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Biomedical subjects

S Kaya

Publications and source records attributed to S Kaya.

At least 109 records · Page 6Linked to original sources

Biosynthesis of linkage units for teichoic acids in gram-positive bacteria: distribution of related enzymes and their specificities for UDP-sugars and lipid-linked intermediates.

The distribution and substrate specificities of enzymes involved in the formation of linkage units which contain N-acetylglucosamine (GlcNAc) and N-acetylmannosamine (ManNAc) or glucose and join teichoic acid chains to peptidoglycan were studied among membrane systems obtained from the following two groups of gram-positive bacteria: group A, including Bacillus subtilis, Bacillus licheniformis, Bacillus pumilus, Staphylococcus aureus, and Lactobacillus plantarum; group B, Bacillus coagulans. All the membrane preparations tested catalyzed the synthesis of N-acetylglucosaminyl pyrophosphorylpolyprenol (GlcNAc-PP-polyprenol). The enzymes transferring glycosyl residues to GlcNAc-PP-polyprenol were specific to either UDP-ManNAc (group A strains) or UDP-glucose (group B strains). In the synthesis of the disaccharide-bound lipids, GlcNAc-PP-dolichol could substitute for GlcNAc-PP-undecaprenol. ManNAc-GlcNAc-PP-undecaprenol, ManNAc-GlcNAc-PP-dolichol, Glc-GlcNAc-PP-undecaprenol, Glc-GlcNAc-PP-dolichol, and GlcNAc-GlcNAc-PP-undecaprenol were more or less efficiently converted to glycerol phosphate-containing lipid intermediates and polymers in the membrane systems of B. subtilis W23 and B. coagulans AHU 1366. However, GlcNAc-GlcNAc-PP-dolichol could not serve as an intermediate in either of these membrane systems. Further studies on the exchangeability of ManNAc-GlcNAc-PP-undecaprenol and Glc-GlcNAc-PP-undecaprenol revealed that in the membrane systems of S. aureus strains and other B. coagulans strains both disaccharide-inked lipids served almost equally as intermediates in the synthesis of polymers. In the membrane systems of other B. subtilis strains as well as B. licheniformis and B. pumilus strains, however, the replacement of ManNAc-GlcNAc-PP-undecaprenol by Glc-GlcNAc-PP-undecaprenol led to a great accumulation of (glycerol phosphate)-Glc-GlcNAc-PP-undecaprenol accompanied by a decrease in the formation of polymers.

Carbon Radioisotopes↗

Surgical treatment of hydatid cysts of the lung: report on 1055 patients.

Of 1055 patients treated surgically for pulmonary hydatid disease, most (950) had isolated lung cysts, the other 105 having both liver and lung cysts. The chest radiograph was most valuable in diagnosis; the Casoni and Weinberg tests and blood eosinophil counts were found to be diagnostically unreliable. One thousand and seventy seven primary operations were performed. Cystotomy and capitonnage were carried out in 906 patients, 40 of whom also had decortication of the pleura. Other procedures included cystotomy with wedge resection of locally damaged lung (29 patients) and cyst removal with capitonnage by Ugon's method (33) or the Perez-Fontana procedure (8) and with costal resection for osteomyelitis in two cases. More radical surgery was carried out in 99 patients for longstanding infection or severe lung destruction. Postoperative complications occurred in 37 patients (3.5%) and the 30 day mortality rate was 1.7%. It is concluded that a lung conserving surgical operation is the treatment of choice for most patients with pulmonary hydatid disease. In patients with coexisting liver cysts the thoracic transpleural approach allowed the lung and liver cysts to be removed at the same session.

Adolescent↗

Pyruvic-acid-containing polysaccharide in the cell wall of Bacillus polymyxa AHU 1385.

Three acidic polymer fractions with molecular masses of about 16 kDa, 35 kDa and 70 kDa were isolated from lysozyme digests of N-acetylated cell walls of Bacillus polymyxa AHU 1385 by ion-exchange chromatography and gel chromatography. These fractions, containing mannosamine, glucosamine and pyruvic acid in a molar ratio of about 1:1:1 together with glycopeptide components, were characterized as polysaccharide-linked glycopeptides with one, two and more polysaccharide chains. On the other hand, treatment of the cell walls with glycine/HC1 buffer, pH 2.5, at 100 degrees C for 10 min followed by separation of water-soluble products on ion-exchange chromatography gave three polysaccharide fractions, PS-I-III, which contained different amounts of pyruvic acid (0,0.6 and 0.9 residue/mannosamine residue) along with equimolar amounts of mannosamine and glucosamine. Pyruvate-free polysaccharides similar to PS-I were also obtained from PS-II, PS-III and polysaccharide-linked glycopeptides by treatment with 10 mM HC1 at 100 degrees C for 1 h. Results of analyses of these polysaccharide preparations by 1H-NMR and 13C-NMR measurement and methylation, together with data from characterization of fragments obtained by hydrogen fluoride hydrolysis, lead to the most likely structure, ----3)[4,6-O-(1-carboxyethylidene)]ManNAc(beta 1----4)GlcNac(beta 1----, for the acidic polysaccharide of this strain.

Acetylglucosamine↗

Surgical treatment of bilateral hydatid disease of the lung via median sternotomy: experience in 60 consecutive patients.

Sixty patients who underwent operation between 1979-1987 for bilateral pulmonary hydatid disease using median sternotomy approach are reported on. Although some authors prefer two-stage thoracotomy and operate on the side with the larger cyst first, or perform simultaneous bilateral thoracotomies, we have preferred one-stage operation via median sternotomy. There were 29 female and 31 male patients, ranging in age from 5 to 55 years (mean 26.4 +/- 6.3). A total of 173 cysts were operated in 120 lungs. The usual operative technique was cystotomy and capitonnage. Operative and postoperative courses were uneventful in all but three cases (5%). The causes of mortality in these patients were excessive hemorrhage, mediastinitis, and septic shock respectively. It is concluded that median sternotomy is a better alternative method for the treatment of bilateral hydatid disease of the lung, as the duration of hospitalisation is shorter, the approach is better tolerated by the patients than thoracotomy, and it possibly prevents a second general anesthesia.

Adolescent↗

Surgical treatment of childhood pleural empyema.

From June 1977 to January 1987, 175 patients underwent surgical treatment of childhood pleural empyema. The surgical treatment consisted of tube drainage in 159 (90%) cases, decortication in 31 (17%) cases, pleuropneumonectomy in 2, lobectomy in 1, and partial thoracoplasty in one cases. There were 2 hospital deaths (14 and 26 days after admission). Late recurrences didn't occur, except in one case where a partial thoracoplasty was necessary. During the follow-up of 11 to 120 months (mean 32 months) examinations were done by chest radiographs. We believe that, children with loculated empyema can be treated successfully with antibiotics and chest tube drainage in early stage. The tube drainage is a more effective method than the other surgical procedures. Few patients require open drainage, and further surgery is rarely required.

Adolescent↗

Structure of the O-polysaccharide chain of lipopolysaccharide from Pseudomonas aeruginosa IID 1001 (ATCC 27577).

Structural studies were carried out on an acidic O-polysaccharide released by mild acid treatment from the lipopolysaccharide of Pseudomonas aeruginosa IID 1001 (ATCC 27577), which is serologically related to the serotypes Habs O3, Lanyi O1, and Wokatsch O13 in other serological classifications of Pseudomonas aeruginosa. The composition and data from structural analyses including H-NMR and C-NMR measurements, methylation, and Smith degradation showed that the structure of the IID 1001 O-polysaccharide was coincident with that of the Habs O3 and Lanyi O1 antigens (or Wokatsch O13). However, whereas solvolysis of the O-antigen of Habs O3 as well as that of Lanyi O1 by hydrogen fluoride has been reported to yield a reducing trisaccharide, GlcNAc(alpha 1----4)GalNAcA(alpha 1----3)Bac2NAc4Nacyl (acyl represents a 3-hydroxybutanoyl group), hydrogen fluoride hydrolysis of IID 1001 O-polysaccharide yielded a nonreducing trisaccharide with the reducing terminal bacillosamine residue linked at C-1 to the hydroxyl group of its N-acyl substituent, 3-hydroxybutanoic acid. These results, in combination with mass spectral data, led to the most likely structure for the tetrasaccharide repeating unit of the IID 1001 O-polysaccharide, (formula; see text) in which the location of N-acyl groups on bacillosamine residues differs from that in the O-antigens of Habs O3 and Lanyi O1 (or Wokatsch O13).

Lipopolysaccharides↗

[Surgical treatment of pleural mesothelioma].

Mesothelioma which is the primary tumor of the pleura has recently been subject to many researches because of its poor prognosis and the difficulties met in radical therapy. Between 1974-1986 total 46 patients with pleural mesothelioma were treated surgically at our center. Finally it was concluded that only the cases in stage I and with epithelial malignant pleural mesothelioma should be subjected to radical surgery. The remaining patients should be treated with conservative methods.

Adult↗

[Pulmonary and mediastinal bronchogenic cysts].

Bronchogenic cysts are relatively rare anomalies with a congenital origin resulting in an abnormal branching of the tracheo-bronchial tree. They either develop in the pulmonary parenchyma or in the mediastinal region. Between 1975 and 1987, 21 cases of bronchogenic cysts were operated upon. Eighteen of these cysts had a pulmonary localisation and 3 were mediastinal. Only 8 of these were diagnosed pre-operatively by bronchoscopy. The major reason for delay in diagnosis is persistent or recurrent pulmonary infection. Eight cases were treated by cystectomy, 4 by simple wedge resection, 4 by segmental resection, 3 were extirpated and 2 by lobectomy.

Adolescent↗

Characterization of a polysaccharide component of lipopolysaccharide from Pseudomonas aeruginosa IID 1008 (ATCC 27584) as D-rhamnan.

Structural studies were carried out on a rhamnose-rich polysaccharide isolated from the O-polysaccharide fraction of lipopolysaccharide in Pseudomonas aeruginosa IID 1008 (ATCC 27584) after destruction of the major O-specific chain by alkaline treatment. The isolated polysaccharide contained rhamnose, 3-O-methyl-6-deoxyhexose, glucose, xylose, alanine, galactosamine and phosphorus in a molar ratio of 67:6.9:4.3:2.1:1.1:1.0:4.1. Data from analysis involving Smith degradation, methylation, 1H-NMR spectroscopy and optical rotation measurement showed that the polysaccharide was built up of three moieties, a rhamnan chain composed of about 70 D-rhamnose residues, the core chain and an oligosaccharide chain comprising 3-O-methyl-6-deoxyhexose, xylose, rhamnose and probably glucose. The repeating unit of the rhamnan chain was indicated to have the following structure:----3)D-Rha(alpha 1----3)D-Rha(alpha 1----2)D-Rha(alpha 1----. This structure is identical with that proposed previously for the repeating unit of the side chain of lipopolysaccharide from plant pathogenic bacteria Pseudomonas syringae pv. morsprunorum C28 [Smith, A.R.W., Zamze, S.E., Munro, S.M., Carter, K. J. and Hignett, R.C. (1985) Eur. J. Biochem. 149, 73-78].

Chromatography, Gel↗

Surgical treatment of bronchial adenomas: results of 29 cases and review of the literature.

The low-grade malignant potential of bronchial adenoma has been widely reported in the medical literature. During the past 12 years we have treated 29 patients with this disease, 18 (62%) of whom required conventional lobectomy or pneumonectomy, because most of our cases had come to our center after having inappropriate treatments in other centers and loosing time. In these cases we observed either a total obstruction of a bronchus or a destroyed parenchyma due to recurrent pulmonary infections. For this reason, the number of pulmonary resections is more important than conservative surgical procedures in our center. The other 11 cases (38%) were treated by bronchoplasty or more conservative resectional procedures. There was no recurrence and the survival rate was about 96 per cent at 5 years. We believe that, in our series, we would have mostly been able to perform conservative types of resections if we could have diagnosed the disease in its early stages.

Adenoma↗

Deficiency of peptidoglycan and lipopolysaccharide components in Rickettsia tsutsugamushi.

Analyses of chemical composition in whole cells of Rickettsia tsutsugamushi were performed and compared with those of the other rickettsiae and gram-negative bacteria. The results indicated that R. tsutsugamushi does not contain detectable amounts of 3-deoxy-D-mannooctulosonic acid, heptose, muramic acid, or glucosamine (less than 2, less than 2, less than 3, and less than 3 nmol/mg, respectively). The microorganism was found to contain four kinds of fatty acids (16:0, 18:0, 18:1, and 18:2), but not hydroxy fatty acids. Furthermore, in analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by silver or Coomassie blue staining, lipopolysaccharide bands were not detected in preparations treated with proteinase K. It is concluded that R. tsutsugamushi has little or no peptidoglycan or lipopolysaccharide.

Bacterial Proteins↗

Serum ferroxidase I and II in uremic patients under conservative treatment and maintenance hemodialysis.

Serum ferroxidase I (ceruloplasmin) and ferroxidase II activities were studied in 49 uremic patients under conservative treatment, in 79 patients undergoing hemodialysis and in 56 healthy subjects, as controls. Ferroxidase I was significantly higher in both groups of patients. Ferroxidase II was significantly elevated only in patients undergoing chronic hemodialysis. The cause of this difference is not clear, but seems to be of considerable interest.

Adult↗

The structure of the O-specific chain of lipopolysaccharide from Pseudomonas aeruginosa IID 1008 (ATCC 27584).

Structural studies were carried out on the O-polysaccharide fraction obtained from the lipopolysaccharide of Pseudomonas aeruginosa IID 1008 (ATCC 27584). The O-polysaccharide comprises L-rhamnose, N-acetyl-D-quinovosamine, N-acetyl-D-galactosaminuronic acid, and N-formyl-D-galactosaminuronic acid. The characterization of oligosaccharide fragments resulting from acid hydrolysis, Smith degradation and alkaline degradation of the O-polysaccharide, together with 1H-NMR and 13C-NMR spectroscopic data of the polysaccharide, led to the following structure for the repeating units: ----3)Rha(alpha 1----4)GalNAcA(alpha 1----4 GalNFoA(alpha 1----3)QuiNAc(alpha 1----. Almost all of the carboxyl groups of the N-acetylgalactosaminuronic acid residues and about half of the same groups of the N-formylgalactosaminuronic acid residues were in an amide form.

Antigens, Bacterial↗

Structural studies on the linkage unit between poly(galactosylglycerol phosphate) and peptidoglycan in cell walls of Bacillus coagulans.

Structural studies were carried out on the linkage units in the teichoic-acid--glycopeptide complexes isolated from lysozyme digests of the cell walls of Bacillus coagulans AHU 1366. On treatment with 47% hydrogen fluoride, the complexes gave a disaccharide characterized as glucosyl(beta 1----4)N-acetylglucosamine together with major fragments, galactosyl(alpha 1----2)glycerol. By means of Smith degradation and partial acid hydrolysis, the teichoic acid chain was shown to be composed of the repeating units, galactosyl(alpha 1----2)glycerol-3(1)-phosphate, which were joined by phosphodiester bonds at C-6 of the galactose residues. The mild alkaline hydrolysis of teichoic-acid-linked glycan fragments yielded teichoic acid chains and disaccharide-linked glycan fragments, from which the disaccharide, glucosyl(beta 1----4)N-acetylglucosamine, was liberated by mild acid hydrolysis, whereas the same disaccharide linked to the teichoic acid chain was obtained by direct heating of the cell walls at pH 2.5. In addition, the presence of specialized glycerol phosphate units in the linkage region was shown by the isolation of tris(glycerol phosphate)3-glucosyl(beta 1----4)N-acetylglucosamine from the products of the Smith degradation of the teichoic-acid--glycopeptide complexes. Thus, it is concluded that the poly(galactosylglycerol phosphate) chain in the cell walls of B. coagulans AHU 1366 is linked to peptidoglycan through a novel linkage unit, bis(glycerol phosphate)-3-glucosyl(beta 1----4)N-acetylglucosamine.

Bacillus↗

Characterization of a novel linkage unit between ribitol teichoic acid and peptidoglycan in Listeria monocytogenes cell walls.

The structure of the linkage unit between ribitol teichoic acid and peptidoglycan in the cell walls of Listeria monocytogenes EGD was studied. A teichoic-acid--glycopeptide preparation isolated from lysozyme digests of the cell walls of this strain contained mannosamine, glycerol, glucose and muramic acid 6-phosphate in an approximate molar ratio of 1:1:2:1, together with large amounts of glucosamine and other components of teichoic acid and glycopeptides. A teichoic-acid-linked sugar preparation, obtained by heating the cell walls at pH 2.5, also contained glucosamine, mannosamine, glycerol and glucose in an approximate molar ratio of 25:1:1:2. Part of the glucosamine residues were shown to be involved in the linkage unit. Thus, on mild alkaline hydrolysis, the teichoic-acid-linked sugar preparation gave a disaccharide characterized as N-acetylmannosaminyl(beta 1----4)-N-acetylglucosamine [ManNAc(beta 1----4)GlcNAc] in addition to the ribitol teichoic acid moiety, whereas the teichoic-acid - glycopeptide was separated into disaccharide-linked glycopeptide and the ribitol teichoic acid moiety by the same procedure. Furthermore, Smith degradation of the cell walls gave a characteristic fragment, EtO2-P-Glc(beta 1----3)Glc(beta 1----1/3)Gro-P-ManNAc(beta 1----4)GlcNAc (where EtO2 = 1,2-ethylenediol and Gro = glycerol). The results lead to the conclusion that in the cell walls of this organism, the ribitol teichoic acid chain is linked to peptidoglycan through a novel linkage unit, Glc(beta 1----3)Glc(beta 1----1/3)Gro-P-(3/4)ManNAc-(beta 1----4)GlcNAc.

Cell Wall↗

Measurement of tonsillar blood flow in normal and pathological conditions by the use of the 133Xe clearance technique.

By using the 133Xe clearance technique, we measured the blood flow to the human palatine tonsil in 10 normal volunteers, 11 patients with chronic tonsillitis, and 11 with hypertrophic tonsils. We found that the mean blood flow was 30.08 +/- 5.39 ml/ 100 g per min in normal tonsils, 17.06 +/- 3.72 in chronic tonsillitis and 49.50 +/- 9.30 in hypertrophic tonsils. Our results show a statistically significant decrease in blood flow in chronic tonsillitis (P less than 0.01) and a significant increase in hypertrophic tonsils (P less than 0.01) when compared to the normal controls. The difference between the blood flow in chronic tonsillitis and hypertrophic tonsils was also statistically significant (P less than 0.01). In all three groups studied, no statistically significant difference was observed in the blood flow to the right and left tonsils (P greater than 0.05).

Adolescent↗

Measurement of nasal mucociliary activity in man with 99mTc-labelled resin particles.

The mucociliary activity in normal and pathological nasal mucosa was studied with a gamma camera using 99mTc-labelled resin particles. The mucus flow rate was investigated under physiological conditions in the following groups of subjects: normal, allergic rhinitis, vasomotor rhinitis, primary atrophic rhinitis, and laryngectomized. The mean flow rates obtained were 5.7 +/- 2.2, 1.5 +/- 0.5, 1.9 +/- 0.8, 0.0, and 4.8 +/- 1.9 mm/min respectively. When the results were compared, the differences between the normal and allergic rhinitis groups, and the normal and vasomotor rhinitis groups were statistically significant (p less than 0.05). However, the differences between the normal and laryngectomized groups, and the allergic and vasomotor rhinitis groups were insignificant (p greater than 0.05).

Adolescent↗

N-acetylmannosaminyl(1----4)N-acetylglucosamine, a linkage unit between glycerol teichoic acid and peptidoglycan in cell walls of several Bacillus strains.

The structure of teichoic acid-glycopeptide complexes isolated from lysozyme digests of cell walls of Bacillus subtilis (four strains) and Bacillus licheniformis (one strain) was studied to obtain information on the structural relationship between glycerol teichoic acids and their linkage saccharides. Each preparation of the complexes contained equimolar amounts of muramic acid 6-phosphate and mannosamine in addition to glycopeptide components and glycerol teichoic acid components characteristic of the strain. Upon treatment with 47% hydrogen fluoride, these preparations gave, in common, a hexosamine-containing disaccharide, which was identified as N- acetylmannosaminyl (1----4) N-acetylglucosamine, along with large amounts of glycosylglycerols presumed to be the dephosphorylated repeating units of teichoic acid chains. The glycosylglycerol obtained from each bacterial strain was identified as follows: B. subtilis AHU 1392, glucosyl alpha (1----2)glycerol; B. subtilis AHU 1235, glucosyl beta(1----2) glycerol; B. subtilis AHU 1035 and AHU 1037, glucosyl alpha (1----6)galactosyl alpha (1----1 or 3)glycerol; B. licheniformis AHU 1371, galactosyl alpha (1----2)glycerol. By means of Smith degradation, the galactose residues in the teichoic acid-glycopeptide complexes from B. subtilis AHU 1035 and AHU 1037 and B. licheniformis AHU 1371 were shown to be involved in the backbone chains of the teichoic acid moieties. Thus, the glycerol teichoic acids in the cell walls of five bacterial strains seem to be joined to peptidoglycan through a common linkage disaccharide, N- acetylmannosaminyl (1----4)N-acetylglucosamine, irrespective of the structural diversity in the glycosidic branches and backbone chains.

Acetylglucosamine↗