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1.
J Asian Nat Prod Res ; : 1-10, 2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39120438

ABSTRACT

Four new homoisoflavonoids, 7-hydroxy-3-[hydroxy(4'-methoxyphenyl)methyl]-benzopyran-4-one (1), (3R)-7, 8-dihydroxy-3-(4'-methoxybenzyl)-chroman-4-one (2), 7-hydroxy-3-(2'-hydroxy-4'-methoxybenzyl)-chroman-4-one (3), and 7-hydroxy-3-(2'-hydroxy-4'-methoxybenzyl)-benzopyran-4-one (4), were isolated from the seeds of Caesalpinia pulcherrima. The structures of new compounds were elucidated by MS and NMR spectra. Their absolute configurations were assigned using electronic circular dichroism spectrum. Compounds 2 and 4 exhibited cytotoxic effects on MCF-7/TAM cells with the IC50 values of 101.4 ± 0.03 and 93.02 ± 0.03 µM, respectively.

2.
ACS Biomater Sci Eng ; 8(11): 4807-4818, 2022 11 14.
Article in English | MEDLINE | ID: mdl-36222713

ABSTRACT

Multimodal neural interfaces include combined functions of electrical neuromodulation and synchronic monitoring of neurochemical and physiological signals in one device. The remarkable biocompatibility and electrochemical performance of polystyrene sulfonate-doped poly(3,4-ethylenedioxythiophene) (PEDOT:PSS) have made it the most recommended conductive polymer neural electrode material. However, PEDOT:PSS formed by electrochemical deposition, called PEDOT/PSS, often need multiple doping to improve structural instability in moisture, resolve the difficulties of functionalization, and overcome the poor cellular affinity. In this work, inspired by the catechol-derived adhesion and semiconductive properties of polydopamine melanin (PDAM), we used electrochemical oxidation polymerization to develop PDAM-doped PEDOT (PEDOT/PDAM) as a bioactive multimodal neural interface that permits robust electrochemical performance, structural stability, analyte-trapping capacity, and neural stem cell affinity. The use of potentiodynamic scans resolved the problem of copolymerizing 3,4-ethylenedioxythiophene (EDOT) and dopamine (DA), enabling the formation of PEDOT/PDAM self-assembled nanodomains with an ideal doping state associated with remarkable current storage and charge transfer capacity. Owing to the richness of hydrogen bond donors/acceptors provided by the hydroxyl groups of PDAM, PEDOT/PDAM presented better electrochemical and mechanical stability than PEDOT/PSS. It has also enabled high sensitivity and selectivity in the electrochemical detection of DA. Different from PEDOT/PSS, which inhibited the survival of human induced pluripotent stem cell-derived neural progenitor cells, PEDOT/PDAM maintained cell proliferation and even promoted cell differentiation into neuronal networks. Finally, PEDOT/PDAM was modified on a commercialized microelectrode array system, which resulted in the reduction of impedance by more than one order of magnitude; this significantly improved the resolution and reduced the noise of neuronal signal recording. With these advantages, PEDOT/PDAM is anticipated to be an efficient bioactive multimodal neural electrode material with potential application to brain-machine interfaces.


Subject(s)
Induced Pluripotent Stem Cells , Humans , Melanins , Polymers/pharmacology , Neurons/physiology
3.
Front Plant Sci ; 12: 738445, 2021.
Article in English | MEDLINE | ID: mdl-34745173

ABSTRACT

Aroma is an essential quality indicator of oolong tea, a tea derived from the Camellia sinensis L. plant. Carboxylic 6 (C6) acids and their derivative esters are important components of fatty acid (FA)-derived volatiles in oolong tea. However, the formation and regulation mechanism of C6 acid during postharvest processing of oolong tea remains unclear. To gain better insight into the molecular and biochemical mechanisms of C6 compounds in oolong tea, a combined analysis of alcohol dehydrogenase (ADH) activity, CsADH2 key gene expression, and the FA-derived metabolome during postharvest processing of oolong tea was performed for the first time, complemented by CsHIP (hypoxia-induced protein conserved region) gene expression analysis. Volatile fatty acid derivative (VFAD)-targeted metabolomics analysis using headspace solid-phase microextraction-gas chromatography time-of-flight mass spectrometry (HS-SPEM-GC-TOF-MS) showed that the (Z)-3-hexen-1-ol content increased after each turnover, while the hexanoic acid content showed the opposite trend. The results further showed that both the ADH activity and CsADH gene expression level in oxygen-deficit-turnover tea leaves (ODT) were higher than those of oxygen-turnover tea leaves (OT). The C6-alcohol-derived ester content of OT was significantly higher than that of ODT, while C6-acid-derived ester content showed the opposite trend. Furthermore, the HIP gene family was screened and analyzed, showing that ODT treatment significantly promoted the upregulation of CsHIG4 and CsHIG6 gene expression. These results showed that the formation mechanism of oolong tea aroma quality is mediated by airflow in the lipoxygenase-hydroperoxide lyase (LOX-HPL) pathway, which provided a theoretical reference for future quality control in the postharvest processing of oolong tea.

4.
Environ Geochem Health ; 38(1): 183-94, 2016 Feb.
Article in English | MEDLINE | ID: mdl-25859937

ABSTRACT

The main purpose of this study was to monitor ambient air particles and particulate-bound mercury Hg(p) in total suspended particulate (TSP) concentrations and dry deposition at the Hung Kuang (Traffic), Taichung airport and Westing Park sampling sites during the daytime and nighttime, from 2011 to 2012. In addition, the calculated/measured dry deposition flux ratios of ambient air particles and particulate-bound mercury Hg(p) were also studied with Baklanov & Sorensen and the Williams models. For a particle size of 10 µm, the Baklanov & Sorensen model yielded better predictions of dry deposition of ambient air particulates and particulate-bound mercury Hg(p) at the Hung Kuang (Traffic), Taichung airport and Westing Park sampling site during the daytime and nighttime sampling periods. However, for particulates with sizes 20-23 µm, the results obtained in the study reveal that the Williams model provided better prediction results for ambient air particulates and particulate-bound mercury Hg(p) at all sampling sites in this study.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring , Mercury/analysis , Particulate Matter/analysis , Airports , Models, Theoretical , Particle Size , Seasons , Taiwan
5.
Environ Geochem Health ; 36(4): 605-12, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24263618

ABSTRACT

In this investigation, the concentrations of particles in ambient air, gaseous elemental mercury (GEM), and particulate-bound mercury (Hg(p)) in total suspended particulates (TSP) as well as dry deposition at a (Traffic) sampling site at Hung-kuang were studied during the day and night in 2012. The results reveal that the mean concentrations of TSP in ambient air, GEM, and Hg(p) were 69.72 µg/m(3), 3.17, and 0.024 ng/m(3), respectively, at the Hung-kuang (Traffic) sampling site during daytime sampling periods. The results also reveal that the mean rates of dry deposition of particles from ambient air and Hg(p) were 145.20 µg/m(2) min and 0.022 ng/m(2) min, respectively, at the Hung-kuang (Traffic) sampling site during the daytime sampling period. The mean concentrations of TSP in ambient air, GEM, and Hg(p) were 60.56 µg/m(3), 2.74, and 0.018 ng/m(3), respectively, at the Hung-kuang (Traffic) sampling site during the nighttime sampling period. The mean rates of dry deposition of particles and Hg(p) from ambient air were 132.58 µg/m(2) min and 0.016 ng/m(2) min, respectively, at the Hung-kuang (Traffic) sampling site during the nighttime sampling period.


Subject(s)
Mercury/analysis , Particulate Matter/analysis , Air Pollutants/analysis , Environmental Monitoring/methods , Motor Vehicles , Seasons , Taiwan
6.
National Journal of Andrology ; (12): 118-122, 2010.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-252811

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the pathohistological characteristics of the prostate tissues in patients who receive a second TURP and to evaluate their clinical significance.</p><p><b>METHODS</b>We collected surgical specimens from 50 cases of TURP (the control group) and another 50 cases of re-TURP (the re-TURP group), detected the expressions of CD34, vascular endothelial growth factor (VEGF) and androgen receptor (AR) in the prostate tissues by immunohistochemistry (S-P), and determined microvessel density (MVD) and the expressions of VEGF and AR. We performed statistical analyses on the results obtained from the specimens of the control group as well as from those of the first and second operations of the re-TURP group.</p><p><b>RESULTS</b>VEGF and AR expressed in all the specimens. The expressions of VEGF and AR and MVD were significantly higher in the re-TURP group than in the controls (P < 0.05), but showed no significant differences between the first and second operations in the re-TURP group (P > 0.05). Positive correlations were found between the expressions of AR and VEGF, VEGF and MVD, and AR and MVD (r = 0.650, 0.705 and 0.525, P < 0.05).</p><p><b>CONCLUSION</b>Increased AR, VEGF and MVD in the prostatic tissues may be one of the important causes of recurrence of BPH after TURP, and could be considered as the risk factors for postoperative recurrence and targeted indicators for preventive measures.</p>


Subject(s)
Humans , Male , Prostatic Hyperplasia , Metabolism , Pathology , General Surgery , Receptors, Androgen , Metabolism , Reoperation , Transurethral Resection of Prostate , Vascular Endothelial Growth Factor A , Metabolism
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