The interaction of peripheral blood leukocytes with alpha1-acid glycoprotein, its carbohydrate chains and neoglycoconjugates

The interaction of human peripheral blood leukocytes with alpha 1-acid glycoprotein (AGP), its glycoforms as well as neoglyco-conjugates representing carbohydrate chains of AGP or its fragments was studied by flow cytometry. It was shown that the main target cells for AGP as well as for conjugates of its carbohydrate chains with polyacrylamide (PAA) are monocytes and polymorphonuclear leukocytes but not lymphocytes. The interaction of AGP with monocytes and granulocytes are mediated by its carbohydrate chains: the binding of AGP with cells was inhibited by AGP, AGP oligosaccharides as well as conjugates of oligosaccharides and its fragments with PAA. The data obtained show the existence of monocyte (and granulocyte) receptors which interact with complex type sialooligosaccharides of AGP.     

Isolation of bacterial endotoxins from Pseudomonas putida 36 and Escherichia coli (vulgaris)

A prospective analysis of 69 patients who had been treated for nasopharyngeal carcinoma (NPC) by external radiotherapy was carried out. Biopsies from the posterior nasopharynx were performed and analyzed by in situ hybridization using an antisense Epstein-Barr Early RNA (EBER) radio-labelled riboprobe. None of the patients had evidence of disease in the nasopharynx. One patient was found to have nasopharyngeal carcinoma detected only by in situ hybridization. In the subsequent 18-month follow-up of these clinically- and biopsy-negative patients, only one patient developed relapse in the nasopharynx. In situ hybridization is a valuable tool for the detection of NPC and should be routinely available in histopathology laboratories where NPC is regularly diagnosed.     

Relative contribution of endothelial cell and polymorphonuclear neutrophil activation in their interactions in systemic inflammatory response syndrome

OBJECTIVE: To examine the relative contribution of polymorphonuclear neutrophil (PMN) vs endothelial cell (EC) activation on the adherence and subsequent killing of ECs by PMNs. DESIGN: In vitro comparative studies of PMN-EC adherence and cytotoxicity. SETTING: Research laboratory and the surgical intensive care unit of a tertiary-level university hospital. PATIENTS: Patients with systemic inflammatory response syndrome admitted to the surgical intensive care unit and hospitalized preoperative noninfected surgical patients. INTERVENTION: None. METHODS: Polymorphonuclear neutrophils were isolated from 21 healthy volunteers, 22 preoperative patients, and 30 patients from the surgical intensive care unit with systemic inflammatory response syndrome. The PMNs were activated with lipopolysaccharide, 100 ng/mL (Escherichia coli 0111:b4), for 40 minutes at 37 degrees C before the adherence and cytotoxicity assays. Human umbilical vein endothelial monolayers were stimulated with tumor necrosis factor alpha, 25 ng/mL, and interleukin 1 beta, 15 U/mL, for 3 hours. The PMNs or EC cells were labeled with sodium chromate Cr 51 and used in a standard adherence or killing assay as required. RESULTS: Control and preoperative patient PMN treatment with lipopolysaccharide produced a modest increase in adherence. The PMNs from patients with systemic inflammatory response syndrome showed moderately increased human umbilical vein endothelial cell adherence, and this could not be augmented further with lipopolysaccharide stimulation. There was a marked increase in PMN adherence to EC after EC activation in all study groups (P < .001). Similar to the adherence data, human umbilical vein endothelial cell cytotoxicity was significantly increased in all groups after human umbilical vein endothelial cell activation (P < .01) but not after PMN stimulation with lipopolysaccharide. CONCLUSION: These data suggest that stimulation of ECs is far more important in producing increased adherence and cytotoxicity of EC than PMN stimulation with lipopolysaccharide in all study groups. Therapeutic efforts in patients with systemic inflammatory response syndrome should be focused on the EC.     

The prospects for using the genetically engineered surface antigen of the hepatitis B virus (HBsAg) expressed by recombinant poxvirus strains as the basis for vaccines against hepatitis B

The use of a recombinant poxvirus (RPV) strain, expressing HBsAg in the process of reproduction in different bioreactor systems under stationary and bioreactor conditions of cultivation, made it possible to obtain highly purified HBsAg. The identity and purity of HBsAg was confirmed by the analysis of its amino acid composition, SDS electrophoresis in polyacrylamide gel, electron microscopy and high-performance liquid chromatography. Good prospects of the use of RPV-expressed gene engineering HBsAg as the basis vaccines against hepatitis B was demonstrated in 10 experimental batches of vaccine. All batches of the preparation had pronounced immunogenicity and were safe and nontoxic in animal experiments. The ID50 of experimental batches did not exceed 211 ng/ml, which, according to the data of comparative experiments, was lower than, or equal to, corresponding values of analogous foreign commercial preparations, based on plasma or yeast HBsAg.     

Physician judgment in clinical settings: methodological influences and cognitive performance

Understanding the quality of physicians' intuitive judgments is essential in determining the appropriate use of their judgments in medical decision-making (vis-a-vis analytical or actuarial approaches). As part of this process, the quality of physicians' predictions must be assessed because prediction is fundamental to common clinical tasks: determining diagnosis, prognosis, and therapy; establishing monitoring intervals; performing screening and preventive maneuvers. Critical evaluation of predictive capabilities requires an assessment of the components of the prediction process: the data available for prediction, the method used for prediction, and the accuracy of prediction. Although variation in and uncertainty about the underlying data elements are often acknowledged as a source of inaccurate predictions, prediction also can be confounded by both methodological and cognitive limitations. During the past two decades, numerous factors have been recognized that may bias test characteristics (sensitivity and specificity). These same factors may also produce bias in intuitive judgments. The use of cognitive processes to simplify judgment tasks (e.g., the availability and representativeness heuristics) and the presence of certain biases in the judgment process (e.g., ego, regret) may present obstacles to accurate estimation of probabilities by physicians. Limitations on the intuitive use of information (cognitive biases) have been demonstrated in both medical and nonmedical decision-making settings. Recent studies have led to a deepening understanding of the advantages and disadvantages of intuitive and analytical approaches to decision making. Here, many aspects of the basis for this understanding are reviewed.     

Perfection of methodical approaches to designing vaccines against tick-borne encephalitis

Nine female patients with a urethral diverticulum were admitted to our center over a six period: The clinical symptomatology was not specific. The diagnosis has been performed by voiding and retrograde cysto-uretrogram. The surgical treatment consisted in the excision of the diverticula, with the patient in the supine position. No perioperative morbidity was observed.     

Langmuir films from antibodies based on amphiphilic polyelectrolytes

A technique for forming Langmuir films from antibodies based on an amphiphilic polyelectrolyte was developed. The physicochemical and immunochemical properties of the Langmuir films obtained were studied. The interaction of HBsAg with the films was found to be described by a model with one binding site, whereas that of HBsAg with antibodies adsorbed on a polystyrene plate, by a model with a positive cooperativity. The use of the novel Langmuir films from antibodies increases the sensitivity of the immunoenzyme assay.