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1.
J Phys Condens Matter ; 33(15)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33498026

RESUMO

We report growth, electronic structure and superconductivity of ultrathin epitaxial CoSi2films on Si (111). At low coverages, preferred islands with 2, 5 and 6 monolayers height develop, which agrees well with the surface energy calculation. We observe clear quantum well states as a result of electronic confinement and their dispersion agrees well with density functional theory calculations, indicating weak correlation effect despite strong contributions from Co 3delectrons.Ex situtransport measurements show that superconductivity persists down to at least 10 monolayers, with reducedTcbut largely enhanced upper critical field. Our study opens up the opportunity to study the interplay between quantum confinement, interfacial symmetry breaking and superconductivity in an epitaxial silicide film, which is technologically relevant in microelectronics.

2.
Thromb Res ; 182: 56-63, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31450009

RESUMO

INTRODUCTION: Endotoxemia often results in systemic inflammatory response syndrome (SIRS), coagulation disturbance and acute lung injury (ALI), and such a condition is associated with the activation of platelets, leukocytes and vascular endothelial cells (VECs). P-selectin glycoprotein ligand 1 (PSGL-1) is a key regulatory molecule in the activation of platelets, leukocytes and VECs. However, it still remains largely unexplored whether PSGL-1 plays an important role in SIRS, coagulation dysfunction and ALI of endotoxemia. In the present study, we aimed to study the role of PSGL-1 in above-mentioned situations using endotoxemic mice. MATERIALS AND METHODS: An endotoxemia model was established in BALB/c mice via lipopolysaccharide (LPS) administration. Moreover, the mice were simultaneously injected with PSGL-1 antibody for intervention. The survival rate, morphologic changes of lung tissues, platelet-leukocyte adhesion, tissue factor expression on leukocytes, fibrinogen deposition in lung tissues, serum levels of inflammatory factors and the activation of VECs were determined. RESULTS: The results showed that the aggregation and recruitment of platelets and leukocytes in lung tissues, the expression of tissue factor on leukocytes, the serum levels of inflammatory factors, the activation of VECs, and the fibrinogen deposition in lung tissues were increased in endotoxemic mice, which were significantly alleviated by administration of PSGL-1 antibody. Moreover, blockade of PSGL-1 markedly increased survival rate, and alleviated coagulation disturbance and lung injury in endotoxemic mice. CONCLUSIONS: Taken together, PSGL-1 played an important role in pathogenesis of SIRS and coagulation dysfunction and ALI in endotoxemic mice.


Assuntos
Transtornos da Coagulação Sanguínea/imunologia , Endotoxemia/imunologia , Glicoproteínas de Membrana/imunologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Lesão Pulmonar Aguda/sangue , Lesão Pulmonar Aguda/complicações , Lesão Pulmonar Aguda/imunologia , Animais , Coagulação Sanguínea , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/complicações , Endotélio Vascular/imunologia , Endotoxemia/sangue , Endotoxemia/complicações , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Agregação Plaquetária , Síndrome de Resposta Inflamatória Sistêmica/sangue , Síndrome de Resposta Inflamatória Sistêmica/complicações
3.
BMC Plant Biol ; 18(1): 112, 2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29879910

RESUMO

BACKGROUND: Rice is highly sensitive to temperature fluctuations. Recently, the frequent occurrence of high temperature stress has heavily influenced rice production. Proper heading date in specific environmental conditions could ensure high grain yield. Rice heading greatly depends on the accurate measurement of environmental changes, particularly in day length and temperature. In contrary to the detailed understanding of the photoperiod pathway, little has been known about how temperature regulates the genetic control of rice heading. RESULTS: Near isogenic lines that were segregated for qHd1, were developed from a cross between indica rice varieties Zhenshan 97 (ZS97) and Milyang 46 (MY46). Using a five sowing-date experiment in the paddy field, we observed the involvement of qHd1 in temperature responses. With the gradual increase of temperature from Trial I to V, heading date of MY46 homozygotes continued to decrease for about 5 d per trial from 76 to 58 d, while that of ZS97 homozygotes was promoted at the same rate from Trial I to III and then stabilized at 69 d. This thermal response was confirmed in a temperature-gradient experiment conducted in the phytotron. It is also found that tolerance of the ZS97 allele to heading acceleration at high temperature was associated with higher grain weight that resulted in higher grain yield. Then, by qRT-PCR and RNA-seq, we found the pathway OsMADS51-Ehd1-RFT1/Hd3a underlying the qHd1-mediated floral response to temperature. By sequence comparison, OsMADS51 for qHd1 displayed a 9.5-kb insertion in the 1st intron of the ZS97 allele compared to the MY46 allele. Furthermore, this large insertion is commonly found in major early-season indica rice varieties, but not in the middle- and late-season ones, which corresponds to the requirement for high-temperature tolerance during the heading and grain-filling stages of early-season rice. CONCLUSIONS: Beneficial alleles at qHd1 confer tolerance to high temperatures at the heading and grain-filling stages, playing a significant role in the eco-geographical adaptation of early-season indica rice during modern breeding. These results, together with the underlying OsMADS51-Ehd1-RFT1/Hd3a floral pathway, provide valuable information for better understanding the molecular mechanism of temperature responsive regulation of heading date and yield traits in rice.


Assuntos
Grão Comestível/crescimento & desenvolvimento , Pleiotropia Genética/genética , Oryza/genética , Genes de Plantas/genética , Genes de Plantas/fisiologia , Pleiotropia Genética/fisiologia , Variação Genética/genética , Variação Genética/fisiologia , Resposta ao Choque Térmico , Temperatura Alta , Oryza/crescimento & desenvolvimento , Fotoperíodo , Melhoramento Vegetal , Locos de Características Quantitativas/genética , Locos de Características Quantitativas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
4.
PLoS One ; 9(6): e100423, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24945699

RESUMO

BACKGROUND: Our long-term field survey revealed that the Cardinium infection rate in Bemisia tabaci Q (also known as biotype Q) population was low in Shandong, China over the past few years. We hypothesize that (1) the Cardinium-infected (C+) B. tabaci Q population cannot efficiently compete with the Cardinium-uninfected (C-) B. tabaci Q population; (2) no reproductive isolation may have occurred between C+ and C-; and (3) the C- population has higher fitness than the C+ population. METHODOLOGY AND RESULTS: To reveal the differences in competitive ability and fitness between the two introduced populations (C+ and C-), competition between C+ and C- was examined over several generations. Subsequently, the reproductive isolation between C+ and C- was studied by crossing C+ with C- individuals, and the fitnesses of C+ and C- populations were compared using a two-sex life table method. Our results demonstrate that the competitive ability of the C+ whiteflies was weaker than that of C-. There is that no reproductive isolation occurred between the two populations and the C- population had higher fitness than the C+ population. CONCLUSION: The competitive ability and fitness differences of two populations may explain why C- whitefly populations have been dominant during the past few years in Shandong, China. However, the potential role Cardinium plays in whitefly should be further explored.


Assuntos
Comportamento Competitivo , Aptidão Genética , Hemípteros/fisiologia , Espécies Introduzidas , Animais , Bacteroidetes/fisiologia , China , Cruzamentos Genéticos , Feminino , Genes de Insetos , Hemípteros/genética , Hemípteros/crescimento & desenvolvimento , Hemípteros/microbiologia , Estágios do Ciclo de Vida , Masculino , Reprodução , Razão de Masculinidade , Análise de Sobrevida
5.
Lab Chip ; 14(7): 1230-45, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24525555

RESUMO

Cellular analysis plays important roles in various biological applications, such as cell biology, drug development, and disease diagnosis. Conventional cellular analysis usually measures the average response from a whole cell group. However, bulk measurements may cause misleading interpretations due to cell heterogeneity. Another problem is that current cellular analysis may not be able to differentiate various subsets of cell populations, each exhibiting a different behavior than the others. Single-cell analysis techniques are developed to analyze cellular properties, conditions, or functional responses in a large cell population at the individual cell level. Integrating optics with microfluidic platforms provides a well-controlled microenvironment to precisely control single cell conditions and perform non-invasive high-throughput analysis. This paper reviews recent developments in optofluidic technologies for various optics-based single-cell analyses, which involve single cell manipulation, treatment, and property detection. Finally, we provide our views on the future development of integrated optics with microfluidics for single-cell analysis and discuss potential challenges and opportunities of this emerging research field in biological applications.


Assuntos
Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/métodos , Técnicas Analíticas Microfluídicas/tendências , Retratos como Assunto
6.
Rice (N Y) ; 7(1): 13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26055995

RESUMO

The exploitation of male sterility systems has enabled the commercialization of heterosis in rice, with greatly increased yield and total production of this major staple food crop. Hybrid rice, which was adopted in the 1970s, now covers nearly 13.6 million hectares each year in China alone. Various types of cytoplasmic male sterility (CMS) and environment-conditioned genic male sterility (EGMS) systems have been applied in hybrid rice production. In this paper, recent advances in genetics, biochemistry, and molecular biology are reviewed with an emphasis on major male sterility systems in rice: five CMS systems, i.e., BT-, HL-, WA-, LD- and CW- CMS, and two EGMS systems, i.e., photoperiod- and temperature-sensitive genic male sterility (P/TGMS). The interaction of chimeric mitochondrial genes with nuclear genes causes CMS, which may be restored by restorer of fertility (Rf) genes. The PGMS, on the other hand, is conditioned by a non-coding RNA gene. A survey of the various CMS and EGMS lines used in hybrid rice production over the past three decades shows that the two-line system utilizing EGMS lines is playing a steadily larger role and TGMS lines predominate the current two-line system for hybrid rice production. The findings and experience gained during development and application of, and research on male sterility in rice not only advanced our understanding but also shed light on applications to other crops.

7.
Am J Bot ; 99(12): e493-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23196401

RESUMO

PREMISE OF THE STUDY: A new set of microsatellite or simple sequence repeat (SSR) markers from expressed sequence tags (ESTs) was developed for arum lily (Zantedeschia aethiopica), which is one of the most iconic and widely recognized ornamental plants in the world. • METHODS AND RESULTS: Using 2175 unigenes derived from 4283 random ESTs in arum lily, 166 primer pairs were designed and tested for amplification in 24 accessions from Asia, Europe, and Africa. A total of 43 loci were polymorphic, with the number of alleles per locus ranging from two to 10. The observed heterozygosity, expected heterozygosity, and polymorphism information content ranged from 0.2313 to 0.8480, 0.3034 to 0.8648, and 0.1015 to 0.7364, respectively. • CONCLUSIONS: These novel polymorphic EST-SSR markers will facilitate future studies of genetic variation and molecular-assisted breeding systems in arum lily.


Assuntos
Primers do DNA/genética , DNA de Plantas/genética , Etiquetas de Sequências Expressas , Repetições de Microssatélites , Polimorfismo Genético , Zantedeschia/genética , Marcadores Genéticos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
8.
Zhong Yao Cai ; 35(4): 648-50, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23019915

RESUMO

OBJECTIVE: To optimize the extraction technology of total triterpenoids from Hypodematium sinense. METHODS: With 5% vanillin-glacial acetic acid solution and 72% sulfuric acid as chromogenic agent and the content of total tripenoids as index,using single factor experiment and orthogonal test,the optimal extraction condition was determined. RESULTS: The optimal conditions were solid-liquid ratio 1:12, 60% ethanol concentration, and ultrasonic extraction time of 60 min at 60 degrees C. CONCLUSION: The extraction technology is feasible and can be used as extraction process of total triterpenoids from Hypodematium sinense.


Assuntos
Gleiquênias/química , Tecnologia Farmacêutica/métodos , Triterpenos/isolamento & purificação , Ultrassom , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/isolamento & purificação , Etanol/química , Componentes Aéreos da Planta/química , Solventes , Temperatura , Fatores de Tempo , Triterpenos/análise
9.
Cancer Lett ; 269(1): 101-10, 2008 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-18538471

RESUMO

Tyroservatide (YSV) is an active, low-molecular-weight polypeptide that has been shown to have antitumor effects on human hepatocellular carcinoma BEL-7402 cells in vitro and in vivo. Multi-drug resistance (MDR) represents a major obstacle to the success of cancer chemotherapy. To enhance the chemosensitivity of tumor cells, attention has been focused on MDR modulators. In this study, we evaluated the reversal effect of YSV on MDR, and explored its mechanism of action in vitro. Administration of YSV reversed the multi-drug resistance of human hepatocellular carcinoma BEL-7402/5-FU cells significantly. The intracellular accumulation of doxorubicin and Rhodamine-123 (Rh123) were increased, which implied that the function of the P-glycoprotein (P-gp) efflux pump was inhibited by YSV. Moreover, the mRNA and protein expression of multi-drug resistance gene (MDR1) were also decreased by YSV. We observe that lung-resistance protein (LRP) and multi-drug resistance-associated protein (MRP1) each contribute to MDR in BEL-7402/5-FU cells as well. The mRNA and protein expression of LRP were decreased by YSV. No significant change was observed in mRNA expression of MRP1. However, we observe that the MRP1 protein level was reduced after treatment with YSV. These data demonstrate that YSV effectively reverses MDR in BEL-7402/5-FU cells, and that its mechanism of action is associated with the down-regulation of MDR1, MRP1 and LRP expression, as well as the inhibition of P-gp function.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Oligopeptídeos/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Doxorrubicina/metabolismo , Resistencia a Medicamentos Antineoplásicos , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , RNA Mensageiro/análise , Rodamina 123/metabolismo , Partículas de Ribonucleoproteínas em Forma de Abóbada/genética
10.
Peptides ; 29(7): 1176-82, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18440669

RESUMO

Now peptides achieve distinct advantages over protein in biological application because of its quick and easy absorption, low power, and high activity. Some bioactive peptides had been developed to be used in the management of exercise-related disorders. In this study, we investigated whether the decapeptide CMS001 (Pro-Thr-Thr-Lys-Thr-Tyr-Phe-Pro-His-Phe) isolated from pig spleen had anti-fatigue effects. Male Balb/c mice were administered CMS001 (20 microg/(kgd)(-1) or 5 microg/(kgd)(-1) for 30 d, intraperitoneal injections) and tested in an exhaustive swim time task. In order to examine the mechanisms of CMS001 anti-fatigue effects, we analyzed liver glycogen stores, blood urea nitrogen (BUN) levels, lactic acid levels, ultrastructural integrity, and levels of both a free radical metabolite and an anti-oxidant enzyme. CMS001 treatment prolonged exhaustive swim time, increased liver glycogen levels, reduced BUN levels, and decreased accumulation of lactic acid in the blood, relative to mice injected with only saline. Examination of the ultrastructure of mitochondria and sarcoplasmic reticulum in skeletal and cardiac muscle of CMS001-treated and control mice revealed that CMS001 can reduce the damage to cardiac and skeletal muscle caused by an exhaustive swim challenge, such that the structure of most tissue specimens were normal in the peptide-treated group. Furthermore the free radical analysis after acute exercise indicated that CMS001 treatment decreased malondialdehyde (MDA) and increased superoxide dismutase (SOD) levels. The present findings indicate that the spleen-derived peptide CMS001 has anti-fatigue effects in mice, and further suggest that the mechanism may involve reduction of tissue damaging free radicals in muscle tissues.


Assuntos
Oligopeptídeos/farmacologia , Resistência Física/efeitos dos fármacos , Natação , Animais , Nitrogênio da Ureia Sanguínea , Ácido Láctico/sangue , Glicogênio Hepático/análise , Glicogênio Hepático/metabolismo , Masculino , Malondialdeído/sangue , Camundongos , Camundongos Endogâmicos BALB C , Músculo Esquelético/ultraestrutura , Miocárdio/ultraestrutura , Distribuição Aleatória , Organismos Livres de Patógenos Específicos , Superóxido Dismutase/sangue , Fatores de Tempo
11.
Zhonghua Zhong Liu Za Zhi ; 30(10): 725-8, 2008 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19173797

RESUMO

OBJECTIVE: To investigate the inhibitory effect of tyroservatide (YSV) on growth of hepatocellular carcinoma cells. METHODS: In vitro effects of YSV on five human hepatocellular carcinoma cell lines were assayed by MTS. In vivo effects of YSV on 5 human hepatocellular carcinoma cell lines were assayed by hollow fiber tumor model. RESULTS: After treatment with YSV at a dose of 0.1 approximately 1.6 mg/ml, the growth of the five cell lines was significantly inhibited in vitro compared with that of the control group (P < 0.05). Especially, YSL remarkably inhibited the growth of human hepatocellular carcinoma BEL-7402 cells, i.e. the cell growth was inhibited by 63.3% after treatment with YSL at 1.6 mg/ml. The hollow fiber tumor model demonstrated that YSL (320 microg x kg(-1) x d(-1) and 640 microg x kg(-1) x d(-1)) treatment significantly inhibited the in vivo growth of the five cancer cell lines compared with that in the saline control (P < 0.05). YSL showed the highest level of inhibition of human BEL-7402 hepatocellular carcinoma cells, with an inhibitory index of 53.1% at 320 microg x kg(-1) x d(-1). CONCLUSION: As a new method, hollow fiber assay may be used to evaluate the inhibitory effect of drugs on different tumor cells in vivo, rapidly, accurately and economically. Our results provide an instruction and evidence for clinical use of YSV.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/patologia , Oligopeptídeos/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Distribuição Aleatória
12.
Tohoku J Exp Med ; 212(3): 319-34, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17592219

RESUMO

Adenoid cystic carcinoma (ACC) is a common salivary gland malignancy characterized by slow but progressive clinical course, proclivity for hematogenous spread and perineural invasion (PNI) that exhibits inherent resistance to complete surgical resection, systemic chemotherapy and conventional radiotherapy. The molecular alterations that underlie its PNI are poorly characterized. We report the combined use of laser capture microdissection (LCM) and high-throughput cDNA microarray to monitor in vivo gene expression profile of salivary ACC and to correlate the profile with PNI. Consecutive section staining with hematoxylin & eosin was applied to 15 cancerous tissues, among which 6 were judged as PNI. Pure cancer cells adjacent to the nerve tracts from 6 cancerous tissues judged as PNI were laser captured, and pure cancer cells from the same 6 tumors distant from the nerve tracts were also procured. Total RNA was extracted, amplified and subjected to cDNA microarray-based expression analysis. The patterns of gene expression were verified by quantitative real-time PCR and immunohistochemistry. As to the result of 6 arrays, a total of 53 genes were identified as being 2-fold or more differentially expressed in PNI cancer cell group as compared to non-PNI cancer cell control. Out of the 53 genes found consistently differentially expressed, 38 were up-regulated and 15 down-regulated. The combined use of LCM and cDNA microarray analysis provides a powerful new approach to monitor the in vivo molecular events of PNI in salivary ACC. These identified novel genes deserve further investigations to elucidate their clinicopathological significance.


Assuntos
Carcinoma Adenoide Cístico/genética , Carcinoma Adenoide Cístico/patologia , Perfilação da Expressão Gênica , Neoplasias do Sistema Nervoso Periférico/genética , Neoplasias do Sistema Nervoso Periférico/patologia , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/patologia , Feminino , Humanos , Masculino , Microdissecção , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos
13.
Anticancer Drugs ; 18(4): 467-70, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17351399

RESUMO

The tripeptide tyroservatide (tyrosyl-seryl-valine, pTyr-Ser-Val-NH2) has been shown to have antitumor effects on experimental hepatocarcinoma. This study aimed to observe the effects of tyroservatide on other five human carcinomas: A549 (nonsmall cell lung carcinoma), BGC-823 (gastric cancer), MCF-7 (breast cancer), K562 (leukemia), A375 (melanoma) and two murine cancers: Lewis lung cancer and B16 (melanoma) in vivo. In vivo nude mice bearing xenografts of five different human tumors or C57BL/6 mice bearing xenografts of two different murine tumors were given daily intraperitoneal injections of tyroservatide or saline as controls, after tumor implantation. The inhibition of xenografts was determined by calculating the tumor volume and measuring tumor weight. Tyroservatide could significantly inhibit the growth of human lung carcinoma A549, human leukemia K562 and human melanoma A375 in nude mice (P<0.05). In addition, tyroservatide significantly inhibited the subcutaneous tumor growth of Lewis lung carcinoma and B16 melanoma (P<0.05). Tyroservatide, however, could not significantly suppress xenografts of BGC-823 and MCF-7 in nude mice (P>0.05). The results obtained indicate that tyroservatide exhibits different effects on different tumors, which will provide clinical applications guidance of tyroservatide as an anticancer drug.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Indicadores e Reagentes , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Transplante de Neoplasias , Transplante Heterólogo
14.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(6): 1002-6, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18182717

RESUMO

OBJECTIVE: To observe the effect of Krüppel-like factor 4 (KLF4) overexpression on heat stress-induced apoptosis of Raw264.7 macrophages. METHODS: The fragment containing full length mouse KLF4 cDNA coding sequence was inserted into the pcDNA3.1 vector and Raw264.7 macrophages were transfected with pcDNA3.1-KLF4 plasmids using lipofectamine.The expression of KLF4 was examined by Western blot in the Raw264.7 macrophages stably transfected with pcDNA3.1- KLF4 plasmids. Raw264.7 cells transfected with pcDNA3.1 and pcDNA3.1-KLF4 were exposed to heat stress (42 degrees C) for 1h and recovered at 37 degrees C for 12h. Flow cytometry, Hoechest 33258 staining assay, and DNA ladder assays were performed to assess the apoptosis. RESULTS: The KLF4 overexpressed Raw264.7 macrophages were established. After the heat stress, flow cytometry showed that apoptotic cells increased significantly in KLF4 overexpressed cells compared with the vector control; Hoechest 33258 staining was characterized with classical changes including apoptotic body, and nuclear condensation. Agarose gel electrophoresis showed that "DNA ladder" could be observed clearly. CONCLUSION: KLF4 overexpression can increase heat stress-induced apoptosis of Raw264.7 macrophages.


Assuntos
Apoptose/genética , Resposta ao Choque Térmico , Fatores de Transcrição Kruppel-Like/genética , Macrófagos/citologia , Animais , Linhagem Celular , Vetores Genéticos , Fator 4 Semelhante a Kruppel , Camundongos , Plasmídeos , Transfecção
15.
J Biol Chem ; 281(45): 33997-4008, 2006 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-16963447

RESUMO

We cloned a novel mouse cDNA, Mcpr1 (mouse cleft palate-related gene 1), between retinoic acid (RA)-treated murine embryonic palatal and control shelves by improved subtractive hybridization. Its transcript was identified by Northern blotting. The open reading frame encodes 132 amino acids and shows almost no identity to other genetic products. Mcpr1 expression could be detected extensively in adult mouse tissues and during murine embryonic development. It was identified to be significantly stimulated by RA in murine palatal shelves at embryonic day 12 and in palatal mesenchymal cells in vitro. We demonstrate that MCPR1 protein was localized primarily in the cytoplasm and could be synthesized and secreted by transfected COS-7 cells. Both the secretory and recombinant proteins of Mcpr1 inhibited proliferation of murine embryonic palatal mesenchymal cells and impeded the progression from the G1 to S phase in the cell cycle. The cells were prone to apoptosis after exposure to glutathione S-transferase-MCPR1. Furthermore, knockdown of MCPR1 protein levels by antisense oligodeoxynucleotides promoted progression of cells from the G1 to S phase and completely abolished the RA-induced block of the cell cycle from the G1 to S phase. These findings suggest that Mcpr1 might function as one of the RA-up-regulated genes involved in inhibiting cell proliferation during palatogenesis and RA-induced cleft palate by regulating proliferation and apoptosis of embryonic palatal mesenchymal cells and might even play a role in the development of many other organs.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proliferação de Células , Fissura Palatina/genética , Células-Tronco Mesenquimais/patologia , Palato/anormalidades , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Animais , Apoptose , Northern Blotting , Fissura Palatina/induzido quimicamente , Fissura Palatina/patologia , Clonagem Molecular , Feminino , Biblioteca Gênica , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Palato/efeitos dos fármacos , Palato/embriologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Técnica de Subtração , Tretinoína/toxicidade
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 31(3): 345-9, 2006 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16859120

RESUMO

OBJECTIVE: To observe the proliferation of SW480 cells exposed to different concentrations of CoCl2, and to examine the expression of hypoxiainducible factor-1 alpha (HIF-1alpha) and heme oxygenase-1 (HO-1) during hypoxia to explore the chemotherapy resistance effect and role of HIF-1alpha and HO-1. METHODS: Methyl thiazolyl tetrazolium (MTF) method was used to detect the proliferation of SW480 cells in the presence of fluorouracil (FU). RT-PCR was applied to examine the expression of HIF-1alpha and HO-1 mRNA in hypoxia. RESULTS: SW480 cells were proliferated at a slow rate, and had a strong resistance to FU with the increase of CoCl2. RT-PCR showed that the up-regulated expression of HIF-1alpha and HO-1 mRNA was consistent with the dose-effect curve and time-effect curve. CONCLUSION: The hypoxia induced by CoCl2 can inhibit the proliferation of SW480, and it can also decrease the sensitivity of the cell to FU. The mechanism is probably related to the up-regulated expression of HIF-1alpha and HO-1 mRNA.


Assuntos
Cobalto/farmacologia , Neoplasias do Colo/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluoruracila/farmacologia , Fator 1 Induzível por Hipóxia/biossíntese , Antimutagênicos/farmacologia , Hipóxia Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Heme Oxigenase-1/biossíntese , Heme Oxigenase-1/genética , Humanos , Fator 1 Induzível por Hipóxia/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 31(2): 167-73, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16706108

RESUMO

OBJECTIVE: To screen the inflammatory mediators genes regulated by HSF1, and explore the mechanism of downstream genes regulated by HSF1. METHODS: HSF-/- and HSF1+/+ mice were injected with 15 mg/kg LPS intraperitoneally (ip), respectively, and were treated as previous after HSR. The total RNA of lung tissues were extracted and filtrated by SuperArray gene Microarry. The promoter of candidate genes were analyzed by transcription element search software to search for heat shock element (HSE). Select the suppressor of cytokine signaling 3 (SOCS3) with HSE. Macrophage cells were stimulated with 400 ng/mL LPS, and were treated as previous after HSR, then the total RNA was extracted respectively. RT-PCR and northern blot assay were performed to detect the expression levels of SOCS3 mRNA. RESULTS: Fifteen genes were repressed by HSF1, including 9 genes with complete HSE. Eleven genes were accelerated by HSF1 possibly, including 8 genes with complete HSE. The promoter of SOCS3 gene contained one complete HSE. LPS stimulation obviously increased the levels of SOCS3 mRNA in macrophages of RAW264.7 mice, which was inhibited by HSR and over-expression of HSF1. CONCLUSION: HSR or HSF1 inhibits LPS induced expression of SOCS3 mRNA; HSF1 might inhibit LPS-induced expression of SOCS3 mRNA by binding to HSE in the promoter of SOCS3 gene.


Assuntos
Proteínas de Ligação a DNA/genética , Inflamação/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Fatores de Transcrição/genética , Animais , Proteínas de Ligação a DNA/farmacologia , Endotoxemia/induzido quimicamente , Endotoxemia/genética , Fatores de Transcrição de Choque Térmico , Proteínas de Choque Térmico/genética , Lipopolissacarídeos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Mutação , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/biossíntese , Fatores de Transcrição/farmacologia
18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 31(2): 174-7, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16706109

RESUMO

OBJECTIVE: To establish immortalized embryonic fibroblast lines in heat shock transcription factor 1 (HSF1) HSF1-/- and HSF1+/+ mice and to provide experimental models to study the function of HSF1. METHODS: A mammalian expression vector (pSV3neo) containing the SV40 large T antigen was used to transfect the HSF1-/- and HSF1+/+ mouse embryonic fibroblast using Lipofectamine 2000. Colonies were screened by G418 and expanded to immortalized cell lines. PCR was used to detect the integration of the large T antigen with genome in the mouse embryonic fibroblast. Expression of SV40 large T antigen gene in expanded cells was identified by RT-PCR. HSP70 expression was examined by Western blot in the embryonic fibroblast lines. RESULTS: The stable growth and serial propagation were observed in the HSF1-/- and HSF1+/+ cell lines for six months. The mRNA of SV40 T antigen gene expressed in the two cell lines. HSP70 expression could not be induced in the heat-treated HSF1-/- mouse embryo fibroblasts. CONCLUSION: The immortalized cells of HSF1+/+ and HSF1-/- mouse embryo fibroblasts are successfully established.


Assuntos
Antígenos Transformantes de Poliomavirus/farmacologia , Proteínas de Ligação a DNA/genética , Fibroblastos/citologia , Fatores de Transcrição/genética , Animais , Linhagem Celular , Embrião de Mamíferos , Feminino , Fatores de Transcrição de Choque Térmico , Masculino , Camundongos , Camundongos Knockout
19.
Int J Pharm ; 308(1-2): 100-6, 2006 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-16321487

RESUMO

Silybin is a main component in silymarin, which is an antihepatotoxic polyphenolic substance isolated from the milk thistle plant, Silybum marianum. A major problem in the development of an oral solid dosage form of this drug is the extremely poor aqueous solubility. In present work, the solubility of silybin in aqueous poly(ethylene glycol) 6,000 (PEG 6,000) solution at the temperature range from 293.15 to 313.15K was measured by a solid liquid equilibrium method. The aim of this study is to investigate the possible effect of poly(ethylene glycol) concentration and temperature on the solubility of the drug, and to reveal the solubilization capacity of the polymer for the drug. Experimental results reveal that the solubility of silybin increases with the increase both in PEG's concentration and temperature. With the increase in PEG's concentration, the transfer enthalpy and entropy for silybin from water to aqueous PEG solution increases first in a positive region, and then decreases to a negative region. The transfer enthalpy is lower than the entropy term. A modified Universal Quasi Chemical (UNIQUAC) model was used to correlate solubility data.


Assuntos
Polietilenoglicóis/química , Silybum marianum , Solventes/química , Modelos Químicos , Silibina , Silimarina/química , Solubilidade , Temperatura , Termodinâmica
20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 30(5): 515-20, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16320578

RESUMO

OBJECTIVE: To determine the characteristics of a novel gene Mip5 (GenBank accession number AY553870) and its expression under physiological and pathological conditions. METHODS: The characteristics of Mip5 were analyzed by bioinformatic programs including BLAST, spidey, psort, ClustalW and so on. RT-PCR was performed to detect Mip5 expression. RESULTS: Bioinformatic analysis showed that Mip5 gene lied in the 13th chromosome and contained 8 exons and 7 introns, its open reading frame contained 909 bp and its protein production was 302 amino acid residues including 6 kelth domains. Under normal conditions, MIP5 expressed abundantly in the heart, brain and kidney, but its expression could not be detected in the liver and muscle. Expression of Mip5 gene was increased significantly after ischemia-reperfusion compared with the sham groups, and reached its peak at 3 h and recovered at 12 h after the reperfusion. Conclusion Mip5 gene is a novel gene containing a putative open reading frame of 302 amino acids residues and may play an important role in rat cardiomyocytes suffering ischemia processing.


Assuntos
Cromossomos Humanos Par 13/genética , Isquemia Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/genética , Fases de Leitura Aberta/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , Humanos , Masculino , Dados de Sequência Molecular , Ratos
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