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1.
Front Surg ; 11: 1368493, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533091

RESUMO

Objective: Chronic hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH) results in poor neurological outcomes and cognitive deficits. Currently, the main treatments for chronic hydrocephalus include ventriculoperitoneal shunt (VPS) and lumboperitoneal shunt (LPS); however, the optimal treatment for chronic hydrocephalus after aSAH remains controversial. Method: The records of 82 patients were retrospectively analyzed, and the patients were divided into VPS and LPS groups based on surgical methods. The efficacy, shunt successful rate and complications were compared. The assessments of treatment efficacy included the Evans index score (EIS), Keifer's hydrocephalus score (KHS), Mini-Mental State Examination (MMSE) score and functional independence measure (FIM). Patients were followed up for three months to observe the postoperative curative effects and complications. Results: The rate of shunt obstruction was significantly higher in the LPS group than that in the VPS group (p < 0.05), and the shunt successful rate was significantly higher in the VPS group than that in the LPS group (p < 0.05). The total rate of complications was 24.4% for LPS and 39% for VPS. The improvements in EIS, KHS, MMSE, and FIM within each group after the shunt were significantly different compared to those before shunt (p < 0.05). Compared to those in the LPS group, the improvements in EIS, KHS, MMSE, and FIM were significantly different in the VPS group after shunt (p < 0.05). Conclusion: Compared with LPS, VPS in the treatment for chronic hydrocephalus after aSAH had greater therapeutic efficacy, as indicated by improved radiological outcomes, improved shunt successful rate, improved clinical outcomes, and improved quality of life. Therefore, we believe that VPS is the preferred treatment option for chronic hydrocephalus after aSAH, while LPS should only be used as an alternative to VPS.

2.
BMC Surg ; 24(1): 10, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172767

RESUMO

BACKGROUND: Increased intracranial pressure (ICP) in patients with hypertensive intracerebral hemorrhage (HICH) has been associated with poor prognosis. The transsylvian insular approach (TIA) and the transcortical (TCA) approach are applied for patients with HICH. We aimed to compare the postoperative ICP parameters of TIA and TCA to identify which procedure yields better short-term outcomes in patients with basal ganglia hematoma volumes ranging from 30 to 50 mL. METHODS: Eighty patients with basal ganglia hematomas 30-50 mL were enrolled in this study. Patients were implanted with ICP probes and divided into TIA and TCA groups according to the procedure. The ICP values were continuously recorded for five days at four-hour intervals. Short-term outcomes were evaluated using the length of hospitalization and postoperative consciousness recovery time. RESULTS: No statistically significant differences were found in age, sex, GCS score at admission, hematoma volume, and hematoma clearance rate (p > 0.05). The results showed that postoperative initial ICP, ICP on the first postoperative day, mean ICP, DICP20 mmHg × 4 h, postoperative consciousness recovery time, the length of hospitalization, mannitol utilization rate and the mannitol dosage were lower in the TIA group than in the TCA group (p < 0.05). Postoperative consciousness recovery time was positively correlated with ICP on the first postoperative day, and the length of hospitalization was positively correlated with mean ICP. CONCLUSIONS: TIA is more effective than TCA in improving the short-term outcomes of patients with basal ganglia hematoma volumes ranging from 30 to 50 mL according to comparisons of postoperative ICP parameters.


Assuntos
Hemorragia Intracraniana Hipertensiva , Humanos , Hemorragia Intracraniana Hipertensiva/cirurgia , Pressão Intracraniana , Resultado do Tratamento , Manitol , Hematoma/cirurgia
3.
Sci Bull (Beijing) ; 68(24): 3240-3251, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37980171

RESUMO

Reducing soil salinization of croplands with optimized irrigation and water management is essential to achieve land degradation neutralization (LDN). The effectiveness and sustainability of various irrigation and water management measures to reduce basin-scale salinization remain uncertain. Here we used remote sensing to estimate the soil salinity of arid croplands from 1984 to 2021. We then use Bayesian network analysis to compare the spatial-temporal response of salinity to water management, including various irrigation and drainage methods, in ten large arid river basins: Nile, Tigris-Euphrates, Indus, Tarim, Amu, Ili, Syr, Junggar, Colorado, and San Joaquin. In basins at more advanced phases of development, managers implemented drip and groundwater irrigation and thus effectively controlled salinity by lowering groundwater levels. For the remaining basins using conventional flood irrigation, economic development and policies are crucial for establishing a virtuous circle of "improving irrigation systems, reducing salinity, and increasing agricultural incomes" which is necessary to achieve LDN.

4.
Sci Data ; 10(1): 587, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679357

RESUMO

Simulating the carbon-water fluxes at more widely distributed meteorological stations based on the sparsely and unevenly distributed eddy covariance flux stations is needed to accurately understand the carbon-water cycle of terrestrial ecosystems. We established a new framework consisting of machine learning, determination coefficient (R2), Euclidean distance, and remote sensing (RS), to simulate the daily net ecosystem carbon dioxide exchange (NEE) and water flux (WF) of the Eurasian meteorological stations using a random forest model or/and RS. The daily NEE and WF datasets with RS-based information (NEE-RS and WF-RS) for 3774 and 4427 meteorological stations during 2002-2020 were produced, respectively. And the daily NEE and WF datasets without RS-based information (NEE-WRS and WF-WRS) for 4667 and 6763 meteorological stations during 1983-2018 were generated, respectively. For each meteorological station, the carbon-water fluxes meet accuracy requirements and have quasi-observational properties. These four carbon-water flux datasets have great potential to improve the assessments of the ecosystem carbon-water dynamics.

5.
Glob Chang Biol ; 29(2): 547-562, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36222783

RESUMO

Agricultural activities have been expanding globally with the pressure to provide food security to the earth's growing population. These agricultural activities have profoundly impacted soil organic carbon (SOC) stocks in global drylands. However, the effects of clearing natural ecosystems for cropland (CNEC) on SOC are uncertain. To improve our understanding of carbon emissions and sequestration under different land uses, it is necessary to characterize the response patterns of SOC stocks to different types of CNEC. We conducted a meta-analysis with mixed-effect model based on 873 paired observations of SOC in croplands and adjacent natural ecosystems from 159 individual studies in global drylands. Our results indicate that CNEC significantly (p < .05) affects SOC stocks, resulting from a combination of natural land clearing, cropland management practices (fertilizer application, crop species, cultivation duration) and the significant negative effects of initial SOC stocks. Increases in SOC stocks (in 1 m depth) were found in croplands which previously natural land (deserts and shrublands) had low SOC stocks, and the increases were 278.86% (95% confidence interval, 196.43%-361.29%) and 45.38% (26.53%-62.23%), respectively. In contrast, SOC stocks (in 1 m depth) decreased by 24.11% (18.38%-29.85%) and 10.70% (1.80%-19.59%) in clearing forests and grasslands for cropland, respectively. We also established the general response curves of SOC stocks change to increasing cultivation duration, which is crucial for accurately estimating regional carbon dynamics following CNEC. SOC stocks increased significantly (p < .05) with high long-term fertilizer consumption in cleared grasslands with low initial SOC stocks (about 27.2 Mg ha-1 ). The results derived from our meta-analysis could be used for refining the estimation of dryland carbon dynamics and developing SOC sequestration strategies to achieve the removal of CO2 from the atmosphere.


Assuntos
Carbono , Solo , Ecossistema , Produtos Agrícolas , Agricultura/métodos , Sequestro de Carbono , Fertilizantes
6.
Eur Geriatr Med ; 13(6): 1327-1333, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36327046

RESUMO

PURPOSE: Although physical exercise may improve memory in older adults, whether the Chinese traditional fitness exercise Wuqinxi improves working memory and delays cognitive deterioration in older adults with mild cognitive impairment (MCI) has not been assessed in randomized controlled experiments. METHODS: Fifty older adults with MCI based on their Montreal Cognitive Assessment scores were randomized to either a Wuqinxi exercise group or a non-exercise control group. The exercise group engaged in Wuqinxi once a week for 60 min each session for 40 weeks. Participants in the control group received no intervention and maintained their regular living habits. The n-back paradigm was used to measure changes in working memory before and after Wuqinxi exercise. RESULTS: In the 0-back task, the response speed of older adults with MCI who participated in Wuqinxi was faster than that of older adults with MCI in the non-exercise control group (P = 0.031); there was no significant difference in accuracy between the two groups (P > 0.05). In the 1-back and 2-back tasks, there was no significant difference in response times or in accuracy between the two groups (P > 0.05). CONCLUSIONS: In this randomized controlled study, participation in long-term Wuqinxi delayed the deterioration of working memory in older adults with MCI, suggesting that this exercise may be an effective intervention to delay or prevent the progression of MCI to Alzheimer's disease.


Assuntos
Disfunção Cognitiva , Memória de Curto Prazo , Humanos , Idoso , Memória de Curto Prazo/fisiologia , Disfunção Cognitiva/terapia , Exercício Físico/fisiologia , Modalidades de Fisioterapia
7.
J Environ Manage ; 314: 115078, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35447452

RESUMO

The transboundary Aral Sea Basin (ASB) covers parts of the former Union of Soviet Socialist Republics (USSR), the central Asian portion of Kazakhstan (KAZ), Uzbekistan (UZB), Turkmenistan (TUK), Kyrgyzstan (KGZ), and Tajikistan (TAJ). During recent decades, the region has experienced widespread cropland changes and has therefore attracted attention. However, carbon flux caused by these changes, which is critical to understand the carbon cycle in the region and to develop strategies for carbon sequestration, has not been quantified. We applied the Bookkeeping Model to analyze carbon flux caused by cropland changes. We found that the cropland area expanded from 1975 to 2019. Prior to 1990, the net increment in cropland area was 64.47 kha yr-1; this decreased to 11.02-18.69 kha yr-1 after the collapse of the USSR (1991). Grasslands and bare lands with low carbon density were the main types of land that were converted to cropland, accounting for approximately 70.3-99.29% of the land cleared for cropland. In terms of cropland loss, grassland accounted for more than 40.69% of the cropland converted to other land cover types, followed by artificial surfaces, which accounted for 25.84-45.16%. The expansion of cropland served as a carbon sink owing to the increase in irrigation and fertilization. The overall potential carbon emission was -89.38 ± 35.34 Tg C, and contributions of the five countries were as follows: TUR (-33.65 ± 6.30 Tg C), UZB (-29.23 ± 25.35 Tg C), KAZ (-12.76 ± 12.16 Tg C), TAJ (-11.11 ± 5.47 Tg C), KGZ (-2.63 ± 7.83 Tg C). The net carbon flux was -2.04 ± 0.23 Tg C yr-1 before 1990, and it decreased to -1.87 ± 1.03 Tg C yr-1 during the post-Soviet era. Finally, we state sustainable agricultural management is urgently needed to deal with the environmental problems of the Aral Sea, which have been primarily caused by cropland expansion.


Assuntos
Sequestro de Carbono , Produtos Agrícolas , Agricultura , Carbono , Ciclo do Carbono
8.
IEEE Trans Cybern ; 52(6): 4661-4674, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33259313

RESUMO

In this article, we present a semantic semisupervised learning (Semantic SSL) approach targeted at unifying two machine-learning paradigms in a mutually beneficial way, where the classical support vector machine (SVM) learns to reveal primitive logic facts from data, while axiomatic fuzzy set (AFS) theory is utilized to exploit semantic knowledge and correct the wrongly perceived facts for improving the machine-learning model. This novel semisupervised method can easily produce interpretable semantic descriptions to outline different categories by forming a fuzzy set with semantic explanations realized on the basis of the AFS theory. Besides, it is known that disagreement-based semisupervised learning (SSL) can be viewed as an excellent schema so that a co-training approach with SVM and the AFS theory can be utilized to improve the resulting learning performance. Furthermore, an evaluation index is used to prune descriptions to deliver promising performance. Compared with other semisupervised approaches, the proposed approach can build a structure to reflect data-distributed information with unlabeled data and labeled data, so that the hidden information embedded in both labeled and unlabeled data can be sufficiently utilized and can potentially be applied to achieve good descriptions of each category. Experimental results demonstrate that this approach can offer a concise, comprehensible, and precise SSL frame, which strikes a balance between the interpretability and the accuracy.


Assuntos
Algoritmos , Máquina de Vetores de Suporte , Aprendizagem , Semântica , Aprendizado de Máquina Supervisionado
9.
Opt Express ; 28(20): 29245-29252, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114828

RESUMO

In this paper, high-performance 1×128 linear arrays of 4H-SiC ultraviolet (UV) avalanche photodiode (APD) with dual-frequency plasma enhanced chemical vapor deposition (PECVD) passivation are demonstrated for the first time. The results show that SiNx dielectric deposited by dual-frequency PECVD can effectively reduce the leakage current at high bias voltages. Due to the improved 4H-SiC epi-layer material and SiNx passivation, the fabricated 22 mm-long 1×128 4H-SiC APD linear arrays exhibit an excellent performance with a high pixel yield of 100% and a small breakdown voltage variation of 0.2 V, which is the best result ever reported. At room temperature, the pixels have a gain of over 105 and a maximum quantum efficiency of 53.5% @ 285 nm. Besides the high uniformity of breakdown voltage for 128 pixels, the dark currents at 95% of breakdown voltage are all below 1 nA.

10.
BMC Neurol ; 19(1): 341, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881866

RESUMO

BACKGROUND: To evaluate the efficacy of microvascular decompression (MVD) in reducing hypertension (HTN) in hypertensive patients with trigeminal neuralgia (TN). METHODS: The clinical data of 58 cases of neurogenic HTN with TN treated in our hospital were retrospectively reviewed. Preoperative MR revealed abnormal blood pressure in the left rostral ventrolateral medulla (RVLM) and the posterior cranial nerve root entry zone (REZ). The patients were divided into control group: only trigeminal nerve was treated with MVD; experimental group: trigeminal nerve, RVLM and REZ were treated with MVD at the same time. The patients were followed up for 6 months to 1 year to observe the changes of blood pressure. RESULTS: There was no significant difference in gender, age, course of TN, course of HTN, grade of HTN and preoperative blood pressure between the two groups. After operation, the effective rate of HTN improvement with MVD was 32.1% in the control group. There was no significant difference in the preoperative and post operative blood pressure. (P△SBP = 0.131; P△BDP = 0.078). In the experimental group, the effective rate was 83.3%. The postoperative blood pressure was significantly lower than preoperative values. (P△SBP < 0.001; P△DBP < 0.001). CONCLUSIONS: MVD is an effective treatment for neurogenic HTN. However, the criteria for selecting hypertensive patients who need MVD to control their HTN still needs to be further determined. Possible indications may include: left trigeminal neuralgia, neurogenic HTN; abnormal blood pressure compression in the left RVLM and REZ areas on MR; and blood pressure in these patients can not be effectively controlled by drugs.


Assuntos
Hipertensão/etiologia , Hipertensão/cirurgia , Bulbo/cirurgia , Cirurgia de Descompressão Microvascular/métodos , Doenças Vasculares/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Bulbo/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/cirurgia , Doenças Vasculares/complicações
11.
PeerJ ; 7: e7693, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31579594

RESUMO

BACKGROUND: The control of an upright stance in humans is important in medicine, psychology, and physiology. The maintenance of upright stance balance depends not only on sensory information from proprioceptive, vestibular, cutaneous, and visual sources but also on cognitive resources. The present study investigated the effects of cognitive tasks while standing with eyes open on upright stance balance in adolescents. We hypothesized that performing a cognitive task while standing with eyes open would increase body sway among these adolescents and that the upright posture would thus become less stable. METHODS: A static balance assessment system comprising a force platform connected to a computer was used to evaluate the stability of the upright stance among 21 healthy adolescents under six conditions: no cognitive task, a relatively easy cognitive task, or the same cognitive task made more difficult, with each task being performed while the eyes were open and again while the eyes were closed. The participants performed mental calculations as fast as possible by subtracting either 3 or 18 from a random three-digit number continuously, for the simple cognitive task or the difficult cognitive task, respectively. Each calculation was completed within 10 s. The evaluation indexes used to measure upright posture stability were the root mean square (RMS) of the total body sway in the mediolateral and anteroposterior directions, the mean velocity (MV) value of the total body sway, and the Romberg quotient (RQ) of these values. RESULTS: The RMS (p < 0.01) and MV (p < 0.01) values of the upright posture sway were lower when participants performed no cognitive task and their eyes were open than when their eyes were closed. When their eyes were open, compared with no cognitive task, the values of the measures evaluating upright posture sway were higher, meaning the stance was less stable, while performing either the simple or the more difficult cognitive task (RMS: simple task, p < 0.01; difficult task, p < 0.05; MV: simple task, p < 0.01; difficult task, p < 0.01) although no significant differences were detected for the RMS or MV values between the simple and more difficult cognitive tasks. The RQs for both the RMS and the total MV values of the upright posture sway during performance of the difficult cognitive task were significantly lower than when the participants performed no task. CONCLUSION: Performance of a cognitive task significantly reduced the upright posture balance in adolescents during eyes open although increased task difficulty did not show a greater effect. The interference between the performance of a cognitive task and the visual control of an upright stance may be attributable in part to cognitive and visual processing streams competing for common central resources, consistent with the Multiple Resource Theory of information processing.

12.
Mol Med Rep ; 19(1): 734-742, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30431124

RESUMO

MicroRNA­940 (miR­940) has been extensively studied in the pathogenesis of numerous types of human cancer; however, the expression pattern, roles and molecular mechanisms underlying the regulatory actions of miR­940 in glioma remain unknown. The present study aimed to further investigate miR­940 by studying its expression, roles and mechanisms of action in glioma. Reverse transcription­quantitative polymerase chain reaction (RT­qPCR) was used to detect miR­940 expression in glioma tissues and cell lines. The regulatory effects of miR­940 in glioma cell proliferation and invasion were determined using MTT and cell invasion assays. Bioinformatics analyses was performed to identify the potential target of miR­940, which was further confirmed by luciferase reporter assay, RT­qPCR and western blot analysis. In the present study, significantly increased miR­940 expression levels were observed in glioma tissues and cell lines compared with normal brain tissues and normal human astrocytes, respectively. Decreased miR­940 expression levels attenuated glioma cell proliferation and invasion in vitro. Kruppel­like factor 9 (KLF9) was predicted as a potential target of miR­940. Further assays demonstrated that miR­940 negatively regulated KLF9 expression in glioma cells by directly targeting the 3'­untranslated regions of KLF9. Additionally, KLF9 expression was downregulated in glioma tissues and was inversely correlated with miR­940. Furthermore, KLF9 knockdown was able to rescue the effects of miR­940 on glioma cell proliferation and invasion. The results of the present study suggest that miR­940 may function as an oncogene in glioma by targeting KLF9 and may be a considered a therapeutic target for the treatment of gliomas.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Fatores de Transcrição Kruppel-Like/metabolismo , MicroRNAs/genética , Idoso , Apoptose , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Movimento Celular , Feminino , Seguimentos , Glioma/genética , Glioma/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/genética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Células Tumorais Cultivadas
13.
Huan Jing Ke Xue ; 38(5): 1783-1791, 2017 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965081

RESUMO

In Beijing, the chemical composition and component concentrations of volatile organic compounds (VOCs) were investigated during the municipal solid waste composting process using a portable gas chromatograph coupled with a mass spectrometer. The contributions of VOCs to the ozone formation potential were computed using the maximum incremental reactivity (MIR) scale and the propylene-equivalent concentration scale. The results showed that the concentrations of waste discharge in the sorting room, the first fermentation workshop, the second fermentation workshop, the compost product workshop, and the plant boundary were 10302.1, 15484.1, 929.9, 4693.6 and 370.4 µg·m-3, respectively. The main VOCs of the municipal solid waste composting plant were ethanol, limonene, and acetone. The propylene-equivalent concentrations of waste discharge in the sorting room, the first fermentation workshop, the second fermentation workshop, the compost product workshop, and the plant boundary were 25875.7, 4087.9, 378.0, 747.7 and 296.8 µg·m-3, whereas the O3 formation potentials computed using the MIR scale were 26979.3, 21168.3, 1469.3, 6439.6 and 455.8 µg·m-3. Reducing pollution by controlling the VOCs emission of waste discharge in the sorting room and the first fermentation workshop is important and can decrease the ozone formation potential. Given the accuracy and accessibility of the method, the MIR scale is more suitable for calculating the ozone formation potential of VOCs emitted from the municipal solid waste composting plant.

14.
PLoS One ; 11(12): e0168422, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28005917

RESUMO

Cement is one of the mostly used construction materials due to its high durability and low cost, but it suffers from brittle fracture and facile crack initiation. This article describes the use of naturally-derived renewable cellulose nanofibers (CNFs) to reinforce cement. The effects of CNFs on the mechanical properties, degree of hydration (DOH), and microstructure of cement pastes have been studied. It is found that an addition of 0.15% by weight of CNFs leads to a 15% and 20% increase in the flexural and compressive strengths of cement paste. The enhancement in mechanical strength is attributed to high DOH and dense microstructure of cement pastes after adding CNFs.


Assuntos
Celulose/química , Cimentação/métodos , Materiais de Construção , Nanofibras/química , Conservação dos Recursos Naturais , Teste de Materiais
15.
Huan Jing Ke Xue ; 36(10): 3603-10, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26841591

RESUMO

Xining, Ningbo and Beijing were closen as the representative cities about biochemical treatment of kichen waste. The treatment facilities of these cities were investigated and set as the sampling points. The main compositions and the material contents were analyzed by GC/MS, the odor concertration was obtained by the Triangle odor bag method. The results showed that oxygenated hydrocarbons including alcohol, aldehyde, ketone, ester were higher than others in the odor gases, however, the largest contribution to odor pollution were sulfocompounds and the 2nd materials were terpenes; According to the research of the three enterprises, ethyl alcohol, limonene, sulfuretted hydrogen, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, acetaldehyde and ethyl acetate were likely to be considered as the typical odorants from the biochemical treatment facilities of kichen waste.


Assuntos
Resíduos de Alimentos , Gases/análise , Odorantes/análise , Eliminação de Resíduos/métodos , Acetaldeído , Pequim , China , Cidades , Etanol , Hidrocarbonetos , Sulfeto de Hidrogênio , Compostos de Sulfidrila , Sulfetos
16.
PLoS One ; 8(11): e81258, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24278406

RESUMO

Saponin 1 is a triterpeniod saponin extracted from Anemone taipaiensis, a traditional Chinese medicine against rheumatism and phlebitis. It has also been shown to exhibit significant anti-tumor activity against human leukemia (HL-60 cells) and human hepatocellular carcinoma (Hep-G2 cells). Herein we investigated the effect of saponin 1 in human glioblastoma multiforme (GBM) U251MG and U87MG cells. Saponin 1 induced significant growth inhibition in both glioblastoma cell lines, with a 50% inhibitory concentration at 24 h of 7.4 µg/ml in U251MG cells and 8.6 µg/ml in U87MG cells, respectively. Nuclear fluorescent staining and electron microscopy showed that saponin 1 caused characteristic apoptotic morphological changes in the GBM cell lines. Saponin 1-induced apoptosis was also verified by DNA ladder electrophoresis and flow cytometry. Additionally, immunocytochemistry and western blotting analyses revealed a time-dependent decrease in the expression and nuclear location of NF-κB following saponin 1 treatment. Western blotting data indicated a significant decreased expression of inhibitors of apoptosis (IAP) family members,(e.g., survivin and XIAP) by saponin 1. Moreover, saponin 1 caused a decrease in the Bcl-2/Bax ratio and initiated apoptosis by activating caspase-9 and caspase-3 in the GBM cell lines. These findings indicate that saponin 1 inhibits cell growth of GBM cells at least partially by inducing apoptosis and inhibiting survival signaling mediated by NF-κB. In addition, in vivo study also demonstrated an obvious inhibition of saponin 1 treatment on the tumor growth of U251MG and U87MG cells-produced xenograft tumors in nude mice. Given the minimal toxicities of saponin 1 in non-neoplastic astrocytes, our results suggest that saponin 1 exhibits significant in vitro and in vivo anti-tumor efficacy and merits further investigation as a potential therapeutic agent for GBM.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , NF-kappa B/metabolismo , Saponinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Células HL-60 , Células Hep G2 , Humanos , Espaço Intracelular/metabolismo , Camundongos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Transporte Proteico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Saponinas/administração & dosagem , Carga Tumoral/efeitos dos fármacos , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
17.
Int J Mol Med ; 32(5): 1077-84, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24048272

RESUMO

Glioblastoma multiforme (GBM) is one of the most common malignant brain tumors. Saponin B, a novel compound isolated from the medicinal plant, Anemone taipaiensis, has been found to have a strong time- and dose-dependent cytostatic effect on human glioma cells and to suppress the growth of U87MG GBM cells. In this study, we investigated whether saponin B induces the apoptosis of glioblastoma cells and examined the underlying mechanism(s) of action of saponin B. Saponin B significantly suppressed U87MG cell proliferation. Flow cytometric analysis of DNA in the U87MG cells confirmed that saponin B blocked the cell cycle at the S phase. Furthermore, treatment of the U87MG cells with saponin B induced chromatin condensation and led to the formation of apoptotic bodies, as observed under a fluorescence microscope, and Annexin V/PI assay further suggested that phosphatidylserine (PS) externalization was apparent at higher drug concentrations. Treatment with saponin B activated the receptor-mediated pathway of apoptosis, as western blot analysis revealed the activation of Fas-l. Saponin B increased the Bax and caspase-3 ratio and decreased the protein expression of Bcl-2. The results from the present study demonstrate that the novel compound, saponin B, effectively induces the apoptosis of GBM cells and inhibits glioma cell growth and survival. Therefore, saponin B may be a potential candidate for the development of novel cancer therapeutics with antitumor activity against gliomas.


Assuntos
Anemone/química , Antineoplásicos/farmacologia , Saponinas/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Saponinas/química
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