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1.
Eur Rev Med Pharmacol Sci ; 25(7): 2824, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33877675

RESUMO

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "MicroRNA-1269a promotes the occurrence and progression of osteosarcoma by inhibiting TGF-ß1 expression, by S.-N. Yu, Y.-Y. Miao, B.T. Zhang, Y.-M. Dai, L. Liu, Z.-L. Gao, G.-F. Liu, published in Eur Rev Med Pharmacol Sci 2019; 23 (3): 972-981-DOI: 10.26355/eurrev_201902_16984-PMID: 30779063" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/16984.

2.
Eur Rev Med Pharmacol Sci ; 23(3): 972-981, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30779063

RESUMO

OBJECTIVE: MicroRNAs are endogenous, non-coding small RNAs that are capable of regulating biological and pathological processes. Previous studies have shown that microRNA-1269a serves as an oncogene. However, the role of microRNA-1269a in the pathogenesis of osteosarcoma (OS) has not been reported. The aim of this work was to investigate the expression characteristics of microRNA-1269a in OS and to further study its regulatory effects on the malignant progression of OS. PATIENTS AND METHODS: The expression of microRNA-1269a in 61 pairs of OS tissues and para-cancerous tissues was detected by quantitative Real Time-polymerase Chain Reaction (qRT-PCR). Chi-square test was used to analyze the relationship between microRNA-1269a expression and the characteristics of OS patients, including age, sex, clinical stage and distant metastasis. Subsequently, microRNA-1269a expression in OS cell lines was detected as well. After knockdown of microRNA-1269a by constructing relevant small interference RNA, biological performances of MG63 and U2OS cells were accessed by cell counting kit-8 (CCK-8), colony formation and transwell assay. Meanwhile, the protein expressions of key genes in the EMT/Smad pathway were detected by Western blot. Finally, si-TGF-ß1 (transforming growth factor-ß1) was transfected into OS cells, and cell migration and invasion were detected by transwell assay. RESULTS: MicroRNA-1269a was highly expressed in OS tissues compared with para-cancerous tissues. High expression of microRNA-1269a was positively correlated with young OS patients and high rate of distant metastasis, whereas was not correlated with age, sex and Enneking stage. Kaplan-Meier survival curves showed that high expression of microRNA-1269a was significantly associated with poor prognosis of OS. The knockdown of microRNA-1269a in MG63 and U2OS cells significantly inhibited cell proliferation, migration and invasion. Meanwhile, microRNA-1269a knockdown in OS cells markedly downregulated the expressions of TGF-ß1, p-Smad2, p-Smad3, N-cad, Vimentin and MMP9. Furthermore, TGF-ß1 knockdown remarkably decreased migratory and invasive abilities of OS cells. CONCLUSIONS: MicroRNA-1269a is highly expressed in OS, which is remarkably correlated with tumor stage, distant metastasis and poor prognosis of OS. In addition, microRNA-1269a promotes the malignant progression of OS by regulating TGF-ß1 expression.


Assuntos
MicroRNAs/fisiologia , Osteossarcoma/fisiopatologia , Fator de Crescimento Transformador beta1/biossíntese , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , MicroRNAs/biossíntese , Invasividade Neoplásica/fisiopatologia , Osteossarcoma/diagnóstico , Osteossarcoma/metabolismo , Prognóstico , RNA Interferente Pequeno/farmacologia , Transfecção , Fator de Crescimento Transformador beta1/genética , Ensaio Tumoral de Célula-Tronco
4.
Zhonghua Yi Xue Za Zhi ; 96(43): 3499-3503, 2016 Nov 22.
Artigo em Chinês | MEDLINE | ID: mdl-27903346

RESUMO

Objective: To evaluate the effect of snow sports to the knee cartilage maturation of children and adolescent with quantitative analysis of 3.0 T MRI. Methods: Twenty children and adolescent who underwent snow sports training more than 6 months (11 males and 9 females) were recruited and named with sports group, and twenty children and adolescent who live regularly without any exercise (10 males and 10 females) were recruited as control group from June 2014 to June 2015.Each group was divided into subgroups according to their gender.Both groups were scanned by 3.0 T MR.According to the loading features of knee articular cartilage in snow sports, medial femoral condyle, lateral femoral condyle, medial tibial condyle and lateral tibial condyle were divided into subareas.T2 values and cartilage thickness were measured in all areas. Results: The median ages of the sports group and control group were 14.2 and 13.6 years old, which showed no statistical difference between two groups.The BMI of the sports group and control group were 18.3 and 17.9 kg/m2, which showed no statistical difference between two groups.Both in sports group and control group, the thickness and T2 values of all areas showed significant differences between man and women in each group (all P<0.05). The cartilage thickness of sports group was higher than control group (P<0.05). The T2 values showed no statistical difference in anterior central, posterior central of femoral condyles and anterior, central areas of tibial condyles between sports group and control group(P≥0.05). The T2 values of anterior part of posterior femur and posterior areas of tibial condyle in sports group was higher than control group (P≥0.05). Conclusion: Gender difference may be an important effect factor of cartilage thickness. Scientific snow sports training maybe has positive influence for cartilage maturation of children and adolescent.


Assuntos
Cartilagem Articular , Articulação do Joelho , Esportes na Neve , Adolescente , Epífises , Fêmur , Humanos , Imageamento por Ressonância Magnética , Tíbia
5.
Opt Express ; 20(20): 22448-53, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-23037393

RESUMO

We have demonstrated a laser-diode pumped continuous-wave (CW) and passively Q-switched laser with a Nd:Sc(0.2)Y(0.8)SiO(5) (Nd:SYSO) crystal for the first time. In the CW operation, the laser was found to oscillate in tri-wavelength regime at 1074.8 nm, 1076.6 nm and 1078.2 nm, respectively. The maximum CW output power of 1.96 W was obtained, giving an optical-to-optical conversion efficiency of 35% and a slope efficiency of 39%. Using either Cr(4+):YAG or V(3+):YAG crystal as saturable absorber, stable passively Q-switched laser was obtained at dual-wavelength of 1074.8 nm and 1078.2 nm with orthogonal-polarization. The maximum average output power, pulse repetition rate, and shortest pulse width were 1.03 W, 50 kHz, and 24 ns, respectively. The passively Q-switched dual-wavelength laser could be potentially used as a source for generation of terahertz radiation.


Assuntos
Lasers de Estado Sólido , Refratometria/instrumentação , Desenho Assistido por Computador , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento
6.
Radiat Environ Biophys ; 50(3): 383-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21656249

RESUMO

Our work aims to understand the effects of shielding on the induction of biological damage by heavy charged particles and to compare the shielding effects of different materials at the same LET from two aspects: the biological effectiveness including or not including secondary particles emitted at large angles and the biological effectiveness at different angles with respect to the beam direction. We designed and conducted biological experiments to determine the biological effectiveness of 200 MeV/u carbon ions after traversing different shielding materials (Lucite and aluminium). Whole blood samples, which were either attached to the shielding material (48 mm Lucite or 29 mm aluminium)or positioned at 300 cm away from it at different angles with respect to the beam axis, were exposed to carbon ion beams. For comparison, whole blood samples were exposed directly to 200 MeV/u carbon ions. Chromosomal aberrations in lymphocytes were scored. The results indicated that the biological effectiveness per unit dose was not significantly changed by 48 mm Lucite or 29 mm aluminium, and no significant differences were observed in lymphocytes attached to the target and in lymphocytes positioned at a distance of 300 cm away from the target, at 0º angle of the beam axis. However, when plotted as a function of the number of ions hitting the shielding target, the curves are separated and the shield increases the effectiveness per unit ion. The frequency of chromosomal aberrations at tilted angles behind 29 mm Al and 48 mm Lucite was almost the same. These lesions were considered to be caused by secondary particles due to the passage of particles through the shielding materials.


Assuntos
Aceleração , Carbono/efeitos adversos , Análise Citogenética , Proteção Radiológica , Carbono/química , Aberrações Cromossômicas/efeitos da radiação , Humanos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Processos Estocásticos
7.
Appl Opt ; 48(32): 6371-5, 2009 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-19904338

RESUMO

A comparative study of a frequency-doubling 532 nm laser based on gray-tracking-resistant KTP (GTR-KTP) and conventional KTP is presented. The intracavity GTR-KTP was proved to have better temperature characteristics than that of conventional KTP. Within the normalized output power variation range of 0.8-1.0, GTR-KTP has a temperature tolerance of 35 degrees C, broader than the 21 degrees C obtained with conventional KTP. Under the laser diode (LD) pump power of 180 W, the maximum average output power at 532 nm was 40.6 W for GTR-KTP at a repetition frequency of 10 kHz. In the case of conventional KTP, the maximum available LD pump power was limited to 150 W, with the corresponding maximum green average output power of 27.2 W.

8.
Oncogene ; 18(28): 4099-107, 1999 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10435591

RESUMO

The retroviral Gag-like protein p58gag expressed in a highly metastatic ascites rat mammary adenocarcinoma has been implicated in cell surface changes contributing to xenotransplantability. p58gag is present in the cells in a plasma membrane- and microfilament-associated signal transduction particle containing Src and is phosphorylated on tyrosine. Overlay analyses and affinity chromatography with glutathione S-transferase (GST) fusion proteins of Src homology-3 (SH3) domains showed direct binding of the Src but not the Crk SH3 domain to p58gag. This association was confirmed by co-immunoprecipitation of partially purified p58gag from ascites cell lysates with platelet Src. Further, a GST-p58gag fusion protein bound full length c-Src from either platelets or c-Src-expressing insect cells. The GST-p58gag fusion protein, but not GST, was phosphorylated by platelet or insect cell-expressed c-Src, but not by a kinase negative c-Src variant. The binding of GST-p58gag to c-Src was almost completely abolished by a 50-fold excess of the GST-SH3 domain of Src, and a parallel decrease in tyrosine phosphorylation of p58gag was observed. These results demonstrate that p58gag is tyrosine-phosphorylated as a consequence of its specific association with c-Src via its SH3 domain. These observations suggest a mechanism by which Gag proteins may contribute to retroviral maturation or pathogenesis through binding and relocalization of SH3 domain-containing proteins such as Src-like tyrosine kinases to sites of association of microfilaments with the plasma membrane.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Animais , Ascite/metabolismo , Ligação Competitiva , Plaquetas/enzimologia , Feminino , Modelos Biológicos , Transplante de Neoplasias , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-crk , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Spodoptera/citologia , Transplante Heterólogo , Células Tumorais Cultivadas , Domínios de Homologia de src
9.
AIDS Res Hum Retroviruses ; 15(9): 811-20, 1999 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-10381169

RESUMO

HIV-1-associated brain pathology exhibits regional variability and we therefore studied the genetic differences in the V1-V5 domains of the HIV env gene in up to four regions of brain (frontal lobe, basal ganglia, medial temporal lobe, and nonmedial temporal lobe) from three patients. We found that in each separate brain region HIV-1 forms different quasispecies and that there is little gene flow among these regions. In further support of brain region-specific evolution of HIV-1, we analyzed amino acid signatures in these clones. In addition to known amino acid signatures associated with macrophage tropism and the lack of syncytium formation, we found 15 majority amino acid signature patterns from the V1-V5 env sequences associated with the neuroanatomical regions analyzed from the three individuals. Furthermore, on average, intrabrain genetic distances for the HIV-1 env were estimated to be much smaller than genetic distances between brain regions. Specific strains of HIV-1 may be neurotropic or neuroinvasive (replication preference in brain tissue) and may contribute to pathology, cognitive loss, and neuropsychiatric disease.


Assuntos
Encéfalo/virologia , Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/virologia , HIV-1/genética , Fragmentos de Peptídeos/genética , Adulto , Encéfalo/patologia , Evolução Molecular , Feminino , Genes Virais , Infecções por HIV/patologia , HIV-1/classificação , Humanos , Masculino , Filogenia , Análise de Sequência de DNA
11.
J Neuroimmunol ; 83(1-2): 88-101, 1998 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9610677

RESUMO

The epidemiology of cocaine abuse and potential relationships of cocaine withdrawal to human immunodeficiency virus type 1 (HIV-1)-associated dementia (HAD) are discussed. Neuroendocrinological changes in HIV-1 infection of the central nervous system (CNS) are discussed with the relevant impact of cocaine abuse. HIV-1 load in the brain tissue of infected substance users is described along with possible associations with neuropathology and HAD. Finally, the molecular epidemiology and sequence heterogeneity of HIV-1 and their implications for neuropathogenesis are summarized. The complex context of addressing cocaine abuse in the setting of HIV-1 infection appears more tractable when decomposed into its components.


Assuntos
Complexo AIDS Demência/epidemiologia , Cocaína/efeitos adversos , HIV-1 , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Vasoconstritores/efeitos adversos , Complexo AIDS Demência/etiologia , Complexo AIDS Demência/fisiopatologia , Humanos , Neuroimunomodulação/efeitos dos fármacos , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Transtornos Relacionados ao Uso de Opioides/virologia
13.
J Neurosci Res ; 41(5): 648-54, 1995 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7563245

RESUMO

The proliferation of neonatal Schwann cells (SCs) in response to mitogenic agents has been well analyzed in vitro, but a limited range of mitogens have been defined. We investigated whether three identified neonatal SC mitogens [glial growth factor (GGF), platelet-derived growth factor BB (PDGF-BB), and basic fibroblast growth factor (bFGF)] are required to stimulate mitosis of adult SCs. Adult SCs were isolated from mouse sciatic nerves by mechanical and chemical dissociation, following three experimental steps: 1) culturing the dissociated cells for 24 hr in 10% FCS-F12 medium, 2) culturing these cells in serum-free medium for the next 48 hr, and 3) purifying adult SCs by differential adhesion. We describe a new method for preparation of SCs from peripheral nerves of adult mouse that provides 99.5% pure SCs populations at cell yields of greater than 3 x 10(3) cells/mg of starting nerve wet weight within 5 culture days. Although mitosis of SCs in culture in response to mitogens requires the presence of serum, the complex nature of serum renders difficult a complete analysis of mitogens required for SCs DNA synthesis, so we examined the proliferating response of adult SCs to GGF, PDGF-BB, and bFGF in serum-free medium. GGF alone had mitogenicity for adult SCs in a dose-dependent manner, and synergistic activation coupling with forskolin was not observed. Neither PDGF-BB nor bFGF was mitogenic for adult SCs when used alone or with forskolin.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Mitógenos/farmacologia , Células de Schwann/citologia , Células de Schwann/efeitos dos fármacos , Envelhecimento/fisiologia , Animais , Divisão Celular/efeitos dos fármacos , Separação Celular , Células Cultivadas , Meios de Cultura Livres de Soro , AMP Cíclico/metabolismo , Imuno-Histoquímica , Membranas Intracelulares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células de Schwann/metabolismo
14.
Int J Neural Syst ; 5(1): 67-75, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7921386

RESUMO

Much previous work on training multilayer neural networks has attempted to speed up the backpropagation algorithm using more sophisticated weight modification rules, whereby all the given training examples are used in a random or predetermined sequence. In this paper we investigate an alternative approach in which the learning proceeds on an increasing number of selected training examples, starting with a small training set. We derive a measure of criticality of examples and present an incremental learning algorithm that uses this measure to select a critical subset of given examples for solving the particular task. Our experimental results suggest that the method can significantly improve training speed and generalization performance in many real applications of neural networks. This method can be used in conjunction with other variations of gradient descent algorithms.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Algoritmos , Fatores de Tempo
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