Comparative study of the changes in microanatomical organization of lymph nodes located and functioning in the area of venous congestion

By the morphometric method the microanatomical organization of the popliteal and kidney lymph nodes of the type Vi was studied in venous congestion. In the first experimental series (lymph nodes localize in venous congestion area) the venous congestion in the popliteal lymph nodes was created by the ligature of caudal vena cava. In the second experimental series (lymph nodes, which clean the venous congestion area--the kidney vena was tied up. The small and short time increase of the marginal sinus volume and hypertrophy of the medullary cords, which seemed about medullary substance B-zone stimulation were characteristically for the lymph nodes, localize in the venous congestion area. The sharp increase of the marginal sinus volume during the long experimental time and paracortical T-zone hyperplasia were characteristically for the lymph nodes, which clean the venous congestion area.     

Solid-phase synthesis of peptides with C-terminal asparagine or glutamine. An effective, mild procedure based on N alpha-fluorenylmethyloxycarbonyl (Fmoc) protection and side-chain anchoring to a tris(alkoxy)benzylamide (PAL) handle

Attempts to anchor Fmoc-asparagine or glutamine as p-alkoxybenzyl esters for solid-phase peptide synthesis are fraught with difficulties. A convenient and effective method to prepare peptides with C-terminal asparagine or glutamine involves quantitative attachment of N alpha-Fmoc-C alpha-tert.-butyl aspartate or glutamate via the free omega-carboxyl groups to a tris(alkoxy)benzylamino (PAL) support. Chain elongation proceeds normally by standard Fmoc chemistry, and treatment with acid, e.g., CF3COOH--CH2Cl2, 90 min at 25 degrees, releases the desired peptides in greater than 95% yields without side reactions at the C-terminus. Feasibility of the approach has been demonstrated by the syntheses of the C-terminal octapeptide from human proinsulin, H-Leu-Ala-Leu-Glu-Gly-Ser-Leu-Gln-OH, and the serum thymic factor pGlu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn-OH.     

Purification and partial characterization of an iron regulated outer membrane protein of B. fragilis under non-denaturing conditions

The CHAPS-PAGE gelsystem we applied gave a good separation of the proteins of Bacteroides fragilis under non-denaturing conditions. We succeeded with preparative CHAPS-PAGE in purifying an iron regulated outer membrane protein (a 44 kDa polypeptide on SDS-PAGE) of B. fragilis. This integral membrane protein proved to be a lipopolysaccharide binding protein with an isoelectric point of approximately pH 5.5. This method of purifying membrane proteins could be an important step in research into the function of membrane proteins.     

Protein factors that bind to the murine 2',5'-oligoadenylate synthetase ME-12 gene 5' upstream regulatory region

The murine 2',5'-oligoadenylate synthetase ME-12 gene regulatory region AB forms six complexes with protein factors in murine BALB/c 3T3 cells as demonstrated by the mobility shift electrophoresis assay under the reaction conditions used. The complexes, designated C1-C6 in order of their decreasing electrophoretic mobility, showed three distinctive specificities with regulatory region AB, element A, and element B as probes or competing DNA: 1) C1 is region AB-specific (this complex did not form with either element A or B used alone or as a mixture); 2) C5 formed both with element A and element B; 3) C2, C3, C4, and C6 formed with element B, but not A. The protein factors that give rise to these complexes show differential DNA binding activities in various buffer solutions at different pH values. The C4-forming protein factor is the interferon (IFN)-alpha/beta-stimulated response factor (ISRF) which shows element B specificity. It preexists in the cytoplasm. ISRF appears to be complexed to an inhibitor (ISRFI) in the cytoplasm and to dissociate from the inhibitor and to translocate into the nucleus upon treatment of cells with IFN-alpha/beta. We propose that IFN-alpha/beta treatment of BALB/c 3T3 can trigger at least two events: 1) loosening of a tight inhibitor-ISRF complex with the release of free ISRF; this may be mediated via phosphorylation of ISRF or ISRFI; 2) translocation of ISRF into the nucleus and binding to the enhancer element B, which results in the activation of 2',5'-oligoadenylate synthetase gene expression.     

Experimental bases of endoscopic correction of the secretory function of the stomach

The article gives experimental data proving the usage of the method of bloodless reduction of gastric secretion through endoscope in case of peptic ulcer. Pricking around the secretory zones of the stomach with hypertonic glucose solution conducted on 35 mongrel dogs led to a stable reduction of acid producing function of the stomach. Morphological changes of the stomach mucous membrane were mainly expressed in the atrophy of glands. The analysis of the test results gives opportunity to recommend the clinical introduction of the method in complex treatment of peptic ulcer.     

The indices of antipneumococcal immunity in children with chronic pneumonia

In 76 children with chronic pneumonia the levels of serum antibodies to pneumococcal capsular polysaccharide antigens (serotypes 1, 3, 6B, 8, 9N, 15F, 23F), O-polysaccharide and pneumococcal protein somatic antigens were determined by ELISA techniques. The study showed that in sick children the content of antipneumococcal antibodies in the blood increased with age. No correlation between the content of total immunoglobulins and that of antipneumococcal antibodies in the blood of the patients was established, but a sharp decrease in the concentration of antibodies was registered in a child with hypoglobulinemia. No increase in the level of antibodies to pneumococcal antigens was observed in cases of the exacerbation of Pneumococcus-induced inflammatory process in the lungs.     

The quantitative analysis of lipopolysaccharide antigen in the blood serum of patients with salmonellosis by using complement-bound liposome lysis]

Titration of group B Salmonella O-antigen in the blood sera of patients and donors was carried out by means of the complement-dependent lysis of liposomes sensitized with S. typhimurium LPS. Good correlation (r = 0.95) of the levels of S. typhimurium somatic O-antigen in the patients' sera determined by liposomal immunoassay and aggregate hemagglutination test was established. The concentration of the antigens in the tested samples was within 0.5-50 micrograms/ml. Statistical analysis of the results obtained by liposomal immunoassay techniques demonstrated differences in the distribution functions for the blood sera of patients with different diseases and of donors.     

Sodium cholate-induced changes in the conformation and activity of rat pancreatic cholesterol esterase

Pancreatic cholesterol esterase (CEase) regulates dietary cholesterol absorption and is activated in the presence of trihydroxy bile salts while remaining inactive monohydroxy bile salts. CEase from rat pancreas has been purified by ammonium sulfate precipitation, hydroxylapatite chromatography, and gel filtration on Sephacryl S-200/S-300 columns connected in series, and its homogeneity and Mr (55,418 +/- 288) have been determined by sedimentation equilibrium centrifugation. The effects of tri-, di-, and monohydroxy bile salts on the conformation of the purified enzyme in buffer solution and in an in vitro assay system were studied by circular dichroism spectropolarimetry. The CD spectrum of the enzyme in solution shows a curve shape suggestive of an alpha-helicity, but low mean residue ellipticity (MRE) values may indicate an important beta-turn contribution. Sodium cholate, a trihydroxy bile salt, induces a decrease in the negative MRE values of the enzyme in solution at bile salt concentrations of 70-100 nM, with no further spectral changes at concentrations as high as 1 mM. Sodium cholate concentrations higher than 1 microM also induce an increase in the enzyme's negative MRE values under activity assay conditions, which reverts toward its original value once the reaction reaches equilibrium. These latter changes are interpreted as induced by substrate binding to the enzyme followed by partial substrate depletion after the reaction reaches equilibrium. Sodium deoxycholate, a dihydroxy bile salt, induces unstable transient increases and decreases in the MRE values of CEase in buffer solution and under activity assay conditions. These changes are bile salt concentration-dependent and may reflect self-association of the protein. Sodium taurolithocholate, a monohydroxy bile salt, does not affect the CD spectrum of CEase, and neither the di- or the monohydroxy bile salt activates the enzyme.