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1.
Cell Transplant ; 9(6): 857-65, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11202571

RESUMO

The objective of this study was to determine whether transfection of human islets with an adenovirus construct encoding an inhibitor of tumor necrosis factor (TNFi) was effective at limiting damage to beta cells induced by human peripheral blood leukocytes (huPBL). Human islets transfected with TNFi or control islets were transplanted under the kidney capsule of NOD-scid mice. After a 15-day engraftment period, half of the mice received injections of activated huPBL and half received buffer injections. Islet graft function was assessed by two different methods, both of which use a species-specific radioimmunoassay to determine human insulin. In some mice, insulin production following intraperitoneal glucose injection was determined in serum. In other mice, total graft insulin content was determined by acid ethanol extraction. Histochemical stains were performed on some kidneys at the termination of the experiment to evaluate graft presence, transgene expression, and huPBL infiltration. In huPBL injected mice, graft performance was maintained in mice whose grafts were transfected with TNFi but declined substantially in control groups with sham transfected or beta-galactosidase transfected islet grafts. Similar results were obtained using either glucose-stimulated insulin release or graft insulin content as a measure of graft survival. There was no significant difference in graft function between control groups receiving buffer injections, regardless of whether the islets had been transfected. Human leukocytes were found in all huPBL groups regardless of islet transfection status. We conclude that transfection of human islets with an adenovirus encoding TNFi protects beta cells from destruction induced by human leukocytes. The local production of TNFi does not prevent graft infiltration by leukocytes, only the destruction of grafts by the infiltrating leukocytes. These results raise the possibility that local expression of an inhibitor of the proinflammatory cytokine TNF-alpha may also prevent graft failure in clinical islet transplantation.


Assuntos
Transplante das Ilhotas Pancreáticas/imunologia , Transplante das Ilhotas Pancreáticas/métodos , Leucócitos/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia , Animais , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Humanos , Insulina/análise , Insulina/sangue , Rim/química , Antígenos Comuns de Leucócito/análise , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Baço/química , Transfecção
2.
Biochem J ; 295 ( Pt 3): 787-92, 1993 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8240293

RESUMO

Transport of lipids from the yolk to the tissues of the chick embryo is slow during the first 2 weeks of development, but increases abruptly during the last week. Evidence suggests that the lipid traverses the cytoplasm of the yolk-sac membrane before secretion as lipoprotein into the fetal circulation. Little is known about the cytoplasmic transport of lipid in avian systems, but recently the presence of sterol carrier protein 2 (SCP2) was reported in chicken liver. Here we examine the cells of yolk-sac membrane, liver and small intestine for the presence of this protein as a function of the time of embryonic development. The quantity of SCP2 present in the embryonic cells did not appear to correlate with the rate of lipid flux in these tissues. The abrupt appearance of a high-molecular-mass form of SCP2 was detected in small intestine shortly before hatching, but the significance of this protein is not clear. The presence of SCP2 in these tissues was also confirmed by immunocytochemical techniques. Similarly to SCP2 of mammalian cells, avian SCP2 is localized in both peroxisome-like structures and mitochondria. To a lesser extent it is associated with the endoplasmic reticulum.


Assuntos
Proteínas de Transporte/metabolismo , Intestino Delgado/embriologia , Fígado/embriologia , Proteínas de Plantas , Frações Subcelulares/metabolismo , Saco Vitelino/metabolismo , Animais , Western Blotting , Embrião de Galinha , Retículo Endoplasmático/metabolismo , Intestino Delgado/metabolismo , Intestino Delgado/ultraestrutura , Fígado/metabolismo , Fígado/ultraestrutura , Microcorpos/metabolismo , Microscopia Eletrônica , Mitocôndrias/metabolismo , Fatores de Tempo , Saco Vitelino/ultraestrutura
4.
Heredity (Edinb) ; 48(Pt 1): 35-44, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7042652

RESUMO

Populations of seaweed fly Coelopa frigida are polymorphic at three loci determining the enzymes peptidase-1 (Pep-1), alcohol dehydrogenase (Adh) and larval esterase-2 (Es-2). Alleles at these loci have been shown by others to be non-randomly associated with each other. In the present paper we report non-random associations between the Adh and Es-2 loci and inversions on chromosome I. The two common alleles Adh-B and D are in strong linkage disequilibrium with the alpha and beta inversions, but the Adh-A and C alleles are not so. The X and Y alleles at the Es-2 locus show weak, but still significant, associations with the inversions. We consider possible linkage relationships of the loci on the chromosomal arrangements, and discuss the hypothesis that they constitute part of a coadapted gene complex whose members code for functionally related enzymes.


Assuntos
Oxirredutases do Álcool/genética , Inversão Cromossômica , Dípteros/genética , Esterases/genética , Peptídeo Hidrolases/genética , Polimorfismo Genético , Animais , Cromossomos/ultraestrutura , Genes , Ligação Genética
6.
J Med Chem ; 19(6): 787-92, 1976 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-950647

RESUMO

A novel series of acidic cycloalkanoindoles comprising tetrahydrocarbazole-, cyclopentindole-, and cycloheptindole-1-acetic acids has been synthesized via the Fischer indolization between a phenylhydrazine and a 1-alkyl-2-oxocycloalkaneacetic acid ester. These compounds were evaluated, orally, for their capacities to decrease estabished adjuvant arthritis in rats. The most active compound of the series was 1-ethyl-8-n-propyl-1,2,3,4-tetrahydrocarbazole-1-acetic acid (AY-24 873),which had an ED50 of 1.1 +/- 0.2 mg/kg. AY-24 873 was also studied orally in rats for its effect on the acute inflammatory response in the carrageenin paw edema test. It was found that AY-24 873 was about ten times more active against the chromic than against the acute models of inflammation used.


Assuntos
Anti-Inflamatórios/síntese química , Carbazóis/síntese química , Indóis/síntese química , Animais , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Carbazóis/efeitos adversos , Carbazóis/uso terapêutico , Cicloeptanos/efeitos adversos , Cicloeptanos/síntese química , Cicloeptanos/uso terapêutico , Ciclopentanos/síntese química , Ciclopentanos/uso terapêutico , Edema/tratamento farmacológico , Indóis/efeitos adversos , Indóis/uso terapêutico , Ratos , Úlcera Gástrica/induzido quimicamente , Relação Estrutura-Atividade
7.
J Med Chem ; 18(2): 189-91, 1975 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1120985

RESUMO

The synthesis and antiinflammatory activities of a series of 23 novel 1,3,4,9-tetrahydropyrano[3,4-b]indole-1-alkanoic acids are described and some relationships between structure and activity are discussed. One of these compounds, 1,3,4,9-tetrahydro-1-propylpyrano[3,4-b]indole-1-acetic acid (prodolic acid, USAN), has been selected for further studies.


Assuntos
Anti-Inflamatórios/síntese química , Indóis/síntese química , Animais , Anti-Inflamatórios/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/uso terapêutico , Adjuvante de Freund , Ácidos Indolacéticos , Indóis/uso terapêutico , Espectroscopia de Ressonância Magnética , Conformação Molecular , Piranos/síntese química , Piranos/uso terapêutico , Ratos , Estereoisomerismo , Relação Estrutura-Atividade
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