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M Beer

Publications and source records attributed to M Beer.

At least 37 records · Page 2Linked to original sources
PubMed2002

Aseptic necrosis of both femoral heads as first symptom of chronic myelogenous leukemia.

Chronic myelogenous leukemia (CML) is a disease of the elderly; in rare cases it occurs in childhood or adolescence. One complication at primary diagnosis is leukostasis, which usually causes respiratory, retinal, or central nervous symptoms. In this report we describe the case of a 24-year-old woman who developed aseptic necrosis of both femoral heads, which was successfully treated by bore holes in the femoral heads. This is a very rare complication of severe leukostasis, leading to the diagnosis of CML in this case. To our knowledge, this is the first case of an adult patient showing aseptic necrosis of femoral heads caused by leukostasis.

Adult↗
PubMed2002

Differential diagnosis of lymphadenopathy: power Doppler vs color Doppler sonography.

Our objective was to compare color and power Doppler sonography of superficial lymph nodes. One hundred ninety-three lymph nodes in 161 patients were assessed by color and power Doppler sonography using standardized settings. We tested which modality displayed more intranodal vessels and checked if these differences would have altered the diagnosis. Additional vessels were seen by color Doppler sonography in 18 nodes and by power Doppler sonography in 58 nodes. Amongst those nodes were 15 nodes which showed no vascularization in color Doppler sonography and 23 nodes with only few intranodal flow signals; however, the better sensitivity of power Doppler sonography had no impact on the diagnosis in 42 of 58 nodes. Diagnostic confidence was increased in 7 nodes which showed normal vessels only in power Doppler sonography, although missing flow signals were defined as a benign finding. Pathological vessels were displayed only by power Doppler sonography in 9 nodes, but 6 of these 9 results proved to be false positive. Power Doppler sonography displays more intranodal flow signals than color Doppler sonography, but the diagnostic impact is low because of an increased risk of false-positive results.

Adult↗
PubMed2002

[Spondyloarthritis].

Explore the source record for details and available documents.

Cross-Sectional Studies↗
PubMed2002

Phylogenetic analysis of the 5'-untranslated region of german BVDV type II isolates.

On the basis of genetic differences, bovine viral diarrhoea viruses (BVDV) are subclassified into two distinct genotypes, BVDV type I and BVDV type II. We selected German BVDV type II isolates using the BVDV type I-specific monoclonal antibody WB160 and flow cytometric analysis for further characterization. For molecular characterization, a 288-bp fragment of the 5'-untranslated region (5'-UTR) of the selected isolates was investigated by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. Sequence comparisons of the partial 5'-UTR sequences and their phylogenetic analyses demonstrated that the 18 German BVDV type II isolates all belong to either subtype IIa (10 isolates) or subtype IIc (eight isolates). Nevertheless, the German BVDV type II isolates were genetically different (89.9-94.3% sequence identity) from the standard BVDV type II strain 890 from North America, which was recently classified as BVDV type IIa. Furthermore, a clear subdivision of the German BVDV type II isolates into two distinct subtypes (BVDV IIa Germany and BVDV IIc Germany) is shown. Viruses of both subgroups differed in the analysed 5'-UTR fragment from each other (91.6-95.2% sequence identity), but were highly conserved within the same German subtype (97.2-100% sequence identity). These findings are discussed in the context of BVDV type II origin, possible introduction into Germany, its epidemiology and impact for vaccine development.

5' Untranslated Regions↗
PubMed2002

Quantitative analysis of energy metabolism in human muscle using SLOOP 31P-MR-spectroscopy.

OBJECTIVE: Energy metabolism is vital for regular muscle function. In humans, in-vivo analysis using (31)P-MR-spectroscopy (MRS) is mostly restricted to semiquantitative parameters due to technical demands. We applied Spatial Localization with Optimal Pointspread Function (SLOOP) for quantification in human skeletal and cardiac muscle. SUBJECTS/METHODS: 10 healthy volunteers and 4 patients with myotonic dystrophy type 1 were examined using a 1.5 T system (Magnetom VISION) and chemical shift imaging (CSI) for data collection. Concentrations of PCr, ATP and Pi as well as PCr/ATP ratios were calculated by SLOOP. RESULTS: Concentrations of PCr, ATP and Pi were 29.9 +/- 3.4, 7.1 +/- 0.9 and 5.7 +/- 1.2 [mmol/kg] in normal skeletal muscle, corresponding to previously published studies. Two of the patients with a duration of disease longer than 10 years and a pronounced muscle weakness showed a significant decrease of PCr and ATP in skeletal muscle below 10 and 5 mmol/kg. One of these patients had an additional reduction of PCr in cardiac muscle. CONCLUSIONS: With MRS and SLOOP, a more accurate quantitative assessment of metabolism is now available in skeletal and cardiac muscle. Longitudinal studies of larger patient groups will allow to better describe the metabolic disorder in muscle disease over time. Moreover, these techniques offer a new way to quantify treatment effects in future trials.

Adult↗
PubMed2002

Metallic stents and plastic endoprostheses in percutaneous treatment of biliary obstruction.

BACKGROUND: In the light of the clinical controversy whether metallic stents or plastic endoprostheses should be used in the percutaneous treatment of biliary obstruction we retrospectively evaluated our experience with both drainage-systems. METHODS: 71 patients (mean age 68 +/- 12 years) underwent a total of 81 interventions and received either plastic endoprostheses (11.5 or 12 French diameter; N = 57/81) or metallic stents (N = 24/81). RESULTS: Drainage insertion was technically successful in all of the 71 patients. There was no procedure-related mortality, but a 30-day mortality of 15 % (N = 11). Overall, 27 complications occurred in 81 interventions with a statistically significant higher complication-rate in plastic endoprostheses (39 %; N = 21/54) compared to metallic stents (22 %; N = 6/27). The average patency of the drainage-systems was 166 +/- 341 days (range 1-2,705 days) and did not differ significantly between the drainage-subtypes. Incidence of complications and a further increase in serum bilirubin following intervention was associated with a higher drainage occlusion-rate and reduced survival, irrespective of the drainage-system used. CONCLUSIONS: Percutaneous transhepatic treatment of biliary obstructions with internal drainages is a reliable therapy. The overall complication-rate of metallic stents was lower compared to plastic endoprostheses; however, no significant differences were found with respect to drainage patency or success-rate.

Adult↗
PubMed2002

[Interindividual-variability of the analysis of regional myocardial wall function after myocardial infarction and revascularization].

PURPOSE: The gold standard for diagnosis myocardial viability is the functional recovery after revascularization. Aim of the study was to compare (1) qualitative analysis and (2) quantitative wall thickening by cine MRI and (3) circumferential shortening by tagged MRI the analysis of regional wall function of an infarcted area before and after revascularization. MATERIAL AND METHODS: Ten patients (age 60 +/- 11 years) with infarct-associated regional left ventricular wall motion abnormalities were examined by cine and tagged MRI on average two weeks after the myocardial infarction and re-examined three months after revascularization. Eight healthy volunteers served as a control for tagged MRI. Interobserver-variabilities of two observers were calculated using the kappa-statistics for grading of wall motion abnormalities as well as for detection of functional recovery by qualitative analysis, measurement of wall thickening of cine MRI, and measurement of circumferential shortening by tagged MRI, respectively. RESULTS: Grading of wall motion abnormalities revealed interobserver-variabilities of the study and control group of kappa = 0.8 and kappa = 0.84, kappa = 0.02 and kappa = 0.5, and kappa = 0.1 and kappa = 0.17 for qualitative analysis, wall thickening analysis and measurement of circumferential shortening, respectively. The interobserver-variability for the definition of wall motion recovery was kappa = 0.8 for all three methods. CONCLUSION: Qualitative analysis of wall motion abnormalities has the lowest interobserver-variability for the grading of wall motion abnormalities. The interobserver-variabilities of qualitative and quantitative analysis are comparable for the diagnosis of regional wall motion recovery. Thus, qualitative analysis of cine MRI can be used for grading regional wall motion in clinical studies.

Aged↗
PubMed2002

Role of "G-bacteria" in anaerobic substrate uptake in a SBR with no phosphorus removal.

Biomass from an SBR running with no enhanced biological phosphorus removal (EBPR) but which exhibited anaerobic assimilation of glucose and acetate, was dominated by "G-bacteria", cocci in tetrads and clusters. Extracted 16S rDNA was amplified by PCR and then analysed using Denaturing Gradient Gel Electrophoresis (DGGE). Major bands were extracted and their sequences determined. Clone libraries were also prepared, the 16S rDNA extracted, PCR performed and the resultant fragments run by DGGE to aid in identifying the DGGE bands and provide fuller sequences than available by DGGE alone. The two approaches together allowed several bands to be identified. Probes for FISH analyses were designed for some of these in attempts to see to which phylogenetic group "G-bacteria" belonged, and whether they represented the dominant bands detected by DGGE. Then FISH/Microautoradiography (MAR) was used in attempts to see which bacteria there were assimilating substrates anaerobically. Results indicated that the "G-bacteria" were phylogenetically diverse, but mainly alpha-proteobacteria and members of the high G+C% gram-positive bacteria. Not all of these could assimilate glucose and/or acetate anaerobically, and Amaricoccus, the original "G-bacteria" of Cech and Hartman, was not detected.

Bacteria, Anaerobic↗
PubMed2001

Optimization of ECG-triggered 3D (23)Na MRI of the human heart.

(23)Na MRI may allow distinction of normal and ischemically injured myocardium. The aim of this study was to optimize (23)Na MRI of the human heart by improvement of spatial resolution and ECG-triggering and to measure the signal/noise of blood and myocardium and the myocardium/blood signal ratios in a volunteer study. A spoiled gradient echo sequence was developed on a 1.5T scanner equipped with a (23)Na heart surface coil. 3D short axis ECG-triggered (23)Na MRI was performed in 10 healthy subjects. The signal/noise of myocardium and blood were 8.2 +/- 0.7 and 18.3 +/- 1.3, respectively, signal ratio myocardium/blood was 0.44 +/- 0.03. This value is in good agreement with the theoretical value of 0.45. ECG gated 3D (23)Na MRI of the human heart is feasible with sufficient spatial resolution and signal/noise ratio. Magn Reson Med 45:164-166, 2001.

Adult↗
PubMed2001

Time course of contrast enhancement patterns after Gd-BOPTA in correlation to myocardial infarction and viability: a feasibility study.

Our objective was to analyze contrast enhancement patterns (CEP) and their time course after myocardial infarction (MI) following injection of Gd-BOPTA in correlation with recovery of regional function. Seven patients with subacute MI (18 +/- nine days) were examined before, as well as three and six (n = six) months after, revascularization of the infarct-related artery. Regional wall motion abnormalities were assessed by cine-MRI, and repetitive images of one representative slice were acquired up to 45 minutes after 0.05 mmol/kg Gd-BOPTA using a T1-w TSE-sequence. Two patients showed mid-wall/subendocardial, one patient subendocardial enhancement of MI associated with mechanical improvement after revascularization. Three patients without improvement revealed a mid-wall hypoenhanced zone within the first five minutes after injection, which was unchanged at follow-up. One patient with partial functional improvement showed transmural enhancement and a mid-wall hypoenhanced zone in adjacent areas. With this feasibility study, we concluded that mid-wall and/or subendocardial enhancement after Gd-BOPTA was associated with viable myocardium, whereas detection of microvascular obstruction correlating with scar formation is suggested by mid-wall hypoenhancement within the first five minutes after injection.

Adult↗
PubMed2001

Advances in human cardiac 31P-MR spectroscopy: SLOOP and clinical applications.

Phosphorus magnetic resonance spectroscopy (31P-MRS) has revealed a lot about the biochemistry of physiological and pathological processes in the heart. Nevertheless, until today, cardiac 31P-MRS has not had any clinical impact, albeit some pioneering studies demonstrated that 31P-MRS can indeed provide diagnostic information. In this paper, the development of techniques for human cardiac 31P-MRS over the past decade is reviewed, and the requirements for a reliable clinical measurement protocol are discussed. Spatial localization with optimal pointspread function (SLOOP) is a new method to achieve spatial localization and absolute quantitation. Its properties are detailed, and preliminary findings in patients with dilated cardiomyopathy or myocardial infarction are presented.

Heart Diseases↗
PubMed2001

(31)P-MR Spectroscopy for the evaluation of energy metabolism in intact residual myocardium after acute myocardial infarction in humans.

OBJECTIVE: Experimental studies have demonstrated that acute myocardial infarction (MI) alters energy metabolism even in non-infarcted adjacent tissue. In patients with subacute MI, the influence of the regional ischemic insult on energy metabolism of intact septal myocardium was analyzed using 31P-Magnetic resonance spectroscopy (MRS). PATIENTS AND METHODS: In eight patients with wall motion abnormalities in the anterior wall 31P-spectra were obtained from non-infarcted adjacent septal myocardium, as well as infarcted anterior myocardium (voxel size 25 ccm each) 29+/-8 days after MI using a 3D-CSI technique. Additionally, cardiac function was analyzed using breath-hold cine MRI. MRI was repeated 6 months after revascularization to assess viability of infarcted segments. Eight age-matched healthy volunteers served as control group. RESULTS: According to follow-up MRI 4/8 patients showed regional wall motion recovery. Here, PCr/ATP-ratios were not significantly reduced in intact septal myocardium as well as infarcted anterior myocardium compared to healthy volunteers (1.28+/-0.10 and 1.14+/-0.09 vs. 1.45+/-0.29). No recovery of regional function was detected in 4/8 patients with-therefore-non-viable anterior myocardium. PCr/ATP-ratios were significantly reduced in intact and infarcted myocardium compared with healthy volunteers as well as to patients with wall motion recovery (0.77+/-0.17 and 0.49+/-0.23; P<0.05). DISCUSSION: These preliminary results indicate that energy metabolism is reduced in patients with persisting wall motion abnormalities after myocardial infarction and revascularization in ischemically injured as well as in adjacent non-injured myocardium.

Aged↗
PubMed2001

Optimization of automatic bolus tracking for timing of the arterial phase of helical liver CT.

The aim of this study was to optimize bolus tracking for timing of the arterial phase of biphasic helical liver CT and to compare optimized bolus tracking to a standard delay. One hundred fifty patients were examined with six protocols: 5- or 10-s delay after triggering at a threshold of 50 or 75 or 100 HU enhancement in the aorta at the origin of the celiac arteries after injection of 120 ml contrast material at 3 ml/s. Optimal arterial enhancement was defined as 20-30% of hepatic enhancement in portal venous phase. Another 50 patients were examined with the optimized protocol and compared to 50 gender- and age-matched patients who underwent a 25-s standard delay. A 10-s delay after the 75-HU threshold resulted in the most patients with an optimal arterial phase (p < 0.01). Thirty-one of 75 patients examined with this protocol showed optimal early liver enhancement. Bolus tracking compared with standard delay revealed only a trend for a difference (p = 0.07). The outcome of automatic bolus tracking differs depending on the protocol used; however, optimal arterial phase imaging was seen in only 41% of patients, indicating only a trend for superior timing compared with a standard delay.

Adolescent↗
PubMed2001

Breath-hold 3D MR coronary angiography with a new intravascular contrast agent (feruglose)--first clinical experiences.

Demonstration of the initial results of breath-hold 3D MR coronary angiography with patients using a new intravascular contrast agent (feruglose). Contrast-enhanced 3D MR-coronary angiography was performed in 5 patients with coronary artery disease after administration of feruglose in three different doses (0.5 (n = 3), 2, 5 mg Fe/kg body weight for each patient). MR coronary angiography was performed with an ECG-triggered 3D-FLASH-sequence during breath-hold at 1.5 T (TR 6.8 ms, TE 2.5 ms, flip-angle 30 degrees ). To reduce data acquisition time, only the two anterior elements of the phased-array body coil were activated. The data acquisition window within the cardiac cycle ranged between 217-326 ms depending on the matrix. Signal-to-noise (SNR) and contrast-to-noise ratios (CNR) of the coronary arteries were analyzed, and the results for the detection of coronary artery stenoses were compared with those obtained by conventional coronary angiography. SNR and CNR revealed an improved image quality at a dose of 2 mg Fe/kg compared with the lower dose, but no further improvement was obtained by rising the dose to 5 mg Fe/kg. Except for the left circumflex artery of one patient, at minimum the proximal parts of all four main coronary arteries could be imaged for all patients. Within the visible parts of the coronary arteries, six of eight significant coronary stenoses were identified correctly. Imaging of the proximal parts of the coronary arteries including detection of stenoses is possible during breath-hold using an intravascular contrast agent.

Aged↗
PubMed2001

Cardiac metabolism and function in patients with multiple sclerosis: a combined 31P-MR-spectroscopy and MRI study.

OBJECTIVE: Involvement of the autonomic system in multiple sclerosis (MS) may concur with dysfunction of the cardiovascular system. The introduction of potentially cardiotoxic immunosuppressive drugs like Mitoxantrone into the treatment of MS warrants proper assessment of preexisting heart disease. However, systematic analyses of functional and metabolic derangements in MS are missing. Using quantitative 31P-MR-spectroscopy (MRS) and MR-imaging (MRI) metabolic and functional parameters were analyzed in patients with MS in comparison to healthy volunteers. SUBJECTS/METHODS: 14/15 patients with MS could be included in the study, as the MRS examination of one patient had to be excluded from analysis due to movement during the examination. Using chemical shift imaging (CSI) and AMARES, phosphocreatine (PCr) to adenosine triphosphate (ATP) ratios, characterizing myocardial high-energy phosphate metabolism, were determined. Additionally, absolute concentrations of PCr and ATP were calculated by SLOOP (Spatial Localization with Optimal Pointspread Function). Analysis of functional changes was performed by Cine-MRI. 14 healthy volunteers matched for age and gender served as control. RESULTS: A significant decrease of absolute PCr concentration was observed in patients with MS compared to matched volunteers (p < 0.05), whereas ATP concentrations showed no significant changes (p = 0.27). Metabolite ratios calculated by SLOOP or AMARES showed a tendency to be reduced in patients, however, did not reach significance (p = 0.08, SLOOP; p = 0.47, AMARES). Using volunteers' mean values +/- 2 x SD as cut off value revealed PCr changes in 5 of 14 patients, whereas only 2 also had pathologic PCr/ATP ratios. Functional analysis by MRI depicted depressed left ventricular ejection fraction in 4 patients. CONCLUSIONS: The reduction in cardiac high-energy phosphates in some patients with MS points to a subclinical involvement of the heart. This may be important for treatment with potentially cardiotoxic drugs. Longitudinal studies are need to understand the clinical relevance of our findings.

Adenosine Triphosphate↗
PubMed2001

[31P-MR spectroscopy of all regions of the human heart at 1.5 T with acquisition-weighted chemical shift imaging].

AIM: Aim of this study was to show whether or not acquisition-weighted chemical shift imaging (AW-CSI) allows the determination of PCr and ATP in the lateral and posterior wall of the human heart at 1.5 T. METHODS: 12 healthy volunteers were examined using a conventional chemical shift imaging (CSI) and an AW-CSI. The sequences differed only in the number of repetitions for each point in k space. A hanning function was used as filter function leading to 7 repetitions in the center of the k space and 0 in the corners. Thus, AW-CSI had the same resolution as the CSI sequence. The results for both sequences were analyzed using identically positioned voxels in the septal, anterior, lateral and posterior wall. RESULTS: The determined averaged AW-CSI signal to noise ratios were higher for PCr by a factor of 1.3 and for ATP by 1.4 than those of CSI. The PCr/ATP ratios were higher by a factor of 1.2 - 1.3 and showed a smaller standard deviation in all locations for AW-CSI. The mean PCr/ATP ratios determined by AW-CSI of septal, lateral and posterior wall were almost identical (1.72 - 1.76), while it was higher in the anterior wall (1.9). CONCLUSIONS: The reduced contamination in AW-CSI improves the signal to noise ratio and the determination of the PCr/ATP ratio in cardiac (31)P spectroscopy compared to CSI with the same resolution. The results in volunteers indicate that AW-CSI renders (31)P spectroscopy of the lateral and posterior wall of the human heart feasible for patient studies at 1.5 T.

Adenosine Triphosphate↗
PubMed2001

Structure and functional analysis of the microbial community in an aerobic: anaerobic sequencing batch reactor (SBR) with no phosphorus removal.

The bacterial community of an aerobic:anaerobic non-P removing SBR biomass fed a mixture of acetate and glucose was analysed using several 16S rRNA based methods. Populations responsible for anaerobic glucose and acetate assimilation were determined with fluorescent in situ hybridization (FISH) in combination with microautoradiography (FISH/MAR). At 'steady state' this community consisted of alpha-Proteobacteria (26%) and gamma-Proteobacteria (14%), mainly appearing as large cocci in tetrads (i.e. typical 'G-Bacteria'). Large numbers of low G+C bacteria (22%), and high G+C Gram-positive bacteria (29%) seen as small cocci in clusters or in sheets were also detected after FISH. DGGE fingerprinting of PCR amplified 16S rDNA fragments and subsequent cloning and sequencing of several of the major bands led to the identification of some of these populations. They included an organism 98% similar in its 16S rRNA sequence to Micropruina glycogenica, and ca. 76% of the high G+C bacteria responded to a probe MIC 184, designed against it. The rest responded to the KSB 531 probe designed against a high G+C clone sequence, sbr-gs28 reported in other similar systems. FISH analyses showed that both these high G+C populations were almost totally dominated by small clustered cocci. Only ca. 2% of cells were beta-Proteobacteria. None of the alpha- and gamma-Proteobacterial 'G-bacteria' responded to FISH probes designed for the 'G-Bacteria' Amaricoccus spp. or Defluvicoccus vanus. FISH/MAR revealed that not all the alpha-Proteobacterial 'G-Bacteria' could take up acetate or glucose anaerobically. Almost all of the gamma-Proteobacterial 'G-Bacteria' assimilated acetate anaerobically but not glucose, the low G+C clustered cocci only took up glucose, whereas the high G+C bacteria including M. glycogenica and the sbr-gs28 clone assimilated both acetate and glucose. All bacteria other than the low G+C small cocci and a few of the alpha-Proteobacteria accumulated PHB. The low G+C bacteria showing anaerobic glucose assimilation ability were considered responsible for the lactic acid produced anaerobically by this SBR biomass, and M. glycogenica for its high glycogen content.

Acetates↗