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H Baumann

Publications and source records attributed to H Baumann.

At least 217 records · Page 12Linked to original sources
PubMed1986

[Altitude exposure and staying at high altitude in pregnancy: effects on the mother and fetus].

In this paper we review some effects of acute and short-term exposure to altitude on maternal and fetal cardio-pulmonary function. These effects may be seen during commercial aircraft flight or mountain ascent in cablecars. In addition cardio-pulmonary changes during maternal exercise at altitude are discussed. Altitudes up to 2 500 m are well tolerated by mother and fetus in uncomplicated pregnancies. Slight maternal exercise does not provoke fetal heart rate changes. However, in pregnancies at risk, for example because of maternal smoking, precaution with exposure to altitude is justified. Particularly at risk may be stewardesses if they continue their strenuous work while pregnant. Living at high altitude (more than 2 500 m) the lower oxygen partial pressure has some well known negative effects on mother and fetus. The importance of the various mechanisms of acclimatisation and adaptation to hypoxaemia, and other factors influencing reproduction when living at high altitude are reviewed and discussed.

Acclimatization↗
PubMed1985

An evolutionary switch in tissue-specific gene expression. Abundant expression of alpha 1-antitrypsin in the kidney of a wild mouse species.

alpha 1-Antitrypsin (AT), one of the major proteinase inhibitors in mammalian serum, is generally considered to be synthesized exclusively in the liver. We have found that a wild-derived Mus species, Mus caroli, expresses AT mRNA in kidney at levels approaching that in liver; no other mouse, inbred or wild-derived, exhibits this striking property. Liver and kidney mRNAs from M. caroli encode very similar AT polypeptides that are distinct from that encoded by Mus musculus liver mRNA. In vivo, liver AT is secreted into the bloodstream, while kidney AT, which is processed differently from the liver protein, is excreted into the urine. Analysis of RNA from a hybrid between M. musculus and M. caroli indicates that a cis-acting genetic element may be responsible for the difference in AT expression. Restriction enzyme digestion patterns of AT genomic sequences in M. caroli DNA are considerably different from those in M. musculus; in addition, these sequences are undermethylated in liver DNA from M. musculus and in liver and kidney DNA from M. caroli, reflecting the respective patterns of expression. Further studies of the altered tissue specificity of AT expression that is apparent in these two related species should lead to new insights into the nature and evolution of genetic determinants of tissue-specific phenotypes.

Animals↗
PubMed1985

Genetics and evolution of the acute phase proteins in mice.

In mammals, a number of liver-derived plasma proteins, termed acute phase reactants, are induced during an inflammation response. We have studied genetic variation in the structure and expression of several of these proteins in a variety of inbred and wild-derived mice. In a genetic cross, electrophoretic polymorphisms for the two alpha 1-acid glycoproteins, AGP-1 and AGP-2, co-segregated in 58 backcross progeny, indicating that either a single gene or two tightly-linked genes on chromosome 4 encode the AGPs. In the same backcross, segregation of variation in haptoglobin structure showed that the gene encoding this acute phase reactant is on chromosome 8. Structural variation in serum amyloid A correlated with restriction fragment length polymorphisms in the Saa gene determined by Taylor and Rowe (1984). Analysis of a number of highly diverged species of mice indicated that AGP expression has undergone considerable modification during evolution of the Mus genus; this is associated with alterations in Agp gene organization, which may include species-specific amplification and/or deletion events.

Animals↗
PubMed1985

[Reaction of mother and fetus to physical stress at high altitude].

The objective of the study reported here was to investigate the reactions of mother and fetus to high-altitude hypoxia combined with physical exercise. The climb was passive, by means of scheduled journeys of the Grap Sogn Gion AG aerial cableway in Laax (Switzerland). The valley station is at an altitude of 1100 m, the mountain station at 2200 m. The mother exercised on a bicycle ergometer set to 25 watts for 3 minutes. The following were measured continuously and noninvasively: heart rate, respiratory rate, systolic and diastolic blood pressure, Po2 and Co2, uterus activity, and fetal heart rate. Twelve pregnant women with an average gestational age of 36 weeks (30th-39th week) took part in the study. Ten of the women were primiparae and two multiparae. During the trip up the mountain the barometric pressure dropped on average from 668 to 583 mmHg. This resulted in a maximum difference in Po2 between the valley and mountain stations of 18 mmHg. There were no systematic changes in Po2. Respiratory rate, heart rate, systolic and diastolic blood pressure remained unchanged during the trip up the mountain. The physical exercise at the mountain station led to an increase in respiratory rate from 12 to 20 min-1, while heart rate rose from 103 to 128 min-1, systolic blood pressure from 117 to 144 mmHg, and diastolic blood pressure from 70 to 90 mmHg. Six of the 12 women had regular contractions even during the trip up the mountain; these either remained unchanged or became less frequent in the course of the study. The mean fetal heart rate only changed slightly.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Clinical experience with nimodipine in the prophylaxis of neurological deficits after subarachnoid hemorrhage.

The efficacy and tolerability of the dihydropyridine calcium antagonist nimodipine (BAY e 9736) in the prophylaxis of ischemic neurological deficits after subarachnoid hemorrhage were investigated in 171 patients in an open, prospective, multicenter study. 68 of the patients had to be excluded from the efficacy assessment as they had failed to satisfy important inclusion criteria. The efficacy assessment was based on 104 patients of Hunt and Hess grades I-III. In 86 patients the ruptured aneurysm was clipped before or during the nimodipine therapy, while 18 patients did not undergo surgery owing to failure to detect an aneurysm, continuous deterioration of the clinical condition, or for other reasons. At the end of the nimodipine treatment 74 of the patients (71%) were completely free from symptoms or had only very slight neurological deficits. There were 10 patients (10%) with moderate and 10 with a severe disablement, 4 patients were apallic, and 6 (6%) died during the nimodipine treatment. In 4 patients (3.8%) cerebral vasospasm was the sole cause of severe neurological deficits or death, while in a further 3 patients (2.7%) vasospasm and other serious complications were responsible for poor outcome. 22 of the 171 patients (12.9%) died during or shortly after nimodipine therapy. Rebleeding occurred during nimodipine therapy in 7 of the 143 preoperatively treated cases (4.9%).

Adult↗
PubMed1985

[Sialochemical and morphology studies of the submandibular gland of the diabetic patient--a contribution to diabetic sialadenosis].

Sixty-four sialochemical and six morphological examinations were carried out on diabetics with swollen glandula submaxillaris. The significant decrease of the sodium content, the significant increase of potassium content as well as the significantly decreased amylase content of submaxillary saliva speak for diabetogenous sialadenosis. The microscopical and ultramicroscopical findings in needle biopsies confirm the morphological pattern of sialadenosis in the diabetic submaxillary gland.

Amylases↗
PubMed1984

Size-exclusion high-performance liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins: a comparison.

When size-exclusion HPLC (SE-HPLC) is applied for the separation of hydrophilic and hydrophobic proteins, numerous problems can be encountered, which may present considerable difficulties. A major source of such complications is interaction between column packing and sample, especially on the so-called "Diol" and "Polyol" columns. In many cases interaction can be reduced only by adding detergents. Calibration proteins and hydrophobic membrane proteins of liver are separated by SE-HPLC. The influence of detergents on association and dissociation of protein subunits and protein configuration is shown. These factors can affect the elution volume during chromatography. Furthermore it is shown that a direct comparison can be drawn between the protein separation by SE-HPLC on the one hand and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis on the other hand. As an example the separation of the delta-subunit of the acetylcholine receptor was shown under reducing and nonreducing conditions.

Animals↗
PubMed1984

Human keratinocytes and monocytes release factors which regulate the synthesis of major acute phase plasma proteins in hepatic cells from man, rat, and mouse.

Human keratinocytes and activated monocytes produces factors which can stimulate the proliferation of thymocytes. The same activity has also been implicated in regulating the expression of plasma proteins in liver cells during the acute phase reaction. To assess whether factors produced by such cells can directly influence liver cells to change the production of acute phase plasma proteins, we studied in tissue culture the response pattern of hepatic cells from three species: human hepatoma cells ( HepG2 cells), and primary cultures of rat and mouse hepatocytes. Conditioned media from the squamous carcinoma COLO-16 cells, normal epidermal cells, and activated peripheral monocytes were able to stimulate the synthesis of specific acute phase plasma proteins: alpha 1-antichymotrypsin in HepG -2 cells, alpha 1-antichymotrypsin, alpha 1-acid glycoprotein, alpha 1-acute phase protein, and alpha 2-macroglobulin in rat hepatocytes, and alpha 1-acid glycoprotein, haptoglobin, and hemopexin in mouse hepatocytes. Only in rat cells, dexamethasone was found to have further enhancing effect. The increased production of plasma proteins could be explained by an elevated level of functional mRNA. Comparing thymocyte-stimulating activities with the effects on plasma protein production, we found some difference both between the conditioned media of epidermal cells and monocytes, and between the responses of the three hepatic cell systems. Furthermore, gel chromatography of conditioned media resulted in partial separation of activities regulating liver cells and thymocytes. Since there is no strict correlation between thymocyte- and hepatocyte-stimulating activities, the presence of different sets of specific factors is assumed.

Acute-Phase Proteins↗
PubMed1984

[Incidence of HBsAG in symptom-free pregnant women. Results of screening at the University of Zurich Gynecology Clinic].

Passive and active immunization prevent materno-fetal and postnatal hepatitis B-virus infection. Precondition for interruption of perinatal transmission is knowledge of the mothers' hepatitis B markers before delivery. In switzerland the prevalence of chronic asymptomatic pregnant HBsAG carriers is not known. From February to December 1983 all pregnant women at the Obstetric Clinic, University Hospital of Zurich were screened for HBsAG. 30 out of 2550 women were HBsAG positive (1.2%); the prevalence among Swiss women is 0.5%, and among immigrants 1.9%. It is suggested that screening for HBsAG be confined to pregnant women who belong to a risk group and to immigrants, and that all children born of HBsAG positive mothers be immunized actively and passively regardless of the presence of HBeAG and/or anti-HBe.

Female↗
PubMed1984

Lead poisoning as a toxogenetic disease.

In two non-related patients suffering from acute lead intoxication a persistent decrease in red cell delta-aminolevulinic acid dehydratase (synonym: porphobilinogen synthase) activity of 30%-60% of controls was noted after treatment and normalisation of lead levels and heme precursors in urine and blood. An inherited enzyme deficiency was suggested and confirmed by a subnormal activity in the mothers of both patients. These four persons are considered as heterozygotes with an increased sensitivity to lead exposure.

Adult↗
PubMed1984

The acute phase response of mouse liver. Genetic analysis of the major acute phase reactants.

We have examined changes in translatable liver mRNAs during the acute phase response in several inbred mouse strains. Induction of mRNAs for the known acute phase reactants serum amyloid A, hemopexin, haptoglobin, and alpha 1-acid glycoprotein was observed. Two alpha 1-acid glycoproteins, termed AGP-1 and AGP-2, differing in size and charge, were found in all mice and appear to derive from distinct yet closely related mRNAs. Polymorphism in the structure of AGP-1 among strains was used to map the structural gene, Agp-1, to chromosome 4 near the b locus. Structural variation for serum amyloid A enabled mapping its structural gene, S alpha alpha, to chromosome 7, near Gpi-1. A wild-derived population of mice, Mus spretus, contains several variations of interest, including structural variations in many acute phase proteins and a putative regulatory variation specific to AGP-1. Further analysis of these genetic variants should provide novel insights into the acute phase response and the factors that mediate it.

Animals↗
PubMed1984

Transfer of plasma membrane proteins between cells using reconstituted membrane vesicles as shuttle vehicles.

Purified membrane glycoproteins from liver or hepatoma tissue culture cells were incorporated in a right-side-out orientation into reconstituted phospholipid vesicles by a detergent dialysis method. The phospholipids were purified from membrane preparations of rat liver. The protein:phospholipid ratio of the reconstituted vesicles was optimized for efficient transfer of vesicle contents to the recipient cells, usually mouse L cells. Fluoresceinated albumin incorporated into the lumen of reconstituted vesicles was used as a marker for transfer after polyethylene glycol-mediated fusion. The redistribution and fate of both the lipids and the transferred membrane proteins were analysed by microscopic and biochemical methods. A hepatocyte-specific binding protein for galactose- or galactosamine-terminated serum glycoproteins and a set of hepatoma cell plasma membrane glycoproteins were successfully transferred to the plasma membrane of mouse fibroblasts by these methods. The biological function of the hepatic binding protein, namely delivery of the galactose-terminated glycoprotein ligand to the lysosome for degradation, was imparted to the mouse fibroblast after transfer. Further, both the polypeptide and the carbohydrate moieties of a set of membrane proteins were degraded at about the same relative rates as they had in the original donor cells, after transfer to the plasma membrane of recipient mouse fibroblasts. These studies show that the technique of inserting membrane constituents into the plasma membrane of another cell can help to elucidate the route and mechanism of membrane protein function and turnover.

Animals↗
PubMed1984

Improved resolution with one-dimensional polyacrylamide gel electrophoresis: myofibrillar proteins from typed single fibers of human muscle.

Standard procedures for one-dimensional discontinuous sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and silver staining were modified to give more effective separation and an improved resolution of human skeletal muscle proteins. In this system, an electrophoresis buffer composed of 100 mM L-isoleucine, 25 mM Tris base, and 0.1% SDS was used. The separating gel consisted of 16% acrylamide with N,N'-methylenebisacrylamide as a crosslinker (1:23), 0.4% SDS, 1.5 M Tris-HCl, pH 8.8. By the present procedure, the slow and the fast forms of myosin light chains (LCs, LCf) and other contractile proteins from human muscle could be better separated. The silver stain is based on a combination of methods previously described. The modified method requires a small fragment of a single fiber to observe as few as 10 ng of myofibrillar muscle proteins. The described simplifications made it possible to assay and compare up to 40 single fibers in the same electrophoretic run. Improved separation of other proteins migrating at basic pH could be achieved by a similar approach.

Electrophoresis, Polyacrylamide Gel↗
PubMed1984

[Late primiparity: what has changed in the last 25 years?].

The case reports of late primiparae greater than 35 years of age were analysed in respect of the change of anamnestic risks, of the course of pregnancy, birth and puerperium, as well as of infant data. The incidence of late primiparae rose in our clinic from A 1.8% (n = 292, infants n = 294), via B 2.6% (n = 210, infants n = 213) to C 3.7% (n = 222, infants n = 225.) Previous history of internistic diseases was rare during all periods. In period C, the anamnestic risk "Status after sterility treatment" attains increasing importance (17%). The incidence of pre-eclamptic toxaemia (toxaemia associated with oedema, proteinuria and hypertension) with blood pressure levels greater than 140/90 mgHg and proteinuria greater than 1 0/00 is 5-7% for all periods. Preeclampsia and eclampsia are rare. During the C period, almost every tenth late primigravida received tocolytics. In 1979, 31% of the late primiparae were subjected to genetic amniocentesis, whereas in 1982 the percentage was 51% of the late primiparae. Spontaneous deliveries decreased from 81% (A) to 50% (C). The rates of Caesarean sections increased from 11% (A) via 21% (B) to 35% (C); hence, they were twice as high during all periods than among the entirety of hospital patients included in this study. The increase in the quota of Caesarean sections is due to the indications "foetal distress ante partum", "breech presentation" and the liberal use of Caesarean section in underweight infants. For example, the category of newborn with a bodyweight below 2500 g, the rate of Caesarean sections increased from 7% (A) to 56% (C).(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1983

Glucose starvation leads in rat hepatoma cells to partially N-glycosylated glycoproteins including alpha 1-acid glycoproteins. Identification by endoglycolytic digestions in polyacrylamide gels.

Within minutes of glucose starvation confluent monolayers of rat hepatoma cells synthesize glycoproteins, including alpha 1-acid glycoprotein, which appear on two-dimensional gels as size heterogeneous spot series. The longer the period of glucose starvation the more the production of the glycoproteins is shifted toward smaller molecular weight forms. To compare these forms with the corresponding glycoproteins synthesized either in a cell-free system or by nonstarved cells, a mapping of the N-glycan was done by endo-beta-N-acetylglucosaminidase digestion within a polyacrylamide gel. Glycoproteins from glucose-starved cells contain a reduced number of N-glycans which belong to both the endo H-sensitive and resistant type. The decrease of N-glycosylation may be correlated with the accumulation of truncated lipid-bound oligosaccharides, for the gel chromatography of the oligosaccharides released from the lipid and protein fractions of glucose-starved cells revealed a drastic reduction in their size. Most of the lipid-linked oligosaccharides synthesized during glucose starvation are resistant to endo H digestion. Under conditions of limiting glycosylation we were able to show by glycopeptide analysis, that in the case of alpha 1-acid glycoprotein, N-glycans are added randomly to the 6 possible N-glycosylation sites. Furthermore, non- or partially N-glycosylated proteins do not acquire additional oligosaccharide units after restoration of glucose although the proteins can undergo secondary modification and, in the case of the secretory proteins, can be exported.

Acetylglucosaminidase↗
PubMed1983

Immunocytochemical localization of chromatin regions UV-microirradiated in S phase or anaphase. Evidence for a territorial organization of chromosomes during cell cycle of cultured Chinese hamster cells.

Chinese hamster cells (M3-1 line) in S phase were laser-UV-microirradiated (lambda, 257 nm) at a small site of the nucleus. Cells were fixed either immediately thereafter or in subsequent stages of the cell cycle, including prophase and metaphase. The microirradiated chromatin was visualized by indirect immunofluorescence microscopy using antibodies specific for UV-irradiated DNA. During the whole post-incubation period (4-15 h) immunofluorescent labelling was restricted to a small part of the nucleus (means, 4.5% of the total nuclear area). In mitotic cells segments of a few chromosomes only were labelled. Following microirradiation of chromosome segments in anaphase, immunofluorescent labelling was observed over a small part of the resulting interphase nucleus. A territorial organization of interphase chromosomes, i.e. interphase chromosomes occupying distinct domains, has previously been demonstrated by our group for the nucleus of Chinese hamster cells in G1. Our present findings provide evidence that this organization pattern is maintained during the entire cell cycle.

Anaphase↗