Biomedical subjects
Publications and source records attributed to G Lauer.
Relative to nosological classification and therapeutic strategies essential Blepharospasm is discussed controversially in Neurology, Psychiatry, Psychoanalysis, and other related branches. From an integrative point of view the clinical symptomatic is a result of psycho-social factors as well as organic factors. Two own cases are reported. The diagnostic, therapeutic, and prognostic core problems are discussed.
Limited opening of the mouth after surgery of the TMA is often treated by various technical means that are often not appropriate for this function. More specifically, many devices only perform extension to ensure normal opening of the mouth. Until now we have been using the Toronto Medical automated mobilization splint in 21 patients. Passive and continuous extension of the masticatory muscles using this device is a very useful method to achieve normal opening of the mouth in patients suffering from fractures and abscesses. Although this cannot be achieved in patients with tumors and ankylosis, the distance between incisors can still be increased to four times its original value.
This article resumes the most important results of quality of life research on chronic mentally ill patients and argues for the importance of this perspective of evaluation-research. Chronic mentally ill persons experience less quality of life than the general population. Rehabilitation-programs improve the quality of life of chronic mentally ill patients. There is a covariation between better quality of life and length of the interval without being recidivous. Patients of community based programs report a better quality of life than long-term psychiatric inpatients. Finally some open questions and problems concerning quality of life research on the chronically mentally ill are discussed.
We have analysed the expression of p53 at the mRNA level, and extensively at the protein level by immunostaining, Western blotting, and ELISA measurements revealing a p53 increase in 8 out of 14 cell lines established from human pancreatic carcinomas. The mRNA levels closely paralleled the protein levels in most of the cell lines. Overexpression of p53 in tumor cells correlated with mutations in the p53 gene. Immunocytochemistry was also performed with tissue cryosections showing a nuclear p53 staining in 8 out of 12 exocrine, and 2 out of 2 endocrine tumors. In addition, nonmalignant peri-tumoral tissue specimens and cells derived from pancreatic juice of acute pancreatic patients were also positively stained. These findings may suggest functions of p53 in stress situations induced by acute inflammation or tissue regeneration. Genomic mutations in the tumor suppressor gene were associated with point mutations in either codon 12, 13 or 61 in the c-K-RAS oncogene in about two-thirds of cell lines. The frequent activations of a RAS oncogene in combination with mutations of a tumor suppressor gene are likely to contribute to the malignant phenotype of pancreatic adenocarcinomas.
In cultivating gingival epithelium from people up to the age of 66 years it is possible to gain a differentiated mucosal tissue sheet that is more than 100 times the size of the original biopsy surface. The morphological characteristics are a prickle cell layer with polygonal cells and a basal cell layer with flattened cells. Desmosomes, tonofibrils and microplicae at the superficial side of the epithelium are typical features. There is a cell biological differentiation as the distinct binding of lectins and of a cytokeratin antibody proves. The multiplication in surface area, the possibility of using cells of senior patients and the morphological and cell biological differentiation of cultured gingival epithelium are advantages in its application for the autologous bridging of intraoral defects.
We have cloned and sequenced the gene for DNA ligase from Thermus thermophilus. A comparison of this sequence and those of other ligases reveals significant homology only with that of Escherichia coli. The overall amino acid composition of the thermophilic ligase and the pattern of amino acid substitutions between the two proteins are consistent with compositional biases in other thermophilic enzymes. We have engineered the expression of the T. thermophilus gene in Escherichia coli, and we show that E. coli proteins may be substantially removed from the thermostable ligase by a simple heat precipitation step.
83 adults undergoing dental surgical procedures in local anesthesia were monitored continuously with a pulse oximeter for hypoxemia. 30 patients received as premedication either a combination of a neuroleptic drug and an opiate or a benzodiazepine. There was a drop in the oxygen saturation in 80% of the patients with premedication but only in 66% of the patients without. There were statistical highly significant more periods of hypoxemia in patients with premedication compared to the others. (1548 periods versus 659 periods p less than 0.001). The kind of premedication/sedation does not influence the number of hypoxic episodes. We conclude that especially patients with premedication should only be treated by surgeons with sufficient clinical experience in coping with emergency situations.
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Clinical observations and psychopathological reports on patients with endogenous depression suggested a high frequency of alexithymic characteristics in these patients. 21 inpatients with unipolar endogenous depression and 21 inpatients with neurotic-reactive depression, classified according to ICD-9 and DSM-III criteria, were assessed with the content analysis method of Gottschalk-Gleser and the Beth Israel Alexithymia Questionnaire (BIAQ) as well as other questionnaires at two points of time. The gorup with unipolar endogenous depression showed significantly less separation anxiety, diffuse anxiety, total anxiety, hostility directed inward, total hostility and depressivity at both points of time. The endogenous depression group showed significantly higher scores in the BIAQ than the group with neurotic depression. The specifity of alexithymia in psychosomatic patients, its high frequency and the significance of this phenomenon in endogenous depression are discussed.
The present experiments report the existence of an apico-basal plasma membrane shuttle in cultured renal collecting duct principal cell epithelium. Apical and basal perfusion under isotonic conditions, 290 mosm phosphate-buffered saline (PBS), has no effect on the shape of the epithelium. In contrast, gradient perfusion of the epithelium with 75 mosm PBS on the apical side and 290 mosm PBS on the basal side for 10 min alters the morphology of the epithelium by causing the originally columnar epithelial cells to become lower, the intercellular spaces to dilate, and the intracellular vesicles to enlarge. Perfusion of the epithelium with isotonic PBS in the presence of electron-dense cellular markers such as gold-coupled GPCDI antibody, recognizing a glycoprotein in the plasma membrane of collecting duct cells (W.W. Minuth, G. Lauer, S. Bachman and W. Kriz, Histochemistry 80:171-182, 1984), cationized ferritin (CF), horseradish peroxidase (HRP) and native ferritin (NF) for 10 min reveals their binding at the apical plasma membrane. Little endocytosis is observable. However, after labeling the luminal side by the cellular markers and following exposure to apical hypotonicity, 75 mosm PBS for 10 min, endocytosis of all markers is enhanced to a high degree. Furthermore, the gold-coupled GPCDI antibody and cationized ferritin are transported within vesicles unidirectionally through the epithelium and are exocytosed at the basolateral aspect, indicating the retrieval and possible translocation of apical plasma membrane. In contrast, volume markers such as NF and HRP are also endocytosed under osmotic gradient exposure, but are not seen to be transcytosed. Therefore, the function of this membrane pathway seems not to be related to water reabsorption, but may be part of a cellular response as protection against the osmotic gradient.
In the present study, we were particularly interested in distinguishing specific patterns of structural and functional proteins in the collecting duct system of neonatal and adult kidneys and in cultured renal collecting duct epithelia in order to ascertain the degree of differentiation in the cultures. We studied the distribution of specific renal collecting duct cell markers using morphological, immunohistochemical and biochemical procedures. Cultured renal collecting duct epithelium undergoes maturation in vitro. Examples of morphological differentiation include the appearance of cilia and microvilli at the apical cell pole, and a basement membrane at the basal aspect of the epithelium. Tight junctions with five to seven strands separate the wide intercellular spaces from the apical cell surface. Physiological maturation from a 'leaky' to a 'tight' epithelium is evident from the acquisition of the alpha-subunit of Na/K-ATPase and the development of a high transepithelial potential difference and resistance. Biochemical differentiation is revealed by the expression of specific proteins. The simple-epithelium cytokeratins, PKK1 and PKK2, which are typical intracellular-matrix proteins of mature collecting duct epithelium, maintain the same distribution in cell culture as in neonatal and adult kidneys. An indicator of maturation in vitro is the expression of the collecting duct-specific proteins, PCD2 and PCD3. Newly developed monoclonal antibodies against these antigens reacted similarly with cultured cells and cells of the mature collecting duct system, but they did not label the embryonic ampullae in the cortex of neonatal rabbit kidneys. In contrast, a third collecting duct-specific protein, PCD1, is not expressed by the cultured cells, which indicates the retention of an embryonic characteristic in vitro. Embryonic collecting duct ampullae of the neonatal kidney in situ contain laminin during their development. Laminin is, however, absent in cultured collecting duct epithelium. Biochemical stimulation of the adenylate cyclase system by arginine vasopressin resulted in a twofold stimulation of the enzyme activity. This degree of stimulation is similar to that found in maturing kidneys of neonatal rabbits and indicates another embryonic feature of the cultures.
A sulfated, proline-rich glycoprotein (gpCDI, apparent molecular weight 200,000 in column chromatography and 150,000 in SDS-PAGE) was isolated from cultured renal collecting duct epithelium by centrifugation. Triton X100 extraction and DEAE-cellulose ion exchange chromatography. A DEAE-cellulose ion exchange chromatography fraction with the enriched gpCDI was used for immunization of guinea pigs. The antiserum was prepared for antigen localization by indirect immunofluorescence in collecting duct cell cultures and in tissue sections of neonatal and adult rabbit kidneys. In the cultured collecting duct epithelium, antibody staining of the epithelium and structures of the extracellular matrix was age dependent. Cultures of dedifferentiated collecting duct monolayers revealed positive reaction in the cytoplasm. In neonatal and adult rabbit kidneys, the antibody was localized in the entire collecting duct system but not in the collecting duct ampullae of the newborn kidney. Staining of the cytoplasm was found only in medullary collecting ducts of the neonatal kidney; other portions revealed staining mostly at the basal circumference of the tubule and at the luminal cell borders. Apart from collecting ducts, no other tubular segments were reactive. The cortical and the medullary interstitium contained fluorescent fibres which were concentrated around vascular structures. A possible relation between gpCDI and collagenous compounds is discussed. Bowman's capsule reacted positively, whereas staining of the mesangial matrix was weak. The localization of the antigen, as revealed by indirect immunofluorescence, suggests that gpCDI occurs both in intracellular and extracellular (interstitial) location. Two main points are emphasized: Firstly gpCDI is considered an important constituent in different stages of collecting duct development, and secondly, the staining pattern of the antibody varies with the different portions of both young and adult kidney collecting ducts; this staining heterogeneity may correspond with the known regional differences of collecting duct functions.
In a lysogen, most genes of phage lambda are repressed; in response to a transient induction signal, they are efficiently switched on. The switch, which consists in part of a tripartite operator to which two regulatory proteins bind, depends not only on DNA--protein interactions, but also on effects transmitted from one DNA-bound protein to another. lambda Exemplifies a strategy that facilitates efficient switching between two physiological states in response to a transient signal.
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In this paper we describe a method for constructing E. coli plasmids that direct efficient expression of genes that encode eucaryotic or procaryotic proteins. No functional assays for the proteins are needed, and they are produced in their native, unfused state. The only requirement is that the genes be isolable without intervening sequences. We describe as an example the construction of a plasmid that directs the synthesis of about 10,000-15,000 monomers per cell of rabbit beta-globin. The essential steps in a typical construction are as follows. --A region of the gene encoding the amino-terminal portion of the protein is fused to DNA encoding an enzymatically active carboxy terminal fragment of beta-galactosidase. The latter is carried on one of three plasmids designed to facilitate the fusion (the construction of these three plasmids is described in the Appendix). --A "portable promoter" of the lac operon is placed at many positions in front of the fused gene using nucleases in vitro. Those promoter placements that elicit efficient expression of the fused gene are identified by the beta-galactosidase activity that they express. (In the special case we describe, plasmids identified as directing efficient expression of beta-globin were found to bear "hybrid" ribosome binding sites consisting of the Shine-Dalgarno sequence carried on the promoter fragment and the ATG of the beta-globin gene.) --The gene of interest is reconstituted intact, with the portable promoter in place, by recombination in vitro or in vivo.
In 240 autopsy cases of both sexes, aged between 19 and 88 years and with no evidence of clinically manifest bone disease, the structure of the spongy bone and the external form of the 3rd and 5th lumbar vertebrae were investigated quantitatively and morphometrically on the basis of high-contrast X-ray images of 100 mu-thick polished bone sections, using the Leitz texture analysis system. The structure of the spongy bone was analysed on the basis of the parameters volumetric density, surface density and specific surface in horizontal "fifths", the form being determined by measuring the greatest and smallest heights and widths. In the individual "fifths", the structural parameters manifest a "stepped" distribution, the highest values being in the outer, the lowest values in the middle "fifths". With increasing age, this distribution pattern flattens to differing degrees so that, in old age, only the outer"fifths"differ from the middle and inner"fifths". The form parameters of the vertebrae reveal an age-independent constant heigh and an age-dependent increase in maximum width. The vertebral bodies are subjected mainly to compressive forces and represent a compound construction of spongy bone and fluid-filled medullary cells. The inhomogeneity of the vertebral structure is the constructional equivalent of the intravertebrally regionally differing mechanical forces. Also the structure of the residual spongy bone resulting from the age-dependent remodelling process, is oriented to these mechanical forces. Despite the considerable intravertebral remodelling of structure, the form of the vertebral bodies remains largely constant. The increase in maximum width is based on an increase in the tensile forces acting upon the outer edges of the vertebral bodies consequent upon degenerative intervertebral disc changes.
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