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M Bauer

Publications and source records attributed to M Bauer.

At least 361 records · Page 20Linked to original sources
PubMed1995

The X-ray crystal structure of thrombin in complex with N alpha-2-naphthylsulfonyl-L-3-amidino-phenylalanyl-4-methylpiperidide: the beneficial effect of filling out an empty cavity.

The 2.5 Angstrum structure of bovine epsilon-thrombin in complex with N alpha-2-naphthyl-sulfonyl-L-3-amidinophenylalanyl-4-methylpiper idide (L-NAPAMP) was solved and crystallographically refined to an R-value of 0.19. The L-NAPAMP moiety is completely and unambiguosly defined in the electron density. NAPAMP binds almost identical to the related 4-methyl deficient 3-amidino-phenylalanyl derivative TAPAP. The overall binding geometry appears dominated by the fixation of the 3-amidinophenyl ring in thrombin's S1-pocket and the hydrogen bonds to Gly 216, irrespective of the presence or absence of a substituent in the 4-position of the piperidine ring. The additional 4-methyl group gives rise to a 17-fold better binding. The more complete spatial occupancy of the hydrophobic S2-cavity therefore accounts for a decrease in free energy of binding of 15 kcal/mol, a value comparable with that anticipated for filling up a stable empty cavity of similar size by a methyl group.

Alanine↗
PubMed1995

Chronic ethanol consumption increases hepatic sinusoidal contractile response to endothelin-1 in the rat.

Recent evidence suggests that hepatic stellate cells function as liver-specific pericytes that are highly contractile in response to endothelin-1 (ET-1). Liver injury has been shown to lead to "activation" of stellate cells producing a phenotypic change to a more myofibroblastic cell type including loss of vitamin A and increased contractility. The present study was undertaken to test the effects of short-term chronic ethanol consumption (36% of total calories for 5 weeks according to the Lieber-DeCarli protocol) on hepatic vitamin A storage, expression of smooth muscle alpha-actin, and sinusoidal contractility in Sprague-Dawley rats. Using in vivo epifluorescence video microscopy, we quantified the number of sites of vitamin A fluorescence (purportedly stellate cells) and assessed sinusoidal microhemodynamics at baseline and during a 20-minute infusion period of ET-1 (1 pmol * 100 g body weight [bw]*1*min-1). Retinol and retinyl palmitate were measured after the experiment by means of high-pressure liquid chromatography (HPLC). A highly significant decrease in liver retinyl palmitate level (control: 622.5 +/- 50.9; ethanol: 273.0 +/- 38.0 microgram/g liver; P< .001) was found that correlated with a decrease in sites of vitamin A fluorescence (control: 531.4 +/- 76.1; ethanol: 141.1 +/- 30.2* mm-2; r = .82, P <.001). Concomitantly scattered expression of smooth muscle alpha-actin in sinusoids was observed. Although sinusoidal hemodynamics were not affected at baseline, a significant increase in sinusoidal contractility on endothelin-1 infusion (e.g., sinusoidal resistance [% of baseline value]: control: 10 minutes: 288.7 +/- 71.7, 20 minutes: 200.5 +/- 46.9; ethanol: 10 minutes: 1,916.0 +/- 701.7, 20 minutes: 656.8 +/- 103.3; P < .05 and .01, respectively) was observed. These data indicate that chronic ethanol consumption in this moderate model initiates stellate cell activation. Increased sinusoidal responsiveness to the vasoconstrictor ET-1 in vivo may contribute to the increased susceptibility of ethanol-fed rats to secondary stresses that increase ET-1 expression, such as endotoxemia.

Actins↗
PubMed1995

[Intimate relations and the course of psychiatric disorders in relocated patients].

In this study we investigated empirically the association between close relationships and the course of psychiatric disorders in 94 persons who moved from the GDR to West Berlin in 1989 and showed psychiatric disorders after their arrival. The patients mostly suffered from anxious and depressive symptoms accompanied by vegetative complaints. Symptoms were clearly reduced within the follow-up period (follow-up interviews after 6 months and 2 1/2 years). There were moderate correlations between family situation and the degree of symptoms. The mere existence of a partnership was not found to influence improvement. Negative change of partnership, and more quarreling was associated with a more unfavorable course of illness. Living with children was correlated with more symptoms--particularly six months after migration--and may be an additional stress factor for successful adaptation.

Acculturation↗
PubMed1995

Myoclonus in patients treated with clozapine: a case series.

BACKGROUND: Various types of movement disorder have been reported to occur rarely in patients treated with clozapine. This paper describes five cases in which these phenomena appeared to be clearly associated with clozapine medication and discusses possible pharmacologic mechanisms and treatment options. METHOD: Inpatients receiving clozapine were investigated for the presence of movement disorders. We present five patients with clozapine-induced myoclonus, describe their patterns, and compare clinical features. RESULTS: Five patients treated with clozapine developed a similar pattern of movement disorder that can be described as myoclonus. The neurologic symptoms improved after the treatment was discontinued, the clozapine dose reduced, or concomitant carbamazepine administered. CONCLUSION: Clozapine can induce dose-dependent myoclonus. However, these symptoms can be relieved by reducing the dose of clozapine or giving carbamazepine so that discontinuation of clozapine treatment can be avoided.

Adult↗
PubMed1995

Conserved machinery of the bacterial flagellar motor.

Novel periplasmic and cytoplasmic structural modules of the bases of bacterial flagella have been observed in situ and isolated using new biochemical protocols. Flagellar rotation may depend upon interactions of these modules with the intramembrane particle rings, a ubiquitous feature of flagellar bases necessary for torque generation. The outer membrane-associated basal disk of the Wolinella succinogenes polar flagellum has architecture well suited for interaction with the ring particles. However, antibody against the main W. succinogenes basal disk protein did not cross-react with flagella-enriched fractions from Salmonella typhimurium and Bacillus firmus; nor have such structures been observed in these species thus far. Antibodies against two S. typhimurium proteins, FliG and FliM, known to be involved in motor function and part of the cytoplasmic module in this species cross-reacted with flagella-enriched fractions from both W. succinogenes and B. firmus. In addition, flagellar cytoplasmic structure could be isolated from B. firmus. The basal disk may anchor the flagellar motor to the cell wall in some polar bacteria, but this does not seem to be a unique strategy. In contrast, the data indicate that the cytoplasmic module is conserved.

Antigens, Bacterial↗
PubMed1995

Effect of anti-tumor necrosis factor alpha on leukocyte adhesion in the liver after hemorrhagic shock: an intravital microscopic study in the rat.

Tumor necrosis factor (TNF) plays a well known role during the development of multiple organ failure, in part due to its role for the expression of adhesion molecules on endothelial cells, thereby contributing to inflammatory reactions. The purpose of this study was to investigate the effects of TNF on leukocyte-endothelial interactions in the liver as a key organ during the systemic inflammatory response syndrome. In Sprague-Dawley rats (n = 6/group) hemorrhagic shock was induced by reduction of the mean arterial blood pressure (MAP) to 40 mmHg for 45 min; resuscitation was initiated by retransfusion of shed blood (60%) and Ringer's lactate. At 1 and 5 h after resuscitation, intravital microscopy of the liver was performed after injection of acridine orange as marker of leukocytes in sham-control animals and in shock animals pretreated with anti-TNF monoclonal antibody (2 mg/kg b.w. TN3; Celltech, Slough, UK) or NaCl .9% 2 h prior to shock induction, respectively. At constant systemic hemodynamic conditions in all groups (e.g., normal MAP), sinusoidal diameters and sinusoidal blood flow were comparably decreased to approximately 75% of control values in all shock groups. Significant differences were observed particularly in respect to permanent adherent leukocytes with 31.8 +/- 4.7% in the shock/NaCl group and 20.7 +/- 2.6% (mean +/- S.E., p < .05) in the shock/TN3 group 5 h after resuscitation following hemorrhagic shock. Consistently higher adhesion rates were observed in the portal regions compared to pericentral regions of the liver lobules.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

[The self concept and personality structure of alcohol intoxicated drivers: how do they see themselves, and how are they judged by others?].

Assessing the problem of "alcohol in road traffic" it becomes apparent that most offenders have high BACs (in excess of 1.6 per mille) and that they are repeating offenders. It can therefore be assumed that those people are drink-drivers, which means that, when assessing the offence, the offender's personality as a whole has to be taken into consideration. The DUI offenders themselves usually justify the offence by balming it on the circumstances of a given situation. On the basis of this discrepancy, the published study deals with the question of whether there are any differences between the way DUI offenders judge their personality and self concept and the way other people do. This also leads to the questions of whether the number of offences play a role or not. The self image of 60 male DUI offenders was rated by means of the Giessen test and the Frankfurt self concept scales "problem solving", "confidence in behaviour and decision making", as well as "judgement by others". For the outside judgement, 60 male volunteers were asked to judge DUI convicted drivers. It showed that the DUI convicted drivers assessed their personality to be no different than that of the average person. Their self concept was characterised by positive attributes. However, the outside judgement showed them to be less socially responsive, lacking self control, as well as rather dominant, depressive, reserved and rather inhibited in heterosexual relationships. The self judgement changes with an increasing number of offences, as does the outside judgement to an even greater extend. The latter turns into a more negative judgement. Regarding the self concepts, only the outside judgement proved to be more negative. The number of convictions didn't influence the DUI offenders' self estimation.

Adult↗
PubMed1995

[Effect of treatment of patients with sleep apnea with a nCPAP device on stress coping and well-being].

This study analyzed the influence of CPAP-Treatment on stress coping and well-being in sleep apnea patients. 20 patients with sleep apnea were examined using a stress coping questionnaire ("Stressverarbeitungsfragebogen" of Janke, Erdmann, and Kallus, 1985) and the Scale of Well-Being ("Befindlichkeitsskala" of von Zerssen, 1976). Results showed an improvement in the stress coping mechanism following CPAP treatment. In addition, prior to treatment apnea patients exhibited significantly worse mood compared to that of the control group. Treatment with CPAP significantly improved the mood of apnea patients.

Adaptation, Psychological↗
PubMed1994

PET1402, a nuclear gene required for proteolytic processing of cytochrome oxidase subunit 2 in yeast.

The nuclear mutation pet ts1402 prevents proteolytic processing of the precursor of cytochrome oxidase subunit 2 (cox2) in Saccharomyces cerevisiae. The structural gene PET1402 was isolated by genetic complementation of the temperature-sensitive mutation. DNA sequence analysis identified a 1206-bp open reading frame, which is located 215 bp upstream of the PET122 gene. The DNA sequence of PET1402 predicts a hydrophobic, integral membrane protein with four transmembrane segments and a typical mitochondrial targeting sequence. Weak sequence similarity was found to two bacterial proteins of unknown function. Haploid cells containing a null allelle of PET1402 are respiratory deficient.

Alleles↗
PubMed1994

SP- and CGRP-immunoreactive axons differ in their ability to reinnervate the skin of the rat tail.

The reinnervation of cutaneous targets was studied in the rat tail after proximal lesions of all collector nerves. The distribution of immunofluorescent nerve fibres stained for calcitonin-gene-related peptide (CGRP) and substance P (SP) was examined after 110-210 days. Targets at all sites were reinnervated by CGRP-immunoreactive (IR) fibres. However, SP-IR terminals were rare, particularly distally, despite staining within subdermal nerve trunks.

Animals↗
PubMed1994

[Intraspinal neurinoma in the thoracolumbar junction presenting unusual symptoms. The differential diagnosis of lumbago].

After more than a year of persistent lumbosacral pain a 53-year-old woman suddenly developed unilateral monoradicular pain over the S1 dermatome. Neurological, general medical and biochemical examinations were unremarkable, but myelography and magnetic resonance imaging revealed a cystic intraspinal space-occupying lesion at the level of L1, which was completely excised surgically. It proved to be a neurinoma, 5 x 3 x 3 cm, completely filling the spinal canal at the junction between the conus medullaris and the cauda equinus. The patient was without symptoms and neurological deficit after the operation. The tumour having been completely removed, the prognosis is good.

Diagnosis, Differential↗