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D Pfeiffer

Publications and source records attributed to D Pfeiffer.

At least 19 recordsLinked to original sources
PubMed2007

[123I-Metaiodobenzylguanidine- (MIBG-) scintigraphy: paradoxical positivity in an oncocytic adrenocortical carcinoma].

(123)I-metaiodobenzylguanidine (MIBG), a radio-labeled catecholamine analogue, is used for the imaging of pheochromocytoma based on the selective uptake of MIBG by chromaffin tissues. MIBG scintigraphy displays high sensitivity (90%) and specificity (close to 100%). In contrast, the false-positive uptake of MIBG by adrenal cortical carcinoma is rare. Here, we report a metastatic oncocytic adrenal cortical carcinoma with MIBG uptake used for therapeutic purposes.

3-Iodobenzylguanidine↗
PubMed2006

[Modern pacing therapy].

Since pacemakers first have been implanted in 1958 considerable technical progress has been achieved. The devices are more efficient today, have complex diagnostic functions, memory capacity and it is even possible to get telemetric software updates. Automatic mode switch due to changing heart rhythm, adaptation of AV-delay, auto sensing and auto stimulation threshold are available and facilitate pacemaker follow up. Because of continuously progress in pacing therapy guidelines have to be updated very often. The newest German and international guidelines for pacing therapy have been published in 2005 by Deutsche Gesellschaft für Kardiologie/ Herz- und Kreislaufforschung (DGK). Indications for pacing therapy increases continuously. Not only bradycardia, but also heart failure, prophylactic pacing to prevent and to terminate tachyarrhythmias are modern fields of pacing therapy.

Bradycardia↗
PubMed2006

A Doppler-based study on the prevalence of varicocele in German children and adolescents.

The prevalence of varicocele was estimated among pupils of forms 4 and 8 in the city of Hamburg and the severity of the associated venous reflux was analysed. In the school year of 1998/99, a genital examination was performed on 2756 children (median age 10.2 years) and 2008 adolescents (14.6 years). The varicocele degree was determined according to the WHO. Venous reflux was proven by CW-Doppler sonography, distinguishing between Valsalva-induced reflux (VR) and continuous reflux (CR). As a result, varicoceles were detected in 18.0% of the children (1.2% bilaterally) and 42.7% of the adolescents (7.2%). High-graded forms (palpable/visible) occurred with increasing rate (from 7% to 22.9%) on the left side. Subtle forms (subclinical/during Valsalva) counted for >90% of all right-sided findings, whilst an age-related shift towards higher degrees was noted left-sided. VR occurred bilaterally, CR was almost only established left-sided. VR was mainly associated with subtle varicoceles, CR was predominantly found in the high-graded forms. These results suggest that even in children varicoceles are not a rare phenomenon. However, adolescence is the main period of manifestation. A major venous malfunction is already evident in maturing boys, which seems to be associated with the formation of high-graded varicoceles.

Adolescent↗
PubMed2006

Epidemiology and ecology of highly pathogenic avian influenza with particular emphasis on South East Asia.

Highly pathogenic avian influenza (HPAI) has been recognised as a serious viral disease of poultry since 1878. The number of recorded outbreaks of HPAI has increased globally in the past 10 years culminating in 2004 with the unprecedented outbreaks of H5N1 HPAI involving at least nine countries in East and South-East Asia. Apart from the geographical extent of these outbreaks and apparent rapid spread, this epidemic has a number of unique features, among which is the role that asymptomatic domestic waterfowl and more particularly free-ranging ducks play in the transmission of highly pathogenic H5N1. Field epidemiological studies have been conducted by the Food and Agriculture Organization and several collaborative centres to explore the factors that could have led to a change from infection to the emergence of widespread disease in 2003-2004 and 2005. Domestic waterfowl, specific farming practices and agro-ecological environments have been identified to play a key role in the occurrence, maintenance and spread of HPAI. Although there are some questions that remain unanswered regarding the origins of the 2004 outbreaks, the current understanding of the ecology and epidemiology of the disease should now lead to the development of adapted targeted surveillance studies and control strategies.

Agriculture↗
PubMed2005

Subchronic alpha- and beta-adrenergic regulation of cardiac gap junction protein expression.

Gap junction channels are essential for intercellular electrical communication in the heart. The most important cardiac gap junction proteins are connexin43 (predominantly) (Cx43), connexin40 (Cx40), and in early developmental stages connexin45. Since catecholamines play an important role in cardiac (patho)physiology, we wanted to elucidate whether catecholamines may affect expression of Cx43 and Cx40. Cultured neonatal rat cardiomyocytes were exposed for 24 h to increasing concentrations of noradrenaline (1-10000 nM) (physiological agonist at alpha and beta-adrenoceptors), resulting in significantly increased Cx43-expression, while Cx40 was unaffected. In further experiments cells were incubated with either phenylephrine (alpha-adrenergic agonist) or isoproterenol (beta-adrenergic agonist) (0.1-1000 nM) for 24 h. Both catecholamines lead to a concentration-dependent increase in Cx43 protein and mRNA expression (EC50: 10-20 nM). Inhibition experiments showed that the phenylephrine effect was transduced via PKC, while the isoproterenol effect was mediated by PKA. Dual whole-cell voltage clamp demonstrated that increased Cx43-expression was accompanied by significant increases in gap junction current. In additional in vivo experiments, adult rats were subjected to 24-h infusion of isoproterenol or phenylephrine showing again significant increase in Cx43 but not Cx40. Adrenergic stimulation of cardiomyocytes can enhance Cx43 expression thereby increasing cellular coupling, indicating a possible role for catecholamines in the regulation of cardiac gap junction expression in cardiac disease.

Adrenergic alpha-Agonists↗
PubMed2005

[Resuscitation by laypersons: lack of knowledge of first-aid measures in Germany].

BACKGROUND AND OBJECTIVE: Sudden cardiac death is a leading cause of death. In Germany, only 10% of patients will survive reanimation. The prognosis is mainly determined by the first-aid skills of accidental witnesses. METHODS: The reaction of 1007 German-speaking adults (462 males, 545 females, median age 39 years) was investigated in an emergency scenario with symptoms of sudden cardiac death in an acquaintance. Afterwards a self-assessment of their first-aid skills, such as cardiac compression and mouth-to-mouth ventilation was made. RESULTS: 94% of the interviewees would call professional aid at once. Diagnostic skills, as searching for pulse or checking for breath would be done by 26 and 21%, respectively. The most frequently mentioned therapeutic skill was positioning the victim in stable lateral position (37%), but very less frequently cardiac compression (6%) and mouth-to-mouth resuscitation (10%). When asked, 51 (81%) of those interviewed regarded their skills in cardiac compression and mouth-to-mouth resuscitation as adequate. To some extent there were differences in favor of young people and those from East Germany. CONCLUSION: These representative data suggest that (a) ABC-like first-aid rules are largely unknown among the population; (b) the value of a stable lateral position is overestimated and (c) first-aid skills of elderly persons are worst. A significant improvement of first-aid skills of the German population is mandatory in order to improve in future the outcome of sudden cardiac death.

Adolescent↗
PubMed2005

[Rare cause of pectangina after coronary artery surgery].

The coronary subclavian-steal-syndrome is a rare cause for angina pectoris following A. mammaria interna bypass operation. A 72-year-old male patient presented with vertigo and angina pectoris. A three vessel coronary artery disease was known and coronary artery surgery with three aortocoronary bypasses had been performed a year prior to presentation. A difference in peripheral arterial pressure between the right (150/80 mmHg) and the left (125/75 mmHg) arm was noted at physical examination. Color Doppler sonography of the left vertebral arteria exhibited a retrograde flow suggesting a coronary subclavian-steal-syndrome. Angiography revealed a significant stenosis of the left arteria subclavia. The stenosis was successfully treated with percutaneous transluminal angioplasty and stent implantation.

Aged↗
PubMed2005

[Echocardiographic functional analysis of patients with rheumatoid arthritis and collagen diseases].

Cardiac manifestations were observed in patients with rheumatoid arthritis and other collagenoses. Echocardiography is a method of choice to detect pathologies in morphology and function of the heart. Pathophysiologically inflammatory alterations of the endo- as well as perimyocardium can be explained in these patients. In addition, in patients with collagenoses, the coagulation system is activated and the reactivity of the endothelium is reduced. Thus, thrombus formation at the heart valves with consecutive stenosis and/or regurgitations as well as ischemia-induced regional wall motion defects due to reduced vasodilator response of the coronary arteries can be expected. In the literature in patients with rheumatoid arthritis and other collagenoses, pericardial effusion and pulmonary hypertension are most frequently described. The echocardiographic analysis, however, is more complex due to the variability of the patient cohort. Quantification of valve defects and the analysis of wall motion and perfusion at rest and during stress is necessary to detect early changes of the diseases. The prerequisites for successful diagnostic echocardiography in these patients are the knowledge of modern echocardiographic techniques like tissue Doppler and contrast echocardiography and clinical experience with patients with rheumatoid arthritis and other collagenoses. The standardization of the echocardiographic diagnostic procedure becomes more and more important for reproducibility and comparability of the results.

Arthritis, Rheumatoid↗
PubMed2004

Estimation of vasodilator response by analysis of Doppler intensity kinetics with myocardial contrast echocardiography using an intravenous standardized bolus administration.

HYPOTHESIS: Myocardial perfusion can be analyzed by the first pass of Doppler intensity (DI) signals in the myocardium by myocardial contrast echocardiography with triggered power Doppler harmonic imaging (PDHI). METHODS AND RESULTS: DI versus time plots during 1:1 triggering was acquired during a mechanically standardized intravenous bolus application of Levovist (400 mg ml(-1); 3 ml min(-1)) at rest and during vasodilator stress with dipyridamole. Data were analyzed in 21 patients (pts) with normal coronary arteries and in 6 pts with left anterior descending artery (LAD) stenosis. Transthoracic distal LAD-flow velocities could be determined in 7 normal pts. At stress the DI wash-in rate and the DI plateau increased (3.14+/-0.3 versus 5.06+/-0.4 DI s(-1); 24.6+/-2.5 versus 30.8+/-1.8 DI, respectively). To analyze the effect of heart rate on the DI versus time plots investigations were performed in 7 additional controls at rest and during rapid pacing. Heart rates below 100 bpm did not disturb the DI kinetics at 1:1 triggering. CONCLUSIONS: Myocardial perfusion can be assessed by the analysis of the first pass DI kinetics using Levovist. The estimation of vasodilator response by PDHI seems to be an alternative to the determination of coronary flow reserve.

Aged↗
PubMed2004

A comparison of methods for measuring serum and urinary markers of bone metabolism in cats.

Biochemical markers of bone cell activity have recently been shown to be useful for monitoring skeletal health in domestic animals, including dogs and horses. The aim of this study was to evaluate a number of biochemical assays, originally developed for use in humans, for their ability to measure indicators of bone cell activity in serum and urine of normal cats over a range of ages. Bone alkaline phosphatase (BAP), a marker of bone formation, was measured in serum using wheatgerm lectin precipitation (WGL) and by ELISA. The curve derived from serial dilution of feline serum was parallel with the ELISA standard curve, indicating species cross-reactivity, and there was a significant relationship between assays (rs = 0.97, P < 0.001). Deoxypyridinoline (DPD), a marker of bone resorption, was measured in its total form in urine by HPLC and ELISA, and in its free form in serum and urine by ELISA. The dilution curve for free DPD in urine showed parallelism with the assay standard curve; however, the curves for total DPD in urine and serum did not. A significant relationship was established between total urinary DPD (HPLC) with total serum DPD (rs = 0.69, P < 0.001), and with free urinary DPD (rs = 0.95, P < 0.001) concentrations. Carboxy-terminal telopeptide of type I collagen (CTX) concentration, another marker of bone resorption, was measured in serum and urine by ELISA, and there was a significant relationship between assays (rs = 0.82, P < 0.001). CTX could not be measured reliably using an auto-analysis method. A significant relationship was established between total urinary DPD (HPLC) with serum CTX (rs = 0.59, P < 0.05), and urinary CTX (rs = 0.65, P < 0.001) concentrations. BAP (ELISA and WGL), total urinary DPD (HPLC), urinary CTX (ELISA), and serum CTX (ELISA) concentrations were significantly inversely correlated with age (rs = -0.66, -0.88, -0.61, -0.70, and -0.51, P < 0.05 respectively). Cats under two years of age had significantly higher BAP, total urinary DPD (HPLC), and urinary CTX concentrations compared to older cats. In conclusion, this study has shown that a number of commercially available assays provide reliable methods for non-invasively monitoring bone cell activity in cats and has shown that bone turnover decreases within the first two years of life, until complete skeletal maturity is attained. Future studies can now be directed at evaluating the potential clinical application of these methods.

Alanine Transaminase↗
PubMed2004

Myocardial contrast echocardiography demonstrates myocardial hypoperfusion in the LAD territory in patients with acute chest pain at rest--a prospective study using power Doppler harmonic imaging with intravenous bolus application.

AIMS: Using a previously published algorithm we hypothesize that myocardial contrast echocardiography (MCE) with power Doppler harmonic imaging (PDHI) is able to detect regional hypoperfusion within the territory of the left anterior descending artery (LAD) using intravenous (i.v.) injection of contrast in patients (pts) with coronary syndrome at rest. METHODS AND RESULTS: Forty-seven consecutive patients (pts) were prospectively evaluated using a standardized i.v. bolus application of OPTISON. MCE data were acquired within 2 h before angiography. Cut-off Doppler intensity (DI)-values determined in the apical, mid, and basal septum were distinguished between normal and hypoperfused myocardium (e.g. 23.5 and 22.5 dB for maximum DI of the apical or mid-septum triggering on every third heart cycle). Seventeen of 42 pts were classified as normal and the remaining 25 pts as pathologic (10 of these 25 pts had elevated troponines). Angiography detected open vessels or TIMI-III-flow in 15 pts of the normal MCE group, significant stenosis (>70%) or reduced TIMI-flow in 22 pts of the pathologic MCE group. The highest sensitivities (83-92%) were found in the apical septum. CONCLUSION: Assessment of the myocardial perfusion deficits in the LAD territory of pts with acute coronary syndrome is feasible with MCE with PDHI using an i.v. bolus protocol.

Acute Disease↗
PubMed2003

Chronic regulation of the expression of the gap junction protein connexin 43 in transfected HeLa cells.

Gap junction channels are essential for intercellular communication. Among the most abundant gap junction channel proteins is connexin 43 (Cx43). The goal of our study was to find out, whether Cx43 content may be regulated via adenylyl cyclase (AC)/cAMP/protein kinase A (PKA), protein kinase C (PKC) pathways or by a tyrosine kinase coupled pathway, i.e. TNF alpha-receptor dependent pathway. Therefore, we used HeLa cells transfected with Cx43 and exposed these cells for 24 h to either db-cAMP (10(-4)M), forskolin (10(-5)M), the phorbolester phorbol-12,13-didecanoate PDD (10(-7)M) (or its inactive form 4 alpha-PDD), TNF alpha (10 U/ml) with or without additional treatment with the MAP kinase inhibitors SB203580 (10(-5) M, p38 MAP-kinase inhibitor) or the MEK1-inhibitor PD98059 (10(-5)M). Cx43 content was analysed using Western blot analysis. All results were confirmed by a second series of identical experiments using Cx43 immunohistochemistry. We found significantly enhanced Cx43 content in cells treated with db-cAMP, forskolin, PDD or TNF alpha (p<0.05), while 4 alpha-PDD or the solvent DMSO exerted no effect. These increases in Cx43 content could be completely suppressed by SB203580 (p<0.05) but not by PD98059. In absence of a stimulating drug, these inhibitors (SB203580 or PD98059) did not affect Cx43 content. Additional PCR experiments revealed increases in Cx43-mRNA under the influence of db-cAMP, forskolin, PDD or TNFalpha (p<0.05), which all could be completely suppressed by SB203580. From these results we conclude that 1.Cx43 content can be regulated via AC/cAMP/PKA, PKC and TNF alpha-receptor-dependent pathways 2. Activation of p38 MAP kinase is a common pathway for regulation of Cx43 content in HeLa cells

Adenylyl Cyclases↗
PubMed2003

[Antegrade sclerotherapy for varicocele testis--possible and avoidable complications].

Antegrade sclerotherapy is an established procedure for the treatment of varicocele. To avoid complications during the dissection of the pampiniform plexus, detailed knowledge of the angioarchitecture of the spermatic cord is recommended. One group of plexus veins is situated ventrolaterally and is surrounded by a yellowish fat which serves as a landmark. This vein group should be chosen for preparation. Phlebography of the internal testicular vein is mandatory. If arteries or major pelvic veins become visible while applying contrast media, sclerotherapy should not be performed. Paravasation of sclerosing agent has to be recognized and treated immediately to prevent deleterious effects.

Catheterization↗
PubMed2003

Myocardial contrast echocardiography for assessment of myocardial perfusion at rest in a patient with left main coronary artery stenosis.

The present case will focus on the potential of hypoperfusion detection with myocardial contrast echocardiography (MCE) using power Doppler harmonic imaging (PDHI). PDHI is normally performed in a triggered mode. Microbubbles were destroyed by the ultrasound energy in the myocardium, and myocardium has to be refilled with microbubbles within the time interval between the ultrasound pulses to obtain repetitive information about perfusion. Using the contrast agent Levovist, however, real-time PDHI also results in myocardial opacification presumably due to perfusion signals of the arteriolar microbubble passage. A 45-year-old woman with typical stress-induced angina was admitted to our department for cardiac catheterization. Prior to the angiography a conventional echocardiogram showed normal left ventricular function. Tissue Doppler, however, demonstrated postsystolic longitudinal shortening of the septal, anterior, and lateral wall regions. Myocardial contrast echocardiography with triggered PDHI showed complete opacification of the myocardium at rest. Using real-time PDHI with Levovist, the septum could not be opacified. The consecutive angiography documented a severe unprotected main coronary artery stenosis. After angioplasty and stent implantation, MCE measurements were repeated. Repetitive intravenous bolus injections of Optison during triggered PDHI showed no differences to the investigation prior to the angioplasty. Using real-time PDHI with Levovist, however, there was a marked difference in comparison to the pre-interventional analysis. A complete opacification of the apical septum was observed. The present case suggests that different MCE techniques can analyze different compartments of the myocardial vasculature in clinical practice. This methodological comparison between triggered and real-time PDHI shows obviously differences in the DI signal detection due to the different microbubble behavior. Clinicians should be aware of the potentials of MCE to improve noninvasive diagnostic procedures in patients with ischemic heart disease.

Albumins↗
PubMed2003

[Peripartum cardiomyopathy-the (un)known obstetricalcardiologic emergency situation].

Peripartum cardiomyopathy (PPCM) is rare cardiac complication afflicting women during pregnancy or until 5 months post partum with the typical signs of acute cardiac failure. PPCM is similar to dilated cardiomyopathy (DCM) in terms of symptoms, histopathology and treatment but is characterized by a better outcome with a high rate of spontaneous normalization of left-ventricular size and function. The understanding of the etiology is limited. However, viral myocarditis and autoimmune factors might be involved in the development of PPCM. Clinically, PPCM shows pulmonary symptoms such as dyspnea, tachypnea and coughing. The diagnosis is finally established by echocardiography. It has to be assumed that PPCM is often undetected or misdiagnosed because of the low incidence, the unspecific symptoms and the fact that other pregnancy-related factors have similar clinical appearance. The treatment is also unspecific and similar to DCM and acute cardiac failure. The severity of the disease requires an interdisciplinary approach in a perinatal center with consequent follow-up of the patients for risk stratification including echocardiography.

Adult↗