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1.
J Fish Biol ; 79(4): 1068-75, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21967590

RESUMO

Radio-tagged adult Pacific lamprey Entosphenus tridentatus held in a raceway with Plexiglas-lined walls and bottom healed more slowly and retained sutures longer than fish held in an all-concrete raceway or one with Plexiglas walls and a cobble-lined bottom. On all substrata, healing depended on when sutures were lost, and fish that lost their sutures in <14 days post-surgery healed faster than those that kept sutures longer. Long-term suture retention led to tissue trauma, infection and poor survival.


Assuntos
Lampreias/fisiologia , Cicatrização/fisiologia , Sistemas de Identificação Animal/normas , Animais , Abrigo para Animais/normas , Rios , Infecção da Ferida Cirúrgica/mortalidade , Infecção da Ferida Cirúrgica/veterinária , Análise de Sobrevida , Suturas/veterinária
2.
Biochim Biophys Acta ; 743(1): 186-94, 1983 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-6824699

RESUMO

Interactions between a monoamine oxidase (monoamine: oxygen oxidoreductase deaminating, EC 1.4.3.4) obtained from rat liver cytosol by high speed centrifugation and a biologically active, spin labeled analog of amphetamine have been analyzed. The acetylenic monoamine oxidase inhibitors, pargyline and clorgyline, have been used to modulate the binding of spin labeled amphetamine. Broadening of electron spin resonance lines induced by immobilization of the probe on binding has been used to determine the concentration of bound probe. Pargyline was found to inhibit binding of spin labeled amphetamine by cytosolic monoamine oxidase. Bound spin labeled amphetamine was also displaceable by pargyline. In contrast, clorgyline enhanced the binding of spin labeled amphetamine to the cytosolic monoamine oxidase preparation. Inhibition or enhancement of amphetamine binding was very rapid and occurred during the reversible stage of interaction between the enzyme and the acetylenic compounds.


Assuntos
Anfetaminas , Clorgilina/farmacologia , Fígado/enzimologia , Monoaminoxidase/metabolismo , Pargilina/farmacologia , Propilaminas/farmacologia , Marcadores de Spin/farmacologia , Anfetamina , Animais , Citosol/enzimologia , Cinética , Masculino , Ligação Proteica , Ratos , Ratos Endogâmicos
3.
J Invest Dermatol ; 64(5): 349-56, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-167079

RESUMO

Electron spin resonance spectroscopy has been used to demonstrate that the phototoxic antimalarial drug, 6,8-dichloro-2-phenyl-a-2-piperidnylquinolinemethanol (WR 7930), when irradiated with long-wave ultraviolet (UV) light (lambda greater than 320 nm) while held in a glassy matrix at 73 degrees K, enters a triplet state and releases hydrogen atoms in its environment. The steady-state concentration of triplet WR 7930 molecules and of hydrogen atoms is reduced 2 to 3 times when mercaptoethylamine (MEA) is also present in the UV-irradiated glass. Organosulfur radicals form on MEA while hydrogen atoms and triplet-state molecules are reduced in number. Hydrogen atoms and triplet WR 7930 molecules are considered as mediators of the phototoxicity of the antimalarial drug. Thus, hydrogen atom scavanging and chemical quenching of the triplet state are possible mechanisms by which protection against phototoxic effects could be gained. Protection is demonstrated in mice receiving 20 mg per kg WR 7930 intraperitoneally and exposed to long-wave UV for 20 hr when the radioprotective aminothiol-forming compound, 2-(3-aminopropylamino) ethyl dihydrogen phosphorothioate (WR 2721), is administered at 400 mg per kg immediately before irradiation. When no protective drug is administered concurrently, WR 7930 administration results in intense erythema, edema, and eventual necrosis of ear tissues.


Assuntos
Antimaláricos/toxicidade , Mercaptoetilaminas/farmacologia , Transtornos de Fotossensibilidade/induzido quimicamente , Quinolinas/toxicidade , Protetores contra Radiação/farmacologia , Raios Ultravioleta , Animais , Antimaláricos/efeitos da radiação , Fenômenos Químicos , Química , Diaminas/farmacologia , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância de Spin Eletrônica , Eritema/induzido quimicamente , Feminino , Radicais Livres , Hidrogênio/farmacologia , Camundongos , Camundongos Endogâmicos , Necrose , Compostos Organotiofosforados/farmacologia , Piperidinas/efeitos da radiação , Piperidinas/toxicidade , Quinolinas/efeitos da radiação , Efeitos da Radiação
4.
J Immunol Methods ; 9(2): 165-70, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1206228

RESUMO

A new sensitive immunoassay procedure is described for quantitative detection of glycolipids and other lipids in aqueous media. As with other immunoassays specific antiserum is first reacted with the free lipid hapten. The amount of antibody activity remaining is measured by assaying the release, in the presence of complement, of spin label marker from liposomes containing the same lipid hapten. Using this method, 2.6 pmol of aqueous Forssman hapten was detected, and the sensitivity could be increased further.


Assuntos
Glicolipídeos/análise , Lipossomos , Reações Antígeno-Anticorpo , Antígeno de Forssman/análise , Glicolipídeos/imunologia , Imunoensaio/métodos
5.
Cancer Res ; 46(10): 5451, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3756893
18.
Biophys J ; 16(11): 1245-55, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-184858

RESUMO

Morphine, spin labeled on the 3- or 6-position has been used as the opiate ligand in a study of the time course of stereospecific opiate binding to intact synaptosomes isolated from non-cerebellar rat brain. The broadening of electron spin resonance lines induced by immobilization of the ligand on binding has been used to determine the concentration of bound opiate. The stereospecificity of the reaction was measured by comparing ligand binding in the presence of thousand-fold molar excesses of dextrorphan or levorphanol. Using both static and flow techniques, the binding process has been continuously monitored at times greater than 4.8 s after mixing spin labeled morphine with synaptosomes. It is shown that for this ligand and receptor preparation, binding takes place primarily during a delayed, abrupt process whose rate and time of onset are temperature dependent and reflect the presence of added opiate agonist or antagonist.


Assuntos
Receptores Opioides , Animais , Química Encefálica , Espectroscopia de Ressonância de Spin Eletrônica , Técnicas In Vitro , Ratos , Sinaptossomos
19.
Biochem J ; 146(1): 223-9, 1975 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-167714

RESUMO

1. The metabolic role of hepatic NAD-linked glycerol 3-phosphate dehydrogenase (EC 1.1.1.8) was investigated vis-a-vis glyceride synthesis, glyceride degradation and the maintainence of the NAD redox state. 2. Five-week-old chickens were placed on five dietary regimes: a control group, a group on an increased-carbohydrate-lowered-fat diet, a group on a high-fat-lowered-carbohydrate diet, a starved group and a starved-refed group. In each group the specific activity (mumol/min per g wet wt. of tissue) of hepatic glycerol 3-phosphate dehydrogenase was compared with the activities of the beta-oxoacyl-(acyl-carrier protein) reductase component of fatty acid synthetase, glycerol kinase (EC 2.7.1.30) and lactate dehydrogenase (EC 1.1.1.27). 3. During starvation, the activities of glycerol 3-phosphate dehydrogenase, glycerol kinase and lactate dehydrogenase rose significantly. After re-feeding these activities returned to near normal. All three activities rose slightly on the high-fat diet. Lactate dehydrogenase activity rose slightly, whereas those of the other two enzymes fell slightly on the increased-carbohydrate-lowered-fat diet. 4. The activity of the beta-oxoacyl-(acyl-carrier protein) reductase component of fatty acid synthetase, a lipid-synthesizing enzyme, contrasted strikingly with the other three enzyme activities. Its activity was slightly elevated on the increased-carbohydrate diet and significantly diminished on the high-fat diet and during starvation. 5. The changes in activity of the chicken liver isoenzyme of glycerol 3-phosphate dehydrogenase in response to dietary stresses suggest that the enzyme has an important metabolic role other than or in addition to glyceride biosynthesis.


Assuntos
Carboidratos da Dieta/metabolismo , Glicerídeos/metabolismo , Glicerolfosfato Desidrogenase/metabolismo , Fígado/enzimologia , Animais , Galinhas , Ácido Graxo Sintases/análise , Glicerol Quinase/análise , L-Lactato Desidrogenase/análise , Fígado/metabolismo , NAD , Inanição
20.
Biophys J ; 15(11): 1125-39, 1975 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1201330

RESUMO

Morphine spin labeled on the phenolic hydroxy group has been prepared using commercially available reagents and characterized by thin layer chromatography, mass spectroscopy, and electron spin resonance spectroscopy. It has been shown that morphine modified in this way retains some opiate activity, does not pass through the blood-brain barrier, and specifically binds to isolate rat brain synaptosomes. Spin labeled morphine has been shown to be an effective biophysical probe complementing radioactive tracer techniques in the study of the narcotic receptor site.


Assuntos
Encéfalo/metabolismo , Morfina/metabolismo , Receptores de Droga , Sinaptossomos/metabolismo , Animais , Sítios de Ligação , Camundongos , Marcadores de Spin
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