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1.
Biochemistry (Mosc) ; 85(5): 553-566, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32571185

RESUMEN

Inactivated (whole-virion, split, subunit, and adjuvanted) vaccines and live attenuated vaccine were tested in parallel to compare their immunogenicity and protective efficacy. Homologous and heterosubtypic protection against the challenge with influenza H5N1 and H1N1 viruses in a mouse model were studied. Single immunization with live or inactivated whole-virion H5N1 vaccine elicited a high level of serum antibodies and provided complete protection against the challenge with the lethal A/Chicken/Kurgan/3/05 (H5N1) virus, whereas application of a single dose of the split vaccine was much less effective. Adjuvants increased the antibody levels. Addition of the Iso-SANP adjuvant to the split vaccine led to a paradoxical outcome: it increased the antibody levels but reduced the protective effect of the vaccine. All tested adjuvants shifted the ratio between IgG1 and IgG2a antibodies. Immunization with any of the tested heterosubtypic live viruses provided partial protection against the H5N1 challenge and significantly reduced mouse mortality, while inactivated H1N1 vaccine offered no protection at all. More severe course of illness and earlier death were observed in mice after immunization with adjuvanted subunit vaccines followed by the challenge with the heterosubtypic virus compared to challenged unvaccinated animals.


Asunto(s)
Inmunidad , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H5N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/farmacología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Vacunas de Productos Inactivados/inmunología , Adyuvantes Inmunológicos/farmacología , Animales , Humanos , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/virología , Ratones , Ratones Endogámicos BALB C , Vacunación
2.
Bull Exp Biol Med ; 170(2): 181-184, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33263842

RESUMEN

Alimentary atherosclerosis is associated with a significant decrease in the content of phosphatidylcholine, the phospholipid that provides antioxidant protection, in the plasma membrane of liver cells, while the level of phosphatidic acid that initiates generation of superoxides, on the contrary, increases. The level of membrane phosphatidylserine, a target of the scavenger receptors, which initiates removal of damaged cells and modified lipoproteins from the circulation was also elevated. In the blood serum of rabbits receiving an atherogenic diet, the content of cardiolipin involved in the immune mechanisms of atherosclerosis development and a risk factor for thrombosis, sharply increased. The level of lysophosphatidylcholine that mediates initiation and progression of atherosclerosis increased. The content of phosphatidylinositol that is involved in the mechanisms protecting from exposure to excess cholesterol was significantly reduced. Treatment of alimentary atherosclerosis with "empty" phosphatidylcholine nanosomes eliminates the key factors initiating atherosclerosis development.


Asunto(s)
Aterosclerosis/sangre , Membrana Celular/metabolismo , Hígado/metabolismo , Nanopartículas/química , Fosfatidilcolinas/química , Fosfolípidos/química , Animales , Antioxidantes/química , Cardiolipinas/metabolismo , Dieta Aterogénica , Sistema Inmunológico , Lipoproteínas/metabolismo , Lisofosfatidilcolinas/química , Conejos , Factores de Riesgo , Trombosis/inmunología
3.
Pharmacogenomics J ; 16(2): 124-8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25939485

RESUMEN

The PharmacoGenomic Mutation Database (PGMD) is a comprehensive manually curated pharmacogenomics database. Two major sources of PGMD data are peer-reviewed literature and Food and Drug Administration (FDA) and European Medicines Agency (EMA) drug labels. PGMD curators capture information on exact genomic location and sequence changes, on resulting phenotype, drugs administered, patient population, study design, disease context, statistical significance and other properties of reported pharmacogenomic variants. Variants are annotated into functional categories on the basis of their influence on pharmacokinetics, pharmacodynamics, efficacy or clinical outcome. The current release of PGMD includes over 117 000 unique pharmacogenomic observations, covering all 24 disease superclasses and nearly 1400 drugs. Over 2800 genes have associated pharmacogenomic variants, including genes in proximity to intergenic variants. PGMD is optimized for use in annotating next-generation sequencing data by providing genomic coordinates for all covered variants, including Single Nucleotide Polymorphisms (SNPs), insertions, deletions, haplotypes, diplotypes, Variable Number Tandem Repeats (VNTR), copy number variations and structural variations.


Asunto(s)
Bases de Datos Factuales , Farmacogenética , Bases de Datos Genéticas , Mutación , Farmacocinética , Fenómenos Farmacológicos
4.
Opt Express ; 22(21): 25436-43, 2014 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-25401576

RESUMEN

This paper studies the terahertz optical properties of nonlinear potassium titanyl phosphate crystals with different conductivities in the spectral range of 0.2 to 2.6 THz. The observed properties are characterized by several absorption lines lying along different optical axes which represent the relevant potassium sublattice phonon modes. The peculiarities of these absorption lines are attributed to the structural order of potassium ions.


Asunto(s)
Fenómenos Ópticos , Fosfatos/química , Espectroscopía de Terahertz , Titanio/química , Absorción de Radiación , Cristalización , Fonones , Refractometría , Temperatura , Factores de Tiempo
5.
Bull Exp Biol Med ; 157(6): 742-6, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25339590

RESUMEN

Anticonvulsant activity and pharmacokinetics of nanoemulsion and unmodified substance of carbamazepine were compared in experiments on mice. Carbamazepine nanoemulsion demonstrated significant anticonvulsant activity and was superior to unmodified substance of carbamazepine against seizures induced by maximum electric shock and picrotoxin. Relative bioavailability of carbamazepine after administration of nanoemulsion was 160% compared to unmodified substance. Carbamazepine nanoemulsion more effectively penetrated through BBB by 1.5 times in comparison with unmodified substance.


Asunto(s)
Anticonvulsivantes/farmacología , Anticonvulsivantes/farmacocinética , Dietilcarbamazina/farmacología , Dietilcarbamazina/farmacocinética , Emulsiones/farmacología , Emulsiones/farmacocinética , Convulsiones/tratamiento farmacológico , Animales , Disponibilidad Biológica , Barrera Hematoencefálica/metabolismo , Dietilcarbamazina/administración & dosificación , Estimulación Eléctrica , Emulsiones/administración & dosificación , Masculino , Ratones , Nanoestructuras/administración & dosificación , Picrotoxina/toxicidad , Convulsiones/inducido químicamente , Estadísticas no Paramétricas
6.
Bioorg Khim ; 39(3): 326-37, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24397031

RESUMEN

Tumor-associated protein survivin is the bifunctional protein which can participate either in cell division regulation or in apoptosis inhibition depending on its localization and structure state. The aim of this work was to obtain monospecific antibodies useful for investigation of protein structure and functional features. Six affinity purified antibodies directed to different protein regions were obtained. The ability of antibodies obtained to detect survivin in tumor cells and breast cancer tissues was studied. It was shown that antibodies to (1-22) and (95-105) survivin fragments have the highest specific activity. In western-blot antibodies to (1-22) region predominantly binds with survivin-containing complex, which may be the survivin dimer as we suppose, while antibodies to (95-105) region detects only monomeric form of the protein. Breast cancer tissues study demonstrated that survivin monomer presents only in the tumor core tissues, while survivin-containing complex is expressed both in tumor core and tumor periphery tissues. It was shown that antibodies to (1-22) fragment detect predominantly nuclear survivin, which participates in mitosis regulation, while antibodies to (95-105) fragment gave nucleoplasm and cytoplasm staining at all stages of cell cycle. Thereby antibodies obtained are the useful tool for structure-functional study of survivin.


Asunto(s)
Anticuerpos/inmunología , Neoplasias de la Mama/inmunología , Proteínas Inhibidoras de la Apoptosis/inmunología , Péptidos/inmunología , Anticuerpos/química , Afinidad de Anticuerpos/inmunología , Neoplasias de la Mama/patología , Femenino , Células HeLa , Humanos , Proteínas Inhibidoras de la Apoptosis/química , Péptidos/química , Péptidos/aislamiento & purificación , Survivin
7.
Bull Exp Biol Med ; 151(4): 536-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22448385

RESUMEN

We propose a method of precise measurement of the content of nanoparticles carrying a fluorescent label in platelets. Examination under a broadband filter does not allow distinguishing platelets containing and not containing nanoparticles despite different staining of platelets and nanoparticles. Print Screen image of the sample made at the moment of sample motion divides the colors of nanoparticles and platelets and yields two clear-cut spots of different colors on the monitor indicating the presence of nanoparticles in platelets.


Asunto(s)
Plaquetas/metabolismo , Endocitosis , Microscopía Fluorescente/métodos , Nanopartículas , Plaquetas/ultraestructura , Humanos , Microscopía Electrónica
8.
Eksp Klin Farmakol ; 74(5): 31-4, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-21809695

RESUMEN

The effect of lipid nanocomplexes loaded with acetylsalicylic acid (aspirin) on platelet aggregation in vitro was investigated. The antithrombotic effect of aspirin in complex with liposomes prepared from pig brain glycosphingolipids is not only significantly higher compared to control, but also accompanied by leveling of the development of proaggregant effects. It was shown that ADP-induced platelet aggregation is reduced by the introduction of electrostatic charge in the structure of lipid bilayer of liposomes. The effect achieved for the liposomes possessing a negative charge was more pronounced in comparison to the effect of positively charged liposomes.


Asunto(s)
Aspirina/farmacología , Plaquetas/efectos de los fármacos , Trastornos Cerebrovasculares/sangre , Glicoesfingolípidos/farmacología , Liposomas/sangre , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Adenosina Difosfato/farmacología , Animales , Plaquetas/citología , Química Encefálica , Trastornos Cerebrovasculares/tratamiento farmacológico , Trastornos Cerebrovasculares/patología , Cromatografía en Capa Delgada , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Glicoesfingolípidos/química , Humanos , Membrana Dobles de Lípidos/sangre , Membrana Dobles de Lípidos/química , Liposomas/química , Nanoestructuras/química , Electricidad Estática , Porcinos
9.
Prikl Biokhim Mikrobiol ; 45(2): 181-7, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-19382705

RESUMEN

The effect of hexylresorcinol (HR), a chemical analogue of microbial anabiosis autoinducers of the alkylhydroxybenzene (AHB) group, on the stability of biological membranes and monolamellar liposomes formed of egg phosphatidylcholine (ePC) was studied. According to spectrophotometry and electron microscopy studying of HR-loaded liposomes in the presence of a surface-active agent Tween 20, the critical ratio between HR and ePC for liposome preservation was found to be close to equimolar. The trends in HR influence on membrane structural organization and stability confirmed in experiments on liposomes were also reproduced on intact bacterial cells explaining non-species-specific effect of AHBs. The demonstrated high efficiency of AHB biocides may be used in material and equipment protection against biocorrosion.


Asunto(s)
Antiinfecciosos/química , Bacterias/crecimiento & desarrollo , Hexilresorcinol/química , Liposomas Unilamelares/química , Levaduras/crecimiento & desarrollo , Antiinfecciosos/farmacología , Hexilresorcinol/farmacología , Fosfatidilcolinas/química , Fosfatidilcolinas/farmacología , Polisorbatos/química , Polisorbatos/farmacología , Tensoactivos/química , Tensoactivos/farmacología , Liposomas Unilamelares/farmacología
10.
Biomed Khim ; 64(3): 268-275, 2018 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-29964264

RESUMEN

Synthesis of lipoilcarnosine (LipC) - a conjugated molecule based on two natural antioxidants, carnosine and a-lipoic acid, is described. Its physico-chemical, antioxidant properties and biological activity are characterized. According to reversed-phase HPLC with a UV detector, purity of the final product was 89.3%. The individuality of the obtained sodium salt of LipC was confirmed by tandem HPLC-mass spectrometry. High resistance of LipC to hydrolysis with serum carnosinase was demonstrated. The antioxidant activity of LipC measured by reaction with the formation of thiobarbituric acid reacting substances and kinetic parameters of iron-induced chemiluminescence was higher than that of carnosine and lipoic acid. LipC did not affect viability of SH-SY5Y human neuroblastoma culture cells, differentiated towards the dopaminergic type, at concentrations not exceeding 5 mM. At the concentration range of 0.1-0.25 mM LipC protected neuronal cells against 1-methyl-4-phenylpyridinium (MPP + )-induced toxicity.


Asunto(s)
Antioxidantes , Carnosina , Intoxicación por MPTP/tratamiento farmacológico , Antioxidantes/síntesis química , Antioxidantes/química , Antioxidantes/farmacología , Carnosina/análogos & derivados , Carnosina/síntesis química , Carnosina/química , Carnosina/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Intoxicación por MPTP/metabolismo , Intoxicación por MPTP/patología
11.
Bioorg Khim ; 33(5): 485-510, 2007.
Artículo en Ruso | MEDLINE | ID: mdl-18050655

RESUMEN

A great number of natural substances affect the complement system in addition to its natural regulators. Among the complement effectors, the most important are inhibitors of the activation cascade. The necessity of searching for preparations capable of a purposeful effect on complement by inhibition of single stages of the activation cascade and without influence on its other functions is connected with the current importance of use in medicine of novel therapeutic regulators of the complement system. Important directions are the search for complement inhibitors that (a) interfere with the rejection of transplants; (b) can replace C1 inhibitor in hereditary angioedema, and (c) have a high anti-inflammatory activity in the therapy of rheumatic diseases, diabetes, and other autoimmune disorders. It is expedient to use the available techniques for the directed detection of the action of medicinal substances on complement, which allow the determination of their action on the complement system at various stages of the cascade of its activation.


Asunto(s)
Inactivadores del Complemento/clasificación , Inactivadores del Complemento/farmacología , Proteínas del Sistema Complemento/efectos de los fármacos , Animales , Inactivadores del Complemento/química , Evaluación Preclínica de Medicamentos/métodos , Humanos
12.
Biochim Biophys Acta ; 1259(1): 23-8, 1995 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-7492611

RESUMEN

Bile-model systems containing cholesterol (CH), phosphatidylcholine (PC) and sodium cholate (NaC) at concentrations similar to those found in supersaturated human gall bladder bile ([CH]/[PC] = 0.60 +/- 0.01; CH saturation index, CSI = 1.58 +/- 0.03) were prepared by mixing PC-CH vesicles with NaC micellar solutions. Following mixing, the dispersion became transparent and gave rise to high resolution 1H-NMR spectra typical of mixed micellar systems. Cryo-transmission electron micrographs of specimens vitrified at that stage support the conclusion that the vesicles had become completely micellized. Following micellization, the metastable (cholesterol-supersaturated) bile-models spontaneously underwent a series of reorganizational steps: first, cholesterol-rich vesicles with a [CH]/[PC] ratio of 1.57 +/- 0.69 were formed, in co-existence with a mixed micellar system with [CH]/[PC] = 0.43 +/- 0.01 and CSI = 1.12 +/- 0.03. The resultant cholesterol-rich vesicles subsequently aggregated and cholesterol crystals of varying sizes and shapes appeared within the aggregates: needle-like structures were first observed, followed by clusters of those crystals and of helical crystals. Eventually, typical plate-like cholesterol crystals appeared, at which time some of the PC returned to the non-particulate (isotropic) phase. Consequently, the system contained cholesterol crystals coexisting with mixed micelles, whose composition was close to the limit of saturation (CSI = 1.08). These findings confirm the sequence of events preceding the appearance of cholesterol crystals, as previously proposed in our less detailed studies ((1990) Hepatology 12, 149S) and support the relevance of the morphologically similar results of Konikoff et al. ((1992) J. Clin. Invest. 90, 1155) obtained in a very dilute supersaturated bile-model.


Asunto(s)
Bilis/química , Colesterol/química , Colesterol/aislamiento & purificación , Precipitación Química , Ácido Cólico , Ácidos Cólicos/química , Ácidos Cólicos/aislamiento & purificación , Vesícula Biliar/fisiología , Humanos , Cinética , Modelos Biológicos , Nefelometría y Turbidimetría , Fosfatidilcolinas/química , Fosfatidilcolinas/aislamiento & purificación
13.
Biochim Biophys Acta ; 1235(2): 256-62, 1995 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-7756333

RESUMEN

The methods for partition coefficient (Kp) determination were developed for different concentrations of N-(2-hydroxybenzyl)-omega-amino carbonic acids, a new class of amphipathic fatty acid derivatives (An), their deutero (AnD) and bromine (AnBr) derivatives. To do this the following methods were used: 2H-NMR, equilibrium dialysis, centrifugation and fluorescence spectroscopy. Kp dependence on the An concentration is discussed. Kp values for AnBr were more than 120-times higher than those for An, the differences between them being smaller than those for the corresponding An. This series of new amphipathic compounds can be used as probes for membrane studies.


Asunto(s)
Ácido Carbónico/química , Membrana Celular/química , Bromo , Ácido Carbónico/análisis , Centrifugación , Fenómenos Químicos , Química Física , Deuterio , Diálisis , Espectroscopía de Resonancia Magnética , Matemática , Espectrometría de Fluorescencia
14.
Bioorg Khim ; 31(3): 320-5, 2005.
Artículo en Ruso | MEDLINE | ID: mdl-16004391

RESUMEN

New cyclopropane derivatives of betulin were synthesized by attachment of dichlorocarbenes or dibromocarbenes to the double bond of betulin diacetate, followed by the deprotection of hydroxyl groups. The betulin cyclopropane derivative was obtained from 20,29-dihydro-20,29-dichloromethylenebetulin by treatment with lithium in tert-butanol. These compounds were converted into the corresponding derivatives of betulonic acid by oxidation with chromium trioxide. The reduction of oxo group with sodium borohydride led to the corresponding derivatives of betulinic acid. 20,29-Dihydro-20,29-dichloromethylenebetulinic acid proved to be the most cytotoxic toward human melanoma of the Colo 38 and Bro lines and human ovarian carcinoma of the CaOv line (IC50 10 microM). 20,29-Dihydro-20,29-dibromomethylenebetulinic acid inhibited the growth of the Bro melanoma cell line and the CaOv carcinoma cell line practically by 50% at a concentration of 10 microM. The other derivatives of betulinic and betulonic acids were active toward all of the three cancer cell lines at concentrations higher than 10 microM. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2005, vol. 31, no. 3; see also http://www.maik.ru.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Ciclopropanos/síntesis química , Ciclopropanos/farmacología , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/síntesis química , Ácido Oleanólico/farmacología , Triterpenos/síntesis química , Triterpenos/farmacología , Antineoplásicos/química , Carcinoma/tratamiento farmacológico , Línea Celular Tumoral , Ciclopropanos/química , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Melanoma/tratamiento farmacológico , Ácido Oleanólico/química , Neoplasias Ováricas/tratamiento farmacológico , Triterpenos Pentacíclicos , Triterpenos/química , Ácido Betulínico
15.
FEBS Lett ; 340(1-2): 78-82, 1994 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-8119412

RESUMEN

The evolution of microstructures present in human gallbladder and hepatic bile was observed simultaneously by video-enhanced light microscopy (VELM) and transmission electron microscopy of vitrified specimens (cryo-TEM), as a function of time after withdrawal from patients. Fresh centrifuged gallbladder bile samples contained small (6 nm) spherical micelles in coexistence with vesicles (40 nm). Out of the seven bile samples investigated four contained, in addition, two types of elongated aggregates that have not been previously described. Uncentrifuged gallbladder bile also contained a mixture of ribbon- and plate-like crystals seen by VELM, but not by cryo-TEM. In aged (3-6-week-old) gallbladder bile samples VELM also revealed spiral and helical crystal structures. No such crystals were present in hepatic bile samples, although microcrystals, not observable by VELM were seen by cryo-TEM in addition to micelles and vesicles. The similarity of these observations to those observed in bile models lends strong support for the validity of the model systems. Furthermore, the presence of microcrystals in hepatic bile samples, apparently devoid of crystals by light microscopy, indicates that under certain conditions the common criterion of 'nucleation time' (NT), based on light microscopy, does not represent the real time of nucleation. In the human bile samples investigated in this study the dissociation between NT and the time of observation of microcrystals was seen in hepatic but not in gallbladder bile samples. Hence, crystal growth may be rate limiting only in dilute biles.


Asunto(s)
Bilis/química , Lípidos/análisis , Microscopía/métodos , Bilis/metabolismo , Colelitiasis/metabolismo , Vesícula Biliar/metabolismo , Humanos , Hígado/metabolismo , Microscopía Electrónica/métodos
16.
Microsc Res Tech ; 39(1): 85-96, 1997 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-9329021

RESUMEN

Investigation of cholesterol crystallization is essential for the understanding of gallstone formation. Previous work has revealed a variety of aggregates of different sizes and shapes prior to the appearance of "classical" plate-like cholesterol monohydrate crystals both in native biles and model systems. In this article, we review existing data based on various microscopic techniques and present data on microstructural pathways leading to cholesterol crystal formation in two different bile models and in native bile. In continuation of our recent investigation of microstructures in nucleating human bile, we now present data suggesting that polymorphism is not limited to complex native bile, but also appears in two, simplified model systems. These studies employed cryo-transmission electron microscopy (cryo-TEM) and video-enhanced light microscopy, using Nomarski optics (VELM). Only the combined use of these two complementary, non-perturbing direct methods can cover the whole range of microstructures ranging from a few nanometers to several microns. Concentrated isotropic solutions of bile models, composed of cholesterol, lecithin and taurocholate, were diluted to induce cholesterol supersaturation and start an evolution of microstructures, leading to cholesterol crystallization. Initially, small spheroidal micelles were observed by cryo-TEM. Subsequently, uni-, oligo- and multilamellar vesicles, compatible with structures seen at the same time by VELM, appeared in coexistence with micelles. Thereafter, during a dynamic phase of cholesterol crystallization, filaments, tubular and helical microstructures, as well as classical plate-like cholesterol monohydrate crystals were noted by light microscopy. Eventually, large plate-like crystals were observed by VELM, while cryo-TEM revealed only small spheroidal micelles. The crystallization process in native human bile during ex vivo incubation was found to bear close resemblance to the findings in the model systems, further supporting the applicability of these systems to the exploration of microstructural aspects of nucleating human bile.


Asunto(s)
Bilis/química , Estructura Molecular , Colelitiasis/metabolismo , Colesterol/química , Cristalización , Humanos , Micelas , Microscopía Electrónica/métodos , Microscopía por Video
17.
Chem Phys Lipids ; 85(1): 75-89, 1997 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-9032946

RESUMEN

The chemical structure of a phosphoglucolipid from the membrane of the bacterium Acholeplasma laidlawii strain B-PG9 has been determined by high resolution NMR to be 1,2-diacyl-3-O-[glycerophosphoryl-6-O-(alpha-D-glucopyranosyl-(1 -->2)-O-alpha-D-glucopyranosyl)]-sn-glycerol (GPDGlcDAG). It was concluded that this lipid has exactly the same structure as one of the phosphoglucolipids from A. laidlawii strain A-EF22. By cryo transmission electron microscopy (cryo-TEM) and NMR diffusion techniques it was shown that, in highly diluted aqueous solutions, this membrane lipid forms long thread-like micelles in equilibrium with lipid vesicles. The cause of the occurrence of these different aggregates is discussed in terms of the varying molecular shapes of the lipid because of a heterogeneous composition of the acyl chains. A second membrane phosphoglucolipid from the bacterium, namely 1,2-diacyl-3-O-[glycerophosphoryl-6-O-(alpha-D- glucopyranosyl-(1 -->2)-monoacylglycerophosphoryl-6-O-alpha-D-glucopyranosyl)]-sn-gl ycerol (MABGPDGlcDAG), was found to form only a lamellar liquid crystalline phase coexisting with water.


Asunto(s)
Acholeplasma laidlawii/química , Glucolípidos/química , Lípidos de la Membrana/química , Espectroscopía de Resonancia Magnética , Microscopía , Microscopía Electrónica , Microscopía por Video , Conformación Molecular
18.
J Liposome Res ; 11(1): 55-71, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-19530919

RESUMEN

The active loading of liposomes with dopamine in response to an ammonium sulfate gradient was studied. This method can be regarded as a mean to more efficiently improve the liposomal dopamine/lipids ratio in comparison to conventional methods of liposome preparation. Trapping efficiency of dopamine into liposomes exhibiting a transmembrane ammonium sulfate gradient was shown to be dependent on liposome lipid composition, lipid concentration and temperature. Dopamine-containing liposomes with alpha-tocopherol in the lipid bilayer were shown to be stable at least for three weeks. It has been found that intraperitoneal (i.p.) administration of conventionally prepared dopamine-containing liposomes as well as liposomes with increased dopamine/lipid ratio may efficiently suppress the expression of parkinsonian symptoms in C57BL/6 mice with experimental parkinsonian syndrome. On the other hand, only through increasing of liposomal dopamine/lipid ratio the complete compensation of dopamine deficiency in the mice brain was achieved. The obtained data may be considered as biochemical evidence in favor of liposomes' ability to act as a carrier system for the delivery of dopamine into the brain.

19.
Lab Anim ; 10(2): 105-9, 1976 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-933459

RESUMEN

Keratitis was noted in mice which were splenectomized and subsequently treated with immunosuppressive drugs. It was found that anaesthesia was the cause of the lesion and not the azathioprine or meticorten administration.


Asunto(s)
Azatioprina/efectos adversos , Queratitis/veterinaria , Ratones , Prednisona/efectos adversos , Enfermedades de los Roedores/inducido químicamente , Animales , Femenino , Queratitis/inducido químicamente , Pentobarbital/efectos adversos
20.
Bioorg Khim ; 9(8): 1101-5, 1983 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-6680305

RESUMEN

Psychosine prepared from bovine brain cerebroside was used for synthesis of galactosphingolipids with DL-, D-, or L-2-hydroxyhexadecanoic acids and 6-(2'-anthroyl) hexanoic acid. Psychosine was N-acetyl with p-nitrophenyl 2-acetoxyhexadecanoates in the presence of hydroxybenzotriazole to give cerebrosides. The 6-(2'-anthroyl)hexanoic acid reaction with psychosine was effected via its acyl chloride.


Asunto(s)
Cerebrósidos/síntesis química , Animales , Química Encefálica , Bovinos , Cerebrósidos/aislamiento & purificación , Métodos
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