Search PubMed⌕ Search

Biomedical subjects

M Rasche

Publications and source records attributed to M Rasche.

5 recordsLinked to original sources

Reply to Satomura.

Explore the source record for details and available documents.

Glomerulonephritis, IGA↗

Characterization of the metal centers of the Ni/Fe-S component of the carbon-monoxide dehydrogenase enzyme complex from Methanosarcina thermophila.

Methanosarcina thermophila contains a multienzyme complex called the carbon-monoxide dehydrogenase complex, which has been resolved into a nickel/iron-sulfur and a corrinoid/iron-sulfur component. This complex plays a central role in acetoclastic methanogenesis. The Ni/Fe-S component catalyzes CO oxidation and has been proposed to be involved in cleavage of acetyl-CoA into its methyl, carbonyl, and CoA moieties. In the work reported here, three metal centers in the Ni/Fe-S component were characterized by electron paramagnetic resonance (EPR) spectroscopy and spectroelectrochemistry and pre-steady state kinetics. Center A contains nickel and iron and forms an EPR active adduct with CO, which is called the NiFeC species. The EPR spectrum of the NiFeC species has g values of 2.059, 2.051, and 2.029 and is observable at temperatures as high as 150 K. This signal had previously been observed only in the carbon-monoxide dehydrogenase complex of M. thermophila and the acetyl-CoA synthase from acetate-producing bacteria. Incubation of the CO-reduced Ni/Fe-S component with acetyl-CoA resulted in an increase in intensity of the NiFeC signal, which supports a role for the component in the cleavage of acetyl-CoA. Generation of the NiFeC EPR signal occurs with a rate constant of 0.4 s-1, a result that demonstrates the kinetic competence of this species in the acetyl-CoA cleavage reaction but rules it out as the site of oxidation of CO to CO2. Center B is likely to be a [4Fe-4S]2+/1+ center with g values of 2.04, 1.93, and 1.89 (gav = 1.95) and a standard reduction potential (E'0) of -444 mV. At potentials less than -500 mV, another EPR signal develops that appears to originate from another state of Center B. Center C is a fast relaxing center with g values of 2.02, 1.88, and 1.71 (gav = 1.87) and an E'0 of -154 mV.

Aldehyde Oxidoreductases↗

[Resorption of prostaglandin E2 following various methods of local administration for ripening of the cervix and end the induction of labor].

PGEM concentration was determined radioimmunologically in a non-pregnant woman in whom PGE2 was infused intravenously at increasing dosage and in women in whom labour was induced by various methods for local application of PGE2. There was excellent correlation between the amount of PGE2 infused intravenously and the levels of PGEM determined in the peripheral plasma. The following methods of local application of PGE2 were included in the study: 0.4 mg PGE2 gel placed retroamnially by means of a balloon catheter; 0.4 and 0.5 mg PGE2 gel applied endocervically; 1.5 mg PGE2 given pericervically through a portio adapter and 3 mg PGE2 placed intravaginally in form of a single vaginal tablet; also included was a control group where only vaginal examination was performed. Blood was withdrawn before, and then 30 minutes, 1, 2 and 3 hours after PGE2 administration. Mean levels of PGEM in the maternal peripheral plasma showed no change within or between the various groups, with the exception of one patient in the portio adapter group where hyperstimulation occurred. After removal of the adapter PGEM levels dropped to baseline values. It is concluded from the present study that local application of doses currently used to soften the cervix and/or induce labour at term does not give rise to PGEM concentrations in the maternal blood of the same magnitude as achieved by intravenous PGE2 administration.

Abortion, Induced↗

Plasma concentration of 13,14-dihydro-15-keto-PGE2 (PGEM) after various ways of cervix ripening with PGE2.

PGEM concentration was determined radioimmunologically in a non-pregnant woman, in whom PGE2 was infused intravenously at increasing rates and in women, in whom labor was induced by various methods for local application of PGE2. There was excellent correlation between the amount of PGE2 infused intravenously and the levels of PGEM determined in the peripheral plasma. The following methods of local application of PGE2 were included in the study: 0.4 mg PGE2 gel placed retroamnially by means of a balloon catheter, 0.4 and 0.5 mg PGE2 applied endocervically and 3 mg PGE2 placed intravaginally in form of a single vaginal tablet; also included was a control-group, where only vaginal examination was performed. Bloods were drawn before, 30 minutes, 1, 2 and 3 hours after PGE2 administration. Mean levels of PGEM in the maternal peripheral plasma did not change neither within nor between the various groups. It is concluded from the present study, that local application of doses currently used to soften the cervix and/or induce labor at term do not lead to the same PGEM-concentration in the maternal blood as after intravenous infusion of PGE2 in doses normally used to induce labor.

Cervix Uteri↗

[Premature membrane rupture: effect of intracervical PGE2 gel administration on plasma oxytocin, PGFM and PGEM levels in mother and child].

Premature rupture (= PR) of the amnion is a serious complication even for the mature child if it occurs earlier than 24 hours before birth. To keep the interval as short as possible, the authors induce labour from week 35/0 in case of PR, provided the Bishop score is greater than 7. If the bishop score is lower, they conduct intracervical priming of the cervix with 0.4 mg PGE2 gel before induction of labour. This has proved clinically superior to intravenous procedures. In the study presented here, the authors attempted to find out whether intracervical administration of PGE2 gel would result in changes in the maternal and foetal plasma concentrations of oxytocin, PGFM, or PGEM when comparing conditions in case of ruptured amnion with those if the amnion remained intact. If the amnion is intact and the cervix immature (less than 2 cm), intracervical administration of 0.4 mg PGE2 gel produces a significant OT increase within 30 minutes. From a cervical width of 2 cm onwards, the OT levels are already primarily enhanced and will hardly change even after PGE2 gel administration. Similar conditions obtain in PR. PGFM plasma levels will rise only slightly within an hour after intracervical PGE2 gel administration, independent of whether there has been a rupture or not, or whether the cervix is dilated less than 2 cm or 2 cm and more.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗