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1.
Georgian Med News ; (274): 164-167, 2018 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-29461247

RESUMEN

The aim of research was to study underground parts of Aconitum orientale Mill and Aconitum nasutum Fisch exReichemb for the composition of biological active diterpenic alkaloids. The research object was underground parts of Aconitum species. Alkaloids sum was received from raw-material which was alkalined beforehand with chloroform extraction. From the results of research we established, that both species of Georgian flora's Aconitum contains alkaloids: lappaconitine, aconitine, karakoline. Underground parts of Aconitum orientale and Aconitum nasutum differ from eath other with composition of alkaloids spectrum. Underground parts of Aconitum orientale contains bases: ranaconitine, gigactonine, licoctonine, but underground parts of Aconitum nasutum contains: talitizamine, kamakonine, aconosine. Alkaloids' summary substances, which were received from underground parts of Aconitum species spread in Georgia, showed selective cytotoxic activity towards A-549 (lung carcinoma), DLD-1 (intestine adenocarcinoma), WS-1 (human normal fibroblasts).


Asunto(s)
Aconitum/química , Alcaloides/farmacología , Antineoplásicos Fitogénicos/farmacología , Raíces de Plantas/química , Células A549 , Aconitina/análogos & derivados , Aconitina/aislamiento & purificación , Alcaloides/clasificación , Alcaloides/aislamiento & purificación , Antineoplásicos Fitogénicos/clasificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cloroformo/química , Diterpenos/aislamiento & purificación , Humanos , Extracción Líquido-Líquido , Especificidad de Órganos , Extractos Vegetales/química
2.
Georgian Med News ; (254): 103-6, 2016 May.
Artículo en Ruso | MEDLINE | ID: mdl-27348177

RESUMEN

Aconitum orientale Mill (family Helleboraceae) is a perennial herb. It is spread in forests of the west and the east Georgia and in the subalpine zone. The research objects were underground parts of Aconitum orientale Mill, which were picked in the phase of fruiting in Borjomi in 2014. We had received alkaloids sum from the air-dry underground parts (1.5 kg) with chloroform extract which was alkalined by 5% sodium carbonate. We received the alkaloids sum of 16.5 g and determined that predominant is pharmacologically active diterpenic alkaloid - Lappaconitine, which is an acting initial part of the antiarrhythmic drug "Allapinin". The chromatospectrophotometrical method of quantitative analysis of Lappaconitine is elaborated for the detection of productivity of the underground parts of Aconitum orientale Mill. It was determined that maximal absorption wave length in ultra-violet spectrum (λmax) is 308 nm; It is established that relative error is norm (4%) from statical processing of quantitative analysis results. We determined that the content of Lappaconitine in the underground parts of Aconitum orientale Mill is 0.11-0.13% in the phase of fruiting. In consequence of experimental data Aconitum orientale Mill is approved as the raw material to receive pharmacologically active Lappaconitine.


Asunto(s)
Aconitina/análogos & derivados , Aconitum/química , Aconitina/análisis , Georgia (República)
3.
Georgian Med News ; (243): 79-81, 2015 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-26087737

RESUMEN

Peganum Harmala L., Peganасеае widely distributed in Georgia. On the basis of chemical analysis of the composition of alkaloids it was found out that the plant contains quinazoline derivatives, among which dominats alkaloid d, 1 peganine: С11Н12NО2, m.p. 198-99ºC (СН3ОН). UV, λmax 275 (lgε 3,95). In IR-spectrum (KBr) 1625 cm- (-N=C) 3200-370 (OH)cm-1 . Mass- spectrum: М+ 171(100%). It was studied the dynamics of accumulation for total alkaloids and d, l - peganine: in the budding phase the amount of alkaloids was - 3,71%, d, l - peganine 0,07÷0,09%; in the phase of mass flowering the sum of alkaloids - 4,51% ,d, l - peganine - 0,1÷0,13%; in the phase of ripeness total alkaloids - 3.92%; d,l - peganine - 0,08÷0,1. The study of specific pharmacological activity showed that the d,l - peganine similar to peganine at a dose of 30 mg/kg causes a decrease in heart rate by 30÷40 beats/min, which is characteristic for anticholinesterases, in parallel with this, a decrease in cholinesterase activity in blood serum has been observed.


Asunto(s)
Alcaloides/farmacología , Colinesterasas/sangre , Peganum/química , Alcaloides/química , Colinesterasas/efectos de los fármacos , Georgia (República) , Humanos
4.
Georgian Med News ; (224): 85-8, 2013 Nov.
Artículo en Ruso | MEDLINE | ID: mdl-24323972

RESUMEN

Vinca roseae L. (Саtharanthus rosea (L.) G. Don) was introduced at Kobuleti experimental station of medical plants. The object of investigation was the plant material of Vinca roseae L. collected in May, 2005., September, 2006 and October, 2009. Total alkaloids were obtained in accordance with Atta- ur-Rachman method. The variability of the quantitative and qualitative composition of total alkaloids and vincaleikoblastin (VLB) fraction during vegetation was studied. It was established that the maximal content of total alkaloids and VLB fraction of Vinca roseae L. is accumulated in the phase of secondary flowering, hence the collecting of a plant material is recommended to be made during the aforesaid vegetation phase as for this period it is a rather high output of a raw material, alkaloid complex and VLB faction. Alkaloids vinkaleikoblastin, ajmalicine and new epimer tetrahydroalstonine with С3Н-α- orientation were yielded, separated and identified using modern physical-chemical and spectral methods (13С NMR).


Asunto(s)
Catharanthus/química , Vinblastina/química , Alcaloides de la Vinca/química , Georgia (República) , Humanos , Vinblastina/aislamiento & purificación , Alcaloides de la Vinca/clasificación , Alcaloides de la Vinca/aislamiento & purificación
5.
Ontogenez ; 43(2): 143-53, 2012.
Artículo en Ruso | MEDLINE | ID: mdl-22650080

RESUMEN

Changes in chromatin structure at different stages of differentiation of human spermatids were studied. It was shown that, in nuclei of early spermatids, chromatin is loosely packed and its structural element is an 8-nm fiber. This "elementary" fiber is predominant at the initial stages of differentiation; in the course of maturation, it is replaced by globular elements approximately 60 nm in diameter. In intermediate spermatids, these globules start to condense into fibrillar aggregates and reduce their diameter to 30-40 nm. At all stages of spermatid maturation, except the final stages, these globules are convergence centers for elementary fibers. This remodelling process is vectored and directed from the apical (acrosomal) to the basal pole of the nucleus. In mature spermatids, the elementary 8-nm fibers are almost absent and the major components are 40-nm fibrillar aggregates. The nuclei of mature spermatids are structurally identical with the nuclei of spermatozoa with the so-called "immature chromatin," which are commonly found in a low proportion in sperm samples from healthy donors and may prevail over the normal cells in spermiogenetic disorders. The cause of this differentiation blockade remains unknown. Possibly, the formation of intermolecular bonds between protamines, which are required for the final stages of chromatin condensation, is blocked in a part of spermatids. The results of this study are discussed in comparison with the known models of nucleoprotamine chromatin organization in human spermatozoa.


Asunto(s)
Diferenciación Celular/genética , Ensamble y Desensamble de Cromatina/fisiología , Cromatina/metabolismo , Espermátides/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/ultraestructura , Cromatina/ultraestructura , Histonas/metabolismo , Humanos , Masculino , Microscopía Electrónica , Protaminas/metabolismo , Espermátides/citología , Espermátides/ultraestructura , Espermatogénesis/fisiología
6.
Mol Biol (Mosk) ; 42(6): 1030-9, 2008.
Artículo en Ruso | MEDLINE | ID: mdl-19140324

RESUMEN

Yeast recombinant plasmid containing FRT-sequence flanked by hybrid GAL-CYC promoter and NPTII gene was developed. GAL-CYC promoter contains four UAS sequences and two closely associated TATA-boxes in CYC part. This construct provides galactose-inducible synthesis of neomycinphosphotransferase from NPTII gene, and, thus, resistance of transformed cells to G418 antibiotic. Nucleosome positioning within NPTII gene in repressed and active states was studied. Under repressive conditions (growth on glucose) stable positioning of three nucleosomes was detected. Two nucleosomes are localized in CYC-part. One of them encompasses both TATA-boxes. The third nucleosome overlaps FRT sequence and start of NPTII gene coding sequence. All three nucleosomes show multiple positioning. It suggests possibility of nucleosome sliding along DNA. After induction of NPTII expression by galactose sliding of two nucleosomes is detected. Sliding leads to exposure of TATA-box and long promoter segment. Sliding results in stable repositioning of nucleosomes at new sites. 5'-distal nucleosome moves closer to UAS-sequences. As a results UAS becomes spatially closer to TATA-box. This proximity facilitates assembly of preinitiation complex. Nucleosomes slides independently from each other. The second nucleosome moves towards FRT-sequence and repositions at its nucleosome positioning signal. Galactose-induced expression does not affect nucleosome positioning with coding region of NPTII gene. Unidirectional sliding and repositioning are detected without induction after deacetylase inhibition with trichostatine A. Basal expression of NPTII gene was shown without activation of GAL-CYC promoter and after spatial uncoupling of coding sequence and promoter by gene inversion. In these cases it seems that expression is driven by TATA-like element in FRT-sequence. This element is located in permanently exposed area (in vivo data).


Asunto(s)
Kanamicina Quinasa/biosíntesis , Nucleosomas/metabolismo , Plásmidos/metabolismo , Elementos de Respuesta/fisiología , Saccharomyces cerevisiae/enzimología , TATA Box/fisiología , Amebicidas/farmacología , Ensamble y Desensamble de Cromatina/efectos de los fármacos , Ensamble y Desensamble de Cromatina/fisiología , Inhibidores Enzimáticos/farmacología , Gentamicinas/farmacología , Ácidos Hidroxámicos/farmacología , Kanamicina Quinasa/genética , Nucleosomas/genética , Plásmidos/genética , Saccharomyces cerevisiae/genética
7.
Biochemistry (Mosc) ; 69(9): 1044-50, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15521819

RESUMEN

It has earlier been shown that multiple positioning of nucleosomes on mouse satellite DNA is determined by its nucleotide sequence. To clarify whether other factors, such as boundary ones, can affect the positionings, we modified the environment of satellite DNA monomer by inserting it into a yeast plasmid between inducible GalCyc promoter and a structural region of the yeast FLP gene. We have revealed that the positions of nucleosomes on satellite DNA are identical to those detected upon reconstruction in vitro. The positioning signal (GAAAAA sequence) of satellite DNA governs nucleosome location at the adjacent nucleotide sequence as well. Upon promoter induction the nucleosome, translationally positioned on the GalCyc promoter, transfers to the satellite DNA and its location follows the positioning signal of the latter. Thus, the alternatives of positioning of a nucleosome on satellite DNA are controlled by its nucleotide sequence, though the choice of one of them is determined by the adjacent nucleosome.


Asunto(s)
ADN Satélite/química , Escherichia coli/metabolismo , Nucleosomas/química , Plásmidos/genética , Saccharomyces cerevisiae/metabolismo , Animales , Secuencia de Bases , ADN Satélite/metabolismo , Escherichia coli/genética , Ratones , Datos de Secuencia Molecular , Nucleosomas/metabolismo , Saccharomyces cerevisiae/genética
8.
Tsitologiia ; 37(9-10): 859-71, 1995.
Artículo en Ruso | MEDLINE | ID: mdl-8815599

RESUMEN

A biochemical and ultrastructural stereo-morphological analysis, with special reference to spatial organization and length of nucleonema and Ag-positive zones, was performed for various modifications of nucleolonemal type nucleoli in normal and regenerating (6 and 22 hours after partial hepatectomy) rat hepatocytes. To determine possible disorders on nucleosomal and supranucleosomal levels, chromatin DNA degradation was carried out during micrococcal nuclease hydrolysis, followed by analysis of electrophoretically separated particles. Functional characterization of intranucleolar chromatin was performed by testing the rate of DNA degradation after DNAase I treatment as well as by detection of free G-C pairs during titration with actinomycin D. Transcriptional activity of nucleoli was determined according to the intensity of [14C]-UTP uptake with isolated nucleoli. It is shown that the total chromatin from control nucleoli contains nucleosomal fibrils, although deprived of high compactization level. Nucleosomes themselves are strongly destabilized. In activated nucleoli structural differences of chromatin are more perceptible. In 6 hour preparations the bulk of chromatin fibrils (about 70%) undergo a further relaxation and lose the nucleosomal structure. Therefore at this point of experiment, the maximum length of nucleolonema and Ag-positive zones was registered in addition to the highest quantity of free G-C pairs, and sensibility to DNAase I transcriptional activity of isolated nucleoli. 22 hours after hepatectomy, the transcriptional activity and functional parameters of intranucleolar chromatin markedly decreased compared to the 6 hour period. Simultaneously, the share of chromatin restituting the nucleosomal structure increased, while the length of nucleolonema was shorter than in nucleoli 6 hours after hepatectomy. The main results could be resumed in the following way: the general composition of nucleolonemal type nucleolus variations described in our experimental conditions is in close relation with the with the compactization grade of ribosomal DNP-fibrils.


Asunto(s)
Nucléolo Celular/ultraestructura , Cromatina/ultraestructura , Regeneración Hepática , Hígado/ultraestructura , Nucleosomas/ultraestructura , Animales , Fraccionamiento Celular , Hepatectomía , Masculino , Microscopía Electrónica , Ratas , Tinción con Nitrato de Plata , Factores de Tiempo , Activación Transcripcional
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