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1.
Artigo em Russo | MEDLINE | ID: mdl-35758078

RESUMO

BACKGROUND: Olfactory nerve schwannomas are extremely rare. Their origin is still unclear, since olfactory nerve has no Schwann cells. There are about 70 case reports of olfactory nerve schwannoma in the world literature. Original articles devoted to this issue are currently absent. RESULTS: We present a 55-year-old patient with olfactory nerve schwannoma who underwent surgery at the Federal Center of Neurosurgery in Novosibirsk. MRI revealed extracerebral mass lesion of anterior cranial fossa base with left-sided lateralization resembling meningioma of the olfactory fossa. The patient underwent microsurgical resection of mass lesion of anterior cranial fossa base through left-sided lateral supraorbital craniotomy. The tumor macroscopically resembled schwannoma. Total resection was carried out. Considering morphological structure and immunomorphological characteristics, we verified schwannoma Grade 1. CONCLUSION: Olfactory nerve schwannomas are rare tumors with benign histological structure. Relapses after total resection are unlikely. However, further research of this rare pathology and long-term postoperative follow-up are required.


Assuntos
Neoplasias Meníngeas , Meningioma , Neurilemoma , Craniotomia , Humanos , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Pessoa de Meia-Idade , Neurilemoma/diagnóstico por imagem , Neurilemoma/cirurgia , Procedimentos Neurocirúrgicos
2.
Carbohydr Polym ; 254: 117251, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357847

RESUMO

The research described here presents data on the effect of galactans of red algae, carrageenans (λ/µ/ν-, κ-, κ/ß-, and ι/κ-types), and agar on complement system activation in normal human serum. The experiments were based on well surfaces coated with triggering agents for binding initiating complement components -C3 and C4. The sulfated galactans inhibited C3 binding to lipopolysaccharide with direct dependence on the sulfation degree of polysaccharides. Sulfation degree was also important in carrageenans' capacity to reduce C4 binding to mannan. However, C4 binding to antibodies was considerably activated by carrageenans, especially with 3,6-anhydrogalactose. The gelling carrageenans were able to block antigen binding centers of total serum IgM and with more intensity than non-gelling. No structural characteristics mattered in ameliorating C5 cleavage by plasmin in extrinsic protease complement activation, but λ/µ/ν- and κ/ß-carrageenans almost completely inhibited C5 cleavage. Thus, galactans participated in cell surface biology by imitating surface glycans in inhibition of C3 binding and mannose binding lectin, but as to the tthe heclassical pathway these substances stimulated complement, probably due to their structure based on carrabiose.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Galactanos/química , Galactanos/farmacologia , Alga Marinha/química , Anticorpos/sangue , Configuração de Carboidratos , Sequência de Carboidratos , Carragenina/química , Carragenina/farmacologia , Via Alternativa do Complemento/efeitos dos fármacos , Via Clássica do Complemento/efeitos dos fármacos , Galactanos/sangue , Humanos , Técnicas In Vitro , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Polissacarídeos/química , Polissacarídeos/farmacologia , Rodófitas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos/química
3.
Int J Biol Macromol ; 164: 3025-3037, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32827616

RESUMO

Genomic analysis of the marine bacterium Wenyingzhuangia fucanilytica CZ1127T revealed the presence of four fucoidanase genes fwf1, fwf2, fwf3, fwf4 that belonged to the glycoside hydrolase family 107 (GH107, CAZy), which is located in one gene cluster putatively involved in fucoidan catabolism. Genes encoding two fucoidanases fwf1 and fwf2 were cloned, and the proteins FWf1 and FWf2 were produced in Escherichia coli cells. The recombinant fucoidanases were purified and the biochemical properties of these enzymes were studied. The amino acid sequences of FWf1 and FWf2 showed 41 and 51% identity respectively with a fucoidanase FcnA from the marine bacterium Mariniflexile fucanivorans, with the established 3D structure. Structures of the oligosaccharides produced during enzymatic hydrolysis of fucoidan by FWf1 and FWf2 have been determined by NMR spectroscopy. Detailed substrate specificities of FWf1 and FWf2 were studied using fucoidans and sulfated fucooligosaccharides with different structures. Both fucoidanases catalyzed hydrolysis of 1→4-glycosidic bonds between sulfated α-l-fucose residues but had different specificities regarding sulfation patterns of the fucose residues in fucoidan molecules. Specific cleavage sites recognizable by the fucoidanases in fucoidan molecules were determined. The obtained results provide new knowledge about differences between specificities of the fucoidanases belonging to the GH107 family.


Assuntos
Flavobacteriaceae/enzimologia , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Polissacarídeos/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Flavobacteriaceae/genética , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Hidrólise , Espectroscopia de Ressonância Magnética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
4.
Artigo em Russo | MEDLINE | ID: mdl-28291217

RESUMO

Resection of anterior clinoidal meningiomas is a challenging task due to their localization, frequent involvement of the major cerebral arteries and cranial nerves, a high risk of postoperative neurological deficits, and low radicalness of surgery. AIM: To evaluate the radicalness of microsurgical removal and a neurological deficit in the early postoperative period in patients with anterior clinoidal meningiomas. MATERIAL AND METHODS: A total of 35 patients with anterior clinoidal meningiomas underwent surgery at the Department of Neurooncology of the Novosibirsk Federal Neurosurgical Center in the period from 2013 to July 2016. There were 29 (82.9%) females and 6 (17.1%) males. The mean patient age was 50.1 years (31-72 years). According to the Al-Mefty classification (1990), type 1 tumors occurred in 10 (28.6%) patients, type 2 tumors were in 22 (62.8%) patients, and type 3 tumors were in 3 (8.6%) patients. Twenty four (68.6%) patients had large (greater than 4.0 cm) tumors, 7 (20.0%) patients had medium (2.0-4.0 cm) tumors, and 4 (11.4%) patients had small (less than 2.0 cm) meningiomas. The tumor involved the major arteries in 21 (60.0%) patients. RESULTS: The lateral supraorbital approach was used in 26 (74.3%) patients, and the pterional approach was used in 9 (25.7%) cases. The tumor was resected totally (Simpson II) in 25 (71.4%) cases and subtotally (Simpson IV, subtype A and B) in 10 (28.6%) patients. In the early postoperative period, cerebral symptoms regressed in 20 (57.1%) patients; visual acuity improved in 2 of 13 (15.4%) patients. Four (11.4%) patients developed IIIrd nerve palsy; 2 (5.7%) patients developed severe hemiparesis. The mortality rate was 2.9%. CONCLUSION: The completeness of resection directly depends on the tumor consistency: soft meningiomas can be totally resected (Simpson II) with a good functional outcome. In the case of solid tumors, total resection may lead to serious ischemic disorders with a high risk of death.


Assuntos
Neoplasias Meníngeas , Meningioma , Adulto , Idoso , Feminino , Humanos , Masculino , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/fisiopatologia , Neoplasias Meníngeas/cirurgia , Meningioma/patologia , Meningioma/fisiopatologia , Meningioma/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Phytother Res ; 24(11): 1730-2, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20737623

RESUMO

Ten secondary metabolites including flavonoids (1-8), caffeic (9) and chlorogenic (10) acids were structurally identified from the extract of Sakhalin bilberry Vaccinium smallii leaves and studied in vitro as potential cancer-preventive agents. The results showed that compounds 1-10 inhibited EGF-induced neoplastic transformation of mouse JB6 Cl 41 P+ cells in soft agar with an inhibition concentration (INCC50) of 20-80 µm. Moreover, all these natural products were non-toxic against JB6 Cl 41 P+ cells up to a concentration of 200 µm.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Vaccinium myrtillus/química , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Ácidos Cafeicos/isolamento & purificação , Ácidos Cafeicos/farmacologia , Linhagem Celular Tumoral , Ácido Clorogênico/isolamento & purificação , Ácido Clorogênico/farmacologia , Flavonoides/isolamento & purificação , Células HeLa , Humanos , Camundongos , Estrutura Molecular , Folhas de Planta/química
6.
J Nat Prod ; 64(7): 945-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11473430

RESUMO

Two novel steroidal 24-O-xylosides, designated as rathbuniosides R(1) (1) and R(2) (2), and the known amurensoside A (3) and 3-O-sulfomarthasterone (4) have been isolated from the starfish Asterias rathbuni. The structures of all the compounds were determined from their spectroscopic data, including one- and two-dimensional NMR methods. The compounds 1 and 4 inhibit the cell division of fertilized sea urchin eggs at doses of 7.0 x 10(-5) and 2.9 x 10(-5) M, respectively.


Assuntos
Divisão Celular/efeitos dos fármacos , Glicosídeos/isolamento & purificação , Toxinas Marinhas/farmacologia , Estrelas-do-Mar/química , Esteroides/isolamento & purificação , Animais , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Glicosídeos/química , Glicosídeos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Óvulo/citologia , Óvulo/efeitos dos fármacos , Óvulo/metabolismo , Ouriços-do-Mar , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Esteroides/química , Esteroides/farmacologia , Relação Estrutura-Atividade
8.
Artigo em Inglês | MEDLINE | ID: mdl-11163304

RESUMO

Free sterol fractions from the holothurians (sea cucumbers) Synapta maculata, Cladolabes bifurcatus and Cucumaria sp. have been isolated and studied by HPLC, GLC, GLC-MS and NMR methods. Forty seven sterols were identified, including several rare ones. In contrast with previously studied holothurians, the presence of a minor amount of Delta7 sterols was indicated in the sterols of S. maculata. This animal contains predominantly Delta(9(11))sterols as well as an abnormally high concentration of Delta5 sterols. In C. bifurcatus and Cucumaria sp., 14alpha-methyl and 4alpha,14alpha-dimethyl-Delta(9(11))sterols were found to be the main sterol constituents. Peculiarities of sterol distribution and the relationship between sterol compositions and taxonomic positions, ecology and toxicity of the corresponding sea cucumbers were discussed.


Assuntos
Esteróis/isolamento & purificação , Esteróis/metabolismo , Animais , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Modelos Químicos , Pepinos-do-Mar , Especificidade da Espécie , Esteróis/química
9.
J Nat Prod ; 63(10): 1349-55, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11076550

RESUMO

Three new triterpene glycosides, calcigerosides D(1) (1), D(2) (2), and E (3), have been isolated from the sea cucumber Pentamera calcigera. Their structures have been deduced from extensive spectral analysis (NMR and MS) and chemical evidence. All the compounds are disulfated pentaosides differing in aglycon structure and position of sulfate group, which were determined by the measurement of NT(1) values in the cases of glycosides 1 and 2. Glycoside 1 is a nonholostane derivative, that is, it lacks an 18(20)-lactone, which is very rare among the sea cucumber glycosides.


Assuntos
Glicosídeos/isolamento & purificação , Pepinos-do-Mar/química , Triterpenos/isolamento & purificação , Animais , Glicosídeos/química , Espectroscopia de Ressonância Magnética , Triterpenos/química
10.
J Nat Prod ; 63(8): 1178-81, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10978224

RESUMO

A reinvestigation of the polar steroid fraction from the starfish Aphelasterias japonica, collected near the Russian shore of the Sea of Japan, has afforded two new compounds, the disulfated quinovoside aphelasteroside C (1) and the monosulfated polyhydroxysteroid aphelaketotriol (2). Compounds 1 and 2 contain a unique 23-oxo-24-hydroxylated side chain that is unprecedented in marine steroids. The known compounds cheliferoside L1 (3), 3-O-sulfoasterone (4), forbeside E3 (5), and 3-O-sulfothornasterol A (6) were also isolated from this source. Compounds 1-3, 5, and 6 showed hemolytic activity to mouse erythrocytes.


Assuntos
Estrelas-do-Mar/química , Esteroides/isolamento & purificação , Animais , Bioensaio , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cromatografia em Camada Fina , Eritrócitos/química , Espectroscopia de Ressonância Magnética , Camundongos , Rotação Ocular , Federação Russa , Sódio/análise , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Atômica , Espectrofotometria Infravermelho , Esteroides/química , Esteroides/farmacologia
11.
J Nat Prod ; 63(1): 65-71, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10650081

RESUMO

Three new monosulfated triterpene glycosides, calcigerosides B (2), C(1) (3), and C(2) (4), along with the known cucumarioside G(2) (1), have been isolated from the sea cucumber Pentamera calcigera. Their structures have been deduced from extensive spectral analysis (NMR and MS) and chemical evidence. Compounds 2-4 present a novel pentasacharide chain never reported before in sea cucumber triterpene glycosides. The desulfated derivatives of calcigerosides B, C(1), and C(2) (5, 7, and 9, respectively) showed moderate cytotoxicity (IC(50) = 5 microg/mL) against a selection of four human and mouse tumor cell lines.


Assuntos
Glicosídeos/isolamento & purificação , Pepinos-do-Mar/química , Triterpenos/isolamento & purificação , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Camundongos , Estrutura Molecular , Triterpenos/química , Triterpenos/farmacologia , Células Tumorais Cultivadas
12.
J Nat Prod ; 62(2): 279-82, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10075759

RESUMO

Four new 24-O-biosides of 5alpha-cholestane-3beta,6alpha,8,15beta, 24-pentaol, designated as mediasterosides M1 (1), M2 (2), M3 (3), and M4 (4), and the previously known 5alpha-cholestane-3beta,6beta,8, 15alpha,16beta,26-hexaol (5) have been isolated from the deep-water starfish Mediaster murrayi. Glycosides 1-3 contain rare carbohydrate moieties with (1-->5) bonds between the monosaccharide units. Compounds 1 and 2 showed the inhibition of cell division of fertilized sea urchin eggs and exhibited moderate hemolytic activities.


Assuntos
Glicosídeos/isolamento & purificação , Estrelas-do-Mar/química , Esteroides/química , Animais , Sequência de Carboidratos , Glicosídeos/química , Glicosídeos/farmacologia , Hemólise/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
13.
J Nat Prod ; 60(8): 808-10, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9287416

RESUMO

The new triterpene glycoside koreoside A (1) has been isolated from the sea cucumber Cucumaria koraiensis. Koreoside A (1) is the first glycoside reported from holothurians that presents a delta(7) nonholostane aglycon without a lactone group and with a shortened side chain. Its structure has been elucidated by 13C and 1H NMR as well as FABMS studies.


Assuntos
Glicosídeos/isolamento & purificação , Pepinos-do-Mar/química , Triterpenos/isolamento & purificação , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Glicosídeos/química , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Triterpenos/química
14.
J Nat Prod ; 60(8): 817-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9287417

RESUMO

The new triterpene saponin eximisoside A (1) has been isolated from the Far-Eastern sea cucumber Psolus eximius and its structure elucidated by 1D and 2D NMR (13C, 1H, 1H-1H COSY, HMQC, and NOESY spectra), and FABMS studies. The structural features of eximisoside A (1) are the rare presence of a 23 double bond in the aglycon and the absence of quinovose, typically found in the oligosaccharide chain of holothurian glycosides.


Assuntos
Glicosídeos/química , Pepinos-do-Mar/química , Triterpenos/química , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Espectrometria de Massas de Bombardeamento Rápido de Átomos
15.
Scanning Microsc Suppl ; 10: 349-56; discussion 356-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9601552

RESUMO

X-ray microscopes provide higher resolution than visible light microscopes. Wet, biological materials with a water thickness of up to about 10 microns can be imaged with good contrast using soft X-rays with wavelengths between the oxygen and carbon absorption edges (at 24 and 43 A). The Stony Brook group has developed and operates a scanning transmission X-ray microscope (STXM) at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The microscope is used for imaging with a current resolution of 50 nm, and for elemental and chemical state mapping. Radiation damage imposes a significant limitation upon high resolution X-ray microscopy of room temperature wet specimens. Experience from electron microscopy suggests that cryo techniques allow vitrified specimens to be imaged repeatedly. This is due to the increased radiation stability of biological specimens in the frozen hydrated state. Better radiation stability has been shown recently with a cryo transmission X-ray microscope developed by the University of Göttingen, operating at the BESSY storage ring in Berlin, Germany. At Stony Brook, we are developing a cryo scanning transmission X-ray microscope (CryoSTXM) to carry out imaging and spectro-microscopy experiments on frozen hydrated specimens. This article will give an outlook onto the research projects that we plan to perform using the CryoSTXM.


Assuntos
Técnicas de Preparação Histocitológica , Microscopia/métodos , Animais , Cromossomos/química , Cromossomos/ultraestrutura , Eritrócitos/citologia , Eritrócitos/parasitologia , Congelamento , Humanos , Masculino , Microscopia/instrumentação , Plasmodium falciparum/citologia , Plasmodium falciparum/crescimento & desenvolvimento , Espermatozoides/citologia , Água , Raios X
16.
Cell Immunol ; 158(1): 29-45, 1994 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-7522129

RESUMO

Decidual and peripheral blood lymphocyte subsets were studied for their expression of CD44, L-selectin (Leu-8), CD54, and CD11b cell adhesion molecules (CAM). Most CD3+, CD4+, CD8+, and CD56+ cells in decidua were L-selectin- and CD44+, i.e., had a phenotype consistent with mucosa-homing preference of decidual lymphocytes (DL). We observed trimodal staining of decidual and peripheral blood CD56+ and CD8+ cells with anti-CD44 monoclonal antibody; negative, weakly positive, and brightly positive subpopulations were evident. Relatively high levels of CD44-negative CD56+ and CD8+ cells were found in decidua. Most decidual T and natural killer (NK) cells expressed high amounts of the CD54 molecule. Substantially higher numbers of CD3+, CD4+, and CD8+ cells in decidua bore CD11b, whereas the percentage of CD11b-positive NK cells was significantly lower in decidua, compared with that seen in peripheral blood. As opposed to peripheral blood lymphocytes (PBL), phorbol 12-myristate 13-acetate (PMA) stimulation of decidual NK cells elicited a rapid increase in the numbers of CD11b-positive cells but not increased fluorescence intensity of CD11b on the stained cells. The CD54 molecule was also up-regulated on decidual and peripheral blood NK cells but only after 15 hr of stimulation with PMA. In contrast to peripheral blood cells, activation of decidual mononuclear cells by K562 did not lead to an augmentation of the CD11b and CD54 expression on NK lymphocytes. These findings suggest that expression of CAM on DL is regulated in a manner different from that of PBL, and CAM expression may be adapted to accommodate placentation in human beings. The interaction of lymphocytes by means of antigen-independent cell-cell adhesion could be essential for the development of the placenta and the regulation of the local maternal immune response to the genetically foreign fetus.


Assuntos
Moléculas de Adesão Celular/biossíntese , Linfócitos/imunologia , Gravidez/imunologia , Receptores de Retorno de Linfócitos/biossíntese , Antígenos CD/biossíntese , Linhagem Celular , Decídua/imunologia , Feminino , Humanos , Células Matadoras Naturais/imunologia , Selectina L , Ativação Linfocitária , Acetato de Tetradecanoilforbol
17.
J Nat Prod ; 57(8): 1166-71, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7964798

RESUMO

The new triterpene glycoside cucumarioside G2 [1] has been isolated from the sea cucumber Eupentacta fraudatrix. Glycoside 1 is the first triterpene glycoside with the 23,24,25,26,27-pentanorlanostane type of aglycone. Its structure has been established by chemical transformations as well as 13C- and 1H-nmr, eims, and liquid sims studies.


Assuntos
Pepinos-do-Mar/química , Triterpenos/química , Animais , Sequência de Carboidratos , Glicosídeos , Hidrólise , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Sulfatos/química
18.
Toxicon ; 30(11): 1449-56, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1362473

RESUMO

A very potent non-protein toxin was isolated from the sea anemone Radianthus macrodactylus with the use of chromatography on polytetrafluoroethylene, CM-Sephadex C-25 and by cation and anion exchange HPLC. The toxin was identified as palytoxin by u.v.-, i.r.- and 500 MHz 1H NMR spectroscopy. Its LD50 was 0.74 +/- 0.29 micrograms/kg by i.v. injection into mice. So far, palytoxin has been associated with zoanthids only. The toxin caused the loss of haemoglobin from erythrocytes but only in about 2 hr after the beginning of incubation, which is characteristic for palytoxin from zoanthids. Sea anemone palytoxin was divided into major and minor components by HPLC. The latter proved to be a product of degradation of palytoxin.


Assuntos
Acrilamidas , Venenos de Cnidários/análise , Anêmonas-do-Mar/química , Animais , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Venenos de Cnidários/isolamento & purificação , Venenos de Cnidários/toxicidade , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemoglobinas/metabolismo , Dose Letal Mediana , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
19.
Toxicon ; 27(8): 937-45, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2551078

RESUMO

High-angle X-ray diffraction spectra showed that triterpene glycosides form crystalline complexes with membrane cholesterol. Electron microscopy demonstrated a decreased vesicle size, of the membrane preparation from rat brain which is enriched in Na+-K+-ATPase, by the triterpene glycosides. The Arrhenius plot was linear in the presence of triterpene glycosides. The half-width of the phosphatidylcholine N-methyl proton line in proton NMR spectra was not altered in the presence of marine glycosides. The excimer formation of pyrene, a hydrophobic fluorescent probe, was significantly decreased by triterpene glycosides. The increase of tryptophanyl residue fluorescence demonstrated a change of the Na+-K+-ATPase conformation after treatment with cytotoxic glycosides.


Assuntos
Encéfalo/enzimologia , Glicosídeos/farmacologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Triterpenos/farmacologia , Animais , Encéfalo/ultraestrutura , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica , Pirenos/análise , Ratos , Pepinos-do-Mar , Espectrometria de Fluorescência , Temperatura , Triptofano/análise , Difração de Raios X
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