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1.
Biochim Biophys Acta ; 766(2): 375-85, 1984 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-6235853

RESUMEN

Energy transduction in an ATPase complex (complex V) has been studied in two reactions catalyzed by this system, i.e., ATP-dependent spectral shift of oxonol VI, and ATP-Pi exchange activity. Aurovertin alone inhibits 50% of the oxonol shift at 2 microM, and no further inhibition occurs at up to 12 microM. In combination with even weakly effective uncouplers, 4 microM aurovertin fully abolishes the oxonol response. No such effects are observed in the presence of oligomycin and uncouplers. No pH gradient is detectable by quenching of 9-amino-6-chloro-2-methoxyacridine; and nigericin is without effect on the oxonol response. Valinomycin is inhibitory even in the absence of added potassium, due to ammonium ions introduced during the purification steps. Thiocyanate inhibits the dye response by only 10-27%, depending on the preparation. The extent of the oxonol response depends on the ATP/ADP ratio rather than the phosphorylation potential. The dye response in the ATPase complex is 4-7-times less sensitive to bile salts than in submitochondrial particles. The inhibition by cardiolipin can be reversed by the addition of phospholipids. The possibility is discussed that the oxonol response in the ATPase complex reflects, at least in part, a more local, ATP-dependent and energy-related process.


Asunto(s)
Colorantes Fluorescentes , Isoxazoles , Mitocondrias/fisiología , ATPasas de Translocación de Protón Mitocondriales , Oxazoles , ATPasas de Translocación de Protón/metabolismo , Animales , Ácidos y Sales Biliares/farmacología , Sistema Libre de Células , Ionóforos/farmacología , Fosfolípidos/farmacología , ATPasas de Translocación de Protón/antagonistas & inhibidores , Reactivos de Sulfhidrilo/farmacología
2.
J Clin Oncol ; 14(9): 2435-43, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8823321

RESUMEN

PURPOSE: Late solid tumors (STs) are a significant cause of morbidity and mortality in long-term survivors of Hodgkin's disease. To investigate the carcinogenic potential of two different therapeutic approaches, we measured the relative risk (RR) of STs in patients with early-stage disease cured after primary full-dose (approximately 40 Gy) radiation therapy (RT) and in patients with advanced disease who were treated with chemotherapy followed by low-dose (15 to 30 Gy) involved-field radiation (CMT). PATIENTS AND METHODS: Because therapy-induced STs generally begin after a latency period of 5 to 10 years, we restricted our analysis to patients treated before 1986 who achieved durable remissions. Patients who required salvage chemotherapy or who died of Hodgkin's disease were excluded from analysis. The RR of STs was calculated by dividing the observed number of cases by the expected number in a matched population from the Connecticut Tumor Registry. The actuarial incidence of STs was also measured. RESULTS: A total of 197 patients formed the RT group and 116 the CMT group. The median follow-up period in the RT group was 12.8 years, versus 13.5 years in the CMT group. The overall RR of STs in the CMT group was 1.5 (95% confidence interval [CI], 0.6 to 3.5; P = .122). There were no cases of lung or breast cancer. In the RT group, the overall RR of STs was 3.3 (95% CI, 2.0 to 5.3; P < .001). There were seven cases of lung cancer (RR = 10.8; 95% CI, 5.3 to 22.2; P < .001) and two cases of breast cancer (RR = 2; 95% CI, 0.6 to 7.4; P = .07). All six benign tumors occurred in the RT group. CONCLUSION: In patients cured by initial treatment for Hodgkin's disease, RT was associated with a statistically significant increase in STs, particularly lung cancer. CMT was not associated with a significant increase in STs. These data may have important implications for the design of newer therapies for early-stage Hodgkin's disease.


Asunto(s)
Enfermedad de Hodgkin/terapia , Neoplasias Primarias Secundarias/etiología , Análisis Actuarial , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Estudios de Seguimiento , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/etiología , Radioterapia/efectos adversos , Dosificación Radioterapéutica , Radioterapia Adyuvante , Factores de Riesgo
3.
Thromb Haemost ; 56(2): 225-8, 1986 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-3810557

RESUMEN

This study was performed to estimate appropriate dosages of two low molecular weight heparins (LMWH) for clinical trials on subcutaneous perioperative thrombosis prophylaxis. Anticoagulatory activities and platelet function were investigated after single doses of two LMWH and of unfractionated sodium heparin (UFH) in 24 healthy individuals. Twelve subjects received subcutaneous injections of 1000, 1500, and 2500 i.u. (aPTT) of LMHW 1, and the other 12 received LMWH 2 at same dosages. The following parameters were determined before 30 min, 1 h, 90 min, 2 h, 3 h, 4 h, 6 h, 8 h, and 10 h after either LMWH or 5000 i.u. (aPTT) UFH: aPTT, thrombin time, anti-Xa activity (S 2222, Coatest heparin), and anti-IIa activity (Chromozym TH). Bleeding time, platelet count, and adrenalin-, collagen-, and ADP-induced platelet aggregation were assessed before and 3 h after administration. After application of 1500 i.u. LMWH 1 and LMWH 2, the anti-Xa and anti-IIa levels were already significantly higher than after 5000 i.u. UFH. 2500 i.u. LMWH 1 and LMWH 2 evoked significantly greater prolongations of aPTT and thrombin time values than did 5000 i.u. UFH. This was not the case after 1000 and 1500 i.u. LMWH. The half-lives of anticoagulatory effects after LMWH were markedly longer than after UFH. Platelet function was not altered by any of the heparins tested. Our results indicate that LMWH cause anticoagulatory effects in vivo that cannot be predicted by in vitro studies and that the appropriate single dosages of LMWH in subcutaneous perioperative thrombosis prophylaxis have to be estimated by dosage determinations in healthy subjects.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Heparina , Adulto , Animales , Pruebas de Coagulación Sanguínea , Relación Dosis-Respuesta a Droga , Heparina/administración & dosificación , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Peso Molecular , Relación Estructura-Actividad , Porcinos
4.
Thromb Haemost ; 56(3): 353-9, 1986 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-3105109

RESUMEN

Factor VIII:C recovery and half-life was measured in 16 hemophilia A patients under comprehensively standardized conditions. Each patient received the same lot of a steam-treated high purity FVIII concentrate at a dose of 19-33 U/kg body weight. A comparison was made between the one-stage assay, the two-stage assay and a chromogenic substrate test for FVIII:C determination using a FXa-sensitive chromogenic substrate. Factor VIII:C potency of the administered FVIII concentrate was measured using calibration curves derived from a concentrate standard and FVIII:C plasma levels were read from calibration curves derived from a plasma standard. The chromogenic assay showed a good reproducibility at FVIII:C levels between 0.015 and 0.50 U/ml. The FVIII:C recoveries calculated from the results of the one-stage assay, the two-stage assay and the chromogenic substrate test were 109 +/- 20, 92 +/- 14 and 81 +/- 11% (mean +/- SD), respectively. The elimination half-lives of FVIII:C were calculated by non-linear least square analysis using a modified computerized Gauss-Newton algorithm. The half-lives calculated from the FVIII:C plasma levels measured by the one-stage assay, the two-stage assay and the chromogenic test were 23.8 +/- 6.4, 22.2 +/- 5.7 and 17.1 +/- 4.8 h (mean +/- SD), respectively. No previous study has reported such long half-life values. Our findings indicate that measurements of recoveries and half-lives by the chromogenic FVIII:C assay and by computerized non-linear least square analysis allow the possibility of individualized FVIII replacement therapy.


Asunto(s)
Factor VIII/sangre , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Adolescente , Adulto , Niño , Compuestos Cromogénicos , Computadores , Factor VIII/administración & dosificación , Semivida , Hemofilia A/sangre , Calor , Humanos , Infusiones Intravenosas , Métodos
5.
DNA Seq ; 10(1): 1-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10565538

RESUMEN

Neurodegenerative diseases may be caused by expansion of triplet repeats in human genes. To identify novel genes with CAG repeats, we screened a human brain cDNA library with an oligonucleotide probe. Four of the isolated cDNAs were sequenced, analyzed for polymorphisms, chromosomal localization, evolutionary conservation and expression. One of the repeats is bi-allelic with 10 triplets (80% of chromosomes) and 7 triplets (20% of chromosomes). In one of the genes two CAG repeats coding for 10 and 17 glutamines are localized in the same reading frame.


Asunto(s)
Encéfalo/fisiología , Enfermedades Neurodegenerativas/genética , Repeticiones de Trinucleótidos/genética , Animales , Southern Blotting , Estudios de Casos y Controles , Gatos , Bovinos , Cromosomas Humanos , Clonación Molecular , Perros , Dosificación de Gen , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Mapeo Restrictivo , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
6.
J Am Dent Assoc ; 100(4): 561-2, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6928897

RESUMEN

A case of an oral fibrolipoma located beneath a mandibular complete denture in a 65-year-old white woman has been presented. The soft, freely movable, yellow encapsulated mass, covered by thin epithelium with a vascular pattern, measured 15 mm in diameter. The fibrolipoma appeared radiographically as a radiolucent area above the left mandibular ridge. The patient's history disclosed no symptoms of pain, bleeding, or discomfort caused by the mass under the denture. A concave area in the mandibular denture corresponding to the location of the tumor indicated that the previous denture was made over the existing tumor. The mass was excised. Histopathologic examination disclosed benign epithelium overlying adipose tissue divided by connective tissue. The diagnosis was benign fibrolipoma. The healing process was uncomplicated. New dentures were made after healing was complete. There has been no evidence of recurrence.


Asunto(s)
Dentadura Completa Inferior , Neoplasias Gingivales/patología , Lipoma/patología , Anciano , Femenino , Fibroma/patología , Humanos
12.
Mediators Inflamm ; 2(6): 403-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-18475554

RESUMEN

Increased plasma histamine levels were associated with significantly lowered diamine and type B monoamine oxidase activities in platelet-rich plasma of atopic eczema (AE) patients. The diamine oxidase has almost normal cofactor levels (pyridoxal phosphate and Cu(2+)) but the cofactor levels for type B monoamine oxidase (flavin adenine dinucleotide and Fe(2+)) are lowered. The biogenic amines putrescine, cadaverine, spermidine, spermine, tyramine and serotonin in the sera, as well as dopamine and epinephrine in EDTA-plasma were found to be normal. It is unlikely, therefore, that these amines are responsible for the decreased activities of monoamine and diamine oxidase in these patients. The most likely causative factors for the inhibition of the diamine oxidase are nicotine, alcohol, food additives and other environmental chemicals, or perhaps a genetic defect of the diamine oxidase.

13.
Acta Derm Venereol ; 71(2): 169-70, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1675531

RESUMEN

Free plasma catecholamines were measured by means of a standardized HPLC method in 50 adult patients with psoriasis and in 18 healthy volunteers. The concentrations of circulating norepinephrine were significantly higher in the psoriasis group (p less than 0.005); by contrast only slight differences were found in the epinephrine and dopamine concentrations. The possible mechanisms leading to these changes are discussed.


Asunto(s)
Norepinefrina/sangre , Psoriasis/sangre , Adolescente , Adulto , Cromatografía Líquida de Alta Presión , Dopamina/sangre , Epinefrina/sangre , Humanos , Persona de Mediana Edad
14.
Acta Derm Venereol ; 72(4): 253-5, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1357877

RESUMEN

Purine nucleotide concentrations in skin- and blood-cells of psoriatic patients are abnormal: The increase in the steady state level of cGMP and the decrease in the cAMP concentrations are associated with an enhanced rate of cellular proliferation. Concomitantly we found in the present study decreased ADP and ATP concentrations in blood cells (p less than 0.0001). The change in nucleotide concentrations suggests a defective purine nucleotide synthesis pathway. Stimulation of the Krebs cycle with fumaric acid raises ATP (p less than 0.0001) and most probably cAMP levels and at the same time slows down the purine nucleotide synthesis through end-product inhibition. Both effects can inhibit DNA and protein synthesis activity, which results in inhibition of cellular proliferation. Fumaric acid seems therefore a useful treatment for psoriatic lesions if liver and kidney functions (purine nucleotide and urea cycle) are controlled during treatment.


Asunto(s)
Psoriasis/sangre , Nucleótidos de Purina/biosíntesis , Adenosina Difosfato/sangre , Adenosina Monofosfato/sangre , Adenosina Trifosfato/sangre , Adulto , División Celular , Fumaratos/uso terapéutico , Humanos , Persona de Mediana Edad , Nucleótidos de Purina/sangre
15.
Allergy ; 43(8): 614-6, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3207184

RESUMEN

Free plasma catecholamines were measured by means of a standardized HPLC method in 41 adult patients with severe atopic eczema and in 18 healthy volunteers. The circulating norepinephrine levels were significantly higher in the atopic group (P less than 0.005), by contrast only slight differences were found in the epinephrine and dopamine concentrations. The possible mechanisms leading to these changes at concomitant normal DBH activities are discussed.


Asunto(s)
Catecolaminas/sangre , Dermatitis Atópica/sangre , Dopamina beta-Hidroxilasa/sangre , Adulto , Cromatografía Líquida de Alta Presión , Humanos
16.
Allergy ; 43(4): 318-9, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3133954

RESUMEN

Increased plasma histamine levels were associated with significantly lowered diamine and type B monoamine oxidase activities in platelet rich plasma of atopic eczema patients.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/metabolismo , Dermatitis Atópica/enzimología , Monoaminooxidasa/metabolismo , Adolescente , Adulto , Amina Oxidasa (conteniendo Cobre)/sangre , Plaquetas/enzimología , Humanos , Monoaminooxidasa/sangre
17.
Z Hautkr ; 64(12): 1121-3, 1989 Dec 15.
Artículo en Alemán | MEDLINE | ID: mdl-2517372

RESUMEN

Increased plasma histamine levels were associated with significantly lowered diamine and type B monoamine oxidase activities in platelet rich plasma of atopic eczema (AE) patients. The diamine oxidase has almost normal cofactor levels (pyridoxal phosphate and Cu2+) but the cofactor levels for type B monoamine oxidase (flavin adenine dinucleotide and Fe2+) are lowered.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/sangre , Dermatitis Atópica/enzimología , Histamina/sangre , Isoenzimas/sangre , Monoaminooxidasa/sangre , Adolescente , Adulto , Cobre/sangre , Femenino , Flavina-Adenina Dinucleótido/sangre , Humanos , Hierro/sangre , Masculino , Fosfato de Piridoxal/sangre
18.
Acta Derm Venereol ; 69(3): 264-5, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2566240

RESUMEN

Monoamine- and diamine oxidase activities were measured by a sensitive photometric assay in 25 psoriasis vulgaris patients. Results were compared with plasma histamine values determined fluorimetrically. Increased plasma histamine levels were associated with significantly lowered diamine--and type B monoamine oxidase activities in platelet-rich plasma of the psoriasis patients. Our data suggest that cofactor levels and/or inhibiting factors are responsible for the observed monoamine- and diamine oxidase activities.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/sangre , Monoaminooxidasa/sangre , Psoriasis/enzimología , Adolescente , Adulto , Histamina/sangre , Humanos
19.
Z Hautkr ; 64(11): 1036-7, 1989 Nov 15.
Artículo en Alemán | MEDLINE | ID: mdl-2609712

RESUMEN

By means of a standardized HPLC method, we determined free plasma catecholamines both in 41 adult patients with severe atopic dermatitis and in 18 healthy volunteers. The levels of circulating noradrenaline were significantly higher in the atopic group (p less than 0.005), whereas the concentrations of adrenaline and dopamine, in contrast, were only slightly elevated. We discuss the possible mechanisms leading to these changes in spite of normal activities of DBH.


Asunto(s)
Dermatitis Atópica/enzimología , Norepinefrina/sangre , Adolescente , Adulto , Nivel de Alerta/fisiología , Cromatografía Líquida de Alta Presión , Dopamina/sangre , Dopamina beta-Hidroxilasa/sangre , Epinefrina/sangre , Humanos , Persona de Mediana Edad
20.
Allergy ; 44(4): 298-300, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2500039

RESUMEN

We have recently shown that increased plasma histamine levels were associated with significantly lowered diamine and type B monoamine oxidase activities in platelet rich plasma of atopic eczema patients. We now report almost normal cofactor (pyridoxal phosphate and Cu2+) levels for diamine oxidase but lowered cofactor (flavin adenine dinucleotide and Fe2+) levels for type B monoamine oxidase.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/sangre , Dermatitis Atópica/enzimología , Monoaminooxidasa/sangre , Adolescente , Adulto , Amina Oxidasa (conteniendo Cobre)/antagonistas & inhibidores , Histamina/sangre , Humanos
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