[The specific diagnostic features of pulmonary tuberculosis at the lower and middle lobular sites].

Cases of pulmonary tuberculosis at the lower and middle lobular are not so rare. However, there is evidence that there is a rise in the number of patients with lower lobular tuberculosis (0.56-15.1%) of those with pulmonary tuberculosis. The diagnosis of lower lobular tuberculosis presents certain difficulties; it has to be differentiated from multisegmental pneumonia and tumors in some cases. Middle and lower tuberculosis was notified in 4.7% among the first detected patients in the Brest Region in 2003, in 6.8% among the patients with infiltrative pulmonary tuberculosis during 8 months in 2004. Forty-three cases of pulmonary tuberculosis at the above sites were studied in the inpatients of pulmonary tuberculosis departments of the regional tuberculosis dispensary in 2003 and during 6 months in 2004. All these patients were diagnosed as having infiltrative lower lobular tuberculosis that amounted to 5% of infiltrative pulmonary tuberculosis at all sites treated at the hospital. In most cases, there were first diagnosed patients [n = 35 (81.4%)], 8 (18.6%) patients with recurrences. There were 32 (69.8%) males and 11 (25.6%) females; 24 (55.8%) urban dwellers and 19 (44.2%) rural ones. The patients aged over 60 years were predominant [n = 21 (48.8%)], so were pensioners [n = 19 (44.2%)]. Eleven (25.6%) patients had concomitant cardiovascular diseases, 3 (7%) patients had diabetes mellitus; 1 (2.3%) patient had respiratory diseases and one more (2.3%) patient had gastrointestinal diseases; other abnormalities were observed in 11 (25.6%) patients. Most patients [n = 31 (72.1%)] were identified in those seeking medical advice; 12 (27.9%) patients were detected on prophylactic examinations. Thirty-seven (86%) patients had pulmonary and intoxication complaints of varying duration; 6 (14%) patients had no complaints. Due to the untypical acute onset of the disease, 53.5% of this group of patients were admitted to therapeutic and pulmonological departments for suspected pneumonia or other diseases. The efficiency of treatment was as follows: decay cavities were closed in 10 (66.7%) patients; 16 (69.6%) patients stopped isolating Mycobacterium tuberculosis; 7 (16.3%) patients discontinued therapy themselves.

[Bromoacyl analogues of phosphatidylcholine with intramolecular fluorescence quenching and their use as substrates for continuous monitoring of phospholipase A2 activity]. / Bromatsil'nye analogi fosfatidilkholina s vnutrimolekuliarno potushennoi fluorestsentsiei v kachestve substratov dlia nepreryvnoi registratsii aktivnosti fosfolipazy A2.

Two new derivatives of phosphatidylcholine with intramolecular fluorescence quenching were obtained by substituting residues of pyrene butyric and bromine-containing fatty acids for acyl chains. The two compounds can be used for quantitative evaluation of catalytic activity of pancreatic phospholipase A2 in kinetic mode.

[Transformation of phospholipids by cabbage phospholipase D in mixed micelles containing 3-[(3-cholamidopropyl)dimethylammonio]propanesulfonate]. / Transformatsiia fosfolipidov fosfolipazoi D iz kapusty v smeshannykh mitsellakh s 3-[(3-kholamidopropil) dimetilammonio]propansul'fonatom.

We compared the activities of cabbage phospholipase D during hydrolysis and transesterification of phosphatidylcholine in mixed micelles of surface-active compounds with various physicochemical properties. Mixed micelles of phospholipids and 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (ratio, 1:2) were among the best substrates. Hydrolysis and transphosphatidylation were studied in micelles containing 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate. Mixed micelles of phosphatidylcholine and 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate may serve as a new substrate for measurements of phospholipase D activity and preparative isolation of phospholipids using this enzyme.

Radiation-induced fragmentation of cardiolipin in a model membrane.

PURPOSE: To obtain evidence for the possibility of free-radical fragmentation of cardiolipin under the action of ionizing radiation as measured by its aqueous dispersion from liposomes. MATERIALS AND METHODS: Liposomes of tetramyristoylcardiolipin (TMCL) were exposed to gamma-rays from 60Co or 137Cs sources at doses between 1 and 24kGy. Fragmentation products were identified using thin-layer chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). RESULTS: Using MALDI-TOF MS and thin-layer chromatography, it was shown that gamma-irradiation of liposomes consisting of TMCL was accompanied by free-radical fragmentation of the lipid to form dimiristoylphosphatidic acid and dimiristoylphosphatidyl hydroxyacetone. The yields of dimiristoylphosphatidic acid were greater than those of dimiristoylphosphatidyl hydroxyacetone, and formation of the named compounds was inhibited by dissolved oxygen. CONCLUSION: It is shown for the first time that on gamma-irradiation, cardiolipin can undergo free-radical fragmentation in its polar component.

[Effect of phosphatidic acid on the radiation-initiated peroxidation of phosphatidylcholine in liposomes]. / Vliianie fosfatidnoi kisloty na radiatsionno-initsiirovannoe perekisnoe okislenie fosfatidilkholina v liposomakh.

It was found that the incorporation of anionic dipalmitoyl phosphatidic acid (DPPA) into phosphatidylcholine (PC) liposomes up to 15 mol % was accompanied by the intensification of accumulation of diene conjugates (DC), which are primary products of lipid peroxidation (LPO), if the LPO was initiated by gamma-irradiation of a 137Cs source. Monoethyl ester of DPPA, phosphatidylethanol (DPPEt), exerted a lesser influence at the same concentrations. Ca2+ ions inhibited the DC production not only in liposomes consisting of lipid mixture but in lipid membranes of PC alone as well. It was assumed that the electrostatic repulsion of negatively charged DPPA and DPPEt resulted in the loosening of polarside region of membrane hydrophobic layer and in consequence the access of hydroxyl radicals to hydrocarbon chains of PC. This assumption is in good agreement with the results of osmotic behavior of liposomes in hypertonic urea solution.

[Effects of complexes of alpha-fetoprotein and amphiphilic docosaenoic acid derivatives on the humoral immune response in C57BL/6 mice]. / Vliianie kompleksov al'fa-fetoproteina s amfifil'nymi soedineniiami na osnove dokozageksaenovoi kisloty na gumoral'nyi immunnyi otvet u myshei linii C57BL/6.

The immunotropic activity of three derivatives of docosahexaenic acid (N-docosahexaenoyl-L-serine phosphate, N-docosahexaenoyl-L-threonine phosphate, and N-docosahexaenoyl-L-tyrosine phosphate) in complexes with high-purity human alpha-fetoprotein was evaluated. The polyene compounds stimulate the humoral immunity in mice immunized with T-dependent antigen (ram red blood cells). The immunotropic activity of the alpha-fetoprotein-ligand complexes studied depends on the structure and the content of polyene ligands.

Radiation-induced peroxidation and fragmentation of lipids in a model membrane.

PURPOSE: To ascertain the possibility of fragmentation processes in lipid membranes when acted upon with gamma-radiation under various conditions, and to evaluate fragmentation processes quantitatively in comparison with the lipid peroxidation processes. MATERIALS AND METHODS: Phospholipids as components of multilamellar liposomes exposed to 137Cs gamma-rays at dose-rates of 0.06 and 0.33 Gy s-1 in the dose range 0-18 kGy. Peroxidation products were determined spectrophotometrically and fragmentation products were analysed using thin-layer chromatography and GLC methods. RESULTS: Phosphatidylglycerol containing unsaturated fatty acid residues and free hydroxyl groups underwent both peroxidation and fragmentation when its aqueous dispersions were treated with ionizing radiation. gamma-Radiolysis of multilamellar liposomes led to the formation of peroxidation products, as well as phosphatidic acid and hydroxyacetone, fragmentation products of the initial lipid. Comparable radiation-chemical yields of conjugated-diene products and phosphatidic acid indicate that the probabilities of oxidation and fragmentation processes to occur are approximately equal in this case. In contrast to lipid peroxidation, lipid fragmentation is not accelerated but suppressed by oxygen and appears to be a prevailing process in de-aerated solutions. The phosphatidic acid formed as a result of phosphatidylglycerol fragmentation can intensify the lipid peroxidation. CONCLUSIONS: Treatment of lipid membranes with ionizing radiation leads to the destructive processes within both hydrophobic and hydrophilic moiety of lipids.

[Effect of lysophosphatidylcholine on the radiation-induced lipid peroxidation in liposomes]. / Vliianie lizofosfatidilkholina na radiatsionno-initsiirovannoe perekisnoe okislenie lipidov v liposomakh.

The effect of lysophosphatidylcholine (LPC) on the lipid peroxidation process (LPO) in liposomes of rat liver phosphatidylcholine initiated by irradiation of 137Cs source was studied. The formation of diene conjugates (DC) is shown to increase dramatically on incorporation of more than 10% LPC into liposomes. The dependence of DC proportion on the irradiation dose is practically linear in the range of 0 to 5 kGy. The DC concentration in the liposomes without LPC grows at least to dose of 3.3 kGy and is unchanged on further irradiation. The malonic dialdehide accumulation follows the similar dependence. The LPC effect is neutralized by the incorporation of cholesterol into liposomes. The product of free radical fragmentation of LPC, palmitoxyacetone, practically has no influence on the DC concentration. The reasons of LPC effect on the irradiation initiated LPO in liposomes is discussed.

Liposomes with phosphatidylethanol as a carrier for oral delivery of insulin: studies in the rat.

In this study, phosphatidylethanol formed by phospholipase D catalysed transphosphatidylation of phosphatidylcholine was employed as a component for preparation of liposomal carrier for oral delivery of insulin. Thermotropic behaviour of liposomes from mixtures of dipalmitoyl phosphatidylcholine and dipalmitoyl phosphatidylethanol, and their resistance to pancreatic phospholipase A(2) catalysed hydrolysis were studied. Three kinds of liposomes with insulin were prepared to examine the pharmacological availability of liposomes with phosphatidylethanol: (i) dipalmitoyl phosphatidylcholine/dipalmitoyl phosphatidylethanol (1:1 w/w) liposomes; (ii) dipalmitoyl phosphatidylcholine/dipalmitoyl phosphatidylethanol/palmitoyl-stearoyl sucrose (1:1:0.2) liposomes; and (iii) liposomes composed of natural phosphatidylcholine and phosphatidylinositol (1:1). The resultant liposomes were orally administrated to rats with blood glucose concentration of 270 mg/100 ml in a dose of 12 IU/kg body weight. Blood samples were collected 0.5, 1.5, 3, 5, and 24 h after treatment. Oral administration of all liposomal species resulted in hyperinsulinemia. Hyperinsulinemia induced by liposomes containing dipalmitoyl phosphatidylethanol was attended by a decrease of blood glucose concentration. No correlation between insulin level and glucose concentration in the rat blood after oral administration of phosphatidylinositol-containing liposomes was observed.

Influence of ethanol and phosphatidylethanol on the activity of pancreatic phospholipase A2.

Hydrolysis of dioleoylphosphatidylethanol (DOPEt) and dioleoylphosphatidylcholine (DOPC) catalyzed by phospholipase A2 (PLA2) from porcine pancreas has been studied in single-component and binary liposomes in the absence and in the presence of ethanol. DOPEt (an anionic phospholipid) was found to increase the rate of hydrolysis of zwitterionic DOPC in liposomes under the action of PLA2.

Modification of humoral immune response in C57Bl/6 mice with a complex of alpha-fetoprotein and retinoid acid derivatives.

Amides of all trans-retinoic acid and O-phospho-L-threonine, O-phospho-L-tyrosine, and O-phosphoethanolamine injected intravenously in a dose of 6.8 microg/kg 1.5-3.4-fold increased the count of antibody-producing cells in the spleen of C57Bl/6 mice (primary immune response to sheep erythrocytes). Activity of the complex containing alpha-fetoprotein and L-threonine ligand did not differ from that of free retinoid. This complex holds much promise as a prototype of immunomodulators with a wide range of activity.

[Effect of products of radiation-induced free radical fragmentation of phospholipids and temperature on lipid membranes]. / Vliianie produktov radiatsionno-indutsirovannoi svobodnoradikal'noi fragmentatsii fosfolipidov i temperatury na lipidnye membrany.

Thermotropic behavior of liposomes exposed to gamma-radiation was studied by differential scanning microcalorimetry. It was found that the peak corresponding to the gel-liquid crystal transition for liposomes composed of bovine brain sphingomyelin and dipalmitoyl phosphatidylglycerol broadened and shifted toward the high-temperature region. No effect of irradiation on dipalmitoyl phosphatidylcholine liposomes was observed. Previously it was shown that, on exposure to gamma-rays, sphingomyelin and phosphatidylglycerol, as opposed to phosphatidylcholine, broke down into fragments of lower molecular weight. It is concluded that the accumulation of products of phospholipid fragmentation in the membrane results in the changes of phase transition parameters.

[The characteristics of the radiation-initiated peroxidation of the phosphatidylcholine making up liposomes containing phospholipids which are susceptible to free-radical fragmentation]. / Osobennosti radiatsionno-initsiirovannogo perekisnogo okisleniia fosfatidilkholina v sostave liposom, soderzhashchikh sklonnye k svobodnoradikal'noi fragmentatsii fosfolipidy.

The regularities of accumulation of conjugated dienes and thiobarbituric acid (TBA)-reactive substances under gamma-irradiation of liposomes from rat liver phosphatidylcholine (PC) and its mixtures with the resistant to lipid peroxidation saturated phospholipids and bovine brain sphingomyelin (SM) were studied. It was established that the incorporation of negatively charged dipalmitoylphosphatidylglycerol (DPPG) and dipalmitoylphosphatidylethanol (DPPET) into lipid bilayer resulted in the increase of primary and secondary products of LPO, whereas neutral dipalmitoylphosphatidylcholine (DPPC) and SM involving in the phospholipid mixtures inhibited the peroxidation of PC. For anionic phospholipids, DPPG had more profound activating action on LPO, amongst the neutral phospholipids SM was more potent inhibitor of the reaction. Unlike DPPET and DPPC, DPPG and SM were subjected to free radical fragmentation on gamma-radiation. It is suggested that the intermediates and products of free radical fragmentation may modulate the progress of LPO.

Influence of dinitroglycerol and nitroethyleneglycol lipid derivatives on spectral parameters of human hemoglobin.

The interaction of organic nitrates (nitroethyleneglycol, dinitroglycerol, and their esters with arachidonic acid) with oxyhemoglobin and methemoglobin has been studied. Addition of nitroethyleneglycol and dinitroglycerol to oxyhemoglobin is accompanied by a modest but significant increase in oxidation rate of the heme protein to the high-spin ferri-form--methemoglobin. Arachidonoylglycerol dinitrate exerts a similar but more pronounced effect on hemoglobin: a molar excess of this dinitrate induces the transformation of a significant portion of oxyhemoglobin to methemoglobin, whereas arachidonoylnitroethyleneglycol is inactive. Arachidonoylglycerol dinitrate also induces changes in the spectral characteristics of methemoglobin; this may be due to disintegration of the methemoglobin with the loss of heme. The data demonstrate that some organic nitrates can interact with hemoglobin; this should be taken into account when using the oxyhemoglobin technique for measuring nitric oxide generation from these compounds.

Conversion of hemoglobin to hemichrome by lysophospholipids.

The interaction of lysophospholipids with human oxy- and methemoglobin was studied. Anionic (acidic) lysophospholipids (lysophosphatidylserine, lysophosphatidylinositol, lysophosphatidylethanol, and lysophosphatidic acid) are potent effectors inducing the conversion of both forms of hemoglobin into hemichrome. Zwitterionic lysophospholipids (lysophosphatidylcholine, lysophosphatidylethanolamine, and lysosphingomyelin) did not influence oxyhemoglobin conversion, whereas methemoglobin conversion into hemichrome required much higher concentrations of these lysophospholipids compared to anionic lysophospholipids. Neutralization of negative charge on phosphate group of acidic lysophospholipids by Ca2+ was accompanied by partial or complete loss of their effector properties. The process of hemoglobin conversion to hemichrome is characterized by two isobestic points in the absorption spectra, indicating lack of stable intermediates. The present results are discussed in terms of the biological sense of the asymmetric distribution of phospholipids in the erythrocyte membrane.

The damage to phospholipids caused by free radical attack on glycerol and sphingosine backbone.

The effect of gamma-radiation on aqueous solutions of saturated phospholipids, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dipalmitoyl-sn-glycero-3-phosphoglycerol (DPPG), 1-palmitoyl-2-lyso-sn-glycero-3-phosphocholine (lysoPC), and bovine brain sphingomyelin (SM) has been investigated. It is shown that the phospholipids with an OH group in beta-position to the P-O bond (DPPG and lysoPC), or to the amide bond (SM), undergo a free radical fragmentation. As a result of such fragmentation, stearoylamide, palmitoxyacetone and phosphatidic acid are formed from SM, lysoPC and DPPG, respectively. In parallel with the formation of hydrophobic fragments, an accumulation of hydrophilic species such as oxyacetone and phosphocholine in the irradiated DPPG and lysoPC dispersions was observed. On the basis of the data obtained for free radical transformation of phospholipids and their simplest analogs, such as glycero-1-phosphate, triacetin and 1,2-isopropylidene glycerol, it is suggested that the fragmentation of the radicals derived from the above compounds proceed by a concerted mechanism through a five-membered transition state. The accumulation of hydrophobic fragments in phospholipid membranes is shown to influence the temperature and co-operativity of the 'gel-to-liquid crystal' phase transition. An assumption is made that the fragmentation of phospholipids caused by free radical attack on the hydrophilic moiety, along with lipid peroxidation, may constitute principal mechanisms of radiation-induced damage of biological membranes.

[Formation of hemichrome during reaction of hemoglobin with polar phosphatidylcholine derivatives]. / Obrazovanie gemikhroma pri vzaimodeistvii gemoglobina s poliarnymi proizvodnymi fosfatidilkholina.

Polar phosphatidylcholine derivatives [1-acyl-2-lyso-sn-glycero-3-phosphocholine, 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine (platelet-activating factor), 1-acyl-2-glutaryl-sn-glycero-3-phosphocholine, and 1-acyl-2-azelaoyl-sn-glycero-3-phosphocholine], which are formed in biological structures by enzymatic and free-radical reactions, were studied as effectors of the conversion of methemoglobin and oxyhemoglobin into an oxidized low-spin form referred to as hemichrome. It is shown that all these phosphatidylcholine derivatives act as effectors in the course of the transition of met- and oxyhemoglobin to hemichrome. Among the compounds studied, phosphatidylcholine derivatives containing glutaric and azelaic acids residues have the greatest effect on the rate of hemichrome formation.

[Effects of fatty acid amides on phosphatidylcholine hydrolysis catalyzed by phospholipase A2 in micelles]. / Vliianie amidov zhirnykh kislot na kataliziruemyi fosfolipazoi A2 gidroliz fosfatidilkholina v mitsellakh.

The effect of fatty acid amides on the hydrolysis of natural phosphatidylcholine and its semisynthetic analog, dioleoyl phosphatidylcholine, catalyzed by phospholipase A2 in mixed micelles with Triton X-100 has been studied. Palmitoylamide, oleoylamide, and stearoylamide were shown to be the inhibitors of enzymatic phospholipid hydrolysis.

[Entrapment of antibiotics in liposomes containing phosphatidylethanol]. / Vstraivanie antibiotikov v liposomy, soderzhashchie fosfatidilétanol.

Antibiotic entrapment to liposomes containing phosphatidyl ethanol, a negatively charged phospholipid, as a lipid component was studied. Antibiotics of various groups such as doxorubicin, rifampicin and doxycycline were entrapped to liposomes consisting of a mixture of phosphatidyl choline and phosphatidyl ethanol at a ratio of 1:1 (v/v) or phosphatidyl choline alone. It was shown that the liposomes containing phosphatidyl ethanol were able to entrap the antibiotics in higher amounts by comparison with the liposomes containing phosphatidyl choline. Phosphatidyl ethanol in the composition of the liposomes had the highest effect on the entrapment of doxorubicin.

[The phospholipase A2 hydrolysis of irradiated lipid membranes]. / Gidroliz fosfolipazoi A2 obluchennykh lipidnykh membran.

Phospholipase A2 hydrolysis of dioleoylphosphatidylcholine, dimyristoylphosphatidylcholine or their equimolar mixture with sphingomyelin in liposomes exposed to gamma-radiation has been investigated. Stabilization of the gamma-irradiated lipid bilayer to hydrolysis by sphingomyelin has been shown.