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B Henkel

Publications and source records attributed to B Henkel.

At least 19 recordsLinked to original sources
PubMed1992

Chicken vigilin gene organization and expression pattern. The domain structure of the protein is reflected by the exon structure.

Chicken vigilin was identified as a member of an evolutionary-conserved protein family with a unique repetitive domain structure. 14 tandemly repeated domains are found in chicken vigilin, all of which consist of a conserved sequence motif (subdomain A) and a potential alpha-helical region (subdomain B) [1]. We have established the physical structure of the chicken vigilin gene by restriction-fragment analysis and DNA sequencing of overlapping clones isolated from a phage lambda genomic DNA library. The chicken vigilin gene is a single-copy gene with a total of 27 exons which are distributed over a region of some 22 kbp. Exon 1 codes for a portion of the 5' untranslated region, exon 2 contains the translation start point and forms, along with exons 3 and 4, the N-terminal non-domain region. Exons 5-25 encode the vigilin domains 1-14 and the remaining exons 26 and 27 contain the non-domain C-terminal as well as the untranslated regions. The domain structure of the protein is reflected in the positioning of introns which demarcate individual domains. While domains 1-3 and 8-10 are each encoded by a single exon (5-7, 16-18); all other domains are contained in a set of two exons which are separated by introns interspersed at variable positions of the DNA segment coding for the conserved sequence motif. In conclusion, the data presented suggest that the chicken vigilin gene evolved by amplification of a primordial exon unit coding for the fundamental bipartite vigilin domain.

Animals↗
PubMed1992

Complete cDNA sequence of chicken vigilin, a novel protein with amplified and evolutionary conserved domains.

The complete cDNA (4375 bp), coding for a new protein called vigilin, was isolated from chicken chondrocytes. The cDNA shows an open reading frame of 1270 amino acids which are organized in 14 tandemly repeated homologous domains. Each domain consists of two subdomains, one with a conserved sequence motif of 35 amino acids (subdomain A) and another one with a presumptive alpha-helical structure of 21-33 amino acids (subdomain B). 149 amino acids at the N-terminus and 71 amino acids at the C-terminus of vigilin do not show the characteristic domain structure. No sequence characteristic of a signal peptide has been found, which argues for an intracellular localisation of vigilin. Vigilin is highly expressed in freshly isolated chicken chondrocytes but little in chondrocytes after prolonged time in culture. Vigilin mRNA exists in two size species, 4.4 kb and 6.5 kb in length due to the usage of different polyadenylation sites. Comparison of the vigilin sequence with data bases showed a remarkable similarity to protein HX from Saccharomyces cerevisiae [Delahodde, A., Becam, A. M., Perea, J. & Jacq, C. (1986) Nucleic Acids Res. 14, 9213-9214]. The yeast protein consists of eight homologous domains with 11 conserved amino acid residues within a set of 35 amino acids. The N-terminal and C-terminal regions of vigilin and protein HX do not reveal any sequence similarity. These results, together with the demonstration of the characteristic vigilin sequence motif in a human cDNA clone, suggest that the repeats represent evolutionary conserved autonomous domains within a family of proteins found in yeast, chicken and man.

Amino Acid Sequence↗
PubMed1992

Standardized noninvasive assessment of myocardial free fatty acid kinetics by means of 15-(p-iodo-phenyl) pentadecanoic acid (123I-pPPA) scintigraphy: II. Clinical results.

Our results establish that myocardial regions supplied by a significantly stenosed coronary vessel can be distinguished with high statistical significance from healthy regions on account of changes in the myocardium/background ratio, i.e. a reduction of regional uptake of 15-(p-iodo-phenyl) pentadecanoic acid (pPPA). The statistical significance applies to patients with coronary artery disease (CAD), to all examined CAD areas without areas of infarction as well as to infarcted regions. Our results also confirm the suitability of labelled fatty acids, such as pPPA, for the visualization of damaged myocardial regions. The results further indicate that pPPA practically is of comparable value to 201Tl with regard to their respective qualities as 'static' imaging agents for the heart muscle. This study, with the help of a simultaneous analysis of regional myocardial perfusion rates (rMBF) and of a parameter for the metabolism of fatty acids, practised here for the first time, could demonstrate interindividual differences between patients and groups of patients with a correlation between perfusion and the utilization of pPPA in patients with CAD. The reciprocal of the rMBF, the mean transit time (MTT), was significantly prolonged after stress in patients with CAD (P less than 0.05), suggesting impaired 'microcirculation' in the patient group. The determination of elimination half-lives (T1/2) contributes little if any information towards delineation of cardiac disease entities. The wide overlap of T1/2 values between various clinical syndromes and entities with extreme standard deviations remained an annoying problem in our studies. Nevertheless, certain trends in T1/2 behaviour could be recorded, but they did not yield any statistical significances, because of the high degree of individual variability. A considerable variability of T1/2 values among healthy controls was recorded as well as intra-individually in different regions of the heart muscle. The wide range of 'normal' values rendered statistical evaluation almost, if not entirely, impossible. It appears that the high degree of variability results amongst others, from technical shortcomings in the external recording instruments, i.e. gamma cameras, as well as from the presence of interfering alternate substrates such as glucose and lactate. Nevertheless, the wide range of measured results in healthy control subjects suggests the presence of a considerable regional intra-individual heterogeneity of cardiac substrate metabolism. One must therefore accept, at least in our opinion, that T1/2 values are not sufficiently reliable as an indicator of myocardial metabolism and are of little value with respect to clinical diagnostic considerations and to prognosis as well. Possible explanations for this finding are offered and discussed in this paper.

Adult↗
PubMed1990

Physicochemical characterization of tetraether lipids from Thermoplasma acidophilum. V. Evidence for the existence of a metastable state in lipids with acyclic hydrocarbon chains.

The main glycophospholipid of Thermoplasma acidophilum, grown at 39 degrees C, is composed of a di-isopranol-2,3-glycerotetraether. It has been characterized in hydrated systems by calorimetry. Unlike its equivalent grown at 59 degrees C, it shows complex phase properties, which include at least three different phases, (1) a liquid-analogue state (C), which is stable above 20 degrees C, (2) a metastable solid-analogue state (A) formed by supercooling of the liquid-analogue state (C) and (3) a stable solid-analogue state (B), which is slowly formed and may include a close chain packing of lipids and a network of hydrogen bonds between the headgroups. A high fraction of acyclic isopranol chains seems to be a prerequisite for the formation of state (B). A phase diagram, displaying the observed states and the transitions between them is proposed.

Calorimetry↗
PubMed1990

Hemodynamics during PEEP ventilation in patients with severe left ventricular failure studied by transesophageal echocardiography.

The effects of mechanical ventilation with PEEP were investigated in five patients with normal cardiopulmonary function (group A) and in 11 patients with severe left ventricular failure (group B). Cross-sectional area of the right and left atrium (RA/LA), left ventricle (LV), and right ventricle (RV) was determined at EDA/ESA using transesophageal echocardiography. Hemodynamic parameters and transesophageal pressure were measured simultaneously at PEEP levels 0, 4, 8, 12, and 16 cm H2O. End-diastolic area of the right atrium decreased significantly in both groups. The RA pressure increased, while transmural pressure remained unaltered. The CI decreased in both groups. The decrease in cardiac output by PEEP ventilation was related to the decrease in RV filling volume by external compression. In patients with congestive heart failure, PEEP ventilation with 8 to 10 cm H2O did not worsen LV function.

Adult↗
PubMed1986

[Thrombolytic therapy and balloon dilatation. The effect on infarct time, reperfusion and reocclusion].

127 patients, admitted within six hours of onset of symptoms of acute transmural myocardial infarction, received at first 250 000 U streptokinase intravenously over 20 min, followed by an intracoronary infusion of 250 000 U after coronary angiographic demonstration of the infarct vessel. Those in whom the infarct vessel was closed were randomized into two groups. An attempt at recanalization was made either by thrombolysis alone, through a specially developed 3F catheter (group I, 64 patients), or by thrombolysis and dilatation with 4F Grüntzig balloon catheter (group II, 63 patients). There was no significant difference between the two groups with regard to sex, age, infarct site, creatine-kinase level and interval between onset of symptoms and treatment. Re-perfusion rate for group I was 92% (59 patients), for group II 89% (56 patients). Re-occlusion during the hospital stay occurred in 10 of 59 patients in group I, in 9 of 55 in group II. Re-occlusion occurred in only 8% (3 patients) after successful dilatation, but in 35% (6 patients) after failed dilatation. In the subsequent six months further occlusions were observed in seven group I and two group II patients. Combined drug-mechanical recanalization thus increased the re-perfusion rate, shortened the infarction time and made possible full revascularization by subsequent dilatation which led to a reduction in the re-occlusion rate.

Aged↗
PubMed1986

Echocardiographic findings in patients with proved pulmonary embolism.

Echocardiographic studies were performed in 105 patients with acute and recurrent pulmonary emboli. Pulmonary embolism was confirmed by pulmonary angiography (n = 48), autopsy (n = 6), and lung perfusion scintigraphy (n = 51). Seventy of 93 patients (75%) displayed a dilated right ventricle, 38 of 91 patients (42%) had reduced left ventricular cavity dimension, 41 of 82 patients (50%) had a decreased EF slope of the mitral valve, and 78 of 101 patients (77%) showed dilatation of the right pulmonary artery. The motion of the interventricular septum was abnormal in 41 of 93 patients (44%). Right-sided thrombi were seen in 13 patients within the right pulmonary artery (n = 11) and in the right ventricle (n = 3); in one patient they were found in the superior vena cava, in the innominate vein, and the right atrium. Two patients suffered from right-sided endocarditis. Thus echocardiographic changes were frequently found in patients with proved pulmonary emboli. The echocardiographic findings of right-sided cardiac and pulmonary artery abnormalities indicate hemodynamically active pulmonary emboli.

Acute Disease↗
PubMed1986

Stimulus-induced vulnerability in the early and late postinfarction phase.

In 45 survivors of myocardial infarction, cardiac catheterization was performed one and six months after the acute event. After completion of the angiographic investigation, ventricular vulnerability was assessed, using programmed right ventricular stimulation (rates 120 and 140 min-1, single and double premature impulses). In 27/45 patients the results of programmed electrical stimulation were comparable at one and six months. The overall incidence of repetitive ventricular response did not change. There was no correlation between the change of repetitive ventricular response and the change of effective right ventricular refractory period and the change of angiographic parameters (Gensini score, left ventricular ejection fraction and volume indices). It is concluded that between the first and the sixth month after infarction there is no relevant alteration in the propensity to repetitive ventricular response.

Adult↗
PubMed1985

[Normal values for two-dimensional echocardiography].

In 51 normal subjects (26 men, 25 women, age range 15-38 years), normal values for longitudinal axis and diameters of left and right ventricle and left and right atrium were determined by 2-D echocardiography. Both left parasternal longitudinal and cross-sectional cuts were used. Tolerance values to determine normal range were recorded, in addition to mean values and standard deviations. Diastolic and systolic diameters (DD/DS) in the left parasternal longitudinal and cross-sectional cuts gave similar results to those in the 4-chamber view from the apex: DD 2.7 +/- 0.4 (2.3-3.1) cm/m2, DS 1.8 +/- 0.4 (1.4-2.2) cm/m2, and DD 2.7 +/- 0.4 (2.3-3.1) cm/m2, DS 1.7 +/- 0.3 (1.4-2.0) cm/m2, respectively. Sizes of the right ventricle (1.8 +/- 0.4/1.4-2.2 cm/m2) and right atrium (2.4 +/- 0.5/1.9-2.9 cm/m2) could only be obtained in the 4-chamber view. Values for the left atrium (2.3 +/- 0.7/1.6-3.0 cm/m2) were obtained also in the left parasternal cross-section. Correcting for body surface, differences between males and females were reduced to the extent that there was no significant difference between them. These normal values make it possible to standardize the measurement of intracardiac dimensions by 2-D echocardiography and classify individual values.

Adolescent↗
PubMed1985

Combined medical and mechanical recanalization in acute myocardial infarction.

A technique of combined medical and mechanical recanalization was employed in 96 patients with acute transmural myocardial infarction. The mean time between onset of symptoms and admission to hospital was 170 +/- 65 min (X +/- SD). After 10 +/- 16 min, 250,000 U streptokinase was administered intravenously for 20 min. Intracoronary thrombolysis was commenced within 38 +/- 14 min. First coronary angiograms demonstrated reperfusion, an open vessel in 25/96 patients (26%). In 15/71 patients (21%) reperfusion occurred during thrombolysis therapy, before mechanical recanalization could be performed. Recanalization was achieved mechanically in 37/71 patients (52%) with occluded coronary vessels. In 8/71 patients (11%) mechanical recanalization failed but the vessel opened during thrombolysis. In 12/96 patients (12%), the coronary vessel remained occluded. Thus, reperfusion could be achieved in 88% of the patients. Reperfusion rate was 76% in the first 38 patients and 95% subsequently. After reperfusion, coronary thrombi were found in 25/96 patients (26%) but dissolved during thrombolysis in 16/25 patients (64%). Peripheral coronary embolism was observed in 3/25 patients (12%). For the whole group, reocclusion occurred in 8/84 patients (10%). By combined medical and mechanical recanalization, the recanalization rate could be increased with low reocclusion rate. Trends showed an improvement in regional and global left ventricular function in patients with anterior myocardial infarction.

Aged↗
PubMed1985

Hemichorea associated with varicella-zoster reinfection and endocarditis. A case report.

A 20-year-old woman developed transient right-sided hemichoreatic movements after household exposure to varicella-zoster. Some days before the appearance of involuntary movements a vesicular rash had occurred. About 6 months later an elevated IgG serum titer against varicella virus was found and two-dimensional echocardiography showed signs of an endocarditis. During the following 2 months the IgG value returned to within the normal range and the choreatic movements disappeared almost totally. The possibility is discussed that endocarditis had been caused and maintained by serum antibodies to varicella-zoster virus which cross-reacted with valvular tissue. Embolization to the region of the left striatum and/or postinfectious encephalitis in this region are assumed to be the most plausible causes of the transient hemichorea.

Adult↗
PubMed1985

Percutaneous transluminal coronary angioplasty (PTCA) following thrombolysis.

After successful intracoronary and intravenous thrombolysis in acute myocardial infarction in about 90% of all cases highgrade organic stenoses of the diseased vessels can be found. These obstructions may impede coronary blood flow and be the reason for recurrent angina in the rehabilitation phase. In a prospective, controlled, randomized study with 127 patients (pts) with acute myocardial infarction 64 pts were treated with streptokinase (group I) and 63 pts were treated with streptokinase and additional PTCA procedures (group II). The patients of both groups did not differ with respect to age, distribution of sex and diseased vessels, time between onset of symptoms and start of lysis or time to maximum of CPK-curve. In group I 59 out of 64 pts had recanalized vessels (92%), in group II 56 out of 63 pts (89%). In 55/56 pts PTCA was attempted (success rate 65%) with an artificial reocclusion in two pts (4%). After four weeks in group I 47 pts were controlled angiographically. The stenosis rate did not differ between the acute phase and the control study (78.6 +/- 11.8% vs. 78.0 +/- 15.2%). Five reocclusions had occurred. In group II the resting stenosis after thrombolysis (81.7 +/- 6.6%) was diminished by PTCA to 33.0 +/- 18.2%. In the control study the remaining stenosis was 31.9 +/- 24.4%. The difference between groups I and II at the four week control was highly significant (p less than 0.001). In group I there were ten deaths during the hospital phase, nine of them of cardiac origin. In group II nine pts died, three from shock lung and five from cardiac causes.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1985

[Detection of aneurysms of the atrial septum using transesophageal echocardiography].

In 7/340 patients (2.1%) examined by transesophageal echocardiography, aneurysms of the intraatrial septum were observed. In no patient were additional shunts present. In 3/7 patients mitral valve and in 2/7 patients tricuspidal valve prolapse was found. Intraatrial septum aneurysms seem to have a higher frequency than that indicated by transthoracical echocardiography. The incidence observed by transesophageal echocardiography corresponds to the incidence of pathological findings.

Adolescent↗
PubMed1985

[Brain abscess in a bidirectional atrial septal defect in adulthood].

An abscess of the brain is a serious complication in patients with congenital heart malformation. The great majority of cases are limited to cyanotic congenital heart disease and a peak in the age distribution can be seen in childhood. We report on a 40-year-old man with progressive right hemiparesis due to an abscess in the left basal ganglia. Clinical aspects and additional diagnostic assessment are described. By cardiologic examination including transoesophageal cross-sectional echocardiography a bidirectional sinus-venosus defect could be detected. This finding supported the diagnosis of a so-called 'paradoxical' brain abscess.

Adult↗
PubMed1984

Atrioventricular dissociation detected by suprasternal M-mode echocardiography: a clue to the diagnosis of ventricular tachycardia.

Twenty-two patients were studied by suprasternal M-mode echocardiography during ventricular tachycardia (VT). Adequate echocardiograms were obtained from 19 patients. Thirteen patients showed atrioventricular (AV) dissociation and 6 patients a ventriculoatrial contraction pattern according to the left atrial (LA) contraction obtained from the suprasternal notch. In 1 of these 6 patients, a 2:1 block retrograde was found by echocardiography. In another patient, an intermittent block occurred in the retrograde direction. In 4 patients, a constant relation between the QRS complex and LA contraction soon after the beginning of the QRS complex was seen, demonstrating a 1:1 ventriculoatrial conduction. According to the LA contraction obtained from the suprasternal echocardiogram, 13 patients showed AV dissociation and 6 patients a retrograde conduction to the LA. From the analysis of the 12-lead standard electrocardiogram obtained simultaneously during VT, AV dissociation could be recognized in only 3 patients. Thus, AV dissociation during VT is more easily diagnosed with suprasternal M-mode echocardiography than with the standard electrocardiogram.

Adult↗