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Jeengar MK, Narendra SC, Thummuri D, Magnusson M, Naidu VGM, Uppugunduri S. Local administration of 4-Thiouridine, a novel molecule with potent anti-inflammatory properties, protects against experimental colitis and arthritis. Int Immunopharmacol 2020; 85:106598. [PMID: 32442901 DOI: 10.1016/j.intimp.2020.106598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 05/07/2020] [Accepted: 05/10/2020] [Indexed: 01/10/2023]
Abstract
Previous studies in a rat model of Sephadex induced lung inflammation showed that 4-Thiouridine (4SU), a thiol substituted nucleoside, was very effective in reducing edema, leukocyte influx and TNF levels in bronchoalvelolar lavage fluid. However, little is known about the factors and mechanisms underlying these effects. In the present study, we have used two separate mouse models of chronic inflammation, a model of dextran sulphate sodium (DSS) induced colitis and a model of antigen induced arthritis, to evaluate the anti-inflammatory effect of 4-thiouridine. We have analyzed a broad spectrum of inflammatory mediators in order to delineate the mechanisms behind a potential anti-inflammatory effect of 4SU. Colitis was induced in C57BL/6 mice by administration of 3.5% DSS in drinking water for 5 days and the potential anti-colitic effect of 4SU was assessed by monitoring the disease activity index (DAI), measurement of colon length and histopathological analysis of colon tissue. We analyzed tissue myeloperoxidase (MPO) activity, serum pro-inflammatory cytokines (IL-1β, IL-6 and TNF), mRNA and protein expression of pro-inflammatory cytokines, COX-2, and NF-κB activity in colitis tissue. Intracolonic administration of 4SU (5 mg/kg & 10 mg/kg.) significantly inhibited MPO activity and reduced the levels of pro-inflammatory cytokines (IL-1β, IL-6 and TNF) as well as COX-2. Further, NF-κB activation was also blocked by attenuating the phosphorylation of IkB kinase (IKK α/β) in DSS-induced colitis tissues. Arthritis was induced by intra-articular injection of mBSA in the knee of NMRI mice pre-immunized with mBSA and 4SU was administered locally by direct injection into the knee joint. The antiarthritic potential of 4SU was calculated by histopathological scores and histochemical analysis of joint tissue. Further, immunohistochemistry was used to study inflammatory cell infiltration and expression of cytokines and adhesion molecules in the synovium. Local administration of 50-100 mg/kg 4SU at the time of arthritis onset clearly prevented development of joint inflammation and efficiently inhibited synovial expression of CD18, local cytokine production and recruitment of leukocytes to the synovium. Taken together, our data clearly demonstrates a potent anti-inflammatory effect of 4SU in two experimental models. In conclusion 4SU could be a new promising candidate for therapeutic modulation of chronic inflammatory diseases like ulcerative colitis and arthritis.
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Affiliation(s)
- Manish Kumar Jeengar
- Autoimmunity & Immune Regulation (AIR), Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden; Regional Cancer Center South East Sweden and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.
| | - Sudeep Chenna Narendra
- Autoimmunity & Immune Regulation (AIR), Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Dinesh Thummuri
- Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education & Research Institute (NIPER), Hyderabad 500037, Telangana, India
| | | | - V G M Naidu
- Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education & Research Institute (NIPER), Guwahati 781032, Assam, India
| | - Srinivas Uppugunduri
- Regional Cancer Center South East Sweden and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
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The necroptosis machinery mediates axonal degeneration in a model of Parkinson disease. Cell Death Differ 2019; 27:1169-1185. [PMID: 31591470 DOI: 10.1038/s41418-019-0408-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 07/14/2019] [Accepted: 08/06/2019] [Indexed: 11/09/2022] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative condition, characterized by motor impairment due to the progressive degeneration of dopaminergic neurons in the substantia nigra and depletion of dopamine release in the striatum. Accumulating evidence suggest that degeneration of axons is an early event in the disease, involving destruction programs that are independent of the survival of the cell soma. Necroptosis, a programmed cell death process, is emerging as a mediator of neuronal loss in models of neurodegenerative diseases. Here, we demonstrate activation of necroptosis in postmortem brain tissue from PD patients and in a toxin-based mouse model of the disease. Inhibition of key components of the necroptotic pathway resulted in a significant delay of 6-hydroxydopamine-dependent axonal degeneration of dopaminergic and cortical neurons in vitro. Genetic ablation of necroptosis mediators MLKL and RIPK3, as well as pharmacological inhibition of RIPK1 in preclinical models of PD, decreased dopaminergic neuron degeneration, improving motor performance. Together, these findings suggest that axonal degeneration in PD is mediated by the necroptosis machinery, a process here referred to as necroaxoptosis, a druggable pathway to target dopaminergic neuronal loss.
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HEIHOFF K, REDMOND RW, BRASLAVSKY SE, ROUGÉE M, SALET C, FAVRE A, BENSASSON RV. QUANTUM YIELDS OF TRIPLET AND O2(1∆g) FORMATION OF 4-THIOURIDINE IN WATER AND ACETONITRILE. Photochem Photobiol 2008. [DOI: 10.1111/php.1990.51.6.635] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Oppezzo OJ, Pizarro RA. Inhibition of sulfur incorporation to transfer RNA by ultraviolet-A radiation in Escherichia coli. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2003; 71:69-75. [PMID: 14705641 DOI: 10.1016/j.jphotobiol.2003.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
tRNA sulfurtransferase activity was assayed in Escherichia coli cell extracts obtained from bacterial suspensions exposed to a sub-lethal dose of ultraviolet-A radiation (fluence 148 kJ m(-2)) imparted at a low fluence rate (41 W m(-2)). We found that the irradiation reduced the enzymatic activity to one fourth of the control value, indicating that ultraviolet-A exposure inhibits the synthesis of 4-thiouridine, the most abundant thionucleoside in E. coli tRNA. Changes in the tRNA content of 4-thiouridine and its derived photoproduct 5-(4'-pyrimidin 2'-one) cytosine were studied in bacteria growing under ultraviolet-A irradiation. In these conditions the accumulation of photoproduct was limited, and the kinetics of this process was non-coincident with disappearance of 4-thiouridine. The results, which are compatible with the fact that ultraviolet-A induces an inhibition of the 4-thiouridine synthesis, suggest that the effect of radiation on tRNA modification is relevant to tRNA photo-inactivation in growing bacteria.
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Affiliation(s)
- Oscar J Oppezzo
- Departamento de Radiobiología, Comisión Nacional de Energía Atómica, Av. General Paz 1499, 1650 General San Martín, Buenos Aires, Argentina.
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Blazek ER, Alderfer JL, Tabaczynski WA, Stamoudis VC, Churchill ME, Peak JG, Peak MJ. A 5-4 pyrimidine-pyrimidone photoproduct produced from mixtures of thymine and 4-thiouridine irradiated with 334 nm light. Photochem Photobiol 1993; 57:255-65. [PMID: 8451287 DOI: 10.1111/j.1751-1097.1993.tb02284.x] [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: 01/30/2023]
Abstract
The nucleoside 4-thiouridine, present in some bacterial tRNA species, is known to be a chromophore and a target for near-UV light-induced growth delay and also mediates both photoprotection and near-UV cell killing in various bacterial strains. To investigate the photoreaction of 4-thiouridine with DNA or its precursors, we irradiated aqueous mixtures of thymine and 4-thiouridine with 334 nm light and then separated photoproducts using two or more stages of reversed-phase high performance liquid chromatography. The two equally abundant major photoproducts were analyzed by UV absorbance spectrophotometry, fast-atom bombardment and electron-impact mass spectrometry, and 1H- and 13C-NMR spectroscopy, and have been identified as two diastereomers of 6-hydroxy-5-[1-(beta-D-erythro-pentofuranosyl)-4'-pyrimidin-2'- one]dihydrothymine (O6hThy[5-4]Pdo), of molecular weight = 370.32. These two diastereomers, although stable at room temperature or below, are interconvertible by heating (90 degrees C for 5 min) in aqueous solution. The possible biological significance of this photoproduct is discussed, and an application as a crosslinker for oligonucleotides to selectively block replication is suggested.
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Affiliation(s)
- E R Blazek
- Department of Therapeutic Radiology, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612
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Duran N, Marcucci MC, Gatti MS, Leite LC. Different lethal effects by enzyme-generated triplet indole-3-aldehyde in different Escherichia coli strains. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1990; 4:371-8. [PMID: 2111383 DOI: 10.1016/1011-1344(90)85016-p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Strains of Escherichia coli which lack 4-thiouridine (S4U) exhibit a higher survival rate than their wild-type parents which contain S4U after treatment with enzyme-generated triplet indole-3-aldehyde. In a similar manner to results obtained with monochromatic 334 nm UV light, the survival is related to single-strand breakage of DNA in E. coli containing the pBR 322 plasmid. The effects of the excited states generated by an enzymatic system suggest that S4U is an important chromophore in the lethal effects observed. The results also suggest that the energy transferred from triplet indole-3-aldehyde to S4U may also be passed from S4U of t-RNA to DNA, possibly through a singlet oxygen intermediate generated by excited S4U, resulting in a decrease in the survival rate of E. coli containing S4U. These results emphasize the importance of excited states in biological systems.
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Affiliation(s)
- N Duran
- Instituto de Quimica, Biological Chemistry Laboratory, Universidade Estadual de Campinas, Brazil
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Abstract
Recently a number of possible functions for ergothioneine (ERT) have been suggested (1). This paper elaborates on some of these in light of overlooked or recent publications and presents additional hypotheses including: 1. Reduced ERT (ergothionol) may be an acyl carrier. 2. ERT, in conjunction with thyroid hormone and iodine, may be a cofactor in peroxidative and oxidative reactions. 3. ERT and thyroid hormone may be required for the oxidation of reduced pyridine nucleotides and the coupling of this to oxygen consumption (respiration) and ATP generation/ATPase action (heat production). 4. ERT may be required for both gene expression and repair. 5. 2-Thioimidazoles (ERT and 2-thiourocanic acid in particular) may be immunoregulatory. 6. ERT may be involved in the protection from oxidation (inactivation) of methionine and methionine containing chemoattractants, hormones, tRNA, etc. Some future research activities are suggested.
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Affiliation(s)
- M C Brummel
- Department of Pediatrics, University of Iowa, Iowa City 52242
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Kramer GF, Baker JC, Ames BN. Near-UV stress in Salmonella typhimurium: 4-thiouridine in tRNA, ppGpp, and ApppGpp as components of an adaptive response. J Bacteriol 1988; 170:2344-51. [PMID: 3283108 PMCID: PMC211128 DOI: 10.1128/jb.170.5.2344-2351.1988] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We have examined the role of 4-thiouridine in the responses of Salmonella typhimurium to near-UV irradiation. Mutants lacking 4-thiouridine (nuv) and mutants defective in the synthesis of ppGpp (guanosine 5'-diphosphate-3'-diphosphate) (relA) were found to be sensitive to killing by near-UV. Near-UV induced the synthesis of a set of proteins that were not induced in the nuv mutant. Some of these proteins were identified as oxidative defense proteins, and others were identified as ppGpp-inducible proteins. Over 100-fold increases in ApppGpp (adenosine 5', 5"'-triphosphoguanosine-3"'-diphosphate, the adenylylated form of ppGpp) were observed in wild-type cells after near-UV irradiation but not in the 4-thiouridine-deficient mutant. These data support a model in which ppGpp and ApppGpp, a dinucleotide proposed to be synthesized by tRNA-aminoacyl synthetases as a response to the cross-linking of 4-thiouridine in tRNA by near-UV, induce the synthesis of proteins necessary for resistance to near-UV irradiation.
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Affiliation(s)
- G F Kramer
- Department of Biochemistry, University of California, Berkeley 94720
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Ito A, Robb FT, Peak JG, Peak MJ. Base-specific damage induced by 4-thiouridine photosensitization with 334-nm radiation in M13 phage DNA. Photochem Photobiol 1988; 47:231-40. [PMID: 3278333 DOI: 10.1111/j.1751-1097.1988.tb02720.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Kramer GF, Ames BN. Oxidative mechanisms of toxicity of low-intensity near-UV light in Salmonella typhimurium. J Bacteriol 1987; 169:2259-66. [PMID: 3553161 PMCID: PMC212146 DOI: 10.1128/jb.169.5.2259-2266.1987] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The exposure of Salmonella typhimurium to environmentally relevant near-UV light stress has been studied by the use of a low-intensity, broad-band light source. The exposure of cells to such a light source rapidly induced a growth delay; after continuous exposure for 3 to 4 h, cells began to die at a rapid rate. The oxidative defense regulon controlled by the oxyR gene was involved in protecting cells from being killed by near-UV light. This killing may be potentiated by the overexpression of near-UV-absorbing proteins. These results are consistent with near-UV toxicity involving the absorption of light by endogenous photosensitizers, leading to the production of active oxygen species. We have shown, however, that one such species, H2O2, is not a major photoproduct involved in killing by near-UV light. Strains lacking alkyl hydroperoxide reductase were more sensitive to near-UV light, indicating that such hydroperoxides may be photoproducts. Near-UV exposure induced sensitivity to high salt levels, indicating that membranes may be a target of near-UV toxicity and a possible source of alkyl hydroperoxides. The demonstration of the inactivation of the heme-containing protein catalase indicates that direct destruction of UV-absorbing macromolecules could be another factor in near-UV toxicity. Cells which have been exposed to near-UV light for long, but sublethal, periods of time (up to 4 h) can recover and resume growth if the UV exposure is stopped but become progressively more sensitive to further stresses, such as H2O2. This result indicates that cells gradually accumulated damage during near-UV exposure until toxic levels were reached.
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Peak MJ, Johnson JS, Tuveson RW, Peak JG. Inactivation by monochromatic near-UV radiation of an Escherichia coli hemA8 mutant grown with and without delta-aminolevulinic acid: the role of DNA vs membrane damage. Photochem Photobiol 1987; 45:473-8. [PMID: 3554281 DOI: 10.1111/j.1751-1097.1987.tb05405.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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14
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Eisenstark A. Mutagenic and lethal effects of near-ultraviolet radiation (290-400 nm) on bacteria and phage. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1987; 10:317-337. [PMID: 3315655 DOI: 10.1002/em.2850100311] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Despite decades of study of the effect of near-ultraviolet radiation (NUV) on bacterial cells, insights into mechanisms of deleterious alterations and subsequent recovery are just now emerging. These insights are based on observations that 1) damage by NUV may be caused by a reactive oxygen molecule, since H2O2 may be a photoproduct of NUV; 2) some, but not all, of the effects of NUV and H2O2 are interchangeable; 3) there is an inducible regulon (oxyR) that responds to oxidative stress and is involved in protection against NUV; 4) a number of NUV-sensitive mutants are defective either in the capacity to detoxify reactive oxygen molecules or to repair DNA damage caused by NUV; and 5) recovery from NUV damage may not directly involve induction of the SOS response. Since several distinctly different photoreceptors and targets are involved, it is unknown whether NUV lethality and mutagenesis result from an accumulation of damages or whether there is a particularly critical photoeffect. To fully understand the mechanisms involved, it is important to identify the chromophore(s) of NUV, the mechanism of toxic oxygen species generation, the role of the oxidative defense regulon (oxyR), the specific lesions in the DNA, and the enzymatic events of subsequent repair.
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Affiliation(s)
- A Eisenstark
- Division of Biological Sciences, University of Missouri, Columbia 65211
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Peak JG, Peak MJ, Foote CS. Observations on the photosensitized breakage of DNA by 2-thiouracil and 334-nm ultraviolet radiation. Photochem Photobiol 1986; 44:111-6. [PMID: 3095856 DOI: 10.1111/j.1751-1097.1986.tb03573.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Cadet J, Berger M, Decarroz C, Wagner JR, van Lier JE, Ginot YM, Vigny P. Photosensitized reactions of nucleic acids. Biochimie 1986; 68:813-34. [PMID: 3092878 DOI: 10.1016/s0300-9084(86)80097-9] [Citation(s) in RCA: 156] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The main effects of near-ultraviolet and visible light on cellular DNA are reviewed with emphasis on base lesions, oligonucleotide single-strand breaks and DNA-protein cross-links. Model system photosensitization reactions of DNA are also discussed. This includes photodynamic effects, menadione-mediated photooxidation, photoionization of antibiotics, the photochemistry of 5-halogenopyrimidines and urocanic acid.
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Favre A, Chams V, Caldeira de Araujo A. Photosensitized UVA light induction of the SOS response in Escherichia coli. Biochimie 1986; 68:857-64. [PMID: 3019435 DOI: 10.1016/s0300-9084(86)80101-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Several of the factors controlling the extent of the ultraviolet light (and particularly of UVA 320 nm less than lambda less than 380 nm) induced SOS response in E. coli have been studied using a sfiA::lacZ fusion. The decreased 254 nm induced sfiA expression level triggered by a UVA-induced growth delay (Caldeira de Araujo A. & Favre A. (1986) Embo J., 5, 175-179), is closely mimicked by a transient chloramphenicol protein synthesis inhibition. In a nuvA mutant strain (lacking the growth delay effect), UVA light triggers a 30-40% lower SOS response at temperatures higher than 20 degrees C when illumination is performed under anaerobic conditions: endogenous oxygen-mediated photosensitized reactions appear to contribute to the SOS response. In contrast to the temperature independence of the sfiA induction levels obtained after 254 nm irradiation, the UVA induced response is 30-60% lower when the temperature (T) increases from a value lower than 10 degrees C to a value higher than 20 degrees C. This indicates that detoxifying enzymes play a role at T greater than 20 degrees C. Also the in vitro photooxydation of NADH to give NAD+ is described and its possible role in endogenous photosensibilizations discussed. To explain the contrasted mutagenic efficiencies of UVA light treatment when applied to cells in buffer at high fluences, and to growing cells at low fluence rates, we propose that intrinsically the UVA-induced DNA damages are able to trigger the SOS response (cyclobutyl pyrimidine dimers and some O2-dependent lesions) but also constitute premutagenic sites (some lesions leading to alkali-labile DNA breaks).(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstracts. Photochem Photobiol 1985. [DOI: 10.1111/j.1751-1097.1985.tb08912.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Peak JG, Peak MJ, Sikorski RS, Jones CA. Induction of DNA-protein crosslinks in human cells by ultraviolet and visible radiations: action spectrum. Photochem Photobiol 1985; 41:295-302. [PMID: 4011693 DOI: 10.1111/j.1751-1097.1985.tb03488.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Peak MJ, Peak JG, Moehring MP, Webb RB. Ultraviolet action spectra for DNA dimer induction, lethality, and mutagenesis in Escherichia coli with emphasis on the UVB region. Photochem Photobiol 1984; 40:613-20. [PMID: 6393154 DOI: 10.1111/j.1751-1097.1984.tb05349.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Peak M, Peak J, Foote C, Krinsky N. Oxygen-independent direct deoxyribonucleic acid backbone breakage caused by Rose Bengal and visible light. ACTA ACUST UNITED AC 1984. [DOI: 10.1016/0047-2670(84)87033-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Peak JG, Peak MJ, MacCoss M. DNA breakage caused by 334-nm ultraviolet light is enhanced by naturally occurring nucleic acid components and nucleotide coenzymes. Photochem Photobiol 1984; 39:713-6. [PMID: 6429679 DOI: 10.1111/j.1751-1097.1984.tb03914.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Peak JG, Peak MJ, Tuveson RW. Ultraviolet action spectra for aerobic and anaerobic inactivation of Escherichia coli strains specifically sensitive and resistant to near ultraviolet radiations. Photochem Photobiol 1983; 38:541-3. [PMID: 6359185 DOI: 10.1111/j.1751-1097.1983.tb03380.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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