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M Vogel

Publications and source records attributed to M Vogel.

At least 37 records · Page 2Linked to original sources
PubMed2005

Sildenafil in neonatal pulmonary hypertension due to impaired alveolarisation and plexiform pulmonary arteriopathy.

We report a case of severe pulmonary hypertension in a neonate associated with impaired alveolarisation and plexiform pulmonary arteriopathy. Treatment with oral sildenafil in addition to inhaled nitric oxide (NO) resulted in recovery from the pulmonary hypertensive crisis. Long term sildenafil therapy was associated with complete resolution of the pulmonary hypertension.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2004

Pulmonary regurgitation is an important determinant of right ventricular contractile dysfunction in patients with surgically repaired tetralogy of Fallot.

BACKGROUND: Evaluation of right ventricular (RV) function in patients with pulmonary regurgitation (PR) after tetralogy repair remains challenging because of abnormal RV loading conditions. METHODS AND RESULTS: We examined 124 patients, aged 21+/-11.4 years, who had tetralogy repair at 3.7+/-3.5 years. By Doppler echocardiography, 33 patients had mild, 22 moderate, and 69 severe PR; 55 had significant tricuspid regurgitation (TR). Myocardial velocities, myocardial acceleration during isovolumic contraction (IVA), strain, and strain rate were measured at RV and LV base. Tricuspid valve annulus was measured in a 4-chamber view. QRS, QT, and JT intervals and their dispersions were measured from 12-lead electrocardiogram. IVA in the RV was lower in all patients compared with controls (0.8+/-0.4 versus 1.8+/-0.5, P<0.0001) and correlated with the severity of PR (r=-0.43, P<0.0001), whereas myocardial velocities, and strain/strain rate did not. LV IVA correlated with PR (r=-0.32, P<0.001) and with RV IVA (r=0.28, P<0.003). Patients with severe PR had a higher incidence of TR (r=0.69, P<0.0001) and lower RV IVA (1.0+/-0.4 versus 0.6+/-0.3, P<0.0001), a larger tricuspid valve ring diameter (P<0.0001), and prolonged electrical depolarization (P<0.001). Age at surgery or examination did not correlate with PR and with RV function assessed by IVA. In the RV, IVA correlated inversely with QRS duration (P<0.01). CONCLUSIONS: Although load-dependent myocardial velocities and strain are not influenced by the severity of PR and presence of significant TR, IVA demonstrates reduced contractile function in relation to the degree of PR and may be an early, sensitive index for selecting patients for valve replacement.

Adolescent↗
PubMed2004

Therapy of hepatitis C in HIV-coinfection.

One third of all European and American HIV-patients are coinfected with hepatitis C. HIV accelerates hepatitis C virus liver disease especially when HIV-associated immune deficiency progresses. Indeed, liver cirrhosis rate is five times higher in HIV/HCV-coinfected patients than in HCV-monoinfected patients. With the introduction of pegylated interferon and ribavirin combination therapy sustained virological response rates of up to 40 % could be obtained in HIV/HCV-coinfected individuals. Moreover, cohort analyses could demonstrate that with the use of highly active antiretroviral therapy (HAART) an improved course of hepatitis C and a reduction in liver disease-associated mortality can be achieved. Under consideration of the increased rate of hepatotoxicity due to the presently available antiretroviral treatment regimens in HIV/HCV coinfected patients, however, the development of treatment strategies and guidelines for management of hepatitis coinfection in HIV remains of great clinical significance.

Antiretroviral Therapy, Highly Active↗
PubMed2004

Electronic g factor of hydrogenlike oxygen 16O7+.

We present an experimental value for the g factor of the electron bound in hydrogenlike oxygen, which is found to be g(expt)=2.000 047 025 4 (15)(44). The experiment was performed on a single 16O7+ ion stored in a Penning trap. For the first time, the expected line shape of the g-factor resonance is calculated which is essential for minimizing the systematic uncertainties. The measurement agrees within 1.1 sigma with the predicted theoretical value g(theory)=2.000 047 020 2 (6). It represents a stringent test of bound-state quantum electrodynamics to a 0.25% level. Assuming the validity of the underlying theory, a value for the electron mass is obtained: m(e)=0.000 548 579 909 6 (4) u. This value agrees with our earlier determination on and allows a combination of both values which is about 4 times more precise than the currently accepted one.

Journal Article↗
PubMed2004

Particle dynamics and the development of string-like motion in a simulated monoatomic supercooled liquid.

The microscopic details of local particle dynamics is studied in a glass-forming one component supercooled liquid modeled by a Dzugutov potential developed for simple metallic glass formers. Our main goal is to investigate particle motion in the supercooled liquid state, and to ascertain the extent to which this motion is cooperative and occurring in quasi-one-dimesional, string-like paths. To this end we investigate in detail the mechanism by which particles move along these paths. In particular, we show that the degree of coherence--that is, simultaneous motion by consecutive particles along a string--depends on the length of the string. For short strings, the motion is highly coherent. For longer strings, the motion is highly coherent only within shorter segments of the string, which we call "microstrings." Very large strings may contain several microstrings within which particles move simultaneously, but individual microstrings within a given string are temporally uncorrelated with each other. We discuss possible underlying mechanism for this complex dynamical behavior, and examine our results in the context of recent work by Garrahan and Chandler [Phys. Rev. Lett. 89, 035704 (2002)] in which dynamic facilitation plays a central role in the glass transition.

Journal Article↗
PubMed2004

[Gestational trophoblastic disease, Villous gestational trophoblastic disease].

Gestational trophoblastic disease (GTD) represents a wide range of clinical and pathological distinct entities. The villous forms of GTD includes developmental disorders of the placental tree, like blighted ovum, embryonal, partial and complete moles. The risk of persistent GTD is estimated of 2-14% in partial and up to 50% in complete moles. So, the morphologic differentiation between the different entities of villous forms of GTD is clinical very important. Sometimes, early forms of complete moles (up to 12th weeks of gestation) may represent diagnostic problems, even in the diagnosis of regressive alterations of the placental villous tree after intrauterine retention.

Female↗
PubMed2004

[Gestational trophoblastic disease. Non-villous forms of gestational trophoblastic disease].

The non-villous forms of gestational trophoblastic disease (GTD) include a wide range of morphologic different lesions and cover a wide range of differential diagnosis. Choriocarcinomas (CCA) represent the most malignant form displaying a dimorphic pattern with proliferation of syncytio- and zytotrophoblast. An early start of chemotherapy is of great prognostic impact. Placental site nodule (PSN) and exaggerated placental site (EPS) are non-neoplastic lesions of the intermediate trophoblast without tumorous appearance, whereas placental site trophoblastic tumor (PSTT) and epitheloid trophoblastic tumor (ETT) represent tumorous neoplasms with a potential for local invasion and metastases. PSNs are incidental findings of highly polymorphic cells. In EPS chorionic villi are almost present, endometrial glands and spiral arteries are completely engulfed by intermediate trophoblastic cells without necroses. In PSTT the monomorphic, occasional multinucleated giant cells separating individual muscle fibers and charactersitically blood vessel walls are extensively replaced by trophoblastic cells and fibrinoid material. The ETT consists large necrotic areas with hyalinisation. Typically small blood vessels with preserved walls are located within the center of glycogen-rich monomorphous proliferation of trophoblastic cells.

Choriocarcinoma↗
PubMed2004

Safety, efficacy and development of resistance under the new protease inhibitor lopinavir/ritonavir: 48-week results.

BACKGROUND: Within this open-label, uncontrolled prospective trial we evaluated safety, efficacy and development of genotypic resistance under the new protease inhibitor lopinavir/ritonavir (LPV/r) in antiretroviral (ARV) HIV patients. PATIENTS AND METHODS: 58 patients with virological failure under their current ARV therapy were started on a LPV/r containing regimen. Median baseline HIV RNA and CD4 count were 4.6 log(10) cps/ml (range 2.1-6.4) and 128 x 10(6)/l (0-767), respectively. CD4 count, HIV RNA and metabolic parameters were assessed at weeks 0, 4, 8, 12, 16, 24, 32, 40, 48. Genotypic resistance testing was performed at baseline and again at weeks 12, 24 and 48 in the event of virological failure. RESULTS: Until week 48, viral load (VL) decreased by a median of 1.9 log(10) cps/ml (-0.8-3.8). A VL below 80 cps/ml was found in 20/58 patients (34.5%) at week 48. In parallel, CD4 cells increased to a median of 332 x 10(6)/l (8-905). Nine patients discontinued study treatment. At 48 weeks, median triglyceride and cholesterol levels increased significantly. While the median number of overall protease mutations at baseline was four in all patients, it was six in patients virologically failing on LPV/r. The average number of mutations increased significantly to eight at week 48. Several mutations were detected considerably more often in the event of failure than in response to treatment, e. g. at amino acid positions 10, 24, 54, 71, 82, 84. CONCLUSION: LPV/r is effective in heavily pretreated patients. Discontinuation due to adverse events is infrequent. No individual mutation can be associated with failure on LPV/r. However, a greater number of protease mutations at baseline is associated with poorer treatment outcome and several mutations seem to be related to treatment failure.

Adult↗
PubMed2003

Randomised trial on the influence of continuous magnesium infusion on arrhythmias following cardiopulmonary bypass surgery for congenital heart disease.

OBJECTIVES: To check the hypothesis that continuous magnesium infusion protects the heart from arrhythmias following cardiopulmonary bypass surgery for congenital heart disease. DESIGN: A prospective randomised placebo-controlled study, with patients stratified in three weight groups. PATIENTS AND PARTICIPANTS: The study group ( n=65) postoperatively received a magnesium infusion (1 mmol/kg), the control group ( n=66) received placebo. In both groups serum and ionised magnesium values were followed, and all postoperative arrhythmias were documented for 24 h. MEASUREMENTS AND RESULTS: Serum and ionised magnesium in the blood was elevated after the end of bypass (0.54+/-0.15 mmol l(-1) pre-operatively, 0.88+/-0.24 mmol l(-1) postoperatively), where a cardioplegia solution containing magnesium was used. Magnesium values remained at this elevated level in the magnesium therapy group, and decreased to normal pre-operative values within 24 h in controls ( P<0.001). The incidence of postoperative arrhythmias was lower in the study group: 8/65 in the study group and 17/66 in the control group, respectively (chi-squared test, P=0.05). Lower patient weight (32.7 kg versus 22.6 kg), longer cardiopulmonary bypass time (128.7 min versus 87.9 min) and deeper body temperature during extracorporeal circulation (29.2 degrees C versus 32.6 degrees C) were identified as risk factors for postoperative arrhythmias ( P<0.05). CONCLUSIONS: Continuous magnesium infusion effectively reduces the rate of arrhythmias following cardiopulmonary bypass surgery for congenital heart disease and should, therefore, be routinely used.

Arrhythmias, Cardiac↗
PubMed2003

Thermal fluctuations and positional correlations in oriented lipid membranes.

We have determined the positional correlation functions in aligned stacks of fully hydrated phospholipid bilayers from the thermal diffuse scattering measured by nonspecular x-ray reflectivity. While fair agreement can be obtained between experiment and linear smectic theory at length scales above 120 A, significant deviations occur at small r, which are tentatively attributed to collective protrusion modes.

Biomimetic Materials↗
PubMed2003

Tissue Doppler echocardiography in patients with thalassaemia detects early myocardial dysfunction related to myocardial iron overload.

AIMS: To compare an echocardiographic method for detecting abnormal cardiac function before development of overt cardiomyopathy with a recently validated technique of quantifying myocardial iron load. METHODS AND RESULTS: We examined thalassaemia patients whose myocardial iron load had been evaluated with magnetic resonance imaging (MRI). By tissue Doppler echocardiography, myocardial velocities were sampled continuously from base to apex in the RV and LV free wall, and the septum in 52 patients aged 29.2 (14.2-43.1) years and 52 age-matched controls. Ninety-six percent of patients had normal LV ejection fraction by MRI. Thirty-eight (73%) had abnormal iron loading of the myocardium, and 33 of those had regional wall motion abnormalities detected in the septum (n=29), LV (n=2), RV (n=1), and septum plus LV (n=1). The incidence of wall motion abnormalities was significantly higher (P<0.04) in patients with myocardial iron overload (87%) than in the 14 without (35%). Furthermore, myocardial iron overload was suggested by a low T2(*)(15.1+/-15.8 ms) in patients with wall motion abnormalities vs those with normal wall motion (T2(*): 30+/-19 ms) (P<0.007). CONCLUSIONS: Wall motion abnormalities may represent an early sign of cardiac disease despite preserved global function. The regional abnormalities are related to iron overload and easily detectable with tissue Doppler echocardiography.

Adolescent↗
PubMed2003

Photodissociation of small group-11 metal cluster ions: fragmentation pathways and photoabsorption cross sections.

Noble metal cluster ions Cu(n)(+), Ag(n)(+) and Au(n)(+) (n = 3-21) have been stored in a Penning trap and photodissociated by low intensity laser pulses of 10 ns at photon energies of 3.49 eV and 4.66 eV. The fragmentation pathways, neutral monomer and dimer evaporation, have been monitored as a function of cluster size, excitation energy and element. It is found that the behavior of the branching ratio between monomer and dimer evaporation as a function of excitation energy depends on the metal under investigation. In particular, the slope of the energy dependence is positive for silver but negative for gold and copper cluster ions. Furthermore, photoabsorption cross sections are determined from observed total fragment yields in single-photon dissociation.

Journal Article↗
PubMed2003

Kinematical analysis of emotionally induced facial expressions in patients with obsessive-compulsive disorder.

UNLABELLED: BACKGROUND; Motor function is deficient in many patients with obsessive-compulsive disorder (OCD), especially in the face. To investigate subtle motor dysfunction, kinematical analysis of emotional facial expressions can be used. Our aim was to investigate facial movements in response to humorous film stimuli in OCD patients. METHOD: Kinematical analysis of facial movements was performed. Ultrasound markers at defined points of the face provided exact measurement of facial movements, while subjects watched a humorous movie ('Mr Bean'). Thirty-four OCD patients (19 male, 15 female; mean (S.D.) age: 35.8 (11.5) years; mean (S.D.) total Y-BOCS score: 25.5 (5.9)) were studied in unmedicated state and after a 10-week treatment with the SSRI sertraline. Thirty-four healthy controls (19 male, 15 female; mean (S.D.) age: 37.5 (13.1) years) were also investigated. RESULTS: At baseline, OCD patients showed significantly slower velocity at the beginning of laughing than healthy controls and a reduced laughing frequency. There was a significant negative correlation between laughing frequency and severity of OCD symptoms. Ten weeks later a significant increase of laughing frequency and initial velocity during laughing was found. CONCLUSIONS: Execution of adequate facial reactions to humour is abnormally slow in OCD patients. Susceptibility of OCD patients with regard to emotional stimuli is less pronounced than in healthy subjects. This phenomenon is closely correlated to OCD symptoms and is state-dependent.

Adult↗
PubMed2003

[Evaluation of left ventricular volumes in patients with congenital heart disease and abnormal left ventricular geometry. Comparison of MRI and transthoracic 3-dimensional echocardiography].

PURPOSE: To assess the new method of 3-dimensional echocardiography in comparison to the "gold standard" MRI as to its ability to calculate left ventricular volumes in patients with congenital heart disease. MATERIALS AND METHODS: Eighteen patients between the ages of 3.9 to 37.3 years (mean: 12.8 +/- 9.7) with a geometrically abnormal left ventricle were examined using a 1.5T scanner with a fast gradient-echo sequence (TR = 14 ms, TE = 2.6 - 2.9 ms, FOV = 300 - 400 mm, flip angle = 20 degrees, matrix = 128 : 256, slice thickness = 5 mm, retrospective gating) in multislice-multiphase technique. Transthoracic 3D-echocardiography was performed with a 3.5 MHz transducer and a Tomtec (Munich, Germany) system for 3D reconstruction. RESULTS: Volume calculation was possible in all patients with 3D-echocardiography, but the muscle mass calculation only succeeded in 11 of 18 patients (61 %) due to inadequate visualization of the entire myocardium. Comparing MRI and 3D-echocardiography, the correlation was r = 0.97 for the end-systolic volumes, r = 0.98 for the end-diastolic volumes, r = 0.79 for the end-systolic muscle mass and r = 0.77 for the end-diastolic muscle mass. The agreement between both methods was considered good for the calculated end-diastolic volumes and sufficient for the calculated end-systolic volumes. The muscle mass calculations showed larger differences especially for the end-systolic mass. Mean intraobserver variability was 18.6 % for end-systolic and 8.3 % for end-diastolic volumes. CONCLUSION: In patients with an abnormal left ventricular configuration due to congenital heart disease, the new method of 3D-echocardiography is sufficient for volume calculations in preselected patients. The high intraobserver variability is still a limitation of transthoracic 3D-echocardiography in comparison to MRI.

Adolescent↗
PubMed2003

Successful therapy of tardive dyskinesia in a 71-year-old woman with a combination of tetrabenazine, olanzapine and tiapride.

There is no generally accepted treatment for tardive dyskinesia following intake of neuroleptics. Many compounds with effects on serotonine, GABA, cholinergic or dopamine receptors have been clinically useful. We report on a 71-year-old female patient suffering from orofacial tardive dyskinesia after treatment with haloperidol, which did not respond to monotherapy with antidyskinetic drugs. The syndrome disappeared almost completely within two weeks after a multidrug approach consisting of tetrabenazine, olanzapine and tiapride. A combination of antidyskinetic drugs should be considered in patients with severe tardive dyskinesia.

Aged↗
PubMed2002

[Pediatric dermatotherapy].

Dermatological therapy of children differs considerably from treatment of adults and poses a special challenge. Dermatological diseases often form idiosyncratic entities with a prognosis different from adults and must be treated appropriately. Consideration should also be given to the fact that children occasionally experience adverse reactions to drugs, which are not observed in adults. A selection of dermatological diseases and typical drug reactions are presented to illustrate the special features and differences between pediatric dermatotherapy and treatment of adults.

Administration, Oral↗