Sulfotransferases of two specificities function in the reconstitution of high endothelial cell ligands for L-selectin.

L-selectin, a lectin-like receptor, mediates rolling of lymphocytes on high endothelial venules (HEVs) in secondary lymphoid organs by interacting with HEV ligands. These ligands consist of a complex of sialomucins, candidates for which are glycosylation- dependent cell adhesion molecule 1 (GlyCAM-1), CD34, and podocalyxin. The ligands must be sialylated, fucosylated, and sulfated for optimal recognition by L-selectin. Our previous structural characterization of GlyCAM-1 has demonstrated two sulfation modifications, Gal-6-sulfate and GlcNAc-6-sulfate in the context of sialyl Lewis x. We now report the cloning of a Gal-6-sulfotransferase and a GlcNAc-6-sulfotransferase, which can modify GlyCAM-1 and CD34. The Gal-6-sulfotransferase shows a wide tissue distribution. In contrast, the GlcNAc-6-sulfotransferase is highly restricted to HEVs, as revealed by Northern analysis and in situ hybridization. Expression of either enzyme in Chinese hamster ovary cells, along with CD34 and fucosyltransferase VII, results in ligand activity, as detected by binding of an L-selectin/IgM chimera. When coexpressed, the two sulfotransferases synergize to produce strongly enhanced chimera binding.

En bloc resection of abdominal aorta and paraaortic lymph node metastasis of sigmoid cancer.

The surgical management of colorectal metastasis is becoming a widespread practice in oncology. Synchronous resection of metastasis together with invaded major vessels (aorta) is still considered an extremely aggressive procedure. We demonstrate that en bloc resection of invaded aorta and paraaortic lymph node metastasis can be safely performed. The literature from experiences with similar techniques is also discussed.

Determination of aortic distensibility and its variations in arterial hypertension.

Aortic distensibility has been determined by non-invasive techniques: radioisotope measurement, quantitative radiocardiography and indirect arterial pressure measurement with calculation of the aortic rigidity index by the formula D = PP pulse (mm or mercury) / stroke volume (ml). The index value, equalling in normotensive subjects D = 0.55 was quite close to the value obtained in haemodynamic laboratories by invasive techniques (intracardiac stroke volume and arterial pressure measurements). Using the hereby determined aortic is rigidity index by non-invasive techniques, it was established that aortic distensibility is reduced since the early phases of arterial hypertension and in early age. Lowering of aortic distensibility correlates very well with diastolic pressure rise and with advancing age of patients with arterial hypertension. The aortic rigidity index, determined by non-invasive techniques, in suggested as an additional diagnostic and prognostic criterion in arterial hypertension.

Content of prostaglandins E and F in the blood plasma and kidneys in arterial hypertension (clinical-experimental study).

A dynamic study is made of the content of PGE and PGF2 alpha in the kidneys of rats with experimental coarctation hypertension, as well as the PGF2 alpha-metabolite in the blood plasma of the same experimental model in rats and in patients with arterial hypertension. The level of the PGF2 alpha-metabolite tends to decrease both in the animals with experimental hypertension and in hypertonic patients. In rats with 30-day hypertension low values are established in 55 per cent, while in 45 per cent there are high values of the PGE level in the kidney homogenate compared with the control group. The concentration of PGF2 alpha in the left ("endocrine") kidney (whose artery originates distally from the place of aortic coarctation) is higher than the concentration of the same PG in the right kidney. Our findings give grounds for the following assumptions: 1. The PGF2 alpha-metabolite as hormone and partly PGE in the kidneys seem to be involved in the pathogenesis of arterial hypertension as compensatory factors. 2. PGF2 alpha in the kidneys probably participates directly as one of the elements of the complex pathogenesis of arterial hypertension.

Chiral aminophosphonate eluent for enantiomeric analysis of amino acids.

An aqueous solution of the (+)-monoethyl ester of N-(1'-hydroxymethyl)propyl-alpha-aminobenzylphosphonic acid has been proposed as a suitable chiral eluent for enantiomeric analysis of amino acids by ligand-exchange chromatography. Asymmetric synthesis of the chiral selector using (-)-(R)-2-aminobutan-1-ol as a starting reactant is described. The dependence of the parameters of separation of valine enantiomers on concentration of the complexing ion, pH, and temperature has been investigated. It is shown that the order in which enantiomers are eluted from a column depends on the concentration of the complexing ion and pH.