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E Hartmann

Publications and source records attributed to E Hartmann.

At least 127 records · Page 7Linked to original sources
PubMed1990

Segregation of the signal sequence receptor protein in the rough endoplasmic reticulum membrane.

The signal sequence receptor (SSR), an integral membrane glycoprotein of 34 kDa, has previously been shown to be a component of the molecular environment which nascent polypeptide chains meet in passage through the endoplasmic reticulum (ER) membrane. We have used antibodies directed against the SSR and both immunocytochemistry and cell fractionation to determine its distribution in rat liver cells. SSR was found largely restricted to the rough ER. Only small amounts of the protein were detected in smooth ER. These results provide further evidence for a functional differentiation of rough and smooth ER and for a role of SSR in protein translocation across the ER membrane.

Animals↗
PubMed1990

[Effect of removal of calculus on periodontium by hand- and roto-pro-instruments].

It was the aim of this clinically longitudinal study to find out the consequence of the removal of calculus with hand- and roto-pro-instruments of the periodontium in 50 patients suffering from periodontal diseases. There are no clinically provable differences between the two methods of the removal of calculus. Both methods cause a statistically significant effect on the inflammatory factors of the periodontium.

Dental Calculus↗
PubMed1989

Photocrosslinking demonstrates proximity of a 34 kDa membrane protein to different portions of preprolactin during translocation through the endoplasmic reticulum.

Photocrosslinking has been used to identify integral proteins of the endoplasmic reticulum membrane that are in proximity to nascent preprolactin during in vitro translocation. A photoreactive lysyl derivative was introduced into truncated preprolactin chains comprising 86 or 115 amino acids. Both with the 86mer, containing the reactive group in the signal sequence, and with the 115mer, containing the probe exclusively in the mature portion of the chain, photocrosslinking occurred to an approximately 35 kDa transmembrane glycoprotein, the signal sequence receptor (SSR). SSR is identical with a previously isolated abundant and ubiquitous 34 kDa membrane protein that appears to be essential for protein translocation.

Animals↗
PubMed1989

A membrane component of the endoplasmic reticulum that may be essential for protein translocation.

We have purified a glycosylated, membrane-spanning protein of relative molecular mass approximately 34,000 (Mr approximately 34 K) from canine microsomes that appears to be essential for protein translocation across the endoplasmic reticulum (ER) as shown by the inhibitory action of antibodies directed against it and of monovalent Fab-fragments produced from them. The ER membrane contains at least as many molecules of the 34 K membrane protein as bound ribosomes. The protein can be detected immunologically in tissues of various organisms, indicating an universal function.

Animals↗
PubMed1989

Predicting the orientation of eukaryotic membrane-spanning proteins.

We have developed a rule to predict the orientation of the first internal signal-anchor sequence in eukaryotic transmembrane proteins synthesized on the rough endoplasmic reticulum. The difference in the charges of the 15 residues flanking the first internal signal-anchor determines its orientation, with the more positive portion facing the cytosol. In proteins that span the membrane more than once, the orientation of all subsequent transmembrane segments would be determined by that of the most N-terminal one.

Animals↗
PubMed1989

Diacylglycerol Levels Unchanged during Auxin-Stimulated Growth of Excised Hypocotyl Segments of Soybean.

Diacylglycerol contents of excised soybean (Glycine max L.) hypocotyl segments, incubated for 4 hours in the presence or absence of a growth promoting concentration of 2,4-dichlorophenoxyacetic acid (2,4-D) were monitored by three different methods as a sensitive measure of the action in vivo of C-type phospholipases. By all three methods, steady state levels of diacylglycerols representing about 3% of the total lipids or about 7% of the neutral lipids, depending on method of assay, declined 18% over 4 hours of incubation as determined by extraction of total lipids and analysis by thin layer chromatography and densitometry. The average decline with 2,4-D-treated segments was less but the difference from controls was not significant. In those experiments where a small effect of 2,4-D was noted, the fraction showing an elevated diacylglycerol level in response to 2,4-D, after separation into membrane and supernatant fractions, was the supernatant and not the membranes. Results were confirmed from analyses of total fatty acids in each of the major lipid fractions and from diacylglycerol assays by conversion into phosphatidic acid upon incubation with [gamma-(32)P]ATP and purified diacylglycerol phosphokinase from Escherichia coli. In the presence of 2,4-D, the diacylglycerol content of the membranes was unchanged compared to membranes from control segments. As with the densitometric method, the small 2,4-D induced increase in diacylglycerols, when observed, was insignificant and in the supernatant. The only membrane-associated lipid fraction consistently showing a response to 2,4-D was the fraction containing sterols esterified with fatty acids. Either total microsomes or purified plasma membranes when incubated for 10 to 20 minutes with 1 micromolar 2,4-D showed no accelerated formation of diacylglycerols compared to membranes not incubated. The results do not support operation during auxin growth of the animal paradigm where diacylglycerol activation of C-type protein kinases occurs in response to activated phospholipase C breakdown of phosphoinositides.

Journal Article↗
PubMed1989

The effect of social influence on cognitive development and school performance.

Three months before school entrance a sample of 29 children and their mothers was tested for degree of decentred child educability and degree of decentred maternal teaching. Mother and child were tested in two different situations, thus preventing interdependency between the measures of mother and child. Four months after school entrance, teacher judgements of school performance were obtained. A strong correspondence between degree of decentred child educability and degree of decentred maternal teaching was demonstrated. Degree of decentred maternal teaching and degree of decentred child educability were found to be good predictors of school performance, accounting for respectively 45 and 33% of the variance in school performance. In contrast a test of school readiness only accounted for 2% of the variance. A test of intelligence given after the teacher judgement accounted for 31% of the variance. The fact that the mother seems to be a better predictor of her child's school performance than the child himself, supports the assumption that parents, particularly mothers, are important mediators between the child and the outer world.

Achievement↗
PubMed1989

[Experiences in community social psychiatric ambulatory care].

In the first part of the article, the most important principles of action are described that determined the work done so far in the outpatient department of the Sociopsychiatric Clinic Berne. From this work the idea developed that psychiatric long-term patients would best be cared for by a care system divided into sectors and linked first of all to a community mental health centre. First experiences collected in a community health centre project in Berne are described. Details are given in respect of the location and arrangement of the available rooms and space. The central importance of the round table for the work of the medical and nursing staff with the patients, their families and the entire social environment is stressed. The authors try to explain their mode of working and their attitude on the examples of first contact with the patients and the handling of a crisis situation. It is the aim of this sociopsychiatric work to ensure maximum possible autonomy and self-responsibility of the patients.

Adult↗
PubMed1989

Boundaries of dreams, boundaries of dreamers: thin and thick boundaries as a new personality measure.

Previous work by the author and his collaborators on frequent nightmare sufferers demonstrated that these people had striking personality characteristics which could be called "thin boundaries" in a number of different senses. In order to measure thin and thick boundaries, a 145-item questionnaire, the Boundary Questionnaire, has been developed which has now been taken by over 1,000 persons. Preliminary results are presented indicating that, as predicted a priori, several new groups of nightmare sufferers and groups of art students scored usually "thin," whereas a group of naval officers had usually "thick" boundaries. Overall, thinness on the Boundary Questionnaire correlated highly positively (r = .40) with frequency of dream recall and also significantly (r = .16) with length of sleep.

Art↗
PubMed1988

[Spinal lymphosarcoma in a foal].

The present report describes the clinical and pathological findings of a one year old foal presented with paralysis of the hind legs. Macroscopically and histologically, a lymphosarcoma in the vertebral body and the adjacent epidural space of T 16, in the spleen and the mesenterial lymph nodes was observed. The adjacent spinal cord showed focal degenerative changes characterized by dilatation of myelin sheaths, swollen axons and few macrophages.

Animals↗
PubMed1987

Who has nightmares? The personality of the lifelong nightmare sufferer.

Twelve lifelong nightmare sufferers, 12 vivid dreamers who had no nightmares, and 12 persons who had neither nightmares nor vivid dreams were studied in a series of structured interviews, psychological tests, and other tests. The group with nightmares had significantly higher scores on the "psychotic" side of the Minnesota Multiphasic Personality Inventory profile than the other two groups, scored higher on a "boundary deficit" score of the Rorschach test, and had more first- and second-degree relatives with nightmares, psychological problems, and psychiatric hospitalization. There were no significant differences between the groups with vivid and nonvivid dreams. On interview, the frequent nightmare sufferers were a group of sensitive, open persons who had features of the "schizophrenic spectrum disorders," but who also had artistic and creative tendencies and interests, in contrast to the other groups. These results confirm and extend our previous findings in a group of 38 frequent nightmare sufferers.

Adult↗
PubMed1987

[Determining visual acuity].

Ophthalmologists today need to be able to determine visual acuity accurately more and more frequently. The result depends not only on the optotypes but also on the investigation methods used. Possible errors are discussed.

Humans↗
PubMed1987

Phosphatidylinositol specific phospholipase C of plant stems : membrane associated activity concentrated in plasma membranes.

A phosphatidylinositol-specific phospholipase C of plant stems (EC 3.1.4.10) assayed at pH 6.6 and at 30 degrees C cleaved phosphatidylinositol such that more than 85% of the product was inositol-1-phosphate. Other phospholipids were cleaved 5 to 10% or less under these conditions. The phospholipase had both a soluble and a membrane-associated form. The soluble activity accounted for approximately 85 to 90% of the activity and 15% was associated with membranes. The membrane-associated activity was most concentrated in the plasma membranes of hypocotyl segments of both soybean (Glycine max) and bushbean (Phaseolus vulgaris). The plasma membrane location was verified by analysis of highly purified plasma membranes prepared both by aqueous two-phase partitioning and by preparative free-flow electrophoresis and from the quantitation of the activity in all major cell fractions. Internal membranes also contained phospholipase C activity but at specific activity levels of about 0.1 those present in plasma membranes. Golgi apparatus-enriched fractions from which plasma membrane contaminants were removed by two-phase partition contained the activity at specific activity levels 0.2 those of plasma membrane. Both the soluble and the membrane-associated activity was stimulated by calcium but not by calmodulin, either alone or in the presence of calcium.

Journal Article↗
PubMed1987

[Pathology, diagnosis and therapy of liver abscess].

Bacterial hepatic abscesses are a rare but serious disease. They develop either secondary to injuries or ischemia of the liver, infections in the drainage area of the portal vein, systemic sepsis or biliary infections. An abscess secondary to injuries or ischemia of the liver or infections in the drainage area of the portal vein, is usually caused by a mixed flora consisting of gramnegative aerobes and anaerobic bacteria. Hepatic abscesses secondary to systemic sepsis contain Staphylococci or Streptococci, while in abscesses on the basis of biliary infections gramnegative organisms are found. Clinically, one can find signs of systemic sepsis, pain in the right upper quadrant and a tender enlarged liver. Jaundice is absent unless a biliary obstruction is present simultaneously. The diagnosis is confirmed by ultrasonography or computerized tomography. An uncertain diagnosis can be confirmed by aspiration under ultrasonographic or computertomographic guidance. The therapy consists of administration of antibiotics and surgical or percutaneous drainage. Surgical drainage via laparotomy is always mandatory if one suspects a primary infectious focus within the abdomen. The mortality of multiple liver abscesses is 20 per cent, that of single abscesses 10 per cent. Amebic abscesses have been observed in nonendemic regions sporadically after travel or spontaneously. Clinical and radiological manifestations are the same as for bacterial abscesses. They are differentiated from bacterial abscesses by positive serology for amebiasis or aspiration which yields the typical anchovy paste. Most important complications are hepato-bronchial fistulae, empyema and amebic pericarditis. The therapy consists of a nitroimidazole and a luminal amebicide. Except for diagnostic reasons aspiration is only indicated for large abscesses of the left lobe of the liver. Mortality of an uncomplicated amebic liver abscess should be under one per cent.

Amebicides↗