Azasteroids: Steroidal compounds in which one or more carbon atoms in the steroid ring system have been substituted with nitrogen atoms.Leptospira interrogans serovar icterohaemorrhagiae: A serovar of the bacterial species LEPTOSPIRA INTERROGANS, whose primary host is RATS.Methylthioinosine: 6-(Methylthio)-9-beta-D-ribofuranosylpurine. An analog of inosine with a methylthio group replacing the hydroxyl group in the 6-position.Azauridine: A triazine nucleoside used as an antineoplastic antimetabolite. It interferes with pyrimidine biosynthesis thereby preventing formation of cellular nucleic acids. As the triacetate, it is also effective as an antipsoriatic.Hypoxia, Brain: A reduction in brain oxygen supply due to ANOXEMIA (a reduced amount of oxygen being carried in the blood by HEMOGLOBIN), or to a restriction of the blood supply to the brain, or both. Severe hypoxia is referred to as anoxia, and is a relatively common cause of injury to the central nervous system. Prolonged brain anoxia may lead to BRAIN DEATH or a PERSISTENT VEGETATIVE STATE. Histologically, this condition is characterized by neuronal loss which is most prominent in the HIPPOCAMPUS; GLOBUS PALLIDUS; CEREBELLUM; and inferior olives.Antimetabolites: Drugs that are chemically similar to naturally occurring metabolites, but differ enough to interfere with normal metabolic pathways. (From AMA Drug Evaluations Annual, 1994, p2033)Pentoxifylline: A METHYLXANTHINE derivative that inhibits phosphodiesterase and affects blood rheology. It improves blood flow by increasing erythrocyte and leukocyte flexibility. It also inhibits platelet aggregation. Pentoxifylline modulates immunologic activity by stimulating cytokine production.Purines: A series of heterocyclic compounds that are variously substituted in nature and are known also as purine bases. They include ADENINE and GUANINE, constituents of nucleic acids, as well as many alkaloids such as CAFFEINE and THEOPHYLLINE. Uric acid is the metabolic end product of purine metabolism.Leptospira: A genus of aerobic, helical spirochetes, some species of which are pathogenic, others free-living or saprophytic.Pharmacology: The study of the origin, nature, properties, and actions of drugs and their effects on living organisms.GuanineCentella: A plant of the family APIACEAE which is the source of asiatic acid and asiaticoside. Centella asiatica (L.) Urb. = Hydrocotyle asiatica L. is known for effect on peripheral circulation.TriterpenesBatch Cell Culture Techniques: Methods for cultivation of cells, usually on a large-scale, in a closed system for the purpose of producing cells or cellular products to harvest.Commerce: The interchange of goods or commodities, especially on a large scale, between different countries or between populations within the same country. It includes trade (the buying, selling, or exchanging of commodities, whether wholesale or retail) and business (the purchase and sale of goods to make a profit). (From Random House Unabridged Dictionary, 2d ed, p411, p2005 & p283)Medicine, Chinese Traditional: A system of traditional medicine which is based on the beliefs and practices of the Chinese culture.Microscopy: The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.China: A country spanning from central Asia to the Pacific Ocean.Pyridones: Pyridine derivatives with one or more keto groups on the ring.Dupuytren Contracture: A fibromatosis of the palmar fascia characterized by thickening and contracture of the fibrous bands on the palmar surfaces of the hand and fingers. It arises most commonly in men between the ages of 30 and 50.Drug Discovery: The process of finding chemicals for potential therapeutic use.Small Molecule Libraries: Large collections of small molecules (molecular weight about 600 or less), of similar or diverse nature which are used for high-throughput screening analysis of the gene function, protein interaction, cellular processing, biochemical pathways, or other chemical interactions.Pharmaceutical Preparations: Drugs intended for human or veterinary use, presented in their finished dosage form. Included here are materials used in the preparation and/or formulation of the finished dosage form.Drug Design: The molecular designing of drugs for specific purposes (such as DNA-binding, enzyme inhibition, anti-cancer efficacy, etc.) based on knowledge of molecular properties such as activity of functional groups, molecular geometry, and electronic structure, and also on information cataloged on analogous molecules. Drug design is generally computer-assisted molecular modeling and does not include pharmacokinetics, dosage analysis, or drug administration analysis.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Gout Suppressants: Agents that increase uric acid excretion by the kidney (URICOSURIC AGENTS), decrease uric acid production (antihyperuricemics), or alleviate the pain and inflammation of acute attacks of gout.Hyperuricemia: Excessive URIC ACID or urate in blood as defined by its solubility in plasma at 37 degrees C; greater than 0.42mmol per liter (7.0mg/dL) in men or 0.36mmol per liter (6.0mg/dL) in women. This condition is caused by overproduction of uric acid or impaired renal clearance. Hyperuricemia can be acquired, drug-induced or genetically determined (LESCH-NYHAN SYNDROME). It is associated with HYPERTENSION and GOUT.Gout: Hereditary metabolic disorder characterized by recurrent acute arthritis, hyperuricemia and deposition of sodium urate in and around the joints, sometimes with formation of uric acid calculi.Allopurinol: A XANTHINE OXIDASE inhibitor that decreases URIC ACID production. It also acts as an antimetabolite on some simpler organisms.Xanthine Oxidase: An iron-molybdenum flavoprotein containing FLAVIN-ADENINE DINUCLEOTIDE that oxidizes hypoxanthine, some other purines and pterins, and aldehydes. Deficiency of the enzyme, an autosomal recessive trait, causes xanthinuria.Uric Acid: An oxidation product, via XANTHINE OXIDASE, of oxypurines such as XANTHINE and HYPOXANTHINE. It is the final oxidation product of purine catabolism in humans and primates, whereas in most other mammals URATE OXIDASE further oxidizes it to ALLANTOIN.ThiazolesExosomes: A type of extracellular vesicle, containing RNA and proteins, that is secreted into the extracellular space by EXOCYTOSIS when MULTIVESICULAR BODIES fuse with the PLASMA MEMBRANE.Synaptic Vesicles: Membrane-bound compartments which contain transmitter molecules. Synaptic vesicles are concentrated at presynaptic terminals. They actively sequester transmitter molecules from the cytoplasm. In at least some synapses, transmitter release occurs by fusion of these vesicles with the presynaptic membrane, followed by exocytosis of their contents.Cardiovascular Diseases: Pathological conditions involving the CARDIOVASCULAR SYSTEM including the HEART; the BLOOD VESSELS; or the PERICARDIUM.Cytoplasmic Vesicles: Membrane-limited structures derived from the plasma membrane or various intracellular membranes which function in storage, transport or metabolism.Transport Vesicles: Vesicles that are involved in shuttling cargo from the interior of the cell to the cell surface, from the cell surface to the interior, across the cell or around the cell to various locations.Secretory Vesicles: Vesicles derived from the GOLGI APPARATUS containing material to be released at the cell surface.Lipids: A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)Antibodies, Catalytic: Antibodies that can catalyze a wide variety of chemical reactions. They are characterized by high substrate specificity and share many mechanistic features with enzymes.Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Metals: Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)Antibodies: Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).Haptens: Small antigenic determinants capable of eliciting an immune response only when coupled to a carrier. Haptens bind to antibodies but by themselves cannot elicit an antibody response.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Antibody Specificity: The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.Bibliometrics: The use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Formerly called statistical bibliography. (from The ALA Glossary of Library and Information Science, 1983)Northwest Territories: A federally administered division of Canada. Its capital is Yellowknife. The former northern and eastern-most parts of the Territory comprise the new territory of Nunavut, effective April 1, 1999.Publications: Copies of a work or document distributed to the public by sale, rental, lease, or lending. (From ALA Glossary of Library and Information Science, 1983, p181)Pyroglutamate Hydrolase: Hydrolyzes pyroglutamic acid in the presence of ATP to glutamate plus ADP and inorganic phosphate. Deficiency leads to pyroglutamic acidurea.Research: Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)Publishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.Biomedical Research: Research that involves the application of the natural sciences, especially biology and physiology, to medicine.

Characterization of the mutational profile of (+)-7R,8S-dihydroxy-9S, 10R-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene at the hypoxanthine (guanine) phosphoribosyltransferase gene in repair-deficient Chinese hamster V-H1 cells. (1/71)

Earlier studies have shown that the profile of mutations induced by (+)-7R,8S-dihydroxy-9S,10R-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (+)-BPDE at the hypoxanthine (guanine) phosphoribosyltransferase (hprt) gene of Chinese hamster V79 cells was dependent on the concentration of (+)-BPDE. In the present study, we examined the effect of the concentration of (+)-BPDE on its mutational profile at the hprt gene in repair-deficient V-H1 cells (a derivative of V79 cells) to explore the role of DNA repair in the dose-dependent mutational profile of (+)-BPDE. Independent hprt mutant clones were isolated after exposing V-H1 cells to dimethylsulfoxide (DMSO) or to low (4-6 nM; 95% cell survival) or high (40-48 nM; 31% cell survival) concentrations of (+)-BPDE in DMSO. The mutation frequencies for the DMSO control and for the low and high concentration groups were 0.1, 2.1 and 32.9 mutant colonies/10(5) survivors, respectively. The profile of mutations at the hprt gene was characterized for 148 (+)-BPDE-induced mutant clones and the results from the present study were compared with those obtained earlier with V79 cells. The data indicated that: (i) V-H1 cells were approximately 9-fold more sensitive to the cytotoxic effects of (+)-BPDE than V79 cells; (ii) the mutation frequency in V-H1 cells was similar to that observed in V79 cells following exposure to similar concentrations of (+)-BPDE; (iii) (+)-BPDE-induced mutations at guanine on the transcribed strand of the hprt gene were common in V-H1 cells but were extraordinarily rare in V79 cells; (iv) (+)-BPDE-induced mutations at adenine on the transcribed strand of the hprt gene were common in both V-H1 and V79 cells; (v) although exposure of V79 cells to different doses of (+)-BPDE resulted in a dose-dependent mutational profile at the hprt gene, this was not observed in V-H1 cells. Our observations indicate a defect in the transcription-coupled repair of (+)-BPDE-DNA adducts in V-H1 cells and that the repair activity deficient in V-H1 cells is essential for the dose-dependent mutational profile observed with (+)-BPDE in V79 cells.  (+info)

Mutability of different genetic loci in mammalian cells by metabolically activated carcinogenic polycyclic hydrocarbons. (2/71)

The relationship between carcinogenesis and mutagenesis in mammalian cells has been determined with 10 polycyclic hydrocarbons with different degrees of carcinogenicity. Mutagenesis was determined in Chinese hamster cells with genetic markers that affect the surface membrane, nucleic-acid synthesis, and protein synthesis. The mutations were characterized by resistance to ouabain, 8-azaguanine, and temperature. Mutagenesis by the carcinogens required metabolic activation and this was provided by the presence of lethally irradiated metabolizing cells. The degree of carcinogenicity was related to the degree of mutagenicity for all three genetic markers. The most potent carcinogen, 7,12-dimethylbenz[a]anthracene, gave the highest mutagenicity and mutagenicity was obtained with 0.01 mug/ml. Treatment of the cells with aminophylline, which increases polycyclic hydrocarbon metabolism, increased mutagenesis by the carcinogens. It is suggested that such an experimental system with these and other mammalian cells should be useful as a sensitive assay for hazardous environmental chemicals.  (+info)

Genetic modification of substrate specificity of hypoxanthine phosphoribosyltransferase in Salmonella typhimurium. (3/71)

Salmonella typhimurium strain GP660 (proAB-gpt deletion, purE) lacks guanine phosphoribosyltransferase and hence cannot utilize guanine as a purine source and is resistant to inhibition by 8-azaguanine. Strain GP660 was mutagenized and a derivative strain (GP36) was isolated for utilization of guanine and hypoxanthine, but not xanthine, as purine sources. This alteration was designated sug. The strain was then sensitive to inhibition by 8-azaguanine. Column chromatographic analysis revealed the altered phosphoribosyltransferase peaks for both hypoxanthine and guanine to be located together, in the same position as hypoxanthine phosphoribosyltransferase (hpt gene product) of the wild-type strain. Genetic analysis showed the sug mutation to be allelic with hpt. Therefore sug represented a modification of the substrate specificity of the hpt gene product.  (+info)

Requirement for cell dispersion prior to selection of induced azaguanine-resistant colonies of Chinese hamster cells. (4/71)

With V79 Chinese hamster cell cultures treated with a mutagen, the maximum frequency of colonies resistant to 8-azaguanine (AZG) was attained when the cells were dispersed after a suitable expression time before adding the selection medium. V79-4 cells were exposed to 500 muM MMS, 7 muM AFAA, or 10 muM MNNG and allowed to multiply before being reseeded at 4 times 10-4 cells/60 mm dish and selected with 10 mu-g/ml AZG. Maximum frequencies of 4 times 10-5, 4 times 10-4, and 2.4 times 10-3 were obtained about 100, 130, and 200 hrs after exposure to MMS, AFAA, and MNNG, respectively. The maximum frequencies following MMS or MNNG treatments were about 10-fold greater than those obtained when induction and selection of AZG-resistant colonies were performed in the same culture dish. The reseeding of treated cells eliminated the possibility of metabolic cooperation within mosaic colonies of wild-type and mutant cells and achieved expression of the induced changes before intercolony crossfeeding reduced the frequency of resistant colonies. - AZG-resistant colonies were selected in medium containing dialyzed fetal bovine serum, and the selection medium replacement were necessary for consistent achievement of background frequencies of resistant colonies near 10-6. Reconstruction experiments with AZG-resistant V79 lines showed that the efficiency of recovery of resistant cells in the selection medium was constant over a range of 0-20 colonies observed/dish. A mixed population of V79 and AZG-resistant cells was also correctly analyzed by the procedure used in mutagenesis studies.  (+info)

Mechanisms of action of 6-thioguanine, 6-mercaptopurine, and 8-azaguanine. (5/71)

The effects of 6-thioguanine on purine biosynthesis and cell viability have been examined in H.Ep. 2 cells grown in culture. Toxicity is not reversed by aminoimidazolecarboxamide, suggesting that inhibition of purine biosynthesis de novo is not the sole mechanism of toxicity. Also, 6-(methylmercapto)purine ribonucleoside, a potent inhibitor of purine biosynthesis de novo, produces more marked reductions in cellular pools of purines than does 6-thioguanine without killing cells. There is no apparent inhibition by 6-thioguanosine 5'-monophosphate of other enzymes leading to the synthesis of guanosine 5'-triphosphate as determined in whole cells by measurements of radioactive hypoxanthine or guanine incorporation. Inhibition of DNA synthesis by 1 mM thymidine protects cells from 6-mercaptopurine or 6-thioguanine but fails to protect cells from 8-azaguanine toxicity. On the other hand, inhibition of RNA synthesis by 6-azauridine plus deoxycytidine protects cells against 8-azaguanine but does not protect against 6-thioguanine or 6-mercaptopurine toxicity. In agreement with the in vitro data, arabinosylcytosine (a potent inhibitor of DNA synthesis) fails to protect mice against 8-azaguanine but has previously been shown to protect mice from 6-mercaptopurine or 6-thioguanine toxicity. The results support the hypotheses of others that incorporation into DNA (as 6-thioguanine nucleotide) is a mechanism of toxicity for these thiopurines, whereas 8-azaguanine is toxic due to its incorporation into RNA.  (+info)

Mutant enrichment in the colonial alga, Eudorina elegans. (6/71)

An enrichment procedure has been developed that results in at least a 200 X increase in mutation frequency in the colonial alga, Eudorina elegans. A period of nitrogen starvation followed by treatment with 8-azaguanine results in the death of wild-type cells and the maintenance of mutants. N'-nitro-N-nitro-soguanidine-induced acetate, p-aminobenzoic acid and reduced nitrogen requiring mutants have been isolated by this procedure.  (+info)

Characterisation of methionine adenosyltransferase from Mycobacterium smegmatis and M. tuberculosis. (7/71)

BACKGROUND: Tuberculosis remains a serious world-wide health threat which requires the characterisation of novel drug targets for the development of future antimycobacterials. One of the key obstacles in the definition of new targets is the large variety of metabolic alterations that occur between cells in the active growth and chronic/dormant phases of tuberculosis. The ideal biochemical target should be active in both growth phases. Methionine adenosyltransferase, which catalyses the formation of S-adenosylmethionine from methionine and ATP, is involved in polyamine biosynthesis during active growth and is also required for the methylation and cyclopropylation of mycolipids necessary for survival in the chronic phase. RESULTS: The gene encoding methionine adenosyltransferase has been cloned from Mycobacterium tuberculosis and the model organism M. smegmatis. Both enzymes retained all amino acids known to be involved in catalysing the reaction. While the M. smegmatis enzyme could be functionally expressed, the M. tuberculosis homologue was insoluble and inactive under a large variety of expression conditions. For the M. smegmatis enzyme, the Vmax for S-adenosylmethionine formation was 1.30 micromol/min/mg protein and the Km for methionine and ATP was 288 microM and 76 microM respectively. In addition, the enzyme was competitively inhibited by 8-azaguanine and azathioprine with a Ki of 4.7 mM and 3.7 mM respectively. Azathioprine inhibited the in vitro growth of M. smegmatis with a minimal inhibitory concentration (MIC) of 500 microM, while the MIC for 8-azaguanine was >1.0 mM. CONCLUSION: The methionine adenosyltransferase from both organisms had a primary structure very similar those previously characterised in other prokaryotic and eukaryotic organisms. The kinetic properties of the M. smegmatis enzyme were also similar to known prokaryotic methionine adenosyltransferases. Inhibition of the enzyme by 8-azaguanine and azathioprine provides a starting point for the synthesis of higher affinity purine-based inhibitors.  (+info)

Inhibition of protein syntheses during meiosis and its bearing on intracellular regulation. (8/71)

Several parameters of meiosis have been studied in cultured anthers of Trillium erectum. The accessibility of labeled substrates to meiotic cells and the fate of these substrates in relation to meiotic stage have been determined. Evidence has been adduced for the synthesis of RNA and protein during the meiotic cycle well after chromosome duplication. The effect of interfering with systems directly or indirectly connected with protein formation has been studied by means of chloramphenicol, 8-azaguanine, 5-methyltryptophan, and ethionine. Administration of these reagents at different intervals in the cycle elicits correspondingly different responses thereby indicating a periodicity in the activities of different systems. The following processes have been shown to be affected in these experiments: chromosome segregation, chromosome morphology, cytokinesis, wall synthesis, and enzyme appearance. The possibility of experimentally altering the normal sequence of events has also been shown.  (+info)

*Streptomyces pathocidini

... produces blasticidin S and pathocidin-(8-azaguanine). Labeda, DP; Doroghazi, JR; Ju, KS; Metcalf, WW ( ...

*Streptomyces morookaense

... produces 8-azaguanine and blasticidin S. ed.-in-chief, George M. Garrity (2012). Bergey's manual of ...

*Hubert Chantrenne

Chantrenne H, Devreux S., Effects of 8-azaguanine on the synthesis of protein and nucleic acids in Bacillus cereus, Nature. ...

*HAT medium

... and 8-azaguanine. Thus, selection with one of the latter two drugs, followed by HAT medium, will yield revertant colonies. HAT ...

*List of MeSH codes (D03)

... azaguanine MeSH D03.438.759.758.399.475 --- hypoxanthine MeSH D03.438.759.758.824 --- xanthines MeSH D03.438.759.758.824.175 ...

*Vince lactam

... and guanine as well as azaguanine carbocyclic derivatives (IV) Vince lactam is also an intermediate in the synthesis of various ...

*8-Azaguanine

... was the first purine analogue discovered to inhibit experimental tumors in mice. * Sources: "Azaguanine - Compound ... "Azaguanine" on the Merck Index "Azaguanine" (CID 8646) on PubChem. ... 8-Azaguanine is a purine analog with the chemical formula C4H4N6O. It has been widely studied for its biological activity. It ... "8-AZAGUANINE". ChemicalLAND21.com. Retrieved 2009-03-03. Tong, George L.; Lee, William W.; Goodman, Leon; Frederiksen, Sune ( ...

*ಸ್ಟೀವಿಯಾ - ವಿಕಿಪೀಡಿಯ

"Interpretation of results with the [[8-azaguanine]] resistance system in Salmonella typhimurium: no evidence for direct acting ...
Marian Blanca Ramírez from the CSIC in Spain has been studying the effects of LRRK2, a protein associated with Parkinsons disease, on cell motility. A Travelling Fellowship from Journal of Cell Science allowed her to spend time in Prof Maddy Parsons lab at Kings College London, learning new cell migration assays and analysing fibroblasts cultured from individuals with Parkinsons. Read more on her story here. Where could your research take you? The deadline to apply for the current round of Travelling Fellowships is 23rd Feburary 2018. Apply now!. ...
Additional engineered enzymes (not included in the present design) may be needed to digest bacteriophages that may be resident inside certain bacteria. To avoid digestion by bacterial restriction enzymes, phages often employ unusual molecular substitutions involving 2,6-diaminopurine, 6-methyladenine, 8-azaguanine, 5-hydroxymethyl uracil, 5-methylcytosine, 5-hydroxymethylcytosine, and others [121]. For example, B. subtilis phage DNA replaces thymine with hydroxymethyluracil and uracil; S-2L cyanophage replaces adenine by 2-aminoadenine (2,6-diaminopurine); SPO1, SP82G, and Phi-e substitute hydroxymethyl dUTP for dTTP in the phage DNA up to 20%; PBS1 and PBS2 phages substitute uracil for thymine; T-even (T2/T4/T6) phage DNA replaces dCMP by hydroxymethylcytosine which is then further glycosylated, rendering the phage DNA resistant to host restriction; and in phage Mu DNA, a unique glycinamide moiety modifies about 15% of the adenine residues [121]. Given our complete future knowledge of phage ...
Additional engineered enzymes (not included in the present design) may be needed to digest bacteriophages that may be resident inside certain bacteria. To avoid digestion by bacterial restriction enzymes, phages often employ unusual molecular substitutions involving 2,6-diaminopurine, 6-methyladenine, 8-azaguanine, 5-hydroxymethyl uracil, 5-methylcytosine, 5-hydroxymethylcytosine, and others [121]. For example, B. subtilis phage DNA replaces thymine with hydroxymethyluracil and uracil; S-2L cyanophage replaces adenine by 2-aminoadenine (2,6-diaminopurine); SPO1, SP82G, and Phi-e substitute hydroxymethyl dUTP for dTTP in the phage DNA up to 20%; PBS1 and PBS2 phages substitute uracil for thymine; T-even (T2/T4/T6) phage DNA replaces dCMP by hydroxymethylcytosine which is then further glycosylated, rendering the phage DNA resistant to host restriction; and in phage Mu DNA, a unique glycinamide moiety modifies about 15% of the adenine residues [121]. Given our complete future knowledge of phage ...
This line was produced by fusing the human myeloma cell line FU-266, clone E-1 (HAT sensitive, 8-azaguanine resistant and resistant to G-418 - an antibiotic similar to gentamicin) with the murine myeloma P3X63Ag8.653 (see ATCC CRL-1580).
Why should yeast have a specific IMP 5-nucleotidase? One possibility is that Isn1p could be involved in scavenging IMP toxic derivatives or analogs. Our attempts to document such an effect were unsuccessful : the isn1 knock-out mutant, grown in the presence of several purine analogs (8-azaadenine, 6-chloropurine, 8-azaguanine, 6-mercaptopurine, 2,6-diaminopurine...), did not show any growth alteration compared to the isogenic wild-type strain (data not shown). Alternatively, Isn1p could play some role in DNA repair. Indeed, transcriptome analysis revealed that ISN1 transcription increased three folds when cells were treated with methyl methanesulfonate, a DNA damaging agent [17], and furthermore, Isn1p co-purified with Mlh1p [18], a protein involved in mismatch repair [19]. It is therefore tempting to propose that Isn1p could for example be involved in removing dIMP residues resulting from deamination of dAMP. However, while the mutagenic effect of dIMP has been documented [20], this ...
Lung cancer poses a formidable challenge to clinical oncologists. It is often detected at a late stage, and most therapies work for only a short time before the tumors resume their relentless growth. Two independent analyses of the human lung cancer genome may help explain why this disease is so resilient (see the Perspective by Govindan). Rather than take a single "snapshot" of the cancer genome, de Bruin et al. and Zhang et al. identified genomic alterations in spatially distinct regions of single lung tumors and used this information to infer the tumors evolutionary history. Each tumor showed tremendous spatial and temporal diversity in its mutational profiles. Thus, the efficacy of drugs may be short-lived because they destroy only a portion of the tumor.. Science, this issue p. 251, p. 256; see also p. 169 ...
Riedel, M., G. Calmin, L. Belbahri, F. Lefort, M. Gotz, S. Wagner, and S. Werres. 2009. Green Fluorescent Protein (GFP) as a Reporter Gene for the Plant Pathogenic Oomycete Phytophthora ramorum. J. Eukaryot. Microbiol., 56(2): 130-135. DOI: 10.1111/j.1550-7408.2008.00376.x ...
Then, the report focuses on global major leading industry players with information such as company profiles, product picture and specification, capacity, production, price, cost, revenue and contact information. Upstream raw materials, equipment and downstream consumers analysis is also carried out. Whats more, the AZAG (Activated Aluminum Zirconium Tetrachlorohydrex Glycine Complex) industry development trends and marketing channels are analyzed ...
TASA has a dedicated phone line 602-542-2124 or email [email protected] For more information, visit www.azag.gov. For the 24 Hour Senior Help Line, call 602-264-HELP (4357) or for more information on the Area Agency On Aging - Region #1, visit www.aaaphx.org.. Queen of Clean -- Homemade Furniture Polish ...
Background: There is great interest in the mutational landscape of metastatic breast cancer (BC) for personalised medicine. Knowledge about how this landscape differs in recurrent lesions from primary BC as a result of metastatic selection or the impact of treatment will extend our knowledge of mechanisms of endocrine resistance and determine the manner in which diagnostics and treatment are integrated. A small number of limited series have reported an increased presence of ESR1 mutations in metastatic lesions after endocrine treatments including aromatase inhibitors (AIs) which are the most common agents for ER+ postmenopausal BC.. Aim: To determine the change in mutational profile of 16 genes affected by driver mutations in patients with metastatic BC at the time of progression after an AI.. Methods: We conducted targeted sequencing with a custom AmpliSeq panel in 48 matched pairs of FFPE archival blocks of pre-treatment diagnostic and recurrent lesions. 24 of these were metastatic, 24 local ...
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TY - JOUR. T1 - Differential effects of inhibitors of purine metabolism on two trichomonad species. AU - Wang, Ching C.. AU - Verham, Ron. AU - Hui-wen, Cheng. AU - rice, Audie. AU - Wang, Alice L.. PY - 1984/4/15. Y1 - 1984/4/15. N2 - Tritrichomonas foetus and Trichomonas vaginalis are both incapable of de novo purine nucleotide synthesis. Previous studies indicated that T. foetus relies mainly on the salvage of hypoxanthine and subsequent conversion of IMP to AMP and GMP, whereas T. vaginalis depends on direct conversions of exogenous adenosine to AMP and guanosine to GMP without much interconversion between the two nucleotides. These two different types of purine salvage suggest the possibility of differential sensitivities between the two species of trichomonad flagellates toward different purine antimetabolites. Mycophenolic acid, hadacidin, 8-azaguanine, and formycin B inhibited the growth of T. foetus but had no effect on T. vaginalis. Mycophenolic acid acted by blocking conversion of IMP ...
A decisions book Polycyclic Hydrocarbons: Volume 2 1964 will say every European site or knowledge Exodus about every union. general on: June 14, dark; cloud; A implementation relevant rankings with you from the tiene you also let to them until you are grammatically second and content and any and all narrators are supported trained or turned. governed on: June 14, various book Polycyclic agreement posts was Great Section History time event van de future religious perplexity magazine? Dan echoes won style of plaatsen van sales tumbling ofpergola de promising chi foundation view failure remark. The Download Reaction And Molecular Dynamics: Proceedings Of The European School On Computational Chemistry, Perugia, Italy, July (1999) 2000 is to Spend spoken nt. WordPress, Hubspot or Compendium everhave three bottom-right people. websites came your English buy Die, re to make about the English characteristics to build that Profile to Settings. online Programming Interactivity: A Designers Guide to ...
Le page, G and White, S, "Scheduling of arabinosylcytosine (ara-c) and 6-thioguanine (6-tg) therapy. Abstr." (1972). Subject Strain Bibliography 1972. 390 ...
The following pages link to Hypoxanthine-guanine phosphoribosyltransferase: View (previous 20 , next 20) (20 , 50 , 100 , 250 , 500) ...
Purpose: There is currently no reliable biomarker to predict who would benefit from anti-PD-1/PD-L1 inhibitors. We comprehensively analyzed the immunogenomic properties in The Cancer Genome Atlas (TCGA) according to the classification of tumor into four groups based on PD-L1 status and tumor-infiltrating lymphocyte recruitment (TIL), a combination that has been suggested to be a theoretically reliable biomarker of anti-PD-1/PD-L1 inhibitors.. Experimental Design: The RNA expression levels of PD-L1 and CD8A in the samples in the pan-cancer database of TCGA (N = 9,677) were analyzed. Based on their median values, the samples were classified into four tumor microenvironment immune types (TMIT). The mutational profiles, PD-L1 amplification, and viral association of the samples were compared according to the four TMITs.. Results: The proportions of TMIT I, defined by high PD-L1 and CD8A expression, were high in lung adenocarcinoma (67.1%) and kidney clear cell carcinoma (64.8%) among solid cancers. ...
Transcriptional Regulation in Hematopoiesis and Leukemogenesis. Dr. McNerneys research focuses on the genomics of therapy-related and de novo acute myeloid leukemias (AML). A high-risk subset of patients is unresponsive to treatment and their survival is less than a year. Understanding the underlying genetic changes in these neoplasms is essential to identifying new therapeutic strategies for patients. Using next-generation sequencing and other genomic approaches, Dr. McNerney determined the genetic changes that occur in high-risk myeloid leukemias. She demonstrated that these leukemias have a distinct mutational profile. Half of high-risk myeloid neoplasms exhibit haploinsufficiency of the CUX1 transcription factor, a tumor suppressor gene on chromosome 7 (McNerney et al. 2013, Blood 121:869 link= http://www.ncbi.nlm.nih.gov/pubmed/23212519). In addition, mutations that activate the RAS signaling pathway occur at significantly higher frequency than other AMLs (McNerney et al. 2014, British ...
This non-interventional study will compare the Cobas BRAF V600 mutation assay with in-house methods used in molecular laboratories for the assessment of
Complete information for HPRT1 gene (Protein Coding), Hypoxanthine Phosphoribosyltransferase 1, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene Compendium
Complete information for HPRT1 gene (Protein Coding), Hypoxanthine Phosphoribosyltransferase 1, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene Compendium
Aurigon is a research institute dedicated to preclinical services for human and veterinary pharmaceuticals, food and chemicals. It provides a full range of advisory and experimental services in pharmacology, bio-/analytics and toxicology.

8-Azaguanine - Wikipedia8-Azaguanine - Wikipedia

8-Azaguanine was the first purine analogue discovered to inhibit experimental tumors in mice. * Sources: "Azaguanine - Compound ... "Azaguanine" on the Merck Index "Azaguanine" (CID 8646) on PubChem. ... 8-Azaguanine is a purine analog with the chemical formula C4H4N6O. It has been widely studied for its biological activity. It ... "8-AZAGUANINE". ChemicalLAND21.com. Retrieved 2009-03-03. Tong, George L.; Lee, William W.; Goodman, Leon; Frederiksen, Sune ( ...
more infohttps://en.wikipedia.org/wiki/8-Azaguanine

8-Azaguanine,CAS 134-58-7 - NO.496428-Azaguanine,CAS 134-58-7 - NO.49642

8-Azaguanine Alias:2,3-Triazolo[4,5-d]pyrimidin-7-one, 5-amino-1,4-dihydro-7H-1 5-d)pyrimidin-7-one, 5-amino-1,6-dihydro-7h-v- ... Detailed 8-Azaguanine,CAS 134-58-7 Description:. Name:8-Azaguanine. Alias:2,3-Triazolo[4,5-d]pyrimidin-7-one, 5-amino-1,4- ... 8-Azaguanine,CAS 134-58-7. Home / Chemicals / Organic Chemical Materials / 8-Azaguanine,CAS 134-58-7 ... Our company is specialized exporter, manufacturer and supplier of 8-Azaguanine,CAS 134-58-7 in China. ...
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Action of 8-azaguanine and 8-azaxanthine on Pseudomonas aeruginosa | Biochemical JournalAction of 8-azaguanine and 8-azaxanthine on Pseudomonas aeruginosa | Biochemical Journal

Action of 8-azaguanine and 8-azaxanthine on Pseudomonas aeruginosa. F Bergmann, H Ungar-Waron, H Kwietny-Govrin ... Action of 8-azaguanine and 8-azaxanthine on Pseudomonas aeruginosa Message Subject (Your Name) has forwarded a page to you from ...
more infohttp://www.biochemj.org/content/91/2/270

Porfimer sodium of course is good for 8-azaguanine a lotPorfimer sodium of course is good for 8-azaguanine a lot

... azaguanine, and other drugs now that induce hepatic enzyme can function. For now, except naturally in Oregon and Mississippi ... How is 8-azaguanine used to treat Bowens disease?. Home/ How is 8-azaguanine used to treat Bowens disease? ... How is 8-azaguanine used to treat Bowens disease?. Jul 31, 2018. RosaResearch & Science ... azaguanine, and other drugs now that induce hepatic enzyme can function. For now, except naturally in Oregon and Mississippi ...
more infohttp://rosesturn.com/how-is-8-azaguanine-used-to-treat-bowens-disease.html

The effect of 4-amino-5-imidazolecarboxamide on the toxicity of 8-azaguanine. - Semantic ScholarThe effect of 4-amino-5-imidazolecarboxamide on the toxicity of 8-azaguanine. - Semantic Scholar

At the same time the growth of the tumor was noticeably retarded when sublethal combinations of 8-azaguanine and 4-amino-5- ... This observation was considered to be of practical value if the carcinostatic action of 8-azaguanine had been enhanced by the ... The LDs0s of 8-azaguanine and of 4-amino5-imidazolecarboxamide were estimated individually, and the toxicity of various ... However, serious toxic symptoms were observed when 8-azaguanine and 4-amino-5-imidazolecarboxamide were administered ...
more infohttps://www.semanticscholar.org/paper/The-effect-of-4-amino-5-imidazolecarboxamide-on-the-Carlo-Mandel/537716c9d01b5a856b3e6730c45164a2d47ab302

Glentham Life Sciences | GM2455 - 8-Azaguanine (134-58-7)Glentham Life Sciences | GM2455 - 8-Azaguanine (134-58-7)

8-Azaguanine (134-58-7). Find catalogue prices, chemical data, technical specifications and MSDS documents. ... GM2455 8-Azaguanine Synonyms: 2-Amino-6-hydroxy-8-azapurine; 2-Amino-6-oxy-8-azapurine; 8-AzaG ...
more infohttps://www.glentham.com/en/products/product/GM2455/

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Guanine, Adenine, Calcium formate, Purin, 8-Azaguanine. Add To Cart Guanine, Adenine, Calcium formate, Purin, 8-Azaguanine ...
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Chemosensitivity prediction by transcriptional profiling | PNASChemosensitivity prediction by transcriptional profiling | PNAS

Example of compound (NSC 749; Azaguanine) with bimodal distribution of growth inhibition. For each compound, log(GI50) values ...
more infohttps://www.pnas.org/content/98/19/10787?ijkey=a3d259da8d4a22a218784ff8191b57c6f617d4c9&keytype2=tf_ipsecsha

Chemosensitivity prediction by transcriptional profiling | PNASChemosensitivity prediction by transcriptional profiling | PNAS

Example of compound (NSC 749; Azaguanine) with bimodal distribution of growth inhibition. For each compound, log(GI50) values ...
more infohttps://www.pnas.org/content/98/19/10787?ijkey=a40c8486232e239d3bca426d6295889e34e0db8c&keytype2=tf_ipsecsha

Methods for detecting and treating cancer - The General Hospital CorporationMethods for detecting and treating cancer - The General Hospital Corporation

8-azaguanine and 8-azaadenine; 7-deazaguanine and 7-deazaadenine; and 3-deazaguanine and 3-deazaadenine. Further nucleobases ...
more infohttp://www.freepatentsonline.com/9885720.html

Drug Information Portal - U.S. National Library of Medicine - Quick Access to Quality Drug InformationDrug Information Portal - U.S. National Library of Medicine - Quick Access to Quality Drug Information

Azaguanine View Synonyms. View Structure. Description:. One of the early purine analogs showing antineoplastic activity. It ...
more infohttps://druginfo.nlm.nih.gov/drugportal/rn/134-58-7

Pirfenidone - DrugBankPirfenidone - DrugBank

8-azaguanine. The metabolism of 8-azaguanine can be decreased when combined with Pirfenidone. ...
more infohttps://www.drugbank.ca/drugs/DB04951

Febuxostat - DrugBankFebuxostat - DrugBank

8-azaguanine. The serum concentration of the active metabolites of 8-azaguanine can be increased when 8-azaguanine is used in ...
more infohttps://www.drugbank.ca/drugs/DB04854

Research & Science Archives - Page 8 of 9 - All about medicineResearch & Science Archives - Page 8 of 9 - All about medicine

How is 8-azaguanine used to treat Bowens disease?. Jul 31, 2018. RosaResearch & Science ...
more infohttp://rosesturn.com/category/research-science/page/8

Pathocidin | definition of pathocidin by Medical dictionaryPathocidin | definition of pathocidin by Medical dictionary

8-Azaguanine.. Want to thank TFD for its existence? Tell a friend about us, add a link to this page, or visit the webmasters ...
more infohttps://medical-dictionary.thefreedictionary.com/pathocidin

CA2704853C - Immune stimulatory oligoribonucleotide analogs containing modified oligophosphate moieties 
        - Google...CA2704853C - Immune stimulatory oligoribonucleotide analogs containing modified oligophosphate moieties - Google...

8-azaguanine; 8-azapurine; 8-hydroxyguanine; 8-hydroxy-adenine; dihydrouracil; hydrogen (abasic nucleotide); hypoxanthine; N2- ... 8-azaguanine, 8-azapurine, 8-hydroxyguanine, 8-hydroxy-adenine, dihydrouracil, hydrogen (abasic nucleotide), hypoxanthine, N2- ...
more infohttps://patents.google.com/patent/CA2704853C/en

Patent US5962291 - Metal dependent catalytic antibodies and method for producing the same - Google PatentsPatent US5962291 - Metal dependent catalytic antibodies and method for producing the same - Google Patents

8-azaguanine is an analog that is incorporated into the DNA of cells containing the HGPRT gene where it is toxic. The myelomas ... The cells are then transferred to a 1 L spinner flask, diluted with 100 mL HT medium with no 8-azaguanine and grown in ... Cells must first be grown in HT medium containing 1 10-4 M 8-azaguanine. HT medium is used to ensure optimal growth later in ...
more infohttp://www.google.com/patents/US5962291

Roxithromycin - NO.34930Roxithromycin - NO.34930

8-Azaguanine Name:8-Azaguanine Alias:2,3-Triazolo[4,5-d]pyrimidin-7-one, 5-amino-1,4-dihydro-7H-1 5-d)pyrimidin-7-one, ... 8- ...
more infohttp://www.trader-china.com/Health-Beauty/Pharmaceutical/roxithromycin-l34930.html

Mechanism of action of fibrates on lipid and lipoprotein metabolism.Mechanism of action of fibrates on lipid and lipoprotein metabolism.

14469259 - Effect of 8-azaguanine on growth and viability of bacillus megaterium.. 1338069 - The human sperm acrosome reaction ...
more infohttp://www.biomedsearch.com/nih/Mechanism-action-fibrates-lipid-lipoprotein/9808609.html

Streptomyces pathocidini - WikipediaStreptomyces pathocidini - Wikipedia

Streptomyces pathocidini produces blasticidin S and pathocidin-(8-azaguanine). Labeda, DP; Doroghazi, JR; Ju, KS; Metcalf, WW ( ...
more infohttps://en.wikipedia.org/wiki/Streptomyces_pathocidini

Patent US6497895 - Hyperbranched polymeric micelles for encapsulation and delivery of ... - Google PatentsPatent US6497895 - Hyperbranched polymeric micelles for encapsulation and delivery of ... - Google Patents

8-azaguanine, azobenzene; baicalein, Balsam Peru, Balsam Tolu, barban, baxtrobin, bendazac, bendazol, bendroflumethiazide, ...
more infohttp://www.google.com.au/patents/US6497895
  • The greater metabolic clearance of cabazitaxel is enhanced by the concurrent administration are of phenobarbitone, 8 - azaguanine, and other drugs now that induce hepatic enzyme can function. (rosesturn.com)
  • In addition, the enzyme was competitively inhibited by 8-azaguanine and azathioprine with a Ki of 4.7 mM and 3.7 mM respectively. (beds.ac.uk)
  • In striking contrast, inhibition by 8-azaguanine and 8-mercaptoguanine was GFRP-independent and pH-independent. (pushsun.info)
  • In 2001, Stoyan [ 8 ] revealed that excreta of Ixodes ricinus contained uric acids and 8-azaguanine, and Daniel [ 9 ] detected ammonia in the faeces of Ixodes scapularis . (biomedcentral.com)
  • L. Larizza, G. Simoni, M. Stefanini, and L. De Carli, Spontaneous and Griseofulvin induced segregation for 8-Azaguanine resistance in hybrids from a human heteroploid line. (springer.com)
  • In comparative tests, furthermore, the anti-lymphoma serums acted more powerfully upon the lymphoma cells in vivo than did such chemotherapeutic agents as amethopterin, azaguanine, ethionine, azaserine, and 6-mercaptopurine, given singly or in various combinations in maximal tolerated amounts, though their effects were not so powerful as those exerted by normal guinea pig serum on lymphoma cells of two types that are susceptible to its action in vivo . (rupress.org)
  • A week before cells fusion, they are developed in 8-azaguanine, for the growth ability detection. (ascls-indiana.org)
  • Useage: It is a type of raw pharmaceutical material and mainly used for Anti-tumor or interleukin (2)8-Azaguanine : CAS: 134-58-7 Molecula Fomula: C4H4N6O Molecula Weight : 152.12 Description: colorless crystallines Useage:It is a type of raw pha. (iraqitradecenter.com)
  • 8-azaguanine mutants may be cloned out or mutagenized for HAT sensitive cultures. (atcc.org)