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Morrow J, Amin S, Lake C, Churchill M. Synthesis, structure and dynamic properties of lanthanum(III) complexes of 1,4,7,10-tetrakis(carbamoylalkyl)-1,4,7,10. tetraazacyclododecane. J Inorg Biochem 1993. [DOI: 10.1016/0162-0134(93)85550-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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252
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el-Bayoumy K, Upadhyaya P, Desai DH, Amin S, Hecht SS. Inhibition of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone tumorigenicity in mouse lung by the synthetic organoselenium compound, 1,4-phenylenebis(methylene)selenocyanate. Carcinogenesis 1993; 14:1111-3. [PMID: 8508496 DOI: 10.1093/carcin/14.6.1111] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The chemopreventive effect of 5, 10 and 15 p.p.m. (as selenium) of 1,4-phenylenebis(methylene)selenocyanate (p-XSC) on lung tumor induction by the tobacco-specific 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) was examined in female A/J mice by administering p-XSC in the diet. Sodium selenite (5 p.p.m. selenium) was given in the same manner for comparison with p-XSC. Mice were fed experimental diets containing the selenium compounds 1 week before i.p. injection of 10 mumol NNK in 0.1 ml saline and throughout the experiment until termination, 16 weeks after carcinogen administration. Body weights of the mice in the different dietary groups did not differ significantly. p-XSC significantly inhibited lung tumor multiplicity from 7.6 tumors per mouse in the control group to 4.1, 3.3 and 1.8 tumors per mouse in animals given 5, 10 and 15 p.p.m. of selenium respectively. In contrast, 5 p.p.m. sodium selenite had no protective effect against lung tumor induction. The results of this study clearly indicate that the structure of selenium-containing compounds is important in determining their efficacy as chemopreventive agents.
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Lasker SE, Iatropoulos MJ, Hecht SS, Misra B, Amin S, Zang E, Williams GM. N-ethyl-N-nitrosourea induced brain tumors in rats monitored by nuclear magnetic resonance imaging, plasma proton nuclear magnetic resonance spectroscopy and microscopy. Cancer Lett 1992; 67:125-31. [PMID: 1483261 DOI: 10.1016/0304-3835(92)90135-i] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Characteristic slow growing brain gliomas were induced in rats by a single subcutaneous injection of N-ethyl-N-nitrosourea (ENU) within 24 h of birth. A parallel control group of rats was injected with saline. Seven treated rats developed gliomas within 2 years. Periodic nuclear magnetic resonance imaging (MRI) of the brain in 3-mm slices at 1.5 Tesla and monthly plasma sampling for proton magnetic resonance spectroscopy (MRS) at 360 MHz were started 6 months after the injection of ENU. In the MRS experiments, the Fossel index, average of the line widths of the methylene and methyl peaks at 360 MHz, was determined from half-line widths of methyl and methylene peaks at 0.8 ppm and 1.3 ppm. In five of the ENU injected animals that developed histologically verified brain tumors, these were also observed by MRI without contrast agents. There was no consistent correlation between the imaged tumors and the Fossel index obtained through MRS during the course of the study where repeated observations were performed on individual animals, nor was there any consistent statistical difference in the Fossel index between ENU-treated and control animals. The results of this study demonstrate that slowly developing carcinogen-induced brain tumors in rats can be successfully and reliably monitored noninvasively by MRI but not by MRS of plasma.
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el-Bayoumy K, Desai D, Upadhyaya P, Amin S, Hecht SS. Comparative tumorigenicity of nitrochrysene isomers in newborn mice. Carcinogenesis 1992; 13:2271-5. [PMID: 1473233 DOI: 10.1093/carcin/13.12.2271] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
6-Nitrochrysene (6-NC) is a potent lung and liver carcinogen in the newborn mouse assay. In this report, we extended our studies of the structure--tumorigenicity relationships of the mononitrochrysene isomers. We synthesized 1-NC, 2-NC and 3-NC by oxidation of the corresponding aminochrysenes with mCPBA; efforts to synthesize 4-NC and 5-NC from 4- and 5-aminochrysene were not successful. The tumorigenic activities of 1-NC, 2-NC, 3-NC and 6-NC were compared. Groups of mice were treated with the appropriate compounds in dimethylsulfoxide (DMSO) by i.p. injection on the 1st, 8th and 15th day of life. At a total dose of 100 nmol/mouse, 6-NC induced significant incidences and multiplicities of lung tumors in mice in both sexes; only males were susceptible to liver tumor induction. At 100 nmol/mouse, induction of lung and liver tumors by 1-NC, 2-NC and 3-NC was not significantly different from that observed in mice treated with DMSO. The results indicate that nitro substitution at the 6-position of chrysene is critical for strong tumorigenicity in the newborn mouse assay.
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Rao CV, Desai D, Kaul B, Amin S, Reddy BS. Effect of caffeic acid esters on carcinogen-induced mutagenicity and human colon adenocarcinoma cell growth. Chem Biol Interact 1992; 84:277-90. [PMID: 1423745 DOI: 10.1016/0009-2797(92)90129-9] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Propolis, a honey bee hive product, is thought to exhibit a broad spectrum of activities including antibiotic, antiviral, anti-inflammatory and tumor growth inhibition; some of the observed biological activities may be due to caffeic acid (cinnamic acid) esters that are present in propolis. In the present study we synthesized three caffeic acid esters, namely methyl caffeate (MC), phenylethyl caffeate (PEC) and phenylethyl dimethylcaffeate (PEDMC) and tested them against the 3,2'-dimethyl-4-aminobiphenyl, (DMAB, a colon and mammary carcinogen)-induced mutagenicity in Salmonella typhimurium strains TA 98 and TA 100. Also, the effect of these agents on the growth of human colon adenocarcinoma, HT-29 cells and activities of ornithine decarboxylase (ODC) and protein tyrosine kinase (PTK) was studied. Mutagenicity was induced in Salmonella typhimurium strains TA 98 and TA 100 plus S9 activation using 5 and 10 micrograms DMAB and antimutagenic activities of 0-150 microM MC, 0-60 microM PEC and 0-80 microM PEDMC were determined. The results indicate that MC, PEC and PEDMC were not mutagenic in the Salmonella tester system. DMAB-induced mutagenicity was significantly inhibited with 150 microM MC, 40-60 microM PEC and 40-80 microM PEDMC in both tester systems. Treatment of HT-29 colon adenocarcinoma cells with > 150 microM MC, 30 microM PEC and 20 microM PEDMC significantly inhibited the cell growth and syntheses of RNA, DNA and protein. ODC and PTK activities were also inhibited in HT-29 cells treated with different concentrations of MC, PEC and PEDMC. These results demonstrate that caffeic acid esters which are present in Propolis possess chemopreventive properties when tested in short-term assay systems.
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Misra B, Lin JM, Amin S, Hecht SS. Distinct conformers of alkylchrysene diol epoxide-deoxyguanosine adducts detected by proton NMR. Chem Res Toxicol 1992; 5:756-9. [PMID: 1489924 DOI: 10.1021/tx00030a004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Proton NMR spectra, obtained in MeOH-d4, of the major DNA adduct of 5,7-dimethylchrysene-1,2-diol 3,4-epoxide, identified as 1(R),2(S),3(S)-trihydroxy-4(S)-(N2-deoxyguanosyl)-1, 2,3,4-tetrahydro-5,7-dimethylchrysene, showed the presence of two distinct conformers. One conformer, similar to those observed previously in spectra of peracetates of related DNA adducts of anti-diol epoxides of polynuclear aromatic hydrocarbons, had a chair-like conformation of the tetrahydrobenzo ring. The other conformer, which has not been previously observed, had a boat-like conformation of the tetrahydrobenzo ring. This conformer was converted to the chair-like conformer upon addition of D2O or trifluoroacetic acid to the MeOH-d4 solutions of the adduct. The new conformers were also observed in proton NMR spectra of major DNA adducts of 5-methylchrysene- and 5,6-dimethylchrysene-1,2-diol 3,4-epoxides.
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Lin JM, Desai DH, Morse MA, Amin S, Hecht SS. Inhibition of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone pulmonary metabolism and tumorigenicity in mice by analogues of the investigational chemotherapeutic drug 4-ipomeanol. Chem Res Toxicol 1992; 5:674-9. [PMID: 1446008 DOI: 10.1021/tx00029a013] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
4-Ipomeanol (IPO) is an investigational chemotherapeutic drug with specific toxicity toward the lung. It is metabolically activated to reactive intermediates by cytochrome P450 enzymes present in Clara cells. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a highly carcinogenic tobacco-specific nitrosamine with organo-specificity for the lung. Like IPO, which it resembles structurally, it is metabolically activated by cytochrome P450 enzymes of rat Clara cells. We synthesized nontoxic analogues of IPO and tested their activities as inhibitors of the metabolism and tumorigenicity of NNK. The IPO analogues synthesized were 4-hydroxy-1-phenyl-1-pentanone (HPP), 7-hydroxy-1-phenyl-1-octanone (HPO), 4-hydroxy-1-(2-thienyl)-1-pentanone (HTP), and 4-hydroxy-1-(3-pyridyl)-1-pentanone (HPYP). When added to A/J mouse lung microsomal incubations, all compounds significantly inhibited the oxidative pathways of NNK metabolism--alpha-hydroxylation and pyridine N-oxidation--to varying extents. Inhibition of carbonyl reduction of NNK was generally less effective. Inhibition of alpha-hydroxylation by IPO, HPP, and HTP was more pronounced in incubations with lung microsomes than with liver microsomes. None of the IPO analogues showed significant toxicity when given to A/J mice at a dose of 25 mumol; IPO itself was lethal at this dose. HPP and HPO, at doses of 25 mumol, significantly inhibited lung tumor multiplicity in mice treated with NNK; the other analogues and IPO itself were ineffective. The results of this study provide new leads for development of inhibitors of NNK metabolism and chemical probes for the active site of P450 enzymes in Clara cells.
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Fichtner-Schmittler H, Lutz W, Amin S, Dyer A, Wark M. Hydrothermal damage of ion-exchanged A-type zeolite cation-directed mechanisms of phase transformation. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0144-2449(92)90127-b] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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259
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Murphy SE, Amin S, Coletta K, Hoffmann D. Rat liver metabolism of benzo[b]naphtho[2,1-d]thiophene. Chem Res Toxicol 1992; 5:491-5. [PMID: 1382648 DOI: 10.1021/tx00028a006] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Thioarenes, sulfur-containing polycyclic aromatic hydrocarbons, have been detected in a number of environmental sources. The metabolism of one thioarene, benzo[b]naphtho[2,1,d]thiophene ([2,1]BNT), by F344 rat liver 9000g supernatant (S-9) was studied. [2,1]BNT which is structurally analogous and has similar carcinogenic potency to chrysene, was metabolized to six ethyl acetate-extractable metabolites when incubated with S-9 from Aroclor 1254-treated F344 rats. Each metabolite was collected from reverse-phase HPLC, and their identities were determined by analysis of MS and NMR data. In order of elution from HPLC they are as follows: (1) trans-1,2-dihydroxy-1,2-dihydrobenzo[b]naphtho[2,1-d]thiophene, (2) benzo[b]naphtho[2,1-d]-thiophene sulfone, (3) benzo[b]naphtho[2,1-d]thiophene sulfoxide, (4) trans-3,4-dihydroxy-3,4-dihydrobenzo[b]naphtho[2,1-d]thiophene, (5) 8- or 9-hydroxybenzo[b]naphtho[2,1-d]thiophene, and (6) 7-hydroxybenzo[b]naphtho[2,1-d]thiophene. In addition, the identities of metabolites 1, 2, 3, and 4 were confirmed by comparison to standards. The syntheses of the sulfone and sulfoxide of [2,1]BNT are reported here. The syntheses of the dihydrodiols were reported previously. Metabolite 5, a hydroxy[2,1]BNT, was the major metabolite formed by liver S-9 from untreated F344 rats. Microsomal preparations from these rats also produced significant amounts of the dihydrodiols, 1 and 4, and the sulfoxide, 3. Microsomes prepared from Wistar rats produced dihydrodiols and the sulfone and sulfoxide of [2,1]BNT. Therefore, [2,1]BNT is metabolized by both ring oxidation and sulfur oxidation in these two strains of rats.
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Hunt BJ, Amin S, Halil O, Yacoub M. The prevalence, course, and characteristics of chronic anemia after heart and lung transplantation. Transplantation 1992; 53:1251-6. [PMID: 1604480 DOI: 10.1097/00007890-199206000-00016] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A retrospective study of the 99 surviving heart and lung transplant (HLT) recipients at one center showed that 31% had significant anemia (hemoglobin less than 100g/L) six months after transplantation. Chronic anemia persisted in 18% of HLT recipients two years posttransplantation. A similar study of 100 heart transplant recipients showed no unexplained anemic patients. The prevalence of anemia after HLT was unrelated to the original diagnosis, immunosuppression, or acute rejection. All HLT recipients appeared to be unduly sensitive to the myelosuppressive effects of azathioprine. Detailed studies in 16 representative patients showed a normochromic, anisocytotic anemia with normal reticulocyte counts, B12 and folate levels, and haptoglobin levels and appropriate erythropoietin levels--but increased ESRs, low/normal iron levels and low/normal total iron binding capacity, normal or raised ferritin levels, and autoantibodies in 4 (25%). Bone marrow aspirates in 10 patients showed dyshemopoiesis out of proportion to the degree of anemia and colonies of activated lymphoid cells. The cause for this anemia appears to be a combination of anemia of chronic disease and dyshemopoiesis, both of uncertain etiology.
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Misra B, Amin S, Hecht SS. Dimethylchrysene diol epoxides: mutagenicity in Salmonella typhimurium, tumorigenicity in newborn mice, and reactivity with deoxyadenosine in DNA. Chem Res Toxicol 1992; 5:248-54. [PMID: 1643255 DOI: 10.1021/tx00026a016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In contrast to 5-methylchrysene and 5,9-dimethylchrysene, 5,6-dimethylchrysene and 5,7-dimethylchrysene are weak tumor initiators on mouse skin. In order to investigate the basis for this, we have evaluated the mutagenic activities toward Salmonella typhimurium TA 100 and reactivity with DNA of (+/-)-anti-1,2-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydro-5,6-dimethyl-ch rys ene (anti-5,6-diMeC-1,2-diol 3,4-epoxide) and anti-5,7- and anti-5,9-diMeC-1,2-diol 3,4-epoxide. The tumorigenic activities of anti-5,6- and anti-5,7-diMeC-1,2-diol 3,4-epoxides in newborn mice were also investigated. anti-5,9-diMeC-1,2-diol 3,4-epoxide was the most mutagenic of the three diol epoxides. anti-5,6-diMeC-1,2-diol 3,4-epoxide was highly tumorigenic in newborn mouse lung, with activity significantly greater than that of either anti-5-MeC- or anti-5,7-diMeC-1,2-diol 3,4-epoxide. Although the amounts of total binding of the diol epoxides to calf thymus DNA were similar, anti-5,6-diMeC-1,2-diol 3,4-epoxide bound extensively to deoxyadenosine residues. High binding to deoxyadenosine is related to the presence of a sterically hindered bay or fjord region as present in 5,6-diMeC, 7,12-dimethylbenz[a]anthracene, benzo-[g]chrysene, and benzo[c]phenanthrene. The conformations of the anti- and syn-diol epoxides of 5,6-diMeC and benzo[c]phenanthrene were similar, with both having pseudodiequatorial hydroxyl groups, in contrast to less sterically crowded diol epoxides. The high tumorigenicity of anti-5,6-diMeC-1,2-diol 3,4-epoxide in newborn mice is of interest with respect to its high deoxyadenosine binding.(ABSTRACT TRUNCATED AT 250 WORDS)
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Misra B, Amin S, Hecht SS. Metabolism and DNA binding of 5,6-dimethylchrysene in mouse skin. Chem Res Toxicol 1992; 5:242-7. [PMID: 1643254 DOI: 10.1021/tx00026a015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
5,6-Dimethylchrysene (5,6-diMeC) is a weaker tumor initiator on mouse skin than 5-methylchrysene (5-MeC). To investigate the reasons for the unexpectedly low activity of 5,6-diMeC, we have studied its metabolism and DNA binding in mouse skin, particularly with respect to metabolic activation via its anti-1,2-diol 3,4-epoxide. The metabolism of 5,6-diMeC was first examined with liver 9000g supernatant from Aroclor 1254 pretreated rats. Three major metabolites were identified as 1- or 7-hydroxy-5-(hydroxymethyl)-6-MeC, 1,2-dihydroxy-1,2-dihydro-5,6-diMeC (5,6-diMeC-1,2-diol), and 1-hydroxy-5,6-diMeC. The formation of 5,6-diMeC-1,2-diol was then assessed in mouse epidermis, following topical application of [3H]5,6-diMeC. Levels of 5,6-diMeC-1,2-diol in epidermis exceeded those of 5-MeC-1,2-diol formed from 5-MeC under similar conditions. The binding of [3H]5,6-diMeC and that of [3H]5-MeC to mouse epidermal DNA were then compared. 5,6-DiMeC-deoxyribonucleoside adducts were prepared as markers by reaction of anti- and syn-5,6-diMeC-1,2-diol 3,4-epoxide with calf thymus DNA. HPLC analysis of enzymatic hydrolysates of mouse epidermal DNA, isolated 18 h after topical treatment with [3H]5,6-diMeC or [3H]5-MeC, demonstrated the formation from [3H]5,6-diMeC of two major adducts produced by reaction of its anti-1,2-diol 3,4-epoxide with deoxyguanosine and deoxyadenosine, respectively, while the major adduct formed from [3H]5-MeC resulted from reaction with deoxyguanosine, in agreement with previous results. Total DNA binding of [3H]5-MeC as well as formation of deoxyguanosine adducts exceeded that of [3H]5,6-diMeC by 3-4-fold.(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
In previous studies, we have observed unexpected structure-tumorigenicity relationships among the dimethylchrysenes. Thus, 5,6-dimethylchrysene and 5,7-dimethylchrysene were only weakly tumorigenic and were significantly less active than 5-methylchrysene. These results were surprising in view of the known route of metabolic activation of 5-methylchrysene via its 1,2-diol 3,4-epoxide. In this paper, we extended our studies of structure-tumorigenicity relationships among the dimethylchrysenes. We synthesized 5,7-, 5,8-, 5,9-, and 5,10-dimethylchrysene via photochemical ring closure reactions. The tumor-initiating activities of these dimethylchrysenes on mouse skin were compared with those of 5-methylchrysene and 5,6-dimethylchrysene. 5-Methylchrysene and 5,9-dimethylchrysene were highly tumorigenic and were significantly more active than 5,6-, 5,7-, 5,8-, and 5,10-dimethylchrysene. The results of these studies, taken together with those reported in the subsequent two papers, suggest that the molecular shapes of dimethylchrysenes influence the balance between metabolic activation and detoxification pathways.
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Hunt BJ, Sack D, Amin S, Yacoub MH. The perioperative use of blood components during heart and heart-lung transplantation. Transfusion 1992; 32:57-62. [PMID: 1731437 DOI: 10.1046/j.1537-2995.1992.32192116434.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Perioperative blood usage during 172 heart transplants (HTs) and 100 heart-lung transplants (HTLs) performed at the same center during 1986 and 1989 was reviewed. In 1986, 79 HTs were performed with a median (interquartile range) blood component use of 12 (range, 8-20) units, of which 6 (range, 4-8) constituted red cell components. The use of blood components was significantly reduced (p less than 0.05 by the Mann-Whitney U test) in 1989 to 10 (range, 8-20) units, of which red cell components constituted 5 (range, 3-7) units. Fifty HLTs in 1986 used a median (interquartile range) of 25.5 (range, 11.5-53) units of blood components. This use was significantly reduced (p less than 0.05) to a median of 18 (range, 9-29) units in 1989, of which 8 (range, 5-11) were red cell components, 4 (range, 2-8) were units of fresh-frozen plasma, and 5 (range, 0-10) were units of platelets. More blood components were used in patients who had previous cardiothoracic surgery and/or previous transplants; this reached significance in the 1986 HTs (p less than 0.001). Fresh blood was used in only one HT but in 12 (24%) of 1086 HLTs and 4 (8%) of 1989 HLTs. As the indication for fresh blood was excessive bleeding, there was a significantly greater use of blood components in 1989 HLT patients receiving fresh blood than in those not receiving fresh blood (median [range] of 163.5 [62-251] units compared to 15.5 [3-126]).(ABSTRACT TRUNCATED AT 250 WORDS)
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Rosenberg PA, Amin S, Leitner M. Glutamate uptake disguises neurotoxic potency of glutamate agonists in cerebral cortex in dissociated cell culture. J Neurosci 1992; 12:56-61. [PMID: 1345946 PMCID: PMC6575706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
The pharmacological properties of glutamate agonists were compared in astrocyte-rich and astrocyte-poor cultures derived from embryonic rat cerebral cortex. The object of this investigation was to determine the extent to which glutamate uptake might influence the receptor-mediated neurotoxic actions of these compounds. In astrocyte-rich cultures, using 30 min exposures, we observed that the potencies of the poorly transported agonists NMDA (35 microM) and D-glutamate (89 microM) were higher than that of L-glutamate (205 microM). In astrocyte-poor cultures, L-glutamate was much more potent, with an EC50 of 5 +/- 4 microM (3-12 microM), for a 30 min exposure, whereas the potencies of NMDA and D-glutamate were essentially unchanged. L- and D-aspartate were also more effective in astrocyte-poor cultures, again with EC50 values of approximately 6-10 microM, as compared with 130 and 108 microM, respectively, in astrocyte-rich cultures. In other experiments, blocking sodium-dependent glutamate uptake in astrocyte-rich cultures, by using a sodium-free medium, made glutamate as potent an agonist as in astrocyte-poor cultures. Finally, we directly assessed the glutamate uptake system in astrocyte-rich and astrocyte-poor cultures and found that uptake was reduced approximately 25-fold in the astrocyte-poor cultures. These results show that in the presence of abundant astrocytes the neurotoxic potencies of L-glutamate, L-aspartate, and D-aspartate are substantially under-estimated.
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Majumdar G, Heard SE, Kabarowski JHS, Amin S, Pearson TC. Ph 1Positive Chronic Granulocytic Leukaemia Developing in a Patient with Primary Proliferative Polycythaemia: Case Report and Literature Review. Leuk Lymphoma 1992. [DOI: 10.3109/10428199209053577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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267
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Subbarao EK, Amin S, Kumar ML. Reply. J Infect Dis 1991. [DOI: 10.1093/infdis/164.6.1238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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268
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Pebley AR, Amin S. The impact of a public-health intervention on sex differentials in childhood mortality in rural Punjab, India. HEALTH TRANSITION REVIEW : THE CULTURAL, SOCIAL, AND BEHAVIOURAL DETERMINANTS OF HEALTH 1991; 1:143-69. [PMID: 10148659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
This paper examines the effects of a public-health intervention program on sex differentials in health and mortality during childhood. Among the different health-service packages offered as part of the experimental design, those including nutritional services seem to have been more successful in reducing excess female mortality. The reason for this success appears to have been careful follow-up of undernourished children by project workers. The results also indicate that, consistent with earlier research, girls with surviving older sisters had higher mortality rates after their first month of life. Contrary to earlier research, however, boys with surviving older brothers also have higher mortality rates, at least between the ages of one and three years. We conclude that these effects for boys and girls cannot be attributed to problems associated with larger family size, since the number of older siblings of the opposite sex (regardless of survival status) does not generally appear to be related to children's chances of survival.
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Desai DH, Amin S. Synthesis of a hapten to be used in development of immunoassays for trans-3'-hydroxycotinine, a major metabolite of cotinine. Chem Res Toxicol 1991; 4:524-7. [PMID: 1793800 DOI: 10.1021/tx00023a006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
4-Carboxyl-substituted analogues of trans-3'-hydroxycotinine were synthesized to be covalently linked to macromolecules for antibody production. 3-Pyridyl-N-methylnitrone was condensed with dimethyl fumarate to give two isomeric isoxazolidines. Hydrogenolysis of the major product [2RS-(2 alpha,3 alpha,3 beta)]-3-carbomethoxy-3- [[(benzyloxy)carbonyl]oxy]-1-methyl-5-oxo-2-(3-pyridinyl)pyrrolidine with Pd/C followed by hydrolysis gave [2RS-(2 alpha,3 beta,4 beta)]-4-hydroxy-1-methyl-5-oxo-2-(3-pyridinyl)-3- pyrrolidinecarboxylic acid. The same compound was also prepared in two steps in high yield starting with dibenzyl fumarate and 3-pyridyl-N-methylnitrone.
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Melikian AA, Prahalad KA, Amin S, Hecht SS. Comparative DNA binding of polynuclear aromatic hydrocarbons and their dihydrodiol and bay region diolepoxide metabolites in newborn mouse lung and liver. Carcinogenesis 1991; 12:1665-70. [PMID: 1893526 DOI: 10.1093/carcin/12.9.1665] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Bay region diolepoxides of polynuclear aromatic hydrocarbons (PAHs) generally are more tumorigenic than their parent PAHs in newborn mice. This contrasts to the results obtained in mouse skin, in which the same diolepoxides are frequently less tumorigenic than their parents. In order to evaluate mechanism(s) responsible for this behavior we have investigated the binding of metabolites of [3H]benzo[a]pyrene (B[a]), [3H]5- and [3H6]6-methyl-chrysene (5-MeC and 6-MeC) and their corresponding dihydrodiols and bay region diolepoxides to pulmonary and hepatic DNA in male and female newborn mice and compared the results with their tumorigenic activities. Groups of 1 day old mice were treated with 0.4 or 4 nmol of the appropriate compounds in DMSO by i.p. injection. HPLC analysis of DNA hydrolysates obtained 24 h after treatment indicated that levels of diolepoxide-DNA adducts following treatment with (+-)-[3H]7,8-dihydroxy-7,8-dihydroB[a]P and (+-)-[3H]anti-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydroB[a] P are 5- and 10-fold higher than those formed from [3H]B[a]P. The major products (70-80%) released upon enzymatic hydrolysis of DNA following treatment with [3H]B[a]P, [3H]5-MeC and [3H]6-MeC were unidentified polar compounds. Levels of these unknown products were lower and formation of diolepoxide--DNA adducts higher when test compounds were changed from parent PAHs to the corresponding dihydrodiols and diolepoxides. Comparison of these results with those of tumorigenesis studies indicates a correlation between formation of B[a]P-diolepoxide--DNA adducts and induction of tumors in newborn mouse lung, but not in liver. These observations are consistent with the high sensitivity of the newborn mouse lung towards the tumorigenic effects of bay region diolepoxides. Previous studies have demonstrated that 1R,2S-dihydroxy-3S,4R,epoxy, 1,2,3,4-tetrahydro-5-MeC (5-MeC-1R,2S-diol-3S,4R-epoxide) is a potent lung tumorigen while the corresponding diol-epoxide of 6-MeC had no effect in newborn mice. From the results of the present study, we estimate that at equimolar doses the formation of diolepoxide--DNA adducts from 5-MeC-1R,2S-diol-3S,4R-epoxide would be at least 20-fold greater than from the corresponding diolepoxide of 6-MeC in newborn mouse lung. Thus, the higher tumorigenic activity of 5-MeC-1R,2S-diol-3S,4R-epoxide compared to that of the corresponding diol epoxide of 6-MeC is partially due to its greater extent of DNA damage.
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271
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Anderson LM, Hecht SS, Kovatch RM, Amin S, Hoffmann D, Rice JM. Tumorigenicity of the tobacco-specific carcinogen 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone in infant mice. Cancer Lett 1991; 58:177-81. [PMID: 1855194 DOI: 10.1016/0304-3835(91)90097-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The tobacco-specific nitrosamine, 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK), is a potent carcinogen in adult rodents and variably effective transplacentally, depending on species. In pursuit of the thesis that human infants may be especially vulnerable targets for tumor initiation by tobacco smoke constituents, we tested the efficacy of NNK as a tumor initiator in infant mice. Cr:NIH(S) (NIH Swiss outbred) mice were given 50 mg/kg NNK i.p. on postnatal days 1, 4, 7, 10 and 14, with saline to controls. At an average age of 13-15 months, 57% of the NNK-exposed male offspring had hepatocellular tumors, with a multiplicity of 1.15 +/- 1.4, including 4 with carcinoma. Liver tumors including 2 carcinomas were found in 8 (14%) of the NNK-exposed female offspring. There were no hepatocellular neoplasms in any control. A significant increase in primary lung tumors also occurred in the NNK-treated males, with an incidence of 30/55 (57%) and a multiplicity of 0.7 +/- 0.2, vs. 7/33 (21%), multiplicity 0.3 +/- 0.6, in controls (P less than 0.025). An apparent increase in the incidence of lung tumors in NNK-treated females, 21/57 (37%) vs. 7/32 (22%) in controls, approached significance (P less than 0.1). Thus NNK was a moderately potent neonatal carcinogen for liver and lung in infant Swiss mice and more efficacious in this regard than when received transplacentally by mice of the same strain.
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272
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Amin S, Misra B, Braley J, Hecht SS. Comparative tumorigenicity in newborn mice of chrysene- and 5-alkylchrysene-1,2-diol-3,4-epoxides. Cancer Lett 1991; 58:115-8. [PMID: 2049777 DOI: 10.1016/0304-3835(91)90032-d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We determined the tumorigenicity in newborn mice of racemic anti-1,2-diol-3,4-epoxides of chrysene, 5-methylchrysene, 5-ethylchrysene and 5-propylchrysene. Among the four diol epoxides, only anti-5-methylchrysene-1,2-diol-3,4-epoxide was highly tumorigenic. It was 15-30 times more potent in induction of pulmonary tumors than the other compounds. The results demonstrate that molecular shape is critical in determining the tumorigenic activity of alkylchrysene diol epoxides. A methyl group in the same bay region as the epoxide ring leads to exceptional activity. This may be a consequence of DNA adduct conformation.
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273
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Subbarao EK, Amin S, Kumar ML. Prevaccination serologic screening for measles in health care workers. J Infect Dis 1991; 163:876-8. [PMID: 1901334 DOI: 10.1093/infdis/163.4.876] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A model was developed from which the cost-effectiveness of prevaccination serologic screening for measles could be estimated, for any combination of antibody screening costs and prevalence of antibody to measles. This model was tested using sera obtained prospectively from 222 health care workers, including 181 born in or after 1957 who had no history of measles, no measles vaccine after 1980, and no documentation of immunity to measles. In addition, 41 subjects born before 1957 who had no history of measles were studied. A rapid, reliable, and inexpensive ($5 per test) commercial ELISA was used to test for antibodies to measles; its seroprevalence in the subject population was 86%. From the model, it was estimated that prevaccination serologic testing would be cost-effective if antibody screening cost less than or equal to $12.75 per test. In this subject population, prevaccination serologic screening for measles was cost-effective.
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274
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Lewis L, Amin S, Trishman T, Civin C, Lietman P. 3′-azido-2′3′-dideoxythymidine (AZT) inhibits proliferation of normal bone marrow progenitor cells by reducing mitochondrial biogenesis. Antiviral Res 1991. [DOI: 10.1016/0166-3542(91)90285-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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275
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Barr PB, Dave DS, Amin S. Perceptual attitudes of a charitable organization: an investigative approach. Health Mark Q 1990; 8:81-95. [PMID: 10111973 DOI: 10.1300/j026v08n03_04] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
United Way of America is known nationwide for its services as a coordinator of local fund raising activities designed to meet the needs of the local community. Each United Way has many local agencies that depend upon the fund raising efforts of the organization for a significant amount of their budget. The United Way of Horry County (UWHC) operates in this manner, and over the years they have raised a significant amount of funds to support local service agencies. The UWHC is now attempting to examine possible changes by embarking upon a study designed to measure among the public the degree of awareness of United Way and the services which they provide. A sample survey was conducted and data were collected via telephone solicitation from individuals selected randomly throughout the market area of Horry County. The study identified the four most important services as: emergency assistance such as housing, fire, flood, etc., senior citizens, health care services, and drug and alcohol abuse. Furthermore, the study indicated that services which need to be added to this list include AIDS research, aid for homeless, mentally ill, and elderly.
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276
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Amin S. Infant mortality and breastmilk supplementation in Bangladesh. BANGLADESH DEVELOPMENT STUDIES 1990; 18:15-31. [PMID: 12343408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The effects of timing and type of breast-milk supplementation on infant mortality in Bangladesh are analyzed using a discrete time analog of a continuous time proportional hazards model. Data are from the Determinants of Natural Fertility Study conducted from 1975 to 1978 among some 2,000 women in Matlab thana. "The statistical analyses show that breastfeeding type at various stages of the child's life is a significant predictor of infant mortality, even when variables such as...mother's [age], education, religion and SES [socioeconomic status] are included in the model. The study shows that infants breastfed at birth have better probabilities of survival relative to those who are never breastfed or are given liquid supplements very early in life. This effect remains significant even when mother's nutrition at childbirth, which is used as a proxy for birth weight, is controlled."
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277
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Subbarao EK, Andrews-Mann L, Amin S, Greenberg J, Kumar ML. Postexposure prophylaxis for measles in a neonatal intensive care unit. J Pediatr 1990; 117:782-5. [PMID: 2231213 DOI: 10.1016/s0022-3476(05)83344-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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278
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Giguère V, Lyn S, Yip P, Siu CH, Amin S. Molecular cloning of cDNA encoding a second cellular retinoic acid-binding protein. Proc Natl Acad Sci U S A 1990; 87:6233-7. [PMID: 2166951 PMCID: PMC54507 DOI: 10.1073/pnas.87.16.6233] [Citation(s) in RCA: 164] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The vitamin A derivative retinoic acid is known to be a potent agent for control of differentiation and proliferation of epithelial cells and to exert profound effects on pattern formation during embryogenesis. Its action at the molecular level appears to be mediated by two distinct classes of proteins: a family of nuclear receptors that regulates gene transcription in a ligand-dependent fashion and a small cellular retinoic acid-binding protein (CRABP) for which a precise function remains to be elucidated. In this report, we describe the identification (by molecular cloning of its cDNA) of an isoform of CRABP, referred to as CRABP-II, expressed at high levels during mouse embryogenesis and in adult skin. We also show that CRABP-II mRNA levels are induced by at least 50-fold upon treatment of F9 teratocarcinoma cells with retinoic acid. The up-regulation of the gene encoding CRABP-II by its ligand suggests that CRABP-II might be involved in a feedback regulatory role in the mechanism of action of retinoic acid on cellular differentiation.
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279
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Amin S. The effect of women's status on sex differentials in infant and child mortality in South Asia. GENUS 1990; 46:55-69. [PMID: 12343334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
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280
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Geacintov NE, Lee MS, Ibanez V, Amin S, Hecht SS. Differences in conformations of covalent adducts derived from the binding of 5- and 6-methylchrysene diol epoxide stereoisomers to DNA. Carcinogenesis 1990; 11:985-9. [PMID: 2347073 DOI: 10.1093/carcin/11.6.985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The conformations of adducts derived from the covalent binding of four different isomeric diol epoxide derivatives of 5- or 6-methylchrysene to native double-stranded calf thymus DNA were studied by linear dichroism techniques. Out of four isomers investigated here, only the R,S,S,R enantiomer of anti-1,2-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydro-5-methylchrysene, (+)-5-MeCDE, is highly tumorigenic and mutagenic toward Salmonella typhimurium TA100; the S,R,R,S enantiomer, (-)-5-MeCDE, and the corresponding R,S,S,R and S,R,R,S enantiomers of anti-1,2,-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydro-6-methylchrysene are non-tumorigenic and much less mutagenic than (+)-5-MeCDE. [Melikian et al., (1988) Cancer Res., 48, 1781-1787] Only the DNA adducts derived from the binding of (+)-5-MeCDE are characterized by a pronounced positive linear dichroism signal at 308 nm due to the phenanthrenyl residue which is tilted at an angle of 45-48 degrees with respect to the average orientations of the axes of unoriented DNA segments. The phenanthrenyl residues derived from the covalent binding to DNA of the other three inactive or less active isomers appear to be unoriented. The defined orientation of the covalently bound phenanthrenyl residues derived from (+)-5-MeCDE corresponds to adduct conformations which are similar to those obtained from the binding of the highly tumorigenic trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene stereoisomer and other highly active bay-region diol epoxide derivatives to DNA. These findings provide further evidence that there is a correlation between DNA adduct conformation and biological activities for these series of polycyclic aromatic diol epoxide derivatives with R,S,S,R absolute configuration and which are known to bind predominantly to N2 of guanine.
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281
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Amin S, Hecht SS, Di Raddo P, Harvey RG. Comparative tumor initiating activities of cyclopentano and methyl derivatives of 5-methylchrysene and chrysene. Cancer Lett 1990; 51:17-20. [PMID: 2337893 DOI: 10.1016/0304-3835(90)90225-m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Previous studies showed that 5,6-dimethylchrysene (5,6-diMeC) and 5,7-diMec were significantly less tumorigenic than 5-methylchrysene (5-MeC). These results were unexpected based on the known mechanism of metabolic activation of 5-MeC and indicated the presence of critical steric requirements for tumorigenicity at the 6 and 7 positions of 5-MeC. In this study, the structure activity relationships were further extended by comparing the tumor-initiating activities on mouse skin of 5-MeC, 6,7-cyclopentano-5-MeC, 5,6-diMeC, 6,7-diMeC, 5,7-diMeC, chrysene and 6,7-cyclopentanochrysene. 5-MeC was the most tumorigenic compound, with activity significantly higher than all other compounds tested. Among the other compounds. Only 5,6-diMeC was significantly tumorigenic. The results demonstrate that substitution of methyl or methylene groups at the 6 or 7 positions of 5-MeC leads to a significant reduction of tumor initiating activity.
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282
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Misra B, Amin S. Synthesis and mutagenicity of trans-dihydrodiol metabolites of benzo[b]naphtho[2,1-d]thiophene. Chem Res Toxicol 1990; 3:93-7. [PMID: 1718470 DOI: 10.1021/tx00014a002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The syntheses of potentially important metabolites of benzo[b]naphtho[2,1-d]thiophene ([2,1]BNT)--trans-1,2-dihydroxy-1,2-dihydrobenzo[b]naphtho[2,1- d]thiophene ([2,1]BNT-1,2-diol) and trans-3,4-dihydroxy-3,4-dihydrobenzo[b]naphtho[2,1-d]thiophene ([2,1]BNT-3,4-diol)--are described. The syntheses involved preparation of the appropriate 1-(3-benzo[b]-thiopheneyl)-2-(methoxyphenyl)ethylenes followed by photocyclization to methoxy-[2,1]BNTs, hydrolysis to hydroxy-[2,1]BNTs, oxidation to [2,1]BNT-diones, and NaBH4 reduction. The dihydrodiols were tested for mutagenicity in Salmonella typhimurium TA 100 with activation; [2,1]BNT-3,4-diol, which can form a bay region diol epoxide, was as mutagenic as [2,1]BNT whereas [2,1]BNT-1,2-diol was inactive. These results suggest that the metabolic activation of [2,1]BNT proceeds partially via formation of a bay region diol epoxide.
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283
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Desai D, Amin S. A convenient synthesis of trans-3'-hydroxycotinine, a major nicotine metabolite found in the urine of tobacco users. Chem Res Toxicol 1990; 3:47-8. [PMID: 2131824 DOI: 10.1021/tx00013a008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
trans-3'-Hydroxycotinine is a major urinary metabolite of nicotine in smokers, but no straightforward method is available for its synthesis. A simple method was developed for preparation of trans-3'-hydroxycotinine from cotinine in two steps by using NaN[(CH3)3Si]2 and dibenzyl peroxydicarbonate, followed by base-catalyzed hydrolysis.
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284
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Lutz W, Fichtner-Schmittler H, Bülow M, Schierhorn E, Van Phat N, Sonntag E, Kosche I, Amin S, Dyer A. Occurrence and removal of hydroxide precipitates on ion-exchanged faujasite-type zeolites: zinc molecular sieves. ACTA ACUST UNITED AC 1990. [DOI: 10.1039/ft9908601899] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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285
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Amin S, Misra B, Desai D, Huie K, Hecht SS. Chromatographic conditions for separation of 32P-labeled phosphates of major polynuclear aromatic hydrocarbon--deoxyribonucleoside adducts. Carcinogenesis 1989; 10:1971-4. [PMID: 2676227 DOI: 10.1093/carcin/10.10.1971] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The 3'-monophosphates of the major deoxyribonucleoside adducts of five representative polynuclear aromatic hydrocarbons (PAH)-benzo[a]pyrene, benz[a]anthracene, chrysene, 5-methylchrysene and 6-methylchrysene--were prepared by reaction with DNA of the appropriate bay-region diol epoxides followed by enzymatic hydrolysis and HPLC purification. These standards were converted to 3',[32P]-5'-bisphosphates as in the Randerath 32P-postlabeling assay. TLC and HPLC systems for their separation are described. HPLC conditions for separation of the corresponding 3'- and 5'-monophosphates are also reported. These data will be useful for determining whether unknown DNA adducts detected by the 32P-postlabeling assay may have resulted from reactions of DNA with PAH diol epoxides.
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286
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Hecht SS, Morse MA, Amin S, Stoner GD, Jordan KG, Choi CI, Chung FL. Rapid single-dose model for lung tumor induction in A/J mice by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and the effect of diet. Carcinogenesis 1989; 10:1901-4. [PMID: 2791206 DOI: 10.1093/carcin/10.10.1901] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
This paper describes the development of a relatively rapid single-dose model for induction of lung adenomas in female A/J mice by the tobacco-specific nitrosamine 4-(methylnitros-amino)-1-(3-pyridyl)-1-butanone (NNK). Mice maintained on AIN-76A semi-synthetic diet were given a single i.p. dose of 2.5, 5 or 10 mumol NNK in saline and killed 3-7 months later. Maximum lung tumor induction, measured by lung tumors per mouse (tumor multiplicity), occurred in 3.5 months. There was no significant increase in tumor multiplicity between 3.5 and 7 months. Four months after treatment, numbers of lung tumors per mouse were 11.9 +/- 1.0 (10 mumol NNK), 3.6 +/- 0.4 (5 mumol), 0.9 +/- 0.4 (2.5 mumol) and 0.07 +/- 0.1 (saline). Lung tumor multiplicity in mice treated with a single dose of 10 mumol NNK and maintained on AIN-76A diet was significantly higher (8.3 +/- 0.5) than in mice treated with NNK and maintained on NIH-07 diet (2.5 +/- 0.3). The results of this study establish a useful bioassay for identification of compounds that can modify NNK-induced lung tumorigenesis.
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287
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Rivenson A, Djordjevic MV, Amin S, Hoffmann R. A study of tobacco carcinogenesis XLIV. Bioassay in A/J mice of some N-nitrosamines. Cancer Lett 1989; 47:111-4. [PMID: 2636026 DOI: 10.1016/0304-3835(89)90185-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The evaluation of the tumorigenic activity in A/J mouse lung of certain tobacco N-nitrosamines, namely 3-(methylnitrosamino)propionic acid (NMPA), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and 4-(methylnitrosamino)-4-(3-pyridyl)-butyric acid (iso-NNAC), had the following results (total dose in micromol per mouse/lung tumors per mouse): NMPA (200/7.1 +/- 2.9); NNK (2/15.7 +/- 4.1); iso-NNAC (200/0.24 +/- 0.43); saline control (0.2 +/- 0.4). The tumorigenic activity of NMPA was not surprising since its lower homologue, N-nitrososarcosine, as well as its higher homologue, 4-(methylnitrosamino)-butyric acid, are known carcinogens. The high tumorigenic activity of NNK in strain A/J mice confirms earlier findings as to its carcinogenic potency in rats and hamsters. The lack of tumorigenic activity of iso-NNAC supports the observation that the pyridyl rest adjacent to the nitrosamino group inhibits the activity of some tobacco-specific N-nitrosamines (TSNA). Iso-NNAC is most likely formed endogenously from the nicotine metabolites cotinine and 4-(methylamino)-4-(3-pyridyl)butyric acid.
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288
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el-Bayoumy K, Shiue GH, Amin S, Hecht SS. The effects of bay-region methyl substitution on 6-nitrochrysene mutagenicity in Salmonella typhimurium and tumorigenicity in newborn mice. Carcinogenesis 1989; 10:1685-9. [PMID: 2670305 DOI: 10.1093/carcin/10.9.1685] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The mutagenic activities in Salmonella typhimurium and tumorigenic activities in newborn mice of 6-nitrochrysene (6-NC), 5-methyl-6-nitrochrysene (5-Me-6-NC), 11-methyl-6-nitrochrysene (11-Me-6-NC) and 5-methylchrysene (5-MeC) were compared. In S. typhimurium TA100 in the absence of rat liver 9000 g supernatant, 11-Me-6-NC was the most active compound followed by 6-NC; 5-Me-6-NC and 5-MeC were inactive. In the assays conducted in the presence of rat liver 9000 g supernatant, the order of activity was 11-Me-6-NC greater than 6-NC greater than 5-Me-6-NC approximately 5-MeC. In S. typhimurium TA98 a similar trend was observed. For the tumorigenicity studies, groups of mice were treated with the appropriate compounds in DMSO by i.p. injections on the 1st, 8th and 15th day of life. At a dose of 100 nmol/mouse 6-NC induced significantly more lung tumors than 5-MeC, which in turn was more active than 11-Me-6-NC and 5-Me-6-NC. All compounds induced significant numbers of liver tumors in treated males compared to controls; the order of activity was the same as that observed for lung tumor induction. The results of this study clearly indicate that bay region methyl substitution can either inhibit (5-position) or enhance (11-position) the mutagenic activity of 6-NC. In contrast, bay region methyl substitution (5- and 11-positions) inhibited the tumorigenic activity of 6-NC in newborn mice. Since ring oxidation and nitroreduction are involved in the metabolic activation of 6-NC in newborn mice, bay region methyl substitution may either inhibit the nitroreduction pathway or hinder the formation of the appropriate bay region diol epoxide. Steric factors may be important in determining the tumorigenicity of methylated nitrochrysenes.
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289
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Anderson LM, Hecht SS, Dixon DE, Dove LF, Kovatch RM, Amin S, Hoffmann D, Rice JM. Evaluation of the transplacental tumorigenicity of the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in mice. Cancer Res 1989; 49:3770-5. [PMID: 2736518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The transplacental tumorigenicity of the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) was assessed in three strains of mice: A/J; C3H/He x C57BL/6 F1 (hereafter called C3B6F1); and Swiss outbred [Cr:NIH(S)]. NNK (100 mg/kg) was administered i.p. on Days 14, 16, and 18 of gestation to A/J and C3H/He mice and on Days 15, 17 and 19 of gestation to the Swiss mice. The effects of postnatal treatment with tumor-promoting agents, including 0.05% sodium barbital in the drinking water until death or a single dose of Aroclor 1254 (a mixture of polychlorinated biphenyls, PCB) given on Postnatal Day 8 or 56, were also examined. Progeny were sacrificed at age 24 wk (A/J) or 72 wk (C3B6F1 and Swiss). Significant incidences of tumors occurred in the lungs of strain A/J progeny and in the livers of male C3B6F1 and Swiss progeny. Lung tumor incidence was 8 of 34 (24%) in the female offspring of the A/J mice treated with NNK, compared with 1 of 39 (3%) in controls (P less than 0.05). A 2-fold difference in lung tumor incidence in male offspring of NNK-treated (4 of 23, 13%) versus control (3 of 48, 6%) A/J mice was not of statistical significance. However, the incidence of lung tumors in NNK-exposed progeny A/J mice in both sexes combined (12 of 66, 18%) was also significantly greater than in controls (4 of 87, 5%). The incidence of liver tumors in the male C3B6F1 mice exposed transplacentally to NNK was 12 of 30 (40%) compared to 8 of 46 (17%) in controls (P less than 0.05). No effects of postnatal sodium barbital or PCB were observed on transplacental NNK tumorigenicity in C3B6F1 mice. The combined incidence of liver carcinoma in male mice in all NNK-treated groups (13 of 141, 9%) was significantly greater (P less than 0.05) than in controls (5 of 144, 3%). In male Swiss mice exposed transplacentally to NNK, the incidence of liver tumors was 3 of 57 (5%) compared to 0 of 35 controls, and postnatal treatment with PCB on Day 56 caused a significant increase (5 of 26, 19%) (P less than 0.05) in the incidence of NNK-induced liver tumors. The combined incidence of liver tumors in the male offspring of the Swiss mice treated with NNK, with or without PCB, was 8 of 83 (10%) which was significantly greater (P less than 0.05) than in controls (0 of 66).(ABSTRACT TRUNCATED AT 400 WORDS)
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Weyand EH, Amin S, Huie K, Boger E, Neuber E, Hecht SS, LaVoie EJ. Effects of fluorine substitution on the DNA binding and tumorigenicity of benzo[b]fluoranthene in mouse epidermis. Chem Biol Interact 1989; 71:279-90. [PMID: 2598303 DOI: 10.1016/0009-2797(89)90041-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The effects of fluorine substitution on benzo[b]fluoranthene (B[b]F) DNA adduct formation and tumorigenicity in mouse epidermis were investigated. Fluoro derivatives studied included 1-, 6-, 7-, 8-, 9- and 11-fluoroB[b]F as well as 1,9- and 6,9-difluoroB[b]F. Each compound was applied topically to mice and hydrocarbon/DNA adduct formation was assessed using the 32P-post-labelling technique. All of the fluorinated compounds bound to DNA to a lesser extent than B[b]F. Among the fluorinated compounds, the greatest binding was observed for 8-fluoroB[b]F. Lowest levels of hydrocarbon/DNA adduct formation from the fluoro derivatives were observed for 1-, 7-, 11- and 6,9-difluoroB[b]F. The tumor-initiating activities on mouse skin of 7-, 9- and 11-fluoroB[b]F were determined. All three compounds were significantly less tumorigenic than B[b]F. The results of this study are discussed with respect to possible mechanisms of metabolic activation of B[b]F.
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Anderson JJ, Serin M, Harrop J, Amin S, Toms GL, Scott R. Natural killer cell response to respiratory syncytial virus in the Balb/c mouse model. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1989; 257:211-20. [PMID: 2482668 DOI: 10.1007/978-1-4684-5712-4_20] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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292
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Amin S, Huie K, Balanikas G, Hecht SS. Synthesis and mutagenicity of 5-alkyl-substituted chrysene-1,2-diol-3,4-epoxides. Carcinogenesis 1988; 9:2305-8. [PMID: 3191576 DOI: 10.1093/carcin/9.12.2305] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In order to explore the relationship between structure and mutagenicity of bay region diol-epoxides of chrysene substituted with an alkyl group in the bay region, we compared the mutagenicity in Salmonella typhimurium TA 100 of anti-1,2-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydrochrysene with its 5-methyl, 5-ethyl and 5-propyl derivatives. The results showed that anti-1,2-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydro-5-methylchrysene (7400 revertants/nmol) was the most mutagenic of these diol-epoxides followed by anti-1,2-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydrochrysene and its 5-ethyl derivative (1100 revertants/nmol). The 5-propyl substituted diol-epoxide was inactive at the doses tested. The results demonstrate that steric factors are dominant in the expression of methylchrysene diol-epoxide mutagenicity in S. typhimurium and suggest that the molecular shape of the 5-methyl substituted diol-epoxide leads to a unique reaction with DNA associated with high mutagenicity and tumorigenicity.
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Rivenson A, Hoffmann D, Prokopczyk B, Amin S, Hecht SS. Induction of lung and exocrine pancreas tumors in F344 rats by tobacco-specific and Areca-derived N-nitrosamines. Cancer Res 1988; 48:6912-7. [PMID: 3180100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The tobacco-specific N-nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), as well as the Areca-derived N-nitrosoguvacoline (NG) were assayed for carcinogenicity in male F344 rats by lifetime administration in the drinking water. Groups of 30 to 80 rats were treated with 0.5 ppm, 1.0 ppm, or 5.0 ppm of NNK; 5.0 ppm of NNAL, 20 ppm of NG, a mixture of 20 ppm of NG and 1 ppm of NNK, and water only in the control group. The approximate total doses of the nitrosamines (mmol/kg of body weight) in these groups were: NNK, 0.073, 0.17, and 0.68; NNAL, 0.69; NG, 4.1; NG and NNK, 4.1 and 0.17. As in previous assays in which NNK was tested by s.c. injection, the lung was its principle target organ. Lung tumor incidences in the 0.5-, 1.0-, and 5.0-ppm groups were nine of 80, 20 of 80, and 27 of 30 compared to six of 80 in the control rats. This trend was significant, P less than 0.005. Significant incidences of nasal cavity and liver tumors were observed only in the rats treated with 5.0 ppm of NNK. In contrast to the results of the s.c. bioassays of NNK, tumors of the exocrine pancreas were observed in five of 80 and nine of 80 rats treated with 0.5 and 1.0 ppm. This trend was significant, P less than 0.025. This is the first example of pancreatic tumor induction by a constituent of tobacco smoke. It is also the first finding of duct-like carcinomas in the rat pancreas, including one tumor containing epidermoid, keratin-generating tissue. NNAL, the major metabolite of NNK, induced lung tumors in 26 of 30 rats and pancreatic tumors in eight of 30 rats. It appears to be the proximate pancreatic carcinogen of NNK. NG induced pancreatic tumors in four of 30 rats, P less than 0.05. This finding requires confirmation. The mixture of NG and NNK induced lung tumors in eleven of 30 rats. There were no apparent synergistic interactions of NG and NNK. The observation of benign and malignant tumors of the lung and pancreas of rats treated with the tobacco-specific nitrosamines NNK and NNAL is discussed in respect to the causal association between cigarette smoking and cancer of the lung and pancreas.
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Amin S, Balanikas G, Huie K, Hecht SS. Synthesis and tumor-initiating activities of dimethylchrysenes. Chem Res Toxicol 1988; 1:349-55. [PMID: 2979752 DOI: 10.1021/tx00006a005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Previous studies have shown that 5-methylchrysene (5-MeC) is more carcinogenic on mouse skin than the other methylchrysenes and that the structural requirements favoring tumorigenicity of methylated polynuclear aromatic hydrocarbons are the presence of a bay region methyl group and free peri position, both adjacent to an unsubstituted angular ring. The purpose of this study was to extend these structure-activity relationships to dimethylchrysenes. The following dimethylchrysenes were synthesized: 1,5-dimethylchrysene (1,5-diMeC), 5,6-diMeC, 5,7-diMeC, 5,12-diMeC, 1,6-diMeC, 6,7-diMeC, and 6,12-diMeC. Bioassays of these compounds for tumor-initiating activity on mouse skin demonstrated that all were significantly less tumorigenic than 5-MeC; only 5,6-diMeC had significant tumorigenic activity. Since the relatively low activities of 5,7-diMeC and 5,6-diMeC were unexpected on the basis of the structural requirements stated above, anti-1,2-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydro-5,7-dimethylchrysene+ ++ (anti-5,7-diMeC-1,2-diol-3,4-epoxide) was synthesized. Its mutagenicity in Salmonella typhimurium and reactivity with calf thymus DNA were compared to those of the major ultimate carcinogen of 5-MeC, anti-5-MeC-1,2-diol-3,4-epoxide. It was strongly mutagenic (2500 revertants/nmol), although less active than anti-5-MeC-1,2-diol-3,4-epoxide (7200 revertants/nmol). Its reactivity with calf thymus DNA was similar to that of anti-5-MeC-1,2-diol-3,4-epoxide. The results of this study demonstrate that the structural requirements which favor tumorigenicity of monomethylchrysenes are not sufficient for high tumorigenicity of dimethylchrysenes.
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Hunt BJ, Yacoub M, Amin S, Devenish A, Contreras M. Induction of red blood cell destruction by graft-derived antibodies after minor ABO-mismatched heart and lung transplantation. Transplantation 1988; 46:246-9. [PMID: 3136561 DOI: 10.1097/00007890-198808000-00012] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Heart-lung transplantation (HLT) unlike other solid-organ transplants involves transplantation of a large amount of lymphoid tissue; hence there is considerable potential for graft-versus-host reaction if there is an antigen mismatch between donor and recipient. Due to the shortage of suitable donors, minor ABO-mismatched HLT (group O organs given to A, B, or AB recipients) are performed. Of 84 consecutive HLT at Harefield Hospital, nine fully ABO-matched and nine ABO-mismatched HLT were studied. Six minor ABO-mismatched HLT patients had evidence of immune destruction of recipient's red cells. Haemolysis started from days 4-12 and lasted for a mean of 13 days; in four cases transfusion support was necessary. ABO antibodies incompatible with the recipient ABO antigens, but compatible with the donor, were found in the serum and red cell eluates of these patients. In two cases, these antibodies were detected for over one year after transplantation. These changes were not seen in the fully ABO-matched controls. Our findings suggest that donor-derived lymphocytes from group O organs continue to produce anti-A and/or anti-B after transplantation, and if the recipient is group A, B, or AB, mount a secondary immune response following antigenic stimulation by the recipient's differing ABO antigens. The specific transfusion management of these patients is discussed.
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Weyand EH, Geddie N, Rice JE, Czech A, Amin S, LaVoie EJ. Metabolism and mutagenic activity of benzo[k]fluoranthene and 3-, 8- and 9-fluorobenzo[k]fluoranthene. Carcinogenesis 1988; 9:1277-81. [PMID: 3383345 DOI: 10.1093/carcin/9.7.1277] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The metabolism of 3-, 8- and 9-fluorobenzo[k]fluoranthene (B[k]F) relative to B[k]F was investigated. The major metabolites of B[k]F formed in vitro using rat liver S-9 metabolism systems were 8,9-dihydro-8,9-dihydroxyB[k]F, the 2,3-quinone of B[k]F and 3-, 8- and 9-hydroxyB[k]F. Fluorine substitution within the structure of B[k]F substantially altered the types of metabolites formed in vitro. The most pronounced effect was observed with 9-fluoroB[k]F. In contrast to B[k]F, the 8,9-dihydro-8,9-dihydroxy-, 9-hydroxy- and 10,11-dihydro-10,11-dihydroxy derivatives were not detected as metabolites of 9-fluoroB[k]F. However, either the 2,3- or 4,5-dihydrodiol of 9-fluoroB[k]F was detected. In the case of 8-fluoroB[k]F, neither the 8- nor 11-hydroxy- derivatives were detected. The principle dihydrodiols formed from 8-fluoroB[k]F were the 10,11-dihydrodiol and either the 2,3-or 4,5-dihydrodiol. The pattern of metabolites formed with 3-fluoroB[k]F was similar to that observed with B[k]F with the exception that neither the 3- nor 4-hydroxy derivatives were formed. Mass spectral data indicated that fluoro substitution is not lost to any appreciable extent during the metabolism of 3-, 8- and 9-fluoroB[k]F. The mutagenic activity of these B[k]F fluoro derivatives along with B[k]F, 2,3-dihydro-2,3-dihydroxyB[k]F, the 2,3-quinone of B[k]F and 8,9-dihydro-8,9-dihydroxyB[k]F were evaluated in Salmonella typhimurium TA100 in the presence of rat liver S-9 metabolism systems. 3-FluoroB[k]F was more mutagenic than B[k]F, while both 8- and 9-fluoroB[k]F were less active. While the 2,3-dihydrodiol and 2,3-quinone were weakly active, the 8,9-dihydrodiol had similar mutagenic potency to B[k]F.
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Melikian AA, Amin S, Huie K, Hecht SS, Harvey RG. Reactivity with DNA bases and mutagenicity toward Salmonella typhimurium of methylchrysene diol epoxide enantiomers. Cancer Res 1988; 48:1781-7. [PMID: 3258179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The reactions with DNA and mutagenic activities toward Salmonella typhimurium TA 100 of the R,S,S,R and S,R,R,S enantiomers of anti-1,2,-dihydroxy-3,4-epoxy-1,2,3,4-tetrahydro-5-methylchrysene (anti-5-MeC-1,2-diol-3,4-epoxide), anti-5-MeC-7,8-diol-9,10-epoxide, and anti-6-MeC-1,2-diol-3,4-epoxide were compared because among these compounds only the R,S,S,R enantiomer of anti-5-MeC-1,2-diol-3,4-epoxide is highly tumorigenic. The major products formed in the reaction of each racemic diol epoxide with DNA were two pairs of deoxyguanosine (dGuo) and deoxyadenosine (dAdo) adducts; one product in each pair was formed from the R,S,S,R enantiomer and the other from the S,R,R,S enantiomer of each racemic diol epoxide. Formation of products from R,S,S,R enantiomers exceeded formation of those from S,R,R,S enantiomers in each case. Among the R,S,S,R enantiomers, 5-MeC-1,2-diol-3,4-epoxide, which has a methyl group in the same bay region as the epoxide ring, was most reactive toward DNA, and in particular toward dGuo. The dGuo/dAdo adduct ratios were greater for the products formed from the R,S,S,R enantiomer compared to the S,R,R,S enantiomer of each diol epoxide. The dGuo/dAdo adduct ratios were also greater for the enantiomers of anti-5-MeC-1,2-diol-3,4-epoxide than for the enantiomers of either anti-5-MeC-7,8-diol-9,10-epoxide or anti-6-MeC-1,2-diol-3,4-epoxide. In S. typhimurium TA 100, the R,S,S,R enantiomer of anti-5-MeC-1,2-diol-3,4-epoxide was the most mutagenic compound (6700 revertants/nmol), followed by the R,S,S,R enantiomer of anti-5-MeC-7,8-diol-9,10-epoxide (1500 revertants/nmol). The other diol epoxide enantiomers were weakly active or inactive at the doses tested. The results of this study demonstrate that both the absolute configuration of a diol epoxide and the position of the methyl group have major effects on its reactivity with DNA. The greatest reactivity is seen in an R,S,S,R enantiomer with the methyl group and epoxide ring in the same bay region, e.g., the highly tumorigenic and mutagenic 5-MeC-1R,2S-diol-3S,4R-epoxide. Comparison of the dGuo/dAdo adduct ratios of the various diol epoxides with their tumorigenic and mutagenic activities suggests that dGuo adducts are important in the expression of biological activity of methylchrysene diol epoxides.
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Hunt BJ, Amin S, Yacoub M, Devenish A, Contreras M. Immune hemolysis after minor ABO-mismatched heart-lung transplants. Transplant Proc 1987; 19:4600. [PMID: 3122393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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299
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Christo GG, Shenoy S, Amin S, Marianus BV, Baliga M, Venkatesh A. A computerised neonatal data base and automated discharge summaries. Indian Pediatr 1987; 24:1105-9. [PMID: 3450662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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300
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Geddie JE, Amin S, Huie K, Hecht SS. Formation and tumorigenicity of benzo[b]fluoranthene metabolites in mouse epidermis. Carcinogenesis 1987; 8:1579-84. [PMID: 3664950 DOI: 10.1093/carcin/8.11.1579] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The metabolism in mouse epidermis of benzo[b]fluoranthene (BbF) was studied. [3H]BbF was applied topically, mice were killed at various intervals, and metabolites were extracted from the epidermis and analyzed by h.p.l.c. The major metabolites were identified by comparisons to standards as 4-, 5-, and 6-hydroxyBbF. Sulfate and glucuronide conjugates of these hydroxyBbF were also detected. Minor metabolites included 12-hydroxyBbF, BbF-1,2-diol, and BbF-11,12-diol. BbF-9,10-diol, the only known tumorigenic oxygenated derivative of BbF, was not detected. The further metabolism of BbF-9,10-diol was studied in vitro, using rat liver 9000 g supernatant. The major metabolites were identified by their spectral characteristics as 5- and 6-hydroxyBbF-9,10-diol. Little if any BbF-9,10,11,12-tetraol was detected. 5- and 6-HydroxyBbF-9,10-diol were not detected as metabolites of [3H]BbF in mouse epidermis. Several known and potential BbF metabolites--BbF-1,2-diol, BbF-11,12-diol, BbF-9,10-diol, BbF-9,10-diol-11,12-epoxide, 5- and 6-hydroxyBbF-9,10-diol, 1-hydroxyBbF, 5-hydroxyBbF, and 6-hydroxyBbF--were tested for tumor initiating activity on mouse skin. Among these, only BbF-9,10-diol showed high tumorigenic activity, but no evidence has been obtained for its formation in vivo from BbF. These studies do not support the hypothesis that BbF is metabolically activated through formation of the bay region diol epoxide, BbF-9,10-diol-11,12-epoxide.
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