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1.
Zhonghua Nei Ke Za Zhi ; 62(11): 1303-1310, 2023 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-37935496

RESUMO

Objective: To investigate the levels of sex hormone and fertility in female patients after hematopoietic stem cell transplantation (HSCT), as well as their correlation with conditioning regimens, and analyse the effect of hormone replacement therapy (HRT) in young women after HSCT. Methods: Retrospective case series study. The clinical data of 147 women who underwent HSCT in the First Affiliated Hospital of Soochow University from January 2010 to January 2021 were retrospectively analyzed. The sex hormone levels were measured and followed-up, and the survival, menstrual fertility and the use of HRT of the patients were also followed-up. The sex hormone levels were measured after transplantation, and the ovarian function was evaluated. Independent sample t test and χ2 test were used for comparison between the two groups. Results: The median age of the 147 patients was 26 (range, 10-45) years. Of them, 135 patients received allogeneic HSCT and 12 patients received autologous HSCT. Furthermore, 129 patients received myeloablative conditioning, and 18 patients received reduced conditioning dose. The median follow-up time was 50 months (range, 18-134 months). Five patients died of disease recurrence during follow-up. Of the 54 patients with subcutaneous injection of zoladex, three recovered menstruation spontaneously after transplantation, and all of them were myeloablative conditioning patients, one patient gave birth to twins through assisted reproductive technology. Ninety-three patients did not use zoladex before conditioning, two patients with aplastic anemia with non-myeloablative transplantation resumed menstruation spontaneously, and conceived naturally. The level of follicle stimulating hormone after transplantation in patients receiving myeloablative conditioning regimen was significantly higher than that in patients receiving reduced-dose conditioning regimen [(95.28±3.94) U/L vs. (71.85±10.72) U/L, P=0.039]. Among 147 patients, 122 patients developed premature ovarian failure, 83 patients received sex hormone replacement therapy after transplantation, and 76 patients recovered menstruation and improved endocrine function. Conclusions: The incidence of premature ovarian failure is high in female patients after HSCT, and patients have a chance at natural conception. Reducing the dose of conditioning regimen and the application of zoladex before transplantation can reduce ovarian of conditioning drugs. HRT after transplantation can partially improve the endocrine function of patients.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Insuficiência Ovariana Primária , Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Insuficiência Ovariana Primária/etiologia , Seguimentos , Gosserrelina , Prognóstico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hormônios Esteroides Gonadais , Condicionamento Pré-Transplante/efeitos adversos , Doença Enxerto-Hospedeiro/etiologia
3.
Comput Intell Neurosci ; 2020: 8834162, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908478

RESUMO

In the field of asset allocation, how to balance the returns of an investment portfolio and its fluctuations is the core issue. Capital asset pricing model, arbitrage pricing theory, and Fama-French three-factor model were used to quantify the price of individual stocks and portfolios. Based on the second-order stochastic dominance rule, the higher moments of return series, the Shannon entropy, and some other actual investment constraints, we construct a multiconstraint portfolio optimization model, aiming at comprehensively weighting the returns and risk of portfolios rather than blindly maximizing its returns. Furthermore, the whale optimization algorithm based on FTSE100 index data is used to optimize the above multiconstraint portfolio optimization model, which significantly improves the rate of return of the simple diversified buy-and-hold strategy or the FTSE100 index. Furthermore, extensive experiments validate the superiority of the whale optimization algorithm over the other four swarm intelligence optimization algorithms (gray wolf optimizer, fruit fly optimization algorithm, particle swarm optimization, and firefly algorithm) through various indicators of the results, especially under harsh constraints.


Assuntos
Algoritmos , Baleias , Animais , Entropia , Inteligência , Investimentos em Saúde
4.
J Food Sci ; 77(5): C546-50, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22510095

RESUMO

As one of the most effective methods to modify proteins, enzymatic hydrolysis is used widely in the preparation of wheat products in the food industry. During the same process, starch pasting occurs frequently. The effects of wheat protein hydrolysis with papain, pepsin, and trypsin on the pasting properties of 3 different kinds of flour were investigated in 5 concentrations. Results showed that the peak viscosity, trough, final, and integral area of pasting curve of these flours decreased with increasing enzymatic hydrolysis of protein, and decreased significantly with the increasing enzyme concentrations. Medium-gluten flour was the least sensitive to enzymatic activity and weak-gluten the most sensitive. Downtrends appeared with increasing papain and trypsin concentrations in the form of breakdown. Enzymes had no significant different effect on the peak times of strong- and medium-gluten flour, but prolonged peak time slightly in weak-gluten flour. The pasting time and temperature of strong- and medium-gluten flour were significantly increased in a concentration-dependent manner. However, there were no significant effects on the pasting times of weak-gluten flour. These results could supply a basis for utilization of enzymatic hydrolysis of wheat protein in food industry and for further studies into the interactions between hydrolyzed protein and starch in food or processing industries.


Assuntos
Farinha/análise , Glutens/análise , Glutens/metabolismo , Triticum/química , Triticum/enzimologia , Manipulação de Alimentos/métodos , Hidrólise , Papaína/metabolismo , Pepsina A/metabolismo , Amido/metabolismo , Temperatura , Tripsina/metabolismo , Viscosidade
5.
J Nanosci Nanotechnol ; 9(2): 1054-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19441454

RESUMO

Under the analysis of particle growth mechanism, the monodisperse colloidal silica abrasives for chemical mechanical planarization (CMP) slurry were synthesized by the modified ion-exchanged and hydrothermal step-polymerization process. After the colloidal silica with controllable size was synthesized, its microstructure, stability and CMP performance was characterized and tested by SEM, HRTEM, Zeta potential Analyzer and CMP tester. Results show that the spherical, high stable (Zeta potential: -52.8 mV) colloidal silica with controllable size was achieved. About its CMP performance, the polishing rate for silicon double-side CMP is increased to be 317 nm/min and the polished surface roughness (RMS) was reduced to 0.32 nm.

6.
J Pharm Biomed Anal ; 32(3): 523-9, 2003 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-14565557

RESUMO

In order to provide the equivalent of a human anti-human protein antibody as positive control in ELISAs, a goat-human antibody complex was created using chemical cross-linking. The resulting hybrid complex had a larger molecular size on HPLC and SDS-PAGE. In ELISA, the goat-human complex bound to human antigen and was detectable by a secondary anti-human conjugate. The method to make the hybrid complex is simple, cost-effective and can be used to make human-like antibodies to many human proteins.


Assuntos
Anticorpos/química , Animais , Cromatografia Líquida de Alta Pressão , Reagentes de Ligações Cruzadas , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulinas/análise , Albumina Sérica/imunologia
7.
J Cell Biochem ; 84(1): 27-38, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11746513

RESUMO

Polypeptide growth factors promote cellular proliferation by binding to specific plasma membrane-anchored receptors. This interaction triggers the phosphorylation of signal transducing molecules and the transcriptional activation of numerous genes. We have used a differential display approach to identify fibroblast growth factor (FGF)-1-inducible genes in murine NIH 3T3 fibroblasts. Here we report that one of these genes encodes ank, a type IIIa transmembrane protein reported to function in cells as an inorganic pyrophosphate transporter. FGF-1 induction of ank mRNA expression is first detectable at 2 h after growth factor addition and is dependent on de novo RNA and protein synthesis. Ank gene expression is also upregulated after treating quiescent fibroblasts with several other mitogenic agents (e.g., calf serum or platelet-derived growth factor-BB) or the tumor promoter phorbol 12-myristate 13-acetate. Furthermore, in comparison to parental NIH 3T3 cells, oncogene-transformed NIH 3T3 cells constitutively express elevated levels of ank mRNA. FGF-1 also increases ank gene expression in non-immortalized human embryonic lung fibroblasts. Finally, the murine and human ank genes are expressed in vivo in a tissue-specific manner, with highest levels of mRNA expression found in brain, heart, and skeletal muscle. These results indicate that ank is a growth factor-regulated delayed-early response gene in mammalian cells, and we propose that increased ank expression during cell cycle progression may be necessary to maintain proper intracellular pyrophosphate levels during conditions of high cellular metabolic activity.


Assuntos
Fator 1 de Crescimento de Fibroblastos/farmacologia , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Membrana/genética , Ésteres de Forbol/farmacologia , Células 3T3 , Animais , Carcinógenos/farmacologia , Linhagem Celular Transformada , DNA Complementar/análise , DNA Complementar/isolamento & purificação , Embrião de Mamíferos/metabolismo , Fibroblastos/metabolismo , Perfilação da Expressão Gênica/métodos , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Proteínas de Transporte de Fosfato , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Distribuição Tecidual
8.
Biol Trace Elem Res ; 81(3): 245-54, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11575681

RESUMO

Trace elements are involved in chronic liver diseases because these elements may have a direct hepatic toxicity or may be decreased as a consequence of the impaired liver function, particularly in patients with alcoholic cirrhosis and/or malnutrition. In this study, we determined plasma and erythrocytes trace elements in 50 inpatients with nonalcoholic chronic liver disease (11 with biopsy-proven chronic hepatitis, 39 with cirrhosis [16 in stage A according to Child-Pugh criteria, 23 Child B+C]), and in a control group of 10 healthy subjects by the proton induced x-ray emission method. The relationship between trace element concentration and the extent of liver damage, the nutritional status (by anthropometric evaluations), and various blood markers of oxidative stress--reduced glutathione, total lipoperoxides and malonyldialdehyde--was investigated. We found that cirrhotics had a significant decrease of Fe, Zn, Se, and GSH levels in the plasma and of GSH and Se in the erythrocytes with respect to the control and chronic hepatitis groups. GSH levels were related to the degree of liver damage; a significant direct correlation was observed among Se, Zn, and GSH plasma values and between GSH and Se in the erythrocytes. The trace element decrease was, on the contrary, independent of the degree of liver function impairment and only partially affected by the nutritional status. Data indicate that liver cirrhosis, even if not alcohol related, induces a decrease of Se and Zn and that, in these patients, an oxidative stress is present, as documented by the significant correlation between Se and GSH. The plasma Br level was higher in cirrhotics with respect to the control and chronic hepatitis groups.


Assuntos
Cirrose Hepática/sangue , Hepatopatias/sangue , Fígado/lesões , Estresse Oxidativo , Oligoelementos/sangue , Adolescente , Adulto , Idoso , Eritrócitos/metabolismo , Glutationa/sangue , Glutationa/metabolismo , Humanos , Ferro/sangue , Peróxidos Lipídicos/sangue , Malondialdeído/sangue , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Nutrição , Selênio/sangue , Raios X , Zinco/sangue
9.
Proc Natl Acad Sci U S A ; 98(21): 11847-8, 2001 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-11562459

RESUMO

Quantum computing is a quickly growing research field. This article introduces the basic concepts of quantum computing, recent developments in quantum searching, and decoherence in a possible quantum dot realization.

11.
Asian J Androl ; 3(1): 71-3, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11250798

RESUMO

AIM: To study the effect of ligustrum fruit on spermatogenesis and blood gonadal hormones in diabetic rats. METHODS: Experimental diabetes was induced in male Wistar rats with streptozotocin. Ligustrum fruit extract was given by gastric gavage at a dose of crude drug 30 g x kg(-1) x d(-1) for 110 days. The serum gonadadotropic hormones and testosterone were determined on d 60 and testicular histology examined on d 110. RESULTS: In the control diabetic rats, the seminiferous tubules were dilated and the spermatogenic cells irregularly arranged. Spermatogenesis was arrested with the number of spermatids highly reduced and spermatozoa not observed. In the treated rats, all types of spermatogenic cells were practically normal. The serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone levels were higher in the treated than in the control rats, but the difference was insignificant. CONCLUSION: In experimental diabetic rats, ligustrum fruit extract protects the damaging effect of experimental diabetes on spermatogenesis.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Hormônios Esteroides Gonadais/sangue , Extratos Vegetais/farmacologia , Espermatogênese/efeitos dos fármacos , Animais , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Medicina Tradicional Chinesa , Ratos , Ratos Wistar , Testosterona/sangue
12.
Am J Pathol ; 156(4): 1253-61, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10751351

RESUMO

Polypeptide growth factors stimulate mammalian cell proliferation by binding to specific cell surface receptors. This interaction triggers numerous biochemical responses including the activation of protein phosphorylation cascades and the enhanced expression of specific genes. We have identified several fibroblast growth factor (FGF)-inducible genes in murine NIH 3T3 cells and recently reported that one of them, the FGF-inducible 14 (Fn14) immediate-early response gene, is predicted to encode a novel, cell surface-localized type Ia transmembrane protein. Here, we report that the human Fn14 homolog is located on chromosome 16p13.3 and encodes a 129-amino acid protein with approximately 82% sequence identity to the murine protein. The human Fn14 gene, like the murine Fn14 gene, is expressed at elevated levels after FGF, calf serum or phorbol ester treatment of fibroblasts in vitro and is expressed at relatively high levels in heart and kidney in vivo. We also report that the human Fn14 gene is expressed at relatively low levels in normal liver tissue but at high levels in liver cancer cell lines and in hepatocellular carcinoma specimens. Furthermore, the murine Fn14 gene is rapidly induced during liver regeneration in vivo and is expressed at high levels in the hepatocellular carcinoma nodules that develop in the c-myc/transforming growth factor-alpha-driven and the hepatitis B virus X protein-driven transgenic mouse models of hepatocarcinogenesis. These results indicate that Fn14 may play a role in hepatocyte growth control and liver neoplasia.


Assuntos
Carcinoma Hepatocelular/genética , Regulação da Expressão Gênica , Expressão Gênica , Genes Precoces , Neoplasias Hepáticas/genética , Regeneração Hepática/genética , Proteínas de Membrana/genética , Receptores do Fator de Necrose Tumoral , Células 3T3 , Sequência de Aminoácidos/genética , Animais , Células Cultivadas , Mapeamento Cromossômico , DNA Complementar/genética , Humanos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Receptor de TWEAK
13.
J Biol Chem ; 274(46): 33166-76, 1999 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-10551889

RESUMO

The binding of polypeptide growth factors to their appropriate cell surface transmembrane receptors triggers numerous biochemical responses, including the transcriptional activation of specific genes. We have used a differential display approach to identify fibroblast growth factor-1-inducible genes in murine NIH 3T3 cells. Here, we report that the fibroblast growth factor-inducible-14 (Fn14) gene is a growth factor-regulated, immediate-early response gene expressed in a developmental stage- and adult tissue-specific manner in vivo. This gene, located on mouse chromosome 17, is predicted to encode an 129-amino acid type Ia membrane protein with no significant sequence similarity to any known protein. We have used two experimental approaches, direct fluorescence microscopy and immunoprecipitation analysis of biotinylated cell surface proteins, to demonstrate that Fn14 is located on the plasma membrane. To examine the biological consequences of constitutive Fn14 expression, we isolated NIH 3T3 cell lines expressing variable levels of epitope-tagged Fn14 and analyzed their phenotypic properties in vitro. These experiments revealed that Fn14 expression decreased cellular adhesion to the extracellular matrix proteins fibronectin and vitronectin and also reduced serum-stimulated cell growth and migration. These results indicate that Fn14 is a novel plasma membrane-spanning molecule that may play a role in cell-matrix interactions.


Assuntos
Proteínas de Membrana/genética , Receptores do Fator de Necrose Tumoral , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Adesão Celular/genética , Divisão Celular/genética , Movimento Celular/genética , Mapeamento Cromossômico , Clonagem Molecular , Fator de Crescimento Epidérmico/genética , Matriz Extracelular/metabolismo , Fator 1 de Crescimento de Fibroblastos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hemaglutininas/genética , Hibridização In Situ , Proteínas de Membrana/química , Camundongos , Microscopia de Fluorescência , Mitógenos/farmacologia , Dados de Sequência Molecular , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/genética , Receptor de TWEAK , Transfecção
14.
J Trace Elem Med Biol ; 13(1-2): 51-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10445218

RESUMO

We evaluated the effect of one year of supplementation with iron plus zinc (12 mg/day of Fe+++ and 12.5 mg/day of Zn++), zinc alone (12.5 mg/day of Zn++) and placebo on growth and on the iron, zinc, copper and selenium tissue contents in 30 well-selected children of short stature (16 M and 14 F; 4-11 years old). Before and after supplementation, we measured the concentrations of iron, transferrin, ferritin, zinc and copper in serum, of zinc in erythrocytes and leukocytes, and of zinc, copper and selenium in hair, as well as glutathione peroxidase activity in erythrocytes. Before supplementation, ferritin and serum, erythrocyte and hair zinc contents were significantly lower than in age-matched controls, while the other measured indices were in the normal range. Iron plus zinc supplementation caused an improvement in growth rate in all subjects, i.e., the median Z-score increased from -2.22 +/- 0.45 to -0.64 +/- 0.55; (p < 0.01). In the zinc-supplemented group, only the subjects whose ferritin levels were higher than 20 ng/L before supplementation showed a similar improvement of growth rate. Iron plus zinc supplementation could be a reasonable treatment in short, prepubertal children affected by marginal zinc and iron deficiency.


Assuntos
Estatura , Suplementos Nutricionais , Ferro/administração & dosagem , Oligoelementos/análise , Zinco/administração & dosagem , Determinação da Idade pelo Esqueleto , Antropometria , Criança , Pré-Escolar , Cobre/análise , Cobre/sangue , Eritrócitos/química , Feminino , Ferritinas/sangue , Glutationa Peroxidase/sangue , Cabelo/química , Humanos , Masculino , Selênio/análise , Zinco/análise , Zinco/sangue
15.
J Trace Elem Med Biol ; 11(3): 158-61, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9442462

RESUMO

The relationships between chronic liver diseases and trace element (TE) contents are debated. Particularly, no defined data are available about the TE levels in viral liver disease patients with or without malnutrition. In this study we evaluated blood and plasma levels of various trace elements in patients with HCV-related chronic liver disease, at different stages of liver damage (8 patients with chronic hepatitis and 32 with liver cirrhosis) with or without malnutrition. We also studied 10 healthy volunteers as control group. We found that cirrhotic subjects had a significant decrease of blood levels of Zn and Se, independently on the nutritional status, whereas plasma levels of Fe were significantly reduced only in malnourished cirrhotic patients. Our data indicate that liver impairment is the main cause of the blood decrease of Se and Zn levels in patients with non alcoholic liver disease, whereas the malnutrition affects Fe levels only.


Assuntos
Hepatopatias/sangue , Oligoelementos/sangue , Adolescente , Adulto , Idoso , Cromo/sangue , Doença Crônica , Cobre/sangue , Feminino , Humanos , Ferro/sangue , Cirrose Hepática/sangue , Hepatopatias/complicações , Masculino , Manganês/sangue , Pessoa de Meia-Idade , Distúrbios Nutricionais/sangue , Distúrbios Nutricionais/complicações , Rubídio/sangue , Selênio/sangue , Zinco/sangue
16.
Biochem J ; 319 ( Pt 1): 9-12, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8870641

RESUMO

Polypeptide growth factors promote cell-cycle progression in part by the transcriptional activation of a diverse group of specific genes. We have used an mRNA differential-display approach to identify several fibroblast growth factor (FGF)-1 (acidic FGF)-inducible genes in NIH 3T3 cells. Here we report that one of these genes, called FGF-regulated (FR)-3, is predicted to encode G/T mismatch-binding protein (GTBP), a component of the mammalian DNA mismatch correction system. The murine GTBP gene is transiently expressed after FGF-1 or calf serum treatment, with maximal mRNA levels detected at 12 and 18 h post-stimulation. FGF-1-stimulated NIH 3T3 cells also express an increased amount of GTBP as determined by immunoblot analysis. These results indicate that elevated levels of GTBP may be required during the DNA synthesis phase of the cell cycle for efficient G/T mismatch recognition and repair.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/biossíntese , Fator 1 de Crescimento de Fibroblastos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células 3T3 , Sequência de Aminoácidos , Animais , DNA Complementar , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Eletroforese em Gel de Poliacrilamida , Humanos , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Análise de Sequência de DNA
17.
Circ Res ; 79(2): 263-70, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8756003

RESUMO

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a vascular smooth muscle cell (SMC) mitogen and chemotactic factor that is expressed by endothelial cells, SMCs, monocytes/macrophages, and T lymphocytes. Both the membrane-anchored HB-EGF precursor and the secreted mature HB-EGF protein are biologically active; thus, HB-EGF may stimulate SMC growth via autocrine, paracrine, and juxtacrine mechanisms. In the present study, we report that HB-EGF treatment of serum-starved at aortic SMCs can induce fibroblast growth factor (FGF)-2 (basic FGF) gene expression but not FGF-1 (acidic FGF) gene expression. Increased FGF-2 mRNA expression is first detectable at 1 hour after HB-EGF addition, and maximal FGF-2 mRNA levels, corresponding to an approximately 46-fold level of induction, are present at 4 hours. The effect of HB-EGF on FGF-2 mRNA levels appears to be mediated primarily by a transcriptional mechanism and requires de novo synthesized proteins. HB-EGF induction of FGF-2 mRNA levels can be inhibited by treating cells with the anti-inflammatory glucocorticoid dexamethasone or the glycosaminoglycan heparin. Finally, Western blot analyses indicate that HB-EGF-treated SMCs also produce an increased amount of FGF-2 protein. These results indicate that HB-EGF expressed at sites of vascular injury or inflammation in vivo may upregulate FGF-2 production by SMCs.


Assuntos
Aorta/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Músculo Liso Vascular/metabolismo , Animais , Aorta/citologia , Northern Blotting , Western Blotting , Células Cultivadas , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Dexametasona/farmacologia , Fator 2 de Crescimento de Fibroblastos/genética , Heparina/farmacologia , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Peptídeos e Proteínas de Sinalização Intercelular , Cinética , Músculo Liso Vascular/citologia , Concentração Osmolar , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos WKY , Transcrição Gênica/efeitos dos fármacos
18.
Zhongguo Zhong Yao Za Zhi ; 19(10): 611-2, 639, 1994 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-7873081

RESUMO

Three compounds were isolated from the flower of Lilium devidii. On the basis of chemical reaction, UV, MS, 1HNMR and 13CNMR spectral data, they were identified as beta-sitosterol, stigmasterol and emodin. These compounds are obtained from the plant for the first time.


Assuntos
Medicamentos de Ervas Chinesas/química , Emodina/isolamento & purificação , Sitosteroides/isolamento & purificação , Estigmasterol/isolamento & purificação
19.
Protein Eng ; 7(8): 1017-26, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7809028

RESUMO

Single-chain Fv proteins are known to aggregate and form multimeric species. We report here that these molecules represent a new class of molecular assembly, which we have termed multivalent Fvs. Each binding site in a multivalent Fv comprises the variable light-chain (VL) domain from a single-chain Fv, and the variable heavy-chain (VH) domain from a second single-chain Fv. Each single-chain Fv in a multivalent Fv is part of two binding sites. We have characterized the multivalent forms of the 4-4-20, CC49 and B6.2 sFvs. The degree of multivalent Fv formation is linker-dependent. Multivalent Fvs cannot form in the absence of an intact linker. Multivalent Fvs can be stabilized by their antigen. The conversion between different forms of the multivalent Fvs can be catalyzed by disassociating agents such as 0.5 M guanidine hydrochloride with 20% ethanol. Multivalent Fvs have significantly different stabilities depending on the specific variable domains from which they are constructed. Two models have been proposed for the structure of a multivalent Fv. We have tested each model by attempting to produce a heterodimer from the anti-fluorescein 4-4-20 and anti-tumor CC49 variable regions. We successfully produced a 4-4-20/CC49 heterodimer that comprises two mixed sFvs. The first mixed sFv is composed of the 4-4-20 VL domain, a 12 residue linker and the CC49 Vh domain. The second mixed sFv is composed of a CC49 VL domain, a 12 residue linker and the 4-4-20 VH domain. The 4-4-20/CC49 heterodimer bound both fluorescein and the tumor-associated glycoprotein-72 antigen. These results support a VH/VL 'rearrangement' model in which each variable domain of a multivalent Fv binding site comes from a different polypeptide chain.


Assuntos
Especificidade de Anticorpos , Fragmentos de Imunoglobulinas/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Cadeias Leves de Imunoglobulina/imunologia , Região Variável de Imunoglobulina/imunologia , Animais , Antígenos de Neoplasias/metabolismo , Carcinoma , Neoplasias do Colo , Escherichia coli/genética , Feminino , Fluoresceína , Fluoresceínas/metabolismo , Glicoproteínas/metabolismo , Imunoensaio , Fragmentos de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Camundongos , Camundongos Nus , Modelos Imunológicos , Neoplasias Experimentais , Ligação Proteica , Engenharia de Proteínas , Proteínas Recombinantes/imunologia , Solubilidade
20.
Protein Eng ; 6(8): 989-95, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8309948

RESUMO

The effects of linker length on binding affinity and degree of aggregation have been examined in the antifluorescein 4-4-20 and anticarcinoma CC49 single-chain Fvs. Longer linkers in the antifluorescein sFvs have higher affinities for fluorescein and aggregate less. A proteolytically susceptible site between Lys8 and Ser9, in the previously reported 212 linker has been identified. A new linker sequence, 218 (GSTSGSGKPGSGEGSTKG) was designed in which a proline was placed at the C-terminal side of the proteolytic clip site in the 212 linker. The CC49 sFv containing the 218 linker showed reduced aggregation and was found to be more stable to proteolysis in vitro, when compared to the CC49/212 sFv. The CC49 sFv with the longer 218 linker had higher affinity than CC49/212 sFv. An aggregated CC49/212 sFv sample had higher affinity than CC49/218 sFv. The CC49/218 and CC49/212 sFvs had similar blood clearances in mice, while the aggregated CC49/212 sFv remained in circulation significantly longer. In mice bearing LS-174T human colon carcinoma xenografts, the CC49/218 sFv showed higher tumor uptake than the CC49/212 sFv and lower tumor uptake than the aggregated CC49/212 sFv. The higher tumor uptake of the CC49/218 is most likely a result of its higher resistance to proteolysis. The higher affinity and higher tumor uptake of the aggregated CC49/212 sFv are most likely due to the repetitive nature of the TAG-72 antigen and the higher avidity of multivalent aggregates. When the sFvs were radiolabeled with a lutetium-chelate the CC49/218 sFv showed a lower accumulation in the liver and spleen compared to the aggregated CC49/212 sFv.


Assuntos
Anticorpos Monoclonais/genética , Antígenos de Neoplasias/imunologia , Glicoproteínas/imunologia , Fragmentos de Imunoglobulinas/genética , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/metabolismo , Afinidade de Anticorpos , Antígenos de Neoplasias/metabolismo , Ligação Competitiva , Clonagem Molecular , Glicoproteínas/metabolismo , Fragmentos de Imunoglobulinas/metabolismo , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Radioimunoensaio , Distribuição Tecidual
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