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C Scharf

Publications and source records attributed to C Scharf.

At least 19 recordsLinked to original sources
PubMed2005

[Atrial flutter and fibrillation].

This article summarizes current understandings and therapies for both arrhythmias. Atrial flutter is most often arising from a macroreentry circuit in the right atrium or around scar tissue in case or previous cardiothoracic surgery. As a macroreentrant tachycardia it is regular and can lead to higher heart rates, especially if occurring with 1:1 conduction. In contrast atrial fibrillation, especially when occurring paroxysmal at the beginning, is arising from triggers within the pulmonary veins. Ablation strategies to electrically isolate those triggers have a treatment success rate of 80%, which is much more than can be achieved with antiarrhythmic medication (success rates 30-50%). Emergency treatment of both arrhythmias include cardioversion and pacemaker implantation with AV node ablation if necessary.

Adrenergic alpha-Antagonists↗
PubMed2003

[Stress, depression and cardiac arrhythmias].

A relationship between behavioural factors and cardiac arrhythmogenesis in humans has been described. Three sets of conditions contribute to the occurrence of arrhythmias: myocardial electrical instability, most often due to coronary artery disease; an acute triggering event, frequently related to mental stress; and a chronic, pervasive, and intense psychological state, often including depression and hopelessness. The autonomic nervous system plays an important role in the occurrence of cardiac arrhythmias and it is well documented that mood alterations as mental stress and depression influence cardiac autonomic balance. There is an increasing body of evidence that patients with the greatest changes in cardiac neural regulation with decreased parasympathetic tone coupled with increased sympathetic activity are at the greatest risk for developing fatal ventricular arrhythmias. These patients have a reduced heart rate variability, increased QT-dispersion and a decreased baroreceptor sensitivity. The influence of stress and depression on the autonomic nervous system and the impact on the occurrence of both atrial and ventricular arrhythmias is being discussed.

Arousal↗
PubMed2002

[Cholestatic jaundice and pruritus].

The 38 year old male patient was admitted to our clinic with jaundice and invalidating pruritus of unknown origin. The primary evaluation made by the practitioner of the patient and the initial examinations performed in the clinic revealed no diagnosis. In particular, an infectious liver disease could be excluded. Reevaluation of anamnestic data revealed then the in-take of Dianabol, an often used anabolic steroid as the most possible reason for the cholestatic hepatopathy.

Adult↗
PubMed2001

[Ventricular tachycardia].

In patients with ventricular tachycardias, various structural and functional conditions can be influenced by certain triggers, initiating the mechanism of the arrhythmia. Thorough understanding of these different factors is paramount for the appropriate choice of treatment. Several options are available for the management of ventricular tachycardias: antiarrhythmic drugs, ICD implantation and catheter ablation or a combination of the above. The prognosis of an individual patient is determined by the underlying disease, the mechanism of tachycardia and the selected therapy. The complexity of several conditions requires a specialized diagnostic approach and tailored medical management. Therefore the patients with the following diagnoses should be referred to a specialized electrophysiology center: survivors of sudden cardiac death old infarct scar, reduced ejection fraction and complex ectopy Cardiomyopathy with syncope or ventricular tachycardias Long QT-Syndrome Brugada Syndrome Right Ventricular Dysplasia recurrent syncopes of unclear etiology.

Anti-Arrhythmia Agents↗
PubMed2001

A comprehensive two-dimensional map of cytosolic proteins of Bacillus subtilis.

Proteomics relying on two-dimensional (2-D) gel electrophoresis of proteins followed by spot identification with mass spectrometry is an excellent experimental tool for physiological studies opening a new perspective for understanding overall cell physiology. This is the intriguing outcome of a method introduced by Klose and O'Farrell independently 25 years ago. Physiological proteomics requires a 2-D reference map on which most of the main proteins were identified. In this paper, we present such a reference map with more than 300 entries for Bacillus subtilis proteins with an isoelectric point (pI) between 4 and 7. The most abundant proteins of exponentially growing cells were compiled and shown to perform mainly housekeeping functions in glycolysis, tricarboxylic acid cycle (TCC), amino acid biosynthesis and translation as well as protein quality control. Furthermore, putative post-translational modifications were shown at a large scale, with 47 proteins in total forming more than one spot. In a few selected cases evidence for phosphorylation of these proteins is presented. The proteome analysis in the standard pI range was complemented by either stretching the most crowded regions in a narrow pH gradient 4.5-5.5, or by adding other fractions of the total B. subtilis proteome such as alkaline proteins as well as extracellular proteins. A big challenge for future studies is to provide an experimental protocol covering the fraction of intrinsic membrane proteins that almost totally escaped detection by the experimental procedure used in this study.

Bacillus subtilis↗
PubMed2001

Sudden cardiac death after coronary artery bypass grafting is not predicted by signal-averaged ECG.

BACKGROUND: Sudden cardiac death (SCD) is a major cause of death despite successful revascularization in patients with coronary artery disease. The signal-averaged ECG (SAECG) is a sensitive predictor of SCD and could be used in the screening strategy to select patients for prophylactic cardioverter implantation. METHODS: The SAECG was recorded in 561 patients (mean age: 60 +/- 8.8 years) within 10 days of coronary artery bypass grafting. Signal-averaged ECG was performed with a bandpass filtering of 40 to 250 Hz for more than 250 beats until a noise level of 0.6 microV was achieved. All patients were followed for 5.5 +/- 1.2 years after the procedure. RESULTS: Preoperative angiographic ejection fraction was at least 60% in 393 patients (72%), 40% to 60% in 126 patients (23%), and 40% or less in 28 patients (5%). There were 34 deaths, 10 of which were SCD. Late potentials were found in a total of 150 patients (27%) and were equally frequent preoperatively and postoperatively and among patients with (30%) and without (27%) SCD. The only predictors for overall mortality were age and a reduced ejection fraction. CONCLUSIONS: Signal-averaged ECG did not predict prognosis in low-risk patients undergoing coronary artery bypass grafting.

Coronary Artery Bypass↗
PubMed2001

Tumour-related enzyme alterations in the clear cell type of human renal cell carcinoma identified by two-dimensional gel electrophoresis.

To identify tumour-related enzyme alterations we have used 2D-gels to analyse the proteome from dissected malignant and benign kidney areas from patients with clear-cell-type renal carcinoma. The expression of 12 proteins was diminished in tumour. Four proteins were characterized by mass spectrometry and were identified as enoyl-CoA hydratase, alpha-glycerol-3-phosphate dehydrogenase, aldehyde dehydrogenase 1 and aminoacylase-I.

Aldehyde Dehydrogenase↗
PubMed2000

Monitoring of genes that respond to overproduction of an insoluble recombinant protein in Escherichia coli glucose-limited fed-batch fermentations.

The cellular response of Escherichia coli to overproduction of the insoluble heterologous protein alpha-glucosidase of Saccharomyces cerevisiae during a glucose-limited fed-batch fermentation was analyzed on the transcriptional and the translational levels. After the induction of the tac-regulated overexpression of the recombinant model protein, a significant but transient increase of the mRNA levels of the heat shock genes lon and dnaK could be observed. The mRNA level of the gene coding for the inclusion body-associated protein IbpB showed the strongest increase and remained at a clearly higher level until the end of the fermentation. By contrast, the mRNA levels of htrA and ppiB were decreased after induction of the alpha-glucosidase overexpression. Analysis of the soluble cytoplasmic protein fraction 3 h after induction revealed increased levels of the chaperones GroEL, DnaK, and Tig and a decrease in the protein levels of the two ribosomal proteins S6 and L9, the peptidylprolyl-cis-trans-isomerase PpiB, and the sigma(38)-dependent protein Dps. Analysis of the aggregated protein fraction revealed a remarkably inhomogeneous composition of the alpha-glucosidase inclusion bodies. N-terminal sequencing and MALDI-TOF mass spectrometry identification showed that most of these spots are fragments of the heterologous alpha-glucosidase. Host stress proteins, like DnaK, GroEL, IbpA, IbpB, and OmpT, have been found to be associated with the alpha-glucosidase protein aggregates.

Biotechnology↗
PubMed2000

Evidence for X-Ray Emission from a Large-Scale Filament of Galaxies?

Cosmological simulations predict that a large fraction of the baryonic mass of the universe exists as 105-107 K diffuse, X-ray-emitting gas, tracing low-density filament and sheetlike structures exterior to massive clusters of galaxies. If present, this gas helps reconcile the current shortfall in observed baryon counts relative to the predictions of the standard big bang model. We present here the discovery and analysis of a 5 sigma significance half-degree filamentary structure, which is present in both the I-band galaxy surface density and the unresolved X-ray emission in a deep ROSAT PSPC field. The estimated diffuse X-ray emission component of this structure has a surface brightness of approximately 1.6x10-16 ergs s-1 cm-2 arcmin-2 (0.5-2 keV), comparable to the predictions for intercluster gas, and may represent a direct detection of this currently unconfirmed baryonic component.

Journal Article↗
PubMed2000

Alkaline proteins of Bacillus subtilis: first steps towards a two-dimensional alkaline master gel.

The genomic sequence of Bacillus subtilis, which is the best studied Gram-positive bacterium, enabled us to obtain a theoretical two-dimensional (2-D) map, demonstrating that about one-third of this proteome has a theoretical alkaline isoelectric point (pI). This represents an important part of the entire proteome, which is not detectable in conventional 2-D gels (pH range 4-7). Sequence analysis revealed that 91% of the ribosomal proteins and a high amount of theoretical membrane proteins should be localized in the alkaline pH range requiring different protein extraction procedures. In order to find the pH range which gives the best resolution results for the alkaline proteins of B. subtilis, immobilized pH gradients (IPGs) with different pH ranges (pH 6-10, 6-11, 4-12, 9-12, and 3-10) were tested and optimized for IPG 4-12. Here we present a version of a first alkaline master 2-D gel for B. subtilis, which is a further complement of the already existing master gel (pH 4-7) in the Sub2D database. Almost 150 spots could be detected and 41 proteins have already been identified.

Alkalies↗
PubMed2000

[Heart transplantation: indications and results].

Heart transplantation has been established as therapy in patients with terminal heart failure who remain severely symptomatic (NYHA III-IV) despite optimal drug therapy and surgical interventions other than transplantation. In addition to symptoms, various objective criteria are used to determine the patients most suitable for transplantation. Of these, peak oxygen consumption below 12-14 ml/kg/min, no irreversibly elevated pulmonary resistance, and no major concomitant disease are most important. However, conventional therapy of advanced heart failure has considerably improved over the last decade. Thus, heart transplantation may be avoided or at least postponed in many patients. Nevertheless, continuous treatment at a heart failure/heart transplantation clinic in collaboration with the general practitioner is essential in these patients. This may allow to closely monitor these severely ill patients and to select the optimal point of time for transplantation. Prognosis after heart transplantation is relatively good with a 10-year survival of 63%. However, graft coronary artery disease and lymphomas are still unresolved problems which limit the success of heart transplantation. Competent clinical monitoring, aggressive therapy of conventional risk factors and good co-operation of patients and doctors are the basis for a successful outcome.

Graft vs Host Disease↗
PubMed2000

Phosphate starvation-inducible proteins of Bacillus subtilis: proteomics and transcriptional analysis.

The phosphate starvation response in Bacillus subtilis was analyzed using two-dimensional (2D) polyacrylamide gel electrophoresis of cell extracts and supernatants from phosphate-starved cells. Most of the phosphate starvation-induced proteins are under the control of sigma(B), the activity of which is increased by energy depletion. In order to define the proteins belonging to the Pho regulon, which is regulated by the two-component regulatory proteins PhoP and PhoR, the 2D protein pattern of the wild type was compared with those of a sigB mutant and a phoR mutant. By matrix-assisted laser desorption ionization-time of flight mass spectrometry, two alkaline phosphatases (APases) (PhoA and PhoB), an APase-alkaline phosphodiesterase (PhoD), a glycerophosphoryl diester phosphodiesterase (GlpQ), and the lipoprotein YdhF were identified as very strongly induced PhoPR-dependent proteins secreted into the extracellular medium. In the cytoplasmic fraction, PstB1, PstB2, and TuaD were identified as already known PhoPR-dependent proteins, in addition to PhoB, PhoD, and the previously described PstS. Transcriptional studies of glpQ and ydhF confirmed the strong PhoPR dependence. Northern hybridization and primer extension experiments showed that glpQ is transcribed monocistronically from a sigma(A) promoter which is overlapped by four putative TT(A/T)ACA-like PhoP binding sites. Furthermore, ydhF might be cotranscribed with phoB initiating from the phoB promoter. Only a small group of proteins remained phosphate starvation inducible in both phoR and sigB mutant and did not form a unique regulation group. Among these, YfhM and YjbC were controlled by sigma(B)-dependent and unknown PhoPR-independent mechanisms. Furthermore, YtxH and YvyD seemed to be induced after phosphate starvation in the wild type in a sigma(B)-dependent manner and in the sigB mutant probably via sigma(H). YxiE was induced by phosphate starvation independently of sigma(B) and PhoPR.

Alkaline Phosphatase↗
PubMed2000

Characterization of the sigma(B) regulon in Staphylococcus aureus.

The sigma(B)-dependent stress regulon in gram-positive bacteria might fulfill a physiological role in stress response and virulence similar to that of the sigma(S) regulon in Escherichia coli and other gram-negative bacteria. In order to obtain evidence for the function of the sigma(B) regulon of Staphylococcus aureus, especially in virulence control, sigma(B)-dependent stress genes were identified. The two-dimensional protein pattern of wild-type cells of S. aureus COL was compared with that of an isogenic sigB mutant. By this approach, we found that the synthesis of about 27 cytoplasmic proteins seemed to be under the positive control of sigma(B). N-terminal sequencing of 18 proteins allowed the identification of their genes on the almost finished genome sequence of S. aureus COL and the analysis of the promoter structure. Transcriptional analyses of 11 of these genes confirmed their sigma(B) dependency, and moreover, about 7 additional sigma(B)-dependent genes were found which are cotranscribed with the newly detected genes, forming operons. Altogether, we identified 23 sigma(B)-dependent genes and their corresponding proteins. Among them are proteins probably involved in the generation of NADH or in membrane transport mechanisms. Furthermore, at least one clpC-homologous gene was localized on the S. aureus sequence solely transcribed by sigma(B). In contrast, a second clpC-homologous gene in S. aureus forming an operon with ctsR, yacH, and yacI was sigma(B) independently expressed.

Bacterial Proteins↗
PubMed1999

Dual channel imaging of two-dimensional electropherograms in Bacillus subtilis.

The allocation of proteins to stimulons and regulons is an essential step towards the understanding of the global regulation of the expression of entire genomes. The computer-aided evaluation and matching of two-dimensional protein gels loaded with radioactively labeled proteins from exponentially growing or stressed cells is a useful but time-consuming procedure for the description of stimulons and regulons. This paper describes the dual-channel image analysis that offers the opportunity to visualize the content and synthesis rate of a whole set of bacterial proteins on a single electropherogram. By pulse-labeling with L-[35S]methionine, the protein synthesis pattern (red color) can be directly compared with the protein level pattern (green color). Because matching of other gels can be avoided, this new technique is useful for the rapid search for proteins that belong to different stimulons or regulons. This approach was tested for the identification of proteins of heat stress or oxidative stress stimulons. Proteins that were induced by heat or oxidative stress colored red while proteins whose synthesis was switched off by the stress factor colored green. Proteins that were continuously synthesized before and after the imposition of stress retained their yellow color. The advantages and possible pitfalls of the technique are discussed.

Bacillus subtilis↗