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1.
Mar Biotechnol (NY) ; 23(2): 201-214, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33580373

RESUMO

Sexual dimorphism is common across the animal kingdom. Knowledge of the mechanisms of sexual size dimorphism is limited although it is important in biology and aquaculture. Tilapia is the common name for ~ 100 species of cichlid fish. Some are important aquaculture species and males outgrow females. To gain novel insights into the mechanisms underlying sexual size dimorphism, we analyzed the differences of brain transcriptomes between males and females in Mozambique tilapia and studied the function of the pro-opiomelanocortin (Pomc) gene in tilapia and zebrafish. The transcriptome analysis identified 123, 55, and 2706 sex-biased genes at 5, 30, and 90 dph (days post-hatch), respectively, indicating sexual dimorphism of gene expressions in the brain. The expression of Pomc in the tilapia brain was a female-biased at 30, 90, and 120 dph. An analysis of the DNA sequence located upstream of the tilapia Pomc transcriptional start site identified two estrogenic response elements. In vitro luciferase assay of the two elements revealed that ß-estradiol significantly enhanced the expression of luciferase activity, suggesting that the expression of Pomc is mediated by estrogen. We knocked out Pomc in zebrafish using Crispr/Cas-9. The Pomc-knockout zebrafish showed faster growth and higher sensitivity to feeding as compared to the wild-type fish. Taken together, our results indicate that Pomc contributes to sexual size dimorphism and suggest that the high estrogen level in females promotes the expression of Pomc and suppresses feeding in female tilapias, which leads to the slower growth of female tilapias.


Assuntos
Pró-Opiomelanocortina/genética , Caracteres Sexuais , Tilápia/genética , Peixe-Zebra/genética , Animais , Encéfalo/metabolismo , Estrogênios , Comportamento Alimentar/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Inativação de Genes , Masculino , Análise de Sequência de DNA , Tilápia/crescimento & desenvolvimento , Peixe-Zebra/crescimento & desenvolvimento
2.
J Hazard Mater ; 267: 229-37, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24462892

RESUMO

Using a sol-gel method, SmMeOx/MCM-41 or SBA-15 (Me=Fe, Co and Zn) and corresponding unsupported sorbents were prepared. The desulfurization performance of these sorbents was evaluated over a fixed-bed reactor and the effects of reaction temperature, feed and sorbent composition on desulfurization performance were studied. Samarium-based sorbents used to remove H2S from hot coal gas were reported for the first time. The results of successive sulfidation/regeneration cycles revealed that SmFeO3/SBA-15 sorbent was suitable for desulfurization of hot coal gas in the chemical industry. The formation of elemental sulfur during both sulfidation and regeneration processes depended strongly on the catalytic action of Sm2O2S species, which was confirmed for the first time via high sensitive time of flight mass spectrometer (TOF-MS) using 6%vol(18)O2/Ar regeneration gas and can reduce markedly procedural complexity. The sorbents were characterized using N2-adsorption, high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), temperature-programmed reduction of H2 (H2-TPR), thermogravimetry (TG) and time-of-flight mass spectrometry (TOF-MS) techniques.


Assuntos
Carvão Mineral/análise , Poluição Ambiental/prevenção & controle , Oxigênio/química , Samário/química , Enxofre/química , Adsorção , Algoritmos , Varredura Diferencial de Calorimetria , Gases , Temperatura Alta , Sulfeto de Hidrogênio/química , Microscopia Eletrônica de Transmissão , Isótopos de Oxigênio , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Difração de Raios X
3.
J Hazard Mater ; 233-234: 219-27, 2012 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-22835768

RESUMO

A series of mesoporous xCuyMn/SBA-15 sorbents with different Cu/Mn atomic ratios were prepared by wet impregnation method and their desulfurization performance in hot coal gas was investigated in a fixed-bed quartz reactor in the range of 700-850°C. The successive nine desulfurization-regeneration cycles at 800°C revealed that 1Cu9Mn/SBA-15 presented high performance with durable regeneration ability due to the high dispersion of Mn(2)O(3) particles incorporated with a certain amount of copper oxides. The breakthrough sulfur capacity of 1Cu9Mn/SBA-15 observed 800°C is 13.8 g S/100g sorbents, which is remarkably higher than these of 40 wt%LaFeO(3)/SBA-15 (4.8 g S/100g sorbents) and 50 wt%LaFe(2)O(x)/MCM-41 (5.58 g S/100g sorbents) used only at 500-550°C. This suggested that the loading of Mn(2)O(3) active species with high thermal stability to SBA-15 support significantly increased sulfur capacity at relatively higher sulfidation temperature. The fresh and used xCuyMn/SBA-15 sorbents were characterized by means of BET, XRD, XPS, XAES, TG/DSC and HRTEM techniques, confirmed that the structure of the sorbents remained intact before and after hot coal gas desulfurization.


Assuntos
Poluentes Atmosféricos/química , Carvão Mineral , Cobre/química , Manganês/química , Dióxido de Silício/química , Enxofre/química , Adsorção , Poluição do Ar/prevenção & controle , Temperatura Alta
4.
J Biomed Mater Res A ; 78(2): 283-90, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16637045

RESUMO

Medical Polyacrylamide Hydrogel (PAMG)has been used in plastic and aesthetic surgery for years. However, its safety is still in doubt in many countries. In the current research, first an approach, using high performance liquid chromatography (HPLC), to determine the amount of residual acrylamide monomer (AM) in the PAMG was presented. Then the cytotoxicity of PAMG was investigated using cell counting and methyl thiazolyl tetrazolium (MTT) assay. To explore the mechanism of this toxicity, normal human fibroblasts cultured in medium extracts were analyzed. Membrane changes and other related parameters were investigated using flow cytometry (FCM). Real time fluorescent polymerase chain reaction (real time PCR) was also introduced to determine the biological response of the fibroblasts. During this process, three representative genes (p53, beta-actin, and c-myc, which are tumor suppressor genes, housekeeping genes, and proto-oncogenes respectively) were selected for examination. Results indicated that a method based on HPLC is practical and simple for determining AM in PAMG. The detection limits can reach the desired ppb level, and so it can fully meet the requirements of the studies of PAMG. Polyacylamide Hydrogel inhibits the growth of human fibroblasts and may cause the apoptosis of human fibroblasts. Moreover, it can alter physical parameters such as the size and the granularity of these cells. Furthermore, these three genes have a relatively typical amplification plot and highly related, wide-range standard curves, and so this reaction system is definitely suitable for the semiquantification of these genes. PAMG induces the increase of the message ribonucleic acid (mRNA) expression of c-myc, while the p53 and beta-actin remain even. This change is not related to the concentration of AM in the gel and may be incited by other components in the extract of PMAG.


Assuntos
Resinas Acrílicas/análise , Fibroblastos/citologia , Regulação da Expressão Gênica , Genes myc , Anexina A5/metabolismo , Sobrevivência Celular , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Fibroblastos/fisiologia , Citometria de Fluxo , Géis , Humanos , Reação em Cadeia da Polimerase/métodos , RNA/genética , RNA/isolamento & purificação
5.
Lin Chuang Er Bi Yan Hou Ke Za Zhi ; 14(3): 114-5, 2000 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12541411

RESUMO

OBJECTIVE: To investigate a new method with interventional embolization and pingyugmycin injection for treating nasofacial Hemangioma. METHOD: The fillets and coil were used for interventional embolization facial artery, internal maxillary artery, temporal superficial artery, and pingyungmycin injected for 4 patients. RESULT: The tumor and vascular beat in this series of 4 patients were disappeared by follow up of one year. There are not nasal obstruction and epistaxis. CONCLUSION: Treatment with interventional embolization and pingyungmycin injection is a safe and effective method for nasofacial hemangioma.


Assuntos
Embolização Terapêutica , Neoplasias Faciais/terapia , Hemangioma/terapia , Neoplasias Nasais/terapia , Adolescente , Adulto , Antibióticos Antineoplásicos/administração & dosagem , Bleomicina/administração & dosagem , Bleomicina/análogos & derivados , Criança , Terapia Combinada , Feminino , Humanos , Injeções Intralesionais , Masculino
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