Biomedical subjects

B Schnell

Publications and source records attributed to B Schnell.

10 recordsLinked to original sources

PubMed1999

Safety of deferring angioplasty in patients with normal coronary flow velocity reserve.

BACKGROUND: In the catheter laboratory there is a need for functional tests validating the hemodynamic significance of coronary artery stenosis. OBJECTIVES: It was the objective of our study to compare the long-term cardiac event rate and the clinical symptoms in patients with reduced coronary flow velocity reserve (CFVR) and standard PTCA with patients with normal CFVR and deferred angioplasty. METHODS: Our study included 70 patients with intermediate coronary artery stenoses (13 f, 57 m; diameter stenosis >50%, <90%) and an indication for PTCA due to stable angina pectoris and/or signs of ischemia in noninvasive stress tests. CFVR was measured distal to the lesion after intracoronary administration of adenosine using 0.014 inch Doppler-tipped guide wires. RESULTS: In 22 patients (31%), PTCA was deferred due to a CFVR > or = 2.0 (non-PTCA group). In the remaining 48 patients (69%) mean CFVR of 1.4+/-0.23 (p < 0.001) was measured (PTCA group). CFVR increased to 2.0+/-0.51 after angioplasty. During follow-up (average 15+/-6.0 months), the following major adverse cardiac events (MACE) occurred: in the PTCA group re-PTCA was performed in nine patients (18.8%) because of unstable angina, five patients (10.4%) suffered an acute myocardial infarction (MI) (two infarctions occurred during the angioplasty, three patients suffered an infarction during follow-up), two patients (4.2%) needed blood transfusions due to severe bleedings, two patients (4.2%) underwent bypass surgery and one patient (2.1%) died. In the non-PTCA group, angioplasty was necessary only in two cases (9.1%) during follow-up. We did not observe any MI in the non-PTCA group. The overall rate of MACE was significantly lower in the non-PTCA group compared to the PTCA group (9.1% vs. 33.3%, p < 0.01). However, only 40% of the patients of the non-PTCA group were free of angina pectoris at stress. In the PTCA group, 63% did not complain of any symptoms at follow-up (p < 0.05). CONCLUSIONS: We conclude that determination of the CFVR is a valuable parameter for stratifying the hemodynamic significance of coronary artery stenosis. PTCA can safely be deferred in patients with significant coronary stenosis but a CFVR > or = 2.0. The total rate of MACE at follow-up was below 10% among these patients. However, if PTCA was deferred the number of patients who are free of angina is lower compared to those patients who underwent angioplasty.

Aged↗

PubMed1996

A gradient of cytoplasmic Cactus degradation establishes the nuclear localization gradient of the dorsal morphogen in Drosophila.

Dorsoventral axis formation in the Drosophila embryo is established by a signal transduction pathway that comprises the products of at least 12 maternal genes. Two of these genes, dorsal and cactus, show homology to the mammalian transcription factor NF-kappa B and its inhibitor I kappa B, respectively. As in the case for I kappa B and NF-kappa B, Cactus inhibits Dorsal by retaining it in the cytoplasm. In response to the signal produced and transmitted by the products of the other genes, Dorsal translocates to the nucleus preferentially on the ventral side of the embryo. Here, we show that Cactus forms a cytoplasmic concentration gradient inversely correlated to the nuclear translocation gradient of Dorsal. Deletions of the N-terminus and C-terminus of Cactus reveal that two modes of degradation control cactus activity: signal-induced degradation and signal-independent degradation, respectively. Genetic evidence indicates that degradation of Cactus is required, but not sufficient to translocates Dorsal completely into the nucleus.

Animals↗

PubMed1994

[Preliminary comments on a "History of German medical literature of the middle ages" exemplified by the 12th century].

My long-term goal is to prepare a study leading to a history of medieval German medical literature, from the beginnings to about 1500. This literature is largely missing from the standard histories of medicine, and it also seldom appears in histories of German literature. After reviewing the "überlieferungsgeschichtliche Ansatz", the method of examining texts in the historical and codicological contexts in which they are transmitted, I review the six German medical texts attested in twelfth century manuscripts (not counting individual recipes). These are: the, Prüller Kräuterbuch', the, Prüller Steinbuch', the 'Arzneibuch Ipocratis', the 'Capsula Eburnea', the 'Innsbrucker Arzneibuch', and the 'Frauengeheimnisse', all printed in Friedrich Wilhelm's collection of twelfth century texts. These texts are all from the second half of the century and from the Upper German language area, with Regensburg as the particular focus, and they are transmitted along with important theological and philosophical texts of the time.

Germany↗

PubMed1992

[Magnetic resonance tomography and magnetic resonance angiography in lymphangiomatosis].

Generalised lymphangiomatosis is a rare benign congenital abnormality of the lymphatic vessels with a complex pattern. 3 patients with different types of lymphangiomatosis were studied by MRT and MRA and histopathologically. All patients had multiple organ involvement in the abdomen, the skeleton and the skull. The basis in each case was lymphangiomatosis of capillary-cavernous, cystic or cavernous type. The results of MRT and MRA in diagnosing splenic, vascular and skeletal changes correlated accurately with operative findings and with the histopathological classification. In summary, MRT combined with MRA and using paramagnetic contrast media are the diagnostic methods of choice for the investigation of generalised lymphangiomatosis with multiple organ involvement.

Abdomen↗

PubMed1992

Focal liver lesions: MR imaging with Mn-DPDP--initial clinical results in 40 patients.

Manganese (II) N,N'-dipyridoxylethylenediamine-N,N'-diacetate-5,5'-bis(phosphate) (DPDP) was evaluated as a contrast agent for magnetic resonance (MR) imaging (1.5 T) of focal liver lesions in 40 patients. Doses of 5 and 10 mumol/kg were administered intravenously. Mn-DPDP-enhanced T1-weighted images were compared quantitatively and subjectively with standard T1- and T2-weighted nonenhanced images. Use of Mn-DPDP resulted in a statistically significant increase in signal intensity of liver parenchyma in T1-weighted images at both doses. No enhancement was seen in metastases, cholangiocarcinomas, or lymphomas, while all hepatocellular carcinomas were enhanced. Enhancement was seen in focal nodular hyperplasia and in regenerative nodules. The lesion-to-liver contrast in Mn-DPDP-enhanced gradient-recalled-echo images was superior to that of all precontrast images (P less than .01). The number of nonenhancing malignant liver lesions detected in spin-echo (SE) images was increased (272 in T2-weighted SE images vs 390 in T1-weighted Mn-DPDP-enhanced SE images). Image interpretation (eg, visualization and demarcation of the lesions) was markedly better in Mn-DPDP-enhanced images than in all precontrast images (P less than .001).

Adult↗

PubMed1992

[Magnetic resonance tomography of the hepatobiliary system: indications, limitations and outlook].

In a prospective study we examined the diagnostic value of MRI and MR cholangiography (MRC) in patients suffering from hepatobiliary disease. By using hepatobiliary contrast media (Mn-DPDP, Gd-BOPTA), sensitivity and specificity of MRI were significantly increased. In 65 patients we comparatively analyzed the diagnostic results of MRI and MRC versus ultrasound, CT and invasive techniques such as ERCP. We conclude that the use of MRI and MRC improves the diagnostic evaluation of patients with hepatobiliary disease.

Biliary Tract Diseases↗

PubMed1991

[The clinical value of Mn-DPDP: a new paramagnetic hepatobiliary contrast medium for magnetic resonance tomography of the liver].

In an open prospective study the tolerance and diagnostic value of the new hepatobiliary contrast agent Mn-DPDP in MR imaging was evaluated in 20 patients suspected of having focal liver lesions. T1- and T2-weighted spin-echo sequences and T1-weighted gradient-echo sequences were obtained before and after intravenous application of Mn-DPDP. In all patients the signal to noise (S/N) values of normal liver tissue increased significantly after application of Mn-DPDP. All focal lesions could be better localized and differentiated due to increased contrast to noise ratios of lesion to liver. Pathological examination revealed in 14 patients malignant and in 5 patients benign liver lesions; one patient had no pathological findings. In metastatic disease of the liver 25-120% more lesions could be detected in MRI after Mn-DPDP-application, compared with the unenhanced images. In 5 patients the lesions showed significant enhancement of Mn-DPDP (2 cirrhotic nodules, 2 hepatocellular carcinomas, 1 focal nodular hyperplasia). Our preliminary results indicate that Mn-DPDP is a well-tolerated contrast agent useful for the detection and differentiation of liver lesions in MR imaging.

Adult↗

PubMed1991

[The physician and author. On the participation of physicians in late middle age publishing].

During the 15th century a very great percentage (if not the major part) of German men of letters were physicians. This article concentrates on three of them, all of whom were born in Southern Germany, three of them studied in Italy, wrote during the second third of the century, and became widely renowned as physicians as well as poets or writers of prose. Johannes Hartlieb is well-known as author of a 'Kräuterbuch', but his fame is based mainly on his 'Alexanderroman'. The article tries to show a connection between the two aspects of Hartlieb's work, which have not been related to each other until now: the 'Alexanderroman' is, at least in its central theme, a novel that could only be written by a physician; the traces of the author's profession are obvious. The second part of the article deals with Hermann Schedel. It reconstructs his studies in Padua and then concentrates on five of his manuscripts, which reveal the names and professions of his patients. One may compare Hermann's cousin, Hartmann Schedel to Hartlieb. His 'Weltchronik', which is mainly famous for its illustrations, is the work of a physician, as was Hartlieb's 'Alexander'. Hartmann inserted biographical informations about 40 celebrities among his 'colleagues'. If the 15th century may rightly be called the 'century of the layman', it is because it was the 'century of the physician'.

Authorship↗

PubMed1978

Five year plan.

Explore the source record for details and available documents.

Pharmacy Service, Hospital↗

PubMedDate not supplied

Mn-DPDP enhancement patterns of hepatocellular lesions on MR images.

The recently developed paramagnetic hepatobiliary contrast agent manganese dipyridoxyl diphosphate (DPDP) was evaluated in eight patients. Pathologic diagnoses included five hepatocellular carcinomas, two cirrhoses, and one focal nodular hyperplasia. T1-weighted spin-echo and gradient-echo images were obtained after intravenous injection of 5 or 10 mumol/kg Mn-DPDP; these were compared with unenhanced T1-weighted spin-echo and gradient-echo images and T2-weighted spin-echo images. In all patients with lesions of hepatocellular origin, focal areas of increased enhancement were seen in the lesions after administration of Mn-DPDP. In the cirrhotic livers, these areas corresponded to foci of hepatic regeneration. In all patients, the signal-to-noise ratio in normal liver tissue increased significantly after injection of Mn-DPDP. Signal intensity in the six primary liver tumors was further increased, so that they appeared hyperintense relative to surrounding liver tissue on all T1-weighted images. Conspicuity and demarcation of all lesions were improved on Mn-DPDP-enhanced images.

Adult↗