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Liu D, Ma Z, Zhang X, Miao X, Fan L, Zhao L, Wang S, Li G. A metabolomics study: Reveals the protective effect and mechanism of Terminalia chebula Retz on the cardiotoxicity induced by radix Aconiti kusnezoffii Reichb. Pak J Pharm Sci 2021; 34:1233-1241. [PMID: 34602394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
To reveal the protective effect of Terminalia chebula Retz (TCR) on cardiotoxicity induced by radix of Aconitum kusnezoffii Reichb (AKR). Control, AKR, AKR-TCR 1:3, AKR-TCR 1:1, AKR-TCR 3:1 and TCR-prepared AKR groups were set up. After treatment, the heart tissues were observed by H&E staining and transmission electron microscope. Serum myoglobin (MB) and troponin (cTn) were detected by ELISA. UPLC-Q Exactive/MS analysis was performed to detect the metabolic difference among the groups. ELISA results showed that the MB and cTn values of AKR group were significantly higher than Control group (P<0.05), while those of the other groups were lower than AKR group. TCR-prepared AKR group had similar MB and cTn contents to the Control group. Histopathological examination also indicated better detoxifying effects in the TCR-prepared AKR and AKR-TCR 1:1 group. The serum metabolomics analysis showed obvious distinction between the AKR and Control groups, while AKR-TCR combination reversed the metabolomics changes induced by AKR. Through multivariate statistical analysis, 9 metabolic markers related to energy, nucleic acid and amino acid metabolism were identified. Conclusively, AKR-induced cardiotoxicity may be related to energy, nucleic acid and amino acid metabolism, and TCR can reduce the cardiotoxicity by regulating the relative metabolism pathways.
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Affiliation(s)
- Dandan Liu
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China
| | - Zixing Ma
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China
| | - Xiaofei Zhang
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China
| | - Xin Miao
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China
| | - Lei Fan
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China
| | - Lulu Zhao
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China
| | - Shengnan Wang
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China
| | - Gang Li
- Department of Pharmacy, Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, PR China/State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China
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Brunstein J. The challenges of MDx on FFPE tissue. MLO Med Lab Obs 2015; 47:32-33. [PMID: 26302545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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Li SJ, Zhu TH, Zhu HMY, Liang M, Qiao TM, Han S, Che GN. Purification of protein AP-toxin from Arthrinium phaeospermum causing blight in Bambusa pervariabilis × Dendrocalamopisis grandis and its metabolic effects on four bamboo varieties. Phytopathology 2013; 103:135-145. [PMID: 23095467 DOI: 10.1094/phyto-07-12-0164-r] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Bambusa pervariabilis × Dendrocalamopisis grandis blight is caused by a toxin produced by the fungus Arthrinium phaeospermum. In this study, a toxin fraction (P1-2-2) with an estimated molecular mass of 31 kDa was purified from a culture filtrate of this fungus by ammonium sulfate precipitation, Sephadex G-50 gel chromatography, Q Sepharose Fast Flow anion exchange resin, and Sephadex G-75 chromatography. The N-terminal amino acid sequence (i.e., H(2)N-Gln-Val-Arg-Asp-Arg-Leu-Glu-Ser-Thr) determined by Edman degradation showed homology to known serine alkaline proteases. The purified protein was named AP-toxin. Effects of the purified protein toxin on total phenol, flavonoid, total nucleic acid, DNA, RNA, soluble protein, and soluble sugar content, as well as DNase and RNase activities and disease index, were analyzed in different bamboo varieties by the impregnation method. The toxin had a significant effect on each parameter tested. In addition, a significant correlation was observed among the metabolic index, treatment time, bamboo resistance, and disease index. These data suggest that AP-toxin plays an important role in mediating the phytotoxic activities of A. phaeospermum. This study also indicates that metabolic indices could reflect the resistance indices of hybrid bamboo to blight.
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Affiliation(s)
- Shu-Jiang Li
- College of Forestry, Sichuan Agricultural University, Ya'an 625014, China
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Didebuladze NA, Sumbadze TM, Gvidiani SA, Korkiia II. [The influence of the androgens on the process of the experimental diabetes and the activity of the synthesis of the nucleic acids in the male rats liver]. Georgian Med News 2011:61-65. [PMID: 22306504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The aim of this research is to study the dependence the gravity of diabetes course and the activity of the biosynthetical processes in the liver from the level of the sexual steroides in the male-rats blood on the model of the alloxan diabetes. The experiments were carried out on 80 male rats (weight 180-200g). The diabetes has been reproduced by the single injection of alloxan per 200mg/kg. The content of glucose, testosterone, estradiole and corticosterone have been determined in the blood of the animals. Activity of the syntheses of the nucleic acids in the liver has been researched by the radiometrical method on 14, 30, 45 and 90 days of the experiment. On all stages of the observation has been revealed the inverse relation between the concentration of the testosterone in the blood and the gravity of the experimental diabetes which was determined by the degree of hyperglycemya and the changes of the coefficient of sexual hormones ratio, the content of estradiol, corticosterone and activity of the syntheses of the nucleic acids in the tissue of the liver. The injection of the androgen during two week caused jump increasing the testosterone concentration, approaching the sexual steroids ratio to the norm, decreasing the glucose, estradiole, corticosterone content and also the reduction the nucleic acids syntheses activity in the liver. It was shown the positive influence of the androgens on development of the compensatory processes in the male rats, which course the decrease the experimental diabetes gravity.
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Liu ZJ, Lv HN, Li HY, Zhang Y, Zhang HJ, Su FQ, Si YK, Yu SS, Chen XG. Anticancer effect and neurotoxicity of S-(+)-deoxytylophorinidine, a new phenanthroindolizidine alkaloid that interacts with nucleic acids. J Asian Nat Prod Res 2011; 13:400-408. [PMID: 21534037 DOI: 10.1080/10286020.2011.566868] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Phenanthroindolizidine alkaloids are a family of plant-derived compounds with significant antineoplastic activity as well as other effects like antiamebicidal, antiviral, and anti-inflammatory activities. The specific biomolecular targets of these compounds have not yet been clearly identified. S-(+)-Deoxytylophorinidine (CAT) is a new phenanthroindolizidine alkaloid, originally extracted from the roots of Tylophora atrofolliculata and Tylophora ovata. Potent anticancer activity was observed in vitro and in vivo. Neurotoxicity of CAT was also studied and it was far less serious than that of vinblastine. Interactions between this compound and DNA had been studied in detail in our laboratory previously, and we further studied its interactions with RNA.
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Affiliation(s)
- Zhen-Jia Liu
- Department of Pharmacology, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
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Dailey MM, Hait C, Holt PA, Maguire JM, Meier JB, Miller MC, Petraccone L, Trent JO. Structure-based drug design: from nucleic acid to membrane protein targets. Exp Mol Pathol 2009; 86:141-50. [PMID: 19454265 PMCID: PMC3143464 DOI: 10.1016/j.yexmp.2009.01.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2008] [Indexed: 01/08/2023]
Abstract
The in silico methods for drug discovery are becoming increasingly powerful and useful. That, in combination with increasing computer processor power, in our case using a novel distributed computing grid, has enabled us to greatly enhance our virtual screening efforts. Herein we review some of these efforts using both receptor and ligand-based virtual screening, with the goal of finding new anti-cancer agents. In particular, nucleic acids are a neglected set of targets, especially the different morphologies of duplex, triplex, and quadruplex DNA, many of which have increasing biological relevance. We also review examples of molecular modeling to understand receptors and using virtual screening against G-protein coupled receptor membrane proteins.
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Affiliation(s)
- Magdalena M Dailey
- Department of Chemistry, University of Louisville, Louisville, KY 40292, USA
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Moitessier N, Englebienne P, Lee D, Lawandi J, Corbeil CR. Towards the development of universal, fast and highly accurate docking/scoring methods: a long way to go. Br J Pharmacol 2008; 153 Suppl 1:S7-26. [PMID: 18037925 PMCID: PMC2268060 DOI: 10.1038/sj.bjp.0707515] [Citation(s) in RCA: 314] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Revised: 09/18/2007] [Accepted: 09/24/2007] [Indexed: 11/08/2022] Open
Abstract
Accelerating the drug discovery process requires predictive computational protocols capable of reducing or simplifying the synthetic and/or combinatorial challenge. Docking-based virtual screening methods have been developed and successfully applied to a number of pharmaceutical targets. In this review, we first present the current status of docking and scoring methods, with exhaustive lists of these. We next discuss reported comparative studies, outlining criteria for their interpretation. In the final section, we describe some of the remaining developments that would potentially lead to a universally applicable docking/scoring method.
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Affiliation(s)
- N Moitessier
- Department of Chemistry, McGill University, Montréal, Québec, Canada.
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Abstract
Tumor targeting--per definition--includes any strategy to improve the specificity of the therapeutic nucleic acid towards the tumor site, while highest biological activity should be maintained. Targeting has been successfully achieved at the transcriptional, transductional or delivery level. For tumor-specific delivery, physical targeting methods like electroporation, hyperthermia, magnetofection, photochemical internalization or ultrasound, and biological targeting systems, including active and passive tumor targeting, have been developed. Therapeutic effects could be demonstrated with various targeted nucleic acid formulations, such as tumor-targeted DNA plasmids expressing p53 or tumor necrosis factor alpha, small interfering RNAs knocking down gene expression from tumor specific chromosomal translocations or gene expression of tumor neoangiogenic processes, as well as double stranded RNA poly inosine-cytosine which triggers apoptosis in targeted tumor cells.
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Affiliation(s)
- Verena Russ
- Pharmaceutical Biology-Biotechnology, Department of Pharmacy, Ludwig-Maximilians-Universitaet, Munich, Germany
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Al-Majed AA, Al-Yahya AA, Al-Bekairi AM, Al-Shabanah OA, Qureshi S. Studies on the cytological and biochemical effects of valerian in somatic and germ cells of Swiss albino mice. Food Chem Toxicol 2006; 44:1830-7. [PMID: 16879905 DOI: 10.1016/j.fct.2006.06.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Revised: 03/03/2006] [Accepted: 06/02/2006] [Indexed: 01/21/2023]
Abstract
Valerian is widely known for its use as a sedative and an anti-anxiety drug in the folk medicine. Literature reports suggested valerian to induce genotoxicity in vitro (ECV304 cells) by reactive oxygen species-mediated mechanism; however, there are no reports on its genotoxicity and/or the epigenetic mechanism in vivo. In view of the folkloric significance, it was found worthwhile to (1) determine the genotoxic effects of valerian in somatic and germ cells of mice and (2) investigate the role of epigenetic mechanisms. The protocol included the oral treatment of mice with different doses (500, 1000 and 2000 mg/kg/day) of valerian for 7 days. The following experiments were conducted: (i) cytological studies on micronucleus test, (ii) cytogenetic analysis for meiotic chromosomes, (iii) cytological analysis of spermatozoa abnormalities, (iv) quantification of proteins and nucleic acids in testicular cells and (v) estimation of malondialdehyde (MDA) and nonprotein sulfhydryl (NP-SH) in hepatic and testicular cells. The treatment increased the frequency of micronuclei in the polychromatic erythrocytes (PCE) and decrease the ratio of PCE to normochromatic erythrocytes (NCE) in the femur. It caused aberrations in chromosomes of the testis and induced spermatozoa abnormalities. The concentration of nucleic acids was depleted in the testicular cells. These changes might be attributed to the epigenetic mechanisms as revealed by an increase in the concentrations of MDA and a decrease of NP-SH levels in hepatic and testicular cells observed in the present study. The observed changes may be ascribed to terpenoids (valepotriates) and flavonoids (6-methylapigenin and 2S(-)-hesperidin) present in valerian.
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Affiliation(s)
- Abdulhakeem A Al-Majed
- Department of Pharmacology, College of Pharmacy, King Saud University, PO Box 2457, Riyadh-11451, Saudi Arabia.
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Abstract
Aldehydes are organic compounds that are widespread in nature. They can be formed endogenously by lipid peroxidation (LPO), carbohydrate or metabolism ascorbate autoxidation, amine oxidases, cytochrome P-450s, or myeloperoxidase-catalyzed metabolic activation. This review compares the reactivity of many aldehydes towards biomolecules particularly macromolecules. Furthermore, it includes not only aldehydes of environmental or occupational concerns but also dietary aldehydes and aldehydes formed endogenously by intermediary metabolism. Drugs that are aldehydes or form reactive aldehyde metabolites that cause side-effect toxicity are also included. The effects of these aldehydes on biological function, their contribution to human diseases, and the role of nucleic acid and protein carbonylation/oxidation in mutagenicity and cytotoxicity mechanisms, respectively, as well as carbonyl signal transduction and gene expression, are reviewed. Aldehyde metabolic activation and detoxication by metabolizing enzymes are also reviewed, as well as the toxicological and anticancer therapeutic effects of metabolizing enzyme inhibitors. The human health risks from clinical and animal research studies are reviewed, including aldehydes as haptens in allergenic hypersensitivity diseases, respiratory allergies, and idiosyncratic drug toxicity; the potential carcinogenic risks of the carbonyl body burden; and the toxic effects of aldehydes in liver disease, embryo toxicity/teratogenicity, diabetes/hypertension, sclerosing peritonitis, cerebral ischemia/neurodegenerative diseases, and other aging-associated diseases.
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Affiliation(s)
- Peter J O'Brien
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada.
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Abstract
Locked nucleic acid (LNA) is a nucleic acid analog containing one or more LNA nucleotide monomers with a bicyclic furanose unit locked in an RNA-mimicking sugar conformation. This conformational restriction is translated into unprecedented hybridization affinity towards complementary single-stranded RNA molecules. That makes fully modified LNAs, LNA/DNA mixmers, or LNA/RNA mixmers uniquely suited for mimicking RNA structures and for RNA targeting in vitro or in vivo. The focus of this chapter is on LNA antisense, LNA-modified DNAzymes (LNAzymes), LNA-modified small interfering (si)RNA (siLNA), LNA-enhanced expression profiling by real-time RT-PCR and detection and analysis of microRNAs by LNA-modified probes.
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Affiliation(s)
- Volker Erdmann
- Institute of Chemistry/Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Jan Barciszewski
- Institute of Bioorganic Chemistry, Polish Academy of Scienes, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Jürgen Brosius
- Institute of Experimental Pathology, Molecular Neurobiology (ZMBE), University of Münster, Von-Esmarch-Str. 56, 48149 Münster, Germany
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Phe MH, Dossot M, Guilloteau H, Block JC. Nucleic acid fluorochromes and flow cytometry prove useful in assessing the effect of chlorination on drinking water bacteria. Water Res 2005; 39:3618-28. [PMID: 16081129 DOI: 10.1016/j.watres.2005.06.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2004] [Revised: 05/31/2005] [Accepted: 06/01/2005] [Indexed: 05/03/2023]
Abstract
Flow cytometry (FCM), combined with staining using two fluorochromes (propidium iodide, PI, or SYBR Green II RNA gel stain, SYBR-II), was used to assess nucleic acid injuries to chlorinated drinking water bacteria. Highly fluorescent SYBR-II-stained bacteria were converted to bacteria with low fluorescence after chlorination. PI staining of bacteria exposed to different doses of chlorine showed membrane permeabilisation ([Cl2] < 0.2 mg L(-1)) and nucleic acid damage at higher doses ([Cl2] > 0.3 mg L(-1)). Above a threshold dose (between 1.5 and 3 mg Cl2 L(-1)), nucleic acids appeared severely damaged and incapable of being stained by PI or SYBR-II. These results constitute evidence that FCM is a promising tool for assessing drinking water bacteria injuries and for controlling chlorine disinfection efficiency much more rapidly than the standard sensitive but time-consuming heterotrophic plate count method.
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Affiliation(s)
- Meng-Huot Phe
- Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, LCPME UMR 7564 CNRS-UHP, Pôle de l'Eau-15, F-54500 Vandoeuvre-lès-Nancy, France
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Jokhio R, Ansari AF. Cobra snake venom reduces significantly tissue nucleic acid levels in human breast cancer. J PAK MED ASSOC 2005; 55:71-3. [PMID: 15813633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
OBJECTIVE To look into the feasibility of using cobra snake venom in suppressing breast cancer tissue through inhibition of nucleic acid synthesis. METHODS Samples of breast cancerous tissue, obtained from Atomic Energy Medical Center, LMCH, Jamshoro, incubated with varying concentrations of venom and without venom (as controls) were assayed for macromolecular (RNA and DNA) levels RESULTS No. change in the control samples while a prominent and significant fall in nucleic acid contents has been noted in venom treated tissues. Also, maximum effect was observed with 25ug/ml dose. CONCLUSION Snake venom strongly inhibited the formation of nucleic acids in the breast cancerous tissues. It may bring a fall in cell proliferation, thus there is hope that venom could be used as an anti-cancerous drug in the future.
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Csuk R, Raschke C, Göthe G, Reissmann S. Synthesis of dimeric trifluoromethoxyacridine-derived pathogen-inactivating nucleic acid intercalators. Arch Pharm (Weinheim) 2004; 337:571-8. [PMID: 15540226 DOI: 10.1002/ardp.200400907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A series of antiviral active compounds consisting of an intercalating acridine-derived part, a spacer region and a reactive EDTA-derived conjugate was synthesized in an easy sequence. Thus, suitably mono-protected 1,omega-alkyldiamines gave, upon reaction with 9-chloro-2-trifluoromethoxyacridine, followed by deprotection and reaction with EDTA dianhydride, the target molecules. Incorporation of their Fe(II) complexes in the presence of ascorbate gave a reduction of the phage titer of MS2 phages by several logarithmic decades.
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Affiliation(s)
- René Csuk
- Institut für Organische Chemie, Martin-Luther-Universität Halle-Wittenberg, D-06120 Halle (Saale), Germany.
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Csuk R, Barthel A, Brezesinski T, Raschke C. Synthesis of pathogen inactivating nucleic acid intercalators. Eur J Med Chem 2004; 39:975-88. [PMID: 15501547 DOI: 10.1016/j.ejmech.2004.07.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Revised: 07/19/2004] [Accepted: 07/30/2004] [Indexed: 11/22/2022]
Abstract
A series of antiviral compounds consisting of an intercalating acridine derived part, a spacer region and a reactive EDTA-derived conjugate was synthesized in an easy sequence starting from 1,omega-alkyldiamines. As shown in model screenings, in the presence of ascorbic acid the Fe-complexes of these compounds reduced the phage-titer of MS2-phages by several logarithmic decades.
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Affiliation(s)
- René Csuk
- Institut für Organische Chemie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Strasse 2, 06120 Halle (Saale), Germany.
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Han MQ, Liu JX, Gao H, Chen SX, Zhu YW, Xu L. [Effects of Yifei Kangliu Oral Liquid on cell cycle and protein-nucleic acid synthesis of experimental lung cancer]. ACTA ACUST UNITED AC 2004; 1:205-8. [PMID: 15339563 DOI: 10.3736/jcim20030318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To explore the effect of the traditional Chinese medicine Yifei Kangliu (YFKL) Oral Liquid on the proliferation, cell cycle and protein-nucleic acid synthesis of murine Lewis lung cancer cell and human lung adenocarcinoma cell line SPC-A-1. METHODS The inhibiting rates of tumor growth were calculated by weighing the weight of tumor inoculated in vivo, combined by counting cancer cells in vitro. The ratio of the cell cycle and exponents of DNA, RNA, and protein were measured by flow cytometry (FCM). RESULTS The inhibiting rate of tumor growth in the treated group with YFKL Oral Liquid was 30.38% (P<0.05). The proportion of cells in S phase of the treated groups with YFKL Oral Liquid was lower than that of the control group. In the group with most significant result, 72% of the cells were stagnated in G0/G1 phase. The inhibiting rates of DNA, RNA and protein in murine Lewis lung cancer were 7.4%, 23.73% and 23.31% respectively. In SPC-A-1 cell line, the inhibiting rates were 9.3%, 10.1% and 14.7% respectively, demonstrating amplified effects on lower levels. CONCLUSION YFKL Oral Liquid significantly inhibited the proliferation of murine Lewis lung cancer cell and human lung adenocarcinoma cell line SPC-A-1 by blocking the cancer cells entering the proliferative phase resulted from its inhibition of DNA.
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Affiliation(s)
- Ming-Quan Han
- Department of Integrated Traditional Chinese and Western Medicine, Pulmonary Disease Hospital of Shanghai, Shanghai 200433, China.
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Patel M, Agarwal R, Ardalan B. Effects of oxaliplatin and CPT-11 on cytotoxicity and nucleic acid incorporation of the fluoropyrimidines. J Cancer Res Clin Oncol 2004; 130:453-9. [PMID: 15205948 DOI: 10.1007/s00432-004-0575-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2003] [Accepted: 03/25/2004] [Indexed: 11/30/2022]
Abstract
PURPOSE The addition of oxaliplatin or CPT-11 to 5-FU has become common practice in the treatment of colorectal cancer. It is not known, however, which fluoropyrimidine drug (5-FU, FUdR, or FUR) will produce superior cytotoxicity when combined with either oxaliplatin or CPT-11. The purpose of the study was to determine the effects of oxaliplatin and CPT-11 on cytotoxicity and nucleic acid incorporation of all three fluoropyrimidines. METHODS HT-29 cells were exposed for 2 h to IC(10), IC(30), and IC(70) of oxaliplatin and CPT-11. Subsequently, cells were exposed for 24 h to IC(10), IC(30), and IC(70) of 5-FU, FUdR, and FUR. Cytotoxicity was measured by the MTT assay. Nucleic acid incorporation of [(3)H]fluoropyrimidine was then compared in the presence and absence of oxaliplatin or CPT-11 pretreatment. RESULTS Synergistic cytotoxicity was displayed when IC(30) of oxaliplatin or CPT-11 was combined with IC(10) and IC(30) of the fluoropyrimidines. One fluoropyrimidine did not achieve superior cytotoxicity over the others. After pretreatment with oxaliplatin or CPT-11, cytotoxic antagonism was observed as the concentration of a fluoropyrimidine increased up to IC(70). The increasing cytotoxic antagonism correlated with decreases in fluoropyrimidine nucleic acid incorporation. The most significant incorporation difference existed within the 5-FU treated group. CONCLUSIONS No single fluoropyrimidine is more cytotoxically effective over the others when combined with oxaliplatin or CPT-11. Correlation of cytotoxic antagonism to the inhibition of fluoropyrimidine nucleic acid incorporation implies difficulties in drug transport and/or metabolism only after oxaliplatin or CPT-11 pretreatment.
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Affiliation(s)
- Manish Patel
- Division of Hematology and Oncology, Sylvester Comprehensive Cancer Center, University of Miami School of Medicine, 1475 NW 12th Avenue, (D8-4) Rm. 3510, Miami, FL 33136, USA
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Abstract
Investigation of the kinetics of nucleic acid release by HeLa (human cervical carcinoma cell line) and A431 (human squamous carcinoma cell line) cells is presented. The released DNA and RNA were shown to accumulate in culture medium and at the cell surface. A portion of cell surface bound RNA can be eluted with PBS/EDTA. Mild trypsin treatment is required for complete detachment of cell surface bound RNA and cell surface bound DNA. Electrophoretic analysis reveals characteristic patterns of cell-associated and free RNA and DNA molecules.
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Affiliation(s)
- Evgeniy S Morozkin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Division of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
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Jaumot J, Escaja N, Gargallo R, González C, Pedroso E, Tauler R. Multivariate curve resolution: a powerful tool for the analysis of conformational transitions in nucleic acids. Nucleic Acids Res 2002; 30:e92. [PMID: 12202780 PMCID: PMC137437 DOI: 10.1093/nar/gnf091] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A successful application is reported of the multivariate curve resolution alternating least-squares method (MCR-ALS) for the analysis of nucleic acid melting and salt-induced transitions. Under conditions where several structures co-exist in a conformational equilibrium, MCR-ALS analysis of the UV and circular dichroism (CD) spectra at different temperatures, ionic strength and oligonucleotide concentration allows for the resolution of concentration profiles and pure spectra of the different species. The methodology is illustrated by the case of the cyclic oligonucleotide d<pTGCTCGCT>. The melting transition of this molecule at different oligonucleotide concentrations was studied at 0, 2 and 10 mM MgCl2 by UV and CD spectroscopy. In addition, salt titration experiments were carried out at 21.0 and 54.0 degrees C. The MCR-ALS analysis indicates that three different conformations of this molecule co-exist in solution. In agreement with previous NMR studies, these conformations were assigned to a monomeric dumbbell-like structure, a dimeric four-stranded conformation and a disordered (random coil) structure. The MCR-ALS methodology allows for a detailed analysis of how this equilibrium is affected by temperature, salt and oligonucleotide concentration.
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Affiliation(s)
- Joaquim Jaumot
- Departament de Química Analítica, Universitat de Barcelona, Diagonal 647, E-08028, Barcelona, Spain
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20
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Abstract
Much ongoing research in toxicology focuses on a hypothesis-driven mechanism of action approach aimed at understanding the molecular events mediating the actions of the chemicals of interest. Using this approach, investigators develop hypotheses based on observations, which may be derived from a host of resources but most frequently have been made within their own laboratories, or uncovered by others and reported in the scientific literature. Although the bulk of current understanding ofbiochemical toxicology emerged using studies based on observations derived in this way, this process, which is essentially based on existing information, may often limit the expansion knowledge. More simply expressed, one only finds that which one seeks. Without a clear understanding of the processes targeted by a specific toxin the problem of making observations that globally and accurately reflect the events mediating pathology which have been induced by the toxic agent is challenging. Recently, the development of high-throughput technologies for biochemical analysis of gene expression has led to innovative approaches in addressing the problem of making broad-based observations that more accurately reflect the entire spectrum of molecular lesions induced by specific toxins. These strategies include the use of new techniques in analysis of gene expression to convey information on alterations in mRNA levels, one of the earliest cellular signs initiated in response to a potential toxin. Prior to this time studies on toxicant-induced altered gene expression were limited to single, or small numbers of identified genes chosen by an investigator who reasoned, based on an existing observations, that levels of the proteins encoded by these genes were likely to be altered during toxic injury. Now, using cDNA or oligonucleotide genome-wide arrays, toxin-induced alterations in gene expression of thousands of genes can be examined simultaneously. Using these tools, molecular toxicologists can for the first time employ reasoned strategies to make observations, and then formulate hypotheses based on these observations.
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Affiliation(s)
- D E Heck
- Department of Pharmacology, Rutgers University, Piscataway, NJ 08854, USA
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21
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Abstract
[reaction: see text]. Mass spectral data are presented indicating that the antitumor agent 2-crotonyloxymethyl-2-cyclohexenone (COMC) is capable of alkylating oligonucleotides via a mechanism involving an electrophilic exocyclic enone intermediate. Under physiological conditions, the exocyclic enone is likely the glutathionylated 2-exomethylenecyclohexenone. This supports a recent hypothesis that the antitumor activity of COMC arises from alkylation of nucleic acids and/or proteins critical to cell function and not from competitive inhibition of glyoxalase I by an adduct of COMC and glutathione.
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Affiliation(s)
- Qingrong Zhang
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore Maryland 21250, USA
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22
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Munakata H, Kanzaki T, Nakagawa S, Imai H, Uemori Y. Synthesis and nucleic acid-binding properties of water-soluble porphyrins appending platinum(II) complexes. Chem Pharm Bull (Tokyo) 2001; 49:1573-80. [PMID: 11767077 DOI: 10.1248/cpb.49.1573] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We synthesized two water-soluble porphyrins appending platinum(II) complexes [alpha,beta-(4a) and alpha,alpha-(4b) 5,15-bis(2-trans-[PtCl(NH3)2]N-2-aminoethylaminocarbonylphenyl) 2,3,7,8,12,13,17,18-octamethylporphyrin] and studied their reactions with a variety of nucleic acids [disodium adenosine-5'-monophosphate (AMP), disodium guanosine-5'-monophosphate (GMP), disodium thymidine-5'-monophosphate (TMP), disodium cytidine-5'-monophosphate (CMP), synthetic polymer poly(dG)-poly(dC), poly(dA)-poly(dT)] by 1H-NMR, UV-vis and FAB-MS spectroscopies. Based on the denaturation experiments of synthetic nucleic acid polymers, we conclude that the presence of the porphyrins (5.6 microM) does not cause significant changes in the melting temperature of poly(dA)-poly(dT) (28 microM) (deltaT=1 degrees C) and shows reannealing. On the other hand, gradual melting of poly(dG)-poly(dC) (28 microM) occurs at a low temperature (deltaT= -27 degrees C) in the presence of the porphyrins (5.6 microM), and the solutions do not show reannealing phenomena. The results of UV-vis and 1H-NMR experiments revealed that the porphyrins bind to guanine bases and that the porphyrins bind to GMP more strongly than to the other nucleotides. The binding modes between the porphyrins and synthetic nucleic acids are affected more by the coordination of the nucleobase [poly(dG)-poly(dC)] to the Pt(II) in the porphyrins than by Coulomb and hydrophobic interactions.
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Affiliation(s)
- H Munakata
- Faculty of Pharmaceutical Sciences, Hokuriku University, Kanazawa, Japan.
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23
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Arya DP, Coffee RL, Willis B, Abramovitch AI. Aminoglycoside-nucleic acid interactions: remarkable stabilization of DNA and RNA triple helices by neomycin. J Am Chem Soc 2001; 123:5385-95. [PMID: 11389616 DOI: 10.1021/ja003052x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The stabilization of poly(dA).2poly(dT) triplex, a 22-base DNA triplex, and poly(rA).2poly(rU) triple helix by neomycin is reported. The melting temperatures, the association and dissociation kinetic parameters, and activation energies (E(on) and E(off)) for the poly(dA).2poly(dT) triplex in the presence of aminoglycosides and other triplex binding ligands were determined by UV thermal analysis. Our results indicate that: (i) neomycin stabilizes DNA triple helices, and the double helical structures composed of poly(dA).poly(dT) are virtually unaffected. (ii) Neomycin is the most active and triplex-selective stabilization agent among all aminoglycosides, previously studied minor groove binders, and polycations. Its selectivity (DeltaT(m3-->2) vs DeltaT(m2)(-->)(1)) exceeds most intercalating drugs that bind to triple helices. (iii) Neomycin selectively stabilizes DeltaT(m3)(-->)(2) for a mixed 22-base DNA triplex containing C and T bases in the pyrimidine strand. (iv) The rate constants of formation of triplex (k(on)) are significantly enhanced upon increasing molar ratios of neomycin, making triplex association rates closer to duplex association rates. (v) E(on) values become more negative upon increasing concentration of aminoglycosides (paromomycin and neomycin). E(off) values do not show any change for most aminoglycosides except neomycin. (vi) Aminoglycosides can effectively stabilize RNA [poly(rA).2poly(rU)] triplex, with neomycin[being one of the most active ligands discovered to date (second only to ellipticine). (vii) The stabilization effect of aminoglycosides on triple helices is parallel to their toxic behavior, suggesting a possible role of intramolecular triple helix (H-DNA) stabilization by the aminoglycosides.
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Affiliation(s)
- D P Arya
- Laboratory of Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, SC 29634, USA.
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24
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Abstract
Substantial improvement in the safety of blood transfusion has been achieved through the addition of new tests, such as nucleic acid tests, yet residual risk associated with transfusion of blood components persists. Transfusion of blood components has been implicated in the transmission of viruses, bacteria, and protozoa. While it is commonly recognized that hepatitis B virus (HBV), hepatitis C virus (HCV), cytomegalovirus (CMV), and the retroviruses, such as human immunodeficiency virus (HIV) and the human lymphotrophic viruses (HTLV) can be transmitted through cellular components, other pathogens are emerging as potentially significant transfusion-associated infectious agents. For example, transmission of protozoan infections due to trypanosomes and babesia have been reported. In addition to viral and protozoal infectious agents, bacterial contamination of platelet and red cell concentrates continues to be reported; and may be an under-reported transfusion complication. More importantly, new infectious agents may periodically enter the donor population before they can be definitively identified and tested for to maintain consistent safety of the blood supply. The paradigm for this possibility is the HIV pandemic, which erupted in 1979. During the past decade a number of methods to inactivate infectious pathogens in labile blood components have been developed and have entered the advanced clinical trial phase.
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Affiliation(s)
- L Corash
- Cerus Corporation and Department of Laboratory Medicine, University of California, San Francisco, Concord, CA 94520, United States.
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Affiliation(s)
- D J Williams
- Department of Biochemistry, Washington University School of Medicine, Saint Louis, Missouri 63110, USA
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Rivas L, Murza A, Sánchez-Cortés S, García-Ramos JV. Interaction of antimalarial drug quinacrine with nucleic acids of variable sequence studied by spectroscopic methods. J Biomol Struct Dyn 2000; 18:371-83. [PMID: 11149514 DOI: 10.1080/07391102.2000.10506674] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The interaction of antimalarial drug quinacrine (QA) with polynucleotides is studied by UV-visible absorption, fluorescence and surface-enhanced Raman spectroscopy (SERS). The polynucleotides employed for such a study were calf thymus DNA, poly(A).poly(T), poly(A).poly(U), poly(C).poly(G) and poly(dG-dC).poly(dG-dC). Absorption and fluorescence spectra of QA complexes indicate that an interaction with the biomolecule is taking place, although different interaction mechanisms are probable depending on the sequence. The SERS spectra also reflect spectral changes which depend on the polymer sequence and that can be correlated to those observed by fluorescence, with the advantage of the detailed structural information provided by this vibrational technique. QA interacts with polynucleotides through its diprotonated form and by ring stacking. The strength of such interaction is extremely sequence dependent, thus suggesting different interaction mechanisms in each case. The SERS technique allows the simultaneous study of those polynucleotide moieties that are directly involved in the interaction thanks to the short-range character of the SERS spectroscopy. The interaction of QA with the above nucleic acids lead to a different change in the chain stability and flexibility which is further related to the different denaturation tendency of the polymer in the presence of the metal surface.
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Affiliation(s)
- L Rivas
- Instituto de Estructura de la Materia, CSIC, Serrano, Madrid, Spain
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27
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Abstract
In this work the biochemical effects of thioridazine, a commonly used phenothiazine, have been studied upon native double- and single-stranded DNA and also upon a supercoiled plasmid. The results indicate that thioridazine causes damage and scissions to these nucleic acids but only at concentrations much higher than the one used in our cytogenetic experiments and that the damage seems to depend on the concentrations used. Furthermore, we studied the action of thioridazine alone or in combination with caffeine and/or melphalan upon human lymphocytes in vitro. Thioridazine and caffeine (a well-known inhibitor of cellular repair mechanisms) were shown to act synergistically to potentiate the cytogenetic effect of melphalan on human lymphocytes. It is suggested that thioridazine alone or in combination with caffeine may exert its synergistic effect on melphalan cytotoxicity to cultured human lymphocytes not only indirectly, i.e. as a strong calmodulin inhibitor by facilitating the intracellular retention of melphalan, but also directly by reaction with nucleic acids and by causing scissions in and damage to them. Therefore, thioridazine (as chlorpromazine) has some potential as an adjuvant chemotherapeutic agent for the treatment of human cancer.
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Affiliation(s)
- A A Pantazaki
- Laboratory of Biochemistry, Faculty of Chemistry, Aristotle University of Thessaloniki, Greece
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28
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Arce R, Oyola R, Alegría AE. The photobiological differences of gilvocarcins V and M are not related to their transient intermediates and triplet yields. Photochem Photobiol 1998; 68:25-31. [PMID: 9679448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The transient absorption spectra of the intermediates produced by the 355 nm laser excitation of gilvocarcin derivatives have been investigated in various solvents. The spectra consist of a triplet-triplet absorption in the visible region and a residual absorption observed between 340 and 700 nm due to a long-lived species, assigned to the radical cation. A broad-fast decaying band with a maximum at around 700 nm attributed to the solvated electron is also seen in solutions containing a low DMSO/water volume ratio and at 266 nm irradiation of a 50% methanol/water solvent mixture. The molar absorption coefficient of the triplet state of gilvocarcin V (GV) and gilvocarcin M (GM), determined by the energy transfer method, is independent of the solvent properties and has a value of 3.0 x 10(4)/Mcm. The triplet decay rate constants for both drugs are between 1 and 5 x 10(4)/s. A similar initial yield and triplet decay rate constant of GV were observed in the presence of 3.4 mM thymine. Thus, a quenching rate constant of the GV's triplet state by thymine is estimated to be lower than 10(6)/Ms. The triplet quantum yields of both antibiotics determined by using the comparative method are higher in dimethylsulfoxide (DMSO) (0.18) than are those corresponding to 25% DMSO/water (0.06). The decrease in phi T in the presence of water could be attributed to an enhanced internal conversion rate constant from the S1 state or to an increase in the photoionization yield. The similarity of the transient intermediates and their yields for GV and GM suggest that their photobiological differences are due to other factors such as DNA binding constants, preferential localization of the drugs in the cell or the enhanced reactivity of the vinyl group toward cellular components.
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Affiliation(s)
- R Arce
- Department of Chemistry, University of Puerto Rico, Rio Piedras 00931, USA
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29
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Tiagotin IV, Polotskiĭ AE, Vakhitov TI, Tutova II, Rybakova LP. [Experimental study of the biopreparation Lymphotilin as an antiproliferative and antitumor agent]. Vopr Onkol 1998; 44:92-6. [PMID: 9578739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We found in experiments involving the use of a biopreparation lymphotilin that its administration was followed by a decrease in proliferative activity of cultured tumor cells and a longer survival of mice bearing transplantable leukemia. An intensified intercalation of ethidium bromide in nucleic acids of tumor cells in lymphotilin culture points to the drug activity on nuclear level. Tumor cell inhibition by lymphotilin holds much promise for the practice of hematology.
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Affiliation(s)
- Iu V Tiagotin
- State Research Institute of Super Pure Biopreparations, St. Petersburg
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30
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Abstract
The aim of this work was to verify the in vitro virucidal activity of VIRKON No Foam (VIRKON NF) against the HBV DNA, notoriously one the most resistant viruses to heat and to the most commonly used disinfectants. VIRKON NF, an oxidizing agent, has a synergic effect on nucleic acids, polypeptides, glycoproteins, and structural proteins. The experiment was conducted using the serum of a patient with HBsAg+/HBeAg+/HBVDNA+ with a DNA concentration 100 pg/ml. The virucidal activity was tested using the Slot Blot method, the result being evaluated as an inhibition of the autoradiographic signal because of contact of different concentrated solutions and various contact times with the serum. Preliminary tests were carried out after contact of VIRKON NF with serum solutions at 0.1-0.5-1-4% concentrations for a 15 min contact time. VIRKON NF showed an inhibition of autoradiographic signal equal respectively to 0%, 25-50%, 50-70%, 100%. Further experiments were carried out to compare VIRKON NF virucidal activity on HBV to the activity of the most common disinfectants, such as formic aldehyde, Amuchina, glutaraledhyde and phenol. In this way, the infected serum was put into contact with both the most common disinfectant and 1-1.5-2-3-4% VIRKON NF solutions in contact times of 15, 10, 5, 2 min. Using 3% concentrations for a contact time of 10 min, VIRKON NF showed an autoradiographic inhibition signal of 90%. Regarding other disinfectants, only a 2% glutaraldehyde solution for a contact time of 15 min showed similar virucidal activity.
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Affiliation(s)
- D Scioli
- University of Naples Federico II, Department of General and Environmental Physiology, Italy
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31
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Abstract
The semiconductor TiO2 is known to have photobiological activity in prokaryotic and eukaryotic cells. Applications of this photobiological activity have been suggested including sterilization of waste water and phototherapy of malignant cells. Here, several model and cellular systems were used to study the mechanism of photocatalysis by TiO2. Treatment of TiO2 (anatase, 0.45 microns), suspended in water containing a spin trap 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), with UV radiation (320 nm) resulted in an electron spin resonance (ESR) signal characteristic of the hydroxyl radical. Irradiation of solutions containing calf thymus DNA and TiO2 with UVA (320-400 nm) radiation resulted in hydroxylation of guanine bases. The degree of hydroxylation was dependent on both UVA fluence and amount of TiO2 in suspension. Human skin fibroblasts, preincubated 18 h with 10 micrograms/cm2 TiO2 and then UVA-irradiated (0-58 KJ/m2), showed dose dependent photocytoxicity. RNA, isolated from similarly treated fibroblasts, contained significant levels of photooxidation, measured as hydroxylation of guanine bases. However, no oxidative damage was detectable in cellular DNA. These results suggest that nucleic acids are a potential target for photooxidative damage sensitized by TiO2, and support the view that TiO2 photocatalyzes free radical formation.
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Affiliation(s)
- W G Wamer
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Washington, DC 20204, USA.
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32
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Abstract
Escherichia coli K-12 transformed with pA-CYC184 plasmid DNA was exposed to ozone (O3) in aqueous solution. The damage to the membrane, protein, plasmid DNA, and cell survival were investigated. Cell viability was unaffected by short-term O3 exposure (1-5 min) but membrane permeability was compromised as indicated by protein and nucleic acid leakage and lipid oxidation. The intracellular components, protein and DNA, remained intact. With longer durations of O3 exposure (up to 30 min) cell viability decreased with a more significant increase in lipid oxidation and protein and nucleic acid leakage. The proteins leaking out were further oxidized by O3. The total intracellular proteins run on sodium dodecyl sulfate/polyacrylamide gel electrophoresis, and plasmid DNA run on agarose gel, showed progressive degradation corresponding to the decrease in cell viability. The data indicate that membrane components are the primary targets of O3 damage with subsequent reactions involving the intracellular components, protein and DNA.
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Affiliation(s)
- I R Komanapalli
- Department of Microbiology and Molecular Genetics, Loma Linda University, California 92350, USA
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Thornalley PJ. Pharmacology of methylglyoxal: formation, modification of proteins and nucleic acids, and enzymatic detoxification--a role in pathogenesis and antiproliferative chemotherapy. Gen Pharmacol 1996; 27:565-73. [PMID: 8853285 DOI: 10.1016/0306-3623(95)02054-3] [Citation(s) in RCA: 451] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
1. Methylglyoxal is a reactive alpha-oxoaldehyde and physiological metabolite formed by the fragmentation of triose-phosphates, and by the metabolism of acetone and aminoacetone. 2. Methylglyoxal modifies guanylate residues to form 6,7-dihydro-6,7-dihydroxy-6-methyl-imidazo[2,3-b]purine-9(8)one and N2-(1-carboxyethyl)guanylate residues and induces apoptosis. 3. Methylglyoxal modifies arginine residues in proteins to form N(delta)-(4,5-dihydroxy-4-methylimidazolidin-2-yl) ornithine, N(delta)-(5-hydro-5-methylimidazol-4-on-2-yl)ornithine and N(delta)-(5)methylimidazol-4-on-2-yl)ornithine residues. 4. Methylglyoxal-modified proteins undergo receptor-mediated endocytosis and lysosomal degradation in monocytes and macrophages, and induce cytokine synthesis and secretion. 5. Methylglyoxal is detoxified by the glyoxalase system. Decreased detoxification of methylglyoxal may be induced pharmacologically by glyoxalase I inhibitors which have anti-tumor and anti-malarial activities. 6. The modification of nucleic acids and protein by methylglyoxal is a signal for their degradation and may have a role in the development of diabetic complications, atherosclerosis, the immune response in starvation, aging and oxidative stress.
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Affiliation(s)
- P J Thornalley
- Department of Biological and Chemical Sciences, University of Essex, Colchester, UK
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34
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Abstract
The 1,2-diaminobenzene derivation assay for methylglyoxal in biological systems involves the use of perchloric acid, both as a deproteinizing agent and to prevent the spontaneous formation of methylglyoxal from glycolytic pathway intermediates. However, while using a modification of the standard literature assay to measure methylglyoxal in Chinese hamster ovary cells, we found that oxidation of nucleic acids and related compounds by perchloric or trichloroacetic acid results in the formation of methylglyoxal. Compounds containing 2-deoxyribose gave higher levels of methylglyoxal than those containing ribose; purine nucleotides and deoxynucleotides gave more methylglyoxal than did the pyrimidines. Nucleic acids were the most susceptible to degradation, with 12-fold more methylglyoxal being formed from DNA than RNA. Oxidation of nucleic acids increased with higher temperatures and with decreasing nucleic acid fragment size. Another product of nucleic acid oxidation was 2,3-butanedione, the 1,2-diaminobenzene derivative of which is sometimes used as an internal standard during methylglyoxal measurement. Unless accounted for during the assay procedure, the generation of methylglyoxal and 2,3-butanedione due to the oxidation of nucleic acids may lead to substantial errors in the determination of methylglyoxal concentrations in biological systems.
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Affiliation(s)
- F W Chaplen
- Department of Chemical Engineering, University of Wisconsin-Madison 53706, USA
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35
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Haková H, Misúrová E, Kropácová K. The effect of silymarin on concentration and total content of nucleic acids in tissues of continuously irradiated rats. VET MED-CZECH 1996; 41:113-9. [PMID: 8693663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The effect of the hepatoprotective drug silymarin (Flavobion) on the radiation injury of rats continuously irradiated with gamma rays (60Co) was studied. The rats were irradiated during 14 days by the dose rates of 0.2 and 0.6 Gy/day. In the course of irradiation the animals were treated with silymarin twice daily (70 mg/kg p. o. by tube). Silymarin effect was evaluated on the basis of quantitative changes of nucleic acids in the regenerating liver (after 70% hepatectomy), spleen, bone marrow and blood. Silymarin administration in the course of continuous gamma irradiation influenced beneficially the radiation-induced changes of DNA and RNA especially in the bone marrow.
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Affiliation(s)
- H Haková
- P. J. Safárik University, Faculty of Sciences, Kosice, Slovak Republic
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36
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Benton MJ, Nimrod AC, Benson WH. Evaluation of growth and energy storage as biological markers of DDT exposure in sailfin mollies. Ecotoxicol Environ Saf 1994; 29:1-12. [PMID: 7529156 DOI: 10.1016/0147-6513(94)90025-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Direct and indirect measures of growth and energy storage were evaluated as indicators of subchronic 1,1,1-trichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethane (o,p'-DDT) exposure in juvenile sailfin mollies (Poecilia latipinna). Three-day-old mollies were exposed to 0, 1, 10, 25, 50, 75, and 100 micrograms/liter o,p'-DDT for 21 days. Tissue residues, percentage weight gain, RNA and DNA content, RNA:DNA ratio, percentage total lipid, percentage triglyceride, percentage total protein, and triglyceride:total lipid ratio were measured following exposure. Mortality was concentration and time dependent, with 100% mortality at 75 and 100 micrograms/liter. Among controls and remaining treatments, tissue residues (0.50 to 363 ng/mg dry wt), percentage weight gain (116 to 596%), percentage total lipid (2.84 to 4.33%), and percentage triglyceride (1.01 to 3.22%) were significantly different. Tissue residues were positively correlated with concentration, while percentage weight gain, percentage lipid, percentage triglyceride, and triglyceride:total lipid ratio were negatively correlated with concentration. Direct measures are likely to remain the method of choice for evaluating effects of toxicants on growth in laboratory exposures because of their relative simplicity and reliability. However, indirect measures of energy storage, such as triglyceride:total lipid ratio, rather than direct measures of various lipid fractions may be more reliable indicators of the energetic cost of toxicant stress.
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Affiliation(s)
- M J Benton
- Environmental Toxicology Research Program, University of Mississippi, University 38677
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Casazza AM, Long BH. Screening methodologies for the discovery of novel cytotoxic antitumor agents. Biotechnology 1994; 26:281-300. [PMID: 7749307 DOI: 10.1016/b978-0-7506-9003-4.50016-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- A M Casazza
- Department of Experimental Therapeutics, Bristol Myers Squibb Pharmaceutical Research Institute, Princeton, New Jersey, USA
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38
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Affiliation(s)
- J A Murphy
- Department of Chemistry, University of Nottingham, University Park
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Fiala ES, Nie G, Sodum R, Conaway CC, Sohn OS. 2-Nitropropane-induced liver DNA and RNA base modifications: differences between Sprague-Dawley rats and New Zealand white rabbits. Cancer Lett 1993; 74:9-14. [PMID: 7506989 DOI: 10.1016/0304-3835(93)90037-a] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
2-Nitropropane (2-NP), a hepatocarcinogen in male Sprague-Dawley rats but not, under the same conditions, in male New Zealand White rabbits, induces characteristic base modifications in rat liver DNA and RNA including increases in 8-oxoguanine and the formation of 8-aminoguanine. We compared the levels of these modifications in the two animal species at 6, 18 and 42 h after a single i.p. treatment with 1.12 mmol/kg 2-NP. Significantly less nucleic acid base modifications were found to be produced in rabbit liver than in rat liver. Thus, the relative resistance of the rabbit to the hepatocarcinogenicity of 2-NP correlates with decreased levels of 2-NP-induced liver DNA and RNA base damage.
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Affiliation(s)
- E S Fiala
- Division of Biochemical Pharmacology, American Health Foundation, Valhalla, NY 10595
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Cummings J, French RC, Smyth JF. Application of high-performance liquid chromatography for recognition of covalent nucleic acid modification with anticancer drugs. J Chromatogr 1993; 618:251-76. [PMID: 8227259 DOI: 10.1016/0378-4347(93)80037-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Covalent modification of DNA by antineoplastic agents represents a potent biochemical lesion which can play a major role in drug mechanism of action. The ability to measure levels of DNA covalent modifications in target cells in vivo may, therefore, be seen as the ultimate form of therapeutic drug monitoring. Additionally, elucidation of the structure of critical DNA adducts and definition of their role in tumour cell cytotoxicity will provide more selective targets for rational drug design of new cancer chemotherapeutic agents. High-performance liquid chromatography has contributed significantly to all these areas. In vivo levels of nucleic acid covalent modifications are in the range of 1 in 10(5)-10(8) nucleotides precluding the use of conventional high-performance liquid chromatographic detection methods. Several classes of natural product anticancer drugs have been shown to bond covalently to nucleic acids under optimal laboratory conditions. These have proved more accessible to high-performance liquid chromatographic analysis because of their lipophilicity and strong UV chromophores. However, the majority of experimental evidence to date suggests that with the exception of mitomycin C and morpholino-anthracyclines these compounds do not exert their primary mechanism of action through nucleic acid covalent modification. DNA adducts of alkylating and platinating agents are more difficult to detect by high-performance liquid chromatography and can be chemically unstable. These compounds interact with DNA on the basis of chemical kinetics. Thus, the principle sites of attachment tend to be with the most nucleophilic base (guanine) at its most reactive centre (N-7 position). Limited in vivo high-performance liquid chromatographic studies with all classes of anticancer drugs indicate a much more complex pattern of adductation than would have been anticipated from in vitro studies alone. Some of these differences are probably due to methodological artefacts but these studies stress the need for sensitive detection methods and reliable sample preparation (nucleic acid extraction and digestion techniques) when attempting to determine nucleic acid covalent modifications by anticancer drugs.
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Affiliation(s)
- J Cummings
- Imperial Cancer Research Fund, Medical Oncology Unit, Western General Hospital, Edinburgh, UK
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Abstract
In this review, we present various techniques, currently applied in many laboratories, which are useful in the detection of "environmentally"-induced damage to DNA. These techniques include: (a) chromatographic methods, which allow determination of chemical changes within DNA, be they formation of adducts with or oxidation of bases in DNA; (b) electrophoretic methods, which facilitate finding the site(s) in DNA where that chemical modification occurred; and (c) immunological assays, which help to detect DNA damage using externally produced antibodies that recognize the specific chemical changes in DNA or its fragments, as well as by detection of autoantibodies that develop in response to environmental exposures of animals and humans.
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Affiliation(s)
- K Frenkel
- Department of Environmental Medicine, New York University Medical Center, NY 10016-6451
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Kontermann RE, Kobor M, Bautz EK. Identification of a nucleic acid-binding region within the largest subunit of Drosophila melanogaster RNA polymerase II. Protein Sci 1993; 2:223-30. [PMID: 8443600 PMCID: PMC2142351 DOI: 10.1002/pro.5560020211] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The largest and the second-largest subunit of the multisubunit eukaryotic RNA polymerases are involved in interaction with the DNA template and the nascent RNA chain. Using Southwestern DNA-binding techniques and nitrocellulose filter binding assays of bacterially expressed fusion proteins, we have identified a region of the largest, 215-kDa, subunit of Drosophila RNA polymerase II that has the potential to bind nucleic acids nonspecifically. This nucleic acid-binding region is located between amino acid residues 309-384 and is highly conserved within the largest subunits of eukaryotic and bacterial RNA polymerases. A homology to a region of the DNA-binding cleft of Escherichia coli DNA polymerase I involved in binding of the newly synthesized DNA duplex provides indirect evidence that the nucleic acid-binding region of the largest subunit participates in interaction with double-stranded nucleic acids during transcription. The nonspecific DNA-binding behavior of the region is similar to that observed for the native enzyme in nitrocellulose filter binding assays and that of the separated largest subunit in Southwestern assays. A high content of basic amino acid residues is consistent with the electrostatic nature of nonspecific DNA binding by RNA polymerases.
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Affiliation(s)
- R E Kontermann
- Institute of Molecular Genetics, University of Heidelberg, Germany
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43
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Singh V, Kapoor NK, Dhawan BN. Effect of picroliv on protein and nucleic acid synthesis. Indian J Exp Biol 1992; 30:68-9. [PMID: 1506022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Oral administration of picroliv, a standardised fraction of roots and rhizomes of Picrorhiza kurroa, showed stimulation of nucleic acid and protein synthesis in rat liver. Results are comparable with a standard hepatoprotective agent, silymarin.
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Affiliation(s)
- V Singh
- Biochemistry Division, Central Drug Research Institute, Lucknow, India
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44
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Siddiq T, Preedy VR. A comparative study of the effects of the diamine oxidase inhibitor aminoguanidine, with or without dietary restriction, on the nucleic acid and protein composition of cardiac and type I and type II skeletal muscles of the rat. Cell Biochem Funct 1991; 9:201-7. [PMID: 1752025 DOI: 10.1002/cbf.290090308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
It has been proposed that the diamine oxidase inhibitor aminoguanidine may be a potential therapeutically important anabolic agent. An investigation was therefore made into the effects of aminoguanidine treatment with or without nutritional restriction, on cardiac and skeletal muscles containing mainly of either Type I (i.e. soleus) or Type II fibres (i.e. plantaris) or a mixture of Type I and II fibres (i.e. gastrocnemius). After 3 weeks, dietary restrictions reduced cardiac weight, protein, RNA and DNA contents by between 31 per cent and 36 per cent. Similar, but smaller, reductions were observed in the soleus (18-31 per cent), plantaris (22-34 per cent) and gastrocnemius (22-34 per cent). Aminoguanidine had no effect on the heart of the rats fed ad libitum, nor did it alter the response to dietary restriction. Treatment with aminoguanidine had no overt anabolic effect on skeletal muscle, but a reduction in DNA content was observed. It was concluded that cardiac protein and nucleic acid contents are more sensitive to dietary deprivation than either anaerobic or aerobic skeletal muscles. Furthermore, aminoguanidine does not appear to promote growth or reduce catabolism as previous studies have suggested.
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Affiliation(s)
- T Siddiq
- Department of Cardiology, King's College School of Medicine and Dentistry, London, U.K
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Tenchova VB, Pantev TP. [The antiradiation properties of betamide under conditions of sublethal and lethal gamma irradiation]. Radiobiologiia 1991; 31:151-3. [PMID: 1848942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bone marrow cellularity in the femur, mass and cellularity of the spleen and small intestine, and nucleic acid concentration in the leukocyte mass of blood were investigated after the intraperitoneal administration of betamide (500 mg/kg) 15 min before gamma irradiation of mice with doses of 4, 7 and 9 Gy. The number of myelokaryocytes and splenocytes in the protected animals was shown to exceed considerably that in the controls on days 3 and 9 after irradiation with the three doses. With betamide injected on day 9 following irradiation the number of nucleated cells of the small intestine was larger and the nucleic acid concentration in leukocytes higher than the same indices in the irradiated control.
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Derenzini M, Farabegoli F. Selective staining of nucleic acids by osmium-ammine complex in thin sections from lowicryl-embedded samples. J Histochem Cytochem 1990; 38:1495-501. [PMID: 2205645 DOI: 10.1177/38.10.2205645] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Osmium-ammine (OA)/SO2 selectively contrasted RNA- and DNA-containing structures in thin sections from Lowicryl-embedded samples. No cell structures were stained after Epon embedding. RNAse and DNAse digestion experiments demonstrated that only RNA and DNA were stained in Lowicryl thin sections. Protease digestion did not modify the staining reaction. The very fine end-reaction produced a very high resolution of the stained structures. The staining reaction was not due to the presence of SO2 but to the low pH of the solution (ranging from 1.5-2.2). OA in glycine buffer, pH 1.5, selectively contrasted nucleic acids. Electrostatic bonds between nucleic acids and OA complex were probably involved in the staining reaction. Increasing the pH value of the staining medium resulted in loss of OA specificity for nucleic acids. The high electrolyte concentration of the staining medium hindered the staining reaction.
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Affiliation(s)
- M Derenzini
- Dipartimento di Patologia Sperimentale, Università di Bologna, Italy
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47
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Ojha RP, Roychoudhury M, Sanyal NK. Mode of action of intercalators: a theoretical study. Indian J Biochem Biophys 1990; 27:228-39. [PMID: 2286388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Mode of action of some intercalators has been theoretically investigated on the basis of quantum mechanical perturbation method. Energies of H-bond interaction between drug chromophore and base pairs have been calculated in all possible orientations. The stacking energy has also been calculated with the base pairs. The effect of these interactions on specific recognition has also been discussed. On the basis of these studies, a model for the interaction of these drugs has been proposed. This explains the relative activities of acridine intercalators and satisfies the experimental observations.
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Affiliation(s)
- R P Ojha
- Department of Physics, University of Gorakhpur
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Abstract
The transformation of a rat liver epithelial cell line under a wide range of doses of chromium was determined by anchorage-independent growth and tumor formation in syngeneic animals. Chronic exposure to low concentrations and brief exposure to high concentrations of hexavalent chromium (K2CrO4) transformed the cells, but one dose (1 mM K2CrO4, 2 h) was clearly optimal in this regard. The cytotoxicity, effects on cell cycle, rates of chromium uptake, and mutagenic activity under the different treatment conditions were evaluated. The results showed that cells could adapt to the presence of chromium under certain treatment conditions, but this was not the case for the optimal transforming dose. Cells treated with chromium above the optimal transforming dose showed evidence of a transient G2 arrest, whereas all lower levels of treatment did not. A low level continuous exposure to chromate was mutagenic, whereas high level short exposures, including the optimal transforming dose, were not. An increase in the amount of protein complexed with isolated nucleic acids was detected in cells following treatment with the optimal transforming dose of chromate. The results indicate that the effects of chromium on this in vitro system vary with dose, and the identification of those events relevant to metal carcinogenesis will require consideration of treatment conditions.
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Affiliation(s)
- J A Briggs
- Department of Pathology, Vanderbilt University School of Medicine, Nashville, TN 37232
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Dostal LA, Schwetz BA. Determination of diphenhydramine in rat milk and plasma and its effects on milk composition and mammary gland nucleic acids. J Pharm Sci 1989; 78:423-6. [PMID: 2473185 DOI: 10.1002/jps.2600780516] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To study the excretion of diphenhydramine into rat milk, milk and plasma concentrations of diphenhydramine were determined in lactating rats after single or multiple oral doses. Four hours after a single dose of 40 or 100 mg/kg of diphenhydramine, milk concentrations of the drug averaged 0.30 and 2.2 micrograms/mL, respectively, in two experiments, and the milk:plasma ratios ranged from 4.4 to 7.5. Multiple doses did not significantly affect the plasma or milk concentrations or the milk:plasma ratios, which were similar to the theoretical milk:plasma ratio based on pH partitioning for this compound (i.e., 4.0). Although the concentration of diphenhydramine was higher in milk than in plasma, the estimated dose received by the pups (0.057 mg/kg/d) based on the milk concentrations was much lower than that given to the mother. Oral diphenhydramine treatment at doses which significantly reduced maternal food consumption had no effect on milk solid, lipid, protein, or lactose concentrations, nor on mammary gland RNA or DNA content, indicating that diphenhydramine did not adversely affect lactation.
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Affiliation(s)
- L A Dostal
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
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