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E Bauer

Publications and source records attributed to E Bauer.

At least 91 records · Page 5Linked to original sources
PubMed1994

The 100-kDa chain of nicein/kalinin is a laminin B2 chain variant.

We have isolated the basement membrane component nicein and performed rotary-shadow analyses using electron microscopy that showed the presence of two forms (I and II) of the protein. Molecular cloning of the cDNA that codes for the 100-kDa chain of the protein revealed that the sequence matches those independently identified for the 105-155-kDa subunit of kalinin, a recently identified basement membrane component. These data demonstrate that nicein and kalinin contain an identical chain. The length of the open reading frame in the cDNA (approximately 5200 nucleotides) and amino acid sequence obtained from the N-terminus of the 105-kDa kalinin chain showed the occurrence of a precursor polypeptide. This immature polypeptide is probably related to form I, observed by rotary shadowing, while the mature form is related to form II. It is noteworthy that nicein/kalinin subunits share discrete sequence similarities with the B2 chain of human laminin, but with a cleavage occurring within domain III that eliminates domains IV and V from the final product. The sequence of this subunit is nearly identical to that of B2t, a recently described polypeptide supposed to be related to a new laminin variant. Since nicein/kalinin expression is specifically impaired in the severe genodermatosis Herlitz junctional epidermolysis bullosa, the role and structure of this tissue-restricted laminin variant is crucial for the understanding of epidermal-dermal adhesion.

Amino Acid Sequence↗
PubMed1994

Thrombin-induced endothelium-dependent inhibition and direct activation of platelet-vessel wall interaction. Role of prostacyclin, nitric oxide, and thromboxane A2.

BACKGROUND: Platelet-vessel wall interaction plays an important role in acute cardiovascular disorders. Thrombin is a potent platelet activator but also has profound effects on the endothelium. Endothelial cells possess antithrombotic activity by releasing nitric oxide and prostacyclin, both potent vasodilators and platelet inhibitors. We studied the role of thrombin as a regulator of platelet-vessel wall interaction in isolated human arteries suspended in organ chambers for isometric tension recording. METHODS AND RESULTS: In arteries with endothelium, thrombin (0.01 to 1 U/mL) induced endothelium-dependent relaxations, which were reduced by the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 10(-4) mol/L) and/or indomethacin (10(-5) mol/L). Human platelets (75,000/microL) evoked only marginal contractions in arteries with endothelium (3 +/- 3% of the contraction to KCl 100 mmol/L; NS), which were markedly enhanced by endothelial removal (22 +/- 4%; P < .05). Thrombin (1 U/mL) did not affect the response to platelets in arteries with (6 +/- 5%; NS) but induced a huge contraction in rings without endothelium (53 +/- 6%; P < .01 versus control without endothelium). The potent contraction to thrombin-activated platelets (1000 to 75,000/microL) in arteries without endothelium was markedly inhibited by the thromboxane A2 synthetase/receptor antagonist ridogrel (10(-5) mol/L; P < .005 versus control) and the single-acting thromboxane receptor blocker SQ-30741 (10(-7) mol/L; P < .01 versus control). CONCLUSIONS: Thus, thrombin directly stimulates platelets to release thromboxane A2, inducing potent vasoconstriction, which is prevented by the simultaneous thrombin-induced release of prostacyclin and nitric oxide from endothelial cells. In arteries devoid of functional endothelial cells, as occurs in patients with coronary artery disease, a combined inhibition of thromboxane production and action provides a potent therapeutic tool to interfere with the thrombin-induced activation of platelet-vessel wall interaction.

Coronary Vessels↗
PubMed1993

Zatebradine: pharmacokinetics of a novel heart-rate-lowering agent after intravenous infusion and oral administration to healthy subjects.

Zatebradine (1; UL-FS 49 CL; 1,3,4,5-[tetrahydro-7,8-dimethoxy-3-[3-[ [2-(3,4-dimethoxyphenyl)ethyl]methylamino]propyl]-2H-3-benzazepin- 2-on- hydrochloride) is the proposed INN name for a nonchiral, novel, specific heart-rate-lowering drug that is suitable for the treatment of stable angina pectoris. The pharmacokinetics of 1 and of total radioactivity in healthy volunteers (n = 6) were determined after intravenous infusion and oral administration of an experimental drug solution containing 7.5 mg (1.85 MBq) of 14C-labeled drug. Concentrations in plasma and urine were measured by a specific, sensitive, reversed-phase automated high-performance liquid chromatography system with fluorimetric detection at 285 nm Ex, 315 nm Em and by liquid scintillation counting. Recovery of total radioactivity was 89.8 +/- 2.3% (infusion) and 92.2 +/- 3.0% (oral). Renal elimination of total radioactivity was 62.5 +/- 2.0% (infusion) and 48.8 +/- 3.1% (oral). After intravenous infusion and oral administration, 27.3 +/- 2.4 and 43.4 +/- 3.9%, respectively, of the administered dose was eliminated in the feces. Absorption, based on renal excretion of total radioactivity following oral and intravenous dosing, was 79.2 +/- 15.3% (mean +/- standard deviation). Unchanged parent drug contributed 28.4 +/- 5.8% (infusion) and 12.4 +/- 3.7% (oral) of the dose to renal excretion. Zero to three minutes after cessation of the 20-min infusion, the maximum concentration of parent drug in plasma was 161.9 +/- 70.9 ng/mL. After oral administration, a mean peak concentration in plasma of 24.3 +/- 6.7 ng/mL (0.5-3 h postadministration) was reached. Data regarding levels of 1 in plasma could be adequately fitted with an open, two-compartment model.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1993

Infected endocardial pacemaker electrodes: successful open intracardiac removal.

UNLABELLED: The long-term results after open intracardiac removal of infected pacing electrodes are presented. METHODS: Between 1985 and 1990 open intracardiac removal of 19 infected pacing electrodes was performed in seven patients (six male and one female), with a mean age of 56 years. The indications were: persisting bacteremia in three; generator pocket infection in four; endocarditis in one; and ventricular tachycardia caused by retracted electrodes in one. All electrodes were fixed in the right heart and extraction by closed methods failed. Percutaneous catheter techniques were not applied in these seven patients. In five patients two ventricular electrodes had to be removed, and in two patients a single one. A total of seven atrial electrodes were removed in six patients (one electrode each in five patients; two electrodes in one patient). All atrial and two ventricular electrodes could be removed through a pursestring suture without use of a pump oxygenator. For the removal of ten ventricular electrodes in six patients (two electrodes each in four patients; 1 electrode each in two patients) a right-sided atriotomy was necessary with cardiopulmonary bypass (CPB). Simultaneously, five new pacing systems were implanted. RESULTS: There were no early or late mortalities. In January 1991, all seven patients are alive and in a mean New York Heart Association Class 1,3 of heart failure after a mean interval of 33 months. In all cases the infection could controlled with a simultaneous antimicrobial chemotherapy and the postoperative period was free of major complications. CONCLUSION: Open intracardiac removal of retained pacing electrodes with or without use of CPB is a safe procedure without major complications. It is mandatory for all infected pacing electrodes that cannot be extracted by closed methods.

Adult↗
PubMed1993

Cytolytic cross-reactive antibodies directed against the cardiac membrane and viral proteins in coxsackievirus B3 and B4 myocarditis. Characterization and pathogenetic relevance.

BACKGROUND: Coxsackievirus B3 and B4 (CVB) myocarditis was assessed by a more than twofold change in titer of the microneutralization tests against enteroviruses within 3 weeks in all patients, by an endomyocardial biopsy indicative of active myocarditis in eight cases, and by pericardial effusion and acute cardiomegaly in two patients. In all endomyocardial biopsies, immunoglobulin binding to the sarcolemma and to the interstitial tissue was demonstrated irrespective of an infiltrate being at the same focus or not. IgG binding was found in nine, IgM and IgA in seven, C3 in C1q in three, and C5b9 in three of 10 patients. In addition, circulating antimyolemmal antibodies (AMLAs) were demonstrated regularly. METHODS AND RESULTS: In this study, for the first time adult human myocytes isolated from atrial appendages during open-heart surgery were used as antigen in the indirect immunofluorescence test: nine of 10 sera of patients with CVB myocarditis demonstrated AMLAs of the homologous type in titers of 1:40-1:320, whereas eight of 10 reacted with rat myocytes (heterologous type) only. Circulating AMLAs fixed complement component C4 in the majority of cases. During the in vitro assay of antibody-mediated cytolysis with vital heart cells, fixation of components C3, C4 to the myolemma in all, of C1q in seven, and of the C3b9 complex in eight of 10 sera was demonstrated after addition of a fresh complement source, indicating the potential of a complement-mediated cytolysis being operative. In vitro cardiocytolysis of isolated adult rat heart cells is present in the untreated sera of patients with enteroviral myocarditis and is abolished after adsorption of sera with CVB and with isolated rat heart cells. This indicates functional cross-reactivity of the antimembrane antibodies. To analyze further the cross-reactive epitopes, sodium dodecyl sulfate gel electrophoresis of human and rat sarcolemma and consecutive immunoblots were performed. Cross-reactivity between viral (CVB) and sarcolemmal epitopes could be demonstrated to bands of 220 kd in 10%, 110 kd in 50%, 48 kd in 40%, 35 kd in 40%, and 31 and 28 kd in 30% each. Cardiospecific non-cross-reactive epitopes for antisarcolemmal antibodies or AMLAs were membrane proteins of 90 kd and 78 kd in 50%, 72 kd in 90%, 67 kd in 40%, and 45 kd in 50%. Virus-specific antibody binding sites for sera included proteins of 33 and 34 kd. CONCLUSIONS: Western blot analysis of sera incubated with cardiac membranes or enteroviral proteins demonstrated that the antibodies are directed to defined epitopes of the sarcolemma. Some antibodies were cross-reactive to enteroviral proteins, indicating that enteroviral infection may be the etiological trigger of an autoreactive myocarditis. The cytolytic property of the patients' sera in vitro suggests in addition that humoral autoreactivity and antigenic mimicry are major pathogenetic principles operative in human enteroviral myocarditis and its sequelae.

Adsorption↗
PubMed1992

New aspects in the staging of lung cancer. Prospective validation of the International Union Against Cancer TNM classification.

BACKGROUND AND METHODS: To validate the new TNM definitions for lung cancer (International Union Against Cancer [UICC] TNM classification, 4th edition, 1987), the data of 3823 patients were analyzed prospectively in terms of concordance between clinical (TNM) and pathologically confirmed classification (pTNM), the value of the various diagnostic techniques in estimating the pathologically confirmed classification, and the prognostic relevance of the new TNM definitions. RESULTS: With regard to the primary tumor (T), clinical and pathologic classifications were identical in 63%; with regard to lymph node involvement (N), the agreement was 47%; for distant metastasis agreement occurred in 91% of cases and for the stages it occurred in 56%. As to the primary tumor (T), the accuracy of radiography (59%) was nearly identical to that of computed tomography (CT) (58%). Both techniques were less precise in determining the extent of lymph node involvement (CT, correct assessments in 50%; radiography, correct assessments in 43%). The statistically significant differences in the prognosis for the T, N, and M categories and for the stages and the categories of the new R classification could be confirmed. Allowance should be made for the different prognosis between T1N0M0 and T2N0M0 by the new Substages IA and Ib of Stage I. CONCLUSIONS: By the new TNM definitions for bronchus carcinoma, international conformity became feasible and practical, and the improvement of its prognostic relevance provided a more reliable basis for establishing guidelines for individual oncologic concepts.

Bronchial Neoplasms↗
PubMed1992

[Pericardectomy and acute infectious pericarditis].

Between 1980 and 1990 12 patients (5 male, 7 female) were operated on for acute infectious pericarditis at a mean age of 42 years. The infections were 6 bacterial (purulent 4, abscess 2), 4 tuberculous, 1 viral and 1 Candida. Pericarditis resulted from contiguous spread of infection from bilateral pneumonia in 3 patients, from subphrenic abscess in 2 and followed bacteremia in 1. Clinical signs were: tamponade/shock in 9, elevated jugular venous pressure in 11, edema in 6, hepatomegaly in 6, ascites in 1, and pericardial friction rub in 3. A preoperative pericardiocentesis in 9 patients allowed only 4 positive microbiological diagnoses and was an insufficient drainage in all cases. The preoperative mean NYHA class was 3.3. The pericardectomy was total in 9 patients and partial in 3. Total mortality was 1/12 patients (8%) with one late death due to recurrent tuberculous pericarditis. No patient with purulent pericarditis died. Another recurrence occurred 6 months after acute viral pericarditis. Atrial fibrillation in one patient was the only postoperative complication. After a mean follow-up period of 48.5 months no cardiac constriction had occurred in 11 surviving patients Actuarial survival after pericardectomy is 100% after 1 month and remains 91% after 5 years. The mean NYHA class has significantly improved to 1.2 (p less than 0.05) at the end of the follow-up. We conclude that pericardectomy combined with a specific antimicrobial therapy is a safe treatment for acute infectious and especially purulent pericarditis with low mortality and excellent longterm results. Early pericardectomy allows rapid decompression of the heart, removal of intrapericardial adhesions and infected tissue and prevents late constriction.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗