P-shaped DNA structure. The structure consists of a short linker sequence as an immobilizer probe with ability to hybridize with the central part of the intact aptamer (Apt) sequence and an Apt terminal-locker (ATL) strand with complementary segments of the Apt terminal fragments. Bindings of two arm segments of the Apt sequence with the ATL strand enforces it to form a P-shaped configuration on the sensing platform. The selective interaction between the Apt strand and OTA leads to the disassembly of the Apt-ATL hybrid, collapse of the P-shaped structure, and consequently, transition of the optical appearance of the aptasensor texture. Determination of Ochratoxin A (OTA) in foods is an urgent demand in attempt to minimize food safety risks. To demonstrate the feasibility of our aptasensing design, the OTA specific aptamer was selected as a model. The developed LC aptasensor possesses a wide linear range from 0.01 aM to 100 pM, ultra-low limit of detection (LOD) of 0.0078 aM, and quantitative recoveries of 91-103.51% for OTA in rice and grape juice samples. This study proposes a novel and universal LC-based platform for facile, ultra-sensitive, and precision sensing of hazardous analytes in real samples.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Cristales Líquidos , Ocratoxinas , Límite de Detección , Ocratoxinas/análisis
19.
Biosensors (Basel) ; 13(1)2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36671891

RESUMEN

Phycotoxins or marine toxins cause massive harm to humans, livestock, and pets. Current strategies based on ordinary methods are long time-wise and require expert operators, and are not reliable for on-site and real-time use. Therefore, it is urgent to exploit new detection methods for marine toxins with high sensitivity and specificity, low detection limits, convenience, and high efficiency. Conversely, biosensors can distinguish poisons with less response time and higher selectivity than the common strategies. Aptamer-based biosensors (aptasensors) are potent for environmental monitoring, especially for on-site and real-time determination of marine toxins and freshwater microorganisms, and with a degree of superiority over other biosensors, making them worth considering. This article reviews the designed aptasensors based on the different strategies for detecting the various phycotoxins.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Humanos , Toxinas Marinas/análisis , Inocuidad de los Alimentos , Agua Dulce , Técnicas Biosensibles/métodos
20.
Biomolecules ; 12(9)2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36139127

RESUMEN

Inflammatory bowel diseases (IBD) are chronic, recurring gastrointestinal diseases that severely impair health and quality of life. Although therapeutic options have significantly expanded in recent years, there is no effective therapy for a complete and permanent cure for IBD. Well tolerated dietary interventions to improve gastrointestinal health in IBD would be a welcome advance especially with anticipated favorable tolerability and affordability. Soluble protein hydrolysate (SPH) is produced by the enzymatic hydrolysis of commercial food industry salmon offcuts (consisting of the head, backbone and skin) and contains a multitude of bioactive peptides including those with anti-oxidant properties. This study aimed to investigate whether SPH ameliorates gastrointestinal injury in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced mouse colitis model. Mice were randomly assigned to four groups: Control (no colitis), Colitis, Colitis/CP (with control peptide treatment), and Colitis/SPH (with SPH treatment). Colitis was induced by cutaneous sensitization with 1% TNBS on day -8 followed by 2.5% TNBS enema challenge on day 0. Control peptides and SPH were provided to the mice in the Colitis/CP or Colitis/SPH group respectively by drinking water at the final concentration of 2% w/v daily from day -10 to day 4. Then, the colon was harvested on day 4 and examined macro- and microscopically. Relevant measures included disease activity index (DAI), colon histology injury, immune cells infiltration, pro- and anti-inflammatory cytokines and anti-oxidative gene expression. It was found that SPH treatment decreased the DAI score and colon tissue injury when compared to the colitis-only and CP groups. The protective mechanisms of SPH were associated with reduced infiltration of CD4+ T, CD8+ T and B220+ B lymphocytes but not macrophages, downregulated pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-6), and upregulated anti-inflammatory cytokines (transforming growth factor-ß1 and interleukin-10) in the colon tissue. Moreover, the upregulation of anti-oxidative genes, including ferritin heavy chain 1, heme oxygenase 1, NAD(P)H quinone oxidoreductase 1, and superoxide dismutase 1, in the colons of colitis/SPH group was observed compared with the control peptide treatment group. In conclusion, the protective mechanism of SPH is associated with anti-inflammatory and anti-oxidative effects as demonstrated herein in an established mice model of colitis. Clinical studies with SPH as a potential functional food for the prevention or as an adjuvant therapy in IBD may add an effective and targeted diet-based approach to IBD management in the future.


Asunto(s)
Colitis , Agua Potable , Enfermedades Inflamatorias del Intestino , Animales , Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Apoferritinas , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/patología , Citocinas/metabolismo , Agua Potable/efectos adversos , Hemo-Oxigenasa 1/metabolismo , Inflamación/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Ratones , NAD/metabolismo , Hidrolisados de Proteína/metabolismo , Calidad de Vida , Quinonas/uso terapéutico , Superóxido Dismutasa-1/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Trinitrobencenos , Ácido Trinitrobencenosulfónico/efectos adversos , Factor de Necrosis Tumoral alfa/metabolismo
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