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Biomedical subjects

W Klein

Publications and source records attributed to W Klein.

At least 37 records · Page 2Linked to original sources
PubMed2001

The CARE-HF study (CArdiac REsynchronisation in Heart Failure study): rationale, design and end-points.

BACKGROUND: Cardiac resynchronisation is a promising new intervention for patients with heart failure, left ventricular systolic dysfunction and ventricular dyssynchrony. OBJECTIVE: The CARE-HF trial is designed to evaluate the long-term effects of cardiac (atrio-bi-ventricular) resynchronisation on the mortality and morbidity of patients with heart failure due to left ventricular systolic dysfunction already receiving diuretics and optimal medical therapy with ACE inhibitors and beta-blockers (where indicated and tolerated). METHODS AND RESULTS: Approximately 800 patients will be randomised to device therapy or control and followed for a minimum of 18 months. A pragmatic study design has been chosen that does not attempt to conceal allocation from investigators or patients because it is impossible to guarantee maintenance of blinding for the duration of the study. The end-points committee will adjudicate events in a blinded fashion. Since cardiac resynchronisation may alter other aspects of the management of the patient, as would occur in clinical practice, the study should be considered a comparison of strategies rather than simply of a device. The primary end-point is all-cause mortality or unplanned cardiovascular hospitalisation. The study should complete recruitment during 2002 and report in 2004.

Adrenergic beta-Antagonists↗
PubMed2001

Interleukin-4 and interleukin-4 receptor gene polymorphisms in inflammatory bowel diseases.

Imbalances in the regulation of Th1 and Th2 lymphocytes are crucial in inflammatory bowel diseases. Interleukin-4 is secreted by Th2 lymphocytes and downregulates cytokine production from Th1 lymphocytes. Functionally relevant polymorphisms have been described in the interleukin-4 and the interleukin-4 receptor alpha genes. Association of inflammatory bowel diseases with these polymorphisms has been reported recently suggesting high transcription and enhanced signalling activity in Crohn's disease. Our study, comprising 211 patients with Crohn's disease, 147 patients with ulcerative colitis and 446 healthy controls revealed significant association of Crohn's disease with the -590 T allele of the interleukin-4 gene (P = 0.03). This allele entails reduced expression of IL-4. The reason for these contrasting findings may be discussed in the context of a putatively predisposing allele in linkage disequilibrium with the alleles of the interleukin-4 gene.

Alleles↗
PubMed2001

[Increased demand for psychosomatic consultation service (C-service) in a department of cardiology/pneumology due to psychometric screening].

The aim of the study was to test whether the routine use of the Hospital Anxiety and Depression Scale HADS changes the frequency and the duration of calling the psychosomatic C-service. 70% of all patients of the department of cardiology/pneumology were registered by the HADS. Psychometric screening raised the number of patients checked by the C-service (15.3 vs. 2.7% of all patients of the department; p < 0.01) and reduced the duration of the call for the C-service (2.7 vs. 6.4 days; p < 0.01) compared to conventional C-service. Elevated scores in HADS were found in 26% of the patients (21% depression, 12% anxiety).

Aged↗
PubMed2001

Sorption behavior of metolachlor, isoproturon, and terbuthylazine in soils.

The sorption-desorption of metolachlor [2-chloro-N-(ethyl-6-methyl phenyl)-N-(2-methoxy-1-methyl ethyl) acetamide], isoproturon [3-(4-isopropyl phenyl)-1,1-dimethyl urea] and terbuthylazine [N6-tert butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine] herbicides was studied in two German soils at 1:10 soil to water ratio by batch method. Equilibrium of herbicides between soil and water (0.01 M CaCl2) was attained in 2 h. Sorption data fitted very well to Freundlich equation, represented by very high correlation coefficient (r2 > 0.934). Comparison of Freundlich K values indicated that sorption of all the three herbicides was most pronounced in soil having higher organic carbon content. Koc values were as expected nearly identical for each herbicide in the two soils. The Freundlich constant (1/n) was about 1 for metolachlor and less than 1 for terbuthylazine and isoproturon indicating a L-type of sorption isotherms. Desorption of all the three herbicides showed hysteresis. Nearly equal amounts of metolachlor, isoproturon and terbuthylazine were desorbed from both soils. There was a good correlation between Koc and solubility.

Acetamides↗
PubMed2001

The polymorphism at position -174 of the IL-6 gene is not associated with inflammatory bowel disease.

OBJECTIVE: Inflammatory bowel diseases (IBD) are multifactorial disorders, characterized by failure to limit the inflammatory response to luminal antigens. Genetic factors play an important role in the pathogenesis, but little is known about the accountable genes. Increased secretion of pro-inflammatory cytokines appears crucial in the initiation of the inflammatory response. METHODS: To evaluate the role of the IL-6 gene in IBD, a functionally relevant polymorphism in the promoter region (G/C at position -174) has been genotyped in 169 patients with Crohn's disease (CD), 133 patients with ulcerative colitis (UC) and 440 healthy controls by using restriction fragment length polymorphism (RFLP) analysis. RESULTS: No significant differences were apparent in the allele, genotype and carrier frequencies between patients and controls. CONCLUSION: High secretion of IL-6 does not seem to play a major role in the genetic predisposition to IBD.

Alleles↗
PubMed2001

Role of the Bacillus subtilis fatty acid desaturase in membrane adaptation during cold shock.

In our attempt to understand the cold shock response of Bacillus subtilis, we report on the role of the B. subtilis fatty acid desaturase (FA-D) Des during membrane adaptation to low temperatures and demonstrate its importance during cold shock. A des null mutant was constructed and analysed in comparison with its parental strain. Growth studies and large-scale comparative fatty acid (FA) analysis revealed a severe cold-sensitive phenotype of the des deletion mutant during the absence of isoleucine and showed that four unsaturated fatty acid (UFA) species differing in length, branching pattern and position of the double bond are synthesized in B. subtilis JH642 but not in the des null mutant. Apart from the lack of UFA synthesis, the FA-D deletion strain showed a dramatically altered saturated fatty acid (SFA) profile at the onset of the stationary growth phase in the presence of exogenous isoleucine sources. Expression of des integrated in trans at the amyE locus of the des deletion strain not only cured the cold-sensitive phenotype observed for the des mutant but allowed much better growth than in strain JH642 after a shift from 37 degrees C to 15 degrees C. These results show that, during cold shock adaptation, des expression can completely replace the isoleucine-dependent, long-term, FA branching adaptation mechanism. We conclude that the crucial aspect in cold adaptation of the cytoplasmic membrane is not its specific molecular composition but rather its physical status in terms of its fluidity.

Adaptation, Physiological↗
PubMed2001

[Angiotensin I receptor blockers for heart failure].

Angiotensin conversion enzyme inhibitors (ACE-inhibitors) have long been the only possibility to influence the renin angiotensin system (RAS) and its often fatal influences in heart failure. In the last few years specific blockers of the angiotensin 1 receptor (AT I blockers) offered a new possibility for this therapeutic target. In contrast to ACE inhibitors AT I blockers are relatively new and, therefore, few data on heart failure are available. The first head-to-head studies that compared AT I blockers and ACE-inhibitors and their effect on mortality did not show a reduced mortality in the AT I blocker groups. Based on the available data AT I blockers should be used in heart failure patients who are intolerant of ACE-inhibitors.

Angiotensin Receptor Antagonists↗
PubMed2000

Molecular characterization of the transition state regulator AbrB from Bacillus stearothermophilus.

The Bacillus subtilis transition state regulator AbrB(su) is a DNA-binding protein that acts on several genes either as activator, repressor, or preventer. However, among genes under its control, neither common binding sites could be identified nor could the structural features of this broad and specific interaction be elucidated. Attempts to elucidate these interesting features by crystallizing AbrB(su) have failed so far. Therefore, to solve this problem, we focused in this work on identifying an AbrB(su) homologue from Bacillus stearothermophilus. Using a novel method, the entire abrB(st) gene of B. stearothermophilus was cloned and sequenced. The gene encodes a 95 amino acid protein that shows 77% identity and 85% similarity to the mesophilic B. subtilis protein. A calmodulin binding peptide-tagged fusion of the thermophilic gene was constructed for overexpression and efficient affinity column purification of the AbrB(st) protein. The purified protein showed, after removal of the tag, an oligomerization behavior through hexamer formation that is essential for its DNA binding activity.

Amino Acid Sequence↗
PubMed2000

Clusters and fluctuations at mean-field critical points and spinodals

We show that the structure of the fluctuations close to spinodals and mean-field critical points is qualitatively different from the structure close to non-mean-field critical points. This difference has important implications for many areas including the formation of glasses in supercooled liquids. In particular, the divergence of the measured static structure function in near-mean-field systems close to the glass transition is suppressed relative to the mean-field prediction in systems for which a spatial symmetry is broken.

Journal Article↗
PubMed2000

Segmental degradation of left ventricular wall motion after persistent coronary fistula in a posttransplantation patient: a case report and short review of literature.

A 50-year-old man received an orthotopic heart transplant because of severe coronary heart disease and congestive heart failure. Two years after the transplantation, a continuous murmur occurred at the left sternal edge after repeated endomyocardial biopsies. Echocardiography and coronary angiography revealed a dilated left anterior descending artery with a fistula to the right ventricle. The circumflex was large with an equally postero-lateral branch, and the right coronary artery was rather small with collaterals to the distal part of the left anterior descending branch. The patient had refused any intervention to close the fistula. The left ventricular levogram was normal. Two years later, in a follow-up angiogram, the left ventricular ejection fraction had decreased as a result of hypo- and akinesis of the apex and posterior wall. We suggest that this local wall motion disturbance derives from a steal phenomenon rather than being a sequela of rejection. The decrease in left ventricular ejection fraction was associated with shortness of breath upon moderate exercise. Standard heart failure medication relieved the patient's symptoms. The observation of local wall motion disturbances in this case, as well as conflicting views in the literature, raises the question whether postbiopsy coronary fistulas in transplant patients should be closed.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2000

The IL-10 gene is not involved in the predisposition to inflammatory bowel disease.

Although genetic predisposition for inflammatory bowel disease (IBD) is well established, little is known about the accountable genes. The pathogenesis of IBD is characterized by an imbalanced activation of Th1- and Th2-lymphocytes. IL-10 represents an anti-inflammatory cytokine which downregulates the production of Th1-derived cytokines. To evaluate the role of the IL-10 gene in IBD, two polymorphisms in the promoter region (G/A at position -1082 and C/A at position -592) were genotyped in 142 patients with Crohn's disease (CD), 104 patients with ulcerative colitis (UC), and 400 healthy controls. Significant differences were not apparent, neither in the allele frequencies of either polymorphism, nor in the haplotype frequencies. Screening of the coding region of the IL-10 gene by polymerase chain reaction--single strand conformation polymorphism (PCR-SSCP) analysis revealed a rare sequence variation in exon 1 leading to an amino acid exchange (G-->A; G15R) in two patients with CD and five healthy controls. Therefore, polymorphisms of the IL-10 gene are not demonstrably involved in the predisposition of IBD in our cohorts of patients.

Colitis, Ulcerative↗
PubMed2000

Reduction techniques in distal radius fractures.

External skeletal fixation is an important minimal invasive procedure in the management of fractures at the distal end of the radius. Attention to detail is important not only in the recognition of indications and function of the external fixator but also in its specific application. To improve anatomical restoration (e.g. palmar tilt) multi-planar ligamentotaxis is recommended. The demonstrated dynamic fixator is easy to apply and the double ball joint facilitates reduction after mounting by multi-planar ligamentotaxis. This transarticular unilateral external fixation system permits restoration of anatomy with the wrist in neutral or extension, thereby allowing full flexion of the metacarpophalangeal joints, with fingers and wrist extensor tendons relatively relaxed. Multi-planar ligamentotaxis, combined with a limited approach for supplementary procedures (fixation of articular fragments and/or bone grafting) and with early wrist motion, offers an encouraging treatment option in the management of unstable distal radial fractures by providing better anatomical restoration, especially of the palmar tilt and reduces the risk of wrist and finger stiffness.

Adult↗
PubMed2000

Results of transarticular fixator application in distal radius fractures.

From January 1989 until October 1993, 102 patients with 103 distal radius fractures were included in a prospective study with the Pennig wrist fixator (Orthofix, Srl, Italy). 90.5% of these patients were reviewed with a minimum follow-up of 12 months. Using the functional outcome score according to Gartland and Werley, we obtained 41% excellent, 46% good, 10% fair and 3% poor results. Additional procedures such as K-wires, bone grafting or radio-ulnar stabilizations were carried out in 61% of cases. The complications included five fixator displacements, four of which happened with the prototype used until the first half of 1990. Two major pin-track-infections required surgical intervention, three patients in the beginning of the series encountered irritations of the superficial radial nerve, one pin cut out of the second metacarpal bone and one patient sustained algodystrophy. The results show the significance of an anatomical reduction, the restoration of the radial length seems to be of special importance to obtain good functional outcome. This can not always be achieved with the fixator alone; often additional procedures are required in order to obtain an anatomical joint reconstruction. The advantage of this fixator lies in its lightweight and small-size design as well as in its easy application technique and the possibility to carry out the reduction after mounting the fixator with the double ball joint centered on the fracture level and the carpus.

Adolescent↗
PubMed2000

Comparison of wrist blood pressure measurement with conventional sphygmomanometry at a cardiology outpatient clinic.

OBJECTIVE: Oscillometric measurement of blood pressure at the wrist is becoming a widely used method for detection of hypertension and its control by treatment. The objective of the present study was to evaluate accuracy and suitability of wrist measurement in a clinical routine setting. PATIENTS AND METHODS: A series of 333 consecutive patients admitted to our cardiology outpatient clinic were included. Blood pressure was measured at both upper arms according to World Health Organization-International Society of Hypertension guidelines. Oscillometric measurement was performed at the contralateral wrist simultaneously. Blood pressure readings were taken by an oscillometric device applied at the wrist ('Klock'; Industrielle Entwicklung Medizintechnik, Stolberg, Germany) and a conventional mercury sphygmomanometer applied at the upper arm. RESULTS: Seventy-eight patients were excluded due to differences in blood pressure > 5 mmHg between both upper arms or due to 'error' messages of the wrist device. The data of the remaining 255 patients (149 males; mean age, 65 +/- 13 years; range, 18-95 years) are presented. Mean conventional blood pressure was significantly lower compared with the wrist device (137 +/- 20/80 +/- 11 mmHg versus 153 +/- 28/87 +/- 18 mmHg; P < 0.001 and P < 0.001). The mean difference was 16 +/- 25/6 +/- 17 mmHg. In clinical terms, differences in blood pressure exceeding +/-20/+/-10 mmHg reflecting classification of hypertension are considered important. Measurements of 101 (40%) patients were within these limits. Systolic readings of 110 (43%) and diastolic readings of 117 patients (46%) were beyond this scope. CONCLUSION: Due to low reliability of wrist blood pressure measurement, it cannot compete with the upper arm standard procedure. If ever, it should only be used if test readings in an individual comparing wrist and upper arm measurement show differences within a range of +/-20/+/-10 mmHg.

Adolescent↗
PubMed2000

Primary diffuse leptomeningeal gliomatosis: unusual MRI with non-enhancing nodular lesions on the cerebellar surface and spinal leptomeningeal enhancement.

A 28 year old man presented with a 1 month history of symptoms of intracranial hypertension. Examination showed bilateral papilloedema and meningeal signs. Magnetic resonance imaging showed nodular lesions on the cerebellar and pontine surface and thickening of the thoracic spinal leptomeninges. Throughout the course of the disease, contrast enhancement was detected in the spinal leptomeninges but not intracranially. Primary diffuse leptomeningeal gliomatosis (PDLG) was diagnosed by biopsy and later confirmed on necropsy. The present case is remarkable for the nodular superficial cerebellar lesions and the absence of intracranial contrast enhancement of the leptomeninges.

Adult↗