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1.
Int J Biol Macromol ; 253(Pt 4): 127078, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37769769

RESUMO

Combination therapy merges chemical photodynamic therapy (CPDT) to improve cancer treatment. It synergizes chemotherapy with photodynamic therapy (PDT), using photosensitizers to produce reactive oxygen species (ROS) when exposed to light, effectively killing drug-resistant cancer cells. It is not affected by drug resistance, making it an attractive option for combination with chemotherapy. In this study, the focus was on the design of a combination therapy of chemotherapy and PDT. They synthesized diatomaceous earth mesoporous silica nanoparticles (dMSN) containing lanthanide metal ions in a PDT composition. These nanoparticles can generate ROS under near-infrared light irradiation and have MRI and fluorescence imaging capabilities, confirming their phototherapeutic effect on HCT116 cancer cells at a 200 µg/mL concentration. Fucoidan, derived from brown algae, was used as the chemotherapy component. The fucoidan extracted from Sargassum oligocystum in Pingtung Haikou showed the highest anticancer activity, with cell viability of 57.4 % at 200 µg/mL on HCT116 cancer cells. For combination therapy, fucoidan was loaded into nanoparticles (dMSN-EuGd@fucoidan). Cell viability experiments revealed that at 200 µg/mL, the cell survival rate of dMSN-EuGd@Fucoidan on HCT116 cancer cells was 47.7 %. Combination therapy demonstrated superior anticancer efficacy compared to PDT or chemotherapy alone, successfully synthesizing nanoparticles for combined chemotherapy and photodynamic therapy.


Assuntos
Diatomáceas , Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Dióxido de Silício/química , Espécies Reativas de Oxigênio , Fármacos Fotossensibilizantes/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
2.
Nutrients ; 14(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558562

RESUMO

Macrophages and microglia are highly versatile cells that can be polarized into M1 and M2 phenotypes in response to diverse environmental stimuli, thus exhibiting different biological functions. In the central nervous system, activated resident macrophages and microglial cells trigger the production of proinflammatory mediators that contribute to neurodegenerative diseases and psychiatric disorders. Therefore, modulating the activation of macrophages and microglia by optimizing the inflammatory environment is beneficial for disease management. Several naturally occurring compounds have been reported to have anti-inflammatory and neuroprotective properties. Zerumbone is a phytochemical sesquiterpenoid and also a cyclic ketone isolated from Zingiber zerumbet Smith. In this study, we found that zerumbone effectively reduced the expression of lipocalin-2 in macrophages and microglial cell lines. Lipocalin-2, also known as neutrophil gelatinase-associated lipocalin (NGAL), has been characterized as an adipokine/cytokine implicated in inflammation. Moreover, supplement with zerumbone inhibited reactive oxygen species production. Phagocytic activity was decreased following the zerumbone supplement. In addition, the zerumbone supplement remarkably reduced the production of M1-polarization-associated chemokines CXC10 and CCL-2, as well as M1-polarization-associated cytokines interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α. Furthermore, the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 and the production of NO were attenuated in macrophages and microglial cells supplemented with zerumbone. Notably, we discovered that zerumbone effectively promoted the production of the endogenous antioxidants heme oxygenase-1, glutamate-cysteine ligase modifier subunit, glutamate-cysteine ligase catalytic subunit, and NAD(P)H quinone oxidoreductase-1 and remarkably enhanced IL-10, a marker of M2 macrophage polarization. Endogenous antioxidant production and M2 macrophage polarization were increased through activation of the AMPK/Akt and Akt/GSK3 signaling pathways. In summary, this study demonstrated the protective role of zerumbone in maintaining M1 and M2 polarization homeostasis by decreasing inflammatory responses and enhancing the production of endogenous antioxidants in both macrophages and microglia cells. This study suggests that zerumbone can be used as a potential therapeutic drug for the supplement of neuroinflammatory diseases.


Assuntos
Glutamato-Cisteína Ligase , Sesquiterpenos , Glutamato-Cisteína Ligase/metabolismo , Glutamato-Cisteína Ligase/farmacologia , Lipocalina-2 , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Citocinas/metabolismo , Microglia , Macrófagos/metabolismo , Sesquiterpenos/farmacologia , Sesquiterpenos/metabolismo , Interleucina-6/metabolismo , Oxirredução
3.
Foods ; 11(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36360061

RESUMO

Butterfly pea flower (BP) is a rich source of bioactive components and can potentially be utilized to produce appealing, wholesome foods. Antioxidant and dietary fiber-enriched breakfast cereals were produced by extrusion cooking using blends of BP and yellow pea flour (YP). BP was added to YP at 0%, 5% and 10% levels (w/w), respectively, and extruded at two temperature profiles with die temperatures of 130 and 150 °C. Incorporation of BP significantly (p < 0.05) improved the total phenolics content, antioxidant properties, and insoluble and total dietary fiber content of the extrudates, with 10% BP extrudates showing the highest values. At a die temperature of 150 °C, the extrudates had a higher expansion ratio, a lower dry hardness, and a higher dry crispiness as compared to those at 130 °C. The color of BP-incorporated extrudates was darker and bluer as compared to the no-BP extrudates. The 10% BP extrudates retained relatively more of their hardness, crispiness, and crunchiness after soaking, indicating a better bowl-life and, therefore, better suitability of this blend formula for breakfast cereal production. Overall, this research shows that healthier breakfast cereals with appealing color and relatively longer bowl-life can be produced using BP, making BP a potential novel ingredient for extrusion formulations.

4.
Psychol Res Behav Manag ; 15: 3069-3080, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36281271

RESUMO

Purpose: The duties related to COVID-19 control and prevention may have caused psychological stress for the individuals in charge (eg, frontline government workers) and have reportedly led to mental health issues, such as insomnia and post-traumatic stress disorder (PTSD). However, the prevalence of these COVID-19-related disorders and their associated factors remain unclear. Therefore, the purpose of the present study was to investigate the prevalence rates of insomnia, PTSD, COVID-19-related self-stigma, and smartphone addiction, along with the identification of risk factors and protective factors for Taiwan frontline government workers with COVID-19 pandemic control duties. Methods: The survey was carried out with 151 participants between September and October 2021. All participants completed the Fear of COVID-19 Scale (assessing fear of COVID-19), Self-Stigma Scale (assessing self-stigma during the COVID-19 pandemic), Smartphone Application-Based Addiction Scale (assessing the risk of smartphone addiction), Insomnia Severity Index (assessing insomnia), Impacts of Event Scale-6 (assessing PTSD), and a self-designed set of questions assessing trait resilience. Results: The results showed that the prevalence rate was 31.1% for insomnia and 33.8% for PTSD. Furthermore, service duration (adjusted odds ratio [AOR] = 0.93; 95% confidence interval [CI] = 0.86, 0.999) and trait resilience (AOR = 0.19; 95% CI = 0.08, 0.46) were protective factors and fear of COVID-19 (AOR = 1.91; 95% CI = 1.02, 3.57) was a risk factor for insomnia. Fear of COVID-19 (AOR = 2.63; 95% CI = 1.35, 5.14), self-stigma (AOR = 3.62; 95% CI = 1.19, 11.02), and smartphone addiction (AOR = 1.09, 95% CI = 1.001, 1.19) were risk factors, and trait resilience was a protective factor (AOR = 0.58; 95% CI = 0.29, 1.17) for PTSD. Conclusion: The findings demonstrated a high prevalence of insomnia and PTSD. Risk-reducing strategies and protective factor promotion strategies are recommended to help reduce the symptoms of insomnia and PTSD among Taiwan frontline government workers.

5.
Front Psychiatry ; 13: 899040, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757229

RESUMO

Objective: We aimed to investigate the efficacy and tolerability of cranial electrotherapy stimulation (CES) for patients with anxiety symptoms. Method: We searched the Pubmed, Cochrane Central Register of Controlled Trials (CENTRAL), Embase and Medline for randomized control trials (RCTs) from the time of inception until November 15, 2021, following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Data were pooled using a random-effects model. The primary outcomes were the mean change scores for anxiety symptoms. The secondary outcomes were the mean change scores for depressive symptoms. Results: Eleven RCTs were eligible (n = 794, mean age: 41.4, mean population of female: 64.8%). CES significantly reduced the anxiety symptoms compared to the control group [k = 11, n = 692, Hedge's g = -0.625, 95% confidence intervals (CIs) = -0.952 to -0.298, P < 0.001] with moderate effect size. The subgroup analysis showed that CES reduced both primary and secondary anxiety (primary anxiety, k =3, n = 288, Hedges' g = -1.218, 95% CIs = -1.418 to -0.968, P = 0.007; secondary anxiety, k = 8, n = 504, Hedges' g = -0.334, 95% CIs = -0.570 to -0.098, P = 0.006). After performing between group analysis, we found CES has significant better efficacy for patients with primary anxiety than those with secondary anxiety (P < 0.001). For secondary outcome, CES significantly reduced depressive symptoms in patients with anxiety disorders (k = 8, n = 552, Hedges' g = -0.648, 95% CIs = -1.062 to -0.234, P = 0.002). No severe side effects were reported and the most commonly reported adverse events were ear discomfort and ear pain. Conclusion: We found CES is effective in reducing anxiety symptoms with moderate effect size in patients with both primary and secondary anxiety. Furthermore, CES was well-tolerated and acceptable.Systematic Review Registration: PROSPERO, https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021267916.

6.
Front Psychiatry ; 13: 884390, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35599760

RESUMO

Objective: This study aimed to investigate the efficacy of repetitive transcranial magnetic stimulation (rTMS) in treating suicidal ideation in patients with mental illness. Method: We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Major electronic databases were systematically searched from the time of their inception until July 22, 2021. The primary outcome was the mean change in the scores for suicidal ideation. The secondary outcome was the mean change in depression severity. Results: Ten randomized controlled trials were eligible with 415 participants in the active treatment group (mean age = 53.78 years; mean proportion of women = 54.5%) and 387 participants in the control group (mean age = 55.52 years; mean proportion of women = 51.78%). rTMS significantly reduced suicidal ideation (k = 10, n = 802, Hedges' g = -0.390, 95% confidence interval [CI] = -0.193 to -0.588, p <.001) and severity of depressive symptoms (k = 9, n = 761, Hedges' g = -0.698, 95% CI = -1.023 to -0.372, p < 0.001) in patients with major mental disorders. In the subgroup analysis, rTMS reduced suicidal ideation among patients with non-treatment-resistant depression (non-TRD) (-0.208) but not in those with TRD. rTMS as combination therapy had a larger effect than did monotherapy (-0.500 vs. -0.210). Suicidal ideation significantly reduced in patients receiving more than ten treatment sessions (-0.255). Importantly, the rTMS group showed favorable tolerability without major adverse events. Conclusion: The study showed that rTMS was effective and well-tolerated in reducing suicidal ideation and depression severity in patients with major mental disorders.

7.
J Affect Disord ; 306: 182-189, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35331821

RESUMO

OBJECTIVE: To date, there is limited evidence on the antidepressant effects of memantine in patients with major mental diseases. We conducted a systematic review and meta-analysis to assess the efficacy of memantine in such populations. METHODS: A literature search was performed for randomized controlled trials (RCTs) from the date of their inception until September 28, 2021, using PubMed, Medline, Embase, and the Cochrane Library. Changes in depression scores were the primary outcome. The response rate and remission rate to the treatment were secondary outcomes. We also assessed the dropout rate for tolerance. RESULTS: Eleven double-blind RCTs were included with 899 participants. Memantine significantly reduced depressive symptom scores compared with the control group (k = 11, n = 899, Hedges' g = -0.17, 95% confidence interval [CI] = -0.30 to -0.04, p = 0.009) with a small effect size. For secondary outcomes, memantine did not show a significant effect on response rate nor remission rate. In the subgroup analysis, memantine significantly reduced depressive symptom scores in patients with mood disorders (k = 8, n = 673, Hedges' g = -0.17, 95% CI = -0.32 to -0.01, p = 0.035) with a small effect size, but not in patients with schizophrenia. CONCLUSION: The present meta-analysis indicates that memantine effectively alleviates depressive symptoms in patients with mood disorders with a small effect size. Furthermore, memantine is well-tolerated and acceptable.


Assuntos
Memantina , Transtornos Psicóticos , Antidepressivos/uso terapêutico , Depressão , Humanos , Memantina/efeitos adversos , Transtornos Psicóticos/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Nanomaterials (Basel) ; 12(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35269279

RESUMO

Ordered mesoporous Santa Barbara amorphous (SBA-15) materials have high surface areas and are widely used in adsorption, separation, filtration, and heterogeneous catalytic processes. However, SBA-15 surfaces contain hydroxyl groups that are unsuited to the adsorption of organic pollutants; thus, SBA-15 must be chemically modified to promote its adsorption activity. In this study, amino-functionalized nanoporous SBA-15 was fabricated by employing sodium silicate as a precursor. The structural characteristics of the prepared composites were examined using thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectrometry, field-emission scanning electron microscopy, transmission electron microscopy, and surface area analysis. The prepared SBA-15 had a large pore size (6.46-7.60 nm), large pore volume (1.037-1.105 cm3/g), and high surface area (546-766 m2/g). Functionalization caused a reduction in the SBA-15 pore volume and surface area, whereas amino groups that promoted an interaction between adsorbates and solids facilitated solute adsorption. The adsorption of tannic acid (TA) onto amino-modified silica composites (SBA-15 and 3-aminopropyltriethoxysilane (SBA-15/APTES) and SBA-15 and pentaethylenehexamine (SBA-15/PEHA)) was studied. Their adsorption capacities were affected by solution temperature, solution pH, agitation speed, adsorbent dosage, and initial TA concentration. The maximum adsorption capacities for SBA-15/APTES and SBA-15/PEHA were 485.18 and 413.33 mg/g, respectively, with SBA-15/APTES exhibiting ultrafast removal of TA (98.61% removal rate at 15 min). In addition, this study explored the thermodynamics, adsorption isotherms, and kinetics. A comparison of two types of amino-functionalized SBA-15 was used for the first time to adsorb TA, which providing valuable information on TA adsorption on high adsorption capacity materials in water media.

9.
Front Public Health ; 9: 777255, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34957028

RESUMO

In response to the COVID-19 pandemic, Taiwan has been one of the best performers in the world with extremely low infections and deaths. This success can be attributed to the long experiences dealing with natural disasters and communicable diseases. However, with different disastrous characteristics, the disaster management systems for communicable diseases and natural disasters are very different in terms of laws, plans, frameworks, and emergency operations. Taking the response to COVID-19 pandemic as a study subject, we found that disaster management for communicable diseases can be improved through a comparison with natural disasters, and vice versa. First, having wider and longer impacts than natural disasters, the plans and framework for communicable diseases in Taiwan focus more on national and regional scales. Local governments would need more capacity support including budgets and training to conduct investigations and quarantine during the COVID-19 pandemic. Second, for quick response, the emergency operation for communicable diseases was designed to be more flexible than that for natural disasters by giving the commander more authority to adjust to the circumstances. The commanding system requires a more objective consultation group to prevent arbitrary decisions against the COVID-19 pandemic. Finally, risk governance is important for communicable diseases as well as for natural disasters. Additional efforts should be made to enhance vulnerability assessment, disaster reduction, and risk communication for shaping responses and policies in an efficient and coordinating way.


Assuntos
COVID-19 , Desastres Naturais , Humanos , Pandemias/prevenção & controle , SARS-CoV-2 , Taiwan/epidemiologia
10.
ACS Omega ; 6(3): 2052-2059, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33521444

RESUMO

Identifying and quantifying chromium in water are important for the protection of precious water resources from chromium pollution. Standard methods however are unable to easily distinguish toxic hexavalent chromium, Cr(VI), from innocuous trivalent chromium, Cr(III), are time-consuming, or require large sample quantity. We show in this report that Cr(VI) and Cr(III) in water can be differentiated based on their distinct spectral features of surface-enhanced Raman scattering (SERS). Their SERS signals exhibit different pH dependences: the SERS features of Cr(VI) and Cr(III) are most prominent at pH values of 10 and 5.5, respectively. The obtained limit of detection of Cr(VI) in water is below 0.1 mg/L. Both concentration curves of their SERS signals show Langmuir sorption isotherm behavior. A procedure was developed to quantify Cr(VI) concentration based on the direct retrieval or addition method with an error of 10%. Finally, the SERS detection of Cr(VI) is shown to be insensitive to co-present Cr(III). The developed SERS procedure offers potential to monitor toxic chromium in fields.

11.
Nutrients ; 14(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35010945

RESUMO

Macrophage polarization plays essential and diverse roles in most diseases, such as atherosclerosis, adipose tissue inflammation, and insulin resistance. Homeostasis dysfunction in M1/M2 macrophage polarization causes pathological conditions and inflammation. Neuroinflammation is characterized by microglial activation and the concomitant production of pro-inflammatory cytokines, leading to numerous neurodegenerative diseases and psychiatric disorders. Decreased neuroinflammation can be obtained by using natural compounds, including flavonoids, which are known to ameliorate inflammatory responses. Among flavonoids, quercetin possesses multiple pharmacological applications and regulates several biological activities. In the present study, we found that quercetin effectively inhibited the expression of lipocalin-2 in both macrophages and microglial cells stimulated by lipopolysaccharides (LPS). The production of nitric oxide (NO) and expression levels of the pro-inflammatory cytokines, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, were also attenuated by quercetin treatment. Our results also showed that quercetin significantly reduced the expression levels of the M1 markers, such as interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1ß, in the macrophages and microglia. The M1 polarization-associated chemokines, C-C motif chemokine ligand (CCL)-2 and C-X-C motif chemokine ligand (CXCL)-10, were also effectively reduced by the quercetin treatment. In addition, quercetin markedly reduced the production of various reactive oxygen species (ROS) in the microglia. The microglial phagocytic ability induced by the LPS was also effectively reduced by the quercetin treatment. Importantly, the quercetin increased the expression levels of the M2 marker, IL-10, and the endogenous antioxidants, heme oxygenase (HO)-1, glutamate-cysteine ligase catalytic subunit (GCLC), glutamate-cysteine ligase modifier subunit (GCLM), and NAD(P)H quinone oxidoreductase-1 (NQO1). The enhancement of the M2 markers and endogenous antioxidants by quercetin was activated by the AMP-activated protein kinase (AMPK) and Akt signaling pathways. Together, our study reported that the quercetin inhibited the effects of M1 polarization, including neuroinflammatory responses, ROS production, and phagocytosis. Moreover, the quercetin enhanced the M2 macrophage polarization and endogenous antioxidant expression in both macrophages and microglia. Our findings provide valuable information that quercetin may act as a potential drug for the treatment of diseases related to inflammatory disorders in the central nervous system.


Assuntos
Antioxidantes/farmacologia , Polaridade Celular/efeitos dos fármacos , Macrófagos/metabolismo , Microglia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quercetina/farmacologia , Animais , Polaridade Celular/fisiologia , Ciclo-Oxigenase 2/metabolismo , Heme Oxigenase-1/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Ativação de Macrófagos , Camundongos , Microglia/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
12.
Sensors (Basel) ; 20(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371509

RESUMO

The focus of this paper was designing and demonstrating bus structure FBG sensor networks using intensity wavelength division multiplexing (IWDM) techniques and a gated recurrent unit (GRU) algorithm to increase the capability of multiplexing and the ability to detect Bragg wavelengths with greater accuracy. Several Fiber Bragg grating (FBG) sensors are coupled with power ratios of 90:10 and 80:10, respectively in the suggested experimental setup. We used the latest IWDM multiplexing technique for the proposed scheme, as the IWDM system increases the number of sensors and allows us to alleviate the limited operational region drawback of conventional wavelength division multiplexing (WDM). However, IWDM has a crosstalk problem that causes high-sensor signal measurement errors. Thus, we proposed the GRU model to overcome this crosstalk or overlapping problem by converting the spectral detection problem into a regression problem and considered the sequence of spectral features as input. By feeding this sequential spectrum dataset into the GRU model, we trained the GRU system until we achieved optimal efficiency. Consequently, the well-trained GRU model quickly and accurately identifies the Bragg wavelength of each FBG from the overlapping spectra. The Bragg wavelength detection performance of our proposed GRU model is tested or validated using different numbers of FBG sensors, such as 3-FBG, 5-FBG, 7-FBG, and 10-FBG, separately. As a result, the experiment result proves that the well-trained GRU model accurately identifies each FBG Bragg wavelength, and even the number of FBG sensors increase, as well as the spectra of FBGs, which are partially or fully overlapped. Therefore, to boost the detection efficiency, reliability, and to increase the multiplexing capabilities of FBG sensor networks, the proposed sensor system is better than the other previously proposed methods.

13.
Sci Total Environ ; 745: 140794, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32731064

RESUMO

The aquatic sediment acts as a reservoir for multiple sources of pollutants including toxic metals. Most analytical methods used for estimating the bioavailability of sediment heavy metals have not been biologically validated by correlation with an aquatic organism's response. A reliable whole-sediment contacting toxicity assay using vertebrate species is lacking and the exposure routes for sediment metals are unclear. This study established a novel bio-analytical approach involving the Chelex-100 resin detection system and sediment toxicity assessment with embryo-larval stages of medaka fish (Oryzias latipes) to evaluate the bioavailability and toxicity of lead (Pb) contamination in sediment to fish. Treated fish exposed to the Pb-spiked artificial sediment with whole-sediment exposure showed more dose-dependent toxic responses than those from pore- or overlying-water exposure extracted from the same sediment. The Chelex-100 resin-extractable Pb content was highly correlated with mortality, total malformation and Pb bioaccumulation in medaka embryos or hatchlings from Pb-spiked sediment at environmentally relevant concentrations. The environmental sediment with higher contents of clay or organic carbon showed lower potency of releasing Pb from sediment to overlying water, as compared to those observed with artificial sediment. Our results suggest that the bio-analytical method can be practically applied in situ to evaluate the adverse effect of heavy metal-contaminated sediment on the aquatic ecosystem.


Assuntos
Metais Pesados , Oryzias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Disponibilidade Biológica , Ecossistema , Sedimentos Geológicos , Chumbo/toxicidade , Poliestirenos , Polivinil
14.
J Biomed Mater Res A ; 76(3): 463-9, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16315188

RESUMO

The aim of this study was to evaluate peripheral nerve regeneration across a 15-mm gap in the sciatic nerve of the rat, using a silicone rubber nerve guide filled with different concentrations of astragaloside (0, 50, 100, and 200 microM). Collagen was also filled in the chambers to prevent the astragaloside from leakage. At the end of 8 weeks, animals from the group treated with astragaloside, especially at the concentration of 50 microM, had a higher rate of successful regeneration across the wide gap, a significantly larger number of myelinated axons, and a greater evoked action potential than the control group. However, the high-dose astragaloside (200 microM) completely reversed this positive effect of growth-promoting capability and inhibited nerve regeneration. Thus, astragaloside plays a dual role in anastomosis, being salutary in aiding the growth of axons in peripheral nerve but also detrimental, terminating the nerve regenerative processes if improperly applied.


Assuntos
Axônios/fisiologia , Regeneração/efeitos dos fármacos , Saponinas/farmacologia , Nervo Isquiático/fisiologia , Triterpenos/farmacologia , Animais , Relação Dose-Resposta a Droga , Ratos , Ratos Sprague-Dawley , Regeneração/fisiologia , Nervo Isquiático/citologia
15.
Am J Chin Med ; 33(5): 767-78, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16265989

RESUMO

The electrical stimulation of meridian points in rats inhibits the withdrawal reflex of the nociceptive tail. Its pain mechanisms are well-documented. Moreover, electroacupuncture (EA) at special abdominal acupoints has been shown to induce a short-term hypoglycemia effect in streptozotocin diabetic rats. The Zusanli and Zhongwan acupoints have been widely used in traditional Chinese medicine to relieve symptoms of diabetes mellitus. It is still unclear whether they can affect extracellular glucose and lactate metabolites at the cellular level. The aim of this study is to evaluate these effects using a rat model for the analysis of extracellular neurochemicals. First, electrical stimulus of 2 ms 2 Hz square pulses (30 minutes) was applied to anesthetized intact rats (n = 7) at the Zusanli points. One and a half hours later, a second electrical stimulus (2 Hz pulses, 30 minutes) was delivered to two of the rats at the same spot. Another two rats received a different stimulation (100 Hz pulses, 30 minutes) at the same location. In the final three rats, a second electrical stimulus of 2 Hz pulses was delivered to non-acupoints. An automated micro-blood sample collector was used to examine the glucose, pyruvate and lactate concentrations. The EA signal has an influence on the biologic process of energy metabolism by mediating dynamic extracellular neurochemical changes. The EA at limb acupoints of the lower limbs induces a decrease in glucose, an increase in lactate metabolites and a decrease in the lactate/glucose ratio. Moreover, the increased lactate/glucose ratio suggests that the cell has an increased anaerobic glucose metabolism.


Assuntos
Glicemia/análise , Eletroacupuntura , Metabolismo Energético/fisiologia , Ácido Láctico/sangue , Ácido Pirúvico/sangue , Pontos de Acupuntura , Animais , Meridianos , Ratos , Ratos Sprague-Dawley
16.
Nutr Cancer ; 48(2): 189-97, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15231454

RESUMO

Antrodia camphorata (A. camphorata) is well known in Taiwan as a traditional Chinese medicine, and it has been shown to exhibit antioxidant effects. In this study, the ability of A. camphorata to induce apoptosis was studied in cultured human premyelocytic leukemia HL-60 cells. Treatment of the HL-60 cells with a variety of concentrations of the fermented culture broth of A. camphorata (25-150 microg/ml) resulted in dose- and time-dependent sequences of events marked by apoptosis, as shown by loss of cell viability, chromatin condensation, and internucleosomal DNA fragmentation. Furthermore, apoptosis in the HL-60 cells was accompanied by the release of cytochrome c, activation of caspase-3, and specific proteolytic cleavage of poly (ADP-ribose) polymerase (PARP). This increase in A. camphorata-induced apoptosis was also associated with a reduction in the levels of Bcl-2, a potent cell-death inhibitor, and an increase in those of the Bax protein, which heterodimerizes with and thereby inhibits Bcl-2. The data suggest that A. camphorata exerts antiproliferative action and growth inhibition on HL-60 cells through apoptosis induction and that it may have anticancer properties valuable for application in drug products.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Polyporaceae/química , Caspase 3 , Caspases/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Genes bcl-2/efeitos dos fármacos , Células HL-60 , Humanos , Marcação In Situ das Extremidades Cortadas , Cinética
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