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K Lackner

Publications and source records attributed to K Lackner.

At least 73 records · Page 4Linked to original sources
PubMed1987

[Results and complications of CT-guided puncture biopsies with a wide-lumen puncture needle].

The results obtained in 187 CT-guided biopsies using a wide lumen needle are described. Biopsies in the thorax, abdomen, retroperitoneum and in the pelvis have been evaluated. A retrospective analysis of the material has shown an accuracy of 97.8% and sensitivity of 95.8%. The total complication rate was 8%. Amongst 120 biopsies in the thorax, 6.6% developed a pneumothorax. Therapeutic drainage was carried out in fifteen patients.

Abdomen↗
PubMed1987

[Rapid MR tomography of the liver. Technic and initial results].

The fast-field-echo (FFE) sequence provides a new rapid imaging method for MR tomography. By using gradient echoes with shorter high frequency pulse repetitions than conventional sequences with 180 degrees echo pulses, it is possible to produce single cuts in 10 to 20 s with good signal-to-noise ratio. In this way the liver can be examined while respiratory movement artifacts are reduced. The possibility of obtaining T1- and T 2-weighted FFE images with good contrast resolution and the ability to determine relaxation times suggests a wide application of this rapid imaging procedure in the diagnosis of liver disease.

Carcinoma, Hepatocellular↗
PubMed1987

[Quantitative regional functional analysis of the left ventricle using ECG-directed cardiac computerized tomography].

ECG-gated cardio-CT using two different methods of subsequent calculation was performed in 152 patients to evaluate contractility of the anterior and posterior wall and apex of the left ventricle quantitatively. The results were compared with RAO laevo-cardiography. Apart from the localisation of abnormal contractility, CT diagnosis showed sensitivity, specificity and accuracy from 70% to 85%. ECG-gated CT was better at showing abnormal movements at the apex and of the anterior wall than of the posterior wall. Attempts to quantify abnormalities of the basis of laevo-cardiographic results.

Adult↗
PubMed1987

[Computed tomography of primary and secondary tumors of the eye and orbit].

Only computed tomography (CT) is able to demonstrate ocular, orbital and peri-orbital soft tissues, calcification and bony structures directly and without superimposition of other tissues. 165 patients with tumours of the eye or orbit have been examined by CT and in 143 the diagnosis has been confirmed. The value of CT lies in its ability to demonstrate tumours and to define their orbital and extra-orbital extension and their relationship to neighbouring structures. In 51% of the lesions there was bone destruction and in 6% intracranial extension. Density measurements before and after intravenous contrast medium only rarely provided a specific diagnosis.

Adolescent↗
PubMed1986

Identification of low density lipoprotein receptor binding domains of human apolipoprotein B-100: a proposed consensus LDL receptor binding sequence of apoB-100.

The human liver apoB-100 gene cloned in the lambda gt-11 expression vector expresses fusion proteins reacting with apoB antibodies. A fusion protein induced from a apoB-lambda gt-11 clone reacted with apoB-100 monoclonal antibodies known to block the binding of LDL to the LDL receptor. The fusion protein contains an amino acid sequence domain enriched in positively charged residues which is complementary to the negatively charged amino acids present in the consensus LDL receptor binding domain. This sequence of apoB-100 is proposed as a binding domain for the interaction with the LDL receptor. Comparison of derived amino acid sequences from the entire structure of apoB-100 molecule revealed several similar domains enriched in positively charged amino acids. A consensus sequence of the potential LDL binding domain was identified which contained positively charged amino acids at positions 1, 5 and 8 and a loop of 8-11 amino acids followed by two adjacent positively charged amino acids. These results are interpreted as indicating that there are several potential LDL receptor binding domains in apoB-100.

Amino Acid Sequence↗
PubMed1986

[Pathogenesis of bleeding esophageal varices].

Pressure in oesophageal varices was measured endoscopically in 52 patients, in 16 of them central portal-vein pressure additionally by percutaneously introduced transhepatic portal-vein catheter. Only in the region of the cardia occlusion segment was the portal-vein pressure the same as that in the oesophageal varices. The larger the varices the higher the average variceal pressure. Depending on the time interval since a meal there were marked pressure variations during the day in portal-vein pressure. Intra-abdominal pressure rise (e.g. on coughing, choking or vomiting) induces a sudden and marked pressure rise in the portal vein as well as the oesophageal varices. The larger the varices the greater the danger of rupture when these pressure rises occur. Gastro-oesophageal reflux plays no role in the pathogenesis of bleeding from oesophageal varices.

Adult↗
PubMed1986

[Indications for preventive sclerosing of esophageal varices].

In 72 patients with oesophageal varices the intravascular oesophageal variceal pressure was measured, in 31 of them the portal pressure as well. The portal pressure was identical with the variceal pressure only at the cardia. There was a positive relationship between the size of varices and the variceal pressure and between the size of varices and the occurrence of bleeding from varices. Prophylactic endoscopic sclerotherapy is indicated in grade II and III varices.

Adult↗
PubMed1986

[Digital subtraction angiography in traumatology].

The methods, indications and results of digital subtraction angiography in traumatology are presented, based on 56 examinations. The different use of intravenous or intraarterial DSA will be discussed with respect to expanding and localisation of traumatic vascular injury. DSA is recommended as the method of choice for follow-up after vascular reconstructive procedure.

Angiography↗
PubMed1986

[Sonography and computed tomography before and after liver resection and transplantation].

The diagnostic value of sonography and CT was studied in 259 patients. In the diagnosis of solid tumours, CT is superior to sonography, whereas ultrasound is more useful in the investigation of cystic lesions. In estimating the extent of intrahepatic tumours, the falciform ligament is more useful than a line from the cava to the gall bladder, both for CT and ultrasound, although in this case CT shows the extent of tumours more accurately. 3.7% of the ultrasound and 2.3% of the CT examinations were of limited value because of unavoidable technical problems.

Carcinoma, Hepatocellular↗
PubMed1986

[Comparison between i.a. DSA and cineangiography for evaluating the coronary arteries and the left ventricle].

In twenty-two patients with coronary heart disease, selective coronary angiography and laevo-cardiography were carried out by means of conventional cine angiography and intra-arterial DSA. For evaluating left ventricular function, intra-arterial DSA and cine angiography were of equal value (r = 0.97). A significant advantage of DSA was the fact that it is easily reproducible. On the other hand, DSA is less good for quantifying coronary stenoses and for demonstrating the peripheral vessels.

Adult↗
PubMed1986

[Radiation exposure of patients and operators during interventional radiology].

Surface doses received by patients and operators were measured during 30 interventional radiological procedures (ten percutaneous transhepatic biliary drainages, ten percutaneous nephrostomies, ten percutaneous transluminal angioplasties). In addition, organ doses to the patient were determined using an Alderson-Rando phantom. These served as a basis for calculating the so-called somatic dose indices. It was found that the somatic radiation risk to the patient is relatively small despite prolonged periods of fluoroscopy. However, exposure of the hands and lenses of the operator could easily reach the limits thought acceptable while carrying out these procedures with additional angiography.

Adult↗
PubMed1986

[Digital subtraction angiography of the aorta].

The results of 300 digital subtraction angiographies of the thoracic and abdominal aorta are analysed. Following intraarterial injection of contrast, all examinations were of good quality. Following I-V DSA, two thoracic (1.8%) and two abdominal (1.2%) aortograms were non-diagnostic. Anomalies in the position of the aorta, dilatation (aneurysm) or stenoses (coarctations, arteriosclerosis, occlusions) could be diagnosed by I-V DSA. One I-A DSA was performed for aneurysm of the ascending aorta in order to evaluate function of the aortic valve and for demonstrating the coronary artery origins, and pre-operatively for an aortic dissection.

Aortic Dissection↗
PubMed1986

[Accuracy of cardiac CT and echocardiography in the diagnosis of space-occupying processes in the heart].

CT of the heart and echocardiography was performed on 107 patients with various space-occupying lesions of the heart. In addition, 27 patients were subjected to angiocardiography. A comparison of the findings has shown that cardio-CT is superior to two-dimensional echocardiography for demonstrating pericardial masses and intracavity thrombi. There was no significant difference as far as intracavity or intramural tumours were concerned. CT and sonography are superior to angiography in the diagnosis of cardiac space-occupying lesions.

Adolescent↗
PubMed1986

[MR tomography of hemophilic arthropathy of the knee joint].

The value of MR tomography in the diagnosis and follow-up of haemophilic arthropathy of the knee was studied in 40 examinations, using special surface coils. Good spatial resolution and reconstruction in various planes provide an accurate demonstration of the lesion, particularly of the intra-articular structures. Abnormalities of the synovia and of hyaline cartilage can be demonstrated. MR tomography is an important imaging method which is superior to sonography or CT in demonstrating complications resulting from the bleeding, such as effusions and haemarthroses.

Adolescent↗
PubMed1986

Human liver apolipoprotein B-100 cDNA: complete nucleic acid and derived amino acid sequence.

Human apolipoprotein B-100 (apoB-100), the ligand on low density lipoproteins that interacts with the low density lipoprotein receptor and initiates receptor-mediated endocytosis and low density lipoprotein catabolism, has been cloned, and the complete nucleic acid and derived amino acid sequences have been determined. ApoB-100 cDNAs were isolated from normal human liver cDNA libraries utilizing immunoscreening as well as filter hybridization with radiolabeled apoB-100 oligodeoxynucleotides. The apoB-100 mRNA is 14.1 kilobases long encoding a mature apoB-100 protein of 4536 amino acids with a calculated amino acid molecular weight of 512,723. ApoB-100 contains 20 potential glycosylation sites, and 12 of a total of 25 cysteine residues are located in the amino-terminal region of the apolipoprotein providing a potential globular structure of the amino terminus of the protein. ApoB-100 contains relatively few regions of amphipathic helices, but compared to other human apolipoproteins it is enriched in beta-structure. The delineation of the entire human apoB-100 sequence will now permit a detailed analysis of the conformation of the protein, the low density lipoprotein receptor binding domain(s), and the structural relationship between apoB-100 and apoB-48 and will provide the basis for the study of genetic defects in apoB-100 in patients with dyslipoproteinemias.

Amino Acid Sequence↗
PubMed1986

The hydronephrotic kidney of the mouse as a tool for intravital microscopy and in vitro electrophysiological studies of renin-containing cells.

Experimental hydronephrosis in mice has been studied with histological, ultrastructural, immunohistochemical, biochemical, and electrophysiological techniques to establish its value as a preparation for the investigation of glomerular microcirculation as well as the electrophysiological and biochemical properties of the renin-containing juxtaglomerular (JG) and vascular smooth muscle (VSM) cells of the afferent glomerular arteriole. During developing hydronephrosis the kidney parenchyma becomes progressively thinner as a result of tubular atrophy, being, after 12 weeks, a tissue sheet of about 200 micron in thickness. In this preparation, the renal arterial tree, in particular the glomerular arterioles, and also the glomeruli can be easily visualized. This permits intravital microscopic studies or direct visual identification of JG and VSM cells for microelectrode impalement. In spite of complete tubular atrophy, the vascular system is well preserved. Ultrastructurally, JG and VSM cells as well as the axon terminals innervating the vessels are intact. The same holds for the glomeruli except for a certain confluence of the podocyte foot processes and a thickening of the basal lamina. Renin immunostaining and kidney renin content in the hydronephrotic organ correspond to those in control kidneys. In addition, renin release from this preparation can be stimulated in a typical manner by isoproterenol and inhibited by angiotensin II, indicating that the receptors controling renin release and the secretory mechanism itself are still intact. Electrophysiological recordings from JG and VSM cells show a high membrane potential (-75 mv), and spontaneous depolarizing junction potentials, owing to transmitter release from the nerve terminals. Inhibitors of renin secretion, e.g. angiotensin II, depolarize both cell types, whereas stimulators such as isoproterenol do not change the membrane potential. We conclude that the hydronephrotic mouse kidney is a suitable model for in vitro studies of the electrophysiology and biochemistry of the media cells of the afferent arteriole, as well as for in vivo studies of glomerular microcirculation.

Animals↗