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1.
Tzu Chi Med J ; 36(2): 142-151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645786

RESUMO

Thyroid nodules (TNs) are pathological changes characterized by abnormal proliferation of thyroid gland tissue. Approximately 19% to 67% of asymptomatic individuals are diagnosed with TNs, with the majority being benign nodules and 4% to 6.5% being thyroid cancer nodules. Western medicine recommends regular examinations and surgery, while traditional Chinese medicine (TCM) provides an alternative choice to maintain thyroid function and reduce the need for surgery. However, in Taiwan, research on TCM treatment for benign TNs is primarily limited to case reports, lacking large-scale and systematic clinical studies. We conducted a search of electronic databases including PubMed, Google Scholar, Wanfang Data, and China National Knowledge Infrastructure to collect clinical trials related to TCM treatment for TNs. Our goal is to provide new treatment options, further validate the value of TCM in the treatment of TNs, and lay a foundation for future clinical research.

2.
Environ Pollut ; 345: 123425, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38266700

RESUMO

Ultraviolet light-emitting diodes (UV-LEDs), as a novel ultraviolet light source with flexible pulse mode, has gained significant attention for applications in water disinfection and food sterilization. This study investigated the comparative inactivation efficiency of Tetraselmis sp. with continuous and pulsed UV-LEDs irradiation, exploring different wavelengths, duty rates and pulse frequencies. The results reveal a significant enhancement in inactivation efficiency (p < 0.05) under pulsed conditions even at the same UV dose, with inactivation efficiency increasing as duty rate or pulse frequency decreases. The optimal conditions for achieving peak inactivation efficacy are identified as a duty rate of 50% and a pulse frequency of 5 Hz. Within this parameter space, pulsed irradiation leads to a remarkable 1.7-fold increase in inactivation efficiency at UV265 nm and a 1.5-fold increase at UV285 nm compared to continuous irradiation, respectively. Additionally, the disruptive impacts on photosynthetic performance are more pronounced with pulsed irradiation, particularly at the 5 Hz pulse frequency. In shed of these findings, the application of pulsed UV-LEDs irradiation emerges as a promising alternative to the conventional continuous UV disinfection methods in the area of seawater disinfection, offering higher disinfection efficacy and energy consumption.


Assuntos
Raios Ultravioleta , Purificação da Água , Desinfecção/métodos , Purificação da Água/métodos , Água do Mar , Água
3.
Front Pharmacol ; 14: 1293540, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155901

RESUMO

Background: Mass spectrometry metabolomics-based data-processing approaches have been developed for drug metabolite profiling. However, existing approaches cannot be used to comprehensively identify drug metabolites with high efficacy. Methods: Herein, we propose a two-stage data-processing approach for effective and comprehensive drug metabolite identification. The approach combines dose-response experiments with stable isotope tracing (SIT). Rosiglitazone (ROS), commonly used to treat type 2 diabetes, was employed as a model drug. Results: In the first stage of data processing, 1,071 features exhibited a dose-response relationship among 22,597 features investigated. In the second stage, these 1,071 features were screened for isotope pairs, and 200 features with isotope pairs were identified. In time-course experiments, a large proportion of the identified features (69.5%: 137 out of 200 features) were confirmed to be possible ROS metabolites. We compared the validated features identified using our approach with those identified using a previously reported approach [the mass defect filter (MDF) combined with SIT] and discovered that most of the validated features (37 out of 42) identified using the MDF-SIT combination were also successfully identified using our approach. Of the 143 validated features identified by both approaches, 74 had a proposed structure of an ROS-structure-related metabolite; the other 34 features that contained a specific fragment of ROS metabolites were considered possible ROS metabolites. Interestingly, numerous ROS-structure-related metabolites were identified in this study, most of which were novel. Conclusion: The results reveal that the proposed approach can effectively and comprehensively identify ROS metabolites.

4.
Aquat Toxicol ; 208: 98-108, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30641416

RESUMO

Harmful algal blooms (HAB), heavily influenced by human activities, pose serious hazard to aquatic ecology and human health. In this study, we monitored the physiological responses and paralytic shellfish poisoning toxins (PSTs) of the toxin-producing HAB species Alexandrium tamarense under titanium dioxide nanoparticles (nTiO2) exposure in the concentration range of 2-320 mg L-1 over a period of 13 days. The results showed the acute inhibition of nTiO2 on the algal growth, photosynthetic efficiency and esterase activity at all concentrations except 2 mg L-1. Nonetheless, they recovered after 13 days nTiO2 exposure from 20 to 80 mg L-1. The EC50 value increased from 85.1 mg L-1 in Day 4 to 140.9 mg L-1 in Day 13. The physiological recovery after prolonged exposure may result from the elimination of excess reactive oxygen species (ROS), a combined outcome of increased nTiO2 aggregation and algal antioxidant defense mechanisms. This observation is supported by the immediately increased antioxidant enzyme activities, including the superoxide dismutase (SOD) and catalase (CAT) activities upon nTiO2 exposure. Moreover, the production of PSTs in A. tamarense significantly increased by 1.41-1.76 folds after chronic nTiO2 exposure at all tested concentrations (p < 0.05), which might also be an adaptive response for the microalgae to overcome the stresses. In particular, the proportions of highly-toxic PSTs analogues GTX2/3, STX and dcSTX were significantly increased upon nTiO2 exposure (p < 0.05). Hence, the chronic nTiO2 exposure might aggravate the ecological impact of HABs. Furthermore investigations on different HAB species, especially those toxin-producing ones, and detail physiological responses are obviously needed.


Assuntos
Dinoflagellida/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Dinoflagellida/efeitos dos fármacos , Dinoflagellida/crescimento & desenvolvimento , Esterases/metabolismo , Matriz Extracelular de Substâncias Poliméricas/química , Proliferação Nociva de Algas/efeitos dos fármacos , Humanos , Hidrodinâmica , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Fotossíntese/efeitos dos fármacos , Fitoplâncton/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Água do Mar/química , Intoxicação por Frutos do Mar , Poluentes Químicos da Água/toxicidade
5.
Sci Total Environ ; 610-611: 356-366, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28806552

RESUMO

Human activities can enhance the frequency, intensity and occurrence of harmful algal blooms (HABs). Engineered nanoparticles (ENPs), contained in many materials, will inevitably enter coastal waters and thus cause unpredictable impacts on aquatic organisms. However, knowledge of the influence of ENPs on HAB species is still lacking. In this study, we examined the effects of titanium dioxide nanoparticles (nTiO2), zinc oxide nanoparticles (nZnO) and aluminum oxide nanoparticles (nAl2O3) on physiological changes and paralytic shellfish poisoning toxins (PSTs) production of Alexandrium tamarense. We found a dose-dependent decrease in photosynthetic activity of A. tamarense under all three ENPs and a significant growth inhibition induced by nZnO. The largest reactive oxygen species (ROS) production was induced by nTiO2, followed by nZnO and nAl2O3. Moreover, the PSTs production rate increased by 3.9-fold for nTiO2 (p<0.01) and 4.5-fold for nAl2O3 (p<0.01) at a concentration of 200mgL-1. The major component, C2 was transformed to its epimer C1 and the proportion of decarbamoyl toxins increased under 200mgL-1 of nZnO and nAl2O3. In addition, the proportion of carbamate toxins increased upon exposure to 2mgL-1 ENPs, while decreased upon exposure to 200mgL-1 ENPs. The changes in PSTs production and composition might be an adaptive response for A. tamarense to overcome the stress of ENPs exposure. This work brings the first evidence that ENP would affect PSTs production and profiles.


Assuntos
Dinoflagellida/efeitos dos fármacos , Proliferação Nociva de Algas , Toxinas Marinhas/biossíntese , Nanopartículas Metálicas/química , Óxido de Alumínio/farmacologia , Titânio/farmacologia , Óxido de Zinco/farmacologia
6.
Sci Total Environ ; 449: 244-52, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23428755

RESUMO

Major fractions of radioiodine ((129)I) are associated with natural organic matter (NOM) in the groundwater and surface soils of the Savannah River Site (SRS). Electrospray ionization coupled to Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) was applied to elucidate the interactions between inorganic iodine species (iodide and iodate) and a fulvic acid (FA) extracted from a SRS surface soil. Iodate is likely reduced to reactive iodine species by the lignin- and tannin-like compounds or the carboxylic-rich alicyclic molecules (CRAM), during which condensed aromatics and lignin-like compounds were generated. Iodide is catalytically oxidized into reactive iodine species by peroxides, while FA is oxidized by peroxides into more aliphatic and less aromatic compounds. Only 9% of the total identified organo-iodine compounds derived from molecules originally present in the FA, whereas most were iodine binding to newly-produced compounds. The resulting iodinated molecules were distributed in three regions in the van Krevelen diagrams, denoting unsaturated hydrocarbons, lignin and protein. Moreover, characteristics of these organo-iodine compounds, such as their relatively low O/C ratios (<0.2 or <0.4) and yet some degree of un-saturation close to that of lignin, have multiple important environmental implications concerning possibly less sterically-hindered aromatic ring system for iodine to get access to and a lower hydrophilicity of the molecules thus to retard their migration in the natural aquatic systems. Lastly, ~69% of the identified organo-iodine species contains nitrogen, which is presumably present as NH2 or HNCOR groups and a ring-activating functionality to favor the electrophilic substitution. The ESI-FTICR-MS technique provides novel evidence to better understand the reactivity and scavenging properties of NOM towards radioiodine and possible influence of NOM on (129)I migration.

7.
Environ Sci Technol ; 46(20): 11251-8, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23030048

RESUMO

Effective collection of trace-level lanthanides and actinides is advantageous for recovery and recycling of valuable resources, environmental remediation, chemical separations, and in situ monitoring. Using isotopic tracers, we have evaluated a number of conventional and nanoporous sorbent materials for their ability to capture and remove selected lanthanides (Ce and Eu) and actinides (Th, Pa, U, and Np) from fresh and salt water systems. In general, the nanostructured materials demonstrated a higher level of performance and consistency. Nanoporous silica surface modified with 3,4-hydroxypyridinone provided excellent collection and consistency in both river water and seawater. The MnO(2) materials, in particular the high surface area small particle material, also demonstrated good performance. Other conventional sorbents typically performed at levels below the nanostructured sorbents and demonstrate a larger variability and matrix dependency.


Assuntos
Elementos da Série Actinoide/análise , Recuperação e Remediação Ambiental/métodos , Elementos da Série dos Lantanídeos/análise , Nanoestruturas/química , Poluentes Químicos da Água/análise , Poluentes Radioativos da Água/análise , Elementos da Série Actinoide/química , Adsorção , Elementos da Série dos Lantanídeos/química , Rios/química , Água do Mar/química , Poluentes Químicos da Água/química , Poluentes Radioativos da Água/química
8.
Biochem J ; 444(2): 333-41, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22428548

RESUMO

GHB (γ-hydroxybutyrate) is both a neurotransmitter and a drug of abuse (date-rape drug). We investigated the catabolism of this compound in perfused rat livers. Using a combination of metabolomics and mass isotopomer analysis, we showed that GHB is metabolized by multiple processes, in addition to its previously reported metabolism in the citric acid cycle via oxidation to succinate. A substrate cycle operates between GHB and γ-aminobutyrate via succinic semialdehyde. Also, GHB undergoes (i) ß-oxidation to glycolyl-CoA+acetyl-CoA, (ii) two parallel processes which remove C-1 or C-4 of GHB and form 3-hydroxypropionate from C-2+C-3+C-4 or from C-1+C-2+C-3 of GHB, and (iii) degradation to acetyl-CoA via 4-phosphobutyryl-CoA. The present study illustrates the potential of the combination of metabolomics and mass isotopomer analysis for pathway discovery.


Assuntos
Fígado/metabolismo , Perfusão , Oxibato de Sódio/metabolismo , Animais , Fígado/enzimologia , Perfusão/métodos , Ratos , Ratos Sprague-Dawley , Especificidade por Substrato
9.
PLoS One ; 6(7): e21865, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21811550

RESUMO

The unique properties of engineered nanoparticles (ENs) that make their industrial applications so attractive simultaneously raise questions regarding their environmental safety. ENs exhibit behaviors different from bulk materials with identical chemical compositions. Though the nanotoxicity of ENs has been studied intensively, their unintended environmental impacts remain largely unknown. Herein we report experimental results of EN interactions with exopolymeric substances (EPS) from three marine phytoplankton species: Amphora sp., Ankistrodesmus angustus and Phaeodactylum tricornutum. EPS are polysaccharide-rich anionic colloid polymers released by various microorganisms that can assemble into microgels, possibly by means of hydrophobic and ionic mechanisms. Polystyrene nanoparticles (23 nm) were used in our study as model ENs. The effects of ENs on EPS assembly were monitored with dynamic laser scattering (DLS). We found that ENs can induce significant acceleration in Amphora sp. EPS assembly; after 72 hours EN-EPS aggregation reached equilibrium, forming microscopic gels of ∼4-6 µm in size. In contrast, ENs only cause moderate assembly kinetic acceleration for A. angustus and P. tricornutum EPS samples. Our results indicate that the effects of ENs on EPS assembly kinetics mainly depend on the hydrophobic interactions of ENs with EPS polymers. The cycling mechanism of EPS is complex. Nonetheless, the change of EPS assembly kinetics induced by ENs can be considered as one potential disturbance to the marine carbon cycle.


Assuntos
Biopolímeros/metabolismo , Nanopartículas/química , Nanotecnologia/métodos , Fitoplâncton/metabolismo , Cálcio/isolamento & purificação , Clortetraciclina/metabolismo , Cinética , Luz , Microscopia de Fluorescência , Nanopartículas/ultraestrutura , Oxazinas/metabolismo , Fitoplâncton/ultraestrutura , Espalhamento de Radiação , Água do Mar
10.
J Agric Food Chem ; 59(7): 3027-34, 2011 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-21375324

RESUMO

γ-Aminobutyric acid (GABA) has several well-known physiological functions including antihypertension and antidepression. In this research, we focus on the antidepressant effects of oral administration of GABA-rich Monascus-fermented product in depression animal model (forced swimming test, FST) by Sprague-Dawley rats, and try to find its possible mechanism in the brain monoamine system. GABA and the Monascus-fermented product (MFP) significantly decreased the duration of immobility time in a short-term test. In a long-term test, the antidepressant-like effect of MFP was better than that of GABA at the same dosage (2.6 mg/kg), and the efficacy of MFP was similar to that of fluoxetine. Moreover, GABA might recover the level of monoamines norepinephrine, dopamine (DA), and 5-hydroxytryptamine (5-HT) in hippocampus and normalize the turnover ratio of 5-HT and DA in hippocampus and amygdala. In addition to the functions of GABA, the MFP has more potential in decreasing the turnover ratio of DA in the frontal cortex and striatum to improve depressive symptoms.


Assuntos
Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , Fermentação , Monascus/metabolismo , Oryza/química , Ácido gama-Aminobutírico/administração & dosagem , Animais , Monoaminas Biogênicas/análise , Química Encefálica , Depressão/etiologia , Modelos Animais de Doenças , Masculino , Oryza/microbiologia , Ratos , Ratos Sprague-Dawley , Natação , Ácido gama-Aminobutírico/análise
11.
Biochem J ; 402(2): 387-95, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17107342

RESUMO

Although resistin was first suggested as a possible link between obesity and diabetes, we have demonstrated previously that expression of resistin is induced by LPS (lipopolysaccharide). In the present study, we showed that LPS increased levels of resistin mRNA and promoter activity in murine RAW264.7 macrophages. Investigation of cis-regulatory elements in the mouse resistin promoter required for LPS-mediated induction showed that an Octamer (ATTTGCAT) element, located at -914 to -907, was required for maximal promoter activity in response to LPS stimulation. Co-transfection of RAW264.7 cells with a resistin promoter-luciferase construct and an Oct-1 or Oct-2 expression plasmid (pCG-Oct-1 or pCG-Oct-2) showed that Oct-2, but not Oct-1, activated the resistin promoter upon LPS treatment. Binding of Oct-2 to the Octamer element was demonstrated by supershift DNA-affinity precipitation and chromatin immunoprecipitation assays. Reverse transcription-PCR and Western blot results showed that levels of Oct-2 mRNA and protein were both up-regulated by LPS in RAW264.7 cells. The LPS-induced increase in Oct-2 protein was inhibited by LY294002 (a phosphoinositide 3-kinase inhibitor) post-transcriptionally, and the inhibition also resulted in a lower response of both resistin mRNA and promoter activity to LPS treatment. Moreover, specific knockdown of Oct-2 by RNA interference impaired the LPS-induced increase in resistin mRNA and promoter activity. Together, these results indicate that Oct-2 is involved in the LPS-mediated induction of resistin gene expression in macrophages and suggest that activation of Oct-2 is a part of LPS signalling pathways in macrophages.


Assuntos
Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fator 2 de Transcrição de Octâmero/metabolismo , Resistina/genética , Região 5'-Flanqueadora , Animais , Sequência de Bases , Linhagem Celular , Cromonas/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Dados de Sequência Molecular , Morfolinas/farmacologia , Mutagênese/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fator 2 de Transcrição de Octâmero/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , Interferência de RNA , RNA Mensageiro/genética , Resistina/metabolismo , Elementos de Resposta/genética , Transativadores/genética , Transfecção
12.
J Biomed Sci ; 13(6): 763-72, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16955349

RESUMO

Bitter gourd (Momordica charantia L.) is a common vegetable in Asia that has been used in traditional medicine for the treatment of Diabetes. PPARs are ligand-dependent transcription factors that belong to the steroid hormone nuclear receptor family and control lipid and glucose homeostasis in the body. We previously reported that the ethyl acetate (EA) extract of bitter gourd activated peroxisome proliferator receptors (PPARs) alpha and gamma. To identify the active compound that activated PPARalpha, wild bitter gourd EA extract was partitioned between n-hexane and 90% methanol/10% H(2)O, and the n-hexane soluble fraction was further separated by silica gel column chromatography and finally by preparative HPLC. A transactivation assay employing a clone of CHOK1 cells stably transfected with a (UAS)(4)-tk-alkaline phosphatase reporter and a chimeric receptor of GAL4-rPPARalpha LBD was used to track the active component. Based on Mass, NMR, and IR spectroscopy, 9cis, 11trans, 13trans-conjugated linolenic acid (9c, 11t, 13t-CLN) was identified as a PPARalpha activator in wild bitter gourd. The isolated 9c, 11t, 13t-CLN rich fraction also significantly induced acyl CoA oxidase (ACO) activity in a peroxisome proliferator-responsive murine hepatoma cell line, H4IIEC3, implying that 9c, 11t, 13t-CLN was able to act on a natural PPARalpha signaling pathway as well. The content of 9c, 11t, 13t-CLN was estimated to be about 7.1 g/kg of our dried wild bitter gourd sample. The concentration of 9c, 11t, 13t-CLN and activation activity in the hydrolyzed EA extract of the seeds was higher than that of the flesh. The potential health benefits of 9c, 11t, 13t-CLN through the PPARalpha regulated mechanism are worthy to be further characterized in in vivo studies.


Assuntos
Momordica charantia/química , PPAR alfa/agonistas , Ácido alfa-Linolênico/farmacologia , Animais , Células CHO , Cricetinae , Cricetulus , Espectrofotometria Ultravioleta , Ácido alfa-Linolênico/química
13.
Environ Sci Technol ; 40(14): 4523-7, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16903295

RESUMO

We examined the uptake of ligand-bound metals (Cd and Zn) by the green mussel Perna viridis using defined artificial seawater. Different free ion concentrations (1 pM to 10 microM) in uptake solutions were created by adding different amounts of total metals (Cd 0.1 nM to 0.1 mM; Zn 0.5 nM to 0.05 mM) and ligands (EDTA, NTA, citric acid). Our results showed that Cd and Zn uptake could not be fully explained by the free Cd and Zn concentrations in the presence of different ligands, indicating that metal-ligand complexes were at least partially available for uptake by the mussels. Total Zn concentrations appeared to be a better predictor of metal uptake than the free Zn ion concentrations in the presence of different ligands. Uptake of lipophilic organic metal complexes was substantially greater than the hydrophilic metal complexes, even though the free ion concentration was comparable or lower. Moreover, the radiolabeled ligand compounds were directly accumulated by the mussels. The accumulation of metal complexes may explain the increased metal uptake with increasing ligand and total metal concentration, even though the free ion metal concentration was constant. Overall, our experimental results indicated that free metal ion cannot fully explain metal uptake since metal complex species were also available to the mussels to some extent, apparently through a co-transport process.


Assuntos
Cobre/metabolismo , Perna (Organismo)/metabolismo , Zinco/metabolismo , Animais , Transporte Biológico , Ligantes
14.
Environ Toxicol Chem ; 24(10): 2657-64, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16268169

RESUMO

Coupled respirometric and radiotracer techniques were applied to simultaneously measure the rates of oxygen and metal uptake in the green mussel Perna viridis. This was performed under different metabolic conditions by varying the ambient oxygen partial pressure (P(O2)), temperature, air exposure, and body size. When the mussels were tested under different hypoxic and anoxic conditions, Cd and Zn uptake decreased with decreasing P(O2), accompanied by a decrease in the ventilation activity of mussels. Significant reduction in metal uptake was observed at a P(O2) level of 3 kPa. Under anoxic conditions, the uptake of Cd and Zn was 1.6 to 2.7 times and 2.8 times, respectively, lower than those measured under normoxia. In contrast, both the absorption efficiencies of Cd and Zn and the oxygen extraction efficiency increased significantly with decreasing P(O2). There were significant correlations between the rates of Cd/Zn and O2 uptake by the mussels when quantified under various P(O2) levels. The uptake of Cd and Zn was temperature dependent and increased with temperature over a range of 15 to 30 degrees C. Significant correlations between the rates of Cd/Zn and O2 uptake were also found in the temperature experiments. With reimmersion of mussels after aerial exposure, the mussels experienced an apparent O2 debt. Metal uptake also increased within the first 15 min followed by gradual recovery to the control levels. Similarly, the quantified uptake rates of Zn were significantly correlated with the O2 uptake in experiments with different sizes of mussels. These results strongly suggest that Cd and Zn uptake are coupled with oxygen uptake in the mussels; thus, physiological processes need to be considered in studying metal accumulation.


Assuntos
Bivalves/metabolismo , Cádmio/farmacocinética , Oxigênio/farmacocinética , Poluentes da Água/farmacocinética , Zinco/farmacocinética , Absorção , Animais , Temperatura , Distribuição Tecidual
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