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We have characterized the respiratory system of the aerobic actinomycete Nonomuraea sp. ATCC 39727. The plasma membrane of the microorganism is shown to contain a protonmotive respiratory chain and H+-ATPase. The respiratory chain is made up of a rotenone-sensitive NADH-quinone oxidoreductase, a four subunits aa3-type cytochrome c oxidase and a bc1 complex. The H+-ATPase is characterized as an F0F1-type on the basis of its sensitivity to specific inhibitors; the enzyme is also inhibited by mM concentrations of Ca2+. The activity of the respiratory chain increases during the exponential growth phase, but is depressed in the stationary phase. The H+-ATPase activity reaches, as the respiratory chain, a maximal activity at the end of the exponential growth phase and then remains constant in the stationary phase.

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Bovine heart cytochrome c oxidase was reconstituted in phospholipid vesicles, and the effect of different non-esterified fatty acids (NEFA) was studied on its proton pump and on the proton permeability of the vesicles. Neither parameter appeared to be affected by concentrations of NEFA known to uncouple oxidative phosphorylation (10 microM). Also the permeability for K+ was not affected by them. The fatty acids caused an increase in the rate of electron transfer in the absence, but not in the presence, of uncoupler and/or valinomycin [diminution of the respiratory-control index (RCI)]. The RCI of 8.7-7.5 was decreased to about 4.5 in the presence of 0.27-10 microM-NEFA. Oleic acid was not effective at the above concentrations. Subunit III-depleted enzyme preparations gave vesicles with an RCI of about 5.5, which was decreased to 4.5 in the presence of NEFA. With both native and subunit III-depleted oxidase the RCI was never decreased to the value of 1 by NEFA, as happens with classical protonophores.

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Polyclonal antibodies have been obtained against a synthetic dodecapeptide identical to the aminoacid sequence 120-131 DSPIKDGVWPPE (inferred from its DNA sequence) of Paracoccus denitrificans cytochrome c oxidase subunit III. The antibodies had a titer higher than 1:10000 when tested against the antigen. These antibodies have been used to produce immunological evidence that, despite the fact that subunit III is not isolated with cytochrome c oxidase, it exists in Paracoccus denitrificans lysates. The antibodies did not show reactivity with bovine heart cytochrome c oxidase either by ELISA or immunoblotting. It was also shown that the antibodies react with a single polypeptide present in Paracoccus denitrificans cell lysates, having an apparent molecular weight close to that of subunit III of bovine heart oxidase.

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Volume oscillations of liver mitochondria resulting from valinomycin induced K+ transport, may be represented by the equation At/Am = C'.exp(-beta t).sin(omega 1t+ psi) where At is the oscillation amplitude at time t; Am, the maximal amplitude; beta, the damping coefficient, omega 1 the oscillation frequency, and C' and psi, constants. The kinetic parameters beta and omega 1 increased as a function of valinomycin concentration. Measurement of beta and omega 1 for mitochondria from normal rats (A); diabetic rats (B), and normal rats fed corn oil or lard-supplemented diets (C and D, respectively), yielded an increase in beta (P less than 0.05) in B and D as compared with A, and a decrease in omega 1 in B and D as compared with A and C, respectively. Analysis of mitochondrial lipids revealed significant diminution of arachidonic acid and other polyenoic fatty acids in diabetic and lard-fed rats, as compared with normal rats and corn oil-fed rats, respectively. The conclusion is drawn that the abnormal oscillatory behaviour of diabetic liver mitochondria is related to the alteration of the membrane fatty acid composition.

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Liver D-3-hydroxybutyrate dehydrogenase (OHBD) is subjected to estrogen modulation. Estrogen action was demonstrated by (a) the lesser activity of liver OHBD in female rats, as compared with their male counterparts; (b) the increase of OHBD activity after ovariectomy of sexually mature rats; (c) the decrease of OHBD activity after treatment of gonadectomized or normal rats with 17 beta-estradiol or with artificial estrogens; (d) the decrease of OHBD activity in female rats during sexual development; (e) the effects of tamoxifen on the enzyme activity. The kinetics of OHBD reaction using liver mitochondria from estrogen-treated rats showed a 50% decrease of Vmax, as compared with the control value, in contrast to the other parameters which did not vary. These results, taken together with the effect of estrogens on liver mitochondrial phospholipids, point to a decreased content of OHBD in liver mitochondria from estrogen-treated rats. In contrast to OHBD, succinate dehydrogenase and cytochrome oxidase activities, mitochondrial protein synthesis and L-malate + L-glutamate oxidation by coupled liver mitochondria either increased or were not affected by estrogens. Kidney and heart OHBD were affected by ovariectomy and estrogens like the liver enzyme, though to a lesser degree.

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22 patients with radiolucid stones and functioning gallbladder were grouped to establish ursodeoxycholic acid efficacy (i.e. gallstones dissolution) and innocuousness for gallbladder lithiasis. Methodological aspects were detailed, the dose determined (8 and 10 mg/k/d.) and the patients evaluated after a six months' treatment. 11 patients received "day-time" doses and the other 11 "overnight" dose. Only 7 subjects turned out to be evaluated for the study of biliary lipids, to the other 15 the development of their gallstones was followed up. Successful gallstone dissolution was achieved in 8 patients (53,3%), 2 reduced size and number. 5 out of these 8 patients received "day-time" doses and the other 3 "overnight" doses. From an attendance point of view, we do not consider biliary lipids study (bile cholesterol saturation rate) to be necessary.

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Con la finalidad de establecer la eficacia (disolucion de calculo/s) e inocuidad del acido ursodesoxicolico en el tratamiento de la litiasis vesicular, se agruparon 22 pacientes con calculos radiolucidos y vesicula biliar funcionante. Se detallan aspectos metodologicos fijandose la dosis entre 8 y 10 mg./k/d evaluandose a los pacientes despues del sexto mes de tratamiento. 11 pacientes recibieron dosis "diurnas" y los 11 restantes dosis "nocturnas". 7 pacientes solo resultaron evaluables para el estudio de los lipidos biliares. De los 15 restantes a todos se les siguio la evolucion de sus calculos,8 (53,3%) disolvieron los mismos y en 2 se observo reduccion de numero y tamano. De esos 8 pacientes,5 recibieron dosis "nocturnas" y 3 "diurnas". Desde el punto de vista asistencial no creemos necesario el estudio de los lipidos biliares (indice de saturacion del colesterol biliar). Concluimos que el acido ursodesoxicolico resulta un farmaco util para tratar determinados casos de calculos vesiculares, sin haber observado reacciones adversas

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22 patients with radiolucid stones and functioning gallbladder were grouped to establish ursodeoxycholic acid efficacy (i.e. gallstones dissolution) and innocuousness for gallbladder lithiasis. Methodological aspects were detailed, the dose determined (8 and 10 mg/k/d.) and the patients evaluated after a six months treatment. 11 patients received [quot ]day-time[quot ] doses and the other 11 [quot ]overnight[quot ] dose. Only 7 subjects turned out to be evaluated for the study of biliary lipids, to the other 15 the development of their gallstones was followed up. Successful gallstone dissolution was achieved in 8 patients (53,3

), 2 reduced size and number. 5 out of these 8 patients received [quot ]day-time[quot ] doses and the other 3 [quot ]overnight[quot ] doses. From an attendance point of view, we do not consider biliary lipids study (bile cholesterol saturation rate) to be necessary.

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Con la finalidad de establecer la eficacia (disolucion de calculo/s) e inocuidad del acido ursodesoxicolico en el tratamiento de la litiasis vesicular, se agruparon 22 pacientes con calculos radiolucidos y vesicula biliar funcionante. Se detallan aspectos metodologicos fijandose la dosis entre 8 y 10 mg./k/d evaluandose a los pacientes despues del sexto mes de tratamiento. 11 pacientes recibieron dosis "diurnas" y los 11 restantes dosis "nocturnas". 7 pacientes solo resultaron evaluables para el estudio de los lipidos biliares. De los 15 restantes a todos se les siguio la evolucion de sus calculos,8 (53,3%) disolvieron los mismos y en 2 se observo reduccion de numero y tamano. De esos 8 pacientes,5 recibieron dosis "nocturnas" y 3 "diurnas". Desde el punto de vista asistencial no creemos necesario el estudio de los lipidos biliares (indice de saturacion del colesterol biliar). Concluimos que el acido ursodesoxicolico resulta un farmaco util para tratar determinados casos de calculos vesiculares, sin haber observado reacciones adversas

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To investigate ursodeoxycholic acid (Urso) action on liver histology, 30 male hamsters were allocated to 2 groups of 15 animals each; one group was treated with Urso, and the other one acted as control. Thirty days later, a light and electron microscopy study of the liver of all the animals was performed. All the group receiving Urso acid revealed minimal changes consisting in hepatocytic nuclear vacuolization around the centrelobulilla area; the vacuoles were homogeneous and contained a pale basofilic material. Neither inflammatory lesions nor hepatic cell necrosis was observed. Electron microscopy showed folding of the nuclear membrane corresponding to vacuoles observed under light microscopy. Further studies must be carried out to make clear the meaning of our findings and to confirm or otherwise rectify Urso inocuity on the liver of hamsters.

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Para investigar la accion del acido ursodesoxicolico (Urso) sobre la histologia hepatica, 30 hamsters machos fueron agrupados en 2 lotes de 15 cada uno administrandosele a un grupo 39 mg./k/dia de Urso, sirviendo el otro lote como control. Despues de 30 dias se realizo estudio con microscopia de luz y electronica de todos los higados. En el grupo que recibio Urso se comprobo en un 100 x 100 de ellos cambios minimos consistentes en vacuolizacion nuclear de los hepatocitos del sector centrolobulillar; las vacuolas eran homogeneas y contenian un material debilmente basofilo. No se observaron lesiones inflamatorias ni necrosis hepatocelular. La microscopia electronica determino la presencia de invaginaciones de la membrana nuclear, correspondiente a las vacuolas observables con el microscopio de luz. Futuros estudios deberan realizarse para aclarar el verdadero significado de nuestros hallazgos y ratificar o no la inocuidad del Urso sobre el higado del hamster

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To investigate ursodeoxycholic acid (Urso) action on liver histology, 30 male hamsters were allocated to 2 groups of 15 animals each; one group was treated with Urso, and the other one acted as control. Thirty days later, a light and electron microscopy study of the liver of all the animals was performed. All the group receiving Urso acid revealed minimal changes consisting in hepatocytic nuclear vacuolization around the centrelobulilla area; the vacuoles were homogeneous and contained a pale basofilic material. Neither inflammatory lesions nor hepatic cell necrosis was observed. Electron microscopy showed folding of the nuclear membrane corresponding to vacuoles observed under light microscopy. Further studies must be carried out to make clear the meaning of our findings and to confirm or otherwise rectify Urso inocuity on the liver of hamsters.

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Para investigar la accion del acido ursodesoxicolico (Urso) sobre la histologia hepatica, 30 hamsters machos fueron agrupados en 2 lotes de 15 cada uno administrandosele a un grupo 39 mg./k/dia de Urso, sirviendo el otro lote como control. Despues de 30 dias se realizo estudio con microscopia de luz y electronica de todos los higados. En el grupo que recibio Urso se comprobo en un 100 x 100 de ellos cambios minimos consistentes en vacuolizacion nuclear de los hepatocitos del sector centrolobulillar; las vacuolas eran homogeneas y contenian un material debilmente basofilo. No se observaron lesiones inflamatorias ni necrosis hepatocelular. La microscopia electronica determino la presencia de invaginaciones de la membrana nuclear, correspondiente a las vacuolas observables con el microscopio de luz. Futuros estudios deberan realizarse para aclarar el verdadero significado de nuestros hallazgos y ratificar o no la inocuidad del Urso sobre el higado del hamster

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