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The short-range coordination of Nd(III) and Eu(III) ions in aqueous solutions has been investigated by means of K-edge x-ray absorption spectroscopy. Experimental data are presented which demonstrate that an accurate determination of the Nd(III) and Eu(III) hydration structural parameters can be obtained from the analysis of the K-edge spectra. It is shown that the large widths of the core hole states do not appreciably reduce the potential structural information of the K-edge EXAFS data. In addition the available k-range of the K-edge spectra is much wider compared to that of the L3-edge which is affected by the presence of double-electron excitations in a more severe fashion.

Six hundred laparoscopic cholecystectomies have been performed in patients with cholelithiasis. Co-existing chronic diseases have been noted in 28% of the operated patients. All these diseases have been known to increase operative risk in classic (open) cholecystectomy (hypertension, coronary disease, cardiac arrhythmias, diabetes mellitus, bronchial asthma). Statistical analysis of the body temperature following laparoscopic cholecystectomy, morbidity and duration of the postoperative hospitalization has revealed that there has been no significant increase in operative risk for laparoscopic cholecystectomy in these patients.

The rules of three step therapy of chronic pain in terminal malignant has been presented. The need of priority of non narcotic drugs in retard form, oral or enteral administration and individual schedule out-pacing the occurring of pain has been stressed.

Operational risk of laparoscopic cholecystectomy in elderly patients has been retrospectively evaluated in 600 consecutive patients. Statistical correlation between age and risk factors as: biliary duct disease, adhesions, perforation of the gall bladder, necessity of extending of the incision, duration of the procedure, body temperature after LCh, morbidity, conversion rate from LCh to open cholecystectomy, has been tested. Despite of greater technical difficulties in elderly patients morbidity was not increased significantly. LCh in aged patients with cholecystitis is a safe method of choice.

500 patients with symptomatic biliary stones disease have been treated by laparoscopic cholecystectomy (LCh). Contraindications, such as: acute inflammation, earlier laparotomies, common duct stones or obesity were considered as relatives. In cases with duct stones, ERCP with sphincterotomy and evacuation of duct stones was performed before LCh. Small percentage of LCh failures (2.6%) and of postoperative morbidity (3.4%) by undoubted advantages as: lack of postoperative paresis of digestive tract, reduced inability time for professional activity and low risk of postoperative abdominal hernia make this procedure attractive for patients and surgeons.

A preliminary report on the results of studies on the relationship between alcohol abuse and upper gastrointestinal tumours is presented. Alcohol abuse was measured with the aid of a questionnaire. GGTP and mean MCV were determined. Within the 1st September, 1986--30th September, 1987, 75 patients with the cancer of the upper gastrointestinal tract and 107 patients with benign lesions to this area were examined. Alcohol abuse was found in 33% of patients with the cancer and 19% of patients with benign lesions to the upper gastrointestinal tract. This difference is statistically significant (p greater than 0.05). The results of GGTP and MCV values were statistically insignificant in both groups. The authors have found more marked correlation of alcohol abuse with the cancer of the upper gastrointestinal tract in relation to the oral cavity and pharynx than the stomach. Further studies including larger groups of patients are recommended.

The reports of Miyanohara et al. (1986) and Murphy et al. (1986) were the first to describe the genetic construction, expression, and receptor-specific selective toxicity of a chimaeric toxin. In the present report, we have extended these earlier observations and have shown that the fusion of a modified gene encoding IL-2 to a truncated diphtheria toxin gene also results in the expression of a biologically active chimaeric IL-2 toxin. In both instances we have used receptor-binding-domain substitution and have genetically coupled those portions of the diphtheria toxin structural gene that encode the ADP-ribosyl transferase activity of fragment A and lipid-associating domains of fragment B to modified genes which encode either the polypeptide hormone alpha-MSH or the T-cell growth factor IL-2. The chimaeric toxins expressed from these gene fusions have been shown to be selectively targeted to those eukaryotic cells that carry specific surface receptors for the ligand compounds of the hybrid. For example, in the case of the IL-2 toxin, it is clear that the selective action of this hybrid protein is based upon both its diphtheria-toxin and IL-2-related components. Following binding to the IL-2R on activated and/or malignant T-cell, IL-2 toxin is internalized by receptor-mediated endocytosis. Upon acidification of the endosome, diphtheria toxin fragment B portions of the chimaeric toxin facilitate the delivery of fragment A to the cytosol where it catalyses the ADP ribosylation of EF-2. The assembly of chimaeric toxins at the level of the gene offers several advantages over chemical linkage. Since chemical linkage of the toxophore and ligand components of the conjugate toxins requires activation of the epsilon-amino moiety of lysine residues with reagents that will allow for subsequent disulphide linkage, the precise site of coupling is generally not known. In addition, there has been considerable concern over the lability of the disulphide bond between the toxophore and ligand components in vivo due to the action of disulphide reductases. The assembly of chimaeric toxins at the level of the gene allows for precise linkage of the toxophore and ligand components. Since the linkage between the toxophore and ligand is a peptide bond, the chimaeric toxin should be stable in vivo. In addition, the genetic construction of chimaeric toxins also allows for further protein engineering through site-directed mutagenesis.(ABSTRACT TRUNCATED AT 400 WORDS)

Gamma-carboxyglutamic acid is an amino acid with a dicarboxylic acid side chain. This amino acid, with unique metal binding properties, confers metal binding character to the proteins into which it is incorporated. This amino acid has been discovered in blood coagulation proteins (prothrombin, Factor X, Factor IX, and Factor VII), plasma proteins of unknown function (Protein C, Protein S, and Protein Z), and proteins from calcified tissue (osteocalcin and bone-Gla protein). It has also been observed in renal calculi, atherosclerotic plaque, and the egg chorioallantoic membrane, among other tissues. Gamma-carboxyglutamic acid is synthesized by the post-translational modification of glutamic acid residues. This reaction, catalyzed by a hepatic carboxylase, requires reduced vitamin K, oxygen, and carbon dioxide. The function of gamma-carboxyglutamic acid is uncertain. In prothrombin gamma-carboxyglutamic acid residues bound to metal ions participate as an intramolecular non-covalent bridge to maintain protein conformation. Additionally, these amino acids participate in the calcium-dependent molecular assembly of proteins on membrane surfaces through intermolecular bridges involving gamma-carboxyglutamic acid and metal ions.

A patient with a nodular and diffuse small-cleaved follicular center-cell lymphoma that exhibited definite plasmacytic differentiation, a related monoclonal gammopathy, and circulating population of small lymphocytes is presented. Aside from showing that the presence of numerous plasma cells is not a reliable criterion for the diagnosis of a reactive follicular proliferation, the case is an example of a lymphoma without a block in maturation. The "neoplastic" B-cells show development to follicular center cells and beyond, to functioning plasma cells, and probably also to recirculating "memory" cells. It also suggests that plasmacytoid lymphocytic lymphomas (Lukes-Collins classification) might represent a heterogeneous group of lymphoid neoplasms with some closely related to follicular center-cell lymphomas and others more closely related to small lymphocytic lymphoma/B-cell chronic lymphocytic leukemia.

We have genetically replaced the diphtheria toxin receptor binding domain with a synthetic gene encoding interleukin-2 (IL-2) and a translational stop signal. The diphtheria toxin-related T-cell growth factor fusion gene encodes a 70 586-d polypeptide, pro-IL-2-toxin. The mature form of IL-2-toxin has a deduced mol. wt of 68,086 and is shown to be exported to the periplasmic compartment of Escherichia coli (pABI508), and contain immunologic determinants intrinsic to both its diphtheria toxin and IL-2 components. IL-2-toxin has been purified from periplasmic extracts of recombinant strains of E. coli (pABI508) by immunoaffinity chromatography using immobilized anti-IL-2. The purified chimeric toxin is shown to selectively inhibit protein synthesis in IL-2 receptor bearing targeted cells, whereas cell lines which do not express the IL-2 receptor are resistant to IL-2-toxin action.