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1.
Bioengineering (Basel) ; 11(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38671799

RESUMO

OBJECTIVES: This study aimed to establish reference values for fetal aortic isthmus blood flow velocity and associated indices during the first trimester, utilizing a novel ultrasonographic technique known as high-definition flow imaging (HDFI). Additionally, the correlation between Doppler profiles of aortic blood flow and key fetal parameters, including nuchal thickness (NT), crown-rump length (CRL), and fetal heartbeat (FHB), was investigated. METHODS: A total of 262 fetuses were included in the analysis between December 2022 and December 2023. Utilizing 2D power Doppler ultrasound images, aortic blood flow parameters were assessed, including aortic peak systolic velocity (PS), aortic end-diastolic velocity (ED), aortic time average maximal velocity (TAMV), and various indices such as aortic systolic velocity/diastolic velocity (S/D), aortic pulsatile index (PI), aortic resistance index (RI), aortic isthmus flow velocity index (IFI), and aortic isthmic systolic index (ISI). Concurrently, fetal FHB, NT, and CRL were evaluated during early trimester Down syndrome screening. RESULTS: Significant findings include a positive correlation between gestational age (GA) and PS (PS = 3.75 × (GA) - 15.4, r2 = 0.13, p < 0.01), ED (ED = 0.42 × (GA) - 0.61, r2 = 0.04, p < 0.01), PI (PI = 0.07 × (GA) + 1.03, r2 = 0.04, p < 0.01), and TAMV (TAMV = 1.23 × (GA) - 1.66, r2 = 0.08, p < 0.01). In contrast, aortic ISI demonstrated a significant decrease (ISI = -0.03 × (GA) + 0.57, r2 = 0.05, p < 0.05) with gestational age. No significant correlation was observed for aortic RI (p = 0.33), S/D (p = 0.39), and IFI (p = 0.29) with gestational age. Aortic PS exhibited positive correlations with NT (0.217, p = 0.001) and CRL (0.360, p = 0.000) but a negative correlation with FHB (-0.214, p = 0.001). Aortic PI demonstrated positive correlations with CRL (0.208, p = 0.001) and negative correlations with FHB (-0.176, p = 0.005). Aortic TAMV showed positive correlations with NT (0.233, p = 0.000) and CRL (0.290, p = 0.000) while exhibiting a negative correlation with FHB (-0.141, p = 0.026). Aortic ISI demonstrated negative correlations with NT (-0.128, p = 0.045) and CRL (-0.218, p = 0.001) but a positive correlation with FHB (0.163, p = 0.010). CONCLUSIONS: Power Doppler angiography with Doppler ultrasound demonstrates the ability to establish accurate reference values for fetal aortic blood flow during the first trimester of pregnancy. Notably, aortic PS, TAMV, and ISI exhibit significant correlations with NT, CRL, and FHB, with ISI appearing more relevant than IFI, PS, TAMV, and FHB. The utilization of HDFI technology proves advantageous in efficiently detecting the site of the aortic isthmus compared to traditional color Doppler mode in early second trimesters.

2.
Polymers (Basel) ; 15(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37688134

RESUMO

The extensive use of carbon fiber-reinforced plastics (CFRP) in aerospace, civil engineering, and other fields has resulted in a significant amount of waste, leading to serious environmental issues. Finding appropriate methods for recycling CFRP waste and effectively reusing recycled carbon fibers (rCFs) has become a challenging task. This paper presents an overview of the current status of CFRP waste and provides a systematic review and analysis of recycling technologies. In addition to discussing mechanical recycling, thermal decomposition, and chemical solvent degradation methods, the organic alkali/organic solvent method for recycling resins is also elucidated. By introducing the recycling conditions and outcomes of the organic alkali/organic solvent method, the study highlights its significance as a reference for carbon fiber recycling. Furthermore, the paper reviews the current state of rCFs utilization based on its application domains, focusing on research advancements in fiber composites and cementitious composites. Based on these findings, the paper summarizes the existing research limitations and identifies specific areas that require further attention in recycling techniques and rCFs utilization. Lastly, this review provides a prospect on the future of recycling and reusing CFRP waste.

3.
Commun Biol ; 5(1): 454, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35551233

RESUMO

Bacterial polyynes are highly active natural products with a broad spectrum of antimicrobial activities. However, their detailed mechanism of action remains unclear. By integrating comparative genomics, transcriptomics, functional genetics, and metabolomics analysis, we identified a unique polyyne resistance gene, masL (encoding acetyl-CoA acetyltransferase), in the biosynthesis gene cluster of antifungal polyynes (massilin A 1, massilin B 2, collimonin C 3, and collimonin D 4) of Massilia sp. YMA4. Crystallographic analysis indicated that bacterial polyynes serve as covalent inhibitors of acetyl-CoA acetyltransferase. Moreover, we confirmed that the bacterial polyynes disrupted cell membrane integrity and inhibited the cell viability of Candida albicans by targeting ERG10, the homolog of MasL. Thus, this study demonstrated that acetyl-CoA acetyltransferase is a potential target for developing antifungal agents.


Assuntos
Acetil-CoA C-Acetiltransferase , Antifúngicos , Acetil-CoA C-Acetiltransferase/genética , Acetil-CoA C-Acetiltransferase/metabolismo , Antifúngicos/farmacologia , Bactérias/metabolismo , Candida albicans/genética , Candida albicans/metabolismo , Poli-Inos/metabolismo , Poli-Inos/farmacologia
4.
Mol Plant Microbe Interact ; 31(12): 1257-1270, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29877166

RESUMO

Plant viruses cause devastating diseases in plants, yet no effective viricide is available for agricultural application. We screened cultured filtrates derived from various soil microorganisms cultured in vegetable broth that enhanced plant viral resistance. A cultured filtrate, designated F8 culture filtrate, derived from a fungus belonging to the genus Trichosporon, induced strong resistance to various viruses on different plants. Our inoculation assay found the infection rate of Tobacco mosaic virus (TMV)-inoculated Nicotiana benthamiana with F8 culture filtrate pretreatment may decrease to 0%, whereas salicylic acid (SA)-pretreated N. benthamiana attenuated TMV-caused symptoms but remained 100% infected. Tracking Tobacco mosaic virus tagged with green fluorescence protein in plants revealed pretreatment with F8 culture filtrate affected the initial establishment of the virus infection. From F8 culture filtrate, we identified a previously unknown polysaccharide composed of D-mannose, D-galactose, and D-glucose in the ratio 1.0:1.2:10.0 with a α-D-1,4-glucan linkage to be responsible for the induction of plant resistance against viruses through priming of SA-governed immune-responsive genes. Notably, F8 culture filtrate only triggered local defense but was much more effective than conventional SA-mediated systematic acquired resistance. Our finding revealed that microbial cultured metabolites provided a rich source for identification of potent elicitors in plant defense.


Assuntos
Nicotiana/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal/efeitos dos fármacos , Polissacarídeos/farmacologia , Vírus do Mosaico do Tabaco/fisiologia , Trichosporon/metabolismo , Genes Reporter , Filogenia , Doenças das Plantas/virologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/imunologia , Folhas de Planta/virologia , Polissacarídeos/química , Polissacarídeos/imunologia , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacologia , Plântula/efeitos dos fármacos , Plântula/imunologia , Plântula/virologia , Microbiologia do Solo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Nicotiana/efeitos dos fármacos , Nicotiana/virologia , Trichosporon/citologia , Trichosporon/genética , Trichosporon/isolamento & purificação
5.
J Nat Prod ; 81(7): 1527-1533, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-29916245

RESUMO

Application of matrix-assisted laser desorption/ionization imaging mass spectrometry to microbiology and natural product research has opened the door to the exploration of microbial interactions and the consequent discovery of new natural products and their functions in the interactions. However, several drawbacks of matrix-assisted laser desorption/ionization imaging mass spectrometry have limited its application especially to complicated and uneven microbial samples. Here, we applied nanostructured silicon as a substrate for surface-assisted laser desorption/ionization mass spectrometry for microbial imaging mass spectrometry to explore fungal metabolic interactions. We chose Phellinus noxius and Aspergillus strains to evaluate the potential of microbial imaging mass spectrometry on nanostructured silicon because both fungi produce a dense mass of aerial mycelia, which is known to complicate the collection of high-quality imaging mass spectrometry data. Our simple and straightforward sample imprinting method and low background interference resulted in an efficient analysis of small metabolites from the complex microbial interaction samples.


Assuntos
Aspergillus/metabolismo , Basidiomycota/metabolismo , Silício , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Nanoestruturas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
6.
PLoS One ; 13(4): e0196520, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29698535

RESUMO

Potato common scab, which is caused by soil-borne Streptomyces species, is a severe plant disease that results in a significant reduction in the economic value of potatoes worldwide. Due to the lack of efficacious pesticides, crop rotations, and resistant potato cultivars against the disease, we investigated whether biological control can serve as an alternative approach. In this study, multiple Bacillus species were isolated from healthy potato tubers, and Bacillus amyloliquefaciens Ba01 was chosen for further analyses based on its potency against the potato common scab pathogen Streptomyces scabies. Ba01 inhibited the growth and sporulation of S. scabies and secreted secondary metabolites such as surfactin, iturin A, and fengycin with potential activity against S. scabies as determined by imaging mass spectrometry. In pot assays, the disease severity of potato common scab decreased from 55.6 ± 11.1% (inoculated with S. scabies only) to 4.2 ± 1.4% (inoculated with S. scabies and Ba01). In the field trial, the disease severity of potato common scab was reduced from 14.4 ± 2.9% (naturally occurring) to 5.6 ± 1.1% after Ba01 treatment, representing evidence that Bacillus species control potato common scab in nature.


Assuntos
Bacillus amyloliquefaciens/metabolismo , Agentes de Controle Biológico/metabolismo , Doenças das Plantas/prevenção & controle , Solanum tuberosum/microbiologia , Bacillus amyloliquefaciens/classificação , Bacillus amyloliquefaciens/genética , Agentes de Controle Biológico/química , Agentes de Controle Biológico/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Lipopeptídeos/química , Lipopeptídeos/metabolismo , Lipopeptídeos/farmacologia , Espectrometria de Massas , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/farmacologia , Filogenia , Doenças das Plantas/microbiologia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/metabolismo , Solanum tuberosum/crescimento & desenvolvimento , Streptomyces/efeitos dos fármacos , Streptomyces/crescimento & desenvolvimento
7.
Analyst ; 143(4): 981-988, 2018 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376176

RESUMO

Mass spectrometry (MS) interfacing technology provides the means for incorporating microfluidic processing with post MS analysis. In this study, we propose a simple piezo-ring-on-chip microfluidic device for the controlled spraying of MALDI-MS targets. This device uses a low-cost, commercially-available ring-shaped piezoelectric acoustic atomizer (piezo-ring) directly integrated into a polydimethylsiloxane microfluidic device to spray the sample onto the MS target substrate. The piezo-ring-on-chip microfluidic device's design, fabrication, and actuation, and its pulsatile pumping effects were evaluated. The spraying performance was examined by depositing organic matrix samples onto the MS target substrate by using both an automatic linear motion motor, and manual deposition. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was performed to analyze the peptide samples on the MALDI target substrates. Using our technique, model peptides with 10-6 M concentration can be successfully detected. The results also indicate that the piezo-ring-on-chip approach forms finer matrix crystals and presents better MS signal uniformity with little sample consumption compared to the conventional pipetting method.

8.
Molecules ; 21(12)2016 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-27918491

RESUMO

This study tried to clarify the antagonistic effect of the lipopeptides secreted by Bacillus amyloliquefaciens strain BPD1 (Ba-BPD1) against Pyricularia oryzae Cavara (PO). To determine the major antifungal lipopeptides effective against PO, single and dual cultures were carried out in solid-state media. The matrix-assisted laser desorption/ionization-time of flight imaging mass spectrometry (MALDI-TOF IMS) was used to identify the most effective lipopeptide in situ. Meanwhile, the morphology of pathogen fungi treated with lipopeptides was observed via the SEM. Of the three lipopeptide families, surfactin, iturin, and fengycin, the last was identified as the most effective for inhibiting mycelium growth and conidial germination of PO. The conidia and hyphae of fengycin-treated PO were shown to become deformed and tumorous under exposure. This study provides insights into the antagonistic effect of Ba-BPD1 against fungal phytopathogens. Such insights are helpful in the development of reagents for biological control applications.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Bacillus amyloliquefaciens/metabolismo , Proteínas de Bactérias/farmacologia , Lipopeptídeos/farmacologia , Antibiose , Ascomicetos/crescimento & desenvolvimento , Proteínas de Bactérias/biossíntese , Lipopeptídeos/biossíntese , Testes de Sensibilidade Microbiana , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Filogenia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento
9.
Sci Rep ; 6: 32950, 2016 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-27605490

RESUMO

Rice bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most destructive rice diseases worldwide. Therefore, in addition to breeding disease-resistant rice cultivars, it is desirable to develop effective biocontrol agents against Xoo. Here, we report that a soil bacterium Pseudomonas taiwanensis displayed strong antagonistic activity against Xoo. Using matrix-assisted laser desorption/ionization imaging mass spectrometry, we identified an iron chelator, pyoverdine, secreted by P. taiwanensis that could inhibit the growth of Xoo. Through Tn5 mutagenesis of P. taiwanensis, we showed that mutations in genes that encode components of the type VI secretion system (T6SS) as well as biosynthesis and maturation of pyoverdine resulted in reduced toxicity against Xoo. Our results indicated that T6SS is involved in the secretion of endogenous pyoverdine. Mutations in T6SS component genes affected the secretion of mature pyoverdine from the periplasmic space into the extracellular medium after pyoverdine precursor is transferred to the periplasm by the inner membrane transporter PvdE. In addition, we also showed that other export systems, i.e., the PvdRT-OpmQ and MexAB-OprM efflux systems (for which there have been previous suggestions of involvement) and the type II secretion system (T2SS), are not involved in pyoverdine secretion.


Assuntos
Quelantes de Ferro/metabolismo , Oligopeptídeos/metabolismo , Pseudomonas/metabolismo , Sistemas de Secreção Tipo VI/metabolismo , Agentes de Controle Biológico , Genes Bacterianos , Mutagênese , Oligopeptídeos/química , Oligopeptídeos/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Pseudomonas/genética , Sideróforos/química , Sideróforos/genética , Sideróforos/metabolismo , Sistemas de Secreção Tipo VI/genética , Xanthomonas/patogenicidade
10.
Analyst ; 141(16): 4973-81, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27315049

RESUMO

Nanoscale silicon surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) is an emerging matrix-free, highly sensitive MS analysis method. An important challenge in using nanoscale silicon SALDI-MS analysis is the aging and stability of silicon after storage in various environments. No proper nanoscale silicon SALDI-MS activation procedure has been reported to solve this issue. This study investigated the sensitivity, wettability, and surface oxidation behavior of nanoscale silicon surface SALDI-MS in a room, an inert gas atmosphere, and a vacuum environment. A simple vacuum oven desiccation was proposed to activate the SALDI-MS surface, and the limit of detection was further enhanced 1000 times to a 500 attomole level using this approach. The long-term stability and desorption/ionization mechanism were also investigated.

11.
Pol J Pathol ; 65(3): 194-201, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25372416

RESUMO

The activation of vascular endothelial cell growth factor receptors (VEGFRs) plays an essential role in cancer progression. In this study, we investigated the expression of phosphorylated VEGFR-2 (or phospho-KDR/Flk-1), the activated form of VEGFR-2, in human colorectal adenomas and colorectal adenocarcinomas. Phospho-KDR/Flk-1 showed weak expression in the normal colorectal tissue. Phospho-KDR/Flk-1 was mainly stained in the cytoplasm of colorectal adenomas, and was stained in both the cytoplasm and nuclei colorectal adenocarcinomas. There was no indication of increased phospho-KDR/Flk-1 expression in the colorectal adenocarcinomas, as compared to that of colorectal adenomas. Furthermore, there was an inverse relationship of phospho-KDR/Flk-1 expression with cancer stage (p < 0.0001), lymph node metastasis (p = 0.011), and distant metastasis (p = 0.021) of the colorectal adenocarcinomas. Our results indicate that early stage colorectal adenocarcinomas with highly activated (phosphorylated) VEGFR-2 expression may indicate the significance of neoangiogenesis of the tumors.


Assuntos
Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , Neovascularização Patológica/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenoma/metabolismo , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fosforilação , Prognóstico
12.
Nat Prod Rep ; 31(6): 739-55, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24452118

RESUMO

Covering: up to the end of September 2013 Microorganisms are a plentiful resource for natural products research. Traditionally, natural products discovery from microbial sources depends on the screening of target-mediated inhibition. The natural products identified through this strategy usually correlate to significant microbial phenotypes. However, the target-mediated transcriptions deduced from low concentrations of natural products sometimes do not generate an obvious phenotype. The better understanding of the true biological roles of those microbial natural products will permit the application of rational approaches to the more effective exploitation of their use. Imaging mass spectrometry (IMS) has been developed and applied in many fields for decades. However, the applications of IMS on microbial natural products research have just been recently reported. IMS is one of few tools capable of revealing both phenotype and relevant and irrelevant chemotypes of microorganisms. In this review, we summarize the latest applications of IMS technologies. The challenges and prospect of improvement and application of IMS to microbial natural products research are discussed as well.


Assuntos
Produtos Biológicos/química , Espectrometria de Massas/métodos , Animais , Bactérias/química , Insetos/química , Interações Microbianas , Estrutura Molecular
13.
Molecules ; 18(7): 7600-8, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23812251

RESUMO

A new enynyl-benzenoid, antrocamphin O (1,4,7-dimethoxy-5-methyl-6-(3'-methylbut-3-en-1-ynyl)benzo[d][1,3]dioxide), and the known benzenoids antrocamphin A and 7-dimethoxy-5-methyl-1,3-benzodioxole, were isolated from the fruiting bodies of Antrodia camphorata (Taiwanofungus camphoratus). The structure of antrocamphin O was unambiguously assigned by the analysis of spectral data (including 1D and 2D NMR, high-resolution MS, IR, and UV) and total synthesis. Compound 1 was prepared through the Sonogashira reaction of 5-iodo-4,7-dimethoxy-6-methylbenzene and 2-methylbut-1-en-3-yne as the key step. The benzenoids were tested for cytotoxicity against the HT29, HTC15, DLD-1, and COLO 205 colon cancer cell lines, and activities are reported herein.


Assuntos
Alcinos/farmacologia , Anisóis/farmacologia , Antineoplásicos/farmacologia , Antrodia/química , Benzodioxóis/farmacologia , Alcinos/química , Alcinos/isolamento & purificação , Anisóis/química , Anisóis/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Benzodioxóis/química , Benzodioxóis/isolamento & purificação , Linhagem Celular Tumoral , Descoberta de Drogas , Carpóforos/química , Células HT29 , Humanos
14.
Molecules ; 17(2): 2082-90, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22354186

RESUMO

Two new abietane type diterpenoids, namely seco-helioscopinolide (1) and 3b,7b-dihydroxy-ent-abieta-8,13-diene-12,16-olide (2) were isolated from the aerial parts of Euphorbia formosana Hayata together with helioscopinolide A (3), helioscopinolide B (4), helioscopinolide C (5) and ent-(5b,8a,9b,10a,12a)-12-hydroxyatis-16-ene-3,14-dione (6). The structures of compounds 1-6 were elucidated by analyzing their spectroscopic data and comparison with the literature. Further biological tests by gelatin zymographic analysis revealed that 3-5 significantly up-regulated the expressions and activation of MMP-2 and -9 in human fibrosarcoma cell line HT1080.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Diterpenos/química , Diterpenos/farmacologia , Euphorbia/química , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Linhagem Celular Tumoral , Fibrossarcoma/tratamento farmacológico , Fibrossarcoma/enzimologia , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia
15.
Planta Med ; 77(9): 929-33, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21243587

RESUMO

Two new steroidal saponins, 8 and 10, along with 7 known steroidal sapogenins and saponins (1-7) and a furostanol saponin (9) were isolated from Agave sisalana Perrine ex Engelm. The structures of these two new compounds were identified and characterized by 1D and 2D NMR spectroscopy and mass spectrometry. In addition, acid hydrolysis and GC-FID were used to confirm the sugar moieties of 8 and 10. The cytotoxic effects of 1-10 on MCF-7, NCI-H460, and SF-268 cancer cells were evaluated, and among them, compound 10 proved to be the most cytotoxic with IC50 values of 1.2, 3.8, and 1.5 µM, respectively.


Assuntos
Agave/química , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/química , Saponinas/farmacologia , Esteroides/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Folhas de Planta/química , Sapogeninas/química , Sapogeninas/isolamento & purificação , Sapogeninas/farmacologia , Saponinas/química , Saponinas/isolamento & purificação , Esteroides/química , Esteroides/isolamento & purificação
16.
J Nat Prod ; 72(11): 1960-3, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19860383

RESUMO

Three new clerodane-type diterpenes, 6alpha,16-dihydroxycleroda-3,13-dien-15-oic acid (1), 6alpha,16-dihydroxycleroda-4(18),13-dien-15-oic acid (2), and 4alpha,18beta-epoxy-16-hydroxyclerod-13-en-15-oic acid (3), and four new protoberberine alkaloids, (-)-8-oxo-10-hydroxy-2,3,9-trimethoxyberberine (4), (-)-8-oxo-2,11-dihydroxy-3,10-dimethoxyberberine (5), (-)-8-oxo-11-hydroxy-2,3,9,10-tetramethoxyberberine (6), and (-)-8-oxo-2,10-dihydroxy-3,9,11-trimethoxyberberine (7), together with 11 known substances, were isolated from a methanol extract of the stems of Polyalthia longifolia var. pendula. The structures of 1-7 were elucidated on the basis of spectroscopic data analysis. Compounds were evaluated for their antiproliferative activities against A549 and MCF-7 cancer cells, and among the substances tested, only 16-oxo-cleroda-3,13-dien-15-oic acid (8) exhibited cytotoxicity.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Alcaloides de Berberina/isolamento & purificação , Diterpenos Clerodânicos/isolamento & purificação , Plantas Medicinais/química , Polyalthia/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Alcaloides de Berberina/química , Alcaloides de Berberina/farmacologia , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Estrutura Molecular , Caules de Planta/química , Taiwan
17.
Molecules ; 14(8): 2947-58, 2009 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-19701137

RESUMO

Natural products have the potential to be developed into new drugs for the treatment of various diseases. The aim of the present study was to screen the antioxidant activities of some common edible fruits, garden plants and medicinal plants indigenous to Taiwan. This was performed by assessing the activities of lipoxygenase, xanthine oxidase and tyrosinase following incubation with extracts from these plants. A further aim was to use HPLC-DAD and tyrosinase to chromatographically identify the antioxidative constituents obtained from an extract exhibiting strong antioxidative properties. The acetone extracts of 27 cultivated plant species from Taiwan were tested for antioxidant activities towards xanthine oxidase, tyrosinase and lipoxygenase using spectrophotometric assays. Koelreuteria henryi, Prunus campanulata, and Rhodiola rosea showed the highest xanthine oxidase inhibitory activities. Camellia sinensis, Rhodiola rosea, and Koelreuteria henryi exhibited good tyrosinase inhibitory activities and potent anti-lipoxygenase activities. As Koelreuteria henryi had notable significant inhibitory activities towards xanthine oxidase, tyrosinase, and lipoxygenase, it was further tested with tyrosinase and HPLC-DAD. The results from this part of the study revealed that the more powerful the antioxidant capability of the extracted component, the greater the decrease in peak height obtained after reacting with tyrosinase. Additional studies are warranted to further characterize the compounds responsible for the antioxidant properties of the examined extracts.


Assuntos
Antioxidantes/química , Medicamentos de Ervas Chinesas/química , Lipoxigenase/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química , Plantas Medicinais/química , Xantina Oxidase/metabolismo , Acanthaceae/química , Prunus/química , Rhodiola/química , Taiwan
18.
Molecules ; 14(5): 1789-95, 2009 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-19471199

RESUMO

Three known flavones and seven known homoisoflavonoids were isolated from the methanolic extract of the leaves of Agave sisalanaPerrine ex Engelm. Their structures were elucidated on the basis of spectroscopic analysis. The isolated compounds were also evaluated for immunopharmacological activity. PBMC were used as target cells, and cell proliferation was determined by (3)H-thymidine uptake. (+/-)-3,9-Dihydroeucomin (4), dihydrobonducellin (5), and 5,7-dihydroxy-3-(4'-hydroxybenzyl)-4-chromanone (7) showed inhibitory effects on PBMC proliferation activated by PHA with IC(50) values 19.4, 73.8, and 58.8 microM, respectively. All three compounds significantly inhibited the production of IL-2 and IFN-gamma in activated PBMC in a concentration-dependent manner.


Assuntos
Agave/química , Flavonas , Fatores Imunológicos , Isoflavonas , Extratos Vegetais , Agave/anatomia & histologia , Agave/imunologia , Flavonas/imunologia , Flavonas/isolamento & purificação , Fatores Imunológicos/imunologia , Fatores Imunológicos/isolamento & purificação , Isoflavonas/imunologia , Isoflavonas/isolamento & purificação , Estrutura Molecular , Extratos Vegetais/imunologia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química
19.
J Nat Med ; 63(2): 209-14, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19184275

RESUMO

A new flavonol galloylrhamnoside, kaempferol 3-O-(2'',3''-di-O-galloyl)-alpha-L: -rhamnopyranoside, and a new lignan glycoside, hinokinin 7-O-beta-D: -glucopyranoside were isolated from the leaves of Koelreuteria henryi, along with 18 known compounds, including six flavonol glycosides (3-8), three lignans (9-11), four chlorophyll derivatives (12-15), two steroids (16, 17), and three aromatic compounds (18-20). The structures were determined on the basis of spectral analysis and chemical evidence. The scavenging effect of 1-8 and 20 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 5, 6, and 20 showed more potent activity than that of trolox.


Assuntos
Antioxidantes/farmacologia , Flavonóis/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Sapindaceae/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo , Cromanos/farmacologia , Dioxóis/isolamento & purificação , Dioxóis/farmacologia , Flavonóis/farmacologia , Sequestradores de Radicais Livres/isolamento & purificação , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Quempferóis/isolamento & purificação , Quempferóis/farmacologia , Lignanas/isolamento & purificação , Lignanas/farmacologia , Medicina Tradicional Chinesa , Picratos , Folhas de Planta , Proantocianidinas/isolamento & purificação , Proantocianidinas/farmacologia , Análise Espectral , Taiwan
20.
J Chin Med Assoc ; 70(2): 76-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17339149

RESUMO

Mixed germ cell tumors with non-germ cell malignant components rarely occur in the anterior mediastinum. We report a case of a 34-year-old man who presented with an anterior mediastinum mass. Mixed germ cell tumor was initially diagnosed based on the pathologic findings of germinoma on thoracoscopic biopsy and clinical findings of elevated serum alpha-fetoprotein and beta-human chorionic gonadotropin. The patient received preoperative chemotherapy and subsequent complete resection of the residual tumor. Pathologic examination of the excised specimen showed predominantly malignant ganglioneuroma and small residual foci of teratoma. To our knowledge, this is the first reported case of a malignant ganglioneuroma arising from mediastinal mixed germ cell tumor.


Assuntos
Ganglioneuroma/etiologia , Neoplasias do Mediastino/complicações , Neoplasias Embrionárias de Células Germinativas/complicações , Adulto , Ganglioneuroma/patologia , Ganglioneuroma/terapia , Humanos , Masculino , Neoplasias do Mediastino/patologia , Neoplasias Embrionárias de Células Germinativas/patologia
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