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2.
Eur J Biochem ; 261(3): 629-39, 1999 May.
Article in English | MEDLINE | ID: mdl-10215878

ABSTRACT

The lipopolysaccharides (LPS) from Escherichia coli rough mutant strains F470 (R1 core type) and F576 (R2 core type) were deacylated yielding in each case a mixture of oligosaccharides with one predominant product which was isolated using high-performance anion-exchange chromatography. In addition, one oligosaccharide present in minor quantities was isolated from LPS of E. coli strain F576 (R2 core type). The structures of the oligosaccharides were determined by chemical analyses and NMR spectroscopic experiments. Furthermore, de-O-acylated and dephosphorylated LPS preparations were investigated by fast-atom bombardment and collision induced dissociation tandem mass spectrometry. The combined data allow us to deduce the following carbohydrate backbones of the E. coli R1 and R2 core types which share the following structure (Scheme 1): but differ in the substituents R1 and R2 which for the R1 core type are predominantly: and to a minor extent: and for the R2 core type predominantly: and to a minor extent: in which all sugars are d-pyranoses (l,d-Hep, lglycerodmanno-heptopyranose; P, phosphate).


Subject(s)
Escherichia coli/chemistry , Lipopolysaccharides/chemistry , Carbohydrate Conformation , Carbohydrate Sequence , Escherichia coli/genetics , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Mutation , Spectrometry, Mass, Fast Atom Bombardment
3.
Bioorg Khim ; 24(1): 16-20, 1998 Jan.
Article in Russian | MEDLINE | ID: mdl-9551196

ABSTRACT

The synthesis of novel nucleotide analogues on the basis of ethylphosphonic acid was described. A rigid structural element, an amide or a double bond, was characteristics of the compounds synthesized. The antiviral and cytotoxic activities of these compounds were studied in cell cultures.


Subject(s)
Antiviral Agents/pharmacology , Nucleotides/chemical synthesis , Organophosphonates/chemistry , Amides , Animals , Cells, Cultured , Chlorocebus aethiops , Cytomegalovirus/drug effects , HeLa Cells , Herpesvirus 3, Human/drug effects , Humans , Magnetic Resonance Spectroscopy , Nucleotides/pharmacology , Oximes , Stereoisomerism , Structure-Activity Relationship , Vero Cells
4.
Eur J Biochem ; 247(1): 82-90, 1997 Jul 01.
Article in English | MEDLINE | ID: mdl-9249012

ABSTRACT

The structure of the lipopolysaccharide (LPS) from Acinetobacter haemolyticus strain NCTC 10305 (DNA group 4) was elucidated by means of analytical chemistry, NMR spectroscopy and fast-atom-bombardment mass spectrometry. Several oligosaccharides were obtained after deacylation or successive de-O-acylation, dephosphorylation, reduction, and de-N-acylation of LPS. In the major fraction of the LPS, the core is attached to the lipid A through D-glycero-D-talo-2-octulopyranosonic acid (Ko), whereas in a minor fraction (<20%) Ko is replaced by 3-deoxy-D-manno-octulopyranosonic acid (Kdo). The structures of the phosphorylated carbohydrate backbones of these LPS fractions are [structure: see text] with Dha = 3-deoxy-D-lyxo-2-heptulosaric acid, Sug = sugar and is Ko in a major fraction and Kdo in a minor fraction. All sugar residues have the D-configuration and are present in the pyranose form. Mass spectrometry of de-O-acylated LPS revealed the presence of an additional hexose residue in minor amounts, the position and nature of which could not be identified.


Subject(s)
Acinetobacter/chemistry , Lipopolysaccharides/chemistry , Mass Spectrometry , Oligosaccharides/analysis
5.
Carbohydr Res ; 299(1-2): 69-76, 1997 Mar 26.
Article in English | MEDLINE | ID: mdl-9129296

ABSTRACT

A capsular polysaccharide was obtained from Alteromonas nigrifaciens IAM 13010T by saline extraction. On the basis of 1H and 13C NMR spectroscopy, including one-dimensional (1D) NOE spectroscopy, 2D rotating-frame NOE spectroscopy (ROESY), and 1H-detected heteronuclear 1H,13C multiple-quantum coherence (HMQC), it was concluded that the polysaccharide contained inter alia an acidic sugar, 3-deoxy-D-manno-octulosonic acid (Kdo), and a rare amino sugar, 2-acetamido-2,6-dideoxy-L-talose (L-6dTalNAc, N-acetylpneumosamine), and has a pentasaccharide repeating unit of the following structure: [equation: see text]


Subject(s)
Gram-Negative Aerobic Bacteria/immunology , Hexosamines/analysis , Polysaccharides, Bacterial/chemistry , Carbohydrate Conformation , Carbohydrate Sequence , Gram-Negative Aerobic Bacteria/chemistry , Gram-Negative Aerobic Bacteria/growth & development , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Oligosaccharides/chemistry , Oligosaccharides/isolation & purification , Polysaccharides, Bacterial/isolation & purification , Sugar Acids/analysis
6.
Izv Akad Nauk Ser Biol ; (6): 749-53, 1996.
Article in Russian | MEDLINE | ID: mdl-9044681

ABSTRACT

Interaction between phosphorus amino acids analogs, 1-aminoalkylphosphonous and 1-aminoalkylthiophosphonic acids, and microsomes from the liver of phenobarbital-induced rabbits was studied. The phosphorus amino acids analogs cause type I and reverse type I spectral changes, respectively. A new reaction in the microsomal monooxygenase system was revealed. In the presence of NADPH, 1-aminoalkylphosphonous acids can be transformed to the corresponding 1-aminoalkylphosphonic acids by the reaction P-H-->P-OH. The reaction was monitored by 1H-NMR spectroscopy. 1-Aminoalkylphosphonous acids also serve as substrates for the NADPH-dependent monooxygenase system. 31P-NMR has shown that the oxidative desulfuration produces 1-aminoalkylphosphonous acids according to the reaction P=S-->P=O. Neither 1-aminoalkylphosphonous nor 1-aminoalkylphosphonic acids are deaminated in the NADPH-dependent monooxygenase system as follows from 1H-NMR spectroscopy.


Subject(s)
Amino Acids/metabolism , Aryl Hydrocarbon Hydroxylases , Cytochrome P-450 Enzyme System/metabolism , Organophosphorus Compounds/metabolism , Steroid Hydroxylases/metabolism , Absorption , Animals , Cytochrome P-450 Enzyme System/biosynthesis , Cytochrome P-450 Enzyme System/drug effects , Drug Interactions , Enzyme Induction/drug effects , Magnetic Resonance Spectroscopy , Male , Microsomes, Liver/drug effects , Microsomes, Liver/enzymology , NADP/metabolism , Phenobarbital/pharmacology , Rabbits , Spectrum Analysis , Steroid Hydroxylases/biosynthesis , Steroid Hydroxylases/drug effects , Substrate Specificity/drug effects
7.
Xenobiotica ; 25(3): 219-27, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7618348

ABSTRACT

1. This study deals with the oxidation of organophosphorus amino acid analogues by phenobarbital-induced rabbit liver microsomes. It has been shown that 1-aminoalkylphosphonous and 1-aminoalkylthiophosphonic acids are converted by P450 to 1-aminoalkylphosphonic acids. 2. Phosphonous analogues of amino acids cause type I spectral changes, and thiophosphonic analogues produce reverse type I changes in different spectra. 3. In the presence of NADPH, the 1-aminoalkylphosphonous acids form the corresponding 1-aminoalkylphosphonic acids by the reaction P-H-->P-OH, as monitored using 1H nmr spectroscopy. 4. Aminoalkylthiophosphonic acids have also proven to be the substrates for the NADPH-dependent monoxygenase system. During the course of oxidative desulphuration 1-aminoalkylphosphonic acids were formed by the reaction P = S-->P = O, as monitored by 31P-nmr spectroscopy. 5. Using resonance Raman (RR) spectroscopy, the interaction of 1-aminoisobutyl-phosphonous acid with P450 was investigated, and characteristic changes in spectral frequencies in the region between 1370 and 1700 cm-1 were demonstrated. These latter changes indicate that substrate binding of organophosphorus compounds leads to alterations in haem conformation and to redistribution of the electron density.


Subject(s)
Amino Acids/metabolism , Cytochrome P-450 Enzyme System/metabolism , Microsomes, Liver/enzymology , Organophosphorus Compounds/metabolism , Animals , Magnetic Resonance Spectroscopy , Male , Microsomes, Liver/drug effects , Models, Molecular , NADP/pharmacology , Organophosphonates/metabolism , Phenobarbital/pharmacology , Phosphorus Acids/metabolism , Rabbits , Spectrum Analysis, Raman , Substrate Specificity
8.
Phys Rev D Part Fields ; 47(11): 5018-5020, 1993 Jun 01.
Article in English | MEDLINE | ID: mdl-10015511
9.
Phys Rev D Part Fields ; 44(7): R1903-R1904, 1991 Oct 01.
Article in English | MEDLINE | ID: mdl-10014103
10.
Phys Rev D Part Fields ; 42(5): 1863-1867, 1990 Sep 01.
Article in English | MEDLINE | ID: mdl-10013034
11.
Phys Rev D Part Fields ; 33(3): 852-855, 1986 Feb 01.
Article in English | MEDLINE | ID: mdl-9956704
12.
Phys Rev D Part Fields ; 32(5): 1186-1197, 1985 Sep 01.
Article in English | MEDLINE | ID: mdl-9956264
13.
Phys Rev D Part Fields ; 31(5): 1119-1126, 1985 Mar 01.
Article in English | MEDLINE | ID: mdl-9955805
14.
Radiology ; 153(2): 545-6, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6484186

ABSTRACT

Optimal opacification of the small bowel is important in the interpretation of abdominal CT. Two contrast agents, a barium suspension and an iodinated, water-soluble material, were evaluated in a blind prospective study of 54 patients. A grading system of small bowel opacification was developed. There was no significant difference between the two agents in opacification of the small bowel.


Subject(s)
Diatrizoate Meglumine/administration & dosage , Diatrizoate/analogs & derivatives , Intestine, Small/diagnostic imaging , Tomography, X-Ray Computed , Humans , Radiography, Abdominal
15.
J Comput Assist Tomogr ; 6(3): 497-501, 1982 Jun.
Article in English | MEDLINE | ID: mdl-7096695

ABSTRACT

The initial clinical presentation of intraabdominal disease can be in an extraabdominal location. This phenomenon most commonly occurs in the setting of bowel perforation secondary to diverticulitis, appendicitis, or carcinoma, with resultant spread of infection caudal to the abdomen. Hematomas and pancreatic fluid collections may also dissect out of the abdomen. The spread of these disease processes is likely to occur in a predictable fashion along anatomic tissue planes. Computed tomography (CT) is well suited to demonstrate the extraabdominal site of disease, the pathway of spread from the abdomen, and the occult intraabdominal process. We describe four such cases in which CT was useful and discuss the anatomic pathways involved.


Subject(s)
Radiography, Abdominal , Tomography, X-Ray Computed , Abscess/diagnostic imaging , Adult , Aged , Aorta, Abdominal/surgery , Bacterial Infections/diagnostic imaging , Blood Vessel Prosthesis/adverse effects , Cellulitis/diagnostic imaging , Colonic Diseases/complications , Crohn Disease/complications , Female , Fistula/complications , Hip Joint , Humans , Intestinal Perforation/complications , Leg , Male , Middle Aged , Muscular Diseases/diagnostic imaging , Pain , Pelvis , Pregnancy
16.
Vet Med Nauki ; 18(1): 61-9, 1981.
Article in Bulgarian | MEDLINE | ID: mdl-7303478

ABSTRACT

A comparative study was carried out on the immunologic and antigenic properties of 8 strains of Babesia ovis isolated in 5 districts of the country. The immunologic capacity was tested through challenging with each of the strains in group of 4 weaned lambs that were preliminary vaccinated with one of the strains - Veliko Turnovo. Two nonvaccinated animals were included in each group, serving as controls. The strength of immunity was checked by both the temperature and the parasitic reaction as well as through the hematocrit and hemoglobin levels of the challenged lambs. With the exception of one spleen - ectomized animal in each group the vaccinated weaned lambs showed solid immunity against both the homogeneous and heterologic strains. The same result was confirmed also with an analogous biologic experiment with a total of 19870 sheep in 28 enzootic foci in the same 5 districts and in 2 other districts of the country. Cross serologic investigations by means of the complement - fixation test, the agar gel precipitation reaction and IRPA with homologous and heterologous antisera revealed identic or close antigenic properties in the tested strains. In is concluded that the Veliko Turnovo strain can be used to prepare a vaccine for the immunoprophylaxis of babesiasis in sheep in the investigated districts. In is also stated that the serologic reactions, and, more specifically, IRPA can be employed in the antigenic study and differentiation of individual Babesia ovis strains.


Subject(s)
Antigens/analysis , Babesia/immunology , Animals , Antigens/immunology , Babesiosis/prevention & control , Bulgaria , Cross Reactions , Sheep , Sheep Diseases/prevention & control , Vaccines/immunology
17.
AJR Am J Roentgenol ; 135(4): 878, 1980 Oct.
Article in English | MEDLINE | ID: mdl-6778138
18.
Vet Med Nauki ; 15(4): 72-8, 1978.
Article in Bulgarian | MEDLINE | ID: mdl-105459

ABSTRACT

A total of 395 wild animals represented by 12 species have been studied over the 1972-1975 period for the presence of sarcosporidia--wild swine, does, hares, jackals, foxes, wild cats, polecats, rats, forest mice, and weasels killed in various regions of the district of Bourgas. Investigated were also several monkeys and wandering dogs. Samples were taken from the muscles of the neck abdomen, hind legs, gut, pharynx, chewing muscles, and hearts to study them for microcysts by the compression method. Sarcosporidia were established in 26.08% of the investigated animals of the following species: wild swine--66.76%, does--71.74%, hares--7.28%, rats--5.50%, and forest mice--10.0%. Most intensive proved parasitizing in does, hares, and swine, and least intensive--in rats and mice. Sarcocysts were found in all investigated viscera, highest being the parasite burden in the heart muscle of a doe. The sarcocyst (microcyst) infection in a particular animal species could be established through investigating the muscles of several organs. All data obtained are given in two tables.


Subject(s)
Animal Population Groups/microbiology , Animals, Wild/microbiology , Sarcocystis/isolation & purification , Animals , Bulgaria , Female , Male , Sarcocystosis/epidemiology
19.
Vet Med Nauki ; 13(6): 72-8, 1976.
Article in Bulgarian | MEDLINE | ID: mdl-827846

ABSTRACT

Studied were with a naked eye a total of 8185 carcasses of adult sheep and weaned lambs slaughtered at the abattoirs of Bourgas and Yambol at the age of one year as well as 1783 heads, 1054 hearts, and 468 gullets of weaned lambs for the presence of macroscopically seen sarcocysts. The animals originated from more than 50 communities in the districts of Bourgas and Yambol. The parasite burden was investigated in 1291 sheep carcasses (without heads and viscera). The percent of animals infected with sarcocysts was found to be 95.75 (carcasses) and 63.10 (heads). N cysts were established in the heart muscle. 56.98 per cent of the sheep carcasses were infected with one to 10 cysts, 36.55 per cent - with 11 to 50 cysts, 4.86 per cent - with 51 to 100, 1.17 per cent - with 101 to 200 cysts, and 0.16 per cent - with more than 200 cysts. It was found that the greater part of the sheep carcasses presented sarcocysts both on the outer and on the inner (abdomen and thorax) surface. The parasite burden was more substantial inside the carcasses. Cysts were likewise observed throughout the carcasses, showing no strict localization. Weaned lambs slaughtered at the age of up to one year presented no sarcocysts seen with a naked eye. The necessity is stressed of more strict regulations of meat inspection, resp., hygiene evaluation of carcasses with view establishing sarcosporidia.


Subject(s)
Sarcocystosis/epidemiology , Sheep Diseases/epidemiology , Animals , Bulgaria , Food Inspection , Meat , Sarcocystis , Sarcocystosis/pathology , Sheep
20.
Vet Med Nauki ; 12(5): 55-61, 1975.
Article in Bulgarian | MEDLINE | ID: mdl-813365

ABSTRACT

A total of 458 cows, oxen, and calves (up to the second year of age) were studied over the 1971-1973 period. The animals were slaughtered at the abattoir of the town of Bourgas, originating from 59 communities on the territory of Bourgas district where the field and feeding conditions varied. Samples were taken from the gullet, tongue, pharynx, diaphragm, cervical muscles, and heart, using the compression slide method to demonstrate the presence of microcysts. Sarcosporidia were found in 398 animals as follows: cows and oxen involved--99.11 per cent; calves--75.53 per cent. The average value for the whole group was 86.89 per cent. Lowest were the cases of parasitic infection in calves that were raised indoors, with lowest parasite burden in the animals involved. On the other hand, highest microcyst burden was found in calves that had been kept in mountainous grasslands. No differences were found in the extent of parasite infection between the animals of the two sexes. More severe was the infection in animals in the individual microregions (communities) and the mountainous region as a whole, and it was lowest in animals in the plain region of the district. Both the percentage of animals involved and the parasite burden showed year-to-year variations. Microcysts were observed in all investigated organs. The heart muscle was most frequently involved in all affected animals, showing also highest parasite burden. Lowest were the values concerning the skeletal musculature (cervical muscles). The data of the investigation are given in three tables.


Subject(s)
Cattle Diseases/epidemiology , Sarcocystosis/veterinary , Age Factors , Animal Husbandry , Animals , Bulgaria , Cattle , Cervix Uteri/parasitology , Diaphragm/parasitology , Esophagus/parasitology , Female , Heart/parasitology , Male , Pharynx/parasitology , Sarcocystis/isolation & purification , Sarcocystosis/epidemiology , Sex Factors , Tongue/parasitology
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