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M Müntener

Publications and source records attributed to M Müntener.

54 records · Page 3Linked to original sources
PubMed1979

Variable pH dependence of the myosin-ATPase in different muscles of the rat.

For the histochemical demosntration of the Myosin-ATPase (EC 3.6.1.3) the pH of both the preincubation and the incubation medium was varied in steps of 1 within a range: 10.2 to 10.5 and 9.3 to 9.9, respectively. The optimum combinations of both pH values, defined as the ones providing most consistent contrast among the three major types of muscle fibers were determined in 9 different muscles of the rat. The spectrum of optimum combinations differs considerably from muscle to muscle. The reduction of the incubation pH by only 0.1 may drastically change the staining pattern. This probably reflects the unspecificity of the histochemical procedure as well as the plasticity of the ATPase systems. To cope with the lability of the myosin-ATPase the optimum pH values of both media should be determined for each muscle separately.

Adenosine Triphosphatases↗
PubMed1977

Development of trophoblast and placenta of the mouse. A reinvestigation with regard to the in vitro culture of mouse trophoblast and placenta.

At 5 days post conceptionem (p.c.) shortly after implantation, giant cell transformation starts at the abembryonic pole of the blastocyst, spreading over the mural trophoblast; 1 day later, the first ectoplacental giant cells appear at the base of the fast growing ectoplacental cone (derived from the polar trophoblast). Giant cell transformation expands over it periphery. Thus, by the 8th day p.c., the conceptus is separated from the maternal tissue by a continuous layer of giant cells, variable in thickness. Giant cells reach their greatest size by 10 days p.c. in the mural tophoblast and by 12 days p.c. in the chorioallantoic placenta. They are probably no longer formed after that stage. Around the 8th day p.c., the allantois reaches contact with the ectoplacental cone, which develops into the chorioallantoic (definitive) placenta. At 9 days p.c., its four zones can already be discriminated: chorionic plate, labyrinth, junctional zone (trophospongium), and zone of giant cells, respectively. Within the next day, the chorioallantoic placental circulation is established. The yolk sac placental circulation is established by the 9th day p.c. The villi of the proximal layer of the yolk sac increase in size and number, and their capillary network becomes more dense until the 12th to 14th day p.c. This provides evidence that the yolk sac placenta exerts its function--to a certain extent--beyond the establishment of the definitive placenta. Around the 14th day p.c., the placental labyrinth reaches its definitive features. Fetal capillaries in the labyrinth, branching from unbilical blood vessels within the septa of connective tissue are surrounded by trophoblast cells. They form a dense vascular network bathing in maternal blood. The structures of the placental zones remain almost the same during further development, the borders becoming sometimes little blurred. Adjacent to the chorionic plate, subchorionic clefts appear at the 14th day p.c. These clefts become confluent to form the intraplacental space, regularly communicating with the yolk sac cavity. At the end of gestation (19th day p.c.) there is a considerable amount of eosinophilic material ('fibrinoid') between the zone of giant cells and the decidua, probably produced by the giant cells.

Animals↗
PubMed1975

[Histogenesis of the immune system of the "nude" mouse. II. Postnatal development of the thymus: a light microscopical study (author's transl)].

UNLABELLED: The thymus of the homozygous nude mouse embryo is laid down normally. From the 13th day post conceptionem (pc) onwards, however, a maldevelopment takes place (Groscurth und Kistler, 1974). As a result, the anterior mediastinum of the newborn nu/nu mouse contains a rudimentary epithelial organ which resembles parts of an embryonic exocrine gland. In this paper, the light microscopical findings of the postnatal development of the thymus in homo- and heterozygous nude mice are reported. MATERIAL AND METHODS: Homo- and heterozygous nude (nu/nu and nu/+) mice with the genetic background BALB/c were kept under specific pathogen-free (spf) conditions. Three nu/nu and three nu/+ female mice were sacrificed at the following developmental stages: newborn animal, 1st, 2nd, 3rd, 6th, 9th as well as 12th week postpartum (pp). The organs were fixed in Bouin's solution and embedded in paraffin wax. Serial sections (5 mu) were stained with hematoxylin and eosin. RESULTS AND DISCUSSION: The bilobed thymus rudiment of the newborn nu/nu mouse consists of branching ducts. From the 2nd week post partum (pp) onwards, their epithelial cells proliferate. At the same time, some of these cells begin to differentiate into serous and mucous cells. In some parts of the rudiment, they also form thyroid-like follicles. The exocrine cells secrete their products into the lumina of the ducts. As there is no connection between the thymus rudiment and either the epidermis or the digestive tract, an accumulation of secretory products takes place, resulting in a dilatation of the whole duct system. Therefore, the thymus rudiment of the 12-week-old nu/nu mouse consists of a number of communicating cysts which are lined by a flattened epithelium. Cysts lined by an epithelium can also be observed within the thymus of the nu/+ mouse. Two types must be distinguished..

Adipose Tissue↗
PubMed1975

[Histogenesis of the immune system of the "nude" mouse. III. Postnatal development of lymph nodes and spleen: a light microscopical study (author's transl)].

UNLABELLED: In neonatally thymectomized mice, the intermediate cortical zones of the lymph nodes as well as the central portions of the spleen follicles (=thymus dependent areas, TDA) are depleted of lymphocytes within a few weeks (Parrott et al., 1966). The TDA's in the lymphatic tissues of mice homozygous for the gene "nude" (nu/nu) contain also a very small number of lymphocytes. Since only a few developmental stages of the lymphatic tissues in nude mice have been studied, an investigation of the postnatal differentiation of their lymph nodes and spleen seemed worthwhile. MATERIALS AND METHODS: The mice (BALB/c) were maintained under specific pathogen-free (spf) conditions. Heterozygous (nu/ plus) females were mated with homozygous (nu/nu) males in order to obtain the homo- and heterozygous offsprings used in this study. Two nu/nu and two nu/ plus female mice were sacrificed at the following postnatal stages: day 1, 7, 14, 21, 35, 42, 49, 63 and 84, respectively. Newborn and 7 day old mice were fixed in toto in Bouin's solution and embedded in paraffin. From the other animals, spleen and mesenteric lymph nodes were removed and processed in an identical manner. Serial sections were cut at 5 mum and stained with hematoxylin and eosin. RESULTS: The mesenteric lymph nodes of the nu/ plus mice studied were indistinguishable from those of other mouse strains. In the nu/nu mouse, outer cortex and medulla of the mesenteric lymph nodes were found to develop as in normal (nu/ plus) animals, while the intermediate and deep cortex underwent characteristic changes...

Animals↗
PubMed1975

[Test methods for surgical hand disinfection (author's transl)].

As exemplified by a test preparation, methods for assessing the effect of hand disinfection on the resident flora are put up for discussion. The test of a method for hand disinfection must make allowance for conditions prevailing in practice. Accordingly, the following steps should be taken into consideration: A. Single use 1. Immediate disinfecting effect 2. Duration of the disinfecting effect B. Repeated use 3. Course of the initial colony count 4. Immediate disinfecting effect 5. Behaviour of colony count after interruption of the disinfecting method applied. For the purpose of comparing the total count, as with all other disinfecting methods, the colony count must be determined by fractional collection methods; to this end, Traub's procedure may be modified, possibly using the plastic bag method described by Gaschen. A careful statistical evaluation with appropriate transformation of the results is indispensable.

Bacteria↗
PubMedDate not supplied

Age-dependent changes of the normal human spine during adulthood.

The impact of aging on the morphology of the osseous spine is still debated. Clinical studies usually record combined aging effects, as well as age-related degenerative changes. The aim of this study was to determine the impact of (degeneration-independent) aging on the morphology of the osseous human spine during adulthood. Various osseous dimensions of human spinal landmarks at all major vertebral levels have been assessed in macroscopically normal Swiss skeletons (N = 71), with historically known sex and age at death, as well as in larger Central European skeletal samples (N = 277) with anthropologically determined individual age and sex. All measurements were correlated with individual age (or age group) by linear regression and analyzed separately for each sex. Only few osseous spinal dimensions, and only in men, correlate significantly with individual age. Generally, the significant dimensions show an increase in size during adulthood. Similar tendencies, but with significant alterations of spinal measurements in women as well, can be found in the larger samples with anthropologically determined sex and age group. Increase of certain spinal dimensions found in this study may be a reflection of an increase in the robustness of individuals with age. Because of the absence of a significant secular alteration of stature within the well-recorded sample, we exclude secular change in body dimensions as a major bias.

Adult↗