Cobalamin binding proteins in patients with HIV infection

Abstract: P-Cobalamins have been reported to be decreased in patients with HIV infection. Because of this, we found it of interest to examine both cobalamin-saturated binding proteins (holo-transcobalamin, holo-TC and holo-haptocorrin, holo-HC) and cobalamin unsaturated binding proteins (apo-transcobalamin, apo-TC and apo-haptocorrin, apo-HC). The results are given as range and (median). Eighteen male HIV-infected patients with plasma cobalamins below 200 pmol/1 were studied. We found low concentrations of holo-TC (37–88 (47.5) pmol/1) and holo-HC (64–184 (135.5) pmol/1). The concentration of apo-TC and apo-HC was increased (480–1730 (1025) pmol/1; 70–800 (235) pmol/1). It is concluded that, in HIV-infected patients, low plasma cobalamin does not reflect a low concentration of transcobalamin or haptocorrin. In 20 HIV-infected patients and 31 patients with malignant haematological diseases, the TC isopeptide patterns were determined. In the HIV group, an increased frequency of TC isopeptide X was found and the overall distribution of TC isopeptides was significantly different from the reference population (p < 0.05). There was no difference between the group of patients with malignant haematological diseases and the reference group.     

A Method for Simultaneous Evaluation of Drug-Effects on Excitability and Inotropy in Isolated Cardiac Preparations

Abstract: A method is described which allows determination of the threshold of excitability of electrically stimulated, regularly contracting isolated cardiac preparations. The force of the contraction (CF) is isometrically recorded and serves as feed-back signal indicating effective stimulation. The pulse intensity is decreased monoexponentially as long as contractions are elicited. If the mechanical response does not occur, the pulse intensity is immediately reset to the initial high value and the pulse is delivered with a latency of a few milliseconds. A stimulus intensity just below threshold is recorded as the rectangular pulse threshold (RPT). The method was applied in order to compare the effects of a number of antiarrhythmic drugs including the β-blocker propranolol on the electrical excitability (1/RPT) and on the contractility of guinea pig left atria stimulated at 3 Hz. In general, the drugs depressed excitability and contractility concomitantly. The rank order of potency with respect to the reduction of excitability was: aprindine > propafenone > propranolol > quinidine > mexilitine > lidocaine. The Ca-antagonist verapamil reduced contractile force most powerful but had no effect on excitability. Presumably, RPT reflects sodium-channel function. In conclusion, the described method offers an easily operable test of drug effects on the excitability threshold and the contractility of isolated cardiac preparations.     

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).     

Sonography of the testis and epididymis

Summary. Sonography (ultrasound) is the mainstay for imaging morphologic abnormalities of the scrotum and testis. It is used primarily for determining the location and nature of palpable lesions and to demonstrate clinically occult, nonpalpable lesions. This article describes the state of the art of scrotal sonography. After an initial presentation of the normal sonographic appearance of the testis and epididymis, the diagnostic evaluation of the most common scrotal disorders is described.
Scrotal sonography is characterized by high sensitivity in the detection of intrascrotal abnormalities and is a very good mode for differentiating testicular from paratesticular lesions. However, scrotal sonography is limited in determining whether a focal testicular lesion is benign or malignant. Unsatisfactory results are obtained by conventional sonography in the evaluation of testicular torsion. This gap in the diagnosis of scrotal pathologies is now being reliably filled by colour-coded duplex sonography.     

3D-surface reconstruction of intravascular ultrasound images using personal computer hardware and a motorized catheter control

A system for three-dimensional (3D) presentation of intravascular ultrasound (US) images was designed. A standard hardware configuration based on personal computer equipment was used for acquisition and processing of image data. Pullback imaging with the US catheter was controlled by a specially designed motor assembly and performed either in equidistant 1–10 mm steps or at a constant retraction speed. Curvature of the vessel was documented on biplane digital subtraction angiograms and the US images were arranged according to the vessel shape in the angiograms. 3D reconstruction appears essential for spatial orientation of intravascular US and may be helpful in the planning of vascular interventions for a better appreciation of the extent and morphology of vascular lesions.     

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Historischer Beitrag Reginald Watson-Jones—Pionier und Lehrmeister der traumatologischen Orthopädie

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