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1.
Inorg Chem ; 56(15): 9169-9176, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28737939

RESUMO

Tunable structures and magnetocaloric effect (MCE) of seven MOFs with [Gdn] as nodes are explored. The [Gdn] node is realized from mononuclear [Gd] to binuclear paddle-wheel [Gd2], tetranuclear tetrahedral [Gd4], and pentanuclear trigonal bipyramidal [Gd5]. Meanwhile, the magnetic entropy changes from 19.4 to 46.0 J·kg-1·K-1. The results reveal that the effect of magnetic density on MCE plays a dominant role for Gd3+-based compounds, and high spin ground state of Mn2+ (S = 5/2) is more favorable to achieve high MCE than that with Zn2+, Co2+, and Ni2+ (Co2+, S = 3/2; Ni2+, S = 1). To our knowledge, it is the first report that MCE is controlled by various clusters as nodes in MOFs.

2.
J Am Chem Soc ; 137(51): 15988-91, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26653619

RESUMO

Zeolites, as one of the most important porous materials, are most widely utilized in sorbents, catalysis, and ion-exchange fields. However, the multi-functional lanthanide-zeolites constructed exclusively by lanthanide ions and oxygen linkers are to our knowledge unknown hitherto. Herein, we, for the first time, report the unique structure and multifunctions of lanthanide zeolites (1·Gd, 1·Tb, 1·Dy), featuring 60 nuclear [Ln60] nanocages as building blocks and ultrastrong alkali-resisting. These compounds possess extremely high stability and still retain single crystallinity after treatment in boiling water, 0.1 M HCl, and 20 M NaOH aqueous solutions. Magnetic studies revealed 1·Gd has large magnetocaloric effect with -ΔSm(max) = 66.5 J kg(-1) K(-1), falling among the largest values known to date. Importantly, these lanthanide-zeolites themselves can efficiently catalyze the cycloaddition of CO2 with epoxides under mild conditions. Our finding extends the conventional zeolites to lanthanide counterparts, opening a new space for seeking novel and/or multifunctional zeolites.

3.
Adv Healthc Mater ; 13(5): e2302652, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37794560

RESUMO

Small frame nucleic acids (FNAs) serve as excellent carrier materials for various functional nucleic acid molecules, showcasing extensive potential applications in biomedicine development. The carrier module and function module combination is crucial for probe design, where an improper combination can significantly impede the functionality of sensing platforms. This study explores the effect of various combinations on the sensing performance of nanodevices through simulations and experimental approaches. Variances in response velocities, sensitivities, and cell uptake efficiencies across different structures are observed. Factors such as the number of functional molecules loaded, loading positions, and intermodular distances affect the rigidity and stability of the nanostructure. The findings reveal that the structures with full loads and moderate distances between modules have the lowest potential energy. Based on these insights, a multisignal detection platform that offers optimal sensitivity and response speed is developed. This research offers valuable insights for designing FNAs-based probes and presents a streamlined method for the conceptualization and optimization of DNA nanodevices.


Assuntos
MicroRNAs , Nanoestruturas , Ácidos Nucleicos , MicroRNAs/genética , DNA/química , Nanoestruturas/química , Simulação por Computador , Nanotecnologia/métodos
4.
Chemistry ; 18(47): 15086-91, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-23080423

RESUMO

Two 3D heterometal-organic frameworks based on infrequent trigonal bipyramidal Ln(5)  clusters as nodes were structurally and magnetically characterized (Ln=Gd (1), Dy (2)). The results indicate large MCE of up to 30.7 J kg(-1)  K(-1) in 1 and slow magnetic relaxation behavior in 2. Expectedly, constructing 3D MOFs based on multinuclear clusters as nodes may will be a new strategy for achieving large -ΔS(m). Additionally, compound 1 exhibits high thermal and solvent stabilities, providing a favorable foundation for realistic applications.

5.
J Natl Med Assoc ; 114(1): 47-55, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34973847

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a global health emergency. In addition to common respiratory symptoms, some patients with COVID-19 infections may experience a range of extra-pulmonary manifestations, such as digestive system involvement. Patients with COVID-19 have been reported to suffer from acute mesenteric ischemia (AMI) that is associated with disease-related severity and mortality. However, in the context of COVID-19, the exact cause of AMI has yet to be clearly defined. This review provides a comprehensive overview of the available data and elucidates the possible underlying mechanisms linking COVID-19 to AMI, in addition to highlighting therapeutic approaches for clinicians. Finally, given the severe global impact of COVID-19, we emphasize the importance of coordinated vaccination programs.


Assuntos
COVID-19 , Isquemia Mesentérica , COVID-19/complicações , Humanos , Pulmão , Isquemia Mesentérica/etiologia , Isquemia Mesentérica/terapia , Pandemias , SARS-CoV-2
6.
J Virol Methods ; 299: 114343, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34728269

RESUMO

Bovine respiratory disease complex (BRDC) is a serious disease affecting feedlot cattle in China and likely other places worldwide. Bovine viral diarrhea virus (BVDV) and bovine parainfluenza virus type 3 (BPIV3) are principally responsible for causing BRDC, and are a major strain to the industrial economy. Eradication of these viruses/disease requires swift viral identification and treatment. Hence, this study established a fast and easy procedure of BVDV and BPIV3 identification that employs reverse transcription recombinase polymerase amplification (RT-RPA) and lateral flow dipstick (LFD), and uses primers and lateral flow (LF) probe targeting the 5'-UTR gene of BVDV and phosphoprotein P gene of BPIV3, respectively. Our assay was able to successfully amplify BVDV and BPIV3 RNA within 25 min at 35 °C using RT-RPA, with products visible on the LFD within 5 min at room temperature (RT). The lowest detection limits were 50 RNA molecules for BVDV and 34 RNA molecules for BPIV3 per reaction. We also demonstrated that the established dual RT-RPA LFD assay was precise and targeted, harboring excellent potential to become an onsite molecular diagnostic tool in the detection of BVDV and BPIV3. This method can detect BVDV (Pestivirus A, B) and BPIV3, and exhibit no cross-reaction with other viruses like the classical swine fever virus (CSFV) and infectious bovine rhinotracheitis virus (IBRV). The assay performance was further assessed with clinical samples, and demonstrated good performance in comparison to real-time RT-PCR (RT-qPCR). Moreover, the RT-RPA LFD assay was comparitively rapid and required minimal training.


Assuntos
Recombinases , Transcrição Reversa , Animais , Bovinos , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Recombinases/genética , Sensibilidade e Especificidade , Suínos
7.
Hepatobiliary Pancreat Dis Int ; 10(4): 428-34, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21813394

RESUMO

BACKGROUND: Emerging evidence suggests that pancreatic adenocarcinoma is hierarchically organized and sustained by pancreatic cancer stem cells. Furthermore, elimination of these cells is possible and therapeutically relevant. This study aimed to investigate the expression patterns of pancreatic cancer stem cell surface markers CD44, CD24 and ESA in pancreatic adenocarcinoma cell lines and explore the influence of their local microenvironment. METHODS: Flow cytometry was used to analyze the expression patterns of CD44, CD24 and ESA in five pancreatic adenocarcinoma cell lines (PANC-1, PC-2, MIA-Paca-2, AsPC-1 and BxPC-3). In addition, the capacity for sphere-formation in serum-free medium of four cell lines (PANC-1, PC-2, MIA-Paca-2 and BxPC-3) was assessed. Then, the same assays were performed when tumor cell spheres were developed. The role of sonic hedgehog (SHH) in cell spheres from PANC-1 and MIA-Paca-2 were also assessed by RT-PCR. RESULTS: CD44 and CD24 were detected in PANC-1. Only CD44 expression was detected in PC-2, MIA-Paca-2 and AsPC-1. CD44, CD24 and ESA were all detected in BxPC-3. Tumor cell spheres developed in PANC-1 and MIA-Paca-2 in serum-free medium. This was accompanied by an increase in CD24 expression and a decrease in CD44 expression in PANC-1. Interestingly, the expression of CD44 and CD24 returned to initial levels once the medium was changed back from serum-free to serum-containing medium. No significant change in the expression of CD44 was detected in MIA-Paca-2. Furthermore, the relative quantification of SHH mRNA in PANC-1 cell spheres was significantly higher than that in cells cultured in the serum-containing medium. CONCLUSION: The expression patterns of the pancreatic cancer stem cell surface markers CD44, CD24 and ESA were diverse in different pancreatic adenocarcinoma cell lines and changed with their local microenvironment.


Assuntos
Adenocarcinoma/imunologia , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Antígeno CD24/metabolismo , Moléculas de Adesão Celular/metabolismo , Receptores de Hialuronatos/metabolismo , Células-Tronco Neoplásicas/imunologia , Neoplasias Pancreáticas/imunologia , Microambiente Tumoral , Adenocarcinoma/genética , Adenocarcinoma/patologia , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial , Citometria de Fluxo , Proteínas Hedgehog/genética , Humanos , Células-Tronco Neoplásicas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Esferoides Celulares
8.
Huan Jing Ke Xue ; 42(3): 1065-1072, 2021 Mar 08.
Artigo em Zh | MEDLINE | ID: mdl-33742902

RESUMO

With the rapid development of China's economy and society, the polycyclic aromatic hydrocarbon (PAH) pollution of surface soil has attracted increasing attention. Based on a systematic review, this study identified 166 relevant papers (published from 2000 to 2020) dealing with the contamination of 16 PAHs in the surface soil of China and summarized the pollution level, temporal, and spatial distribution influencing factors of PAHs with statistics, spatial interpolation analysis, and source analysis methods. The results showed that the surface soil of China has been polluted by human-caused PAHs, with a median concentration of 675.70 µg·kg-1. Although the overall condition is good, some sampling points have been seriously polluted. Among the monomers of PAHs, the concentrations of fluoranthene (Fla) and pyrene (Pyr) are high, while acenaphthylene (Acy) and acenaphthene (Ace) are relatively low. During the survey period, the concentration data of surface soil PAHs are generally within the moderate pollution levels of 313.10-1070.45 µg·kg-1, while the annual changes of PAHs do not show obvious fluctuations and are less affected by oil production and consumption. Statistics and spatial interpolation results show that PAH pollution in the surface soil of China has regional characteristics, where the concentration decreases in order from northwest, north, east, northeast, southwest, and south-central China. The pollution level in most provinces is "contaminated" or "weakly contaminated." From the source analysis results, PAH pollution in surface soils in most areas of China comes from the high-temperature combustion of fossil fuels such as petroleum, biomass, and coal. Heilongjiang and some northwestern regions (e.g., Xinjiang and Tibet) were mainly represented by oil source pollution. Such results could provide a reference for soil environmental management and PAH pollution control in China.

9.
Leuk Lymphoma ; 61(5): 1084-1096, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-29334312

RESUMO

More than half of the patients with acute myeloid leukemia (AML) fail to achieve long-term disease-free survival with current therapies and novel therapeutic strategies are urgently needed. The effects of homoharringtonine (HHT) on the growth of AML cell lines and primary leukemia cells were examined using MTT, colony formation assay. The effects of HHT on both eukaryotic translation initiation factor 4E (eIF4E) and phospho-eIF4E(p-eIF4E) were examined through western blot and immunofluorescence staining. HHT selectively reduced levels of p-eIF4E and its downstream oncoprotein Mcl-1, and potently inhibited in vitro and in vivo the growth of a distinct subset of AML cells and primary leukemia cells expressing high level of p-eIF4E through apoptosis. Our findings suggest that HHT might be a first-in-class p-eIF4E-targeted drug and offer a novel therapeutic option for AML patients expressing high level of p-eIF4E.


Assuntos
Leucemia Mieloide Aguda , Apoptose , Linhagem Celular Tumoral , Fator de Iniciação 4E em Eucariotos/genética , Mepesuccinato de Omacetaxina , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Fatores de Iniciação de Peptídeos
10.
Cancer Biomark ; 23(3): 363-371, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30223388

RESUMO

OBJECTIVE: The aim of this study was to investigate the correlation of katanin P80 expression with clinicopathological features and overall survival (OS) in surgical breast cancer (BC) patients. METHODS: Four hundred and fourteen BC patients underwent surgery were analyzed in this retrospective cohort study. Katanin P80 expression was examined by immunofluorescence assay. The median follow-up duration was 118.0 months (quantiles: 99.0-140.5 months), the last follow-up date was Jul 1st 2017. RESULTS: Eighty-five patients (20.5%) with katanin P80 positive expression and 329 patients (79.5%) with katanin P80 negative expression were observed in this research. Katanin P80 positive expression was correlated with higher N stage (p< 0.001) and TNM stage (p< 0.001). K-M curve and log-rank test revealed that katanin P80 positive patients presented with shorter OS compared with katanin P80 negative patients (p< 0.001). Multivariate Cox's regression analysis disclosed that katanin P80 positive expression (p< 0.001) and histologic grade (p< 0.001) could independently predict unfavorable OS. Furthermore, subgroups analysis was performed, which illuminated that katanin P80 positive expression was correlated with shorter OS in all subgroups divided by molecular subtyping and TNM stage (all p< 0.05) except in TNM stage I subgroup (p= 0.573). CONCLUSION: Katanin P80 expression positively correlated with lymph node metastasis and could abe a novel biomarker for prognosis in BC patients.


Assuntos
Adenosina Trifosfatases/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Prognóstico , Adulto , Idoso , Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/cirurgia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(4): 1079-1085, 2018 Aug.
Artigo em Zh | MEDLINE | ID: mdl-30111411

RESUMO

OBJECTIVE: To investigate the prognostic value of morphology and Hans classification in diffuse large B cell lymphoma(DLBCL). METHODS: Clinical data of 249 patients diagnosed with DLBCL in our hospital and Hangzhou Xixi hospital during Jan 2006 to Dec 2016 were analyzed retrospectively. These patients were classified into 3 groups: immunoblastic variant(IB) group, centroblastic variant(CB) group and others group according to the cell morphology. And DLBCL was also divided into GCB(germinal center B-cell-like)or non-GCB(non-germinal center B-cell-like) group by analyzing the expression of CD10, BCL6 and MUM1 (GCB: CD10 +,BCL6+-,MUM1+-/CD10-,BCL6+,MUM1-;non-GCB:CD10-,BCL6-,MUM1+-/CD10-,BCL6+,MUM1+). RESULTS: The univariate analysis displayed that the age,LDH level,IPI,IB,non-GCB,B-symptoms and rituximab all could influence the OS and EFS, the CR rate of CB subtype patients was significantly higher than that of the patients with IB subtype (68.3% vs 38.9%)(P=0.02). IB subtype was the in dependent prognostic factor for both EFS and OS in the whole study. In multivariate analysis, IPI and IB were the independent prognostic factors for OS and EFS. IB subtype was also an independent prognostic factor in EFS and OS with or without rituximab. The expression of BCL2 and BCL6 was related with prognosis in R-CHOP, but not in CHOP treated patients. Other markers (CD5, CD10, IRF4/MUM1, HLA-DR and Ki-67 proliferation index) were not of the significant prognostic value for DLBCL. When accepted rituximab, the GCB and non-GCB were not different significantly for prognosis. However, the non-GCB group showed a poor prognosis without using rituximab (EFS P=0.020;OS P=0.020). Multivariate Cox models showed that OS and EFS were not significantly different between GCB and non-GCB group, however, the IB subtype had a very significantly poor prognosis in OS and EFS (P=0.001, P=0.002). When the analysis was restricted to DLBCL with CB morphology only, no prognostic value was observed in Hans classification. CONCLUSION: The subtype of immunoblast is a major risk factor in patients treated with CHOP or R-CHOP. There is a significant association between the Hans classification and the morphologic subclassification. Results of this study have supplemented the data for the prognostic factor of DLBCL and demonstrated that the cytomorphologic diagnosis can be reproducible.


Assuntos
Linfoma Difuso de Grandes Células B , Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida , Doxorrubicina , Humanos , Imuno-Histoquímica , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Rituximab
12.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 33(1): 78-82, 2017 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-29926610

RESUMO

OBJECTIVE: To investigate the effects of long non-coding RNA SPRY4-IT1 (LncRNA) on proliferation and metastasis of medul-loblastoma cells. METHODS: SPRY4-IT1siRNA and control fluorescence siRNA were transfected into medulloblastoma cell line Daoy with Lipo-fe ctamine 2000 and were divided into control group and si-SPRY4-IT1 group. Relative expression of SPRY4-IT1 mRNA were detected by real-time quantitative PCR. The change of cell proliferation were examined using CCK-8 kit and clone forming experiment. The change of cell inva-sion and metastasis were examined by matrigel invasion assay and cell metastasis experiment respectively, The expression of matrix metallopro-teinase MMP-2 and MMP-9 were detected by Western blot. RESULTS: In si-SPRY4-IT1 group,the SPRY4-IT1 mRNA expression level, cell pro-liferation in vitro,cell invasion and migration ability, MMP-2 protein expression were significantly lower than those in the control group. CONCLUSIONS: Interference SPRY4-IT1 expression has prominent inhibitory effect on the cell proliferation、invasion and metastasis of medulloblastoma cell line Daoy.


Assuntos
Proliferação de Células , Neoplasias Cerebelares/patologia , Meduloblastoma/patologia , Metástase Neoplásica , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo
13.
Ying Yong Sheng Tai Xue Bao ; 28(4): 1281-1288, 2017 Apr 18.
Artigo em Zh | MEDLINE | ID: mdl-29741326

RESUMO

Scale and intensive development of mixed crop-livestock agriculture is inevitable in North China Plain (NCP), and nitrogen (N) is one of the key elements that linked the crop and livestock production. Here, we used Hebei Jinlong Circular Agriculture Farm as an example, to analyze the N flow and use efficiency, by using data from literature, on-farm survey and modeling. Further, several on-farm N management improvement practices were proposed and evaluated through scenario analysis, to supply technical support and scientific basis not only for achieving higher N use efficiency and productivity at the farm level, but also providing a new model of circular agriculture in NCP. Our results indicated that manure and purchased fertilizer were the main N input in crop production, which amounted to 674.6 kg N·hm-2·a-1 and accounted for 88.3% of the total N input. Of all the N input in crop production system, only 41.5% ended up in the crop products and around 190.7 kg N·hm-2·a-1 surplus. The excess input of synthetic fertilizer was the main reason for low N use efficiency and high N surplus for crop system. Purchased feed was the main N input pathway in livestock production system, and accounted for 83.2% of the total N input. The annual N excretion rate was 776.6 t N, and around 36.3% of the excreted N was recycled to the crop system. The N use efficiency was 19.7% for livestock production system. The N use efficiency was 40.7% at the whole farm level. The scenarios analysis showed that reducing purchased fertilizer N input by 50% (scenario 1) and increasing the total maize production via adjustment of cropping structure (scenario 2) would increase the N use efficiency in cropping system by 18.7% and 9.8%, respectively. The whole farm use efficiency could be increased by 19.1% through optimizing the feed compositions and regimes (scenario 3). Therefore, reducing purchased fertilizer N input, adjustment of cropping structure and optimizing the feed compositions could increase the N production capacity and achieve an environmental friendly mixed crop-livestock production system simultaneously in NCP.


Assuntos
Gado , Nitrogênio , Agricultura , Animais , China , Produtos Agrícolas , Medicamentos de Ervas Chinesas , Fazendas , Fertilizantes
14.
Artigo em Zh | MEDLINE | ID: mdl-27255048

RESUMO

OBJECTIVE: To investigate the apoptosis and proliferation effect of matrine on human medulloblastoma cell line D341 in vitro and the effect of the expression of the related caspase 3 and caspase 9 proteins. METHODS: The D341 cells were cultivated successfully in vitro. Then the cells were divided into 5 groups according to the concentration of matrine (0.5 mg/mI group, 1.0 mg/ml group, 1.5 mg/ml group, 2.0 mg/ml group and the control group was 0 mg/ml). All the experiments were repeated three times. The cell morphologic and structure change was observed with the optical microscope and the transmission electron microscope. The proliferation of D341 cell was analyzed using Cell Counting Kit-8 assay. Apoptosis was detected by Annexin V-FITC/PI double staining. The expression of Caspase3 and Caspase9 was detected by Western blot. RESULTS: With the effect of matrine, the proliferation inhibition rate gradually increased with drug concentrations increasing, and there was a significant difference (P < 0.01). The inhibitory effect of matrine on cell proliferation was different with the different treatment time, there was a significant difference between the 24 h to 72 h groups (P < 0.01). The apoptotic rate increased with matrine concentrations increasing. There were significant differences between the group of 0.5 mg/mI or 1.0 mg/mI to the group of 1.5 mg/mI or 2.0 mg/mI (P < 0.05). The apoptotic rate increased with the prolonged treatment time. There were significant differences between the group of 24 h or 48 h to the group of 72 h ( P < 0.05). With the increase of matrine concentration, the expression of Caspase 3 and Caspase 9 increased (P < 0.01). CONCLUSION: Matrine induces the apoptosis, and inhibits the proliferation of human medulloblastoma D341 cells in vitro by up-regulation of the expression level of Caspase3, Caspase9.


Assuntos
Apoptose , Caspase 3/metabolismo , Caspase 9/metabolismo , Proliferação de Células , Neoplasias Cerebelares/patologia , Meduloblastoma/patologia , Alcaloides/farmacologia , Linhagem Celular Tumoral , Neoplasias Cerebelares/metabolismo , Humanos , Meduloblastoma/metabolismo , Quinolizinas/farmacologia , Regulação para Cima , Matrinas
15.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 32(2): 132-136, 2016 Feb 08.
Artigo em Zh | MEDLINE | ID: mdl-29931864

RESUMO

OBJECTIVE: To investigate the effect of demethylation of Syk gene promoter by the methylation transferase inhibitor 5-aza-CdR on the invasion and metastasis of medulloblastoma cell line Daoy. METHODS: Medulloblastoma cell line Daoy was treated with 5-aza-CdR in vitro. Methylation-specific PCR, real time-PCR and Western blot were used to detect Syk gene promoter methylation status, Syk mRNA and protein expression respectively. Transwell was employed to study the invasion and metastasis of medulloblastoma cell line Daoyby counting the cells that had invaded through Matrigel and migrated to the undersurface of the membrane before and after treatment of 5-aza-CdR. RESULTS: In comparison to control group, Syk gene promoter of 5-aza-CdR-treated groups was demethylated and expression of Syk mRNA and protein was significantly up-regulated by 3.40±0.24 folds (P<0.01) and 3.23±0.19 folds (P<0.01) respectively. The invasiveness and metastasis of medulloblastoma cell line Daoy was decreased(P<0.05). CONCLUSIONS: Hypermethylation of Syk gene promoter is responsible for the down-regulation of Syk gene expression in medulloblastoma cell line Daoy, which may be one of the mechanisms that enhanced cell invasion and metastasis. While 5-aza-CdR can reverse the hypermethylation of Syk gene promoter and restore Syk gene expression and thus suppresses invasiveness and metastasis of tumor cells.


Assuntos
Azacitidina/farmacologia , Movimento Celular , Neoplasias Cerebelares/metabolismo , Metilação de DNA , Meduloblastoma/metabolismo , Regiões Promotoras Genéticas , Quinase Syk/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica
16.
J Zhejiang Univ Sci B ; 6(11): 1107-14, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16252346

RESUMO

Diagnostic ultrasound is a useful and noninvasive method in clinical medicine. Although due to its qualitative, subjective and experience-based nature, ultrasound image interpretation can be influenced by image conditions such as scanning frequency and machine settings. In this paper, a novel method is proposed to extract the liver features using the joint features of fractal dimension and the entropies of texture edge co-occurrence matrix based on ultrasound images, which is not sensitive to changes in emission frequency and gain. Then, Fisher linear classifier and support vector machine are employed to test a group of 99 in-vivo liver fibrosis images from 18 patients, as well as other 273 liver images from 18 normal human volunteers.


Assuntos
Algoritmos , Inteligência Artificial , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Cirrose Hepática/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Fractais , Humanos , Armazenamento e Recuperação da Informação/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(2): 307-10, 2005 Feb.
Artigo em Zh | MEDLINE | ID: mdl-15852885

RESUMO

A novel method for spectral similarity measure, which is called nonlinear spectral angle mapper, is presented. In this method, on one hand, nonlinear transformation and removing high relativity among bands are used through kernel PCA; on the other hand, the feature of both spectral reflection and absorption are combined in transformed space. At last, spectral angle mapper is used to measure spectral similarity. The authors' experiments show that this method is effective in spectral similarity retrieval.


Assuntos
Algoritmos , Óxidos/química , Análise Espectral/estatística & dados numéricos , Absorção , Modelos Estatísticos , Dinâmica não Linear , Reconhecimento Automatizado de Padrão , Análise Espectral/métodos
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(8): 1180-3, 2005 Aug.
Artigo em Zh | MEDLINE | ID: mdl-16329474

RESUMO

Based on the analysis of the error sources for spectral anglemapping (SAM), several key elements are pointed out, i.e. the change of wave band location, the change of the attribution ratio, the random change of attribution, and the whole translation of wave band. After the above-mentioned four error sources are analyzed, the authors present several improvement algorithms, viz. calculating the spectral angle with grouping, normalization and intersection. The grouping method can resolve the pseudo-similar problem, because it considers both spectral global features and local features. Calculating spectral angle with normalization restrains those random errors in original data by normalizing the spectral vectors. The intersection method can eliminate the error elicited by the whole wave translation. Therefore, it can be employed to correctly identify spectral class. Experiments show that those improvement algorithms are effective and can be used to process spectral data with errors.


Assuntos
Algoritmos , Análise Espectral/métodos , Interpretação de Imagem Assistida por Computador/métodos , Padrões de Referência , Reprodutibilidade dos Testes , Análise Espectral/normas
19.
Zhongguo Yi Liao Qi Xie Za Zhi ; 29(3): 170-2, 2005 May.
Artigo em Zh | MEDLINE | ID: mdl-16124620

RESUMO

The optometry in physical examinations is conducted manually at present and this method is neither precise nor efficient. After studying the standard logarithmic visual acuity charts which is popular in our country, we have designed an optometry system based on Client/Server Computing Mode. The system's architecture and its working principle are also presented in the article.


Assuntos
Algoritmos , Armazenamento e Recuperação da Informação/métodos , Optometria/instrumentação , Inteligência Artificial , Simulação por Computador , Desenho de Equipamento , Humanos , Microcomputadores , Optometria/métodos , Exame Físico/instrumentação , Exame Físico/métodos , Design de Software
20.
Chem Commun (Camb) ; 51(19): 3985-8, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25620743

RESUMO

Two cationic heterometal-organic frameworks (Eu-Zn (1·NO3⁻) and Tb-Zn (2·NO3⁻)) with NO3(-) counter-anions in the channels are structurally and luminously characterized. Both of them can serve as highly sensitive and highly selective luminescent probes for detecting I(-) ions in aqueous solutions. In particular, 2·NO3⁻ can selectively and reversibly detect I(-) with a fast response time of just 10 s and an extremely low detection limit of 0.001 ppm. Mechanism studies reveal that I(-) is quickly oxidized to form I3⁻with the help of 1·NO3⁻ or 2·NO3⁻, leading to luminescence quenching. This represents the first report of MOF-based luminescent probes for the detection of I(-) in aqueous solutions.


Assuntos
Iodo/análise , Iodo/química , Substâncias Luminescentes/química , Compostos Organometálicos/química , Térbio/química , Água/química , Medições Luminescentes , Modelos Moleculares , Conformação Molecular , Soluções
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