Electrochemical sensing of tumor suppressor protein p53-deoxyribonucleic acid complex stability at an electrified interface

Czech Academy of Sciences Publication Activity Database

Paleček, Emil; Černocká, Hana; Ostatná, Veronika; Navrátilová, Lucie; Brázdová, Marie

2014-01-01

Roč. 828, MAY2014 (2014), s. 1-8 ISSN 0003-2670 R&D Projects: GA ČR(CZ) GAP301/11/2055; GA ČR(CZ) GA13-00956S; GA ČR(CZ) GA13-36108S Institutional support: RVO:68081707 Keywords : Deoxyribonucleic acid-protein binding * Tumor suppressor protein p53 * Electrochemical sensing Subject RIV: BO - Biophysics Impact factor: 4.513, year: 2014

Optoelectronic studies on heterocyclic bases of deoxyribonucleic acid for DNA photonics.

Science.gov (United States)

El-Diasty, Fouad; Abdel-Wahab, Fathy

2015-10-01

The optoelectronics study of large molecules, particularly π-stacking molecules, such as DNA is really an extremely difficult task. We perform first electronic structure calculations on the heterocyclic bases of 2'-deoxyribonucleic acid based on Lorentz-Fresnel dispersion theory. In the UV-VIS range of spectrum, many of the optoelectronic parameters for DNA four bases namely adenine, guanine, cytosine and thymine are calculated and discussed. The results demonstrate that adenine has the highest hyperpolarizability, whereas thymine has the lowest hyperpolarizability. Cytosine has the lower average oscillator energy and the higher lattice energy. Thymine infers the most stable nucleic base with the lower phonon energy. Thymine also has the highest average oscillator energy and the lower lattice energy. Moreover, the four nucleic acid bases have large band gap energies less than 5 eV with a semiconducting behavior. Guanine shows the smallest band gap and the highest Fermi level energy, whereas adenine elucidates the highest band gap energy. Copyright © 2015. Published by Elsevier B.V.

Genetic Control of the Secondary Modification of Deoxyribonucleic Acid in Escherichia coli1

Science.gov (United States)

Mamelak, Linda; Boyer, Herbert W.

1970-01-01

The wild-type restriction and modification alleles of Escherichia coli K-12 and B were found to have no measurable effect on the patterns of methylated bases in the deoxyribonucleic acid (DNA) of these strains. The genetic region controlling the methylation of cytosine in E. coli K-12 was mapped close to his, and the presence or absence of this gene in E. coli B or E. coli K had no effect on the restriction and modification properties of these strains. Thus, only a few of the methylated bases in the DNA of these strains are involved in host modification, and the biological role of the remainder remains obscure. PMID:4919756

Nucleolytic degradation of homologous and heterologous deoxyribonucleic acid molecules at the surface of competent pneumococci

International Nuclear Information System (INIS)

Seto, H.; Lopez, R.; Garrigan, O.; Tomasz, A.

1975-01-01

Competent pneumococci can catalyze the rapid and quantitative degradation of extracellular deoxyribonucleic acid (DNA) molecules through the activity of surface-located nucleases (endo- and, possibly, exonucleases as well). Both homologous and heterologous DNAs are degraded by a mechanism that seems to involve a cyclic process: (i) attachment of DNA to the cell surface followed by (ii) nucleolytic attack, and (iii) release to the medium. Processes (ii) and (iii) are both inhibited by ethylenediaminetetraacetate. Whereas surface nuclease activity is specific for competent cells, the bulk of this activity is not coupled to irreversible DNA uptake (deoxyribonuclease-resistant binding). Pneumococcal DNA treated with ultraviolet irradiation or nitrous acid (cross-linking) is selectively impaired in the ability to irreversibly bind to competent cells, whereas reversible binding is normal. (U.S.)

Interaction with Deoxyribonucleic Acid and Determination of Orientin in Lophatherum gracile Brongn by High-Performance Liquid Chromatography with Amperometric Detection

International Nuclear Information System (INIS)

Wang, Fang; Yan, Fangfang; Long, Yuling; Wang, Lili; Chen, Zilin

2015-01-01

The mechanisms of the electrochemical oxidation of orientin and its interaction with deoxyribonucleic acid have been investigated using glassy carbon electrode. The electrochemical response of orientin is due to oxidation of phenolic hydroxyl groups on orientin. The whole process is controlled by the adsorption step and concerned 4 electrons and 4 protons. Negative shift of potential and decrease of peak current for electrochemical oxidation of orientin can be observed at bare glassy carbon electrode and deoxyribonucleic acid modified electrode in 0.05 M Na_2HPO_4-KH_2PO_4 (pH 7.48), confirming the dominant electrostatic interaction between orientin and deoxyribonucleic acid. Moreover, a reliable and sensitive method of reversed-phase high-performance liquid chromatography-electrochemical detection has been developed for simultaneous determination of the isomer pair orientin/isoorientin. Chromatographic separation was carried out on a reversed-phase C_1_8 column and a mobile phase comprised of acetonitrile and acetate (0.5%, pH 2.97) by amperometric detection with a glassy carbon electrode at the working potential of +1.00 V. The method was validated for linearity, accuracy, precision, and limit of detection. Under the optimized conditions, linear regression analysis for the calibration curve showed a good linear relationship between peak area and their concentrations in the linear range of 89.2 nM to 59.5 μM for orientin with detection limit of 14.9 nM and 78.0 nM to 52.0 μM for isoorientin with a detection limit of 13.0 nM, respectively. Compared to the method using ultraviolet detection, the detection limits are greatly lowered. Finally, the proposed method has been successfully applied to the determination of orientin and isoorientin in Lophatherum gracile Brongn.

Role of deoxyribonucleic acid polymerases and deoxyribonucleic acid ligase in x-ray-induced repair synthesis in toluene-treated Escherichia coli K-12

International Nuclear Information System (INIS)

Billen, D.; Hellermann, G.R.

1976-01-01

Toluene-treated Escherichia coli mutants have been used to study the roles of deoxyribonucleic acid (DNA) polymerases I, II, and III, and of DNA ligase in repair synthesis and strand rejoining following X-irradiation. In cells possessing all three DNA polymerases, both a greater amount of repair synthesis (''exaggerated'' repair synthesis) and failure of ligation are observed when DNA ligase activity is inhibited. In a mutant lacking the polymerizing activity of DNA polymerase I, exaggerated repair synthesis is not observed, and strand rejoining does not occur even if DNA ligase is fully activated. In a mutant possessing the polymerizing activity of DNA polymerase I but lacking its 5' → 3' exonuclease activity, exaggerated repair synthesis is minimal. After irradiation, DNA polymerases II and III are capable of carrying out an adenosine 5'-triphosphate-dependent repair synthesis, but rejoining of strand breaks does not occur and exaggerated synthesis is not seen whether DNA ligase is active or not. These results suggest that DNA polymerase I and DNA ligase act together to limit repair synthesis after X irradiation and that both are necessary in toluene-treated cells for strand rejoining. DNA polymerases II and III apparently cannot complete chain elongation and gap filling, and therefore repair carried out by these enzymes does not respond to ligase action

Binding of T4 endonuclease V to deoxyribonucleic acid irradiated with ultraviolet light

International Nuclear Information System (INIS)

Seawell, P.C.; Simon, T.J.; Ganesan, A.K.

1980-01-01

Endonuclease V of bacteriophage T4 binds to uv-irradiated deoxyribonucleic acid (DNA) but not to unirradiated DNA. We have developed an assay to detect this binding, based on the retention of enzyme - DNA complexes on nitrocellulose filters. The amount of complex retained, ascertained by using radioactive DNA, is a measure of T4 endonuclease V activity. From our data we conclude that (1) T4 endonuclease V binds to uv-irradiated DNA but not to DNA that has been previously incised by the endonuclease, (2) equilibrium between the free and complexed form of the enzyme is attained under our reaction conditions, (3) dissociation of enzyme - DNA complexes is retarded by sodium cyanide, and (4) retention of enzyme - DNA complexes on nitrocellulose filters is enhanced by high concentrations of saline-citrate

Deoxyribonucleic acid repair in Escherichia coli mutants deficient in the 5'----3' exonuclease activity of deoxyribonucleic acid polymerase I and exonuclease VII

International Nuclear Information System (INIS)

Chase, J.W.; Masker, W.E.

1977-01-01

A series of Escherichia coli strains deficient in the 5'----3' exonuclease activity associated with deoxyribonucleic acid (DNA) polymerase I (exonuclease VI) and exonuclease VII has been constructed. Both of these enzymes are capable of pyrimidine dimer excision in vitro. These strains were examined for conditional lethality, sensitivity to ultraviolet (UV) and X-irradiation, postirradiation DNA degradation, and ability to excise pyrimidine dimers. It was found that strains deficient in both exonuclease VI (polAex-) and exonuclease VII (xseA-) are significantly reduced in their ability to survive incubation at elevated temperature (43 degrees C) beyond the reduction previously observed for the polAex single mutants. The UV and X-ray sensitivity of the exonuclease VI-deficient strains was not increased by the addition of the xseA7 mutation. Mutants deficient in both enzymes are about as efficient as wild-type strains at excising dimers produced by up to 40 J/m2 UV. At higher doses strains containing only polAex- mutations show reduced ability to excise dimers; however, the interpretation of dimer excision data at these doses is complicated by extreme postirradiation DNA degradation in these strains. The additional deficiency in the polAex xseA7 double-mutant strains has no significant effect on either postirradiation DNA degradation or the apparent deficiency in dimer excision at high UV doses observed in polAex single mutants

Oxygen-independent direct deoxyribonucleic acid backbone breakage caused by rose bengal and visible light

Energy Technology Data Exchange (ETDEWEB)

Peak, M J; Peak, J G; Foote, C S; Krinsky, N I

1984-01-01

An oxygen enhancement ratio of 10 for the induction of backbone single-strand breaks (SSBs) in purified deoxyribonucleic acid (DNA) by monochromatic 365 nm UV radiation was obtained. Similarly, a dose reduction factor of 10 was observed when the DNA was irradiated in the presence of 0.1 M diazabicyclo(2.2.2)octane (DABCO). To determine whether this breakage of DNA was due to the action of a reactive oxygen species such as singlet oxygen, we used the photosensitizing dye Rose Bengal and visible light as a system for generating singlet oxygen. Treatment of the DNA with Rose Bengal and 545 nm monochromatic light enhanced the rate of induction of SSBs six times, compared with the rate we obtained when the light was used alone. Elimination of oxygen or addition of 0.1 M DABCO during the 545 nm irradiation in the presence of Rose Bengal did not alter the enhancement of SSBs in the DNA caused by Rose Bengal and 545 nm radiation. The induction of SSBs in the DNA caused by irradiation of the DNA by 545 nm light in the presence of Rose Bengal was not enhanced by the use of D/sub 2/O instead of H/sub 2/O as a solvent. The results indicate that Rose Bengal plus visible light can cause biological damage without the intermediacy of reactive oxygen species, i.e. Rose Bengal and visible light can react directly with biological material, in reactions that appear to be type I photosensitized processes, independent of singlet oxygen as an intermediate.

Integrity of nuclear genomic deoxyribonucleic acid in cooked meat: Implications for food traceability.

Science.gov (United States)

Aslan, O; Hamill, R M; Sweeney, T; Reardon, W; Mullen, A M

2009-01-01

It is essential to isolate high-quality DNA from muscle tissue for PCR-based applications in traceability of animal origin. We wished to examine the impact of cooking meat to a range of core temperatures on the quality and quantity of subsequently isolated genomic (specifically, nuclear) DNA. Triplicate steak samples were cooked in a water bath (100 degrees C) until their final internal temperature was 75, 80, 85, 90, 95, or 100 degrees C, and DNA was extracted. Deoxyribonucleic acid quantity was significantly reduced in cooked meat samples compared with raw (6.5 vs. 56.6 ng/microL; P 800 bp) were observed only when using DNA from raw meat and steak cooked to lower core temperatures. Small amplicons (food authentication, it is less abundant, and results suggest that analyses should be designed to use small amplicon sizes for meat cooked to high core temperatures.

Study of the interaction of enzyme Heparanase 1 (HPSE1) active with deoxyribonucleic acids

International Nuclear Information System (INIS)

Cid, Gisele da Silva

2016-01-01

The human heparanase 1 (HPSE 1) is a protein with multiple functions and has emerged as a promising therapeutic target in the context of antitumor therapy. This fact is due to its clinical relevance in the tumor development and progression, as determined by their enzymatic ability to degrade heparan sulfate (HS), the main constituent of the extracellular matrix, providing a tumor microenvironment to tumor dissemination. In addition, this protein plays a significant role in the increase of tumor cells migration ionizing radiation dose delivery in radiotherapy from the increase in the expression levels of HPSE1. In order to evaluate in more detail the functions of active HPSE1, it has been proposed to characterize the interaction of human heparanase protein 1 with deoxyribonucleic acids. Our results are original and point to a new function of HPSE1 of the endonuclease type. (author)

Evaluation of Deoxyribonucleic Acid Toxicity Induced by the Radiopharmaceutical 99mTechnetium-Methylenediphosphonic Acid and by Stannous Chloride in Wistar Rats

Directory of Open Access Journals (Sweden)

Adriano Caldeira-de-Araujo

2012-11-01

Full Text Available Radiopharmaceuticals are employed in patient diagnostics and disease treatments. Concerning the diagnosis aspect, technetium-99m (99mTc is utilized to label radiopharmaceuticals for single photon computed emission tomography (SPECT due to its physical and chemical characteristics. 99mTc fixation on pharmaceuticals depends on a reducing agent, stannous chloride (SnCl2 being the most widely-utilized. The genotoxic, clastogenic and anegenic properties of the 99mTc-MDP(methylene diphosphonate used for bone SPECT and SnCl2 were evaluated in Wistar rat blood cells using the Comet assay and micronucleus test. The experimental approach was to endovenously administer NaCl 0.9% (negative control, cyclophosphamide 50 mg/kg b.w. (positive control, SnCl2 500 μg/mL or 99mTc-MDP to animals and blood samples taken immediately before the injection, 3, and 24 h after (in the Comet assay and 36 h after, for micronucleus test. The data showed that both SnCl2 and 99mTc-MDP-induced deoxyribonucleic acid (DNA strand breaks in rat total blood cells, suggesting genotoxic potential. The 99mTc-MDP was not able to induce a significant DNA strand breaks increase in in vivo assays. Taken together, the data presented here points to the formation of a complex between SnCl2 in the radiopharmaceutical 99mTc-MDP, responsible for the decrease in cell damage, compared to both isolated chemical agents. These findings are important for the practice of nuclear medicine.

High mobility organic field-effect transistor based on water-soluble deoxyribonucleic acid via spray coating

Energy Technology Data Exchange (ETDEWEB)

Shi, Wei; Han, Shijiao; Huang, Wei; Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

2015-01-26

High mobility organic field-effect transistors (OFETs) by inserting water-soluble deoxyribonucleic acid (DNA) buffer layer between electrodes and pentacene film through spray coating process were fabricated. Compared with the OFETs incorporated with DNA in the conventional organic solvents of ethanol and methanol: water mixture, the water-soluble DNA based OFET exhibited an over four folds enhancement of field-effect mobility from 0.035 to 0.153 cm{sup 2}/Vs. By characterizing the surface morphology and the crystalline structure of pentacene active layer through atomic force microscope and X-ray diffraction, it was found that the adoption of water solvent in DNA solution, which played a key role in enhancing the field-effect mobility, was ascribed to both the elimination of the irreversible organic solvent-induced bulk-like phase transition of pentacene film and the diminution of a majority of charge trapping at interfaces in OFETs.

No activation of new initiation points for deoxyribonucleic acid replication in BALB/c 3T3 cells transformed by Kirsten sarcoma virus

International Nuclear Information System (INIS)

Oppenheim, A.; Horowitz, A.T.

1981-01-01

BALB/c 3T3 cells were transformed by Kirsten sarcoma virus, and five clones were isolated in soft agar. Average replicon sizes of the transformed cell lines were stimated by the method of fiber-autoradiography and found to be the same size as the nontransformed 3T3 cells, analyzed in parallel. The results indicate that, unlike simian virus 40 and Epstein-Barr virus, Kirsten sarcoma virus does not activate new initiation points for cellular deoxyribonucleic acid replication in murine sarcome virus-transformed BALB/c 3T3 cells

Comparison of the Rate and Extent of Deoxyribonucleic Acid Repair and Semi-Conservative Synthesis in Bacteria Exposed to Ultra-Violet Light

Energy Technology Data Exchange (ETDEWEB)

Billen, D. [Radiation Biology Laboratory and Departments of Microbiology and Radiology, College of Medicine, University of Florida, Gainesville, FL (United States)

1968-08-15

Many bacterial strains possess the ability to repair genetic damage resulting from ultra-violet light (u.v. ) exposure. Of major importance is the occurrence of a 'repair' type of deoxyribonucleic acid (DNA) replication during 'dark repair', which presumably results in the replacement of the damaged portion of the genome. With deuterium, {sup 15}N and {sup 13}C as a density label, and buoyant density centrifugation in CsCl as a means of separating pre and post-irradiation synthesized DNA strands, the rate and extent of DNA repair synthesis in exponential - phase Escherichia coli strain B/r were determined. After u.v. exposure, {sup 3}H-thymine incorporation into the 'heavy' parental DNA strands was used to measure repair synthesis, while {sup 3}H-thymine incorporation into 'light' and newly synthesized DNA strands measured semi-conservative replication. The rate of bases incorporated by repair synthesis in the initial 15 minures of post-irradiation incubation at 37 Degree-Sign C appears to be saturated at a dose of approximately 100 ergs/mm{sup 2}. At higher doses (up to 600 ergs/mm{sup 2}) the increase observed was not proportional to dose. During this initial 15 minutes, less than 1% of the chromosomal DNA was replaced. The amount of DNA synthesized by semi-conservative replication during the initial 15 minutes was reduced with increasing u.v. dose. After exposure to 600 ergs/mm{sup 2}, repair and semiconservative DNA synthesis were nearly equivalent in the irradiated cells after 15 minutes of incubation. Repair synthesis was observed to be terminated by 45 minutes in bacteria exposed to 160 or 500 ergs/mm{sup 2} (64% and 10% survivors, respectively). The amount of genome replaced by repair synthesis at several doses was determined. Starvation for a required amino acid (resulting in an inhibition of protein and ribonucleic acid synthesis) did not prevent the repair synthesis nor grossly alter its extent. The restoration of the semi-conservative mo d e of DNA

Evaluation of deoxyribonucleic acid (DNA) isolated from human bloodstains exposed to ultraviolet light, heat, humidity, and soil contamination

International Nuclear Information System (INIS)

McNally, L.; Shaler, R.C.; Baird, M.; Balazs, I.; De Forest, P.; Kobilinsky, L.

1989-01-01

This study was designed to analyze the effects of common environmental insults on the ability to obtain deoxyribonucleic acid (DNA) restriction fragment-length polymorphisms (RFLP) patterns from laboratory prepared specimens. The environmental conditions studied include the exposure of dried bloodstains to varying amounts of relative humidity (0, 33, 67, and 98%), heat (37 degree C), and ultraviolet light for periods of up to five days. In addition, the effect of drying over a four-day period in whole blood collected with and without ethylenediaminetetraacetate (EDTA) was examined. The results of the study showed that, under the conditions studied, the integrity of DNA is not altered such that false RFLP patterns are obtained. The only effect observed was that the overall RFLP pattern becomes weaker, but individual RFLP fragments are neither created nor destroyed

Photoreactions of ruthenium(II) and osmium(II) complexes with deoxyribonucleic acid (DNA).

Science.gov (United States)

Moucheron, C; Kirsch-De Mesmaeker, A; Kelly, J M

1997-09-01

The design of Ru(II) and Os(II) complexes which are photoreactive with deoxyribonucleic acid (DNA) represents one of the main targets for the development of novel molecular tools for the study of DNA and, in the future, for the production of new, metal-based, anti-tumor drugs. In this review, we explain how it is possible to make a complex photoreactive with nucleobases and nucleic acids. According to the photophysical behaviour of the Ru(II) compounds, two types of photochemistry are expected: (1) photosubstitution of a ligand by a nucleobase and another monodentate ligand, which takes place from the triplet, metal-centred (3MC) state; this state is populated thermally from the lowest lying triplet metal to ligand charge transfer (3MLCT) state; (2) photoreaction from the 3MLCT state, corresponding to photoredox processes with DNA bases. The two photoreactivities are in competition. By modulating appropriately the redox properties of the 3MLCT state, an electron transfer process from the base to the excited complex takes place, and is directly correlated with DNA cleavage or the formation of an adduct of the complex to DNA. In this adduct, guanine is linked by N2 to the alpha-position of a non-chelating nitrogen of the polyazaaromatic ligand without destruction of the complex. Different strategies are explained which increase the affinity of the complexes for DNA and direct the complex photoreactivity to sites of special DNA topology or targeted sequences of bases. Moreover, the replacement of the Ru(II) ion by the Os(II) ion in the photoreactive complexes leads to an increased specificity of photoreaction. Indeed, only one type of photoreactivity (from the 3MLCT state) is present for the Os(II) complexes because the 3MC state is too high in energy to be populated at room temperature.

Electrogenerated chemiluminescence detection for deoxyribonucleic acid hybridization based on gold nanoparticles carrying multiple probes

International Nuclear Information System (INIS)

Wang Hui; Zhang Chengxiao; Li Yan; Qi Honglan

2006-01-01

A novel sensitive electrogenerated chemiluminescence (ECL) method for the detection deoxyribonucleic acid (DNA) hybridization based on gold nanoparticles carrying multiple probes was developed. Ruthenium bis(2,2'-bipyridine)(2,2'-bipyridine-4,4'-dicarboxylic acid)-N-hydroxysuccinimide ester (Ru(bpy) 2 (dcbpy)NHS) was used as a ECL label and gold nanoparticle as a carrier. Probe single strand DNA (ss-DNA) was self-assembled at the 3'-terminal with a thiol group to the surface of gold nanoparticle and covalently labeled at the 5'-terminal of a phosphate group with Ru(bpy) 2 (dcbpy)NHS and the resulting conjugate (Ru(bpy) 2 (dcbpy)NHS)-ss-DNA-Au, was taken as a ECL probe. When target analyte ss-DNA was immobilized on a gold electrode by self-assembled monolayer technique and then hybridized with the ECL probe to form a double-stranded DNA (ds-DNA), a strong ECL response was electrochemically generated. The ECL intensity was linearly related to the concentration of the complementary sequence (target ss-DNA) in the range from 1.0 x 10 -11 to 1.0 x 10 -8 mol L -1 , and the linear regression equation was S = 57301 + 4579.6 lg C (unit of C is mol L -1 ). A detection limit of 5.0 x 10 -12 mol L -1 for target ss-DNA was achieved. The ECL signal generated from many reporters of ECL probe prepared is greatly amplified, compared to the convention scheme which is based on one reporter per hybridization event

Initiation points for cellular deoxyribonucleic acid replication in human lymphoid cells converted by Epstein-Barr virus

International Nuclear Information System (INIS)

Oppenheim, A.; Shlomai, Z.; Ben-Bassat, H.

1981-01-01

Replicon size was estimated in two Epstein-Barr virus (EBV)-negative human lymphoma lines, BJAB and Ramos, and four EBV-positive lines derived from the former ones by infection (conversion) with two viral strains, B95-8 and P3HR-1. Logarithmic cultures were pulse-labeled with [/sup -3/H]thymidine, and the deoxyribonucleic acid was spread on microscopic slides and autoradiographed by the method of Huberman and Riggs. Three of the four EBV-converted cell lines, BJAB/B95-8, Ra/B95-8, and Ra/HRIK, were found to have significantly shorter replicons (41, 21, 54% shorter, respectively), i.e., more initiation points, than their EBV-negative parents. BJAB/HRIK had replicons which were only slightly shorter (11%) than those of BJAB. However, analysis of track length demonstrated that extensive track fusion occurred during the labeling of BJAB/HRIK, implying that its true average replicon size is shorter than the observed value. The results indicate that in analogy to simian virus 40, EBV activates new initiation points for cellular DNA replication in EBV-transformed cells

Effects of 5 Thio-D-Glucose on cellular adenosine triphosphate levels and deoxyribonucleic acid rejoining in hypoxic and aerobic Chinese hamster cells

International Nuclear Information System (INIS)

Nagle, W.A.; Moss, A.J. Jr.; Roberts, H.G. Jr.; Baker, M.L.

1980-01-01

Intracellular adenosine triphosphate (ATP) levels were measured in both hypoxic and aerobic cultures of V79 Chinese hamster cells treated with 5-thio-D-glucose (5-SH-D-Glc). This glucose analog, a known inhibitor of D-glucose transport and metabolism, reduced ATP in cell cultures allowed to become hypoxic by cell metabolism, but not in aerobic cultures treated similarly. Cells depleted of ATP were unable to rejoin x-ray induced deoxyribonucleic acid (DNA) strand breaks as measured by the alkaline sucrose gradient sedimentation technique. The inference for radiation therapy is that inhibition of glucose metabolism selectively depletes energy reserves in hypoxic cells, rendering these cells more radiosensitive and leading to a more effective tumor treatment

Uracil in formic acid hydrolysates of deoxyribonucleic acid

Science.gov (United States)

Schein, Arnold H.

1966-01-01

1. When DNA is hydrolysed with formic acid for 30min. at 175° and the hydrolysate is chromatographed on paper with propan-2-ol–2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with RF similar to that of uracil can be detected. Uracil was separated from this region and identified by its spectra in acid and alkali, and by its RF in several solvent systems. 2. Cytosine, deoxyribocytidine and deoxyribocytidylic acid similarly treated with formic acid all yielded uracil, as did a mixture of deoxyribonucleotides. 3. Approx. 4% of deoxyribonucleotide cytosine was converted into uracil by the formic acid treatment. ImagesFig. 1. PMID:5949371

Flavonoids derived from Abelmoschus esculentus attenuatesUV-B Induced cell damage in human dermal fibroblasts throughNrf2-ARE pathway

OpenAIRE

Juilee Patwardhan; Purvi Bhatt

2016-01-01

Background: Ultraviolet-B (UV-B) radiation is a smaller fraction of the total radiation reaching the Earth but leads to extensive damage to the deoxyribonucleic acid (DNA) and other biomolecules through formation of free radicals altering redox homeostasis of the cell. Abelmoschus esculentus (okra) has been known in Ayurveda as antidiabetic, hypolipidemic, demulscent, antispasmodic, diuretic, purgative, etc. Objective: The aim of this study is to evaluate the protective effect of flavonoids f...

A MapReduce approach to diminish imbalance parameters for big deoxyribonucleic acid dataset.

Science.gov (United States)

Kamal, Sarwar; Ripon, Shamim Hasnat; Dey, Nilanjan; Ashour, Amira S; Santhi, V

2016-07-01

In the age of information superhighway, big data play a significant role in information processing, extractions, retrieving and management. In computational biology, the continuous challenge is to manage the biological data. Data mining techniques are sometimes imperfect for new space and time requirements. Thus, it is critical to process massive amounts of data to retrieve knowledge. The existing software and automated tools to handle big data sets are not sufficient. As a result, an expandable mining technique that enfolds the large storage and processing capability of distributed or parallel processing platforms is essential. In this analysis, a contemporary distributed clustering methodology for imbalance data reduction using k-nearest neighbor (K-NN) classification approach has been introduced. The pivotal objective of this work is to illustrate real training data sets with reduced amount of elements or instances. These reduced amounts of data sets will ensure faster data classification and standard storage management with less sensitivity. However, general data reduction methods cannot manage very big data sets. To minimize these difficulties, a MapReduce-oriented framework is designed using various clusters of automated contents, comprising multiple algorithmic approaches. To test the proposed approach, a real DNA (deoxyribonucleic acid) dataset that consists of 90 million pairs has been used. The proposed model reduces the imbalance data sets from large-scale data sets without loss of its accuracy. The obtained results depict that MapReduce based K-NN classifier provided accurate results for big data of DNA. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Economic valuation of acidic deposition damages: Preliminary results from the 1985 NAPAP [National Acid Precipitation Assessment Program] damage assessment

International Nuclear Information System (INIS)

Callaway, J.M.; Darwin, R.F.; Nesse, R.J.

1985-01-01

This paper identifies methods used to evaluate the economic damages of acid deposition in the 1985 Damage Assessment being coordinated by the National Acid Precipitation Program. It also presents the preliminary estimates of economic damages for the Assessment. Economic damages are estimated for four effect areas: commercial agriculture and forests, recreational fishing and selected types of materials. In all but the last area, methods are used which incorporate the behavioral responses of individuals and firms or simulated physical damages to resources at risk. The preliminary nature of the estimated damages in each area is emphasized. Over all, the damage estimates should be interpreted with caution. 44 refs., 6 figs., 5 tabs

pH-responsive deoxyribonucleic acid capture/release by polydopamine functionalized magnetic nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Wang, Yu; Ma, Xiangdong; Ding, Chun; Jia, Li, E-mail: jiali@scnu.edu.cn

2015-03-03

Highlights: • PDA@Fe{sub 3}O{sub 4} were prepared and applied for efficient extraction of DNA from pathogens. • The DNA capture and release by PDA@Fe{sub 3}O{sub 4} was pH-induced. • The adsorption capacity of PDA@Fe{sub 3}O{sub 4} for DNA was 161 mg g{sup −1}. • PDA@Fe{sub 3}O{sub 4} based MSPE was combined with PCR and CE for rapid detection of pathogens. - Abstract: Polydopamine functionalized magnetic nanoparticles (PDA@Fe{sub 3}O{sub 4}) were prepared and characterized by transmission electron microscopy, scanning electron microscopy, zeta potential and vibrating sample magnetometry. They were found to enable highly efficient capture of genomic deoxyribonucleic acid (DNA). The adsorption capacity of PDA@Fe{sub 3}O{sub 4} for genomic DNA can reach 161 mg g{sup −1}. The extraction protocol used aqueous solutions for DNA binding to and releasing from the surface of the magnetic particles based on the pH inducing the charge switch of amino and phenolic hydroxyl groups on PDA@Fe{sub 3}O{sub 4}. The extracted DNA with high quality (A{sub 260}/A{sub 280} = 1.80) can be directly used as templates for polymerase chain reaction (PCR) followed by capillary electrophoresis (CE) analysis. None of the toxic chemical reagents and PCR inhibitors was used throughout the whole procedure. PDA@Fe{sub 3}O{sub 4} based magnetic solid phase extraction (MSPE) method was superior to those using commercial kit and traditional phenol–chloroform extraction methods in yield of DNA. The developed PDA@Fe{sub 3}O{sub 4} based MSPE-PCR-CE method was applied for simultaneous and fast detection of Listeria monocytogenes and Escherichia coli O157:H7 in milk.

The thyroid hormone receptor β induces DNA damage and premature senescence.

Science.gov (United States)

Zambrano, Alberto; García-Carpizo, Verónica; Gallardo, María Esther; Villamuera, Raquel; Gómez-Ferrería, Maria Ana; Pascual, Angel; Buisine, Nicolas; Sachs, Laurent M; Garesse, Rafael; Aranda, Ana

2014-01-06

There is increasing evidence that the thyroid hormone (TH) receptors (THRs) can play a role in aging, cancer and degenerative diseases. In this paper, we demonstrate that binding of TH T3 (triiodothyronine) to THRB induces senescence and deoxyribonucleic acid (DNA) damage in cultured cells and in tissues of young hyperthyroid mice. T3 induces a rapid activation of ATM (ataxia telangiectasia mutated)/PRKAA (adenosine monophosphate-activated protein kinase) signal transduction and recruitment of the NRF1 (nuclear respiratory factor 1) and THRB to the promoters of genes with a key role on mitochondrial respiration. Increased respiration leads to production of mitochondrial reactive oxygen species, which in turn causes oxidative stress and DNA double-strand breaks and triggers a DNA damage response that ultimately leads to premature senescence of susceptible cells. Our findings provide a mechanism for integrating metabolic effects of THs with the tumor suppressor activity of THRB, the effect of thyroidal status on longevity, and the occurrence of tissue damage in hyperthyroidism.

Dietary supplementation with docosahexaenoic acid (DHA) improves seminal antioxidant status and decreases sperm DNA fragmentation.

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Martínez-Soto, Juan Carlos; Domingo, Joan Carles; Cordobilla, Begoña; Nicolás, María; Fernández, Laura; Albero, Pilar; Gadea, Joaquín; Landeras, José

2016-12-01

The purpose of this study was to evaluate the effect of docosahexaenoic acid (DHA) dietary supplementation on semen quality, fatty acid composition, antioxidant capacity, and DNA fragmentation. In this randomized, double blind, placebo-controlled, parallel-group study, 74 subjects were recruited and randomly assigned to either the placebo group (n=32) or to the DHA group (n=42) to consume three 500-mg capsules of oil per day over 10 weeks. The placebo group received 1,500 mg/day of sunflower oil and the DHA group 1,500 mg/day of DHA-enriched oil. Seminal parameters (semen volume, sperm concentration, motility, morphology, and vitality), total antioxidant capacity, deoxyribonucleic acid fragmentation, and lipid composition were evaluated prior to the treatment and after 10 weeks. Finally, 57 subjects were included in the study with 25 in the placebo group and 32 in the DHA group. No differences were found in traditional sperm parameters or lipid composition of the sperm membrane after treatment. However, an increase in DHA and Omega-3 fatty acid content in seminal plasma, an improvement in antioxidant status, and a reduction in the percentage of spermatozoa with deoxyribonucleic acid damage were observed in the DHA group after 10 weeks of treatment.

Preliminary individualized chemotherapy for malignant astrocytomas based on O6-methylguanine-deoxyribonucleic acid methyltransferase methylation analysis.

Science.gov (United States)

Watanabe, Takao; Katayama, Yoichi; Ogino, Akiyoshi; Ohta, Takashi; Yoshino, Atsuo; Fukushima, Takao

2006-08-01

O(6)-methylguanine-deoxyribonucleic acid methyltransferase gene (MGMT) methylation is apparently correlated with responsiveness to nitrosourea chemotherapy, suggesting this alkylating agent should be effective against MGMT-methylated tumors. MGMT appears not to be linked to platinum resistance, so platinum chemotherapy should be used for MGMT-unmethylated tumors. This study was a preliminary trial of individualized chemotherapy based on MGMT methylation status in a total of 20 patients with newly diagnosed malignant astrocytomas (9 anaplastic astrocytomas and 11 glioblastomas multiforme). The procarbazine, 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-2(2-chloroethyl)-3-nitrosourea, and vincristine (PAV) regimen was administered to seven patients with MGMT-methylated tumors, and the carboplatin and etoposide (CE) regimen was administered to 13 patients with MGMT-unmethylated tumors. Objective response to the PAV therapy was noted in all three patients with measurable residual tumor (2 complete responses and 1 partial response). Five of the seven patients continued to be disease-free after initiation of the PAV therapy. Objective response to the CE therapy was seen in only one of seven patients with measurable residual tumor (1 partial response). Three of the 13 patients were free from progression, whereas the remaining 10 patients showed early progression. The PAV regimen is effective against MGMT-methylated malignant astrocytomas, but the CE regimen is not useful at the given dose and schedule in MGMT-unmethylated tumors.

Spectroscopic investigation on interaction and sonodynamic damage of Riboflavin to DNA under ultrasonic irradiation by using Methylene Blue as fluorescent probe

Science.gov (United States)

Wang, Qi; Wu, Qiong; Wang, Jun; Chen, Dandan; Fan, Ping; Wang, Baoxin

2014-01-01

In this paper, the Riboflavin (RF) as a sonosensitizer and Methylene Blue (MB) as a fluorescent probe were used to study the interaction and sonodynamic damage to Deoxyribonucleic Acid (DNA) by fluorescence and UV-vis spectroscopy. The results showed that the RF could efficiently bind to DNA in aqueous solution and exchange with the MB through competing reaction. And then, under ultrasonic irradiation, the RF could obviously damage the DNA. In addition, the influencing factors such as ultrasonic irradiation time and RF concentration on the sonodynamic damage to DNA were also considered. The experimental results showed that the sonodynamic damage degree increase with the increase of ultrasonic irradiation time and RF concentration. Perhaps, this paper may offer some important subjects for broadening the application of RF in sonodynamic therapy (SDT) technologies for tumor treatment.

Physical size of the donor locus and transmission of Haemophilus influenzae ampicillin resistance genes by deoxyribonucleic acid-mediated transformation

International Nuclear Information System (INIS)

Bendler, J.W. III

1976-01-01

The properties of donor deoxyribonucleic acid (DNA) from three clinical isolates and its ability to mediate the transformation of competent Rd strains to ampicillin resistance were examined. A quantitative technique for determining the resistance of individual Haemophilus influenzae cells to ampicillin was developed. When this technique was used, sensitive cells failed to tolerate levels of ampicillin greater than 0.1 to 0.2 μg/ml, whereas three resistant type b β-lactamase-producing strains could form colonies 1- to 3-μg/ml levels of the antibiotic. DNA extracted from the resistant strains elicited transformation of the auxotrophic genes in a multiply auxotrophic Rd strain. For two of the donors, transformation to ampicillin resistance occurred after the uptake of a single DNA molecule approximately 10 4 -fold less frequently than transformation of auxotrophic loci and was not observed to occur at all with the third. The frequency of transformation to ampicillin resistance was two- to fivefold higher in strain BC200 (Okinaka and Barnhart, 1974), which was cured of a defective prophage. All three clinical ampicillin-resistant strains were poor recipients, but the presence of the ampicillin resistant genes in strain BC200 did not reduce its competence

The effect of swim-up and gradient sperm preparation techniques on deoxyribonucleic acid (DNA) fragmentation in subfertile patients.

Science.gov (United States)

Oguz, Yuksel; Guler, Ismail; Erdem, Ahmet; Mutlu, Mehmet Firat; Gumuslu, Seyhan; Oktem, Mesut; Bozkurt, Nuray; Erdem, Mehmet

2018-03-23

To compare the effect of two different sperm preparation techniques, including swim-up and gradient methods on sperm deoxyribonucleic acid (DNA) fragmentation status of semen samples from unexplained and mild male factor subfertile patients undergoing intrauterine insemination (IUI). A prospective randomized study was conducted in 65 subfertile patients, including 34 unexplained and 31 male factor infertility to compare basal and post-procedure DNA fragmentation rates in swim-up and gradient techniques. Sperm DNA fragmentation rates were evaluated by a sperm chromatin dispersion (SCD) test in two portions of each sample of semen that was prepared with either swim-up or gradient techniques. Sperm motility and morphology were also assessed based on WHO 2010 criteria. Swim-up but not gradient method yielded a statistically significant reduction in the DNA fragmented sperm rate after preparation as compared to basal rates, in the semen samples of both unexplained (41.85 ± 22.04 vs. 28.58 ± 21.93, p gradient) and mild male factor (46.61 ± 19.38 vs. 30.32 ± 18.20, p gradient) subgroups. Swim-up method significantly reduces sperm DNA fragmentation rates and may have some prognostic value on intrauterine insemination in patients with decreased sperm DNA integrity.

Injury-induced inhibition of small intestinal protein and nucleic acid synthesis

International Nuclear Information System (INIS)

Carter, E.A.; Hatz, R.A.; Yarmush, M.L.; Tompkins, R.G.

1990-01-01

Small intestinal mucosal weight and nutrient absorption are significantly diminished early after cutaneous thermal injuries. Because these intestinal properties are highly dependent on rates of nucleic acid and protein synthesis, in vivo incorporation of thymidine, uridine, and leucine into small intestinal deoxyribonucleic acid, ribonucleic acid, and proteins were measured. Deoxyribonucleic acid synthesis was markedly decreased with the lowest thymidine incorporation in the jejunum (p less than 0.01); these findings were confirmed by autoradiographic identification of radiolabeled nuclei in the intestinal crypts. Protein synthesis was decreased by 6 h postinjury (p less than 0.01) but had returned to normal by 48 h. Consistent with a decreased rate of protein synthesis, ribonucleic acid synthesis was also decreased 18 h postinjury (p less than 0.01). These decreased deoxyribonucleic acid, ribonucleic acid, and protein synthesis rates are not likely a result of ischemia because in other studies of this injury model, intestinal blood flow was not significantly changed by the burn injury. Potentially, factors initiating the acute inflammatory reaction may directly inhibit nucleic acid and protein synthesis and lead to alterations in nutrient absorption and intestinal barrier function after injury

Comparison of antioxidant enzyme activities and DNA damage in chickpea (Cicer arietinum L.) genotypes exposed to vanadium.

Science.gov (United States)

Imtiaz, Muhammad; Mushtaq, Muhammad Adnan; Rizwan, Muhammad Shahid; Arif, Muhammad Saleem; Yousaf, Balal; Ashraf, Muhammad; Shuanglian, Xiong; Rizwan, Muhammad; Mehmood, Sajid; Tu, Shuxin

2016-10-01

The present study was done to elucidate the effects of vanadium (V) on photosynthetic pigments, membrane damage, antioxidant enzymes, protein, and deoxyribonucleic acid (DNA) integrity in the following chickpea genotypes: C-44 (tolerant) and Balkasar (sensitive). Changes in these parameters were strikingly dependent on levels of V, at 60 and 120 mg V L(-1) induced DNA damage in Balkasar only, while photosynthetic pigments and protein were decreased from 15 to 120 mg V L(-1) and membrane was also damaged. It was shown that photosynthetic pigments and protein production declined from 15 to 120 mg V L(-1) and the membrane was also damaged, while DNA damage was not observed at any level of V stress in C-44. Moreover, the antioxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were increased in both genotypes of chickpea against V stress; however, more activities were observed in C-44 than Balkasar. The results suggest that DNA damage in sensitive genotypes can be triggered due to exposure of higher vanadium.

Increased systemic oxidatively generated DNA and RNA damage in schizophrenia

DEFF Research Database (Denmark)

Jørgensen, Anders; Brødbæk, Kasper; Fink-Jensen, Anders

2013-01-01

such as cardiovascular disease, type 2 diabetes and dementia. We determined the urinary excretion of markers of systemic Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA) oxidation, 8-oxo-7,8-dihydro-2'-deoxyguanosine and 8-oxo-7,8-dihydroguanosine, respectively, in 40 schizophrenia patients and 40 age- and sex...

Eicosahexanoic Acid (EPA and Docosahexanoic Acid (DHA in Muscle Damage and Function

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Eisuke Ochi

2018-04-01

Full Text Available Nutritional supplementation not only helps in improving and maintaining performance in sports and exercise, but also contributes in reducing exercise fatigue and in recovery from exhaustion. Fish oil contains large amounts of omega-3 fatty acids, eicosapentaenoic acid (EPA; 20:5 n-3 and docosahexaenoic acid (DHA; 22:6 n-3. It is widely known that omega-3 fatty acids are effective for improving cardiac function, depression, cognitive function, and blood as well as lowering blood pressure. In the relationship between omega-3 fatty acids and exercise performance, previous studies have been predicted improved endurance performance, antioxidant and anti-inflammatory responses, and effectivity against delayed-onset muscle soreness. However, the optimal dose, duration, and timing remain unclear. This review focuses on the effects of omega-3 fatty acid on muscle damage and function as evaluated by human and animal studies and summarizes its effects on muscle and nerve damage, and muscle mass and strength.

Identification of Three Kinds of Citri Reticulatae Pericarpium Based on Deoxyribonucleic Acid Barcoding and High-performance Liquid Chromatography-diode Array Detection-electrospray Ionization/Mass Spectrometry/Mass Spectrometry Combined with Chemometric Analysis

Science.gov (United States)

Yu, Xiaoxue; Zhang, Yafeng; Wang, Dongmei; Jiang, Lin; Xu, Xinjun

2018-01-01

Background: Citri Reticulatae Pericarpium is the dried mature pericarp of Citrus reticulata Blanco which can be divided into “Chenpi” and “Guangchenpi.” “Guangchenpi” is the genuine Chinese medicinal material in Xinhui, Guangdong province; based on the greatest quality and least amount, it is most expensive among others. Hesperidin is used as the marker to identify Citri Reticulatae Pericarpium described in the Chinese Pharmacopoeia 2010. However, both “Chenpi” and “Guangchenpi” contain hesperidin so that it is impossible to differentiate them by measuring hesperidin. Objective: Our study aims to develop an efficient and accurate method to separate and identify “Guangchenpi” from other Citri Reticulatae Pericarpium. Materials and Methods: The genomic deoxyribonucleic acid (DNA) of all the materials was extracted and then the internal transcribed spacer 2 was amplified, sequenced, aligned, and analyzed. The secondary structures were created in terms of the database and website established by Jörg Schultz et al. High-performance liquid chromatography-diode array detection-electrospray Ionization/mass spectrometry (HPLC-DAD-ESI-MS)/MS coupled with chemometric analysis was applied to compare the differences in chemical profiles of the three kinds of Citri Reticulatae Pericarpium. Results: A total of 22 samples were classified into three groups. The results of DNA barcoding were in accordance with principal component analysis and hierarchical cluster analysis. Eight compounds were deduced from HPLC-DAD-ESI-MS/MS. Conclusions: This method is a reliable and effective tool to differentiate the three Citri Reticulatae Pericarpium. SUMMARY The internal transcribed spacer 2 regions and the secondary structure among three kinds of Citri Reticulatae Pericarpium varied considerablyAll the 22 samples were analyzed by high-performance liquid chromatography (HPLC) to obtain the chemical profilesPrincipal component analysis and hierarchical cluster analysis

Identification of a Herbal Powder by Deoxyribonucleic Acid Barcoding and Structural Analyses.

Science.gov (United States)

Sheth, Bhavisha P; Thaker, Vrinda S

2015-10-01

Authentic identification of plants is essential for exploiting their medicinal properties as well as to stop the adulteration and malpractices with the trade of the same. To identify a herbal powder obtained from a herbalist in the local vicinity of Rajkot, Gujarat, using deoxyribonucleic acid (DNA) barcoding and molecular tools. The DNA was extracted from a herbal powder and selected Cassia species, followed by the polymerase chain reaction (PCR) and sequencing of the rbcL barcode locus. Thereafter the sequences were subjected to National Center for Biotechnology Information (NCBI) basic local alignment search tool (BLAST) analysis, followed by the protein three-dimension structure determination of the rbcL protein from the herbal powder and Cassia species namely Cassia fistula, Cassia tora and Cassia javanica (sequences obtained in the present study), Cassia Roxburghii, and Cassia abbreviata (sequences retrieved from Genbank). Further, the multiple and pairwise structural alignment were carried out in order to identify the herbal powder. The nucleotide sequences obtained from the selected species of Cassia were submitted to Genbank (Accession No. JX141397, JX141405, JX141420). The NCBI BLAST analysis of the rbcL protein from the herbal powder showed an equal sequence similarity (with reference to different parameters like E value, maximum identity, total score, query coverage) to C. javanica and C. roxburghii. In order to solve the ambiguities of the BLAST result, a protein structural approach was implemented. The protein homology models obtained in the present study were submitted to the protein model database (PM0079748-PM0079753). The pairwise structural alignment of the herbal powder (as template) and C. javanica and C. roxburghii (as targets individually) revealed a close similarity of the herbal powder with C. javanica. A strategy as used here, incorporating the integrated use of DNA barcoding and protein structural analyses could be adopted, as a novel

Study of the interaction of enzyme Heparanase 1 (HPSE1) active with deoxyribonucleic acids; Estudo de interacao da enzima Heparanase 1 (HPSE 1) ativa com acido desoxirribonucleicos

Energy Technology Data Exchange (ETDEWEB)

Cid, Gisele da Silva

2016-07-01

The human heparanase 1 (HPSE 1) is a protein with multiple functions and has emerged as a promising therapeutic target in the context of antitumor therapy. This fact is due to its clinical relevance in the tumor development and progression, as determined by their enzymatic ability to degrade heparan sulfate (HS), the main constituent of the extracellular matrix, providing a tumor microenvironment to tumor dissemination. In addition, this protein plays a significant role in the increase of tumor cells migration ionizing radiation dose delivery in radiotherapy from the increase in the expression levels of HPSE1. In order to evaluate in more detail the functions of active HPSE1, it has been proposed to characterize the interaction of human heparanase protein 1 with deoxyribonucleic acids. Our results are original and point to a new function of HPSE1 of the endonuclease type. (author)

Repair of ultraviolet light-induced damage in Micrococcus radiophilus, and extremely resistant microorganism

International Nuclear Information System (INIS)

Lavin, M.F.; Jenkins, A.; Kidson, C.

1976-01-01

Repair of ultraviolet radiation damage was examined in an extremely radioresistant organism, Micrococcus radiophilus. Measurement of the number of thymine-containing dimers formed as a function of ultraviolet dose suggests that the ability of this organism to withstand high doses of ultraviolet radiation (20,000 ergs/mm 2 ) is not related to protective screening by pigments. M. radiophilus carries out a rapid excision of thymine dimers at doses of ultraviolet light up to 10,000 ergs/mm 2 . Synthesis of deoxyribonucleic acid is reduced after irradiation, but after removal of photodamage the rate approaches that in unirradiated cells. A comparison is drawn with Micrococcus luteus and M. radiodurans. We conclude that the extremely high resistance to ultraviolet irradiation in M. radiophilus is at least partly due to the presence of an efficient excision repair system

Assessment of folic acid and DNA damage in cleft lip and cleft palate

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Sivakumar Brooklyin

2014-03-01

Full Text Available Studies have identified the risk factors like folic acid deficiency during gestational period, family history for orofacial clefts, drugs like antiepileptic, vitamin A. But, the data regarding the folic acid status in children with cleft lip/palate is hardly evaluated in depth. Here, an assessment of folic acid and DNA damage were carried out in children with orofacial anomalies. Folic acid level and DNA damage were evaluated by folic acid assay (direct chemiluminescent technology and single cell gel electrophoresis or comet assay method respectively. The mean value of plasma folic acid by direct chemiluminescent technology was 6.5±3.6 nmol/L and the normal value in children ranges from 11.3 to 47.6 nmol/L. The amount of damaged DNA, measured as the tail length of the comet in cases, was 19.4±8.9 ?m and the mean percentage of DNA in tail was 16.5±3.7. Folic acid deficiency could be the reason for DNA damage.

Essential fatty acid-rich diets protect against striatal oxidative damage induced by quinolinic acid in rats.

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Morales-Martínez, Adriana; Sánchez-Mendoza, Alicia; Martínez-Lazcano, Juan Carlos; Pineda-Farías, Jorge Baruch; Montes, Sergio; El-Hafidi, Mohammed; Martínez-Gopar, Pablo Eliasib; Tristán-López, Luis; Pérez-Neri, Iván; Zamorano-Carrillo, Absalom; Castro, Nelly; Ríos, Camilo; Pérez-Severiano, Francisca

2017-09-01

Essential fatty acids have an important effect on oxidative stress-related diseases. The Huntington's disease (HD) is a hereditary neurologic disorder in which oxidative stress caused by free radicals is an important damage mechanism. The HD experimental model induced by quinolinic acid (QUIN) has been widely used to evaluate therapeutic effects of antioxidant compounds. The aim of this study was to test whether the fatty acid content in olive- or fish-oil-rich diet prevents against QUIN-related oxidative damage in rats. Rats were fed during 20 days with an olive- or a fish-oil-rich diet (15% w/w). Posterior to diet period, rats were striatally microinjected with QUIN (240 nmol/µl) or saline solution. Then, we evaluated the neurological damage, oxidative status, and gamma isoform of the peroxisome proliferator-activated receptor (PPARγ) expression. Results showed that fatty acid-rich diet, mainly by fish oil, reduced circling behavior, prevented the fall in GABA levels, increased PPARγ expression, and prevented oxidative damage in striatal tissue. In addition none of the enriched diets exerted changes neither on triglycerides or cholesterol blood levels, nor or hepatic function. This study suggests that olive- and fish-oil-rich diets exert neuroprotective effects.

~ Nigerian VeterinaryJournal ARTIClE-------------------------------------------

African Journals Online (AJOL)

causes damage to cell membrane ..... fatty acid transport by antioxidants evC. &VE) into mitochondria for energy production, ... due to generation of free radicals that could have inhibited the hypothalamic .... like protein, deoxyribonucleic acid and .... B., GELAYE, S. and AMOAH. E.A. (2002). Simulated preslaughter. 1004 ...

Radiation induced crystallinity damage in poly(L-lactic acid)

CERN Document Server

Kantoglu, O

2002-01-01

The radiation-induced crystallinity damage in poly(L-lactic acid) (PLLA) in the presence of air and in vacuum, is studied. From the heat of fusion enthalpy values of gamma irradiated samples, some changes on the thermal properties were determined. To identify these changes, first the glass transition temperature (T sub g) of L-lactic acid polymers irradiated to various doses in air and vacuum have been investigated and it is found that it is independent of irradiation atmosphere and dose. The fraction of damaged units of PLLA per unit of absorbed energy has been measured. For this purpose, SAXS and differential scanning calorimetry methods were used, and the radiation yield of number of damaged units (G(-u)) is found to be 0.74 and 0.58 for PLLA samples irradiated in vacuum and air, respectively.

In vitro antioxidant potential and deoxyribonucleic acid protecting activity of CNB-001, a novel pyrazole derivative of curcumin

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Richard L Jayaraj

2014-01-01

Full Text Available Background: Free radicals are underpinned to initiate cascade of toxic events leading to oxidative stress and resultant cell death in many neurodegenerative disorders. Now-a-days antioxidants have become mandatory in the treatment of various diseases apart from the drug′s modes of action. CNB-001, a novel hybrid molecule synthesized by combining curcumin and cyclohexyl bisphenol A is known to possess various biological activities, but the antioxidative property of the compound has not yet been elucidated. Aim: The present study is aimed to analyze various free radicals scavenging by employing in vitro antioxidant assays and to evaluate the deoxyribonucleic acid (DNA protecting the ability of CNB-001 against hydroxyl radicals. Materials and methods: The in vitro antioxidant potential of CNB-001 was evaluated by analyzing its ability to scavenge DPPH, ABTS, nitric oxide, superoxide, hydrogen peroxide, superoxide anion, hydroxyl, hydrogen peroxide radicals and reducing power using spectroscopic method. The DNA protecting activity of CNB-001 was also evaluated on pUC19 plasmid DNA subjected to hydroxyl radicals using standard agarose gel electrophoresis. Results: From the assays, it was observed that CNB-001 scavenged free radicals effectively in a dose dependent manner. CNB-001 scavenged 2,2-diphenyl-1-picrylhydrazyl (IC50 = 44.99 μg/ml, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (IC50 = 17.99 μg/ml, nitric oxide (IC50 = 1.36 μg/ml, superoxide radical (IC50 = 77.17 μg/ml, hydrogen peroxide (IC50 = 492.7 μg/ml, superoxide (IC50 = 36.92 μg/ml and hydroxyl (IC50 = 456.5 μg/ml radicals effectively and the reducing power was found to be 11.53 μg/ml. CNB-001 showed considerable protecting activity against plasmid DNA (pUC19 strand scission by ·OH at dose dependent manner. Conclusion: Results from these assays concluded that CNB-001 has a good antioxidant potential by reducing reactive oxygen and reactive nitrogen radicals and it

Antagonist effects of veratric acid against UVB-induced cell damages.

Science.gov (United States)

Shin, Seoung Woo; Jung, Eunsun; Kim, Seungbeom; Lee, Kyung-Eun; Youm, Jong-Kyung; Park, Deokhoon

2013-05-10

Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents. The simple phenolic veratric acid (VA, 3,4-dimethoxybenzoic acid) is one of the major benzoic acid derivatives from vegetables and fruits and it also occurs naturally in medicinal mushrooms which have been reported to have anti-inflammatory and anti-oxidant activities. However, it has rarely been applied in skin care. This study, therefore, aimed to explore the possible roles of veratric acid in protection against UVB-induced damage in HaCaT cells. Results showed that veratric acid can attenuate cyclobutane pyrimidine dimers (CPDs) formation, glutathione (GSH) depletion and apoptosis induced by UVB. Furthermore, veratric acid had inhibitory effects on the UVB-induced release of the inflammatory mediators such as IL-6 and prostaglandin-E2. We also confirmed the safety and clinical efficacy of veratric acid on human skin. Overall, results demonstrated significant benefits of veratric acid on the protection of keratinocyte against UVB-induced injuries and suggested its potential use in skin photoprotection.

Antagonist Effects of Veratric Acid against UVB-Induced Cell Damages

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Deokhoon Park

2013-05-01

Full Text Available Ultraviolet (UV radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents. The simple phenolic veratric acid (VA, 3,4-dimethoxybenzoic acid is one of the major benzoic acid derivatives from vegetables and fruits and it also occurs naturally in medicinal mushrooms which have been reported to have anti-inflammatory and anti-oxidant activities. However, it has rarely been applied in skin care. This study, therefore, aimed to explore the possible roles of veratric acid in protection against UVB-induced damage in HaCaT cells. Results showed that veratric acid can attenuate cyclobutane pyrimidine dimers (CPDs formation, glutathione (GSH depletion and apoptosis induced by UVB. Furthermore, veratric acid had inhibitory effects on the UVB-induced release of the inflammatory mediators such as IL-6 and prostaglandin-E2. We also confirmed the safety and clinical efficacy of veratric acid on human skin. Overall, results demonstrated significant benefits of veratric acid on the protection of keratinocyte against UVB-induced injuries and suggested its potential use in skin photoprotection.

Effects of motexafin gadolinium on DNA damage and X-ray-induced DNA damage repair, as assessed by the Comet assay

International Nuclear Information System (INIS)

Donnelly, Erling T.; Liu Yanfeng; Paul, Tracy K.; Rockwell, Sara

2005-01-01

Purpose: To investigate the effects of motexafin gadolinium (MGd) on the levels of reactive oxygen species (ROS), glutathione (GSH), and DNA damage in EMT6 mouse mammary carcinoma cells. The ability of MGd to alter radiosensitivity and to inhibit DNA damage repair after X-ray irradiation was also evaluated. Methods and Materials: Reactive oxygen species and GSH levels were assessed by 2,7-dichlorofluorescein fluorescence flow cytometry and the Tietze method, respectively. Cellular radiosensitivity was assessed by clonogenic assays. Deoxyribonucleic acid damage and DNA damage repair were assessed in plateau-phase EMT6 cells by the Comet assay and clonogenic assays. Results: Cells treated with 100 μmol/L MGd plus equimolar ascorbic acid (AA) had significantly increased levels of ROS and a 58.9% ± 3.4% decrease in GSH levels, relative to controls. Motexafin gadolinium plus AA treatment increased the hypoxic, but not the aerobic, radiosensitivity of EMT6 cells. There were increased levels of single-strand breaks in cells treated with 100 μmol/L MGd plus equimolar AA, as evidenced by changes in the alkaline tail moment (MGd + AA, 6 h: 14.7 ± 1.8; control: 2.8 ± 0.9). The level of single-strand breaks was dependent on the length of treatment. Motexafin gadolinium plus AA did not increase double-strand breaks. The repair of single-strand breaks at 2 h, but not at 4 h and 6 h, after irradiation was altered significantly in cells treated with MGd plus AA (MGd + AA, 2 h: 15.8 ± 3.4; control: 5.8 ± 0.6). Motexafin gadolinium did not alter the repair of double-strand breaks at any time after irradiation with 10 Gy. Conclusions: Motexafin gadolinium plus AA generated ROS, which in turn altered GSH homeostasis and induced DNA strand breaks. The MGd plus AA-mediated alteration of GSH levels increased the hypoxic, but not aerobic, radiosensitivity of EMT6 cells. Motexafin gadolinium altered the kinetics of single-strand break repair soon after irradiation but did not

The nature of radiolesions in deoxyribonucleic acid and their repair

International Nuclear Information System (INIS)

Moustacchi, E.

1976-01-01

The nature of different damages induced by ionizing radiations in DNA is described. The main lesions are single strand breaks, double strands breaks and base modifications. The principal enzymatic repair systems are recalled [fr

Time-resolved studies of energy transfer from meso-tetrakis(N-methylpyridinium-4-yl)- porphyrin to 3,3'-diethyl-2,2'-thiatricarbocyanine iodide along deoxyribonucleic acid Chain.

Science.gov (United States)

Kakiuchi, Toshifumi; Ito, Fuyuki; Nagamura, Toshihiko

2008-04-03

The excitation energy transfer from meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP) to 3,3'-diethyl-2,2'-thiatricarbocyanine iodide (DTTCI) along the deoxyribonucleic acid (DNA) double strand was investigated by the steady-state absorption and fluorescence measurements and time-resolved fluorescence measurements. The steady-state fluorescence spectra showed that the near-infrared fluorescence of DTTCI was strongly enhanced up to 86 times due to the energy transfer from the excited TMPyP molecule in DNA buffer solution. Furthermore, we elucidated the mechanism of fluorescence quenching and enhancement by the direct observation of energy transfer using the time-resolved measurements. The fluorescence quenching of TMPyP chiefly consists of a static component due to the formation of complex and dynamic components due to the excitation energy transfer. In a heterogeneous one-dimensional system such as a DNA chain, it was proved that the energy transfer process only carries out within the critical distance based on the Förster theory and within a threshold value estimated from the modified Stern-Volmer equation. The present results showed that DNA chain is one of the most powerful tools for nanoassemblies and will give a novel concepts of material design.

Effect of Thymine Starvation on Messenger Ribonucleic Acid Synthesis in Escherichia coli

Science.gov (United States)

Luzzati, Denise

1966-01-01

Luzzati, Denise (Institut de Biologie Physico-Chimique, Paris, France). Effect of thymine starvation on messenger ribonucleic acid synthesis in Escherichia coli. J. Bacteriol. 92:1435–1446. 1966.—During the course of thymine starvation, the rate of synthesis of messenger ribonucleic acid (mRNA, the rapidly labeled fraction of the RNA which decays in the presence of dinitrophenol or which hybridizes with deoxyribonucleic acid) decreases exponentially, in parallel with the viability of the thymine-starved bacteria. The ability of cell-free extracts of starved bacteria to incorporate ribonucleoside triphosphates into RNA was determined; it was found to be inferior to that of extracts from control cells. The analysis of the properties of cell-free extracts of starved cells shows that their decreased RNA polymerase activity is the consequence of a modification of their deoxyribonucleic acid, the ability of which to serve as a template for RNA polymerase decreases during starvation. PMID:5332402

Experimental Protoporphyria: Effect of Bile Acids on Liver Damage Induced by Griseofulvin

Directory of Open Access Journals (Sweden)

María del Carmen Martinez

2015-01-01

Full Text Available The effect of bile acids administration to an experimental mice model of Protoporphyria produced by griseofulvin (Gris was investigated. The aim was to assess whether porphyrin excretion could be accelerated by bile acids treatment in an attempt to diminish liver damage induced by Gris. Liver damage markers, heme metabolism, and oxidative stress parameters were analyzed in mice treated with Gris and deoxycholic (DXA, dehydrocholic (DHA, chenodeoxycholic, or ursodeoxycholic (URSO. The administration of Gris alone increased the activities of glutathione reductase (GRed, superoxide dismutase (SOD, alkaline phosphatase (AP, gamma glutamyl transpeptidase (GGT, and glutathione-S-transferase (GST, as well as total porphyrins, glutathione (GSH, and cytochrome P450 (CYP levels in liver. Among the bile acids studied, DXA and DHA increased PROTO IX excretion, DXA also abolished the action of Gris, reducing lipid peroxidation and hepatic GSH and CYP levels, and the activities of GGT, AP, SOD, and GST returned to control values. However, porphyrin accumulation was not prevented by URSO; instead this bile acid reduced ALA-S and the antioxidant defense enzymes system activities. In conclusion, we postulate that DXA acid would be more effective to prevent liver damage induced by Gris.

A novel enzyme-based acidizing system: Matrix acidizing and drilling fluid damage removal

Energy Technology Data Exchange (ETDEWEB)

Harris, R.E.; McKay, D.M. [Cleansorb Limited, Surrey (United Kingdom); Moses, V. [King`s College, London (United Kingdom)

1995-12-31

A novel acidizing process is used to increase the permeability of carbonate rock cores in the laboratory and to remove drilling fluid damage from cores and wafers. Field results show the benefits of the technology as applied both to injector and producer wells.

Damage and recovery of skin barrier function after glycolic acid chemical peeling and crystal microdermabrasion.

Science.gov (United States)

Song, Ji Youn; Kang, Hyun A; Kim, Mi-Yeon; Park, Young Min; Kim, Hyung Ok

2004-03-01

Superficial chemical peeling and microdermabrasion have become increasingly popular methods for producing facial rejuvenation. However, there are few studies reporting the skin barrier function changes after these procedures. To evaluate objectively the degree of damage visually and the time needed for the skin barrier function to recover after glycolic acid peeling and aluminum oxide crystal microdermabrasion using noninvasive bioengineering methods. Superficial chemical peeling using 30%, 50%, and 70% glycolic acid and aluminum oxide crystal microdermabrasion were used on the volar forearm of 13 healthy women. The skin response was measured by a visual observation and using an evaporimeter, corneometer, and colorimeter before and after peeling at set time intervals. Both glycolic acid peeling and aluminum oxide crystal microdermabrasion induced significant damage to the skin barrier function immediately after the procedure, and the degree of damage was less severe after the aluminum oxide crystal microdermabrasion compared with glycolic acid peeling. The damaged skin barrier function had recovered within 24 hours after both procedures. The degree of erythema induction was less severe after the aluminum oxide crystal microdermabrasion compared with the glycolic acid peeling procedure. The degree of erythema induced after the glycolic acid peeling procedure was not proportional to the peeling solution concentration used. The erythema subsided within 1 day after the aluminum oxide crystal microdermabrasion procedure and within 4 days after the glycolic acid peeling procedure. These results suggest that the skin barrier function is damaged after the glycolic acid peeling and aluminum oxide crystal microdermabrasion procedure but recovers within 1 to 4 days. Therefore, repeating the superficial peeling procedure at 2-week intervals will allow sufficient time for the damaged skin to recover its barrier function.

Histone dosage regulates DNA damage sensitivity in a checkpoint-independent manner by the homologous recombination pathway

Science.gov (United States)

Liang, Dun; Burkhart, Sarah Lyn; Singh, Rakesh Kumar; Kabbaj, Marie-Helene Miquel; Gunjan, Akash

2012-01-01

In eukaryotes, multiple genes encode histone proteins that package genomic deoxyribonucleic acid (DNA) and regulate its accessibility. Because of their positive charge, ‘free’ (non-chromatin associated) histones can bind non-specifically to the negatively charged DNA and affect its metabolism, including DNA repair. We have investigated the effect of altering histone dosage on DNA repair in budding yeast. An increase in histone gene dosage resulted in enhanced DNA damage sensitivity, whereas deletion of a H3–H4 gene pair resulted in reduced levels of free H3 and H4 concomitant with resistance to DNA damaging agents, even in mutants defective in the DNA damage checkpoint. Studies involving the repair of a HO endonuclease-mediated DNA double-strand break (DSB) at the MAT locus show enhanced repair efficiency by the homologous recombination (HR) pathway on a reduction in histone dosage. Cells with reduced histone dosage experience greater histone loss around a DSB, whereas the recruitment of HR factors is concomitantly enhanced. Further, free histones compete with the HR machinery for binding to DNA and associate with certain HR factors, potentially interfering with HR-mediated repair. Our findings may have important implications for DNA repair, genomic stability, carcinogenesis and aging in human cells that have dozens of histone genes. PMID:22850743

Nucleic acid-binding glycoproteins which solubilize nucleic acids in dilute acid: re-examination of the Ustilago maydis glycoproteins

Energy Technology Data Exchange (ETDEWEB)

Unrau, P.; Champ, D.R.; Young, J.L.; Grant, C.E.

1980-01-01

Holloman reported the isolation from Ustilago maydis of a glycoprotein which prevented the precipitation of nucleic acids in cold 5% trichloroacetic acid. Two glycoprotein fractions from U. maydis with this nucleic acid-solubilizing activity were isolated in our laboratory using improved purification procedures. The activity was not due to nuclease contamination. The glycoproteins are distinguished by: their ability to bind to concanavalin A-Sepharose; their differential binding to double- and single-stranded deoxyribonucleic acid, and to ribonucleic acid; their molecular weights (46,000 and 69,000); and the relative amounts present in growing versus nongrowing cells. Both fractions required sulfhydryl-reducing conditions for optimal yields, specific activity, and stability. Nucleic acid binding was cooperative, the minimum number of glycoproteins required to make a native T7 DNA molecule soluble in dilute acid being estimated at 2 and 15, respectively.

Ascorbic acid protects lipids in human plasma and low-density lipoprotein against oxidative damage

Energy Technology Data Exchange (ETDEWEB)

Frei, B. (Department of Nutrition, Harvard School of Public Health, Boston, MA (Unites States))

1991-12-01

The authors exposed human blood plasma and low-density lipoprotein (LDL) to many different oxidative challenges and followed the temporal consumption of endogenous antioxidants in relation to the initiation of oxidative damage. Under all types of oxidizing conditions, ascorbic acid completely protects lipids in plasma and LDL against detectable peroxidative damage as assessed by a specific and highly sensitive assay for lipid peroxidation. Ascorbic acid proved to be superior to the other water-soluble plasma antioxidants bilirubin, uric acid, and protein thiols as well as to the lipoprotein-associated antioxidants alpha-tocopherol, ubiquinol-10, lycopene, and beta-carotene. Although these antioxidants can lower the rate of detectable lipid peroxidation, they are not able to prevent its initiation. Only ascorbic acid is reactive enough to effectively intercept oxidants in the aqueous phase before they can attack and cause detectable oxidative damage to lipids.

Antagonist Effects of Veratric Acid against UVB-Induced Cell Damages

OpenAIRE

Deokhoon Park; Jong-Kyung Youm; Kyung-Eun Lee; Seungbeom Kim; Eunsun Jung; Seoung Woo Shin

2013-01-01

Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents. The simple phenolic veratric acid (VA, ...

Quinacrine enhances carmustine therapy of experimental rat glioma.

Science.gov (United States)

Reyes, S; Herrera, L A; Ostrosky, P; Sotelo, J

2001-10-01

The high rate of mutagenesis in malignant cells has been considered to be a primary factor in the appearance of chemotherapy-resistant cell clones in glioblastomas. Quinacrine binds strongly to deoxyribonucleic acid, preventing mutagenesis. We investigated whether quinacrine could improve carmustine therapy in C6 cell cultures and in C6 malignant gliomas implanted subcutaneously into Wistar rats. A potential chemopreventive effect of quinacrine on acquired resistance to carmustine therapy was studied in vitro and in vivo. Deoxyribonucleic acid damage was measured in cultured C6 cells by using the micronucleus test. Wistar rats with subcutaneously implanted C6 gliomas were treated with carmustine, quinacrine, or carmustine plus quinacrine, using pharmacological schemes similar to those used for human patients. The addition of quinacrine to cultured C6 cells did not modify carmustine-induced cytotoxicity; however, the deoxyribonucleic acid damage in surviving cells was minor, as indicated by the frequency of micronucleated cells. The surviving cells continued to be susceptible to a second exposure to carmustine, in contrast to non-quinacrine-treated control cells, which developed resistance to carmustine in a subsequent exposure (P < 0.05). The rate of tumor remission was higher for glioma-bearing rats treated with quinacrine plus carmustine, compared with rats treated with carmustine alone (P < 0.01). The addition of quinacrine to carmustine therapy increases the antineoplastic effect of the carmustine therapy. Our results suggest that chemical inhibition of mutagenesis in malignant glial cells during chemotherapy prevents the appearance of resistant clones.

Serum uric acid levels contribute to new renal damage in systemic lupus erythematosus patients.

Science.gov (United States)

Reátegui-Sokolova, C; Ugarte-Gil, Manuel F; Gamboa-Cárdenas, Rocío V; Zevallos, Francisco; Cucho-Venegas, Jorge M; Alfaro-Lozano, José L; Medina, Mariela; Rodriguez-Bellido, Zoila; Pastor-Asurza, Cesar A; Alarcón, Graciela S; Perich-Campos, Risto A

2017-04-01

This study aims to determine whether uric acid levels contribute to new renal damage in systemic lupus erythematosus (SLE) patients. This prospective study was conducted in consecutive patients seen since 2012. Patients had a baseline visit and follow-up visits every 6 months. Patients with ≥2 visits were included; those with end-stage renal disease (regardless of dialysis or transplantation) were excluded. Renal damage was ascertained using the SLICC/ACR damage index (SDI). Univariable and multivariable Cox-regression models were performed to determine the risk of new renal damage. Uric acid was included as a continuous and dichotomous (per receiving operating characteristic curve) variable. Multivariable models were adjusted for age at diagnosis, disease duration, socioeconomic status, SLEDAI, SDI, serum creatinine, baseline use of prednisone, antimalarials, and immunosuppressive drugs. One hundred and eighty-six patients were evaluated; their mean (SD) age at diagnosis was 36.8 (13.7) years; nearly all patients were mestizo. Disease duration was 7.7 (6.8) years. Follow-up time was 2.3 (1.1) years. The SLEDAI was 5.2 (4.3) and the SDI 0.8 (1.1). Uric acid levels were 4.5 (1.3) mg/dl. During follow-up, 16 (8.6%) patients developed at least one new point in the renal domain of the SDI. In multivariable analyses, uric acid levels (continuous and dichotomous) at baseline predicted the development of new renal damage (HR 3.21 (1.39-7.42), p 0.006; HR 18.28 (2.80-119.48), p 0.002; respectively). Higher uric acid levels contribute to the development of new renal damage in SLE patients independent of other well-known risk factors for such occurrence.

Flavonoids Derived from Abelmoschus esculentus Attenuates UV-B Induced Cell Damage in Human Dermal Fibroblasts Through Nrf2-ARE Pathway.

Science.gov (United States)

Patwardhan, Juilee; Bhatt, Purvi

2016-05-01

Ultraviolet-B (UV-B) radiation is a smaller fraction of the total radiation reaching the Earth but leads to extensive damage to the deoxyribonucleic acid (DNA) and other biomolecules through formation of free radicals altering redox homeostasis of the cell. Abelmoschus esculentus (okra) has been known in Ayurveda as antidiabetic, hypolipidemic, demulscent, antispasmodic, diuretic, purgative, etc. The aim of this study is to evaluate the protective effect of flavonoids from A. esculentus against UV-B-induced cell damage in human dermal fibroblasts. UV-B protective activity of ethyl acetate (EA) fraction of okra was studied against UV-B-induced cytotoxicity, antioxidant regulation, oxidative DNA damage, intracellular reactive oxygen species (ROS) generation, apoptotic morphological changes, and regulation of heme oxygenase-1 (HO-1) gene through nuclear factor E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway. Flavonoid-rich EA fraction depicted a significant antioxidant potential also showing presence of rutin. Pretreatment of cells with EA fraction (10-30 μg/ml) prevented UV-B-induced cytotoxicity, depletion of endogenous enzymatic antioxidants, oxidative DNA damage, intracellular ROS production, apoptotic changes, and overexpression of Nrf2 and HO-1. Our study demonstrated for the 1(st) time that EA fraction of okra may reduce oxidative stress through Nrf2-ARE pathway as well as through endogenous enzymatic antioxidant system. These results suggested that flavonoids from okra may be considered as potential UV-B protective agents and may also be formulated into herbal sunscreen for topical application. Flavonoid-enriched ethyl acetate (EA) fraction from A. esculentus protected against ultraviolet-B (UV-B)-induced oxidative DNA damageEA fraction prevented UV-B-induced cytotoxicity, depletion of endogenous enzymatic antioxidants, and intracellular reactive oxygen species productionEA fraction could reduce oxidative stress through the Nrf2-ARE

Terbium fluorescence as a sensitive, inexpensive probe for UV-induced damage in nucleic acids

International Nuclear Information System (INIS)

El-Yazbi, Amira F.; Loppnow, Glen R.

2013-01-01

Graphical abstract: -- Highlights: •Simple, inexpensive, mix-and-read assay for positive detection of DNA damage. •Recognition of undamaged DNA via hybridization to a hairpin probe. •Terbium(III) fluorescence reports the amount of damage by binding to ssDNA. •Tb/hairpin is a highly selective and sensitive fluorescent probe for DNA damage. -- Abstract: Much effort has been focused on developing methods for detecting damaged nucleic acids. However, almost all of the proposed methods consist of multi-step procedures, are limited, require expensive instruments, or suffer from a high level of interferences. In this paper, we present a novel simple, inexpensive, mix-and-read assay that is generally applicable to nucleic acid damage and uses the enhanced luminescence due to energy transfer from nucleic acids to terbium(III) (Tb 3+ ). Single-stranded oligonucleotides greatly enhance the Tb 3+ emission, but duplex DNA does not. With the use of a DNA hairpin probe complementary to the oligonucleotide of interest, the Tb 3+ /hairpin probe is applied to detect ultraviolet (UV)-induced DNA damage. The hairpin probe hybridizes only with the undamaged DNA. However, the damaged DNA remains single-stranded and enhances the intrinsic fluorescence of Tb 3+ , producing a detectable signal directly proportional to the amount of DNA damage. This allows the Tb 3+ /hairpin probe to be used for sensitive quantification of UV-induced DNA damage. The Tb 3+ /hairpin probe showed superior selectivity to DNA damage compared to conventional molecular beacons probes (MBs) and its sensitivity is more than 2.5 times higher than MBs with a limit of detection of 4.36 ± 1.2 nM. In addition, this probe is easier to synthesize and more than eight times cheaper than MBs, which makes its use recommended for high-throughput, quantitative analysis of DNA damage

Comet assay optimization for assessment of DNA damage due to radiation exposure

International Nuclear Information System (INIS)

Dwi Ramadhani; Devita Tetriana; Viria Agesti Suvifan

2016-01-01

Comet assay can be used to measure the deoxyribonucleic acid (DNA) damage level caused by ionizing radiation exposure in peripheral blood lymphocytes. The principle of the comet assay is based on the amount of denatured DNA fragments that migrated out of the cell nucleus during electrophoresis. There are several aspects that must be concerned when doing the comet assay. For example the agarose concentration, duration of alkaline incubation, electrophoresis conditions (time, temperature, and voltage gradient), and the measurement parameters that used in analyze the comet. Percentage of DNA in the comet tail (% tail DNA) is strongly recommended as a parameter when analyze the comet because it can be converted to lesions per 106 base pairs (bp) using calibration curve that show relationship between the dose of ionizing radiation and % tail DNA. To obtain an accurate result, the calibration curve must be made and comet should be analyzing using image processing analysis software since it can be increase the precision and reduce the subjectivity of the measurement process. (author)

In Barrett's esophagus patients and Barrett's cell lines, ursodeoxycholic acid increases antioxidant expression and prevents DNA damage by bile acids.

Science.gov (United States)

Peng, Sui; Huo, Xiaofang; Rezaei, Davood; Zhang, Qiuyang; Zhang, Xi; Yu, Chunhua; Asanuma, Kiyotaka; Cheng, Edaire; Pham, Thai H; Wang, David H; Chen, Minhu; Souza, Rhonda F; Spechler, Stuart Jon

2014-07-15

Hydrophobic bile acids like deoxycholic acid (DCA), which cause oxidative DNA damage and activate NF-κB in Barrett's metaplasia, might contribute to carcinogenesis in Barrett's esophagus. We have explored mechanisms whereby ursodeoxycholic acid (UDCA, a hydrophilic bile acid) protects against DCA-induced injury in vivo in patients and in vitro using nonneoplastic, telomerase-immortalized Barrett's cell lines. We took biopsies of Barrett's esophagus from 21 patients before and after esophageal perfusion with DCA (250 μM) at baseline and after 8 wk of oral UDCA treatment. DNA damage was assessed by phospho-H2AX expression, neutral CometAssay, and phospho-H2AX nuclear foci formation. Quantitative PCR was performed for antioxidants including catalase and GPX1. Nrf2, catalase, and GPX1 were knocked down with siRNAs. Reporter assays were performed using a plasmid construct containing antioxidant responsive element. In patients, baseline esophageal perfusion with DCA significantly increased phospho-H2AX and phospho-p65 in Barrett's metaplasia. Oral UDCA increased GPX1 and catalase levels in Barrett's metaplasia and prevented DCA perfusion from inducing DNA damage and NF-κB activation. In cells, DCA-induced DNA damage and NF-κB activation was prevented by 24-h pretreatment with UDCA, but not by mixing UDCA with DCA. UDCA activated Nrf2 signaling to increase GPX1 and catalase expression, and protective effects of UDCA pretreatment were blocked by siRNA knockdown of these antioxidants. UDCA increases expression of antioxidants that prevent toxic bile acids from causing DNA damage and NF-κB activation in Barrett's metaplasia. Elucidation of this molecular pathway for UDCA protection provides rationale for clinical trials on UDCA for chemoprevention in Barrett's esophagus. Copyright © 2014 the American Physiological Society.

Bioactivation of carboxylic acid compounds by UDP-Glucuronosyltransferases to DNA-damaging intermediates: role of glycoxidation and oxidative stress in genotoxicity.

Science.gov (United States)

Sallustio, Benedetta C; Degraaf, Yvette C; Weekley, Josephine S; Burcham, Philip C

2006-05-01

Nonenzymatic modification of proteins by acyl glucuronides is well documented; however, little is known about their potential to damage DNA. We have previously reported that clofibric acid undergoes glucuronidation-dependent bioactivation to DNA-damaging species in cultured mouse hepatocytes. The aim of this study was to investigate the mechanisms underlying such DNA damage, and to screen chemically diverse carboxylic acid drugs for their DNA-damaging potential in glucuronidation proficient murine hepatocytes. Cells were incubated with each aglycone for 18 h, followed by assessment of compound cytotoxicity using the MTT assay and evaluation of DNA damage using the Comet assay. Relative cytotoxic potencies were ketoprofen > diclofenac, benoxaprofen, nafenopin > gemfibrozil, probenecid > bezafibrate > clofibric acid. At a noncytotoxic (0.1 mM) concentration, only benoxaprofen, nafenopin, clofibric acid, and probenecid significantly increased Comet moments (P Clofibric acid and probenecid exhibited the greatest DNA-damaging potency, producing significant DNA damage at 0.01 mM concentrations. The two drugs produced maximal increases in Comet moment of 4.51 x and 2.57 x control, respectively. The glucuronidation inhibitor borneol (1 mM) abolished the induction of DNA damage by 0.5 mM concentrations of clofibric acid and probenecid. In an in vitro cell-free system, clofibric acid glucuronide was 10 x more potent than glucuronic acid in causing DNA strand-nicking, although both compounds showed similar rates of autoxidation to generate hydroxyl radicals. In cultured hepatocytes, the glycation inhibitor, aminoguanidine, and the iron chelator, desferrioxamine mesylate, inhibited DNA damage by clofibric acid, whereas the free radical scavengers Trolox and butylated hydroxytoluene, and the superoxide dismutase mimetic bis-3,5-diisopropylsalicylate had no effect. In conclusion, clinically relevant concentrations of two structurally unrelated carboxylic acids, probenecid and

Four Proteins Synthesized in Response to Deoxyribonucleic Acid Damage in Micrococcus Radiodurans

DEFF Research Database (Denmark)

Hansen, M. T.

1980-01-01

Four proteins, alpha beta, gamma, and delta, preferentially synthesized in ultraviolet light-treated cells of Micrococcus radiodurans, were characterized in terms of their molecular weights and isoelectric points. Within the sublethal-dose range, the differential rate of synthesis for these prote......Four proteins, alpha beta, gamma, and delta, preferentially synthesized in ultraviolet light-treated cells of Micrococcus radiodurans, were characterized in terms of their molecular weights and isoelectric points. Within the sublethal-dose range, the differential rate of synthesis...

Karyotype and nucleic acid content in Zantedeschia aethiopica Spr ...

African Journals Online (AJOL)

DR. NJ TONUKARI

2012-07-03

Jul 3, 2012 ... Analysis of karyotype, nucleic deoxyribonucleic acid (DNA) content and sodium dodecyl sulfate polyacrylamide ... base pairs) for Z. aethiopica and 1144.26 ± 0.05 picograms (equivalent to 1144.26 mega base pairs) for Z. elliottiana. ... ml ice-cold nuclei-isolation buffer A of the Partec high resolution. DNA kit ...

Time-resolved spectroscopy and fluorescence resonance energy transfer in the study of excimer laser damage of chromatin

Energy Technology Data Exchange (ETDEWEB)

Radu, L. [Department of Molecular Genetics and Radiobiology, Babes National Institute, Bucharest (Romania)], E-mail: lilianajradu@yahoo.fr; Mihailescu, I. [Department of Lasers, Laser, Plasma and Radiation Physics Institute, Bucharest (Romania); Radu, S. [Department of Computer Science, Polytechnics University, Bucharest (Romania); Gazdaru, D. [Department of Biophysics, Bucharest University (Romania)

2007-09-21

The analysis of chromatin damage produced by a 248 nm excimer laser radiation, for doses of 0.3-3 MJ/m{sup 2} was carried out by time-resolved spectroscopy and fluorescence resonance energy transfer (FRET). The chromatin was extracted from a normal and a tumoral tissue of Wistar rats. The decrease with laser dose of the relative contribution of the excited state lifetimes of ethidium bromide (EtBr) bounded to chromatin constitutes an evidence of the reduction of chromatin deoxyribonucleic acid (DNA) double-strand structure. FRET was performed from dansyl chloride to acridine orange, both coupled to chromatin. The increase of the average distance between these ligands, under the action of laser radiation, reflects a loosening of the chromatin structure. The radiosensitivity of tumor tissue chromatin is higher than that of a normal tissue. The determination of the chromatin structure modification in an excimer laser field can be of interest in laser therapy.

Time-resolved spectroscopy and fluorescence resonance energy transfer in the study of excimer laser damage of chromatin

International Nuclear Information System (INIS)

Radu, L.; Mihailescu, I.; Radu, S.; Gazdaru, D.

2007-01-01

The analysis of chromatin damage produced by a 248 nm excimer laser radiation, for doses of 0.3-3 MJ/m 2 was carried out by time-resolved spectroscopy and fluorescence resonance energy transfer (FRET). The chromatin was extracted from a normal and a tumoral tissue of Wistar rats. The decrease with laser dose of the relative contribution of the excited state lifetimes of ethidium bromide (EtBr) bounded to chromatin constitutes an evidence of the reduction of chromatin deoxyribonucleic acid (DNA) double-strand structure. FRET was performed from dansyl chloride to acridine orange, both coupled to chromatin. The increase of the average distance between these ligands, under the action of laser radiation, reflects a loosening of the chromatin structure. The radiosensitivity of tumor tissue chromatin is higher than that of a normal tissue. The determination of the chromatin structure modification in an excimer laser field can be of interest in laser therapy

Striking similarities are exhibited by two small Epstein-Barr virus-encoded ribonucleic acids and the adenovirus-associated ribonucleic acids VAI and VAII

Energy Technology Data Exchange (ETDEWEB)

Rosa, M.D.; Gottlieb, E.; Lerner, M.R.; Steitz, J.A.

1981-09-01

The nucleotide sequence of the region of the Epstein-Barr virus genome that specified two small ribonucleic acids (RNAs), EBER 1 and EBER 2, has been determined. Both of these RNAs are encoded by the right-hand 1,000 base pairs of the EcoRI J fragment of EBV deoxyribonucleic acid. EBER 1 is 166 (167) nucleotides long and EBER 2 is 172 +- 1 nucleotides long; the heterogeneity resides at the 3' termini. The EBER genes are separated by 161 base pairs and are transcribed from the same deoxyribonucleic acid strand. In vitro, both EBER genes can be transcribed by RNA polymerase III; sequences homologous to previously identified RNA polymerase III intragenic transcription control regions are present. Striking similarities are therefore apparent both between the EBERs and the two adenovirus-associated RNAs, VAI and VAII, and between the regions of the two viral genomes that specify these small RNAs. We have shown that VAII RNA as well as VAI RNA and the EBERs exist in ribonucleoprotein complexes which are precipitable by anti-La antibodies associated with systemic lupus erythematosus. Finally the authors have demonstrated that the binding of protein(s) from uninfected cells confers antigenicity on each of the four virus-encoded small RNAs.

[Nickel exposure to A549 cell damage and L-ascorbic acid interference effect].

Science.gov (United States)

Fu, Yao; Wang, Yue; Dan, Han; Zhang, Lin; Ma, Wenhan; Pan, Yulin; Wu, Yonghui

2015-05-01

Studying different concentrations of nickel smelting smoke subjects of human lung adenocarcinoma cells (A549) carcinogenic effects, discusses the influence of L-ascorbic acid protection. The A549 cells were divided into experimental and L-ascorbic acid in the intervention group. Plus exposure group concentration of nickel refining dusts were formulated 0.00, 6.25, 12.50, 25.00, 50.00, 100.00 µg/ml suspension, the intervention group on the basis of the added exposure group containing L-ascorbic acid (100 mmol/L), contact 24 h. Detection of cell viability by MTT assay. When the test substance concentration select 0.00, 25.00, 50.00, 100.00 µg/ml experiment for internal Flou-3 fluorescent probe to detect cell Ca²⁺ concentration, within DCFH-DA detect intracellular reactive oxygen (ROS) content, real-time quantitative PCR (real time, in the RT-PCR) was used to detect cell HIF-1α gene expression. With the increase of concentration, subjects increased cell growth inhibition rate, intracellular Ca²⁺ concentration increases, ROS content increased, HIF-1α gene expression increased, differences were statistically significant (P nickel exposure damage to cells. With subjects following exposure to nickel concentration increased, its effect on A549 cell damage increases, L-ascorbic acid cell damage caused by nickel has certain protective effect.

Evaluation of DNA damage using microwave dielectric absorption spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Hirayama, Makoto; Matuo, Youichrou; Izumi, Yoshinobu [Research Institute of Nuclear Engineering, University of Fukui, Fukui (Japan); Sunagawa, Takeyoshi [Fukui University of Technology, Fukui (Japan)

2016-12-15

Evaluation of deoxyribonucleic acid (DNA)-strand break is important to elucidate the biological effect of ionizing radiations. The conventional methods for DNA-strand break evaluation have been achieved by Agarose gel electrophoresis and others using an electrical property of DNAs. Such kinds of DNA-strand break evaluation systems can estimate DNA-strand break, according to a molecular weight of DNAs. However, the conventional method needs pre-treatment of the sample and a relatively long period for analysis. They do not have enough sensitivity to detect the strand break products in the low-dose region. The sample is water, methanol and plasmid DNA solution. The plasmid DNA pUC118 was multiplied by using Escherichia coli JM109 competent cells. The resonance frequency and Q-value were measured by means of microwave dielectric absorption spectroscopy. When a sample is located at a center of the electric field, resonance curve of the frequency that existed as a standing wave is disturbed. As a result, the perturbation effect to perform a resonance with different frequency is adopted. The resonance frequency shifted to higher frequency with an increase in a concentration of methanol as the model of the biological material, and the Q-value decreased. The absorption peak in microwave power spectrum of the double-strand break plasmid DNA shifted from the non-damaged plasmid DNA. Moreover, the sharpness of absorption peak changed resulting in change in Q-value. We confirmed that a resonance frequency shifted to higher frequency with an increase in concentration of the plasmid DNA. We developed a new technique for an evaluation of DNA damage. In this paper, we report the evaluation method of DNA damage using microwave dielectric absorption spectroscopy.

Evaluation of DNA damage using microwave dielectric absorption spectroscopy

International Nuclear Information System (INIS)

Hirayama, Makoto; Matuo, Youichrou; Izumi, Yoshinobu; Sunagawa, Takeyoshi

2016-01-01

Evaluation of deoxyribonucleic acid (DNA)-strand break is important to elucidate the biological effect of ionizing radiations. The conventional methods for DNA-strand break evaluation have been achieved by Agarose gel electrophoresis and others using an electrical property of DNAs. Such kinds of DNA-strand break evaluation systems can estimate DNA-strand break, according to a molecular weight of DNAs. However, the conventional method needs pre-treatment of the sample and a relatively long period for analysis. They do not have enough sensitivity to detect the strand break products in the low-dose region. The sample is water, methanol and plasmid DNA solution. The plasmid DNA pUC118 was multiplied by using Escherichia coli JM109 competent cells. The resonance frequency and Q-value were measured by means of microwave dielectric absorption spectroscopy. When a sample is located at a center of the electric field, resonance curve of the frequency that existed as a standing wave is disturbed. As a result, the perturbation effect to perform a resonance with different frequency is adopted. The resonance frequency shifted to higher frequency with an increase in a concentration of methanol as the model of the biological material, and the Q-value decreased. The absorption peak in microwave power spectrum of the double-strand break plasmid DNA shifted from the non-damaged plasmid DNA. Moreover, the sharpness of absorption peak changed resulting in change in Q-value. We confirmed that a resonance frequency shifted to higher frequency with an increase in concentration of the plasmid DNA. We developed a new technique for an evaluation of DNA damage. In this paper, we report the evaluation method of DNA damage using microwave dielectric absorption spectroscopy

DNA damage and genetic methylation changes caused by Cd in Arabidopsis thaliana seedlings.

Science.gov (United States)

Li, Zhaoling; Liu, Zhihong; Chen, Ruijuan; Li, Xiaojun; Tai, Peidong; Gong, Zongqiang; Jia, Chunyun; Liu, Wan

2015-09-01

Amplified fragment length polymorphism (AFLP) and methylation-sensitive amplification polymorphism (MASP) techniques are sensitive to deoxyribonucleic acid (DNA) damage and genetic methylation, respectively. Using these 2 techniques, Arabidopsis thaliana cultured with 0 mg/L (control), 0.5 mg/L, 1.5 mg/L, and 5.0 mg/L Cd(2+) for 16 d was used to analyze the DNA damage and methylation changes as a result of cadmium (Cd). The DNA was amplified by 14 AFLP primer pairs and 13 MSAP primer combinations. In the AFLP experiment, 62 polymorphic sites were found in the patterns of 11 primer combinations and a total of 1116 fragments were obtained in these patterns. There were no polymorphic bands in the remaining 3 pairs. The proportions of polymorphic sites in the 0.5-mg/L Cd(2+) and 5.0-mg/L Cd(2+) treatments were significantly different. Seven polymorphic fragments were then separated and successfully sequenced, yielding 6 nucleobase substitutions and 1 nucleobase deletion. Similarly, in the MSAP experiment, the MSAP% and number of demethylated-type bands were unchanged after Cd treatment, but the number of methylated-type bands was increased significantly in the 5.0-mg/L Cd(2+) treatment group, a finding that may be associated with the AFLP results. The polymorphic bands were also sequenced and the functions of their homologous genes were determined. The DNA damage and methylation changes may be the primary cause of certain pathology changes as a result of Cd uptake in plants. © 2015 SETAC.

Dietary Berries and Ellagic Acid Prevent Oxidative DNA Damage and Modulate Expression of DNA Repair Genes

Directory of Open Access Journals (Sweden)

Ramesh C. Gupta

2008-03-01

Full Text Available DNA damage is a pre-requisite for the initiation of cancer and agents that reduce this damage are useful in cancer prevention. In this study, we evaluated the ability of whole berries and berry phytochemical, ellagic acid to reduce endogenous oxidative DNA damage. Ellagic acid was selected based on > 95% inhibition of 8-oxodeoxyguosine (8-oxodG and other unidentified oxidative DNA adducts induced by 4-hydroxy-17B;-estradiol and CuCl2 in vitro. Inhibition of the latter occurred at lower concentrations (10 u(microM than that for 8-oxodG (100 u(microM. In the in vivo study, female CD-1 mice (n=6 were fed either a control diet or diet supplemented with ellagic acid (400 ppm and dehydrated berries (5% w/w with varying ellagic acid contents -- blueberry (low, strawberry (medium and red raspberry (high, for 3 weeks. Blueberry and strawberry diets showed moderate reductions in endogenous DNA adducts (25%. However, both red raspberry and ellagic acid diets showed a significant reduction of 59% (p < 0.001 and 48% (p < 0.01, respectively. Both diets also resulted in a 3-8 fold over-expression of genes involved in DNA repair such as xeroderma pigmentosum group A complementing protein (XPA, DNA excision repair protein (ERCC5 and DNA ligase III (DNL3. These results suggest that red raspberry and ellagic acid reduce endogenous oxidative DNA damage by mechanisms which may involve increase in DNA repair.

Potent Antioxidative Activity of Lycopene: A Potential Role in Scavenging Hypochlorous Acid †

OpenAIRE

Pennathur, Subramaniam; Maitra, Dhiman; Byun, Jaeman; Sliskovic, Inga; Abdulhamid, Ibrahim; Saed, Ghassan M.; Diamond, Michael P.; Abu-Soud, Husam M.

2010-01-01

Lycopene, a carotenoid found in tomatoes, is a proven anti-oxidant that may lower the risk of certain disorders including heart disease and cancer. Hypochlorous acid (HOCl) is an oxidant linked to tissue oxidation in cardiovascular disease and other inflammatory disorders through its ability to modify proteins, deoxyribonucleic acid, ribonucleic acid and lipids. Here we show that lycopene can function as a potent scavenger of HOCl at a wide range of concentrations that span various pathophysi...

Effects of branched-chain amino acids supplementation on both plasma amino acids concentration and muscle energetics changes resulting from muscle damage: A randomized placebo controlled trial.

Science.gov (United States)

Fouré, Alexandre; Nosaka, Kazunori; Gastaldi, Marguerite; Mattei, Jean-Pierre; Boudinet, Hélène; Guye, Maxime; Vilmen, Christophe; Le Fur, Yann; Bendahan, David; Gondin, Julien

2016-02-01

Branched-chain amino acids promote muscle-protein synthesis, reduce protein oxidation and have positive effects on mitochondrial biogenesis and reactive oxygen species scavenging. The purpose of the study was to determine the potential benefits of branched-chain amino acids supplementation on changes in force capacities, plasma amino acids concentration and muscle metabolic alterations after exercise-induced muscle damage. (31)P magnetic resonance spectroscopy and biochemical analyses were used to follow the changes after such damage. Twenty six young healthy men were randomly assigned to supplemented branched-chain amino acids or placebo group. Knee extensors maximal voluntary isometric force was assessed before and on four days following exercise-induced muscle damage. Concentrations in phosphocreatine [PCr], inorganic phosphate [Pi] and pH were measured during a standardized rest-exercise-recovery protocol before, two (D2) and four (D4) days after exercise-induced muscle damage. No significant difference between groups was found for changes in maximal voluntary isometric force (-24% at D2 and -21% at D4). Plasma alanine concentration significantly increased immediately after exercise-induced muscle damage (+25%) in both groups while concentrations in glycine, histidine, phenylalanine and tyrosine decreased. No difference between groups was found in the increased resting [Pi] (+42% at D2 and +34% at D4), decreased resting pH (-0.04 at D2 and -0.03 at D4) and the slower PCr recovery rate (-18% at D2 and -24% at D4). The damaged muscle was not able to get benefits out of the increased plasma branched-chain amino acids availability to attenuate changes in indirect markers of muscle damage and muscle metabolic alterations following exercise-induced muscle damage. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

An Investigation into the Association between DNA Damage and Dietary Fatty Acid in Men with Prostate Cancer

Directory of Open Access Journals (Sweden)

Karen S. Bishop

2015-01-01

Full Text Available Prostate cancer is a growing problem in New Zealand and worldwide, as populations adopt a Western style dietary pattern. In particular, dietary fat is believed to be associated with oxidative stress, which in turn may be associated with cancer risk and development. In addition, DNA damage is associated with the risk of various cancers, and is regarded as an ideal biomarker for the assessment of the influence of foods on cancer. In the study presented here, 20 men with prostate cancer adhered to a modified Mediterranean style diet for three months. Dietary records, blood fatty acid levels, prostate specific antigen, C-reactive protein and DNA damage were assessed pre- and post-intervention. DNA damage was inversely correlated with dietary adherence (p = 0.013 and whole blood monounsaturated fatty acids (p = 0.009 and oleic acid (p = 0.020. DNA damage was positively correlated with the intake of dairy products (p = 0.043, red meat (p = 0.007 and whole blood omega-6 polyunsaturated fatty acids (p = 0.015. Both the source and type of dietary fat changed significantly over the course of the dietary intervention. Levels of DNA damage were correlated with various dietary fat sources and types of dietary fat.

The role of artichoke leaf tincture (Cynara scolymus) in the suppression of DNA damage and atherosclerosis in rats fed an atherogenic diet.

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Bogavac-Stanojevic, Natasa; Kotur Stevuljevic, Jelena; Cerne, Darko; Zupan, Janja; Marc, Janja; Vujic, Zorica; Crevar-Sakac, Milkica; Sopic, Miron; Munjas, Jelena; Radenkovic, Miroslav; Jelic-Ivanovic, Zorana

2018-12-01

Polyphenols and flavonoids in artichoke leaf tincture (ALT) protect cells against oxidative damage. We examined ALT effects on deoxyribonucleic acid (DNA) damage and lipid profiles in rat plasma and gene expression in rat aorta [haemeoxygenase-1 (HO1), haemeoxygenase-2 (HO2), NADPH oxidase 4 (NOX-4), monocyte chemoattractant protein-1 (MCP-1) and nuclear factor (erythroid-derived 2)-like 2 (Nrf2)]. Eighteen male Wistar albino rats were divided into three groups (n = 6/group): The control group (CG) was fed with standard pellet chow for 11 weeks; the AD group was fed for a similar period of time with pellet chow supplemented with 2% cholesterol, 3% sunflower oil and 1% sodium cholate. The ADA group was fed with pellet chow (for 1 week), the atherogenic diet (see above) for the following 4 weeks and then with ALT (0.1 mL/kg body weight) and atherogenic diet for 6 weeks. According to HPLC analysis, the isolated main compounds in ALT were chlorogenic acid, caffeic acid, isoquercitrin and rutin. Normalized HO-1 [0.11 (0.04-0.24)] and MCP-1 [0.29 (0.21-0.47)] mRNA levels and DNA scores [12.50 (4.50-36.50)] were significantly lower in the ADA group than in the AD group [0.84 (0.35-2.51)], p = 0.021 for HO-1 [0.85 (0.61-3.45)], p = 0.047 for MCP-1 and [176.5 (66.50-221.25)], p = 0.020 for DNA scores. HO-1 mRNA was lower in the ADA group than in the CG group [0.30 (0.21-0.71), p = 0.049]. Supplementation with ALT limited the effects of the atherogenic diet through reduced MCP-1 expression, thereby preventing oxidative damage.

Quantitative determination of deoxyribonucleic acid in rat brain

Science.gov (United States)

Penn, N. W.; Suwalski, R.

1969-01-01

1. A procedure is given for spectrophotometric analysis of rat brain DNA after its resolution into component bases. Amounts of tissue in the range 50–100mg. can be used. 2. The amount of DNA obtained by the present method is 80% greater than that reported for rat brain by a previous procedure specific for DNA thymine. Identity of the material is established by the base ratios of purines and pyrimidines. The features responsible for the higher yield are the presence of dioxan during alkaline hydrolysis of tissue, the determination of the optimum concentration of potassium hydroxide in this step and omission of organic washes of the initial acid-precipitated residues. 3. The requirement for dioxan during alkaline hydrolysis suggests a possible association of brain DNA with lipid. The concentration of potassium hydroxide that gives maximum yield is 0·1m, indicating that there may be internucleotide linkages in this DNA that are more sensitive to alkali than those of liver or thymus DNA. 4. This procedure gives low yields of DNA from liver. It is not suitable for analysis of the DNA from this tissue. PMID:5353529

Fluorescence quenching of graphene oxide combined with the site-specific cleavage of restriction endonuclease for deoxyribonucleic acid demethylase activity assay

Energy Technology Data Exchange (ETDEWEB)

Ji, Lijuan; Qian, Yingdan; Wu, Ping; Zhang, Hui; Cai, Chenxin, E-mail: cxcai@njnu.edu.cn

2015-04-15

Highlights: • An approach for sensitive and selective DNA demethylase activity assay is reported. • This assay is based on the fluorescence quenching of GO and site-specific cleavage of endonuclease. • It can determine as low as 0.05 ng mL{sup −1} of MBD2 with a linear range of 0.2–300 ng mL{sup −1}. • It has an ability to recognize MBD2 from other possibly coexisting proteins and cancer cell extracts. • It can avoid false signals, requiring no bisulfite conversion, PCR amplification, radioisotope-labeling. - Abstract: We report on the development of a sensitive and selective deoxyribonucleic acid (DNA) demethylase (using MBD2 as an example) activity assay by coupling the fluorescence quenching of graphene oxide (GO) with the site-specific cleavage of HpaII endonuclease to improve the selectivity. This approach was developed by designing a single-stranded probe (P1) that carries a binding region to facilitate the interaction with GO, which induces fluorescence quenching of the labeled fluorophore (FAM, 6-carboxyfluorescein), and a sensing region, which contains a hemi-methylated site of 5′-CmCGG-3′, to specifically recognize the target (T1, a 32-mer DNA from the promoter region of p53 gene) and hybridize with it to form a P1/T1 duplex. After demethylation with MBD2, the duplex can be specifically cleaved using HpaII, which releases the labeled FAM from the GO surface and results in the recovery of fluorescence. However, this cleavage is blocked by the hemi-methylation of this site. Thus, the magnitude of the recovered fluorescence signal is related to the MBD2 activity, which establishes the basis of the DNA demethylase activity assay. This assay can determine as low as ∼(0.05 ± 0.01) ng mL{sup −1} (at a signal/noise of 3) of MBD2 with a linear range of 0.2–300 ng mL{sup −1} and recognize MBD2 from other possibly coexisting proteins and cancer cell extracts. The advantage of this assay is its ability to avoid false signals and no

Enhancement of laser induced damage threshold of fused silica by acid etching combined with UV laser conditioning

International Nuclear Information System (INIS)

Chen Meng; Xiang Xia; Jiang Yong; Zu Xiaotao; Yuan Xiaodong; Zheng Wanguo; Wang Haijun; Li Xibin; Lu Haibing; Jiang Xiaodong; Wang Chengcheng

2010-01-01

Acid etching combined with UV laser conditioning is developed to enhance the laser induced damage threshold (LIDT) of fused silica. Firstly, the fused silica is etched for 1 ∼ 100 min with a buffered 1% HF solution. After acid etching, its transmittance, surface roughness and LIDT are measured. The results reveal that the fused silica has the highest LIDT and transmittance after etching for 10 min. Then UV laser (355 nm) conditioning is adopted to process the 10-min-etched fused silica. When the laser fluence is below 60% of fused silica's zero probability damage threshold, the LIDT increases gradually with the increase of laser conditioning fluence. However, the LIDT rapidly decreases to be lower than the threshold of the 10-min-etched fused silica when the conditioning fluence is up to 80% of the threshold. Proper acid etching and laser conditioning parameters will effectively enhance the laser damage resistance of fused silica. (authors)

Repair of oxidative DNA damage by amino acids.

Science.gov (United States)

Milligan, J R; Aguilera, J A; Ly, A; Tran, N Q; Hoang, O; Ward, J F

2003-11-01

Guanyl radicals, the product of the removal of a single electron from guanine, are produced in DNA by the direct effect of ionizing radiation. We have produced guanyl radicals in DNA by using the single electron oxidizing agent (SCN)2-, itself derived from the indirect effect of ionizing radiation via thiocyanate scavenging of OH. We have examined the reactivity of guanyl radicals in plasmid DNA with the six most easily oxidized amino acids cysteine, cystine, histidine, methionine, tryptophan and tyrosine and also simple ester and amide derivatives of them. Cystine and histidine derivatives are unreactive. Cysteine, methionine, tyrosine and particularly tryptophan derivatives react to repair guanyl radicals in plasmid DNA with rate constants in the region of approximately 10(5), 10(5), 10(6) and 10(7) dm3 mol(-1) s(-1), respectively. The implication is that amino acid residues in DNA binding proteins such as histones might be able to repair by an electron transfer reaction the DNA damage produced by the direct effect of ionizing radiation or by other oxidative insults.

Chromium-induced membrane damage: protective role of ascorbic acid.

Science.gov (United States)

Dey, S K; Nayak, P; Roy, S

2001-07-01

Importance of chromium as environmental toxicant is largely due to impact on the body to produce cellular toxicity. The impact of chromium and their supplementation with ascorbic acid was studied on plasma membrane of liver and kidney in male Wistar rats (80-100 g body weight). It has been observed that the intoxication with chromium (i.p.) at the dose of 0.8 mg/100 g body weight per day for a period of 28 days causes significant increase in the level of cholesterol and decrease in the level of phospholipid of both liver and kidney. The alkaline phosphatase, total ATPase and Na(+)-K(+)-ATPase activities were significantly decreased in both liver and kidney after chromium treatment, except total ATPase activity of kidney. It is suggested that chromium exposure at the present dose and duration induce for the alterations of structure and function of both liver and kidney plasma membrane. Ascorbic acid (i.p. at the dose of 0.5 mg/100 g body weight per day for period of 28 days) supplementation can reduce these structural changes in the plasma membrane of liver and kidney. But the functional changes can not be completely replenished by the ascorbic acid supplementation in response to chromium exposure. So it is also suggested that ascorbic acid (nutritional antioxidant) is useful free radical scavenger to restrain the chromium-induced membrane damage.

Renal-protective and ameliorating impacts of omega-3 fatty acids against aspartame damaged MDCK cells.

Science.gov (United States)

Pandurangan, Muthuraman; Enkhtaivan, Gansukh; Veerappan, Muthuviveganandavel; Mistry, Bhupendra; Patel, Rahul; Moon, So Hyun; Nagajyothi, Patnamsetty Chidanandha; Kim, Doo Hwan

2017-11-01

Aspartame is widely used artificial sweeteners as food additives. Several researchers have pointed that the controversial report on the use of aspartame over more than decades. Omega-3 fatty acids are essential and unsaturated fatty acids, and it plays a remarkable role in vision, intelligence, neural development, and metabolism of neurotransmitters. Therefore, the present study was aimed to investigate the effect of omega-3 fatty acids on aspartame treated renal cells. Experimental groups were divided into three such as sham control, aspartame treated, and aspartame with omega-3 fatty acids. Cell viability was determined by sulforhodamine-b assay and flow cytometric analysis. The experimental results showed that the aspartame induced altered cell viability were reduced following treatment of aspartame with omega-3 fatty acids. Altered cell morphology was recovered by omega-3 fatty acids. DNA damage appeared in the highest concentration of aspartame used in this study. DNA damage characteristics such as comet tail and tiny head sections did not appear in the omega-3 fatty acids treated cells. Several microvilli and vesicular structures were found in aspartame treated cells. Altered morphology such as rounding, microvilli, and formation of dome-like structures did not appear in the omega-3 fatty acids with aspartame treated cells. Caspase-3 mRNA and protein expression were increased in aspartame treated cells, and these levels were reduced following omega-3 fatty acids treatment. Taking all these data together, it is suggested that the omega-3 fatty acids may be a therapeutic agent to reduce the aspartame induced biochemical and morphological alterations in normal renal cells. © 2017 BioFactors, 43(6):847-857, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

Protective effect of 4-coumaric acid from UVB ray damage in the rabbit eye.

Science.gov (United States)

Lodovici, Maura; Caldini, Silvia; Morbidelli, Lucia; Akpan, Victor; Ziche, Marina; Dolara, Piero

2009-01-08

UV-induced oxidation damage seems to play a major role in a number of specific pathological conditions of intraocular tissues, such as cataract formation and retinal degeneration. Therefore, antioxidant and/or scavenger compounds might protect the eyes from UV-induced cellular damage. We previously reported that 4-coumaric acid (4-CA) is able to protect rabbit corneal-derived cells (SIRC) from UVB-induced oxidation damage. In this study we evaluated the protective effect of 4-CA against UVB-induced cell damage in rabbit cornea in vivo. Twelve male New Zealand albino rabbits were used; four rabbits were used as a control and received vehicle in one eye and 4-CA acid in the contralateral eye; eight rabbits were exposed to UVB rays (79.2mJ/cm(2)) and three days before to UV exposure each animal received 1 drop/day of vehicle in one eye and 1 drop/day of vehicle containing 4-CA (164ng) in the contralateral eye. Corneal and sclera tissues were removed and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) levels were measured. Superoxide dismutase (SOD) and xanthine oxidase (XO) activities were determined in aqueous humour. UVB-induced vessel hyper-reactivity was strongly reduced at 4 and 24h after UVB exposure after local treatment with 4-CA, 8-oxodGuo levels, a marker of oxidative DNA damage, were significantly increased (Peyes. Our results indicate that the administration of 4-CA protects eye tissues, thus reducing the harmful effect of UVB radiation at low concentration, probably through its free radical scavenging and antioxidant properties. Therefore, 4-CA may be useful in protecting the eye from free radical damage following UVB exposure from sunlight, UV lamps and welding torches.

Binding mechanisms for histamine and agmatine ligands in plasmid deoxyribonucleic acid purifications.

Science.gov (United States)

Sousa, Ângela; Pereira, Patrícia; Sousa, Fani; Queiroz, João A

2014-10-31

Histamine and agmatine amino acid derivatives were immobilized into monolithic disks, in order to combine the specificity and selectivity of the ligand with the high mass transfer and binding capacity offered by monolithic supports, to purify potential plasmid DNA biopharmaceuticals. Different elution strategies were explored by changing the type and salt concentration, as well as the pH, in order to understand the retention pattern of different plasmids isoforms The pVAX1-LacZ supercoiled isoform was isolated from a mixture of pDNA isoforms by using NaCl increasing stepwise gradient and also by ammonium sulfate decreasing stepwise gradient, in both histamine and agmatine monoliths. Acidic pH in the binding buffer mainly strengthened ionic interactions with both ligands in the presence of sodium chloride. Otherwise, for histamine ligand, pH values higher than 7 intensified hydrophobic interactions in the presence of ammonium sulfate. In addition, circular dichroism spectroscopy studies revealed that the binding and elution chromatographic conditions, such as the combination of high ionic strength with extreme pH values can reversibly influence the structural stability of the target nucleic acid. Therefore, ascending sodium chloride gradients with pH manipulation can be preferable chromatographic conditions to be explored in the purification of plasmid DNA biopharmaceuticals, in order to avoid the environmental impact of ammonium sulfate. Copyright © 2014. Published by Elsevier B.V.

Nutritional Manipulation of Primate Retinas, V: Effects of Lutein, Zeaxanthin, and n–3 Fatty Acids on Retinal Sensitivity to Blue-Light–Induced Damage

Science.gov (United States)

Barker, Felix M.; Snodderly, D. Max; Johnson, Elizabeth J.; Schalch, Wolfgang; Koepcke, Wolfgang; Gerss, Joachim

2011-01-01

Purpose. Blue-light photooxidative damage has been implicated in the etiology of age-related macular degeneration (AMD). The macular pigment xanthophylls lutein (L) and zeaxanthin (Z) and n–3 fatty acids may reduce this damage and lower the risk of AMD. This study investigated the effects of the lifelong absence of xanthophylls followed by L or Z supplementation, combined with the effects of n–3 fatty acid deficiency, on acute blue-light photochemical damage. Methods. Subjects included eight rhesus monkeys with no lifelong intake of xanthophylls and no detectable macular pigment. Of these, four had low n–3 fatty acid intake and four had adequate intakes. Control subjects had typical L, Z, and n–3 fatty acid intake. Retinas received 150-μm-diameter exposures of low-power 476-nm laser light at 0.5 mm (∼2°) eccentricity, which is adjacent to the macular pigment peak, and parafoveally at 1.5 mm (∼6°). Exposures of xanthophyll-free animals were repeated after supplementation with pure L or Z for 22 to 28 weeks. Ophthalmoscopically visible lesion areas were plotted as a function of exposure energy, with greater slopes of the regression lines indicating greater sensitivity to damage. Results. In control animals, the fovea was less sensitive to blue-light–induced damage than the parafovea. Foveal protection was absent in xanthophyll-free animals but was evident after supplementation. In the parafovea, animals low in n–3 fatty acids showed greater sensitivity to damage than animals with adequate levels. Conclusions. After long-term xanthophyll deficiency, L or Z supplementation protected the fovea from blue light–induced damage, whereas adequate n–3 fatty acid levels reduced the damage in the parafovea. PMID:21245404

Ultraviolet-B Protective Effect of Flavonoids from Eugenia caryophylata on Human Dermal Fibroblast Cells

OpenAIRE

Patwardhan, Juilee; Bhatt, Purvi

2015-01-01

Background: The exposure of skin to ultraviolet-B (UV-B) radiations leads to deoxyribonucleic acid (DNA) damage and can induce production of free radicals which imbalance the redox status of the cell and lead to increased oxidative stress. Clove has been traditionally used for its analgesic, anti-inflammatory, anti-microbial, anti-viral, and antiseptic effects. Objective: To evaluate the UV-B protective activity of flavonoids from Eugenia caryophylata (clove) buds on human dermal fibroblast c...

The effects of topically applied glycolic acid and salicylic acid on ultraviolet radiation-induced erythema, DNA damage and sunburn cell formation in human skin.

Science.gov (United States)

Kornhauser, Andrija; Wei, Rong-Rong; Yamaguchi, Yuji; Coelho, Sergio G; Kaidbey, Kays; Barton, Curtis; Takahashi, Kaoruko; Beer, Janusz Z; Miller, Sharon A; Hearing, Vincent J

2009-07-01

alpha-Hydroxy acids (alphaHAs) are reported to reduce signs of aging in the skin and are widely used cosmetic ingredients. Several studies suggest that alphaHA can increase the sensitivity of skin to ultraviolet radiation. More recently, beta-hydroxy acids (betaHAs), or combinations of alphaHA and betaHA have also been incorporated into antiaging skin care products. Concerns have also arisen about increased sensitivity to ultraviolet radiation following use of skin care products containing beta-HA. To determine whether topical treatment with glycolic acid, a representative alphaHA, or with salicylic acid, a betaHA, modifies the short-term effects of solar simulated radiation (SSR) in human skin. Fourteen subjects participated in this study. Three of the four test sites on the mid-back of each subject were treated daily Monday-Friday, for a total of 3.5 weeks, with glycolic acid (10%), salicylic acid (2%), or vehicle (control). The fourth site received no treatment. After the last treatment, each site was exposed to SSR, and shave biopsies from all four sites were obtained. The endpoints evaluated in this study were erythema (assessed visually and instrumentally), DNA damage and sunburn cell formation. Treatment with glycolic acid resulted in increased sensitivity of human skin to SSR, measured as an increase in erythema, DNA damage and sunburn cell formation. Salicylic acid did not produce significant changes in any of these biomarkers. Short-term topical application of glycolic acid in a cosmetic formulation increased the sensitivity of human skin to SSR, while a comparable treatment with salicylic acid did not.

Developing a biological dosimeter based on mitochondrial DNA

Energy Technology Data Exchange (ETDEWEB)

Adams, S; Carlisle, S M; Unrau, P; Deugau, K V [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

1996-12-31

Direct measurement of deoxyribonucleic acid (DNA) damage from ionizing radiation may be advantageous in determining radiation radiation exposures and assessing their effects on atomic radiation workers. The mitochondrial DNA molecule is one potential cellular DNA target which is: fully defined and sequenced; present in many copies per cell; not vital to cellular survival; and less subject to DNA repair than nuclear DNA. A method is described to isolate and analyse normal mitochondrial DNA. We describe the developments needed to determine DNA damage in mitochondrial DNA. The target is to make a biological dosimeter. (author). 6 refs., 3 figs.

Developing a biological dosimeter based on mitochondrial DNA

International Nuclear Information System (INIS)

Adams, S.; Carlisle, S.M.; Unrau, P.; Deugau, K.V.

1995-01-01

Direct measurement of deoxyribonucleic acid (DNA) damage from ionizing radiation may be advantageous in determining radiation radiation exposures and assessing their effects on atomic radiation workers. The mitochondrial DNA molecule is one potential cellular DNA target which is: fully defined and sequenced; present in many copies per cell; not vital to cellular survival; and less subject to DNA repair than nuclear DNA. A method is described to isolate and analyse normal mitochondrial DNA. We describe the developments needed to determine DNA damage in mitochondrial DNA. The target is to make a biological dosimeter. (author). 6 refs., 3 figs

Image analysis of epicuticular damage to foliage caused by dry deposition of the air pollutant nitric acid.

Science.gov (United States)

Padgett, Pamela E; Parry, Sally D; Bytnerowicz, Andrzej; Heath, Robert L

2009-01-01

Nitric acid vapor is produced by the same photochemical processes that produce ozone. In the laboratory, concentrated nitric acid is a strong acid and a powerful oxidant. In the environment, where the concentrations are much lower, it is an innocuous source of plant nitrogen. As an air pollutant, which mode of action does dry deposition of nitric acid follow? We investigated the effects of dry deposition of nitric acid on the foliage of four tree species native to the western United States. A novel controlled environment, fumigation system enabled a four-week exposure at concentrations consistent with ambient diurnal patterns. Scanning electron microscopy and automated image analysis revealed changes in the epicuticular wax layer during fumigation. Exposure to nitric acid resulted in a reproducible suite of damage symptoms that increased with increasing dose. Each tree species tested exhibited a unique set of damage features, including cracks, lesions, and conformation changes to epicuticular crystallite structures. Dry deposition of atmospheric nitric acid caused substantial perturbation to the epicuticular surface of all four tree species investigated, consistent with the chemical oxidation of epicuticular waxes. Automated image analysis eliminated many biases that can trouble microscopy studies. Trade names and commercial enterprises or products are mentioned solely for information. No endorsements by the U.S. Department of Agriculture are implied.

Antibacterial Effect of Gallic Acid against Aeromonas hydrophila and Aeromonas sobria Through Damaging Membrane Integrity.

Science.gov (United States)

Lu, Jing; Wang, Zhenning; Ren, Mengrou; Huang, Guoren; Fang, Baochen; Bu, Xiujuan; Liu, Yanhui; Guan, Shuang

In the study, we investigated the antibacterial activity and mechanism of gallic acid against Aeromonas hydrophila and Aeromonas sobria. Gallic acid showed strong antimicrobial activity against the two bacteria. Furthermore, the antibacterial mechanism of gallic acid (0, 3, 6, 12 mM) was performed by membrane integrity assay and scanning electron microscopy (SEM) assay. The results showed that gallic acid notably increased the released material absorption value at 260, 280 nm and electric conductivity in a dose-dependent manner. Moreover, the SEM assay showed that gallic acid induced severe shrink of bacterial intima and irregular morphology in a dose-dependent manner. The SDS-PAGE profiles further confirmed that gallic acid could damage bacterial cells. These results indicated gallic acid exhibited antibacterial effect by destroying membrane integrity of A. hydrophila and A. sobria. Hence, gallic acid has great potential as a new natural food preservative in food fresh-keeping and storage.

Zebrafish as an In Vivo Model to Assess Epigenetic Effects of Ionizing Radiation

OpenAIRE

Eva Yi Kong; Shuk Han Cheng; Kwan Ngok Yu

2016-01-01

Exposure to ionizing radiations (IRs) is ubiquitous in our environment and can be categorized into ?targeted? effects and ?non-targeted? effects. In addition to inducing deoxyribonucleic acid (DNA) damage, IR exposure leads to epigenetic alterations that do not alter DNA sequence. Using an appropriate model to study the biological effects of radiation is crucial to better understand IR responses as well as to develop new strategies to alleviate exposure to IR. Zebrafish, Danio rerio, is a sci...

UDP-glucuronosyltransferase-dependent bioactivation of clofibric acid to a DNA-damaging intermediate in mouse hepatocytes.

Science.gov (United States)

Ghaoui, Roula; Sallustio, Benedetta C; Burcham, Philip C; Fontaine, Frank R

2003-05-06

Glucuronidation of a number of carboxyl-containing drugs generates reactive acyl glucuronide metabolites. These electrophilic species alkylate cell proteins and may be implicated in the pathogenesis of a number of toxic syndromes seen in patients receiving the parent aglycones. Whether acyl glucuronides also attack nuclear DNA is unknown, although the acyl glucuronide formed from clofibric acid was recently found to decrease the transfection efficiency of phage DNA and generate strand breaks in plasmid DNA in vitro. To determine if such a DNA damage occurs within a cellular environment, the comet assay (i.e. single-cell gel electrophoresis) was used to detect DNA lesions in the nuclear genome of isolated mouse hepatocytes cultured with clofibric acid. Overnight exposure to 50 microM and higher concentrations of clofibric acid produced concentration-dependent increases in the comet areas of hepatocyte nuclei, with 1 mM clofibrate producing a 3.6-fold elevation over controls. These effects closely coincided with culture medium concentrations of the glucuronide metabolite formed from clofibric acid, 1-O-beta-clofibryl glucuronide. Consistent with a role for glucuronidation in the DNA damage observed, the glucuronidation inhibitor borneol diminished glucuronide formation from 100 microM clofibrate by 98% and returned comet areas to baseline levels. Collectively, these results suggest that the acyl glucuronide formed from clofibric acid is capable of migrating from its site of formation within the endoplasmic reticulum to generate strand nicks in nuclear DNA.

Effects of formic acid hydrolysis on the quantitative analysis of radiation-induced DNA base damage products assayed by gas chromatography/mass spectrometry

International Nuclear Information System (INIS)

Swarts, S.G.; Smith, G.S.; Miao, L.; Wheeler, K.T.

1996-01-01

Gas chromatography/mass spectrometry (GC/ MS-SIM) is an excellent technique for performing both qualitative and quantitative analysis of DNA base damage products that are formed by exposure to ionizing radiation or by the interaction of intracellular DNA with activated oxygen species. This technique commonly uses a hot formic acid hydrolysis step to degrade the DNA to individual free bases. However, due to the harsh nature of this degradation procedure, the quantitation of DNA base damage products may be adversely affected. Consequently, we examined the effects of various formic acid hydrolysis procedures on the quantitation of a number of DNA base damage products and identified several factors that can influence this quantitation. These factors included (1) the inherent acid stabilities of both the lesions and the internal standards; (2) the hydrolysis temperature; (3) the source and grade of the formic acid; and (4) the sample mass during hydrolysis. Our data also suggested that the N, O-bis (trimethylsilyl)trifluoroacetamide (BSTFA) derivatization efficiency can be adversely affected, presumably by trace contaminants either in the formic acid or from the acid-activated surface of the glass derivatization vials. Where adverse effects were noted, modifications were explored in an attempt to improve the quantitation of these DNA lesions. Although experimental steps could be taken to minimize the influence of these factors on the quantitation of some base damage products, no single procedure solved the quantitation problem for all base lesions. However, a significant improvement in the quantitation was achieved if the relative molecular response factor (RMRF) values for these lesions were generated with authentic DNA base damage products that had been treated exactly like the experimental samples. (orig.)

Ultra-Sensitive Biological Detection via Nanoparticle-Based Magnetically Amplified Surface Plasmon Resonance (Mag-SPR) Techniques

Science.gov (United States)

2008-10-08

surfactant such as hexadecyltrimethyl ammonium bromide (CTMA). And also CTMA- polymethacrylic acid (PMA), CTMA-Polyglutamic acid were synthesized as reference...rich world of naturally occurring biomaterials probably none is more important and more fundamental than DNA (deoxyribonucleic acid ), the polymeric...deoxyribonucleic acid gate dielectric," Journal of Applied Physics, vol. 100, p. 024514, 2006. [3] C. H. Lee, E.-D. Do, Y.-W. Kwon, D.-H. Choi, J.-I. Jin

Helicase-dependent amplification of nucleic acids.

Science.gov (United States)

Cao, Yun; Kim, Hyun-Jin; Li, Ying; Kong, Huimin; Lemieux, Bertrand

2013-10-11

Helicase-dependent amplification (HDA) is a novel method for the isothermal in vitro amplification of nucleic acids. The HDA reaction selectively amplifies a target sequence by extension of two oligonucleotide primers. Unlike the polymerase chain reaction (PCR), HDA uses a helicase enzyme to separate the deoxyribonucleic acid (DNA) strands, rather than heat denaturation. This allows DNA amplification without the need for thermal cycling. The helicase used in HDA is a helicase super family II protein obtained from a thermophilic organism, Thermoanaerobacter tengcongensis (TteUvrD). This thermostable helicase is capable of unwinding blunt-end nucleic acid substrates at elevated temperatures (60° to 65°C). The HDA reaction can also be coupled with reverse transcription for ribonucleic acid (RNA) amplification. The products of this reaction can be detected during the reaction using fluorescent probes when incubations are conducted in a fluorimeter. Alternatively, products can be detected after amplification using a disposable amplicon containment device that contains an embedded lateral flow strip. Copyright © 2013 John Wiley & Sons, Inc.

Bilateral lesions of suprachiasmatic nuclei affect circadian rhythms in [3H]-thymidine incorporation into deoxyribonucleic acid in mouse intestinal tract, mitotic index of corneal epithelium, and serum corticosterone

International Nuclear Information System (INIS)

Scheving, L.E.; Tsai, T.H.; Powell, E.W.; Pasley, J.N.; Halberg, F.; Dunn, J.

1983-01-01

Investigations into the role of the suprachiasmatic nuclei (SCN) in the coordination of circadian rhythms have presented differing results. Several reports have shown that ablation of the suprachiasmatic nuclei (SCNA) alters the phase and amplitude of rhythms but does not abolish them. The present study investigates the effect of SCNA on the rhythms in cell proliferation in various regions of the intestinal tract as measured by the incorporation of [ 3 H]-thymidine into deoxyribonucleic acid, in the mitotic activity of the corneal epithelium, and in serum corticosterone levels. The study involved mice with verified lesions of the SCN (six to 13 mice per time point) and control groups of both sham-operated and unoperated mice (seven of each per time point). The mice were killed in groups that represented seven time points over a single 24 hr span (3 hr intervals with the 0800 hr sampled both at start and end of the series). The tissues examined were the tongue, esophagus, gastric stomach, and colon for DNA synthesis, the corneal epithelium for mitotic index, and blood serum for corticosterone level. The most consistent result of SCNA was a phase advance in the rhythms in cell proliferation in the tongue, esophagus, gastric stomach, colon, and corneal epithelium. A reduction in rhythm amplitude occurred in the tongue, esophagus, and corneal epithelium; however, there was an amplitude increase for the stomach, colon, and serum corticosterone. The mesor (rhythm-adjusted mean) was increased by SCNA in all tissues except the corneal epithelium. These findings further support the role of the suprachiasmatic nuclear area in the control of rhythms in cell proliferation and corticosterone production, by acting as a ''phase-resetter'' and as a modulator of rhythm amplitude

Detection, characterization and measure of a new radiation-induced damage in isolated and cellular DNA

International Nuclear Information System (INIS)

Regulus, P.

2006-10-01

Deoxyribonucleic acid (DNA) contains the genetic information and chemical injury to this macromolecule may have severe biological consequences. We report here the detection of 4 new radiation-induced DNA lesions by using a high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) approach. For that purpose, the characteristic fragmentation of most 2'-deoxy-ribo nucleosides, the loss of 116 Da corresponding to the loss of the 2-deoxyribose moiety, was used in the so-called neutral loss mode of the HPLC-MS/MS. One of the newly detected lesions, named dCyd341 because it is a 2'-deoxycytidine modification exhibiting a molecular weight of 341 Da, was also detected in cellular DNA. Characterization of this modified nucleoside was performed using NMR and exact mass determination of the product obtained by chemical synthesis. A mechanism of formation was then proposed, in which the first event is the H-abstraction at the C4 position of a 2-deoxyribose moiety. Then, the sugar modification produced exhibits a reactive aldehyde that, through reaction with a vicinal cytosine base, gives rise to dCyd341. dCyd341 could be considered as a complex damage since its formation involves a DNA strand break and a cross-link between a damaged sugar residue and a vicinal cytosine base located most probably on the complementary DNA strand. In addition to its characterization, preliminary biological studies revealed that cells are able to remove the lesion from DNA. Repair studies have revealed the ability of cells to excise the lesion. Identification of the repair systems involved could represent an interesting challenge. (author)

Homology among tet determinants in conjugative elements of streptococci

Energy Technology Data Exchange (ETDEWEB)

Smith, M.D.; Hazum, S.; Guild, W.R.

1981-10-01

A mutation to tetracycline sensitivity in a resistant strain of Streptococcus pneumoniae was shown by several criteria to be due to a point mutation in the conjugative o(cat-tet) element found in the chromosomes of strains derived from BM6001, a clinical strain resistant to tetracycline and chloramphenicol. Strains carrying the mutation were transformed back to tetracycline resistance with the high efficiency of a point marker by donor deoxyribonucleic acids from its ancestral strain and from nine other clinical isolates of pneumococcus and by deoxyribonucleic acids from Group D Streptococcus faecalis and Group B Streptococcus agalactiae strains that also carry conjugative tet elements in their chromosomes. It was not transformed to resistance by tet plasmid deoxyribonucleic acids from either gram-negative or gram-positive species, except for one that carried transposon TN916, the conjugative tet element present in the chromosomes of some S. faecalis strains. The results showed that the tet determinants in conjugative elements of several streptococcal species share a high degree of deoxyribonucleic acid sequence homology and suggested that they differ from other tet genes.

Anti-inflammatory and ameliorative effects of gallic acid on fluoxetine-induced oxidative stress and liver damage in rats.

Science.gov (United States)

Karimi-Khouzani, Omid; Heidarian, Esfandiar; Amini, Sayed Asadollah

2017-08-01

Fluoxetine-induced liver damage is a cause of chronic liver disease. In the present study the hepatoprotective effects of gallic acid against fluoxetine-induced liver damage were examined. Forty-eight male rats were divided into six groups as follow: group 1, the control group; group 2, rats receiving fluoxetine (24mg/kg bw daily, po) without treatment; group 3, rats receiving 24mg/kg bw fluoxetine, treated with 50mg/kg bw silymarin and groups 4, 5, and 6 in which gallic acid (50, 100, and 200mg/kg bw, po, respectively) was prescribed after the consumption of fluoxetine. The histopathological changes of hepatic tissues were checked out. Fluoxetine caused a significant increase in the levels of serum glutamate oxaloacetate transaminase (GOT), serum glutamate pyruvate transaminase (GPT), lipid profiles, urea, fasting blood sugar (FBS), creatinine (Cr), protein carbonyl (PC) content, malondialdehyde (MDA), and liver TNF-α as an inflammatory element. Also, the obtained results of group 2 revealed a significant decline in ferric reducing ability of plasma (FRAP), liver catalase (CAT), superoxide dismutase (SOD), and vitamin C levels. The treatment with gallic acid showed significant ameliorations in abnormalities of fluoxetine-induced liver injury as represented by the improvement of hepatic CAT, SOD activities, vitamin C levels, serum biochemical parameters, and histopathological changes, in addition to the recovery of antioxidant defense system status. Gallic acid has inhibitory effects on fluoxetine-induced liver damage. The effect of gallic acid is derived from free radical scavenging properties and the anti-inflammatory effect related to TNF-α. Copyright © 2017. Published by Elsevier Urban & Partner Sp. z o.o.

Genetic Transformation of Streptococcus mutans

OpenAIRE

Perry, Dennis; Kuramitsu, Howard K.

1981-01-01

Three strains of Streptococcus mutans belonging to serotypes a, c, and f were transformed to streptomycin resistance by deoxyribonucleic acids derived from homologous and heterologous streptomycin-resistant strains of S. mutans and Streptococcus sanguis strain Challis. Homologous transformation of S. mutans was less efficient than heterologous transformation by deoxyribonucleic acids from other strains of S. mutans.

Nucleosome acidic patch promotes RNF168- and RING1B/BMI1-dependent H2AX and H2A ubiquitination and DNA damage signaling.

Directory of Open Access Journals (Sweden)

Justin W Leung

2014-03-01

Full Text Available Histone ubiquitinations are critical for the activation of the DNA damage response (DDR. In particular, RNF168 and RING1B/BMI1 function in the DDR by ubiquitinating H2A/H2AX on Lys-13/15 and Lys-118/119, respectively. However, it remains to be defined how the ubiquitin pathway engages chromatin to provide regulation of ubiquitin targeting of specific histone residues. Here we identify the nucleosome acid patch as a critical chromatin mediator of H2A/H2AX ubiquitination (ub. The acidic patch is required for RNF168- and RING1B/BMI1-dependent H2A/H2AXub in vivo. The acidic patch functions within the nucleosome as nucleosomes containing a mutated acidic patch exhibit defective H2A/H2AXub by RNF168 and RING1B/BMI1 in vitro. Furthermore, direct perturbation of the nucleosome acidic patch in vivo by the expression of an engineered acidic patch interacting viral peptide, LANA, results in defective H2AXub and RNF168-dependent DNA damage responses including 53BP1 and BRCA1 recruitment to DNA damage. The acidic patch therefore is a critical nucleosome feature that may serve as a scaffold to integrate multiple ubiquitin signals on chromatin to compose selective ubiquitinations on histones for DNA damage signaling.

Superimposed Code Theoretic Analysis of Deoxyribonucleic Acid (DNA) Codes and DNA Computing

Science.gov (United States)

2010-01-01

DNA strand and its Watson - Crick complement can be used to perform mathematical computation. This research addresses how the...Acid dsDNA double stranded DNA MOSAIC Mobile Stream Processing Cluster PCR Polymerase Chain Reaction RAM Random Access Memory ssDNA single stranded DNA WC Watson – Crick A Adenine C Cytosine G Guanine T Thymine ...are 5′→3′ and strands with strikethrough are 3′→5′. A dsDNA duplex formed between a strand and its reverse complement is called a

Detection of autoimmune antibodies in localized scleroderma by synthetic oligonucleotide antigens

DEFF Research Database (Denmark)

Samuelsen, Simone; Jørgensen, Christian Damsgaard; Mellins, Elizabeth D

2018-01-01

In this study, we developed a series of synthetic oligonucleotides that allowed us to investigate the details on the antigen recognition by autoimmune antibodies in localized scleroderma subjects. Besides dramatically improved analytical specificity of the assay, our data suggests a potential...... linking for antibodies to DNA to the biological status of disease state in localized scleroderma. Moreover, introducing chemical modifications into short synthetic deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) molecules completely changed the binding titers of corresponding antibodies...... and their clinical relevance. The strongest observed effect was registered for the localized scleroderma skin damage index (LoSDI) on the IgG antibodies to TC dinucleotide-rich double-stranded antigen (p

Protective effect of 4-coumaric acid from UVB ray damage in the rabbit eye

International Nuclear Information System (INIS)

Lodovici, Maura; Caldini, Silvia; Morbidelli, Lucia; Akpan, Victor; Ziche, Marina; Dolara, Piero

2009-01-01

UV-induced oxidation damage seems to play a major role in a number of specific pathological conditions of intraocular tissues, such as cataract formation and retinal degeneration. Therefore, antioxidant and/or scavenger compounds might protect the eyes from UV-induced cellular damage. We previously reported that 4-coumaric acid (4-CA) is able to protect rabbit corneal-derived cells (SIRC) from UVB-induced oxidation damage. In this study we evaluated the protective effect of 4-CA against UVB-induced cell damage in rabbit cornea in vivo. Twelve male New Zealand albino rabbits were used; four rabbits were used as a control and received vehicle in one eye and 4-CA acid in the contralateral eye; eight rabbits were exposed to UVB rays (79.2 mJ/cm 2 ) and three days before to UV exposure each animal received 1 drop/day of vehicle in one eye and 1 drop/day of vehicle containing 4-CA (164 ng) in the contralateral eye. Corneal and sclera tissues were removed and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) levels were measured. Superoxide dismutase (SOD) and xanthine oxidase (XO) activities were determined in aqueous humour. UVB-induced vessel hyper-reactivity was strongly reduced at 4 and 24 h after UVB exposure after local treatment with 4-CA, 8-oxodGuo levels, a marker of oxidative DNA damage, were significantly increased (P < 0.05) in sclera and cornea by UVB irradiation, but when 4-CA was administered to the conjunctiva in a buffered solution once a day for 3 d before and 6 d after UVB exposure, levels of 8-oxodGuo were similar to controls and significantly reduced (P < 0.05) compared to UVB-treated corneas. XO activity in the aqueous humour was significantly increased. The administration of 4-CA for 3 d before and 6 d after UVB irradiation induced a small but significant (P < 0.05) reduction of XO compared with control eyes. Our results indicate that the administration of 4-CA protects eye tissues, thus reducing the harmful effect of UVB radiation at low

Nanotechnology: Threats and Deterrent Opportunities by 2035

Science.gov (United States)

2010-02-17

22. 17 James Watson and Francis Crick discovered the structure of Deoxyribonucleic acid ( DNA ) in 1953. 18 Self-replication is when nanoscale machine...which then improves researchers’ understanding of critical, computationally intensive fields of study like DNA .17 These complementary scientific and...researchers’ clarity on critical medical issues like Deoxyribonucleic acid ( DNA ). 102 Omar Khayyam, Rubaiyat of Omar Khayyam (NY: Random House, 1947

Effect of the methyl gallate on the damage produced by radiation in leucocytes of peripheral blood of In vivo mouse

International Nuclear Information System (INIS)

Zarco M, A.

2007-01-01

The ionizing radiation produces a great variety of lesions in the deoxyribonucleic acid (DNA) through the formation of free radicals (RL), reason why the study about those made up with possible radioprotective property has been increased. The methyl gallate (MeG) it is an antioxidant derived of plants with capacity to capture RL. The objective of the present work was to determine the effect of the methyl gallate on the damage in the DNA taken place by gamma radiation in leukocytes of peripheral blood of in vivo mouse. The experimental design consisted of 4 groups of mice: It has a witness of the solvent group, dimethylsulfoxide (DMSO), in which was administer by intraperitoneal via 0.4 mL of a solution 1:8 of DMSO: H 2 O; a second group, denominated MeG witness, it was administered intraperitoneally with a dose of 0.1 μ moles/g of weight. Another group was used as radiation witness, reason why it was only treated with 1 Gray (Gy) of gamma radiation coming from a cobalt 60 source. At last, the group denominated problem it was administered with 0.1 μ moles of MeG/g of corporal weight 30 previous minutes to the irradiation with 1 Gy. In the comparison of the damage and repair curves obtained with the unicellular in gel electrophoresis technique among the irradiated groups, it was determined that there is one significant reduction of 15% in the DNA damage observed to the two minutes postradiation in the problem group with respect to the radiation witness. It was concluded that this decrease is due to the antioxidant effect of the methyl gallate and that therefore this compound has possibilities to act as radioprotector. (Author)

Persistence of DNA damage following exposure of human bladder cells to chronic monomethylarsonous acid

International Nuclear Information System (INIS)

Wnek, S.M.; Medeiros, M.K.; Eblin, K.E.; Gandolfi, A.J.

2009-01-01

Malignant transformation was demonstrated in UROtsa cells following 52-weeks of exposure to 50 nM monomethylarsonous acid (MMA III ); the result was the malignantly transformed cell line, URO-MSC. URO-MSC cells were used to study the induction of DNA damage and the alteration of DNA repair enzymes in both the presence of MMA III [URO-MSC(+)] and after subsequent removal of MMA III [URO-MSC(-)] following chronic, low-level exposure. In the presence of MMA III , URO-MSC(+) cells demonstrated a sustained increase in DNA damage following 12-weeks of exposure; in particular, a significant increase in DNA single-strand breaks at 12-weeks of exposure consistently elevated through 52 weeks. The persistence of DNA damage in URO-MSC cells was assessed after a 2-week removal of MMA III . URO-MSC(-) cells demonstrated a decrease in DNA damage compared to URO-MSC(+); however, DNA damage in URO-MSC(-) remained significantly elevated when compared to untreated UROtsa and increased in a time-dependent manner. Reactive oxygen species (ROS) were demonstrated to be a critical component in the generation of DNA damage determined through the incubation of ROS scavengers with URO-MSC cells. Poly (ADP-ribose) polymerase (PARP) is a key repair enzyme in DNA single-strand break repair. URO-MSC(+) resulted in a slight increase in PARP activity after 36-weeks of MMA III exposure, suggesting the presence of MMA III is inhibiting the increase in PARP activity. In support, PARP activity in URO-MSC(-) increased significantly, coinciding with a subsequent decrease in DNA damage demonstrated in URO-MSC(-) compared to URO-MSC(+). These data demonstrate that chronic, low-level exposure of UROtsa cells to 50 nM MMA III results in: the induction of DNA damage that remains elevated upon removal of MMA III ; increased levels of ROS that play a role in MMA III induced-DNA damage; and decreased PARP activity in the presence of MMA III .

An unusual mode of DNA duplex association: Watson-Crick interaction of all-purine deoxyribonucleic acids.

Science.gov (United States)

Battersby, Thomas R; Albalos, Maria; Friesenhahn, Michel J

2007-05-01

Nucleic acid duplexes associating through purine-purine base pairing have been constructed and characterized in a remarkable demonstration of nucleic acids with mixed sequence and a natural backbone in an alternative duplex structure. The antiparallel deoxyribose all-purine duplexes associate specifically through Watson-Crick pairing, violating the nucleobase size-complementarity pairing convention found in Nature. Sequence-specific recognition displayed by these structures makes the duplexes suitable, in principle, for information storage and replication fundamental to molecular evolution in all living organisms. All-purine duplexes can be formed through association of purines found in natural ribonucleosides. Key to the formation of these duplexes is the N(3)-H tautomer of isoguanine, preferred in the duplex, but not in aqueous solution. The duplexes have relevance to evolution of the modern genetic code and can be used for molecular recognition of natural nucleic acids.

Lipoic acid in combination with a chelator ameliorates lead-induced peroxidative damages in rat kidney

Energy Technology Data Exchange (ETDEWEB)

Sivaprasad, R.; Nagaraj, M.; Varalakshmi, P. [Department of Medical Biochemistry, University of Madras (Taramani), Chennai 600 113 (India)

2002-08-01

The deleterious effect of lead has been attributed to lead-induced oxidative stress with the consequence of lipid peroxidation. The present study was designed to investigate the combined effect of DL-{alpha}-lipoic acid (LA) and meso-2,3-dimercaptosuccinic acid (DMSA) on lead-induced peroxidative damages in rat kidney. The increase in peroxidated lipids in lead-poisoned rats was accompanied by alterations in antioxidant defence systems. Lead acetate (Pb, 0.2%) was administered in drinking water for 5 weeks to induce lead toxicity. LA (25 mg/kg body weight per day i.p) and DMSA (20 mg/kg body weight per day i.p) were administered individually and also in combination during the sixth week. Nephrotoxic damage was evident from decreases in the activities of {gamma}-glutamyl transferase and N-acetyl {beta}-D-glucosaminidase, which were reversed upon combined treatment with LA and DMSA. Rats subjected to lead intoxication showed a decline in the thiol capacity of the cell, accompanied by high malondialdehyde levels along with lowered activities of catalase, superoxide dismutase, glutathione peroxidase and glutathione metabolizing enzymes (glutathione reductase, glucose-6-phosphate dehydrogenase, glutathione-S-transferase). Supplementation with LA as a sole agent showed considerable changes over oxidative stress parameters. The study has highlighted the combined effect of both drugs as being more effective in reversing oxidative damage by bringing about an improvement in the reductive status of the cell. (orig.)

Low Protein Diet Inhibits Uric Acid Synthesis and Attenuates Renal Damage in Streptozotocin-Induced Diabetic Rats

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Jianmin Ran

2014-01-01

Full Text Available Aim. Several studies indicated that hyperuricemia may link to the worsening of diabetic nephropathy (DN. Meanwhile, low protein diet (LPD retards exacerbation of renal damage in chronic kidney disease. We then assessed whether LPD influences uric acid metabolism and benefits the progression of DN in streptozotocin- (STZ- induced diabetic rats. Methods. STZ-induced and control rats were both fed with LPD (5% and normal protein diet (18%, respectively, for 12 weeks. Vital signs, blood and urinary samples for UA metabolism were taken and analyzed every 3 weeks. Kidneys were removed at the end of the experiment. Results. Diabetic rats developed into constantly high levels of serum UA (SUA, creatinine (SCr and 24 h amounts of urinary albumin excretion (UAE, creatintine (UCr, urea nitrogen (UUN, and uric acid (UUA. LPD significantly decreased SUA, UAE, and blood glucose, yet left SCr, UCr, and UUN unchanged. A stepwise regression showed that high UUA is an independent risk factor for DN. LPD remarkably ameliorated degrees of enlarged glomeruli, proliferated mesangial cells, and hyaline-degenerated tubular epithelial cells in diabetic rats. Expression of TNF-α in tubulointerstitium significantly decreased in LPD-fed diabetic rats. Conclusion. LPD inhibits endogenous uric acid synthesis and might accordingly attenuate renal damage in STZ-induced diabetic rats.

Amelioration of both early and late radiation-induced damage to pig skin by essential fatty acids

International Nuclear Information System (INIS)

Hopewell, J.W.; Van den Aardweg, G.J.M.J.; Morris, G.M.

1994-01-01

To evaluate the possible role of essential fatty acids, specifically gamma-linolenic and eicosapentaenoic acid, in the amelioration of early and late radiation damage to the skin. Skin sites on the flank of 22-25 kg female large white pigs were irradiated with either single or fractionated doses (20 F/28 days) of β-rays from 22.5 mm diameter 90 Sr/ 90 Y plaques at a dose rate of ∼3 Gy/min. Essential fatty acids were administered orally in the form of two open-quotes activeclose quotes oils, So-1100 and So-5407, which contained gamma-linolenic acid and a mixture of that oil with eicosapentaenoic acid, respectively. Oils (1.5-6.0 ml) were given daily for 4 weeks prior, both 4 weeks prior and 10-16 weeks after, or in the case of one single dose study, just for 10 weeks after irradiation. Control animals received a open-quotes placeboclose quotes oil, So-1129, containing no gamma linolenic acid or eicosapentaenoic acid over similar time scales before and after irradiation. Acute and late skin reactions were assessed visually and the dose-related incidence of a specific reaction used to compare the effects of different treatment schedules. A reduction in the severity of both the early and late radiation reactions in the skin was only observed when open-quotes activeclose quotes oils were given over the time course of the expression of radiation damage. Prior treatment with oils did not modify the radiation reaction. A 3.0 ml daily dose of either So-1100 or So-5407 given prior to, but also after irradiation with single and fractionated doses of β-rays produced the most significant modification to the radiation reactions, effects consistent with dose modification factors between 1.06-1.24 for the acute reactions of bright red erythema and/or moist desquamation, and of 1.14-1.35 for the late reactions of dusky/mauve erythema and dermal necrosis. 38 refs., 5 tabs

Is Branched-Chain Amino Acids Supplementation an Efficient Nutritional Strategy to Alleviate Skeletal Muscle Damage? A Systematic Review

Directory of Open Access Journals (Sweden)

Alexandre Fouré

2017-09-01

Full Text Available Amino acids and more precisely, branched-chain amino acids (BCAAs, are usually consumed as nutritional supplements by many athletes and people involved in regular and moderate physical activities regardless of their practice level. BCAAs have been initially shown to increase muscle mass and have also been implicated in the limitation of structural and metabolic alterations associated with exercise damage. This systematic review provides a comprehensive analysis of the literature regarding the beneficial effects of BCAAs supplementation within the context of exercise-induced muscle damage or muscle injury. The potential benefit of a BCAAs supplementation was also analyzed according to the supplementation strategy—amount of BCAAs, frequency and duration of the supplementation—and the extent of muscle damage. The review protocol was registered prospectively with Prospective Register for Systematic Reviews (registration number CRD42017073006 and followed Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Literature search was performed from the date of commencement until August 2017 using four online databases (Medline, Cochrane library, Web of science and ScienceDirect. Original research articles: (i written in English; (ii describing experiments performed in Humans who received at least one oral BCAAs supplementation composed of leucine, isoleucine and valine mixture only as a nutritional strategy and (iii reporting a follow-up of at least one day after exercise-induced muscle damage, were included in the systematic review analysis. Quality assessment was undertaken independently using the Quality Criteria Checklist for Primary Research. Changes in indirect markers of muscle damage were considered as primary outcome measures. Secondary outcome measures were the extent of change in indirect markers of muscle damage. In total, 11 studies were included in the analysis. A high heterogeneity was found regarding the

Changes in LDL fatty acid composition as a response to olive oil treatment are inversely related to lipid oxidative damage: The EUROLIVE study

DEFF Research Database (Denmark)

Cicero, Arrigo F G; Nascetti, Simona; López-Sabater, Maria C

2008-01-01

The aim of our study was to assess the changes in the fatty acid composition of low density lipoproteins (LDL) after sustained consumption of olive oil at real-life doses (25 mL/day) and their relationship with lipid oxidative damage.......The aim of our study was to assess the changes in the fatty acid composition of low density lipoproteins (LDL) after sustained consumption of olive oil at real-life doses (25 mL/day) and their relationship with lipid oxidative damage....

Prostacyclin production in rabbit arteries in situ: inhibition by arachidonic acid-induced endothelial cell damage or by low-dose aspirin.

Science.gov (United States)

Ingerman-Wojenski, C; Silver, M J; Smith, J B; Nissenbaum, M; Sedar, A W

1981-04-01

The central artery of the rabbit ear was perfused in situ and effluent fractions from the artery were assayed for 6-keto-prostaglandin F1 alpha (6-K-PGF1 alpha) and thromboxane B2 (TxB2), the stable metabolites of prostacyclin (PGI2) and TxA2, using specific radioimmunoassays. These metabolites of arachidonic acid (AA) were not detected in the effluent during infusion of Tyrode's solution but both metabolites were detected when small amounts of AA were infused into the artery. Examination of the arteries by scanning electron microscopy revealed that high concentrations of AA which caused a short burst of 6-K-PGF1 alpha and TxB2 production damaged the endothelial cells while lower concentrations which stimulated continuous production did not cause damage. When a non-damaging concentration of AA was infused into an artery that had previously received a damaging concentration, PG production was greatly reduced. Pretreatment of the rabbits with 4 mg/kg acetyl-salicylic acid (ASA) inhibited 6-K-PGF1 alpha production by the rabbit ear artery in response to AA and 70% inhibition was still evident 18 hours after ASA.

Spore membrane(s) as the site of damage within heated Clostridium perfringens spores.

Science.gov (United States)

Flowers, R S; Adams, D M

1976-02-01

Clostridium perfringens spores were injured by ultrahigh-temperature treatment at 105 C for 5 min. Injury was manifested as an increased sensitivity to polymyxin and neomycin. Since many of the survivors could not germinate normally the ultrahigh-temperature-treated spores were sensitized to and germinated by lysozyme. Polymyxin reportedly acts upon the cell membrane. Neomycin may inhibit protein synthesis and has surface-active properties. Injured spores were increasingly sensitive to known surface-active agents, sodium lauryl sulfate, sodium deoxycholate, and Roccal, a quaternary ammonium compound. Injured spores sensitive to polymyxin and neomycin also were osmotically fragile and died during outgrowth in a liquid medium unless the medium was supplemented with 20% sucrose, 10% dextran, or 10% polyvinylpyrrolidone. The results suggested that a spore structure destined to become cell membrane or cell wall was the site of injury. Repair of injury during outgrowth in the presence of protein, deoxyribonucleic acid, ribonucleic acid and cell wall synthesis inhibitors was consistent with this hypothesis.

The omega-3 fatty acid, eicosapentaenoic acid (EPA, prevents the damaging effects of tumour necrosis factor (TNF-alpha during murine skeletal muscle cell differentiation

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Pearson Stephen

2008-07-01

Full Text Available Abstract Background Eicosapentaenoic acid (EPA is a ώ-3 polyunsaturated fatty acid with anti-inflammatory and anti-cachetic properties that may have potential benefits with regards to skeletal muscle atrophy conditions where inflammation is present. It is also reported that pathologic levels of the pro-inflammatory cytokine tumour necrosis factor (TNF-α are associated with muscle wasting, exerted through inhibition of myogenic differentiation and enhanced apoptosis. These findings led us to hypothesize that EPA may have a protective effect against skeletal muscle damage induced by the actions of TNF-α. Results The deleterious effects of TNF-α on C2C12 myogenesis were completely inhibited by co-treatment with EPA. Thus, EPA prevented the TNF-mediated loss of MyHC expression and significantly increased myogenic fusion (p p p p p p Conclusion In conclusion, EPA has a protective action against the damaging effects of TNF-α on C2C12 myogenesis. These findings support further investigations of EPA as a potential therapeutic agent during skeletal muscle regeneration following injury.

Alkali production associated with malolactic fermentation by oral streptococci and protection against acid, oxidative, or starvation damage.

Science.gov (United States)

Sheng, Jiangyun; Baldeck, Jeremiah D; Nguyen, Phuong T M; Quivey, Robert G; Marquis, Robert E

2010-07-01

Alkali production by oral streptococci is considered important for dental plaque ecology and caries moderation. Recently, malolactic fermentation (MLF) was identified as a major system for alkali production by oral streptococci, including Streptococcus mutans. Our major objectives in the work described in this paper were to further define the physiology and genetics of MLF of oral streptococci and its roles in protection against metabolic stress damage. L-Malic acid was rapidly fermented to L-lactic acid and CO(2) by induced cells of wild-type S. mutans, but not by deletion mutants for mleS (malolactic enzyme) or mleP (malate permease). Mutants for mleR (the contiguous regulator gene) had intermediate capacities for MLF. Loss of capacity to catalyze MLF resulted in loss of capacity for protection against lethal acidification. MLF was also found to be protective against oxidative and starvation damage. The capacity of S. mutans to produce alkali from malate was greater than its capacity to produce acid from glycolysis at low pH values of 4 or 5. MLF acted additively with the arginine deiminase system for alkali production by Streptococcus sanguinis, but not with urease of Streptococcus salivarius. Malolactic fermentation is clearly a major process for alkali generation by oral streptococci and for protection against environmental stresses.

Alkali production associated with malolactic fermentation by oral streptococci and protection against acid, oxidative, or starvation damage

Science.gov (United States)

Sheng, Jiangyun; Baldeck, Jeremiah D.; Nguyen, Phuong T.M.; Quivey, Robert G.; Marquis, Robert E.

2011-01-01

Alkali production by oral streptococci is considered important for dental plaque ecology and caries moderation. Recently, malolactic fermentation (MLF) was identified as a major system for alkali production by oral streptococci, including Streptococcus mutans. Our major objectives in the work described in this paper were to further define the physiology and genetics of MLF of oral streptococci and its roles in protection against metabolic stress damage. l-Malic acid was rapidly fermented to l-lactic acid and CO2 by induced cells of wild-type S. mutans, but not by deletion mutants for mleS (malolactic enzyme) or mleP (malate permease). Mutants for mleR (the contiguous regulator gene) had intermediate capacities for MLF. Loss of capacity to catalyze MLF resulted in loss of capacity for protection against lethal acidification. MLF was also found to be protective against oxidative and starvation damage. The capacity of S. mutans to produce alkali from malate was greater than its capacity to produce acid from glycolysis at low pH values of 4 or 5. MLF acted additively with the arginine deiminase system for alkali production by Streptococcus sanguinis, but not with urease of Streptococcus salivarius. Malolactic fermentation is clearly a major process for alkali generation by oral streptococci and for protection against environmental stresses. PMID:20651853

No effect of short-term amino acid supplementation on variables related to skeletal muscle damage in 100 km ultra-runners - a randomized controlled trial

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Rosemann Thomas

2011-04-01

Full Text Available Abstract Background The purpose of this study was to investigate the effect of short-term supplementation of amino acids before and during a 100 km ultra-marathon on variables of skeletal muscle damage and muscle soreness. We hypothesized that the supplementation of amino acids before and during an ultra-marathon would lead to a reduction in the variables of skeletal muscle damage, a decrease in muscle soreness and an improved performance. Methods Twenty-eight experienced male ultra-runners were divided into two groups, one with amino acid supplementation and the other as a control group. The amino acid group was supplemented a total of 52.5 g of an amino acid concentrate before and during the 100 km ultra-marathon. Pre- and post-race, creatine kinase, urea and myoglobin were determined. At the same time, the athletes were asked for subjective feelings of muscle soreness. Results Race time was not different between the groups when controlled for personal best time in a 100 km ultra-marathon. The increases in creatine kinase, urea and myoglobin were not different in both groups. Subjective feelings of skeletal muscle soreness were not different between the groups. Conclusions We concluded that short-term supplementation of amino acids before and during a 100 km ultra-marathon had no effect on variables of skeletal muscle damage and muscle soreness.

Damage of guinea pig heart and arteries by a trioleate-enriched diet and of cultured cardiomyocytes by oleic acid.

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Josef Krieglstein

2010-03-01

Full Text Available Mono-unsaturated fatty acids (MUFAs like oleic acid have been shown to cause apoptosis of cultured endothelial cells by activating protein phosphatase type 2C alpha and beta (PP2C. The question arises whether damage of endothelial or other cells could be observed in intact animals fed with a trioleate-enriched diet.Dunkin-Hartley guinea pigs were fed with a trioleate-enriched diet for 5 months. Advanced atherosclerotic changes of the aorta and the coronary arteries could not be seen but the arteries appeared in a pre-atherosclerotic stage of vascular remodelling. However, the weight and size of the hearts were lower than in controls and the number of apoptotic myocytes increased in the hearts of trioleate-fed animals. To confirm the idea that oleic acid may have caused this apoptosis by activation of PP2C, cultured cardiomyocytes from guinea pigs and mice were treated with various lipids. It was demonstrable that oleic acid dose-dependently caused apoptosis of cardiomyocytes from both species, yet, similar to previous experiments with cultured neurons and endothelial cells, stearic acid, elaidic acid and oleic acid methylester did not. The apoptotic effect caused by oleic acid was diminished when PP2C alpha and beta were downregulated by siRNA showing that PP2C was causally involved in apoptosis caused by oleic acid.The glycerol trioleate diet given to guinea pigs for 5 months did not cause marked atherosclerosis but clearly damaged the hearts by activating PP2C alpha and beta. The diet used with 24% (wt/wt glycerol trioleate is not comparable to human diets. The detrimental role of MUFAs for guinea pig heart tissue in vivo is shown for the first time. Whether it is true for humans remains to be shown.

Isolation of deoxyribonucleic acids (A Review)

International Nuclear Information System (INIS)

Garcia Pineda, M. de

1974-01-01

The criteria of choice in this Review have been to gather some of the last advances in the methodology of DNAs isolation; also the description of the generally accepted procedures has been emphasized. Only papers published before March 1974 are reviewed, because this work has been finished during this month. (Author) 109 refs

The deoxyribonucleic acid of Micrococcus radiodurans

Science.gov (United States)

Schein, Arnold H.

1966-01-01

The DNA of Micrococcus radiodurans was prepared by three methods. Although the recovery of DNA varied considerably, the percentage molar base ratios of the DNA from the three preparations were essentially the same: guanine, 33±2; adenine, 18±1; cytosine, 33±2; thymine, 17±1. Base compositions calculated from Tm values and from density in caesium chloride gradients also yielded guanine+cytosine contents of 66 and 68% of total bases respectively. No unusual bases were observed. The S20,w values were characteristic of high-molecular-weight DNA. Electron microscopy showed the purified DNA in long strands; occasionally these were coiled. Images(a)(b)(c)(d)(e)Fig. 1. PMID:16742439

Evaluation of the metabolic fate of munitions material (TNT & RDX) in plant systems and initial assessment of material interaction with plant genetic material (DNA). Initial assessment of plant DNA adducts as biomarkers

Energy Technology Data Exchange (ETDEWEB)

Harvey, S.D.; Clauss, T.W.; Fellows, R.J.; Cataldo, D.A.

1995-08-01

Genetic damage to deoxyribonucleic acid (DNA) has long been suspected of being a fundamental event leading to cancer. A variety of causal factors can result in DNA damage including photodimerization of base pairs, ionizing radiation, specific reaction of DNA with environmental pollutants, and nonspecific oxidative damage caused by the action of highly reactive oxidizing agents produced by metabolism. Because organisms depend on an unadulterated DNA template for reproduction, DNA repair mechanisms are an important defense for maintaining genomic integrity. The objective of this exploratory project was to evaluate the potential for TNT to form DNA adducts in plants. These adducts, if they exist in sufficient quantities, could be potential biomarkers of munitions exposure. The ultimate goal is to develop a simple analytical assay for the determination of blomarkers that is indicative of munitions contamination. DNA repair exists in dynamic equilibrium with DNA damage. Repair mechanisms are capable of keeping DNA damage at remarkably low concentrations provided that the repair capacity is not overwhelmed.

Inhibitors of acid secretion can benefit gastric wound repair independent of luminal pH effects on the site of damage

Science.gov (United States)

Demitrack, Elise S; Aihara, Eitaro; Kenny, Susan; Varro, Andrea; Montrose, Marshall H

2012-01-01

Background and aims The authors’ goal was to measure pH at the gastric surface (pHo) to understand how acid secretion affects the repair of microscopic injury to the gastric epithelium. Methods Microscopic gastric damage was induced by laser light, during confocal/two-photon imaging of pH-sensitive dyes (Cl-NERF, BCECF) that were superfused over the mucosal surface of the exposed gastric corpus of anaesthetised mice. The progression of repair was measured in parallel with pHo. Experimental conditions included varying pH of luminal superfusates, and using omeprazole (60 mg/kg ip) or famotidine (30 mg/kg ip) to inhibit acid secretion. Results Similar rates of epithelial repair and resting pHo values (~pH 4) were reported in the presence of luminal pH 3 or pH 5. Epithelial repair was unreliable at luminal pH 2 and pHo was lower (2.5±0.2, P pH 3). Epithelial repair was slower at luminal pH 7 and pHo was higher (6.4±0.1, PpH 3 or pH 7, omeprazole reduced maximal damage size and accelerated epithelial repair, although only at pH 3 did omeprazole further increase surface pH above the level caused by imposed damage. At luminal pH 7, famotidine also reduced maximal damage size and accelerated epithelial repair. Neither famotidine nor omeprazole raised plasma gastrin levels during the time course of the experiments. Conclusions Epithelial repair in vivo is affected by luminal pH variation, but the beneficial effects of acutely blocking acid secretion extend beyond simply raising luminal and/or surface pH. PMID:21997560

Protective effects of rosmarinic acid on sepsis-induced DNA damage in the liver of Wistar albino rats

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Hatice Gul Goktas

2015-06-01

Full Text Available Sepsis is an imbalance between pro and anti-inflammatory responses. Sepsis induced multiple organ failure that is associated with mortality is characterized by liver, renal, cardiovascular and pulmonary dysfunction and reactive oxygen species (ROS are believed to be involved in the development of sepsis. Plant polyphenols may act as antioxidants by different mechanisms such as free radical scavenging, metal chelation and protein binding. Data indicates possible beneficial effects of plant derived phenolic compounds against sepsis. Rosmarinic acid (RA (α-O-caffeoyl-3,4-dihydroxyphenyllactic acid is a phenolic compound commonly found in various plants such as Rosmarinus officinalis (rosemary, Origanum vulgare (oregano, Thymus vulgaris (thyme, Mentha spicata (spearmint, Perilla frutescens (perilla, Ocimum basilicum (sweet basil and several other medicinal plants. It has been shown that RA has many biological activities including antioxidant, anti-inflammatory, antiallergic, anticancer and actimicrobial and is widely used in cosmetic and food industry. In the present study, we aimed to determine the protective effects of RA against the oxidative DNA damage induced by sepsis in Wistar albino rats. The rats were divided into four groups; sham, sepsis induced, RA-treated, RA treated and sepsis induced groups. Wistar rats were subjected to sepsis by cecal ligation puncture. The liver tissues were carefully dissected from their attachments and totally excised. The concentrations of the hepatic tissue cells were adjusted to approximately 2 x 106 cells/ml. Standard and formamidopyrimidine-DNA glycosylase (Fpg modified comet assay described by Singh et al were used. There were no statistically significant differences in terms of tail length, tail intensity and tail moment between the sham group and the RA-treated groups (p>0.05. The DNA damage was found significantly higher in the sepsis-induced group compared to the sham group (p0.05, and the DNA damage

Quantitative assessment of the ion-beam irradiation induced direct damage of nucleic acid bases through FTIR spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Huang, Qing, E-mail: huangq@ipp.ac.cn [Key Laboratory of Ion Beam Bio-engineering, Institute of Technical Biology and Agriculture Engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences (China); University of Science and Technology of China, Hefei 230029, Anhui (China); Su, Xi; Yao, Guohua; Lu, Yilin; Ke, Zhigang; Liu, Jinghua; Wu, Yuejin; Yu, Zengliang [Key Laboratory of Ion Beam Bio-engineering, Institute of Technical Biology and Agriculture Engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences (China)

2014-07-01

Energetic particles exist ubiquitously in nature, and when they hit DNA molecules in organisms, they may induce critical biological effects such as mutation. It is however still a challenge to measure directly and quantitatively the damage imposed by the energetic ions on target DNA molecules. In this work we attempted to employ Fourier transformation infrared (FTIR) spectroscopy to assess the ion-induced direct damage of four nucleic acid bases, namely, thymine (T), cytosine (C), guanine (G), and adenine (A), which are the building blocks of DNA molecules. The samples were prepared as thin films, irradiated by argon ion-beams at raised ion fluences, and in the meantime measured by FTIR spectroscopy for the damage in a quasi-in-situ manner. It was found that the low-energy ion-beam induced radiosensitivity of the four bases shows the sequence G > T > C > A, wherein the possible mechanism was also discussed.

Prevention of iron- and copper-mediated DNA damage by catecholamine and amino acid neurotransmitters, L-DOPA, and curcumin: metal binding as a general antioxidant mechanism.

Science.gov (United States)

García, Carla R; Angelé-Martínez, Carlos; Wilkes, Jenna A; Wang, Hsiao C; Battin, Erin E; Brumaghim, Julia L

2012-06-07

Concentrations of labile iron and copper are elevated in patients with neurological disorders, causing interest in metal-neurotransmitter interactions. Catecholamine (dopamine, epinephrine, and norepinephrine) and amino acid (glycine, glutamate, and 4-aminobutyrate) neurotransmitters are antioxidants also known to bind metal ions. To investigate the role of metal binding as an antioxidant mechanism for these neurotransmitters, L-dihydroxyphenylalanine (L-DOPA), and curcumin, their abilities to prevent iron- and copper-mediated DNA damage were quantified, cyclic voltammetry was used to determine the relationship between their redox potentials and DNA damage prevention, and UV-vis studies were conducted to determine iron and copper binding as well as iron oxidation rates. In contrast to amino acid neurotransmitters, catecholamine neurotransmitters, L-DOPA, and curcumin prevent significant iron-mediated DNA damage (IC(50) values of 3.2 to 18 μM) and are electrochemically active. However, glycine and glutamate are more effective at preventing copper-mediated DNA damage (IC(50) values of 35 and 12.9 μM, respectively) than L-DOPA, the only catecholamine to prevent this damage (IC(50) = 73 μM). This metal-mediated DNA damage prevention is directly related to the metal-binding behaviour of these compounds. When bound to iron or copper, the catecholamines, amino acids, and curcumin significantly shift iron oxidation potentials and stabilize Fe(3+) over Fe(2+) and Cu(2+) over Cu(+), a factor that may prevent metal redox cycling in vivo. These results highlight the disparate antioxidant activities of neurotransmitters, drugs, and supplements and highlight the importance of considering metal binding when identifying antioxidants to treat and prevent neurodegenerative disorders.

Role of salicylic acid in alleviating oxidative damage in rice roots (Oryza sativa) subjected to cadmium stress

International Nuclear Information System (INIS)

Guo, B.; Liang, Y.C.; Zhu, Y.G.; Zhao, F.J.

2007-01-01

Time-dependent changes in enzymatic and non-enzymatic antioxidants, and lipid peroxidation were investigated in roots of rice (Oryza sativa) grown hydroponically with Cd, with or without pretreatment of salicylic acid (SA). Exposure to 50 μM Cd significantly decreased root growth, and activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), but increased the concentrations of H 2 O 2 , malondialdehyde (MDA), ascorbic acid (AsA), glutathione (GSH) and non-protein thiols (NPT). However, pretreatment with 10 μM SA enhanced the activities of antioxidant enzymes and the concentrations of non-enzymatic antioxidants, but lowered the concentrations of H 2 O 2 and MDA in the Cd-stressed rice compared with the Cd treatment alone. Pretreatment with SA alleviated the Cd-induced inhibition of root growth. The results showed that pretreatment with SA enhanced the antioxidant defense activities in Cd-stressed rice, thus alleviating Cd-induced oxidative damage and enhancing Cd tolerance. The possible mechanism of SA-induced H 2 O 2 signaling in mediating Cd tolerance was discussed. - Pretreatment with SA enhanced the antioxidant defense activities in Cd-stressed rice, thus alleviating Cd-induced oxidative damage and enhancing Cd tolerance

Folic acid and safflower oil supplementation interacts and protects embryos from maternal diabetes-induced damage.

Science.gov (United States)

Higa, R; Kurtz, M; Mazzucco, M B; Musikant, D; White, V; Jawerbaum, A

2012-05-01

Maternal diabetes increases the risk of embryo malformations. Folic acid and safflower oil supplementations have been shown to reduce embryo malformations in experimental models of diabetes. In this study we here tested whether folic acid and safflower oil supplementations interact to prevent embryo malformations in diabetic rats, and analyzed whether they act through the regulation of matrix metalloproteinases (MMPs), their endogenous inhibitors (TIMPs), and nitric oxide (NO) and reactive oxygen species production. Diabetes was induced by streptozotocin administration prior to mating. From Day 0.5 of pregnancy, rats did or did not receive folic acid (15 mg/kg) and/or a 6% safflower oil-supplemented diet. Embryos and decidua were explanted on Day 10.5 of gestation for further analysis of embryo resorptions and malformations, MMP-2 and MMP-9 activities, TIMP-1 and TIMP-2 levels, NO production and lipid peroxidation. Maternal diabetes induced resorptions and malformations that were prevented by folic acid and safflower oil supplementation. MMP-2 and MMP-9 activities were increased in embryos and decidua from diabetic rats and decreased with safflower oil and folic acid supplementations. In diabetic animals, the embryonic and decidual TIMPs were increased mainly with safflower oil supplementation in decidua and with folic acid in embryos. NO overproduction was decreased in decidua from diabetic rats treated with folic acid alone and in combination with safflower oil. These treatments also prevented increases in embryonic and decidual lipid peroxidation. In conclusion, folic acid and safflower oil supplementations interact and protect the embryos from diabetes-induced damage through several pathways related to a decrease in pro-inflammatory mediators.

Zurampic Protects Pancreatic β-Cells from High Uric Acid Induced-Damage by Inhibiting URAT1 and Inactivating the ROS/AMPK/ERK Pathways

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Ying Xin

2018-05-01

Full Text Available Background/Aims: Zurampic is a US FDA approved drug for treatment of gout. However, the influence of Zurampic on pancreatic β-cells remains unclear. The study aimed to evaluate the effects of Zurampic on high uric acid-induced damage of pancreatic β-cells and the possible underlying mechanisms. Methods: INS-1 cells and primary rat islets were stimulated with Zurampic and the mRNA expression of urate transporter 1 (URAT1 was assessed by qRT-PCR. Cells were stimulated with uric acid or uric acid plus Zurampic, and cell viability, apoptosis and ROS release were measured by MTT and flow cytometry assays. Western blot analysis was performed to evaluate the expressions of active Caspase-3 and phosphorylation of AMPK and ERK. Finally, cells were stimulated with uric acid or uric acid plus Zurampic at low/high level of glucose (2.8/16.7 mM glucose, and the insulin release was assessed by ELISA. Results: mRNA expression of URAT1 was decreased by Zurampic in a dose-dependent manner. Uric acid decreased cell viability, promoted cell apoptosis and induced ROS release. Uric acid-induced alterations could be reversed by Zurampic. Activation of Caspase-3 and phosphorylation of AMPK and ERK were enhanced by uric acid, and the enhancements were reversed by Zurampic. Decreased phosphorylation of AMPK and ERK, induced by Zurampic, was further reduced by adding inhibitor of AMPK or ERK. Besides, uric acid inhibited high glucose-induced insulin secretion and the inhibition was rescued by Zurampic. Conclusions: Zurampic has a protective effect on pancreatic β-cells against uric acid induced-damage by inhibiting URAT1 and inactivating the ROS/AMPK/ERK pathway.

Inflammation but no DNA (deoxyribonucleic acid) damage in mice exposed to airborne dust from a biofuel plant

DEFF Research Database (Denmark)

Madsen, Anne Mette; Saber, Anne Thoustrup; Nordly, Pernille

2008-01-01

Objectives Particles in ambient air are associated with such health effects as lung diseases and cancer of the lung. Exposure to bioaerosols has been found to be associated with respiratory symptoms. The toxic properties of exposure to combustion and bioaerosol particles from biofuel plants have ...

Biologically relevant oxidants and terminology, classification and nomenclature of oxidatively generated damage to nucleobases and 2-deoxyribose in nucleic acids

DEFF Research Database (Denmark)

Cadet, Jean; Loft, Steffen; Olinski, Ryszard

2012-01-01

A broad scientific community is involved in investigations aimed at delineating the mechanisms of formation and cellular processing of oxidatively generated damage to nucleic acids. Perhaps as a consequence of this breadth of research expertise, there are nomenclature problems for several of the ...

Protective effects of folic acid on DNA damage and DNA methylation levels induced by N-methyl- N'-nitro- N-nitrosoguanidine in Kazakh esophageal epithelial cells.

Science.gov (United States)

Chen, Y; Feng, H; Chen, D; Abuduwaili, K; Li, X; Zhang, H

2018-01-01

The protective effects of folic acid on DNA damage and DNA methylation induced by N-methyl- N'-nitro- N-nitrosoguanidine (MNNG) in Kazakh esophageal epithelial cells were investigated using a 3 × 3 factorial design trial. The cells were cultured in vitro and exposed to media containing different concentrations of folic acid and MNNG, after which growth indices were detected. DNA damage levels were measured using comet assays, and genome-wide DNA methylation levels (MLs) were measured using high-performance liquid chromatography. The DNA methylation of methylenetetrahydrofolate reductase (MTHFR) and folate receptor- α (FR α) genes was detected by bisulfite sequencing polymerase chain reaction (PCR). The results showed significant increases in tail DNA concentration, tail length, and Olive tail moment ( p methylation frequencies of MTHFR and FR α genes. In particular, significant differences were observed in the promoter regions of both genes ( p methylation in Kazakh esophageal epithelial cells upon MNNG exposure. Thus, sufficient folic acid levels could play a protective role against the damage induced by this compound.

Pristanic acid provokes lipid, protein, and DNA oxidative damage and reduces the antioxidant defenses in cerebellum of young rats.

Science.gov (United States)

Busanello, Estela Natacha Brandt; Lobato, Vannessa Gonçalves Araujo; Zanatta, Ângela; Borges, Clarissa Günther; Tonin, Anelise Miotti; Viegas, Carolina Maso; Manfredini, Vanusa; Ribeiro, César Augusto João; Vargas, Carmen Regla; de Souza, Diogo Onofre Gomes; Wajner, Moacir

2014-12-01

Zellweger syndrome (ZS) and some peroxisomal diseases are severe inherited disorders mainly characterized by neurological symptoms and cerebellum abnormalities, whose pathogenesis is poorly understood. Biochemically, these diseases are mainly characterized by accumulation of pristanic acid (Prist) and other fatty acids in the brain and other tissues. In this work, we evaluated the in vitro influence of Prist on redox homeostasis by measuring lipid, protein, and DNA damage, as well as the antioxidant defenses and the activities of aconitase and α-ketoglutarate dehydrogenase in cerebellum of 30-day-old rats. The effect of Prist on DNA damage was also evaluated in blood of these animals. Some parameters were also evaluated in cerebellum from neonatal rats and in cerebellum neuronal cultures. Prist significantly increased malondialdehyde (MDA) levels and carbonyl formation and reduced sulfhydryl content and glutathione (GSH) concentrations in cerebellum of young rats. It also caused DNA strand damage in cerebellum and induced a high micronuclei frequency in blood. On the other hand, this fatty acid significantly reduced α-ketoglutarate dehydrogenase and aconitase activities in rat cerebellum. We also verified that Prist-induced increase of MDA levels was totally prevented by melatonin and attenuated by α-tocopherol but not by the nitric oxide synthase inhibitor N(ω)-nitro-L-arginine methyl ester, indicating the involvement of reactive oxygen species in this effect. Cerebellum from neonate rats also showed marked alterations of redox homeostasis, including an increase of MDA levels and a decrease of sulfhydryl content and GSH concentrations elicited by Prist. Finally, Prist provoked an increase of dichlorofluorescein (DCFH) oxidation in cerebellum-cultivated neurons. Our present data indicate that Prist compromises redox homeostasis in rat cerebellum and blood and inhibits critical enzymes of the citric acid cycle that are susceptible to free radical attack. The

Direct damage to vegetation caused by acid rain and polluted cloud: definition of critical levels for forest trees.

Science.gov (United States)

Cape, J N

1993-01-01

The concept of critical levels was developed in order to define short-term and long-term average concentrations of gaseous pollutants above which plants may be damaged. Although the usual way in which pollutants in precipitation (wet deposition) influence vegetation is by affecting soil processes, plant foliage exposed to fog and cloud, which often contain much greater concentrations of pollutant ions than rain, may be damaged directly. The idea of a critical level has been extended to define concentrations of pollutants in wet deposition above which direct damage to plants is likely. Concentrations of acidity and sulphate measured in mountain and coastal cloud are summarised. Vegetation at risk of injury is identified as montane forest growing close to the cloud base, where ion concentrations are highest. The direct effects of acidic precipitation on trees are reviewed, based on experimental exposure of plants to simulated acidic rain, fog or mist. Although most experiments have reported results in terms of pH (H(+) concentration), the accompanying anion is important, with sulphate being more damaging than nitrate. Both conifers and broadleaved tree seedlings showing subtle changes in the structural characteristics of leaf surfaces after exposure to mist or rain at or about pH 3.5, or sulphate concentration of 150 micromol litre(-1). Visible lesions on leaf surfaces occur at around pH 3 (500 micromol litre(-1) sulphate), broadleaved species tending to be more sensitive than conifers. Effects on photosynthesis and water relations, and interactions with other stresses (e.g. frost), have usually been observed only for treatments which have also caused visible injury to the leaf surface. Few experiments on the direct effects of polluted cloud have been conducted under field conditions with mature trees, which unlike seedlings in controlled conditions, may suffer a growth reduction in the absence of visible injury. Although leaching of cations (Ca(2+), Mg(2+), K(+)) is

Radiation damage to nucleoprotein complexes in macromolecular crystallography

International Nuclear Information System (INIS)

Bury, Charles; Garman, Elspeth F.; Ginn, Helen Mary; Ravelli, Raimond B. G.; Carmichael, Ian; Kneale, Geoff; McGeehan, John E.

2015-01-01

Quantitative X-ray induced radiation damage studies employing a model protein–DNA complex revealed a striking partition of damage sites. The DNA component was observed to be far more resistant to specific damage compared with the protein. Significant progress has been made in macromolecular crystallography over recent years in both the understanding and mitigation of X-ray induced radiation damage when collecting diffraction data from crystalline proteins. In contrast, despite the large field that is productively engaged in the study of radiation chemistry of nucleic acids, particularly of DNA, there are currently very few X-ray crystallographic studies on radiation damage mechanisms in nucleic acids. Quantitative comparison of damage to protein and DNA crystals separately is challenging, but many of the issues are circumvented by studying pre-formed biological nucleoprotein complexes where direct comparison of each component can be made under the same controlled conditions. Here a model protein–DNA complex C.Esp1396I is employed to investigate specific damage mechanisms for protein and DNA in a biologically relevant complex over a large dose range (2.07–44.63 MGy). In order to allow a quantitative analysis of radiation damage sites from a complex series of macromolecular diffraction data, a computational method has been developed that is generally applicable to the field. Typical specific damage was observed for both the protein on particular amino acids and for the DNA on, for example, the cleavage of base-sugar N 1 —C and sugar-phosphate C—O bonds. Strikingly the DNA component was determined to be far more resistant to specific damage than the protein for the investigated dose range. At low doses the protein was observed to be susceptible to radiation damage while the DNA was far more resistant, damage only being observed at significantly higher doses

Lactation Affects Isolated Mitochondria and Its Fatty Acid Composition but Has No Effect on Tissue Protein Oxidation, Lipid Peroxidation or DNA-Damage in Laboratory Mice

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Teresa G. Valencak

2016-01-01

Full Text Available Linking peak energy metabolism to lifespan and aging remains a major question especially when focusing on lactation in females. We studied, if and how lactation affects in vitro mitochondrial oxygen consumption and mitochondrial fatty acid composition. In addition, we assessed DNA damage, lipid peroxidation and protein carbonyls to extrapolate on oxidative stress in mothers. As model system we used C57BL/6NCrl mice and exposed lactating females to two ambient temperatures (15 °C and 22 °C while they nursed their offspring until weaning. We found that state II and state IV respiration rates of liver mitochondria were significantly higher in the lactating animals than in non-lactating mice. Fatty acid composition of isolated liver and heart mitochondria differed between lactating and non-lactating mice with higher n-6, and lower n-3 polyunsaturated fatty acids in the lactating females. Surprisingly, lactation did not affect protein carbonyls, lipid peroxidation and DNA damage, nor did moderate cold exposure of 15 °C. We conclude that lactation increases rates of mitochondrial uncoupling and alters mitochondrial fatty acid composition thus supporting the “uncoupling to survive” hypothesis. Regarding oxidative stress, we found no impact of lactation and lower ambient temperature and contribute to growing evidence that there is no linear relationship between oxidative damage and lactation.

Modification and restriction of T-even bacteriophages. In vitro degradation of deoxyribonucleic acid containing 5-hydroxymethylctosine.

Science.gov (United States)

Fleischman, R A; Cambell, J L; Richardson, C C

1976-03-25

Using the single-stranded circular DNA of bacteriophage fd as template, double-stranded circular DNA has been prepared in vitro with either 5-hydroxymethylcytosine ([hmdC]DNA) or cytosine ([dC]DNA) in the product strand. Extracts prepared from Escherichia coli cells restrictive to T-even phage containing nonglucosylated DNA degrade [hmdC]DNA to acid-soluble material in vitro, but do not degrade [dC]dna. In contrast, extracts prepared from E. coli K12 rglA- rglB-, a strain permissive to T-even phage containing nonglucosylated DNA, do not degrade [hmdC]DNA or [dC]DNA. In addition, glucosylation of the [hmdC]DNA renders it resistant to degradation by extracts from restrictive strains. The conversion of [hmdC]DNA to acid-soluble material in vitro consists of an HmCyt-specific endonucleolytic cleavage requiring the presence of the RglB gene product to form a linear molecule, followed by a non-HmCyt-specific hydrolysis of the linear DNA to acid-soluble fragments, catalyzed in part by exonuclease V. The RglB protein present in extracts of E. coli K12 rglA- rglB+ has been purified 200-fold by complementation with extracts from E. coli K12 rglA- rglB-. The purified RglB protein does not contain detectable HmCyt-specific endonuclease or exonuclease activity. In vitro endonucleolytic cleavage of [hmdC]DNA thus requires additional factors present in cell extracts.

Rubber acid damage in fire hoses

Energy Technology Data Exchange (ETDEWEB)

Thaysen, A C; Bunker, H J; Adams, M E

1945-03-17

Hose failure observed in rubber-lined fire hoses may be due to sulfuric acid formed from sulfur present in hoses when they are not properly dried. Microorganisms were observed in numerous samples of hose liquid and as a result of the experiments which were carried it was concluded that: the production of rubber acid in hose is due to the activity of sulfur-oxidizing bacteria of the Thiobacterium thiooxidans group. Such acid will invariably be formed when the hoses are stored with the linings wet, when the responsible bacteria are present and when the free sulfur content of the hoses exceeds 0.1 precent. The alternative of preventing the introduction of the causal bacteria does not appear practical since the water used in fire-fighting in the London district is taken from static supplies.

Radiation-induced free radicals in DNA studied by electron paramagnetic resonance

International Nuclear Information System (INIS)

Graeslund, A.

1974-01-01

Radiation biology aims at an understanding of the effects of radiation on biological material. The studied systems may vary in complexity and size from a whole organism to the molecular constituents of a cell. The observed effects are accordingly varied, from visible somatic effects on the organism to physico-chemical molecular changes. Radiation biophysics may be considered as a specialized branch of radiation biology, dealing with physical aspects of radiation damage, particularly at a molecular or sub-cellular level. The work to be presented here is in the field of radiation biophysics, and concerns physical studies of radiation effects on deoxyribonucleic acid, DNA, the hereditary substance of all living organisms. (author)

Structural aspects of catalytic mechanisms of endonucleases and their binding to nucleic acids

Energy Technology Data Exchange (ETDEWEB)

Zhukhlistova, N. E.; Balaev, V. V.; Lyashenko, A. V.; Lashkov, A. A., E-mail: alashkov83@gmail.com [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

2012-05-15

Endonucleases (EC 3.1) are enzymes of the hydrolase class that catalyze the hydrolytic cleavage of deoxyribonucleic and ribonucleic acids at any region of the polynucleotide chain. Endonucleases are widely used both in biotechnological processes and in veterinary medicine as antiviral agents. Medical applications of endonucleases in human cancer therapy hold promise. The results of X-ray diffraction studies of the spatial organization of endonucleases and their complexes and the mechanism of their action are analyzed and generalized. An analysis of the structural studies of this class of enzymes showed that the specific binding of enzymes to nucleic acids is characterized by interactions with nitrogen bases and the nucleotide backbone, whereas the nonspecific binding of enzymes is generally characterized by interactions only with the nucleic-acid backbone. It should be taken into account that the specificity can be modulated by metal ions and certain low-molecular-weight organic compounds. To test the hypotheses about specific and nonspecific nucleic-acid-binding proteins, it is necessary to perform additional studies of atomic-resolution three-dimensional structures of enzyme-nucleic-acid complexes by methods of structural biology.

Self-assembled monolayer based electrochemical nucleic acid sensor for Vibrio cholerae detection

International Nuclear Information System (INIS)

Patel, Manoj K; Solanki, Pratima R; Agrawal, Ved V; Khandelwal, Sachin; Ansari, S G; Malhotra, B D

2012-01-01

Nucleic acid sensor has been fabricated by immobilization of thiolated (5' end) single stranded deoxyribonucleic acid probe (ssDNA-SH) onto gold (Au) coated glass electrode for Vibriocholerae detection. This ssDNA-SH/Au bioelectrode characterized using atomic force microscopy (AFM),Fourier transforms infrared spectroscopy (FT-IR) and electrochemical technique, has been used for hybridization detection of genomic DNA (dsDNA/Au). This ssDNA-SH/Au bioelectrode can specifically detect up to 100- 500 ng/μL genomic DNA of Vibriocholeare within 60 s of hybridization time at 25°C by cyclic voltammetry (CV) using methylene blue (MB) as electro-active DNA hybridization indicator. The value of sensitivity of the dsDNA/Au electrode has been determined as 0.027μA/ng cm −2 with regression coefficient as 0.978. This DNA bioelectrode is stable for about 4 months when stored at 4°C.

Protocol optimization for deoxyribonucleic acid (DNA) extraction ...

African Journals Online (AJOL)

MUNAWAR ROOMI

2013-12-18

Dec 18, 2013 ... research institutes, such as National Agricultural Research Centre. (NARC) .... and was experienced on soybean, chickpea seeds and wheat. When high ... suitable for molecular marker and transgenic analysis. Afr. J.

Protocol optimization for deoxyribonucleic acid (DNA) extraction ...

African Journals Online (AJOL)

Arachis hypogaea L.) is particularly problematic due to the presence of phenolic compounds and polysaccharides. Inconsistencies in extraction results can be attributed to the age and growth stages of the plant material analyzed. Mature leaves ...

Lambda bacteriophage gene products and x-ray sensitivity of Escherichia coli: comparison of red-dependent and gam-dependent radioresistance

International Nuclear Information System (INIS)

Trgovcevic, Z.; Rupp, W.D.

1975-01-01

When gene products of lambda bacteriophage are introduced into a cell by transient induction of a lysogen, increased resistance of the cells to x rays results. This phenomenon has been called phage-induced radioresistance. Genetic studies show at least two classes of induced radioresistance. The first type depends on the products of the lambda red genes and is observed in bacteria that are mutated in the recB gene. It is thought that the lambda red products compensate for the missing RecBC nuclease in the repair of x-ray damage. An optimal effect is obtained even when the lambda red products are supplied 1 h after irradiation. The lesions that are affected by the red-dependent process are probably not deoxyribonucleic acid strand breaks because the extent of deoxyribonucleic acid strand rejoining is not altered by the red products. The second type of phage-induced radioresistance requires the gam product of lambda and is observed in wild-type and polA strains. The lambda gam + gene product must be present immediately after irradiation to exert its full effect. In its presence, DNA breakdown is decreased, and a greater fraction of DNA is converted back to high molecular weight. Strains carrying lex, recA, or certain other combinations of mutations do not show any detectable phage-induced radioresistance. (U.S.)

Plasma membrane damage detected by nucleic acid leakage

International Nuclear Information System (INIS)

Fortunati, E.; Bianchi, V.

1989-01-01

Among the indicators of membrane damage, the leakage of intracellular components into the medium is the most directly related to the perturbations of the membrane molecular organization. The extent of the damage can be evaluated from the size of the released components. We have designed a protocol for the detection of membrane leakage based on the preincubation of cells with tritiated adenine for 24 h, followed by a 24-h chase in nonradioactive medium. The treatment takes place when the distribution of the precursor among its end products has reached the plateau, and thus the differences of radioactivity in the fractions obtained from the control and treated cultures (medium, nucleotide pool, RNA, DNA) correspond to actual quantitative variations induced by the test chemical. Aliquots of the medium are processed to determine which percentage of the released material is macromolecular, in order to distinguish between mild and severe membrane damage. The origin of the extracellular radioactivity can be recognized from the variations of RNA counts in the treated cells. DNA radioactivity is used to evaluate the number of cells that remain attached to the plates in the different conditions of treatment. By this means, generalized permeabilization of membranes to macromolecules is distinguished from complete solubilization of only a subpopulation of cells. We present some examples of application of the protocol with detergents (LAS, SDS, Triton X-100) and with Cr(VI), which damages cell membranes by a different mechanism of action

DNA repair in cancer: emerging targets for personalized therapy

International Nuclear Information System (INIS)

Abbotts, Rachel; Thompson, Nicola; Madhusudan, Srinivasan

2014-01-01

Genomic deoxyribonucleic acid (DNA) is under constant threat from endogenous and exogenous DNA damaging agents. Mammalian cells have evolved highly conserved DNA repair machinery to process DNA damage and maintain genomic integrity. Impaired DNA repair is a major driver for carcinogenesis and could promote aggressive cancer biology. Interestingly, in established tumors, DNA repair activity is required to counteract oxidative DNA damage that is prevalent in the tumor microenvironment. Emerging clinical data provide compelling evidence that overexpression of DNA repair factors may have prognostic and predictive significance in patients. More recently, DNA repair inhibition has emerged as a promising target for anticancer therapy. Synthetic lethality exploits intergene relationships where the loss of function of either of two related genes is nonlethal, but loss of both causes cell death. Exploiting this approach by targeting DNA repair has emerged as a promising strategy for personalized cancer therapy. In the current review, we focus on recent advances with a particular focus on synthetic lethality targeting in cancer

Far-red fluorescent probes for canonical and non-canonical nucleic acid structures: current progress and future implications.

Science.gov (United States)

Suseela, Y V; Narayanaswamy, Nagarjun; Pratihar, Sumon; Govindaraju, Thimmaiah

2018-02-05

The structural diversity and functional relevance of nucleic acids (NAs), mainly deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are indispensable for almost all living organisms, with minute aberrations in their structure and function becoming causative factors in numerous human diseases. The standard structures of NAs, termed canonical structures, are supported by Watson-Crick hydrogen bonding. Under special physiological conditions, NAs adopt distinct spatial organisations, giving rise to non-canonical conformations supported by hydrogen bonding other than the Watson-Crick type; such non-canonical structures have a definite function in controlling gene expression and are considered as novel diagnostic and therapeutic targets. Development of molecular probes for these canonical and non-canonical DNA/RNA structures has been an active field of research. Among the numerous probes studied, probes with turn-on fluorescence in the far-red (600-750 nm) region are highly sought-after due to minimal autofluorescence and cellular damage. Far-red fluorescent probes are vital for real-time imaging of NAs in live cells as they provide good resolution and minimal perturbation of the cell under investigation. In this review, we present recent advances in the area of far-red fluorescent probes of DNA/RNA and non-canonical G-quadruplex structures. For the sake of continuity and completeness, we provide a brief overview of visible fluorescent probes. Utmost importance is given to design criteria, characteristic properties and biological applications, including in cellulo imaging, apart from critical discussion on limitations of the far-red fluorescent probes. Finally, we offer current and future prospects in targeting canonical and non-canonical NAs specific to cellular organelles, through sequence- and conformation-specific far-red fluorescent probes. We also cover their implications in chemical and molecular biology, with particular focus on decoding various disease

Antiretroviral therapy-induced insulin resistance and oxidative deoxy nucleic acid damage in human immunodeficiency virus-1 patients

Directory of Open Access Journals (Sweden)

Vaishali Kolgiri Honnapurmath

2017-01-01

Full Text Available Background and Objectives: Insulin resistance (IR is frequent in human immunodeficiency virus (HIV infection and may be related to antiretroviral therapy (ART. Increased oxidative stress parameters and carbonyl protein are linked to insulin sensitivity. The present study is aimed to determine IR, its association with oxidative deoxy nucleic acid (DNA damage in HIV-1-infected patients with different ART status. Materials and Methods: In this case–control study, a total 600 subjects were included. We used plasma levels of the oxidized base, 8-hydroxy-2-deoxyguanosine (8-OHdG, as our biomarker of oxidative DNA damage. 8-OHdG was measured with the highly sensitive 8-OHdG check enzyme-linked immunosorbent assay kit. IR was determined using homeostasis model assessment. Results: All subjects were randomly selected and grouped as HIV-negative (control group (n = 300, HIV-positive without ART (n = 100, HIV-positive with ART first line (n = 100, and HIV-positive with ART second line (n = 100. IR and oxidative DNA damage were significantly higher in HIV-positive patients with second-line ART and HIV-positive patients with first-line ART than ART-naive patients. In a linear regression analysis, increased IR was positively associated with the increased DNA damage (odds ratio: 3.052, 95% confidence interval: 2.595–3.509 P < 0.001. Interpretation and Conclusions: In this study, we observed that ART plays a significant role in the development of IR and oxidative DNA damage in HIV-positive patients taking ART. Awareness and knowledge of these biomarkers may prove helpful to clinicians while prescribing ART to HIV/AIDS patients. Larger studies are warranted to determine the exact role of ART in the induction of IR and DNA damage.

Pharmacology of post-irradiation damage of blood capillaries

International Nuclear Information System (INIS)

Pospisil, J.; Pouckova, P.

1979-01-01

Available literature data are summed up on the effect of a number of substances on irradiation damage to blood capillaries. The substances include vitamins, bioflavonoids, serotonine, histamine, bradykinin, ACTH, adrenal hormones, vasopressin, estrogens, prostaglandins, escin 1-butanol, diisopropylfluorophosphate, phenoxybenzamine, 1,4-dihydroxybenzenesulphonic acid derivatives, and xi-aminohexanoic acid. The data include the effects of the substances administered before and after irradiation on blood capillary damage and on mortality. (Ha)

Prevention Effect of Poly-Gamma-Glutamic Acid on Tissue Damage Induced by Gamma Irradiation as a Natural Cross-Linker

Energy Technology Data Exchange (ETDEWEB)

Kim, Jaehun; Sung, Nakyun; Kim, Jeongsoo; Jo, Euri; Choi, Jongil; Park, Jongheum; Lee, Juwoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Kwangwon [Eulji Univ. Hospital, Daejeon (Korea, Republic of); Kwon, Jungkee [Chonbuk National Univ., Jeonju (Korea, Republic of); Kim, Taewoon [Jeonbuk Technopark, Jeonju (Korea, Republic of)

2012-03-15

This study was to determine the prevention effect of poly-gamma-glutamic acid (PGA) on tissue damage induced by gamma irradiation for development of xenograft. PGA (MW 2000 kDa) extracted from permeated soy bean (natto) was used in this study as natural compound, and glutaraldehyde (GA) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) were used as a control, chemical based cross-linking agents. GA, EDC and PGA treated porcine tendons were gamma-irradiated at the dose of 30 kGy. Prevention effects against tissue damage were measured as the result of tensile strength, hydroxyproline contents and tissue morphological analysis. Tensile of porcine tendon was remarkably decreased by gamma irradiation, but increased in PGA treated group. Morphological analysis showed that collagen structure was broken by gamma irradiation, but attenuated by PGA treatment. Base on the results, it demonstrated that gamma irradiation can induce severe alteration of porcine tendon, but PGA can effectively improve the tissue damage.

Prevention Effect of Poly-Gamma-Glutamic Acid on Tissue Damage Induced by Gamma Irradiation as a Natural Cross-Linker

International Nuclear Information System (INIS)

Kim, Jaehun; Sung, Nakyun; Kim, Jeongsoo; Jo, Euri; Choi, Jongil; Park, Jongheum; Lee, Juwoon; Lee, Kwangwon; Kwon, Jungkee; Kim, Taewoon

2012-01-01

This study was to determine the prevention effect of poly-gamma-glutamic acid (PGA) on tissue damage induced by gamma irradiation for development of xenograft. PGA (MW 2000 kDa) extracted from permeated soy bean (natto) was used in this study as natural compound, and glutaraldehyde (GA) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) were used as a control, chemical based cross-linking agents. GA, EDC and PGA treated porcine tendons were gamma-irradiated at the dose of 30 kGy. Prevention effects against tissue damage were measured as the result of tensile strength, hydroxyproline contents and tissue morphological analysis. Tensile of porcine tendon was remarkably decreased by gamma irradiation, but increased in PGA treated group. Morphological analysis showed that collagen structure was broken by gamma irradiation, but attenuated by PGA treatment. Base on the results, it demonstrated that gamma irradiation can induce severe alteration of porcine tendon, but PGA can effectively improve the tissue damage

Growth hormone reverses excitotoxic damage induced by kainic acid in the green iguana neuroretina.

Science.gov (United States)

Ávila-Mendoza, José; Mora, Janeth; Carranza, Martha; Luna, Maricela; Arámburo, Carlos

2016-08-01

It is known that growth hormone (GH) is expressed in extrapituitary tissues, including the nervous system and ocular tissues, where it is involved in autocrine/paracrine actions related to cell survival and anti-apoptosis in several vertebrates. Little is known, however, in reptiles, so we analyzed the expression and distribution of GH in the eye of green iguana and its potential neuroprotective role in retinas that were damaged by the intraocular administration of kainic acid (KA). It was found, by Western blotting, that GH-immunoreactivity (GH-IR) was expressed as two isoforms (15 and 26kDa, under reducing conditions) in cornea, vitreous, retina, crystalline, iris and sclera, in varying proportions. Also, two bands for the growth hormone receptor (GHR)-IR were observed (70 and 44kDa, respectively) in the same tissues. By immunofluorescence, GH-IR was found in neurons present in several layers of the neuroretina (inner nuclear [INL], outer nuclear [ONL] and ganglion cell [GCL] layers) as determined by its co-existence with NeuN, but not in glial cells. In addition, GH and GHR co-expression was found in the same cells, suggesting paracrine/autocrine interactions. KA administration induced retinal excitotoxic damage, as determined by a significant reduction of the cell density and an increase in the appearance of apoptotic cells in the INL and GCL. In response to KA injury, both endogenous GH and Insulin-like Growth Factor I (IGF-I) expression were increased by 70±1.8% and 33.3±16%, respectively. The addition of exogenous GH significantly prevented the retinal damage produced by the loss of cytoarchitecture and cell density in the GCL (from 4.9±0.79 in the control, to 1.45±0.2 with KA, to 6.35±0.49cell/mm(2) with KA+GH) and in the INL (19.12±1.6, 10.05±1.9, 21.0±0.8cell/mm(2), respectively) generated by the long-term effect of 1mM KA intraocular administration. The co-incubation with a specific anti-GH antibody, however, blocked the protective effect of GH

Polypyrrole-polyvinyl sulphonate film based disposable nucleic acid biosensor

Energy Technology Data Exchange (ETDEWEB)

Prabhakar, Nirmal [Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India); Centre for Biomedical Engineering, Indian Institute of Technology, Hauz Khas, New Delhi 110016 (India); Arora, Kavita [Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India); Singh, Surinder P. [Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India); Pandey, Manoj K. [Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India); Singh, Harpal [Centre for Biomedical Engineering, Indian Institute of Technology, Hauz Khas, New Delhi 110016 (India); Malhotra, Bansi D. [Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110012 (India)]. E-mail: bansi.malhotra@gmail.com

2007-04-18

Double stranded calf thymus deoxyribonucleic acid entrapped polypyrrole-polyvinyl sulphonate (dsCT-DNA-PPy-PVS) films fabricated onto indium-tin-oxide (ITO) coated glass plates have been used to detect organophosphates such as chlorpyrifos and malathion. These disposable dsCT-DNA-PPy-PVS/ITO bioelectrodes have been characterized using cyclic voltammetry, Fourier-transform-infra-red (FTIR) spectroscopy and atomic force microscopy (AFM), respectively. These biosensing electrodes have a response time of 30 s, are stable for about 5 months when stored in desiccated conditions at 25 deg. C and can be used to amperometrically detect chlorpyrifos (0.0016-0.025 ppm) and malathion (0.17-5.0), respectively. The additive effect of these pesticides on the amperometric response of the disposable dsCT-DNA-PPy-PVS/ITO bioelectrodes has also been investigated.

Could humic acid relieve the biochemical toxicities and DNA damage caused by nickel and deltamethrin in earthworms (Eisenia foetida)?

Science.gov (United States)

Shen, Chen-Chao; Shen, Dong-Sheng; Shentu, Jia-Li; Wang, Mei-Zhen; Wan, Ming-Yang

2015-12-01

The aim of the study was to determine whether humic acid (HA) prevented gene and biochemical toxic effects in earthworms (Eisenia foetida) exposed to nickel and deltamethrin (at 100 and 1 mg kg(-1), respectively) in soil. Cellular- and molecular-level toxic effects of nickel and deltamethrin in earthworms were evaluated by measuring damage to lipid membranes and DNA and the production of protein carbonyls over 42 days of exposure. Nickel and deltamethrin induced significant levels of oxidative stress in earthworms, increasing the production of peroxidation products (malondialdehyde and protein carbonyls) and increasing the comet assay tail DNA% (determined by single-cell gel electrophoresis). DNA damage was the most sensitive of the three indices because it gave a higher sample/control ratio than did the other indices. The presence of HA alleviated (in decreasing order of effectiveness) damage to DNA, proteins, and lipid membranes caused by nickel and deltamethrin. A low HA dose (0.5-1% HA in soil) prevented a great deal of lipid membrane damage, but the highest HA dose (3% HA in soil) prevented still more DNA damage. However, the malondialdehyde concentrations in earthworms were higher at the highest HA dose than at the lower HA doses. The amounts of protein carbonyls produced at different HA doses were not significantly different. The toxic effects to earthworms caused by increased oxidizable nickel concentrations could be relieved by adding HA.

Different reparability of the chromosomal and cytoplasmic deoxyribonucleic acid in Escherichia coli damaged by γ and ultraviolet irradiation

International Nuclear Information System (INIS)

Petranovic, D.; Petranovic, M.; Nozinic, R.; Trgovcevic, Z.

1978-01-01

The relative efficiencies by which chromosomal and extrachromosomal DNAs are repaired in irradiated bacteria were assayed. Repair-proficient Escherichia coli C600 cells lysogenic for, or infected with, the thermoinducible phage lambdacI857 ind were exposed to γ or uv radiation and then tested for colony- and plaque-forming ability. The results show that the bacterial cell is about 5 times more sensitive to γ rays and about 1.5 times more sensitive to uv light, if compared to either (1) the prophage that is irradiated in the bacterial chromosome and, on heat induction, repaired in the cytoplasm or (2) the infecting phage that is irradiated and repaired in the cytoplasm. Since the bacterial DNA is about 80 times larger than the phage DNA, it is inferred that repair processes operating along the chromosomal DNA are one order of magnitude more efficient than those operating along the extrachromosomal DNA. This conclusion is reinforced by the fact that the absence of repair in the system Escherichia coli AB2480 uvrA recA-lambdacI857 ind red gives the expected ratio of 80/1 for the uv sensitivity of cells and that of intracellular phage

Ascorbic acid (AA) metabolism in protection against radiation damage

International Nuclear Information System (INIS)

Rose, R.C.; Koch, M.J.

1986-01-01

The possibility is considered that AA protects tissues against radiation damage by scavenging free radicals that result from radiolysis of water. A physiologic buffer (pH 6.7) was incubated with 14 C-AA and 1 mM thiourea (to slow spontaneous oxidation of AA). Aliquots were assayed by HPLC and scintillation spectrometry to identify the 14 C-label. Samples exposed to Cobalt-60 radiation had a half time of AA decay of 30 minutes) indicating that AA scavenges radiation-induced free radicals and forms the ascorbate free radical (AFR). Pairs of 14 C-AFR disproportionate, with the net effect of 14 C-dehydroascorbic acid formation from 14 C-AA. Having established that AFR result from ionizing radiation in an aqueous solution, the possibility was evaluated that a tissue factor reduces AFR. Cortical tissue from the kidneys of male rats was minced, homogenized in buffer and centrifuged at 8000 xg. The supernatant was found to slow the rate of radiation-induced AA degradation by > 90% when incubated at 23 0 C in the presence of 15 μM 14 C-AA. Samples of supernatant maintained at 100 0 C for 10 minutes or precipitated with 5% PCA did not prevent radiation-induced AA degradation. AA may have a specific role in scavenging free radicals generated by ionizing radiation and thereby protect body tissues

First improvements in the detection and quantification of label-free nucleic acids by laser-induced breakdown spectroscopy: Application to the deoxyribonucleic acid micro-array technology

International Nuclear Information System (INIS)

Le Meur, Julien; Menut, Denis; Wodling, Pascal; Salmon, Laurent; Thro, Pierre-Yves; Chevillard, Sylvie; Ugolin, Nicolas

2008-01-01

The accurate quantification of nucleic acids is essential in many fields of modern biology and industry, and in some cases requires the use of fluorescence labeling. Yet, in addition to standardization problems and quantification reproducibility, labeling can modify the physicochemical properties of molecules or affect their stability. To address these limitations, we have developed a novel method to detect and quantify label-free nucleic acids. This method is based on stoichiometric proportioning of phosphorus in the nucleic acid skeleton, using laser-induced breakdown spectroscopy, and a specific statistical analysis, which indicates the error probability for each measurement. The results obtained appear to be quantitative, with a limit of detection of 10 5 nucleotides/μm 2 (i.e. 2 x 10 13 phosphorus atoms/cm 2 ). Initial micro-array analysis has given very encouraging results, which point to new ways of quantifying hybridized nucleic acids. This is essential when comparing molecules of different sequences, which is presently very difficult with fluorescence labeling

First improvements in the detection and quantification of label-free nucleic acids by laser-induced breakdown spectroscopy: Application to the deoxyribonucleic acid micro-array technology

Energy Technology Data Exchange (ETDEWEB)

Le Meur, Julien [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France); Menut, Denis [Laboratoire de Reactivite des Surfaces et des Interfaces, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Wodling, Pascal [Laboratoire d' Interaction Laser-Matiere, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Salmon, Laurent [Laboratoire de Reactivite des Surfaces et des Interfaces, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Thro, Pierre-Yves [Laboratoire d' Interaction Laser-Matiere, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Chevillard, Sylvie [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France); Ugolin, Nicolas [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France)], E-mail: nugolin@cea.fr

2008-04-15

The accurate quantification of nucleic acids is essential in many fields of modern biology and industry, and in some cases requires the use of fluorescence labeling. Yet, in addition to standardization problems and quantification reproducibility, labeling can modify the physicochemical properties of molecules or affect their stability. To address these limitations, we have developed a novel method to detect and quantify label-free nucleic acids. This method is based on stoichiometric proportioning of phosphorus in the nucleic acid skeleton, using laser-induced breakdown spectroscopy, and a specific statistical analysis, which indicates the error probability for each measurement. The results obtained appear to be quantitative, with a limit of detection of 10{sup 5} nucleotides/{mu}m{sup 2} (i.e. 2 x 10{sup 13} phosphorus atoms/cm{sup 2}). Initial micro-array analysis has given very encouraging results, which point to new ways of quantifying hybridized nucleic acids. This is essential when comparing molecules of different sequences, which is presently very difficult with fluorescence labeling.

Effect of Salicylic Acid on Alleviating of Electrolyte Leakage and Flower Organ Damage in Apricot (Prunus armeniaca L. cv. ‘Shahroudi’

Directory of Open Access Journals (Sweden)

Morteza ALIREZAIE NOGHONDAR

2013-02-01

Full Text Available One of the most important limiting factors in spread of apricot in Iran is late spring frost, which damages flower bud and decrease total yield of crop. It has been found that salicylic acid (SA plays a beneficial role during plant response to chilling and freezing stresses. To evaluate the effects of salicylic acid on alleviating of cold stress, the flower buds (FBs of Prunus armeniaca L. cv. ‘Shahroudi’ were sprayed at pink cluster stage with SA at 4 levels (0, 0.5, 1 and 2 mM and were then exposed to artificial cold stress (4 h at -4°C or without cold stress (+ 25. Experimental attributes including electrolyte leakage of FBs and percentage of damage (PD of pistil, anthers and petals to temperature treatments were determined. The results showed that at -4°C the lowest and highest PD and EL of FBs were observed in application of 0.5 and 0 mM SA, respectively. The highest and lowest PD of flower organ and EL were obtained in application of 0 and 2 mM SA, respectively at +25°C. Based on the results of this experiment, SA alleviates the negative effect of cold stress on electrolyte leakage and flower organ damages in apricot cv. ‘Shahroudi’, depending on the concentrations of SA used.

Interactive Effects of Jasmonic Acid, Salicylic Acid, and Gibberellin on Induction of Trichomes in Arabidopsis1

Science.gov (United States)

Traw, M. Brian; Bergelson, Joy

2003-01-01

Leaf trichomes protect plants from attack by insect herbivores and are often induced following damage. Hormonal regulation of this plant induction response has not been previously studied. In a series of experiments, we addressed the effects of artificial damage, jasmonic acid, salicylic acid, and gibberellin on induction of trichomes in Arabidopsis. Artificial damage and jasmonic acid caused significant increases in trichome production of leaves. The jar1-1 mutant exhibited normal trichome induction following treatment with jasmonic acid, suggesting that adenylation of jasmonic acid is not necessary. Salicylic acid had a negative effect on trichome production and consistently reduced the effect of jasmonic acid, suggesting negative cross-talk between the jasmonate and salicylate-dependent defense pathways. Interestingly, the effect of salicylic acid persisted in the nim1-1 mutant, suggesting that the Npr1/Nim1 gene is not downstream of salicylic acid in the negative regulation of trichome production. Last, we found that gibberellin and jasmonic acid had a synergistic effect on the induction of trichomes, suggesting important interactions between these two compounds. PMID:14551332

LSD and Genetic Damage

Science.gov (United States)

Dishotsky, Norman I.; And Others

1971-01-01

Reviews studies of the effects of lysergic acid diethylamide (LSD) on man and other organisms. Concludes that pure LSD injected in moderate doses does not cause chromosome or detectable genetic damage and is not a teratogen or carcinogen. (JM)

MRI Overestimates Excitotoxic Amygdala Lesion Damage in Rhesus Monkeys

Directory of Open Access Journals (Sweden)

Benjamin M. Basile

2017-06-01

Full Text Available Selective, fiber-sparing excitotoxic lesions are a state-of-the-art tool for determining the causal contributions of different brain areas to behavior. For nonhuman primates especially, it is advantageous to keep subjects with high-quality lesions alive and contributing to science for many years. However, this requires the ability to estimate lesion extent accurately. Previous research has shown that in vivo T2-weighted magnetic resonance imaging (MRI accurately estimates damage following selective ibotenic acid lesions of the hippocampus. Here, we show that the same does not apply to lesions of the amygdala. Across 19 hemispheres from 13 rhesus monkeys, MRI assessment consistently overestimated amygdala damage as assessed by microscopic examination of Nissl-stained histological material. Two outliers suggested a linear relation for lower damage levels, and values of unintended amygdala damage from a previous study fell directly on that regression line, demonstrating that T2 hypersignal accurately predicts damage levels below 50%. For unintended damage, MRI estimates correlated with histological assessment for entorhinal cortex, perirhinal cortex and hippocampus, though MRI significantly overestimated the extent of that damage in all structures. Nevertheless, ibotenic acid injections routinely produced extensive intentional amygdala damage with minimal unintended damage to surrounding structures, validating the general success of the technique. The field will benefit from more research into in vivo lesion assessment techniques, and additional evaluation of the accuracy of MRI assessment in different brain areas. For now, in vivo MRI assessment of ibotenic acid lesions of the amygdala can be used to confirm successful injections, but MRI estimates of lesion extent should be interpreted with caution.

Citric acid improves lead (pb) phytoextraction in brassica napus L. by mitigating pb-induced morphological and biochemical damages.

Science.gov (United States)

Shakoor, Muhammad Bilal; Ali, Shafaqat; Hameed, Amjad; Farid, Mujahid; Hussain, Sabir; Yasmeen, Tahira; Najeeb, Ullah; Bharwana, Saima Aslam; Abbasi, Ghulam Hasan

2014-11-01

Phytoextraction is an environmentally friendly and a cost-effective strategy for remediation of heavy metal contaminated soils. However, lower bioavailability of some of the metals in polluted environments e.g. lead (Pb) is a major constraint of phytoextraction process that could be overcome by applying organic chelators. We conducted a glasshouse experiment to evaluate the role of citric acid (CA) in enhancing Pb phytoextraction. Brassica napus L. seedlings were grown in hydroponic media and exposed to various treatments of Pb (50 and 100 μM) as alone or in combination with CA (2.5mM) for six weeks. Pb-induced damage in B. napus toxicity was evident from elevated levels of malondialdehyde (MDA) and H2O2 that significantly inhibited plant growth, biomass accumulation, leaf chlorophyll contents and gas exchange parameters. Alternatively, CA application to Pb-stressed B. napus plants arrested lipid membrane damage by limiting MDA and H2O2 production and by improving antioxidant enzyme activities. In addition, CA significantly increased the Pb accumulation in B. napus plants. The study concludes that CA has a potential to improve Pb phytoextraction without damaging plant growth. Copyright © 2014 Elsevier Inc. All rights reserved.

Manual resurfacing and trichloroacetic acid for the treatment of patients with widespread actinic damage. Clinical and histologic observations.

Science.gov (United States)

Cooley, J E; Casey, D L; Kauffman, C L

1997-05-01

A facial resurfacing regimen combining manual abrasion of the skin and 25% trichloroacetic acid has been reported to produce excellent results, but the histologic depth of injury produced by this technique has not been studied. To describe our experience with this technique treating patients with extensive actinic damage and to determine the histologic depth of injury produced. We treated 40 patients using manual resurfacing and trichloroacetic acid, primarily for widespread actinic keratoses. Resurfacing tools included silicone carbide sandpaper, drywall screen, electrocautery tip cleaners, abrasive pads, scalpel blades, and curettes. Four patients underwent sequential biopsies to evaluate the depth of wounding using this technique. Manual resurfacing combined with trichloroacetic acid consistently produced excellent cosmetic results and nearly complete eradication of actinic keratoses. Histologically, treated areas showed replacement of the dermal elastotic band by newly formed collagen, a significantly deeper level of wounding than the Jessner's/35% trichloroacetic acid peel. There was no evidence for foreign body granulomas clinically or histologically as a result of the abrasive materials. The deeper level of this peel explains the improved cosmetic outcome and greater eradication of actinic keratoses. This treatment is particularly well suited for patients with extensive photodamage and widespread actinic keratoses.

2-Aminopurine hairpin probes for the detection of ultraviolet-induced DNA damage

International Nuclear Information System (INIS)

El-Yazbi, Amira F.; Loppnow, Glen R.

2012-01-01

Highlights: ► Molecular beacon with 2AP bases detects DNA damage in a simple mix-and-read assay. ► Molecular beacons with 2AP bases detect damage at a 17.2 nM limit of detection. ► The 2AP molecular beacon is linear over a 0–3.5 μM concentration range for damage. - Abstract: Nucleic acid exposure to radiation and chemical insults leads to damage and disease. Thus, detection and understanding DNA damage is important for elucidating molecular mechanisms of disease. However, current methods of DNA damage detection are either time-consuming, destroy the sample, or are too specific to be used for generic detection of damage. In this paper, we develop a fluorescence sensor of 2-aminopurine (2AP), a fluorescent analogue of adenine, incorporated in the loop of a hairpin probe for the quantification of ultraviolet (UV) C-induced nucleic acid damage. Our results show that the selectivity of the 2AP hairpin probe to UV-induced nucleic acid damage is comparable to molecular beacon (MB) probes of DNA damage. The calibration curve for the 2AP hairpin probe shows good linearity (R 2 = 0.98) with a limit of detection of 17.2 nM. This probe is a simple, fast and economic fluorescence sensor for the quantification of UV-induced damage in DNA.

Gamma Amino Butyric Acid Attenuates Liver and Kidney Damage Associated with Insulin Alteration in γ-Irradiated and Streptozotocin-Treated Rats

International Nuclear Information System (INIS)

Saada, H.N.; Eltahawy, N.A.; Hammad, A.S.; Morcos, N.Y.S.

2016-01-01

Gamma aminobutyric acid (GABA) is one of the inhibitory neurotransmitters that may have the ability to relive the intensity of stress. The aim of the current study was to evaluate the role of γ-amino butyric acid (GABA) in modulating insulin disturbance associated with liver and kidney damage in γ-irradiated and streptozotocin-treated rats. Irradiation was performed by whole body exposure to 6 Gy from a Cs-137 source. Streptozotocin (STZ) was administered in a single intraperitoneal dose (60 mg/kg body weight). GABA (200 mg/Kg body weight/day) was administered daily via gavages during 3 weeks to γ-irradiated and STZ-treated-rats. The results obtained showed that γ-irradiation induced hyperglycemia, hyperinsulinaemia and insulin resistance (similar to type 2 Diabetes), while STZ-treatment produced hyperglycemia, insulin deficiency with no insulin resistance detected (similar to type 1 Diabetes). In both cases, significant increases of alanine amino transferase (ALT) and aspartate amino transferase (AST) activities, urea and creatinine levels were recorded in the serum. These changes were associated with oxidative damage to the liver and kidney tissues notified by significant decreases of superoxide dismutase (SOD ), catalase and glutathione peroxidase ( GSH-Px) activities in parallel to significant increases of malondialdehyde (MDA) and advanced oxidation protein products ( AOPP) levels. The administration of GABA to irradiated as well as STZ-treated rats regulated insulin and glucose levels, minimized oxidative stress and reduced the severity of liver and kidney damage. It could be concluded that GABA could be a useful adjunct to reduce some metabolic complications associated with insulin deficiency and insulin resistance

Supplementation with beta-hydroxy-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) reduces signs and symptoms of exercise-induced muscle damage in man.

Science.gov (United States)

van Someren, Ken A; Edwards, Adam J; Howatson, Glyn

2005-08-01

This study examined the effects of beta-hydroxyl-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) supplementation on signs and symptoms of exercise-induced muscle damage following a single bout of eccentrically biased resistance exercise. Six non-resistance trained male subjects performed an exercise protocol designed to induce muscle damage on two separate occasions, performed on the dominant or non-dominant arm in a counter-balanced crossover design. Subjects were assigned to an HMB/KIC (3 g HMB and 0.3 g alpha-ketoisocaproic acid, daily) or placebo treatment for 14 d prior to exercise in the counter-balanced crossover design. One repetition maximum (1RM), plasma creatine kinase activity (CK), delayed onset muscle soreness (DOMS), limb girth, and range of motion (ROM) were determined pre-exercise, at 1h, 24 h, 48 h, and 72 h post-exercise. DOMS and the percentage changes in 1RM, limb girth, and ROM all changed over the 72 h period (P HMB//IC supplementation attenuated the CK response, the percentage decrement in 1RM, and the percentage increase in limb girth (P HMB/KIC treatment. In conclusion, 14 d of HMB and KIC supplementation reduced signs and symptoms of exercise-induced muscle damage in non-resistance trained males following a single bout of eccentrically biased resistance exercise.

Actual implications of industrial smoke damage to forests

Energy Technology Data Exchange (ETDEWEB)

Zieger, E

1955-01-01

General problems of smoke-induced damages, diagnosis, and control methods are reviewed. Damages caused by etching of leaves and needles are mostly of an acute and local character. Damages due to disturbed assimilation, caused primarily by sulfur dioxide, are of the greatest importance economically. Sulfur dioxide is less harmful in winter and during night hours. Acids and sulfur dioxide both turn the soil acid, and affect the edaphon. Such damages are primarily of chronic character. Different diagnostic methods such as plant, soil, and air analyses should be combined to obtain reliable results. Due to the complexity of the processes involved in smoke damages, biological tests are best in diagnosis. The sunlight test exploits the fact that branches cut from smoke-damaged trees lose their needles more readily than such from intact trees. Haertels turbidity test is based on the increased wax secretion by smoke-damaged needles. The appraisal of damages is made by evaluation of the economic losses after the limitation of the smoke-affected area. The possible control measures in forestry are the breeding of smoke-resistant species and liming, while the pollution control techniques presently available in industry are unsatisfactory, the major problems being caused by sulfur dioxide. Standardization of thresholds and maximum allowable concentrations, as well as cooperation of forestry and industries are imperative. 12 references.

Systemic lupus erythematosus and the Crithidia luciliae immunofluorescent test

International Nuclear Information System (INIS)

Whitehouse, I.J.; Fehr, K.; Wagenhaeuser, F.J.

1983-01-01

A comparative study of the Crithidia luciliae immunofluorescence (CL-IF) assay and an adapted Farr radioimmunoassay (RIA), for the measurement of antibodies to native deoxyribonucleic acid, was performed using forty-two sera from patients with systematic lupus erythematosus (SLE) and another forty-two from patients with rheumatoid arthritis. Both assays were specific for SLE. The CL-IF assay was statistically significantly more sensitive than the adapted RIA assay. This significant difference was due to greater sensitivity of the CL-IF assay in the cases of sera from patients with SLE of slight activity. Additional advantages of the CL-IF assay were its use to classify the immunoglobulin types of the antibodies (most commonly IgG or IgM) and to measure complement-fixing antibodies to native deoxyribonucleic acid; it affords a simple method of selecting and following SLE patients at risk of developing severe renal disease. These advantages plus the simplicity and inexpensiveness of the CL-IF assay make it a useful tool, especially for use in small laboratories, for the study of antibodies to native deoxyribonucleic acid in patients with SLE. (orig.) [de

Amelioration of radiation induced DNA damage and biochemical alterations by Punica Granatum (L) extracts and synthetic ellagic acid in Swiss albino mice

International Nuclear Information System (INIS)

Satheesh Kumar Bhandary, B.; Sharmila, K.P.; Suchetha Kumari, N.; Vadisha Bhat, S.; Sherly, Sharmila; Sanjeev, Ganesh

2013-01-01

Radiation therapy has been used in cancer treatment for many decades; Although effective in killing tumor cells, ROS produced in radiotherapy threaten the integrity and survival of surrounding normal cells. ROS are scavenged by radioprotectors before they can interact with biochemical molecules, thus reducing harmful effects of radiation. The pomegranate, Punica granatum L., an ancient, mystical, and highly distinctive fruit, is the predominant member of the Punicaceae family. It is used in several systems of medicine for a variety of ailments. The objective of the present study was to investigate the protective effects of ethanolic extracts of pomegranate whole fruit (EPWF) and seeds (EPS) and Synthetic Ellagic acid (EA) against Electron Beam Radiation (EBR) induced DNA damage and biochemical alterations in Swiss Albino mice. The extracts and synthetic compound were assessed for its radical scavenging property by DPPH radical scavenging and Ferric Reducing Antioxidant Power assays. The animals were treated with 200 mg/kg body wt. of pomegranate extracts and Ellagic acid for 15 days before exposure to 6 Gy of EBR. Radiation induced DNA damage was assessed by comet assay in the peripheral blood lymphocytes of mice. The biochemical estimations were carried out in the serum and RBC lysate of the animals. The plant extracts and synthetic compound exhibited good radical scavenging and reducing properties.The pretreated animals before irradiation caused a reduction in the comet length, olive tail moment, % DNA in tail when compared to irradiated group. The biochemical parameters such as lipid peroxidation was significantly depleted in the treated groups when compared to irradiated group followed by significant elevation in reduced glutathione. Our findings indicate the ameliorating effects of pomegranate extracts and synthetic ellagic acid on radiation induced DNA damage and biochemical changes in mice may be due to its free radical scavenging and increased antioxidant

Effect of the methyl gallate on the damage produced by radiation in leucocytes of peripheral blood of In vivo mouse; Efecto del metil galato sobre el dano producido por radiacion en leucocitos de sangre periferica de raton In vivo

Energy Technology Data Exchange (ETDEWEB)

Zarco M, A [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)

2007-07-01

The ionizing radiation produces a great variety of lesions in the deoxyribonucleic acid (DNA) through the formation of free radicals (RL), reason why the study about those made up with possible radioprotective property has been increased. The methyl gallate (MeG) it is an antioxidant derived of plants with capacity to capture RL. The objective of the present work was to determine the effect of the methyl gallate on the damage in the DNA taken place by gamma radiation in leukocytes of peripheral blood of in vivo mouse. The experimental design consisted of 4 groups of mice: It has a witness of the solvent group, dimethylsulfoxide (DMSO), in which was administer by intraperitoneal via 0.4 mL of a solution 1:8 of DMSO: H{sub 2}O; a second group, denominated MeG witness, it was administered intraperitoneally with a dose of 0.1 {mu} moles/g of weight. Another group was used as radiation witness, reason why it was only treated with 1 Gray (Gy) of gamma radiation coming from a cobalt 60 source. At last, the group denominated problem it was administered with 0.1 {mu} moles of MeG/g of corporal weight 30 previous minutes to the irradiation with 1 Gy. In the comparison of the damage and repair curves obtained with the unicellular in gel electrophoresis technique among the irradiated groups, it was determined that there is one significant reduction of 15% in the DNA damage observed to the two minutes postradiation in the problem group with respect to the radiation witness. It was concluded that this decrease is due to the antioxidant effect of the methyl gallate and that therefore this compound has possibilities to act as radioprotector. (Author)

Exercise-induced muscle damage is reduced in resistance-trained males by branched chain amino acids: a randomized, double-blind, placebo controlled study

Directory of Open Access Journals (Sweden)

Howatson Glyn

2012-07-01

Full Text Available Abstract Background It is well documented that exercise-induced muscle damage (EIMD decreases muscle function and causes soreness and discomfort. Branched-chain amino acid (BCAA supplementation has been shown to increase protein synthesis and decrease muscle protein breakdown, however, the effects of BCAAs on recovery from damaging resistance training are unclear. Therefore, the aim of this study was to examine the effects of a BCAA supplementation on markers of muscle damage elicited via a sport specific bout of damaging exercise in trained volunteers. Methods Twelve males (mean ± SD age, 23 ± 2 y; stature, 178.3 ± 3.6 cm and body mass, 79.6 ± 8.4 kg were randomly assigned to a supplement (n = 6 or placebo (n = 6 group. The damaging exercise consisted of 100 consecutive drop-jumps. Creatine kinase (CK, maximal voluntary contraction (MVC, muscle soreness (DOMS, vertical jump (VJ, thigh circumference (TC and calf circumference (CC were measured as markers of muscle damage. All variables were measured immediately before the damaging exercise and at 24, 48, 72 and 96 h post-exercise. Results A significant time effect was seen for all variables. There were significant group effects showing a reduction in CK efflux and muscle soreness in the BCAA group compared to the placebo (P Conclusion The present study has shown that BCAA administered before and following damaging resistance exercise reduces indices of muscle damage and accelerates recovery in resistance-trained males. It seems likely that BCAA provided greater bioavailablity of substrate to improve protein synthesis and thereby the extent of secondary muscle damage associated with strenuous resistance exercise. Clinical Trial Registration Number: NCT01529281.

Determination of furan precursors and some thermal damage markers in baby foods: ascorbic acid, dehydroascorbic acid, hydroxymethylfurfural and furfural.

Science.gov (United States)

Mesías-García, Marta; Guerra-Hernández, Eduardo; García-Villanova, Belén

2010-05-26

The presence of ascorbic acid (AA), vitamin C (AA + dehydroascorbic acid (DHAA)) and furfural as potential precursors of furan in commercial fruit and vegetable jarred baby food was studied. Hydroxymethylfurfural (HMF) was also determined and used, together with furfural levels, as markers of thermal damage. AA, calculated DHAA and vitamin C values ranged between 22.4 and 103, 2.9 and 13.8, and 32.1 and 113.2 mg/100 g, respectively, in fruit-based baby food. However, no trace of AA was found in the vegetable-based baby food samples tested, probably because these samples are not enriched in vitamin C and the content of this vitamin in fresh vegetables is destroyed during processing. Furfural values ranged from not detected to 236 microg/100 g, being higher in vegetable samples than in fruit samples possibly because of greater AA degradation favored by a higher pH in the vegetable samples. HMF values (range: not detected-959 microg/100 g), however, were higher in the fruit samples, probably due to greater carbohydrate content degradation and as a consequence of the Maillard reaction, favored by a lower pH in these samples. According to these results, HMF would be the optimum indicator of thermal treatment for fruits, and furfural for vegetables. The higher furfural content of vegetable baby food could be considered an index of greater AA degradation and, therefore, the furan content might be higher in this kind of sample than in fruit-based baby food.

Detection, characterization and measure of a new radiation-induced damage in isolated and cellular DNA; Detection, caracterisation et mesure d'un nouveau dommage radio-induit de l'ADN isole et cellulaire

Energy Technology Data Exchange (ETDEWEB)

Regulus, P

2006-10-15

Deoxyribonucleic acid (DNA) contains the genetic information and chemical injury to this macromolecule may have severe biological consequences. We report here the detection of 4 new radiation-induced DNA lesions by using a high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) approach. For that purpose, the characteristic fragmentation of most 2'-deoxy-ribo nucleosides, the loss of 116 Da corresponding to the loss of the 2-deoxyribose moiety, was used in the so-called neutral loss mode of the HPLC-MS/MS. One of the newly detected lesions, named dCyd341 because it is a 2'-deoxycytidine modification exhibiting a molecular weight of 341 Da, was also detected in cellular DNA. Characterization of this modified nucleoside was performed using NMR and exact mass determination of the product obtained by chemical synthesis. A mechanism of formation was then proposed, in which the first event is the H-abstraction at the C4 position of a 2-deoxyribose moiety. Then, the sugar modification produced exhibits a reactive aldehyde that, through reaction with a vicinal cytosine base, gives rise to dCyd341. dCyd341 could be considered as a complex damage since its formation involves a DNA strand break and a cross-link between a damaged sugar residue and a vicinal cytosine base located most probably on the complementary DNA strand. In addition to its characterization, preliminary biological studies revealed that cells are able to remove the lesion from DNA. Repair studies have revealed the ability of cells to excise the lesion. Identification of the repair systems involved could represent an interesting challenge. (author)

The effects of dietary boric acid and borax supplementation on lipid peroxidation, antioxidant activity, and DNA damage in rats.

Science.gov (United States)

Ince, Sinan; Kucukkurt, Ismail; Cigerci, Ibrahim Hakki; Fatih Fidan, A; Eryavuz, Abdullah

2010-07-01

The aims of this study were to clarify the effects of high dietary supplementation with boric acid and borax, called boron (B) compounds, on lipid peroxidation (LPO), antioxidant activity, some vitamin levels, and DNA damage in rats. Thirty Sprague Dawley male rats were divided into three equal groups: the animals in the first group (control) were fed with a standard rodent diet containing 6.4 mg B/kg, and the animals in the experimental group were fed with a standard rodent diet added with a supra-nutritional amount of boric acid and borax (100 mg B/kg) throughout the experimental period of 28 days. The B compounds decreased malondialdehyde (MDA), DNA damage, the protein carbonyl content (PCO) level in blood, and glutathione (GSH) concentration in the liver, Cu-Zn superoxide dismutase (SOD), and catalase (CAT) activity in the kidney. The B compounds increased GSH concentration in blood and the vitamin C level in plasma. Consequently, our results demonstrate that B supplementation (100 mg/kg) in diet decreases LPO, and enhances the antioxidant defense mechanism and vitamin status. There are no differences in oxidant/antioxidant balance and biochemical parameters except for serum vitamin A and liver GSH concentration, between the boron compounds used in this study. Crown Copyright 2010. Published by Elsevier GmbH. All rights reserved.

Damaged-self recognition as a general strategy for injury detection

OpenAIRE

Heil, Martin

2012-01-01

Plants perceive endogenous molecules or their fragments as signals of danger when these appear at increased concentrations in the extracellular space, and they respond with increased endogenous levels of jasmonic acid. The wound hormone jasmonic acid represents a central player in the induced resistance of plants to herbivore feeding and infection by necrotrophic pathogens. This ‘damaged self recognition’ mechanism of plants exhibits astonishing similarities to the perception of ‘damage-assoc...

Modeling cellular effects of coal pollutants

International Nuclear Information System (INIS)

Anon.

1981-01-01

The goal of this project is to develop and test models for the dose and dose-rate dependence of biological effects of coal pollutants on mammalian cells in tissue culture. Particular attention is given to the interaction of pollutants with the genetic material (deoxyribonucleic acid, or NDA) in the cell. Unlike radiation, which can interact directly with chromatin, chemical pollutants undergo numerous changes before the ultimate carcinogen becomes covalently bound to the DNA. Synthetic vesicles formed from a phospholipid bilayer are being used to investigate chemical transformations that may occur during the transport of pollutants across cellular membranes. The initial damage to DNA is rapidly modified by enzymatic repair systems in most living organisms. A model has been developed for predicting the effects of excision repair on the survival of human cells exposed to chemical carcinogens. In addition to the excision system, normal human cells also have tolerance mechanisms that permit continued growth and division of cells without removal of the damage. We are investigating the biological effect of damage passed to daughter cells by these tolerance mechanisms

The role of membrane cholesterol in determining bile acid cytotoxicity and cytoprotection of ursodeoxycholic acid

Science.gov (United States)

Zhou, Yong; Doyen, Rand; Lichtenberger, Lenard M.

2013-01-01

In cholestatic liver diseases, the ability of hydrophobic bile acids to damage membranes of hepatocytes/ductal cells contributes to their cytotoxicity. However, ursodeoxycholic acid (UDC), a hydrophilic bile acid, is used to treat cholestasis because it protects membranes. It has been well established that bile acids associate with and solubilize free cholesterol (CHOL) contained within the lumen of the gallbladder because of their structural similarities. However, there is a lack of understanding of how membrane CHOL, which is a well-established membrane stabilizing agent, is involved in cytotoxicity of hydrophobic bile acids and the cytoprotective effect of UDC. We utilized phospholipid liposomes to examine the ability of membrane CHOL to influence toxicity of individual bile acids, such as UDC and the highly toxic sodium deoxycholate (SDC), as well as the cytoprotective mechanism of UDC against SDC-induced cytotoxicity by measuring membrane permeation and intramembrane dipole potential. The kinetics of bile acid solubilization of phosphatidylcholine liposomes containing various levels of CHOL was also characterized. It was found that the presence of CHOL in membranes significantly reduced the ability of bile acids to damage synthetic membranes. UDC effectively prevented damaging effects of SDC on synthetic membranes only in the presence of membrane CHOL, while UDC enhances the damaging effects of SDC in the absence of CHOL. This further demonstrates that the cytoprotective effects of UDC depend upon the level of CHOL in the lipid membrane. Thus, changes in cell membrane composition, such as CHOL content, potentially influence the efficacy of UDC as the primary drug used to treat cholestasis. PMID:19150330

Amplification of deoxyribonucleic acid (DNA) fragment using two ...

African Journals Online (AJOL)

user

2011-04-11

Apr 11, 2011 ... polymerases on this method, whether different lengths of. DNA fragments could be amplified by two-step PCR and the difference of DNA product quality produced by the two methods. MATERIALS AND METHODS. PCR template and reagents. Enterobacteria phage lambda DNA (GenBank no: V00636) ...

The effects of ionizing radiation on deoxyribonucleic acid

International Nuclear Information System (INIS)

Cullis, P.M.; Jones, G.D.D.; Lea, J.; Symons, M.C.R.; Sweeney, M.

1987-01-01

Exposure of frozen, deoxygenated, aqueous solutions of DNA to 60 Co γ-rays at 77 K results in the formation of guanine-centred radical-cations (Gsup(radical +)) and thymine-centred radical-anions (Tsup(radical -)). Both these primary centres are thought to be capable of inducing DNA strand-breaks, both single (SSB) and double (DSB). When low concentrations of a range of water-soluble thiols were added, there was no change in the initial yield of Gsup(radical +) and Tsup(radical -) as judged from the e.s.r. spectra. However, on annealing, the normal pattern of radical reactions was abruptly modified at ca. 200 ± 5 K, with the DNA-centred radicals being dramatically reduced in concentration with the concomitant growth of e.s.r. signals characteristic of RSsup(radical) - SR - radical-anions. For example, for solutions containing one thiol molecule per 25 base-pairs, there was a loss of ca. 50% in the concentration of DNA radicals at this temperature. Using plasmid DNA, the change in the numbers of SSBs and DSBs was monitored when various thiols were present. There was a marked fall in the yields of both these events, in accord with the e.s.r. results. It is concluded that these thiols react by hydrogen-atom donation to various DNA radicals thereby forming RSsup(radical) radicals which rapidly form RSsup(radical)SR - radical-anions. It seems that, under our conditions, neither of these sulphur radicals is able to react with DNA. In the presence of oxygen, the results are less definitive, the degree of repair being a function of the relative concentrations of oxygen and thiol. E.s.r. evidence for the formation of DNA-centred peroxy radicals and their reaction with thiols is presented, and also there is evidence for the addition of oxygen to RSsup(radical) radicals to give RSOsup(anion radical) 2 radicals. The latter are probably able to react with DNA. (author)

Hydrochloric acid poisoning

Science.gov (United States)

Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

Diagnosis of ventricular drainage-related bacterial meningitis by broad-range real-time polymerase chain reaction

DEFF Research Database (Denmark)

Deutch, Susanna; Dahlberg, Daniel; Hedegaard, Jesper

2007-01-01

OBJECTIVE: To compare a broad-range real-time polymerase chain reaction (PCR) diagnostic strategy with culture to evaluate additional effects on the etiological diagnosis and the quantification of the bacterial load during the course of ventricular drainage-related bacterial meningitis (VR......-BM). METHODS: We applied a PCR that targeted conserved regions of the 16S ribosomal ribonucleic acid gene to cerebrospinal fluid (CSF) samples from patients with external ventricular drainage or a ventriculoperitoneal shunt during the course of VR-BM. We compared the PCR results with CSF cultures. A total...... of 350 routine CSF samples were consecutively collected from 86 patients. The CSF deoxyribonucleic acid was automatically purified and subjected to PCR. Amplicons from the PCR samples that were positive for VR-BM were subsequently deoxyribonucleic acid sequenced for final identification. Clinical data...

Protective Effect of Alpha Lipoic Acid on Rat Sciatic Nerve Ischemia Reperfusion Damage

Directory of Open Access Journals (Sweden)

Ozan Turamanlar

2015-06-01

Full Text Available Background: Alpha lipoic acid is a potent antioxidant that plays numerous roles in human health. This study examined the effect of ALA on rat sciatic nerve ischemia reperfusion damage. Aims: Protective effect of alpha lipoic acid (ALA on sciatic nerve following ischemia-reperfusion in rats was investigated by using light microscopy and biochemical methods. Provided that the protective effect of ALA on sciatic nerve is proven, we think the damage to the sciatic nerve that has already occurred or might occur in patients for various reasons maybe prevented or stopped by giving ALA in convenient doses. Study Design: Animal experiment. Methods: Forty-two adult male Sprague-Dawley rats (250-300 grams were used in this study. Rats were randomly divided into six groups including one control (Group 1, one sham (Group 2, two ischemia-reperfusion (Groups 3 and 4 and two treatment groups (Groups5 and 6. Doses of 60 and 100 mg/kg ALA were given (Group 5 and 6 intra peritoneally twice, 1 and 24 hours before the ischemia to each treatment group. Ischemia was carried out the abdominal aorta starting from the distal part of the renal vein for two hours followed by reperfusion for three hours. In immunohistochemical methods, fibronectin immunoreactivity was analyzed. For biochemical analyses, the tissues were taken in eppendorf microtubes and superoxide dismutase (SOD and glutathione peroxidase (GSHPx enzyme activities as well as malondialdehyde (MDA and nitricoxide (NO levels were measured. Results: Fibronectin was observed to have increased significantly in the ischemia group; on the other hand, it was observed to have decreased in parallel to the doses in the ALA groups. Biochemical studies showed that SOD and GSHPx declined with ischemia-reperfusion, but the activities of these enzymes were increased in the treatment groups in parallel with the dose. It was found that increased MDA levels with ischemia-reperfusion were decreased in parallel with ALA dose

Sequence analysis of putative swrW gene required for surfactant ...

African Journals Online (AJOL)

Serratia marcescens produces biosurfactant serrawettin, essential for its population migration behavior. Serrawettin W1 was revealed to be an antibiotic serratamolide that makes it significant for deoxyribonucleic acid (DNA) and protein sequence analysis. Four nucleotide and amino-acid sequences from local strains ...

Oxidative Stress as an Important Factor in the Pathophysiology of alzheimer's Disease

Directory of Open Access Journals (Sweden)

Tanise Gemelli,

2013-06-01

Full Text Available Oxidative stress has been associated to play a crucial role in the pathogenesis of many diseases, including neurodegenerative diseases. Alzheimer's disease is an age-related neurodegenerative disorder, which is recognized as the most common form of dementia. In this article, the aim was to review the involvement of oxidative stress on Alzheimer's disease. Alzheimer's disease is histopathologically characterized by the presence of extracellular amyloid plaques, intracellular neurofibrillary tangles, the presence of oligomers of amyloid-? peptide and loss of synapses. Moreover, the brain and the nervous system are more prone to oxidative stress and oxidative damage influences the neurodegenerative diseases. However, increased oxidative damage, mitochondrial dysfunction, accumulation of oxidized aggregated proteins, inflammation, and defects in proteins constitute complex intertwined pathologies that lead to neuronal cell death. Mitochondrial mutations on deoxyribonucleic acid and oxidative stress contribute to aging, affecting different cell signaling systems, as well as the connectivity and neuronal cell death may lead to the largest risk factor for neurodegenerative diseases such as Alzheimer's Disease.

Investigating the effects of dietary folic acid on sperm count, DNA damage and mutation in Balb/c mice

International Nuclear Information System (INIS)

Swayne, Breanne G.; Kawata, Alice; Behan, Nathalie A.; Williams, Andrew; Wade, Mike G.; MacFarlane, Amanda J.; Yauk, Carole L.

2012-01-01

To date, fewer than 50 mutagens have been studied for their ability to cause heritable mutations. The majority of those studied are classical mutagens like radiation and anti-cancer drugs. Very little is known about the dietary variables influencing germline mutation rates. Folate is essential for DNA synthesis and methylation and can impact chromatin structure. We therefore determined the effects of folic acid-deficient (0 mg/kg), control (2 mg/kg) and supplemented (6 mg/kg) diets in early development and during lactation or post-weaning on mutation rates and chromatin quality in sperm of adult male Balb/c mice. The sperm chromatin structure assay and mutation frequencies at expanded simple tandem repeats (ESTRs) were used to evaluate germline DNA integrity. Treatment of a subset of mice fed the control diet with the mutagen ethylnitrosourea (ENU) at 8 weeks of age was included as a positive control. ENU treated mice exhibited decreased cauda sperm counts, increased DNA fragmentation and increased ESTR mutation frequencies relative to non-ENU treated mice fed the control diet. Male mice weaned to the folic acid deficient diet had decreased cauda sperm numbers, increased DNA fragmentation index, and increased ESTR mutation frequency. Folic acid deficiency in early development did not lead to changes in sperm counts or chromatin integrity in adult mice. Folic acid supplementation in early development or post-weaning did not affect germ cell measures. Therefore, adequate folic acid intake in adulthood is important for preventing chromatin damage and mutation in the male germline. Folic acid supplementation at the level achieved in this study does not improve nor is it detrimental to male germline chromatin integrity.

Investigating the effects of dietary folic acid on sperm count, DNA damage and mutation in Balb/c mice

Energy Technology Data Exchange (ETDEWEB)

Swayne, Breanne G.; Kawata, Alice [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); Behan, Nathalie A. [Nutrition Research Division, Food Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); Williams, Andrew; Wade, Mike G. [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); MacFarlane, Amanda J. [Nutrition Research Division, Food Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); Yauk, Carole L., E-mail: carole.yauk@hc-sc.ga.ca [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada)

2012-09-01

To date, fewer than 50 mutagens have been studied for their ability to cause heritable mutations. The majority of those studied are classical mutagens like radiation and anti-cancer drugs. Very little is known about the dietary variables influencing germline mutation rates. Folate is essential for DNA synthesis and methylation and can impact chromatin structure. We therefore determined the effects of folic acid-deficient (0 mg/kg), control (2 mg/kg) and supplemented (6 mg/kg) diets in early development and during lactation or post-weaning on mutation rates and chromatin quality in sperm of adult male Balb/c mice. The sperm chromatin structure assay and mutation frequencies at expanded simple tandem repeats (ESTRs) were used to evaluate germline DNA integrity. Treatment of a subset of mice fed the control diet with the mutagen ethylnitrosourea (ENU) at 8 weeks of age was included as a positive control. ENU treated mice exhibited decreased cauda sperm counts, increased DNA fragmentation and increased ESTR mutation frequencies relative to non-ENU treated mice fed the control diet. Male mice weaned to the folic acid deficient diet had decreased cauda sperm numbers, increased DNA fragmentation index, and increased ESTR mutation frequency. Folic acid deficiency in early development did not lead to changes in sperm counts or chromatin integrity in adult mice. Folic acid supplementation in early development or post-weaning did not affect germ cell measures. Therefore, adequate folic acid intake in adulthood is important for preventing chromatin damage and mutation in the male germline. Folic acid supplementation at the level achieved in this study does not improve nor is it detrimental to male germline chromatin integrity.

Azithromycin and erythromycin ameliorate the extent of colonic damage induced by acetic acid in rats

International Nuclear Information System (INIS)

Mahgoub, Afaf; El-Medany, Azza; Mustafa, Ali; Arafah, Maha; Moursi, Mahmoud

2005-01-01

Ulcerative colitis is a common inflammatory bowel disease (IBD) of unknown etiology. Recent studies have revealed the role of some microorganisms in the initiation and perpetuation of IBD. The role of antibiotics in the possible modulation of colon inflammation is still uncertain. In this study, we evaluated the effects of two macrolides, namely azithromycin and erythromycin, at different doses on the extent and severity of ulcerative colitis caused by intracolonic administration of 3% acetic acid in rats. The lesions and the inflammatory response were assessed by histology and measurement of myeloperoxidase (MPO) activity, nitric oxide synthetase (NOS) and tumor necrosis factor alpha (TNFα) in colonic tissues. Inflammation following acetic acid instillation was characterized by oedema, diffuse inflammatory cell infiltration and necrosis. Increase in MPO, NOS and TNFα was detected in the colonic tissues. Administration of either azithromycin or erythromycin at different dosage (10, 20 and 40 mg/kg orally, daily for 5 consecutive days) significantly (P < 0.05) reduced the colonic damage, MPO and NOS activities as well as TNFα level. This reduction was highly significant with azithromycin when given at a dose of 40 mg/kg. It is concluded that azithromycin and erythromycin may have a beneficial therapeutic role in ulcerative colitis

Effects of carotenoids on damage of biological lipids induced by gamma irradiation

International Nuclear Information System (INIS)

Saito, Takeshi; Fujii, Noriko

2014-01-01

Carotenoids are considered to be involved in the radioresistant mechanisms of radioresistant bacteria. In these bacterial cells, carotenoids are present in biological lipids, and therefore may be related to the radiation-induced damage of lipids. However, only limited data are available for the role of carotenoids in such damage. In this study, we irradiated an α-linolenic acid–benzene solution with gamma rays and analyzed the resulting oxidative degradation and peroxidation damage in the presence or absence of two typical carotenoids: β-carotene and astaxanthin. The analyses revealed that oxidative degradation and peroxidation of α-linolenic acid, as evaluated by the amount of malondialdehyde and conjugated diene formed, respectively, increased in a dose-dependent manner. Moreover, 8.5×10 −3 M β-carotene inhibited gamma radiation-induced oxidative degradation of α-linolenic acid, whereas 5.0×10 −5 and 5.0×10 −6 M β-carotene, and 5.0×10 −7 and 5.0×10 −8 M astaxanthin promoted degradation. In contrast, neither β-carotene nor astaxanthin affected peroxidation of α-linolenic acid. These results suggest that an optimum concentration of carotenoids in radioresistant bacteria protects biological lipid structures from radiation-induced damage. - Highlights: • Gamma radiation dose-dependently increases degradation levels of α-linolenic acid. • Gamma radiation dose-dependently increases peroxidation levels of α-linolenic acid. • An optimum concentration of carotenoids inhibits degradation of α-linolenic acid. • Relatively low concentrations of carotenoids promote degradation of α-linolenic acid. • Carotenoids do not affect the peroxidation level of α-linolenic acid

Dose effects on damage of thymidylic acid and its components irradiated by A N+ ion beam

International Nuclear Information System (INIS)

Shao Chunlin; Yu Zengliang

1996-08-01

Research into damage of DNA components is an important field in mechanism study to the low energy ion beam irradiation. It was found that the UV difference spectra of irradiated thymine (T) had two positive peaks caused by the changes of π electron conjugation of the pyrimidine ring, and that the residual activity of T sample irradiated by a N + ion beam was not influenced by treatments of acid and alkali as well as heat. In addition, the residual activities of irradiated thymidine (dTR) and thymidine 5'-phosphate (5'-dTMP) with and without treating of strong acid and strong alkali were also measured. With UV absorption spectrophotometry, the yield of T released from the irradiated samples of dTR and 5'-dTMP and the residual concentration of these target molecules were deduced, and it was found that the yield of T increased when the solution of the irradiated dTR sample was treated by heat but decreased when this solution was treated by acid and alkali for these treatments splitting T-S or T-S-P. On the other hand, the yield of inorganic phosphate released from the irradiated 5'-dTMP was investigated and found that it was increased by the treatment of alkali and that the increase degree was depended on the time scale of the treatment. Moreover, G(Pi) of the irradiated 5'-dTMP non-linearly decreased with increasing dose. (10 figs.)

STING-IRF3 Triggers Endothelial Inflammation in Response to Free Fatty Acid-Induced Mitochondrial Damage in Diet-Induced Obesity

Science.gov (United States)

Mao, Yun; Luo, Wei; Zhang, Lin; Wu, Weiwei; Yuan, Liangshuai; Xu, Hao; Song, Juhee; Fujiwara, Keigi; Abe, Jun-ichi; LeMaire, Scott A.; Wang, Xing Li; Shen, Ying. H.

2017-01-01

Objective Metabolic stress in obesity induces endothelial inflammation and activation, which initiates adipose tissue inflammation, insulin resistance, and cardiovascular diseases. However, the mechanisms underlying endothelial inflammation induction are not completely understood. Stimulator of interferon genes (STING) is an important molecule in immunity and inflammation. In the present study, we sought to determine the role of STING in palmitic acid (PA)-induced endothelial activation/inflammation. Approach and Results In cultured endothelial cells, PA treatment activated STING, as indicated by its perinuclear translocation and binding to interferon regulatory factor 3 (IRF3), leading to IRF3 phosphorylation and nuclear translocation. The activated IRF3 bound to the promoter of intercellular adhesion molecule 1 (ICAM-1) and induced ICAM-1 expression and monocyte–endothelial cell adhesion. When analyzing the upstream signaling, we found that PA activated STING by inducing mitochondrial damage. PA treatment caused mitochondrial damage and leakage of mitochondrial DNA (mtDNA) into the cytosol. Through the cytosolic DNA sensor cyclic GMP-AMP synthase (cGAS), the mitochondrial damage and leaked cytosolic mtDNA activated the STING-IRF3 pathway and increased ICAM-1 expression. In mice with diet-induced obesity, the STING-IRF3 pathway was activated in adipose tissue. However, STING deficiency (Stinggt/gt) partially prevented diet-induced adipose tissue inflammation, obesity, insulin resistance, and glucose intolerance. Conclusions The mitochondrial damage-cGAS-STING-IRF3 pathway is critically involved in metabolic stress-induced endothelial inflammation. STING may be a potential therapeutic target for preventing cardiovascular diseases and insulin resistance in obese individuals. PMID:28302626

Increased Chromosomal Radiosensitivity in Women Carrying BRCA1/BRCA2 Mutations Assessed With the G2 Assay

International Nuclear Information System (INIS)

Ernestos, Beroukas; Nikolaos, Pandis; Koulis, Giannoukakos; Eleni, Rizou; Konstantinos, Beroukas; Alexandra, Giatromanolaki; Michael, Koukourakis

2010-01-01

Purpose: Several in vitro studies suggest that BRCA1 and BRCA2 mutation carriers present increased sensitivity to ionizing radiation. Different assays for the assessment of deoxyribonucleic acid double-strand break repair capacity have been used, but results are rather inconsistent. Given the concerns about the possible risks of breast screening with mammography in mutation carrier women and the potentially damaging effects of radiotherapy, the purpose of this study was to further investigate the radiosensitivity of this population. Methods and Materials: The G2 chromosomal radiosensitivity assay was used to assess chromosomal breaks in lymphocyte cultures after exposure to 1 Gy. A group of familiar breast cancer patients carrying a mutation in the BRCA1 or BRCA2 gene (n = 15) and a group of healthy mutation carriers (n = 5) were investigated and compared with a reference group of healthy women carrying no mutation (n = 21). Results: BRCA1 and BRCA2 mutation carriers had a significantly higher number of mean chromatid breaks per cell (p = 0.006) and a higher maximum number of breaks (p = 0.0001) as compared with their matched controls. Both healthy carriers and carriers with a cancer history were more radiosensitive than controls (p = 0.002 and p = 0.025, respectively). Age was not associated with increased radiosensitivity (p = 0.868). Conclusions: Our results indicate that BRCA1 and BRCA2 mutation carriers show enhanced radiosensitivity, presumably because of the involvement of the BRCA genes in deoxyribonucleic acid repair and cell cycle control mechanisms.

Effect of astaxanthin in combination with alpha-tocopherol or ascorbic acid against oxidative damage in diabetic ODS rats.

Science.gov (United States)

Nakano, Masako; Onodera, Aya; Saito, Emi; Tanabe, Miyako; Yajima, Kazue; Takahashi, Jiro; Nguyen, Van Chuyen

2008-08-01

The present study was performed to investigate the effect of astaxanthin in combination with other antioxidants against oxidative damage in streptozotocin (STZ)-induced diabetic Osteogenic Disorder Shionogi (ODS) rats. Diabetic-ODS rats were divided into five groups: control, astaxanthin, ascorbic acid, alpha-tocopherol, and tocotrienol. Each of the four experimental groups was administered a diet containing astaxanthin (0.1 g/kg), in combination with ascorbic acid (3.0 g/kg), alpha-tocopherol (0.1 g/kg), or tocotrienol (0.1 g/kg) for 20 wk. The effects of astaxanthin with other antioxidants on lipid peroxidation, urinary 8-hydroxy-2-deoxyguanosine (8-OHdG) excretion, serum creatinine (Cr) level, creatinine clearance (Ccr), and urinary protein content were assessed. The serum lipid peroxide levels and chemiluminescent (CL) intensity in the liver of the alpha-tocopherol and tocotrienol groups were significantly reduced in comparison to that of the control group. In the alpha-tocopherol group, urinary 8-OHdG excretion, serum Cr level, Ccr, urinary albumin excretion, and urinary protein concentration were significantly decreased as compared with those in the control group. Additionally, the CL intensity in the kidney of the alpha-tocopherol group was significantly lower, but that of the ascorbic acid group was significantly higher than that in the control group. These results indicate that dietary astaxanthin in combination with alpha-tocopherol has an inhibitory effect on oxidative stress. On the other hand, our study suggests that excessive ascorbic acid intake increases lipid peroxidation in diabetic rats.

Pollution Damage and Protection of Asian Hair

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Xin Qu

2018-02-01

Full Text Available Cigarette smoke was used to simulate a polluted environment and an experiment was performed to reveal how virgin and bleached hair are damaged by a polluted environment. The dry/wet combability, surface contact angle, tryptophan content, and cuticle morphology of the smoke exposed hair were evaluated, and compared to unexposed virgin hair. The results showed that pollution exposure can cause significant chemical damage to hair. In particular, virgin hair exposure to pollution can cause damage to the hair cuticles (higher wet/dry combing, protein degradation, and a more hydrophilic hair surface. The experiment also demonstrated that the styling polymer, polyimide-1 (isobutylene/dimethyl amino propyl maleimide/ethoxylated maleimide/maleic acid copolymer, can provide effective protection against such hair damage.

HIV-1 in the RNA world: Transcription regulation, miRNAs and antiviral RNAs

NARCIS (Netherlands)

Harwig, A.

2015-01-01

All organisms, from bacteria to human, use three biological molecules that each serve critical functions in the expression of genes in the cell. These are deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and proteins. RNA is synthesized from DNA in a process called transcription. RNA differs from

Fundamental Approaches in Molecular Biology for Communication Sciences and Disorders

Science.gov (United States)

Bartlett, Rebecca S.; Jette, Marie E.; King, Suzanne N.; Schaser, Allison; Thibeault, Susan L.

2012-01-01

Purpose: This contemporary tutorial will introduce general principles of molecular biology, common deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein assays and their relevance in the field of communication sciences and disorders. Method: Over the past 2 decades, knowledge of the molecular pathophysiology of human disease has…

Endoplasmic reticulum stress involved in high-fat diet and palmitic acid-induced vascular damages and fenofibrate intervention

Energy Technology Data Exchange (ETDEWEB)

Lu, Yunxia, E-mail: wwwdluyx@sina.com [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); The Comprehensive Laboratory, Anhui Medical University, Hefei, Anhui 230032 (China); Cheng, Jingjing [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Chen, Li [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Department of Medical Laboratory, Anhui Provincial Hospital, Hefei, Anhui 230001 (China); Li, Chaofei; Chen, Guanjun [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Gui, Li [The Comprehensive Laboratory, Anhui Medical University, Hefei, Anhui 230032 (China); Shen, Bing [Department of Physiology, Anhui Medical University, Hefei, Anhui 230032 (China); Zhang, Qiu [Department of Endocrinology, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022 (China)

2015-02-27

Fenofibrate (FF) is widely used to lower blood lipids in clinical practice, but whether its protective effect on endothelium-dependent vasodilatation (EDV) in thoracic aorta is related with endoplasmic reticulum (ER) stress remains unknown. In this study, female Sprauge Dawley rats were divided into standard chow diets (SCD), high-fat diets (HFD) and HFD plus FF treatment group (HFD + FF) randomly. The rats of latter two groups were given HFD feeding for 5 months, then HFD + FF rats were treated with FF (30 mg/kg, once daily) via gavage for another 2 months. The pathological and tensional changes, protein expression of eNOS, and ER stress related genes in thoracic aorta were measured. Then impacts of palmitic acid (PA) and FF on EDV of thoracic aorta from normal female SD rats were observed. Ultimately the expression of ER stress related genes were assessed in primary mouse aortic endothelial cells (MAEC) treated by fenofibric acid (FA) and PA. We found that FF treatment improved serum lipid levels and pathological changes in thoracic aorta, accompanied with decreased ER stress and increased phosphorylation of eNOS. FF pretreatment also improved EDV impaired by different concentrations of PA treatment. The dose- and time-dependent inhibition of cell proliferation by PA were inverted by FA pretreatment. Phosphorylation of eNOS and expression of ER stress related genes were all inverted by FA pretreatment in PA-treated MAEC. Our findings show that fenofibrate recovers damaged EDV by chronic HFD feeding and acute stimulation of PA, this effect is related with decreased ER stress and increased phosphorylation of eNOS. - Highlights: • Fenofibrate treatment improved pathological changes in thoracic aorta by chronic high-fat-diet feeding. • Fenofibrate pretreatment improved endothelium-dependent vasodilation impaired by different concentrations of palmitic acid. • The inhibition of proliferation in endothelial cells by palmitic acid were inverted by fenofibric

Protective Efficacy of Alpha-lipoic Acid against AflatoxinB1-induced Oxidative Damage in the Liver

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Y. Li

2014-06-01

Full Text Available Alpha-lipoic acid (α-LA is not only involved in energy metabolism, but is also a powerful antioxidant that can protect against hepatic oxidative stress induced by some drugs, toxins, or under various physiological and pathophysiological conditions. Here, we investigated the effect of α-LA against liver oxidative damage in broilers exposed to aflatoxin B1 (AFB1. Birds were randomly divided into four groups and assigned different diets: basal diet, 300 mg/kg α-LA supplementation in basal diet, diet containing 74 μg/kg AFB1, and 300 mg/kg α-LA supplementation in diet containing 74 μg/kg AFB1, for 3 weeks. The results revealed that the addition of 300 mg/kg α-LA protected against the liver function damage of broilers induced by chronic low dose of AFB1 as estimated by a significant (p<0.05 change in levels of plasma total protein, albumin, alkaline phosphatase and the activities of liver glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase. The histopathological analysis also showed that liver tissues were injured in the AFB1 diet, but this effect was alleviated by the addition of 300 mg/kg α-LA. Additionally, AFB1 induced a profound elevation of oxidative stress in birds, as indicated by an increase in malondialdehyde level, a decrease in glutathione peroxidase activity and a depletion of the glutathione content in the liver. All of these negative effects were inhibited by treatment with α-LA. Our results suggest that the inhibition of AFB1-induced excess production of lipid peroxides and the maintenance of intracellular antioxidant status may play important roles in the protective effects of α-LA against AFB1-induced oxidative damage in the liver.

Kinetics of membrane damage to high (HNA) and low (LNA) nucleic acid bacterial clusters in drinking water by ozone, chlorine, chlorine dioxide, monochloramine, ferrate(VI), and permanganate.

Science.gov (United States)

Ramseier, Maaike K; von Gunten, Urs; Freihofer, Pietro; Hammes, Frederik

2011-01-01

Drinking water was treated with ozone, chlorine, chlorine dioxide, monochloramine, ferrate(VI), and permanganate to investigate the kinetics of membrane damage of native drinking water bacterial cells. Membrane damage was measured by flow cytometry using a combination of SYBR Green I and propidium iodide (SGI+PI) staining as indicator for cells with permeabilized membranes and SGI alone to measure total cell concentration. SGI+PI staining revealed that the cells were permeabilized upon relatively low oxidant exposures of all tested oxidants without a detectable lag phase. However, only ozonation resulted in a decrease of the total cell concentrations for the investigated reaction times. Rate constants for the membrane damage reaction varied over seven orders of magnitude in the following order: ozone > chlorine > chlorine dioxide ≈ ferrate > permanganate > chloramine. The rate constants were compared to literature data and were in general smaller than previously measured rate constants. This confirmed that membrane integrity is a conservative and therefore safe parameter for disinfection control. Interestingly, the cell membranes of high nucleic acid (HNA) content bacteria were damaged much faster than those of low nucleic acid (LNA) content bacteria during treatment with chlorine dioxide and permanganate. However, only small differences were observed during treatment with chlorine and chloramine, and no difference was observed for ferrate treatment. Based on the different reactivity of these oxidants it was suggested that HNA and LNA bacterial cell membranes have a different chemical constitution. Copyright © 2010 Elsevier Ltd. All rights reserved.

Antiproliferative potential of aqueous leaf extract of Mucuna pruriens ...

African Journals Online (AJOL)

. pruriens and weight determination was employed using standard protocol. Comet assay protocol was employed to determine level of deoxyribonucleic acid (DNA) fragmentation while hematoxylin and eosin were used for histological assay.

Alpha-Lipoic acid counteracts the promoted oxidative DNA damage in the liver of septic rats

International Nuclear Information System (INIS)

Abd-Allah, Adel R.A.

2006-01-01

Viral, parasitic infections and chemical carcinogens are among the etiological factors of liver cancer. It seems important to study the initiating and promoting agents to evaluate the etiology and prevention of such life threatening disease. Intestine-derived bacteria product, lipopolysaccharide (LPS), is mainly detoxified by the liver. It has shown to induce a state of oxidative DNA damage is not fully investigated. Increased oxidative DNA damage and rate of cell proliferation may initiate or even promote cancer. In the present work, the capability of LPS to induce 8-hydroxydeoxyguanosine (8-HDG), a specific DNA adduct for oxidative DNA damage, in rat livers is tested. Furthermore, a possible protective effect of alpha lipoic acid (ALA) is also assessed. Investigated parameters are liver contents of glutathione (GSH), lipid peroxides (MDA), nitric oxide (NO) and 8-HDG in the liver-extracted DNA. Serum activities of ALT, AST and GGT as liver-function markers as well as IL2 are assessed. Moreover, liver histology is examined. LPS was given doses of 1, 3, 5, 7 and 9 mg/kg once i.p. while, the rat mortality was examined 24 hours later. ALA was given in doses of 50, 100 and 200 mg/kg once i.p. 3h before LPS is found to be 5mg/kg. LPS increased the level of 8-HDG, MDA and NO in the liver. It also induced acute liver necrosis and inflammatory cell infiltration as shown in liver-histopathology and in the significant increase in the activities of ALT, AST and GGT. LPS increased the serum level of IL2 as well. The dose 200mg/kg of ALA revealed a 100% protection against LPS-induced lethality. It also, prevented the LPS-induced increase in 8-HDG in liver extracted DNA, the liver contents of MDA and NO. ALA also rescued the LPS-induced GSH depletion. It corrected the liver function as shown by the prevention of increases in the activity of ALT, AST and GGT with a remarkable improvement in the liver histology. Moreover, it prevented the increase in serum level of IL2. These

Chemical consequences of irradiating nucleic acids

International Nuclear Information System (INIS)

Ward, J.F.

1976-01-01

On the basis of literature data, a discussion is presented of the DNA damage which would be produced in a cellular environment and an attempt is made to place this damage in perspective as a potential hazard in food irradiation. The topics discussed are radiation damage mechanisms, OH reactions with DNA, base products, sugar products, and evaluation of damage from irradiated nucleic acids

Eubacterium rangiferina, a novel usnic acid-resistant bacterium from the reindeer rumen

Science.gov (United States)

Sundset, Monica A.; Kohn, Alexandra; Mathiesen, Svein D.; Præsteng, Kirsti E.

2008-08-01

Reindeer are able to eat and utilize lichens as an important source of energy and nutrients. In the current study, the activities of antibiotic secondary metabolites including usnic, antranoric, fumarprotocetraric, and lobaric acid commonly found in lichens were tested against a collection of 26 anaerobic rumen bacterial isolates from reindeer ( Rangifer tarandus tarandus) using the agar diffusion method. The isolates were identified based on their 16S ribosomal ribonucleic acid (rRNA) gene sequences. Usnic acid had a potent antimicrobial effect against 25 of the isolates, belonging to Clostridiales, Enterococci, and Streptococci. Isolates of Clostridia and Streptococci were also susceptible to atranoric and lobaric acid. However, one isolate (R3_91_1) was found to be resistant to usnic, antranoric, fumarprotocetraric, and lobaric acid. R3_91_1 was also seen invading and adhering to lichen particles when grown in a liquid anaerobic culture as demonstrated by transmission electron microscopy. This was a Gram-negative, nonmotile rod (0.2-0.7 × 2.0-3.5 μm) with a deoxyribonucleic acid G + C content of 47.0 mol% and main cellular fatty acids including 15:0 anteiso-dimethyl acetal (DMA), 16:0 iso-fatty acid methyl ester (FAME), 13:0 iso-3OH FAME, and 17:0 anteiso-FAME, not matching any of the presently known profiles in the MIDI database. Combined, the phenotypic and genotypic traits including the 16S rRNA gene sequence show that R3_91_1 is a novel species inside the order Clostridiales within the family Lachnospiraceae, for which we propose the name Eubacterium rangiferina. This is the first record of a rumen bacterium able to tolerate and grow in the presence of usnic acid, indicating that the rumen microorganisms in these animals have adapted mechanisms to deal with lichen secondary metabolites, well known for their antimicrobial and toxic effects.

Anaerobic accumulation of short-chain fatty acids from algae enhanced by damaging cell structure and promoting hydrolase activity.

Science.gov (United States)

Feng, Leiyu; Chen, Yunzhi; Chen, Xutao; Duan, Xu; Xie, Jing; Chen, Yinguang

2018-02-01

Short-chain fatty acid (SCFAs) produced from harvested algae by anaerobic fermentation with uncontrolled pH was limited due to the solid cell structure of algae. This study, therefore, was undertaken to enhance the generation of SCFAs from algae by controlling the fermentation pH. pH influenced not only the total SCFAs production, but the percentage of individual SCFA. The maximal yield of SCFAs occurred at pH 10.0 and fermentation time of 6 d (3161 mg COD/L), which mainly contained acetic and iso-valeric acids and was nearly eight times that at uncontrolled pH (392 mg COD/L). Mechanism exploration revealed at alkaline pH, especially at pH 10.0, not only the cell structure of algae was damaged effectively, but also activities and relative quantification of hydrolases as well as the abundance of microorganisms responsible for organics hydrolysis and SCFAs production were improved. Also, the released microcystins from algae were removed efficiently during alkaline anaerobic fermentation. Copyright © 2017 Elsevier Ltd. All rights reserved.

DNA damage-inducible transcripts in mammalian cells

International Nuclear Information System (INIS)

Fornace, A.J. Jr.; Alamo, I. Jr.; Hollander, M.C.

1988-01-01

Hybridization subtraction at low ratios of RNA to cDNA was used to enrich for the cDNA of transcripts increased in Chinese hamster cells after UV irradiation. Forty-nine different cDNA clones were isolated. Most coded for nonabundant transcripts rapidly induced 2- to 10-fold after UV irradiation. Only 2 of the 20 cDNA clones sequenced matched known sequences (metallothionein I and II). The predicted amino acid sequence of one cDNA had two localized areas of homology with the rat helix-destabilizing protein. These areas of homology were at the two DNA-binding sites of this nucleic acid single-strand-binding protein. The induced transcripts were separated into two general classes. Class I transcripts were induced by UV radiation and not by the alkylating agent methyl methanesulfonate. Class II transcripts were induced by UV radiation and by methyl methanesulfonate. Many class II transcripts were induced also by H2O2 and various alkylating agents but not by heat shock, phorbol 12-tetradecanoate 13-acetate, or DNA-damaging agents which do not produce high levels of base damage. Since many of the cDNA clones coded for transcripts which were induced rapidly and only by certain types of DNA-damaging agents, their induction is likely a specific response to such damage rather than a general response to cell injury

Potential therapeutic effects of branched-chain amino acids supplementation on resistance exercise-based muscle damage in humans

Directory of Open Access Journals (Sweden)

da Luz Claudia R

2011-12-01

Full Text Available Abstract Branched-chain amino acids (BCAA supplementation has been considered an interesting nutritional strategy to improve skeletal muscle protein turnover in several conditions. In this context, there is evidence that resistance exercise (RE-derived biochemical markers of muscle soreness (creatine kinase (CK, aldolase, myoglobin, soreness, and functional strength may be modulated by BCAA supplementation in order to favor of muscle adaptation. However, few studies have investigated such effects in well-controlled conditions in humans. Therefore, the aim of this short report is to describe the potential therapeutic effects of BCAA supplementation on RE-based muscle damage in humans. The main point is that BCAA supplementation may decrease some biochemical markers related with muscle soreness but this does not necessarily reflect on muscle functionality.

Human papilloma virus prevalence in laryngeal squamous cell carcinoma.

Science.gov (United States)

Gungor, A; Cincik, H; Baloglu, H; Cekin, E; Dogru, S; Dursun, E

2007-08-01

To determine the prevalence and type of human papilloma virus deoxyribonucleic acid (DNA) in cases of laryngeal squamous cell carcinoma. We analysed the prevalence of human papilloma virus infection in archived paraffin block specimens taken from 99 cases of laryngeal squamous cell carcinoma between 1990 and 2005, using polymerase chain reaction techniques. Biopsy specimens from five proven verrucous skin lesions were used as positive controls, and peripheral blood samples from five healthy volunteers were used as negative controls. Four test samples were found to have inadequate deoxyribonucleic acid purity and were therefore excluded from the study. Human papilloma virus deoxyribonucleic acid was detected in seven of 95 cases of laryngeal squamous cell carcinoma (7.36 per cent). Human papilloma virus genotyping revealed double human papilloma virus infection in three cases and single human papilloma virus infection in the remaining four cases. The human papilloma virus genotypes detected were 6, 11 and 16 (the latter detected in only one case). In our series, a very low human papilloma virus prevalence was found among laryngeal squamous cell carcinoma cases. The human papilloma virus genotypes detected were mostly 6 and/or 11, and 16 in only one case. To the best of our knowledge, this is the first report of human papilloma virus prevalence in laryngeal squamous cell carcinoma, based on polymerase chain reaction genotyping in a Turkish population.

10-Hydroxy-2-decenoic acid prevents ultraviolet A-induced damage and matrix metalloproteinases expression in human dermal fibroblasts.

Science.gov (United States)

Zheng, Jinfen; Lai, Wei; Zhu, Guoxing; Wan, Miaojian; Chen, Jian; Tai, Yan; Lu, Chun

2013-10-01

10-Hydroxy-2-decenoic acid (10-HDA) is a major fatty acid component of royal jelly, which has been reported to have a variety of beneficial pharmacological characteristics. However, the effects of 10-HDA on skin photoageing and its potential mechanism of action are unclear. We investigated the protective effects of 10-HDA on ultraviolet (UV) A-induced damage in human dermal fibroblasts (HDFs). We then explored the inhibitory effects of 10-HDA on UVA-induced matrix metalloproteinases (MMPs) expression and elucidated the signalling pathways controlling MMPs inhibition. Primary human dermal fibroblasts were exposed to UVA. Cell proliferation, cellular senescent state and collagen content were analysed using CCK-8, senescence-associated β-galactosidase staining and Sircol collagen assay, respectively. Fluorometric assays were performed to detect the formation of reactive oxygen species (ROS) in the cells. The mRNA levels of MMP-1, MMP-3 and type I (α1) collagen were determined by quantitative real-time PCR. Western blot was applied to detect the expression of MMP-1, MMP-3, JNK and p38 MAPK. HDFs treated with 10-HDA were significantly protected from UVA-induced cytotoxicity, ROS, cellular senescence and stimulated collagen production. Moreover, 10-HDA suppressed the UVA-induced expression of MMP-1 and MMP-3 at both the transcriptional and protein levels. Treatment with 10-HDA also reduced the UVA-induced activation of the JNK and p38 MAPK pathways. The data obtained in this study provide evidence that 10-HDA could prevent UVA-induced damage and inhibit MMP-1 and MMP-3 expressions. Therefore, 10-HDA may be a potential agent for the prevention and treatment of skin photoageing. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.

Raman spectroscopic study of plasma-treated salmon DNA

Energy Technology Data Exchange (ETDEWEB)

Lee, Geon Joon; Kim, Yong Hee; Choi, Eun Ha [Plasma Bioscience Research Center, Kwangwoon University, Seoul 139-701 (Korea, Republic of); Kwon, Young-Wan [Department of Chemistry, Korea University, Seoul 136-701 (Korea, Republic of)

2013-01-14

In this research, we studied the effect of plasma treatment on the optical/structural properties of the deoxyribonucleic acid (DNA) extracted from salmon sperm. DNA-cetyltrimethylammonium (CTMA) films were obtained by complexation of DNA with CTMA. Circular dichroism (CD) and Raman spectra indicated that DNA retained its double helical structure in the solid film. The Raman spectra exhibited several vibration modes corresponding to the nuclear bases and the deoxyribose-phosphate backbones of the DNA, as well as the alkylchains of CTMA. Dielectric-barrier-discharge (DBD) plasma treatment induced structural modification and damage to the DNA, as observed by changes in the ultraviolet-visible absorption, CD, and Raman spectra. The optical emission spectra of the DBD plasma confirmed that DNA modification was induced by plasma ions such as reactive oxygen species and reactive nitrogen species.

Robust and efficient direct multiplex amplification method for large-scale DNA detection of blood samples on FTA cards

International Nuclear Information System (INIS)

Jiang Bowei; Xiang Fawei; Zhao Xingchun; Wang Lihua; Fan Chunhai

2013-01-01

Deoxyribonucleic acid (DNA) damage arising from radiations widely occurred along with the development of nuclear weapons and clinically wide application of computed tomography (CT) scan and nuclear medicine. All ionizing radiations (X-rays, γ-rays, alpha particles, etc.) and ultraviolet (UV) radiation lead to the DNA damage. Polymerase chain reaction (PCR) is one of the most wildly used techniques for detecting DNA damage as the amplification stops at the site of the damage. Improvements to enhance the efficiency of PCR are always required and remain a great challenge. Here we establish a multiplex PCR assay system (MPAS) that is served as a robust and efficient method for direct detection of target DNA sequences in genomic DNA. The establishment of the system is performed by adding a combination of PCR enhancers to standard PCR buffer, The performance of MPAS was demonstrated by carrying out the direct PCR amplification on l.2 mm human blood punch using commercially available primer sets which include multiple primer pairs. The optimized PCR system resulted in high quality genotyping results without any inhibitory effect indicated and led to a full-profile success rate of 98.13%. Our studies demonstrate that the MPAS provides an efficient and robust method for obtaining sensitive, reliable and reproducible PCR results from human blood samples. (authors)

Plasma concentrations of water-soluble vitamins in metabolic ...

African Journals Online (AJOL)

2012-01-21

Jan 21, 2012 ... histamine, hemoglobin, deoxyribonucleic acid (DNA), and ribonucleic .... workers who had more years of education and were better informed ..... Osuntokun BO, Aladetoyinbo A, Bademosi O. Vitamin B nutrition in the. Nigerian ...

Disaster Doctor From 9/11 to Katrina

Science.gov (United States)

... cytosine—DNA (deoxyribonucleic acid) is life's chemical instruction manual, governing how cells grow, divide, live and die. ... DNA traces that could specifically link victim to identity—had vanished in Katrina's wake. Gone, too, were ...

PprA contributes to Deinococcus radiodurans resistance to nalidixic acid, genome maintenance after DNA damage and interacts with deinococcal topoisomerases.

Directory of Open Access Journals (Sweden)

Swathi Kota

Full Text Available PprA is known to contribute to Deinococcus radiodurans' remarkable capacity to survive a variety of genotoxic assaults. The molecular bases for PprA's role(s in the maintenance of the damaged D. radiodurans genome are incompletely understood, but PprA is thought to promote D. radiodurans's capacity for DSB repair. PprA is found in a multiprotein DNA processing complex along with an ATP type DNA ligase, and the D. radiodurans toposiomerase IB (DraTopoIB as well as other proteins. Here, we show that PprA is a key contributor to D. radiodurans resistance to nalidixic acid (Nal, an inhibitor of topoisomerase II. Growth of wild type D. radiodurans and a pprA mutant were similar in the absence of exogenous genotoxic insults; however, the pprA mutant exhibited marked growth delay and a higher frequency of anucleate cells following treatment with DNA-damaging agents. We show that PprA interacts with both DraTopoIB and the Gyrase A subunit (DraGyrA in vivo and that purified PprA enhances DraTopoIB catalysed relaxation of supercoiled DNA. Thus, besides promoting DNA repair, our findings suggest that PprA also contributes to preserving the integrity of the D. radiodurans genome following DNA damage by interacting with DNA topoisomerases and by facilitating the actions of DraTopoIB.

Browse Title Index

African Journals Online (AJOL)

Items 651 - 700 of 11090 ... ... results in physiological and behavioral changes in male mice ... Amplification of deoxyribonucleic acid (DNA) fragment using ... Vol 7, No 6 (2008), An allometric scaling law for understanding mammalian sleep ...

Ursolic Acid-Regulated Energy Metabolism—Reliever or Propeller of Ultraviolet-Induced Oxidative Stress and DNA Damage?

Directory of Open Access Journals (Sweden)

Yuan-Hao Lee

2014-08-01

sensitizer, ursolic acid (UA, which results in the metabolic adaptation of normal cells against UV-induced ROS, and the metabolic switch of tumor cells subject to UV-induced damage. The multifaceted natural compound, UA, specifically inhibits photo-oxidative DNA damage in retinal pigment epithelial cells while enhancing that in skin melanoma. Considering the UA-mediated differential effects on cell bioenergetics, this article reviews the disparities in glucose metabolism between tumor and normal cells, along with (peroxisome proliferator-activated receptor-γ coactivator 1α-dependent mitochondrial metabolism and redox (reduction-oxidation control to demonstrate UA-induced synthetic lethality in tumor cells.

Protective effects of ursodeoxycholic acid against 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced testicular damage in mice

International Nuclear Information System (INIS)

Kwon, Young-Il; Yeon, Je-Deuk; Oh, Seung-Min; Chung, Kyu-Hyuck

2004-01-01

The protective effect of ursodeoxycholic acid (UDCA), a biliary component found in bears, on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced testicular damage in mice was investigated. Fifty C57BL/6J mice were equally divided into five groups. The mice in the control group received the vehicle and standard chow. The single TCDD treatment group received 27.5 μg/kg of TCDD subcutaneously. The UDCA-included treatment group received pulverized chow containing 0.125%, 0.25% and 0.5% UDCA, respectively, for 70 days starting 10 days before TCDD injections. The body and testicular weights were shown to be decreased in the single TCDD treatment group, while the decrease was prevented by UDCA added to the chow. In addition, the decrease in the serum-luteinizing hormone (LH) or the follicle stimulating hormone (FSH) secondary to a TCDD injection was not observed in the UDCA-included treatment group. Contrary to the single TCDD treatment group, the germinal epithelium and intercellular space were relatively well preserved in the UDCA-included treatment group. Adding UDCA also normalized TCDD-induced irregular ultrastructural changes such as development of phagolysosomes, inflated smooth endoplasmic reticulum (SER), dilated and altered mitochondria, necrosis and completely damaged seminiferous tubules. Moreover, in the experiment for Arnt expression, UDCA added to the chow suppressed the TCDD-induced relocation of Arnt from the cytoplasm to the nuclei. In conclusion, TCDD-induced testicular toxicity was effectively protected by UDCA. There was almost complete recovery of the testes in the UDCA-included treatment group. Thus, UDCA may be useful for the prevention and treatment of TCDD-induced testicular damage

Effect of mercuric chloride on cellular morphology and acid phosphatase of tissue culture cells cultivated in suspension

Energy Technology Data Exchange (ETDEWEB)

Li, M F; Traxler, G S

1974-01-01

Cells exposed to HgCl/sub 2/ (0.5 mg/liter) increased dramatically in size and stained poorly with May-Grunwald Giemsa stain and exhibited incompleteness in cell division. When the cell DNA was stained by the Feulgen technique, many multinucleated cells were apparent in the cultures treated with HgCl/sub 2/. Additionally, enlargement and alteration of the nucleoli were evident. Electron-micrographs of the experimental cells revealed that microvilli, ribosomes, mitochondria, and endoplasmic reticula were abundant in the control cells, but in contrast a scarcity of these organelles was observed together with notable cytoplasmic vacuolation in the HgCl/sub 2/-treated cells. In addition the nucleolini of the treated cells were enlarged and had begun to fuse, producing a mulberry appearance. Electronmicroscopic detection of acid phosphatase activity in the cells indicated that the periplasmic enzyme activity was present in control cells, but not in the cells exposed to HgCl/sub 2/. The possible reaction of Hg/sup + +/ with deoxyribonucleic acid and disulfides is discussed with respect to the observed cytopathic effect and impaired enzyme activity. 10 references, 5 figures.

The role of folic acid and selenium against oxidative damage from ethanol in early life programming: a review.

Science.gov (United States)

Ojeda, Luisa; Nogales, Fátima; Murillo, Luisa; Carreras, Olimpia

2018-04-01

There are disorders in children, covered by the umbrella term "fetal alcohol spectrum disorder" (FASD), that occur as result of alcohol consumption during pregnancy and lactation. They appear, at least in part, to be related to the oxidative stress generated by ethanol. Ethanol metabolism generates reactive oxygen species and depletes the antioxidant molecule glutathione (GSH), leading to oxidative stress and lipid and protein damage, which are related to growth retardation and neurotoxicity, thereby increasing the incidence of FASD. Furthermore, prenatal and postnatal exposure to ethanol in dams, as well as increasing oxidation in offspring, causes malnutrition of several micronutrients such as the antioxidant folic acid and selenium (Se), affecting their metabolism and bodily distribution. Although abstinence from alcohol is the only way to prevent FASD, it is possible to reduce its harmful effects with a maternal dietary antioxidant therapy. In this review, folic acid and Se have been chosen to be analyzed as antioxidant intervention systems related to FASD because, like ethanol, they act on the methionine metabolic cycle, being related to the endogenous antioxidants GSH and glutathione peroxidase. Moreover, several birth defects are related to poor folate and Se status.

Hormesis in Cholestatic Liver Disease; Preconditioning with Low Bile Acid Concentrations Protects against Bile Acid-Induced Toxicity

NARCIS (Netherlands)

Verhaag, Esther M.; Buist-Homan, Manon; Koehorst, Martijn; Groen, Albert K.; Moshage, Han; Faber, Klaas Nico

2016-01-01

Introduction Cholestasis is characterized by accumulation of bile acids and inflammation, causing hepatocellular damage. Still, liver damage markers are highest in acute cholestasis and drop when this condition becomes chronic, indicating that hepatocytes adapt towards the hostile environment. This

Investigation of DNA strand breaks induced by 7Li and 12C ions

International Nuclear Information System (INIS)

Sui Li; Zhao Kui; Ni Meinan; Guo Jiyu; Luo Hongbing; Mei Junping; Lu Xiuqin; Zhou Ping

2004-01-01

Deoxyribonucleic acid (DNA) is an important biomacromolecule. It is a carrier of genetic information and a critical target for radiobiological effects. Numerous lesions have been identified in irradiated DNA. DNA double strand breaks (DSBs) are considered as the most important initial damage of all biological effects induced by ionizing radiation. In this experiment, DNA DSBs induced by heavy ions in the early period were investigated with atomic force microscopy (AFM). Choosing 7 Li and 12 C heavy ions with different LET values delivered by HI-13 tandem accelerator respectively, purified plasmid DNA samples in aqueous solution were irradiated at different doses. AFM was used for nanometer-level-structure analysis of DNA damage induced by these two kinds of heavy ions. Measurement of the DNA fragment lengths was accomplished with the Scion Image analyzed soft-ware. Change laws of three forms of DNA, supercoils, open circular and linear form as dose increased were obtained. Distributed function of DNA fragment length was also obtained, and fitted with Tsallis entropy statistical theory. (author)

Assessment of okadaic acid effects on cytotoxicity, DNA damage and DNA repair in human cells.

Science.gov (United States)

Valdiglesias, Vanessa; Méndez, Josefina; Pásaro, Eduardo; Cemeli, Eduardo; Anderson, Diana; Laffon, Blanca

2010-07-07

Okadaic acid (OA) is a phycotoxin produced by several types of dinoflagellates causing diarrheic shellfish poisoning (DSP) in humans. Symptoms induced by DSP toxins are mainly gastrointestinal, but the intoxication does not appear to be fatal. Despite this, this toxin presents a potential threat to human health even at concentrations too low to induce acute toxicity, since previous animal studies have shown that OA has very potent tumour promoting activity. However, its concrete action mechanism has not been described yet and the results reported with regard to OA cytotoxicity and genotoxicity are often contradictory. In the present study, the genotoxic and cytotoxic effects of OA on three different types of human cells (peripheral blood leukocytes, HepG2 hepatoma cells, and SHSY5Y neuroblastoma cells) were evaluated. Cells were treated with a range of OA concentrations in the presence and absence of S9 fraction, and MTT test and Comet assay were performed in order to evaluate cytotoxicity and genotoxicity, respectively. The possible effects of OA on DNA repair were also studied by means of the DNA repair competence assay, using bleomycin as DNA damage inductor. Treatment with OA in absence of S9 fraction induced not statistically significant decrease in cell viability and significant increase in DNA damage in all cell types at the highest concentrations investigated. However, only SHSY5Y cells showed OA induced genotoxic and cytotoxic effects in presence of S9 fraction. Furthermore, we found that OA can induce modulations in DNA repair processes when exposure was performed prior to BLM treatment, in co-exposure, or during the subsequent DNA repair process. Copyright 2010 Elsevier B.V. All rights reserved.

Hormesis in Cholestatic Liver Disease; Preconditioning with Low Bile Acid Concentrations Protects against Bile Acid-Induced Toxicity

NARCIS (Netherlands)

Verhaag, Esther M.; Buist-Homan, Manon; Koehorst, Martijn; Groen, Albert K.; Moshage, Han; Faber, Klaas Nico

2016-01-01

Cholestasis is characterized by accumulation of bile acids and inflammation, causing hepatocellular damage. Still, liver damage markers are highest in acute cholestasis and drop when this condition becomes chronic, indicating that hepatocytes adapt towards the hostile environment. This may be

Relative binding affinity of carboxylate-, phosphonate-, and bisphosphonate-functionalized gold nanoparticles targeted to damaged bone tissue

Energy Technology Data Exchange (ETDEWEB)

Ross, Ryan D. [Rush University Medical Center, Department of Anatomy and Cell Biology (United States); Cole, Lisa E.; Roeder, Ryan K., E-mail: rroeder@nd.edu [University of Notre Dame, Department of Aerospace and Mechanical Engineering Bioengineering Graduate Program (United States)

2012-10-15

Functionalized Au NPs have received considerable recent interest for targeting and labeling cells and tissues. Damaged bone tissue can be targeted by functionalizing Au NPs with molecules exhibiting affinity for calcium. Therefore, the relative binding affinity of Au NPs surface functionalized with either carboxylate (l-glutamic acid), phosphonate (2-aminoethylphosphonic acid), or bisphosphonate (alendronate) was investigated for targeted labeling of damaged bone tissue in vitro. Targeted labeling of damaged bone tissue was qualitatively verified by visual observation and backscattered electron microscopy, and quantitatively measured by the surface density of Au NPs using field-emission scanning electron microscopy. The surface density of functionalized Au NPs was significantly greater within damaged tissue compared to undamaged tissue for each functional group. Bisphosphonate-functionalized Au NPs exhibited a greater surface density labeling damaged tissue compared to glutamic acid- and phosphonic acid-functionalized Au NPs, which was consistent with the results of previous work comparing the binding affinity of the same functionalized Au NPs to synthetic hydroxyapatite crystals. Targeted labeling was enabled not only by the functional groups but also by the colloidal stability in solution. Functionalized Au NPs were stabilized by the presence of the functional groups, and were shown to remain well dispersed in ionic (phosphate buffered saline) and serum (fetal bovine serum) solutions for up to 1 week. Therefore, the results of this study suggest that bisphosphonate-functionalized Au NPs have potential for targeted delivery to damaged bone tissue in vitro and provide motivation for in vivo investigation.

Is Allelopathic Activity of Ipomoea murucoides Induced by Xylophage Damage?

Science.gov (United States)

Flores-Palacios, Alejandro; Corona-López, Angélica María; Rios, María Yolanda; Aguilar-Guadarrama, Berenice; Toledo-Hernández, Víctor Hugo; Rodríguez-López, Verónica; Valencia-Díaz, Susana

2015-01-01

Herbivory activates the synthesis of allelochemicals that can mediate plant-plant interactions. There is an inverse relationship between the activity of xylophages and the abundance of epiphytes on Ipomoea murucoides. Xylophagy may modify the branch chemical constitution, which also affects the liberation of allelochemicals with defense and allelopathic properties. We evaluated the bark chemical content and the effect of extracts from branches subjected to treatments of exclusion, mechanical damage and the presence/absence of epiphytes, on the seed germination of the epiphyte Tillandsia recurvata. Principal component analysis showed that branches without any treatment separate from branches subjected to treatments; damaged and excluded branches had similar chemical content but we found no evidence to relate intentional damage with allelopathy; however 1-hexadecanol, a defense volatile compound correlated positively with principal component (PC) 1. The chemical constitution of branches subject to exclusion plus damage or plus epiphytes was similar among them. PC2 indicated that palmitic acid (allelopathic compound) and squalene, a triterpene that attracts herbivore enemies, correlated positively with the inhibition of seed germination of T. recurvata. Inhibition of seed germination of T. recurvata was mainly correlated with the increment of palmitic acid and this compound reached higher concentrations in excluded branches treatments. Then, it is likely that the allelopathic response of I. murucoides would increase to the damage (shade, load) that may be caused by a high load of epiphytes than to damage caused by the xylophages.

Is Allelopathic Activity of Ipomoea murucoides Induced by Xylophage Damage?

Directory of Open Access Journals (Sweden)

Alejandro Flores-Palacios

Full Text Available Herbivory activates the synthesis of allelochemicals that can mediate plant-plant interactions. There is an inverse relationship between the activity of xylophages and the abundance of epiphytes on Ipomoea murucoides. Xylophagy may modify the branch chemical constitution, which also affects the liberation of allelochemicals with defense and allelopathic properties. We evaluated the bark chemical content and the effect of extracts from branches subjected to treatments of exclusion, mechanical damage and the presence/absence of epiphytes, on the seed germination of the epiphyte Tillandsia recurvata. Principal component analysis showed that branches without any treatment separate from branches subjected to treatments; damaged and excluded branches had similar chemical content but we found no evidence to relate intentional damage with allelopathy; however 1-hexadecanol, a defense volatile compound correlated positively with principal component (PC 1. The chemical constitution of branches subject to exclusion plus damage or plus epiphytes was similar among them. PC2 indicated that palmitic acid (allelopathic compound and squalene, a triterpene that attracts herbivore enemies, correlated positively with the inhibition of seed germination of T. recurvata. Inhibition of seed germination of T. recurvata was mainly correlated with the increment of palmitic acid and this compound reached higher concentrations in excluded branches treatments. Then, it is likely that the allelopathic response of I. murucoides would increase to the damage (shade, load that may be caused by a high load of epiphytes than to damage caused by the xylophages.

Acidic weathering of carbonate building stones: experimental assessment

Directory of Open Access Journals (Sweden)

Ryszard Kryza

2009-06-01

Full Text Available Three types of carbonate rocks, travertine, limestone and marble have been studied to determine their selected technical parameters (water absorption, resistance to salt crystallization damage and reaction to experimentally modelled acid rain weathering imitating the polluted urban atmospheric conditions. The acidic agents present in natural acid rain precipitation, H2SO4, HCl, HNO3, CH3COOH and mixture of all the acids, “Acid mix”, were tested. The initial stages of acid weathering involve, apart from chemical dissolution, particularly intense physical detachment of rock particles (granular disintegration significantly contributing to the total mass loss. Travertine was found to be most prone to salt crystallization damage and to acid weathering, and these features should be taken into account especially in external architectural usage of this stone in cold climate conditions and polluted urban atmosphere.

Aortic wall damage in mice unable to synthesize ascorbic acid

OpenAIRE

Maeda, Nobuyo; Hagihara, Hiroyuki; Nakata, Yukiko; Hiller, Sylvia; Wilder, Jennifer; Reddick, Robert

2000-01-01

By inactivating the gene for l-gulono-γ-lactone oxidase, a key enzyme in ascorbic acid synthesis, we have generated mice that, like humans, depend on dietary vitamin C. Regular chow, containing about 110 mg/kg of vitamin C, is unable to support the growth of the mutant mice, which require l-ascorbic acid supplemented in their drinking water (330 mg/liter). Upon withdrawal of supplementation, plasma and tissue ascorbic acid levels decreased to 10–15% of normal within 2 weeks, and after 5 weeks...

Lung damage and pulmonary uptake of serotonin in intact dogs

International Nuclear Information System (INIS)

Dawson, C.A.; Christensen, C.W.; Rickaby, D.A.; Linehan, J.H.; Johnston, M.R.

1985-01-01

The authors examined the influence of glass bead embolization and oleic acid, dextran, and imipramine infusion on the pulmonary uptake of trace doses of [ 3 H]serotonin and the extravascular volume accessible to [ 14 C]antipyrine in anesthetized dogs. Embolization and imipramine decreased serotonin uptake by 53 and 61%, respectively, but no change was observed with oleic acid or dextran infusion. The extravascular volume accessible to the antipyrine was reduced by 77% after embolization and increased by 177 and approximately 44% after oleic acid and dextran infusion, respectively. The results suggest that when the perfused endothelial surface is sufficiently reduced, as with embolization, the uptake of trace doses of serotonin will be depressed. In addition, decreases in serotonin uptake in response to imipramine in this study and in response to certain endothelial toxins in other studies suggest that serotonin uptake can reveal certain kinds of changes in endothelial function. However, the lack of a response to oleic acid-induced damage in the present study suggests that serotonin uptake is not sensitive to all forms of endothelial damage

Cells Deficient in the Fanconi Anemia Protein FANCD2 are Hypersensitive to the Cytotoxicity and DNA Damage Induced by Coffee and Caffeic Acid.

Science.gov (United States)

Burgos-Morón, Estefanía; Calderón-Montaño, José Manuel; Orta, Manuel Luis; Guillén-Mancina, Emilio; Mateos, Santiago; López-Lázaro, Miguel

2016-07-08

Epidemiological studies have found a positive association between coffee consumption and a lower risk of cardiovascular disorders, some cancers, diabetes, Parkinson and Alzheimer disease. Coffee consumption, however, has also been linked to an increased risk of developing some types of cancer, including bladder cancer in adults and leukemia in children of mothers who drink coffee during pregnancy. Since cancer is driven by the accumulation of DNA alterations, the ability of the coffee constituent caffeic acid to induce DNA damage in cells may play a role in the carcinogenic potential of this beverage. This carcinogenic potential may be exacerbated in cells with DNA repair defects. People with the genetic disease Fanconi Anemia have DNA repair deficiencies and are predisposed to several cancers, particularly acute myeloid leukemia. Defects in the DNA repair protein Fanconi Anemia D2 (FANCD2) also play an important role in the development of a variety of cancers (e.g., bladder cancer) in people without this genetic disease. This communication shows that cells deficient in FANCD2 are hypersensitive to the cytotoxicity (clonogenic assay) and DNA damage (γ-H2AX and 53BP1 focus assay) induced by caffeic acid and by a commercial lyophilized coffee extract. These data suggest that people with Fanconi Anemia, or healthy people who develop sporadic mutations in FANCD2, may be hypersensitive to the carcinogenic activity of coffee.

Reduction of the DNA damages, Hepatoprotective Effect and Antioxidant Potential of the Coconut Water, ascorbic and Caffeic Acids in Oxidative Stress Mediated by Ethanol

Directory of Open Access Journals (Sweden)

VANDERSON S. BISPO

Full Text Available ABSTRACT Hepatic disorders such as steatosis and alcoholic steatohepatitis are common diseases that affect thousands of people around the globe. This study aims to identify the main phenol compounds using a new HPLC-ESI+-MS/MS method, to evaluate some oxidative stress parameters and the hepatoprotective action of green dwarf coconut water, caffeic and ascorbic acids on the liver and serum of rats treated with ethanol. The results showed five polyphenols in the lyophilized coconut water spiked with standards: chlorogenic acid (0.18 µM, caffeic acid (1.1 µM, methyl caffeate (0.03 µM, quercetin (0.08 µM and ferulic acid (0.02 µM isomers. In the animals, the activity of the serum γ-glutamyltranspeptidase (γ-GT was reduced to 1.8 I.U/L in the coconut water group, 3.6 I.U/L in the ascorbic acid group and 2.9 I.U/L in the caffeic acid groups, when compared with the ethanol group (5.1 I.U/L, p<0.05. Still in liver, the DNA analysis demonstrated a decrease of oxidized bases compared to ethanol group of 36.2% and 48.0% for pretreated and post treated coconut water group respectively, 42.5% for the caffeic acid group, and 34.5% for the ascorbic acid group. The ascorbic acid was efficient in inhibiting the thiobarbituric acid reactive substances (TBARS in the liver by 16.5% in comparison with the ethanol group. These data indicate that the green dwarf coconut water, caffeic and ascorbic acids have antioxidant, hepatoprotective and reduced DNA damage properties, thus decreasing the oxidative stress induced by ethanol metabolism.

Citric acid enhances the phytoextraction of manganese and plant growth by alleviating the ultrastructural damages in Juncus effusus L

Energy Technology Data Exchange (ETDEWEB)

Najeeb, U.; Xu, L.; Ali, Shafaqat [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Jilani, Ghulam, E-mail: jilani@uaar.edu.pk [Department of Soil Science, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Punjab 46300 (Pakistan); Gong, H.J. [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Shen, W.Q. [The University of Nottingham at Ningbo, Ningbo 315100 (China); Zhou, W.J., E-mail: wjzhou@zju.edu.cn [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China)

2009-10-30

Chelate-assisted phytoextraction by high biomass producing plant species enhances the removal of heavy metals from polluted environments. In this regard, Juncus effusus a wetland plant has great potential. This study evaluated the effects of elevated levels of manganese (Mn) on the vegetative growth, Mn uptake and antioxidant enzymes in J. effusus. We also studied the role of citric acid and EDTA on improving metal accumulation, plant growth and Mn toxicity stress alleviation. Three-week-old plantlets of J. effusus were subjected to various treatments in the hydroponics as: Mn (50, 100 and 500 {mu}M) alone, Mn (500 {mu}M) + citric acid (5 mM), and Mn (500 {mu}M) + EDTA (5 mM). After 2 weeks of treatment, higher Mn concentrations significantly reduced the plant biomass and height. Both citric acid and EDTA restored the plant height as it was reduced at the highest Mn level. Only the citric acid (but not EDTA) was able to recover the plant biomass weight, which was also obvious from the microscopic visualization of mesophyll cells. There was a concentration dependent increase in Mn uptake in J. effusus plants, and relatively more deposition in roots compared to aerial parts. Although both EDTA and citric acid caused significant increase in Mn accumulation; however, the Mn translocation was enhanced markedly by EDTA. Elevated levels of Mn augmented the oxidative stress, which was evident from changes in the activities of antioxidative enzymes in plant shoots. Raised levels of lipid peroxidation and variable changes in the activities of antioxidant enzymes were recorded under Mn stress. Electron microscopic images revealed several modifications in the plants at cellular and sub-cellular level due to the oxidative damage induced by Mn. Changes in cell shape and size, chloroplast swelling, increased number of plastoglobuli and disruption of thylakoid were noticed. However, these plants showed a high degree of tolerance against Mn toxicity stress, and it removed

Citric acid enhances the phytoextraction of manganese and plant growth by alleviating the ultrastructural damages in Juncus effusus L

International Nuclear Information System (INIS)

Najeeb, U.; Xu, L.; Ali, Shafaqat; Jilani, Ghulam; Gong, H.J.; Shen, W.Q.; Zhou, W.J.

2009-01-01

Chelate-assisted phytoextraction by high biomass producing plant species enhances the removal of heavy metals from polluted environments. In this regard, Juncus effusus a wetland plant has great potential. This study evaluated the effects of elevated levels of manganese (Mn) on the vegetative growth, Mn uptake and antioxidant enzymes in J. effusus. We also studied the role of citric acid and EDTA on improving metal accumulation, plant growth and Mn toxicity stress alleviation. Three-week-old plantlets of J. effusus were subjected to various treatments in the hydroponics as: Mn (50, 100 and 500 μM) alone, Mn (500 μM) + citric acid (5 mM), and Mn (500 μM) + EDTA (5 mM). After 2 weeks of treatment, higher Mn concentrations significantly reduced the plant biomass and height. Both citric acid and EDTA restored the plant height as it was reduced at the highest Mn level. Only the citric acid (but not EDTA) was able to recover the plant biomass weight, which was also obvious from the microscopic visualization of mesophyll cells. There was a concentration dependent increase in Mn uptake in J. effusus plants, and relatively more deposition in roots compared to aerial parts. Although both EDTA and citric acid caused significant increase in Mn accumulation; however, the Mn translocation was enhanced markedly by EDTA. Elevated levels of Mn augmented the oxidative stress, which was evident from changes in the activities of antioxidative enzymes in plant shoots. Raised levels of lipid peroxidation and variable changes in the activities of antioxidant enzymes were recorded under Mn stress. Electron microscopic images revealed several modifications in the plants at cellular and sub-cellular level due to the oxidative damage induced by Mn. Changes in cell shape and size, chloroplast swelling, increased number of plastoglobuli and disruption of thylakoid were noticed. However, these plants showed a high degree of tolerance against Mn toxicity stress, and it removed substantial

DNA damage by smoke: Protection by turmeric and other inhibitors of ROS

Energy Technology Data Exchange (ETDEWEB)

Srinivas, L.; Shalini, V.K. (Department of Nutrition and Food Safety, Central Food Technological Research Institute, Mysore (India))

1991-01-01

Twigs-dry leaves smoke condensate (TDS), as a source of clastogenic ROS and carcinogenic PAH, was investigated for its in vitro DNA-damaging effect in calf thymus DNA and human peripheral lymphocytes. An aqueous turmeric component--Aq.T--with an established antioxidant activity, was tested as a DNA protectant. TDS induced 13-fold damage to calf thymus DNA as judged by the emergence of a DNA damage specific, fluorescent product (em: 405 nm). Aq.T at 800 ng/microL extended 69% protection to calf thymus DNA and was comparable to the other protectants such as curcumin, BHA, vitamin E, SOD, and CAT. In human peripheral lymphocytes, TDS induced extensive DNA damage in comparison with the tumor promoter TPA, as judged by FADU. Aq.T at 300 ng/microL extended 90% protection to human lymphocyte DNA against TDS-induced damage, and was more effective than the other protectants--DABCO, D-mannitol, sodium benzoate, vitamin E (ROS quenchers), SOD, CAT (antioxidant enzymes), tannic acid, flufenamic acid, BHA, BHT, n-PG, curcumin and quercetin (antioxidants). Aq.T offered 65% protection to human lymphocyte DNA against TPA-induced damage and was comparable to SOD. The above results indicate that TDS induces substantial DNA damage in calf thymus DNA and human lymphocytes and Aq.T is an efficient protectant.

Comparison of four species-delimitation methods applied to a DNA barcode data set of insect larvae for use in routine bioassessment for use in routine bioassessment

Science.gov (United States)

Species delimitation (grouping individuals into distinct taxonomic groups) is an essential part of evolutionary, conservation, and molecular ecology. Deoxyribonucleic acid (DNA) barcodes, short fragments of the cytochrome c oxidase subunit I (COI) gene, are being used in environm...

Fulltext PDF

Indian Academy of Sciences (India)

Unknown

deoxyribonucleic acid. M GOPALa*, M S ... base pairs of DNA and interference with normal functioning of the enzyme topo- isomerase II which ... Data from the fluorescence titrations were used to determine the binding constant of. MPTQ with ...

Effect of uric acid on oxidative damage

Czech Academy of Sciences Publication Activity Database

Buňková, Radka; Papežíková, Ivana; Podborská, Martina; Lojek, Antonín

2007-01-01

Roč. 101, č. 14 (2007), s170-s171 E-ISSN 1213-7103. [Mezioborová česko-slovenská toxikologická konference /12./. Praha, 11.06.2007-13.06.2007] R&D Projects: GA ČR(CZ) GP204/07/P539 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : uric acid * lipid peroxidation * HPLC Subject RIV: BO - Biophysics

Certified reference materials - beech leaves and spruce needles - for the quality control in monitoring damage in forests by acid deposition

Energy Technology Data Exchange (ETDEWEB)

Maier, E A; Griepink, B [Commission of the European Communities, Brussels (Belgium). Community Bureau of Reference; Muntau, H [Commission of the European Communities, Ispra (Italy). Joint Research Centre

1989-12-01

The chemical determination of various elements in leaves or needles allows to establish the damage caused by acid deposition. To control the quality of such determinations the Community Bureau of Reference (BCR) produced two Certified Reference Materials: Beech leaves (CRM No. 100) and Spruce needles (CRM No. 101). After a careful preparation procedure, a homogeneity study and a long term stability study, the materials were certified for: Cl, N, P and S in CRM No. 100, Al, Ca, Cl, Mg, Mn, N, P, S and Zn in CRM No. 101. Indicative values on the content of 19 majors and trace elements are also reported. (orig.).

Lysergic acid diethylamide causes photoreceptor cell damage through inducing inflammatory response and oxidative stress.

Science.gov (United States)

Hu, Qi-Di; Xu, Ling-Li; Gong, Yan; Wu, Guo-Hai; Wang, Yu-Wen; Wu, Shan-Jun; Zhang, Zhe; Mao, Wei; Zhou, Yu-Sheng; Li, Qin-Bo; Yuan, Jian-Shu

2018-01-19

Lysergic acid diethylamide (LSD), a classical hallucinogen, was used as a popular and notorious substance of abuse in various parts of the world. Its abuse could result in long-lasting abnormalities in retina and little is known about the exact mechanism. This study was to investigate the effect of LSD on macrophage activation state at non-toxic concentration and its resultant toxicity to photoreceptor cells. Results showed that cytotoxicity was caused by LSD on 661 W cells after co-culturing with RAW264.7 cells. Treatment with LSD-induced RAW264.7 cells to the M1 phenotype, releasing more pro-inflammatory cytokines, and increasing the M1-related gene expression. Moreover, after co-culturing with RAW264.7 cells, significant oxidative stress in 661 W cells treated with LSD was observed, by increasing the level of malondialdehyde (MDA) and reactive oxygen species (ROS), and decreasing the level of glutathione (GSH) and the activity of superoxide dismutase (SOD). Our study demonstrated that LSD caused photoreceptor cell damage by inducing inflammatory response and resultant oxidative stress, providing the scientific rationale for the toxicity of LSD to retina.

DNA Damage Protecting Activity and Antioxidant Potential of Launaea taraxacifolia Leaves Extract.

Science.gov (United States)

Adinortey, Michael Buenor; Ansah, Charles; Weremfo, Alexander; Adinortey, Cynthia Ayefoumi; Adukpo, Genevieve Etornam; Ameyaw, Elvis Ofori; Nyarko, Alexander Kwadwo

2018-01-01

The leaf extract of Launaea taraxacifolia commonly known as African Lettuce is used locally to treat dyslipidemia and liver diseases, which are associated with oxidative stress. Methanol extract from L. taraxacifolia leaves was tested for its antioxidant activity and its ability to protect DNA from oxidative damage. In vitro antioxidant potential of the leaf extract was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO), and hydroxyl (OH) radical scavenging assays. Ferric reducing power, total antioxidant capacity (TAC), metal chelating, and anti-lipid peroxidation ability of the extract were also examined using gallic acid, ascorbic acid, citric acid, and ethylenediaminetetraacetic acid as standards. L. taraxacifolia leaves extract showed antioxidant activity with IC 50 values of 16.18 μg/ml (DPPH), 123.3 μg/ml (NO), 128.2 μg/ml (OH radical), 97.94 μg/ml (metal chelating), 80.28 μg/ml (TAC), and 23 μg/ml (anti-lipid peroxidation activity). L. taraxacifolia leaves extract exhibited a strong capability for DNA damage protection at 20 mg/ml concentration. These findings suggest that the methanolic leaf extract of L. taraxacifolia could be used as a natural antioxidant and also as a preventive therapy against diseases such as arteriosclerosis associated with DNA damage.

Toxicity of nalidixic acid on candida albicans, Saccharomyces cerevisiae, and Kluyveromyces lactis.

Science.gov (United States)

Sobieski, R J; Brewer, A R

1976-03-01

The antibacterial drug nalidixic acid (Nal) can suppress the growth of Candida albicans at levels of the drug normally found in urine. Growth suppression increases as drug levels are increased, and Nal also causes a similar proportional inhibition of the synthesis of all cellular macromolecules. However, growth temperature (25 versus 37 C) and the divalent cations Mg(2+) and Mn(2+) can increase C. albicans resistance to Nal. Also, nitrogen depletion of Candida shows that Nal-treated and untreated cells exhibit no difference in leucine uptake during readaptation to nitrogen. In Nal-treated, nitrogen-starved cells, ribonucleic acid and deoxyribonucleic acid (DNA) biosynthesis are less affected than in unstarved Nal-treated cells, but of the two nucleic acids DNA synthesis is the most affected. Nal-resistant strains of C. albicans exhibit a slight toxicity for macromolecular synthesis. Nal treatment of a synchronized population of Saccharomyces cerevisiae results in an increase in the culture mean doubling time of, at most, 20%, but Nal causes the loss of synchronous cell division. With a synchronized population of Kluyveromyces lactis, Nal causes an increase in the mean doubling time of upwards of 300%, with synchrony of cell division being maintained. It is known that S. cerevisiae asynchronously synthesizes mitochondrial DNA during the cell cycle, whereas with K. lactis it is synchronous. Thus, with C. albicans Nal toxicity is dependent both on the dose and the physiological state of the cell. Furthermore, Nal inhibits growth of yeast with synchronous mitochondrial DNA synthesis more adversely than yeast with asynchronous mitochondrial DNA synthesis.

Acidification and Acid Rain

Science.gov (United States)

Norton, S. A.; Veselã½, J.

2003-12-01

endangers the existing biota. Concerns about acid (or acidic) rain in its modern sense were publicized by the Swedish soil scientist Svante Odén (1968). He argued, initially in the Swedish press, that long-term increases in the atmospheric deposition of acid could lower the pH of surface waters, cause a decline in fish stocks, deplete soils of nutrients, and accelerate damage to materials. By the 1970s, acidification of surface waters was reported in many countries in Europe as well as in North America. The late twentieth-century rush to understand the impact of acid rain was driven by: (i) reports of damaged or threatened freshwater fisheries and (ii) damaged forests. Perhaps the earliest linkage between acidic surface water and damage to fish was made by Dahl (1921) in southern Norway. There, spring runoff was sufficiently acidic to kill trout. It was not until the 1970s that a strong link was established between depressed pH, mobilization of aluminum from soil, and fish status ( Schofield and Trojnar,1980). The relationship between acidification of soils and forest health started with hypotheses in the 1960s and has slowly developed. Acid rain enhances the availability of some nutrients (e.g., nitrogen), and may either enhance or diminish the availability of others (e.g., calcium, magnesium, potassium, and phosphorus). Damage to anthropogenic structures, human health, and visibility have also raised concerns. The history of these early developments was summarized by Cowling (1982). Since the 1970s, sulfur and nitrogen emissions to the atmosphere have been reduced by 50-85% and 0-30%, respectively, both in North America and Europe. The emission reductions have occurred as a consequence of knowledge gained and economic factors. While recovery of water quality is underway in some areas, problems of acidification persist, and are now complicated by the effects of climate change ( Schindler, 1997).

Iodine-125 induced DNA strand breakage: Contributions of different physical and chemical radiation action mechanisms

International Nuclear Information System (INIS)

Li, W.

2002-01-01

The decay of the radioisotope 125 I into 125 Te is typically followed by the emission of two groups of approximately 10 electrons each. In deoxyribonucleic acid (DNA) with 125 I incorporated, these electrons produce various types of damage to DNA, e.g. single and double strand breaks. They occur through direct actions of physical tracks, or indirect actions of radicals produced in water. Among the direct actions one should consider not only the excitation and ionization of DNA by electrons but also the neutralization of highly charged 125m Te ions with electrons from neighboring molecules. The present work begins with a detailed description of electron tracks with the use of the PARTRAC code, compares results with recent experiments, and concludes with a firm assessment of the contribution to the strand break yields from the neutralization effect. (orig.)

Electrostatic stiffening and induced persistence length for coassembled molecular bottlebrushes

NARCIS (Netherlands)

Storm, Ingeborg M.; Stuart, Martien A.C.; Vries, de Renko; Leermakers, Frans A.M.

2018-01-01

A self-consistent field analysis for tunable contributions to the persistence length of isolated semiflexible polymer chains including electrostatically driven coassembled deoxyribonucleic acid (DNA) bottlebrushes is presented. When a chain is charged, i.e., for polyelectrolytes, there is, in

Promotion and inhibition of mutation in pathogens

Directory of Open Access Journals (Sweden)

Maurice Samuel Devaraj

2014-03-01

Findings from this research may be used to prevent development of drug resistance, whether epigenetic or arising due to deoxyribonucleic acid (DNA modification, in several pathogens, especially Mycobacterium tuberculosis through the co-administration of adenosine along with antibiotic treatment.

Oxidatively generated DNA/RNA damage in psychological stress states

DEFF Research Database (Denmark)

Jørgensen, Anders

2013-01-01

age-related somatic disorders. The overall aim of the PhD project was to investigate the relation between psychopathology, psychological stress, stress hormone secretion and oxidatively generated DNA and RNA damage, as measured by the urinary excretion of markers of whole-body DNA/RNA oxidation (8...... between the 24 h urinary cortisol excretion and the excretion of 8-oxodG/8-oxoGuo, determined in the same samples. Collectively, the studies could not confirm an association between psychological stress and oxidative stress on nucleic acids. Systemic oxidatively generated DNA/RNA damage was increased......Both non-pathological psychological stress states and mental disorders are associated with molecular, cellular and epidemiological signs of accelerated aging. Oxidative stress on nucleic acids is a critical component of cellular and organismal aging, and a suggested pathogenic mechanism in several...

Complexation and molecular modeling studies of europium(III)-gallic acid-amino acid complexes.

Science.gov (United States)

Taha, Mohamed; Khan, Imran; Coutinho, João A P

2016-04-01

With many metal-based drugs extensively used today in the treatment of cancer, attention has focused on the development of new coordination compounds with antitumor activity with europium(III) complexes recently introduced as novel anticancer drugs. The aim of this work is to design new Eu(III) complexes with gallic acid, an antioxida'nt phenolic compound. Gallic acid was chosen because it shows anticancer activity without harming health cells. As antioxidant, it helps to protect human cells against oxidative damage that implicated in DNA damage, cancer, and accelerated cell aging. In this work, the formation of binary and ternary complexes of Eu(III) with gallic acid, primary ligand, and amino acids alanine, leucine, isoleucine, and tryptophan was studied by glass electrode potentiometry in aqueous solution containing 0.1M NaNO3 at (298.2 ± 0.1) K. Their overall stability constants were evaluated and the concentration distributions of the complex species in solution were calculated. The protonation constants of gallic acid and amino acids were also determined at our experimental conditions and compared with those predicted by using conductor-like screening model for realistic solvation (COSMO-RS) model. The geometries of Eu(III)-gallic acid complexes were characterized by the density functional theory (DFT). The spectroscopic UV-visible and photoluminescence measurements are carried out to confirm the formation of Eu(III)-gallic acid complexes in aqueous solutions. Copyright © 2016 Elsevier Inc. All rights reserved.

Aortic wall damage in mice unable to synthesize ascorbic acid.

Science.gov (United States)

Maeda, N; Hagihara, H; Nakata, Y; Hiller, S; Wilder, J; Reddick, R

2000-01-18

By inactivating the gene for L-gulono-gamma-lactone oxidase, a key enzyme in ascorbic acid synthesis, we have generated mice that, like humans, depend on dietary vitamin C. Regular chow, containing about 110 mg/kg of vitamin C, is unable to support the growth of the mutant mice, which require L-ascorbic acid supplemented in their drinking water (330 mg/liter). Upon withdrawal of supplementation, plasma and tissue ascorbic acid levels decreased to 10-15% of normal within 2 weeks, and after 5 weeks the mutants became anemic, began to lose weight, and die. Plasma total antioxidative capacities were approximately 37% normal in homozygotes after feeding the unsupplemented diet for 3-5 weeks. As plasma ascorbic acid decreased, small, but significant, increases in total cholesterol and decreases in high density lipoprotein cholesterol were observed. The most striking effects of the marginal dietary vitamin C were alterations in the wall of aorta, evidenced by the disruption of elastic laminae, smooth muscle cell proliferation, and focal endothelial desquamation of the luminal surface. Thus, marginal vitamin C deficiency affects the vascular integrity of mice unable to synthesize ascorbic acid, with potentially profound effects on the pathogenesis of vascular diseases. Breeding the vitamin C-dependent mice with mice carrying defined genetic mutations will provide numerous opportunities for systematic studies of the role of antioxidants in health and disease.

MOLECULAR EVALUATION OF CHANGES IN PLANKTONIC BACTERIAL POPULATIONS RESULTING FROM EQUINE FECAL CONTAMINATION IN A SUB-WATERSHED

Science.gov (United States)

Considerable emphasis has been placed on developing watershed-based strategies with the potential to reduce non-point-source fecal contamination. Molecular methods applied used 16S-ribosomal-deoxyribonucleic-acid (rDNA) to try to determine sources of fecal contamination. Objectiv...

Viruses of the Archaea

DEFF Research Database (Denmark)

Basta, T.; Garrett, Roger Antony; Prangishvili,, David

2009-01-01

Double-stranded deoxyribonucleic acid (DNA) viruses that infect members of the third domain of life, the Archaea, are diverse and exceptional in both their morphotypes and their genomic properties. The majority of characterized species infect hyperthermophilic hosts and carry morphological featur...

Fatty acid-amino acid conjugates are essential for systemic activation of salicylic acid-induced protein kinase and accumulation of jasmonic acid in Nicotiana attenuata.

Science.gov (United States)

Hettenhausen, Christian; Heinrich, Maria; Baldwin, Ian T; Wu, Jianqiang

2014-11-28

Herbivory induces the activation of mitogen-activated protein kinases (MAPKs), the accumulation of jasmonates and defensive metabolites in damaged leaves and in distal undamaged leaves. Previous studies mainly focused on individual responses and a limited number of systemic leaves, and more research is needed for a better understanding of how different plant parts respond to herbivory. In the wild tobacco Nicotiana attenuata, FACs (fatty acid-amino acid conjugates) in Manduca sexta oral secretions (OS) are the major elicitors that induce herbivory-specific signaling but their role in systemic signaling is largely unknown. Here, we show that simulated herbivory (adding M. sexta OS to fresh wounds) dramatically increased SIPK (salicylic acid-induced protein kinase) activity and jasmonic acid (JA) levels in damaged leaves and in certain (but not all) undamaged systemic leaves, whereas wounding alone had no detectable systemic effects; importantly, FACs and wounding are both required for activating these systemic responses. In contrast to the activation of SIPK and elevation of JA in specific systemic leaves, increases in the activity of an important anti-herbivore defense, trypsin proteinase inhibitor (TPI), were observed in all systemic leaves after simulated herbivory, suggesting that systemic TPI induction does not require SIPK activation and JA increases. Leaf ablation experiments demonstrated that within 10 minutes after simulated herbivory, a signal (or signals) was produced and transported out of the treated leaves, and subsequently activated systemic responses. Our results reveal that N. attenuata specifically recognizes herbivore-derived FACs in damaged leaves and rapidly send out a long-distance signal to phylotactically connected leaves to activate MAPK and JA signaling, and we propose that FACs that penetrated into wounds rapidly induce the production of another long-distance signal(s) which travels to all systemic leaves and activates TPI defense.

The prevention of radiation-induced DNA damage and apoptosis in human intestinal epithelial cells by salvianic acid A

Directory of Open Access Journals (Sweden)

Yanjun Zhang

2014-07-01

Full Text Available The topic of radiation always provokes public debate, and the uses of radiation for therapeutic and other purposes have always been associated with some anxiety. Salvia miltiorrhiza Bunge has been widely used for the treatment of various diseases including cerebrovascular diseases, coronary artery diseases, and myocardial infarction. Salvianolic acid A (SAA d (+-(3,4-dihydroxyphenyl lactic acid is the principal effective, watersoluble constituent of Salvia miltiorrhiza Bunge. In our present study, radiation-induced DNA damage and apoptosis in human intestinal epithelial cells (HIEC in the presence and absence of SAA were examined. We investigated the effects of SAA on ROS formation and the activity of enzymatic antioxidants (SOD, the lipid peroxidative index and the levels of non-enzymatic antioxidant (GSH. Finally, we investigated whether the reduction of radiation-induced cell death caused by SAA might be related to mitochondria-dependent apoptosis. Present findings indicate that SAA is a promising radioprotective agent with a strong antioxidant activity. SAA exerted its protective action on the proliferative activity of HIEC cells as evidenced by decreased cytotoxicity after exposure to γ-radiation. It is possible that SAA achieved its radioprotective action, at least in part, by enhancing DNA repair and the activity of antioxidant enzymes, by scavenging ROS and by inhibiting the mitochondria-dependent apoptotic pathway.

Effect of loperamide and delay of bowel motility on bile acid malabsorption caused by late radiation damage and ileal resection

Energy Technology Data Exchange (ETDEWEB)

Valdes Olmos, R. (Nederlands Kanker Inst., Amsterdam (Netherlands). Dept. of Nuclear Medicine); Hartog Jager, F. den; Hoefnagel, C.; Taal, B. (Nederlands Kanker Inst., Amsterdam (Netherlands). Dept. of Gastroenterology)

1991-05-01

Selenium-75 homocholic acid conjugated with taurine ({sup 75}Se-HCAT) was used during loperamide administration in seven patients suspected of having bile acid malabsorption due to late radiation damage and small-bowel resection in order to document the aetiology of ileal dysfunction and to adjust therapeutic mamagement. In two patients with ileal resection up to 50 cm and in one patient without resection, a reduction of bowel motility by loperamide resulted in marked normalization of the {sup 75}Se-HCAT retention measurements. Sequential scintigraphic {sup 75}Se-HCAT imaging demonstrated a significant improvement in the {sup 75}Se-HCAT reabsorption and recirculation, accompanied in one case by prolongation of colonic retention of the radiopharmaceutical. In four patients with more than 80 cm resection, the {sup 75}Se-HCAT test was abnormal during loperamide administration. In two of these patients for whom baseline values were available, no improvement in the pattern of {sup 75}Se-HCAT absorption was observed. In conclusion, the first results of loperamide {sup 75}Se-HCAT in patients suspected of having bile acid malabsorption and abnormal baseline {sup 75}Se-HCAT are promising. Intervention with loperamide is easy and seems to improve the clinical value of the test with direct therapeutic implications. Sequential {sup 75}Se-HCAT imaging is essential for interpreting changes in the {sup 75}Se-HCAT retention measurements. (orig.).

The effect of gamma irradiation on the nucleic acids content of the mediterranean fruit fly ceratitis capitata (Wied)

International Nuclear Information System (INIS)

Fadel, A.M.; Amin, T.R.; Al-Elimi, M.H.

1999-01-01

This work was carried out study the effect of gamma irradiation on the deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) content in the whole body homogenate of the mediterranean fruit fly, ceratitis capitata (Wied.) pupae were gamma irradiated with different doses (o, 50, 70, 90 and 110 Gy) at two different pupal ages (2 and 4 days before adult emergence ) to estimate the nucleic acids in pupae and adult males, and females. Experimental results showed that gamma irradiation of pupae reduced RNA content, and this reduction was proportional with the applied dose and more pronounced in the younger pupae. However, DNA content was reduced only when the highest dose was applied to pupae irradiated 2 days before adult emergence (older pupae). Concerning adult insects which were gamma irradiated as pupae, the results revealed, generally, that males and females which were irradiated 2 days before adult emergence were more affected than those irradiated 4 days before adult emergence. The male DNA content and the female RNA content showed high degrees of reduction which, more or less, increased with increasing the dose used. On the other hand, female DNA and male RNA contents were slightly, changed. The significant importance of the results and some statistical interrelations were discussed

Crystal structures of B-DNA dodecamer containing the epigenetic modifications 5-hydroxymethylcytosine or 5-methylcytosine

Czech Academy of Sciences Publication Activity Database

Renčiuk, Daniel; Blacque, O.; Vorlíčková, Michaela; Spingler, B.

2013-01-01

Roč. 41, č. 21 (2013), s. 9891-9900 ISSN 0305-1048 R&D Projects: GA ČR GAP205/12/0466; GA MŠk(CZ) ED1.1.00/02.0068 Institutional research plan: CEZ:AV0Z50040702 Institutional support: RVO:68081707 Keywords : NUCLEIC-ACID STRUCTURES * CIRCULAR-DICHROISM * DEOXYRIBONUCLEIC-ACID Subject RIV: BO - Biophysics Impact factor: 8.808, year: 2013

The influence of bile acids homeostasis by cryptotanshinone ...

African Journals Online (AJOL)

The homeostasis of bile acids can be tightly regulated through feed-back and feed-forward regula- tion pathways. Bile acids exert their toxicity towards cells at high concentrations, and the accumulation of bile acids can induce the severe damage towards liver cells 2. Bile acids have been reported to induce cell injury.

Urinary excretion of biomarkers of oxidatively damaged DNA and RNA in hereditary hemochromatosis

DEFF Research Database (Denmark)

Broedbaek, Kasper; Poulsen, Henrik E; Weimann, Allan

2009-01-01

Oxidatively generated damage to nucleic acids is considered to play a significant role in carcinogenesis, and it has been shown that people with hereditary hemochromatosis are at increased risk of cancer. In this study we used a new refined liquid chromatography-tandem mass spectrometry method...... of the iron overload seen in this disease. By this mechanism cellular damage resulting in end organ damage, typically seen in the liver of such patients, may be mediated....

Acid Mine Drainage Treatment

National Research Council Canada - National Science Library

Fripp, Jon

2000-01-01

.... Acid mine drainage (AMD) can have severe impacts to aquatic resources, can stunt terrestrial plant growth and harm wetlands, contaminate groundwater, raise water treatment costs, and damage concrete and metal structures...

Wickerhamiella van der Walt (1973)

Science.gov (United States)

This chapter describes the ascomycetous yeast genus Wickerhamiella, which has five described species and has been defined from multigene deoxyribonucleic acid (DNA) sequence analysis. The species reproduce by multilateral budding but do not form hyphae or pseudohyphae. Asci typically form a single a...

Spatial variation of bacterial community composition near the Luzon ...

African Journals Online (AJOL)

Spatial variation of bacterial community composition near the Luzon strait assessed by polymerase chain reaction-denaturing gradient gel electrophoresis ... chain reaction (PCR)-amplified bacterial 16S ribosomal deoxyribonucleic acid (DNA) gene fragments and interpreted the results; its relationship with physical and ...

How SNP chips will advance our knowledge of factors controlling puberty and aid in selecting replacement females

Science.gov (United States)

The promise of genomic selection is that genetic potential can be accurately predicted from genotypes. Simple deoxyribonucleic acid (DNA) tests might replace low accuracy predictions based on performance and pedigree for expensive or lowly heritable measures of puberty and fertility. The promise i...

Increase of radiation damage to potassium-ion permeability in E. coli cells with decrease in membrane fluidity

International Nuclear Information System (INIS)

Suzuki, S.

1980-01-01

Membrane lipids of an auxotroph of E. coli requiring unsaturated fatty acid were manipulated by supplementing the growth medium with unsaturated fatty acids of different chain lengths and/or configurations, and the radiation damage to K + -permeability of the resulting modified cells was investigated in relation with factors influencing membrane fluidity, such as temperature and procaine. Radiation had greater effects on membranes supplemented with unsaturated fatty acids of the trans configuration with a longer chain than on those of the cis configuration with a shorter chain. Radiation damage also increased with decrease in temperature. Furthermore, procaine-treated membranes showed increased resistance to radiation. All these results indicate that the damage was affected by the physical character of membrane lipids and that it was greater in membranes with decreased fluidity. (author)

Cancer prevention, the need to preserve the integrity of the genome at all cost.

Science.gov (United States)

Okafor, M T; Nwagha, T U; Anusiem, C; Okoli, U A; Nubila, N I; Al-Alloosh, F; Udenyia, I J

2018-05-01

The entire genetic information carried by an organism makes up its genome. Genes have a diverse number of functions. They code different proteins for normal proliferation of cells. However, changes in the base sequence of genes affect their protein by-products which act as messengers for normal cellular functions such as proliferation and repairs. Salient processes for maintaining the integrity of the genome are hinged on intricate mechanisms put in place for the evolution to tackle genomic stresses. To discuss how cells sense and repair damage to their deoxyribonucleic acid (DNA) as well as to highlight how defects in the genes involved in DNA repair contribute to cancer development. Methodology: Online searches on the following databases such as Google Scholar, PubMed, Biomed Central, and SciELO were done. Attempt was made to review articles with keywords such as cancer, cell cycle, tumor suppressor genes, and DNA repair. The cell cycle, tumor suppression genes, DNA repair mechanism, as well as their contribution to cancer development, were discussed and reviewed. Knowledge on how cells detect and repair DNA damage through an array of mechanisms should allay our anxiety as regards cancer development. More studies on DNA damage detection and repair processes are important toward a holistic approach to cancer treatment.

Radiation damage prediction system using damage function

International Nuclear Information System (INIS)

Tanaka, Yoshihisa; Mori, Seiji

1979-01-01

The irradiation damage analysis system using a damage function was investigated. This irradiation damage analysis system consists of the following three processes, the unfolding of a damage function, the calculation of the neutron flux spectrum of the object of damage analysis and the estimation of irradiation effect of the object of damage analysis. The damage function is calculated by applying the SAND-2 code. The ANISN and DOT3, 5 codes are used to calculate neutron flux. The neutron radiation and the allowable time of reactor operation can be estimated based on these calculations of the damage function and neutron flux. The flow diagram of the process of analyzing irradiation damage by a damage function and the flow diagram of SAND-2 code are presented, and the analytical code for estimating damage, which is determined with a damage function and a neutron spectrum, is explained. The application of the irradiation damage analysis system using a damage function was carried out to the core support structure of a fast breeder reactor for the damage estimation and the uncertainty evaluation. The fundamental analytical conditions and the analytical model for this work are presented, then the irradiation data for SUS304, the initial estimated values of a damage function, the error analysis for a damage function and the analytical results are explained concerning the computation of a damage function for 10% total elongation. Concerning the damage estimation of FBR core support structure, the standard and lower limiting values of damage, the permissible neutron flux and the allowable years of reactor operation are presented and were evaluated. (Nakai, Y.)

Heart-type fatty acid binding protein is an early marker of myocardial damage after radiofrequency catheter ablation.

Science.gov (United States)

Giannessi, Daniela; Piacenti, Marcello; Maltinti, Maristella; Rossi, Andrea; Di Cecco, Pietro; Startari, Umberto; Cabiati, Manuela; Panchetti, Luca; Del Ry, Silvia; Morales, Maria-Aurora

2010-10-01

Radiofrequency (RF) ablation of arrhythmias induces myocardial damage and release of biomarkers. This study aimed to assess the kinetics of heart-type fatty acid-binding protein (h-FABP), a cytosolic protein released after myocardial injury incurred by both atrial and ventricular RF ablation, compared to other markers of myocardial injury. h-FABP, cTnI, CK-MB(mass) and myoglobin were evaluated in 30 patients with atrial or ventricular tachyarrhythmias before, immediately after and at 3, 6 and 24h after the procedure. h-FABP increased immediately after the procedure in all subjects (6.6 ± 1.2 μg/L vs 2.7 ± 0.3, pvalues of time for mean power of RF application in both the entire patient cohort and in ventricular ablations. h-FABP may be an early parameter for monitoring RF-induced lesions and the site of ablation was relevant for biomarker increase. Copyright © 2010 Elsevier Inc. All rights reserved.

Evaluation of Single Nucleotide Polymorphisms (SNPs) in the p53 Binding Protein 1 (TP53BP1) Gene in Breast Cancer Patients Treated With Breast-Conserving Surgery and Whole-Breast Irradiation (BCS + RT)

International Nuclear Information System (INIS)

Haffty, Bruce G.; Goyal, Sharad; Kulkarni, Diptee; Green, Camille; Vazquez, Alexi; Schiff, Devora; Moran, Meena S.; Yang Qifeng; Ganesan, Shridar; Hirsfield, Kim M.

2011-01-01

Purpose: TP53BP1 is a key component of radiation-induced deoxyribonucleic acid damage repair. The purpose of this study was to evaluate the significance of a known common single nucleotide polymorphism in this gene (rs560191) in patients treated with breast-conserving surgery and whole-breast irradiation (BCS + RT). Methods and Materials: The population consisted of 176 premenopausal women treated with BCS + RT (median follow-up, 12 years). Genomic deoxyribonucleic acid was processed by use of TaqMan assays. Each allele for rs560191 was either C or G, so each patient was therefore classified as CC, CG, or GG. Patients were grouped as GG if they were homozygous for the variant G allele or CC-CG if they carried at least one copy of the common C allele (CC or CG). Results: Of the 176 women, 124 (71%) were CC-CG and 52 (29%) were GG. The mean age was 44 years for GG vs. 38 years for CC-CG (p < 0.001). GG was more common in African-American women than white women (69% vs. 13%, p < 0.001) and more commonly estrogen receptor negative (70% vs. 49%, p = 0.02). There were no significant correlations of rs560191 with other critical variables. Despite the fact that GG patients were older, the 10-year rate of local relapses was higher (22% for GG vs. 12% for CC-CG, p = 0.04). Conclusions: This novel avenue of investigation of polymorphisms in radiation repair/response genes in patients treated with BCS + RT suggests a correlation to local relapse. Additional evaluation is needed to assess the biological and functional significance of these single nucleotide polymorphisms, and larger confirmatory validation studies will be required to determine the clinical implications.

Role of Omega 3 fatty acids on radiation-induced oxidative and structural damage in different tissues of male albino rats

International Nuclear Information System (INIS)

Rezk, R.G.; Abou Zaid, N.M.; Ahmed, A. G.

2011-01-01

Omega-3 fatty acids play a critical role in the development and function of the reproductive and central nervous systems. The aim of this study is to evaluate the effect of omega-3 fatty acids supplementation on lipid peroxidation and antioxidant enzyme levels associated with histopathologic changes induced by gamma irradiation in the testis and brain of male albino rats. Rats were whole body exposed to radiation at a single dose of 3 Gy. Omega-3 fatty acids (0.4 gm/kg b wt/day) were given to rats, by gavages, for 15 consecutive days before irradiation and for 15 days after irradiation. Rats were sacrificed one and 15 days post irradiation .Biochemical analysis of testis and cerebral cortex samples showed that irradiation induced a significant increase in xanthine oxidase (XO) activity and lipid peroxidation end product malondialdehyde (MDA) and a decrease in the content of reduced glutathione (GSH) and activity of antioxidant enzymes; glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT).Histological examination of testis and cerebral cortex tissues showed spermatogonia degeneration, apoptosis and necrosis in the testis and neurons cell bodies with ill defined and even ruptured cell membrane and damaged blood capillaries in the cerebral cortex. Omega-3 administration has attenuated the toxic effects of radiation by decreasing the levels of MDA, and XO, and increasing the activity of endogenous antioxidant enzymes, which was associated with amelioration of the histological injury markers in both testis and cerebral cortex. It could be postulated that omega-3 fatty acids as a multi-functional dietary supplement could exert a modulatory role in radiation- induced testis and cerebral cortex biochemical and histological changes through its antioxidant properties.

Potential advantages of DNA methyltransferase 1 (DNMT1)-targeted inhibition for cancer therapy.

Science.gov (United States)

Jung, Yeonjoo; Park, Jinah; Kim, Tai Young; Park, Jung-Hyun; Jong, Hyun-Soon; Im, Seock-Ah; Robertson, Keith D; Bang, Yung-Jue; Kim, Tae-You

2007-10-01

The deoxyribonucleic acid (DNA) methyltransferase (DNMT) inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) has been used as a drug in a part of cancer therapy. However, because of its incorporation into DNA during DNA synthesis, 5-aza-dC can cause DNA damage, mutagenesis, and cytotoxicity. In view of the adverse effects of 5-aza-dC, DNMT-targeted inhibition may be a more effective approach than treatment with 5-aza-dC. To address the possibility of DNMT-targeted cancer therapy, we compared the effects of treatment with small interfering ribonucleic acids (siRNAs) specific for DNMT1 or DNMT3b and treatment with 5-aza-dC on transcription, cell growth, and DNA damage in gastric cancer cells. We found that DNMT1-targeted inhibition induced the re-expression and reversed DNA methylation of five (CDKN2A, RASSF1A, HTLF, RUNX3, and AKAP12B) out of seven genes examined, and 5-aza-dC reactivated and demethylated all seven genes. In contrast, DNMT3b siRNAs did not show any effect. Furthermore, the double knockdown of DNMT1 and DNMT3b did not show a synergistic effect on gene re-expression and demethylation. In addition, DNMT1 siRNAs showed an inhibitory effect of cell proliferation in the cancer cells and the induction of cell death without evidence of DNA damage, whereas treatment with 5-aza-dC caused DNA damage as demonstrated by the comet assay. These results provide a rationale for the development of a DNMT1-targeted strategy as an effective epigenetic cancer therapy.

The Effects of α-Lipoic Acid against Testicular Ischemia-Reperfusion Injury in Rats

Directory of Open Access Journals (Sweden)

Seda Ozbal

2012-01-01

Full Text Available Testicular torsion is one of the urologic emergencies occurring frequently in neonatal and adolescent period. Testis is sensitive to ischemia-reperfusion injury, and, therefore, ischemia and consecutive reperfusion cause an enhanced formation of reactive oxygen species that result in testicular cell damage and apoptosis. α-lipoic acid is a free radical scavenger and a biological antioxidant. It is widely used in the prevention of oxidative stress and cellular damage. We aimed to investigate the protective effect of α-lipoic acid on testicular damage in rats subjected to testicular ischemia-reperfusion injury. 35 rats were randomly divided into 5 groups: control, sham operated, ischemia, ischemia-reperfusion, and ischemia-reperfusion +lipoic acid groups, 2 h torsion and 2 h detorsion of the testis were performed. Testicular cell damage was examined by H-E staining. TUNEL and active caspase-3 immunostaining were used to detect germ cell apoptosis. GPx , SOD activity, and MDA levels were evaluated. Histological evaluation showed that α-lipoic acid pretreatment reduced testicular cell damage and decreased TUNEL and caspase-3-positive cells. Additionally, α-lipoic acid administration decreased the GPx and SOD activity and increased the MDA levels. The present results suggest that LA is a potentially beneficial agent in protecting testicular I/R in rats.

Experience with leaf analysis in smoke damage tests

Energy Technology Data Exchange (ETDEWEB)

Garber, K

1960-01-01

The role of chemical analysis in examining plant material for damage caused by smoke is discussed. Most difficult is the diagnosis of SO/sub 2/ damage, even in case of leaf discoloration, because this symptom is not specific. An increased content of sulfur in leaves can be an indication of damage by SO/sub 2/ but this proof is not reliable, since plants can manifest elevated sulfur levels through intake from the soil. A quantitative micromethod for the detection of SO/sub 2/ in fresh leaves has been developed by G. Bredemann and H. Radeloff. Hydrochloric acid and chlorine can also be detected by a micromethod (AgNO/sub 3/) but there is no proof of damage because the natural chloride content in plants fluctuates widely. The same holds for NO/sub 2/ and NO/sub 3/. Ammonia can be detected microchemically with great reliability; fluorine can also be detected microchemically and positive tests usually indicate reliably the cause of damage, but the fluorine test is not always reliable. A microchemical test also exists for asphalt and tar vapors. Thus, if the circumstances of the damage and local conditions are known, microchemical leaf analysis is useful as an auxiliary method in attributing damage to a specific agent. But leaf analysis by itself does not constitute conclusive proof. 12 references.

Opioid Receptors Blockade Modulates Apoptosis in a Rat Model of ...

African Journals Online (AJOL)

inflammation characterized by replacement of liver tissue by ... Materials and Methods: Cirrhosis was induced in rats by bile duct ligation .... treated with deoxyribonucleic acid labeling solution containing ... binding was inhibited using non-immune serum. .... studies considering the increased level of tumor necrosis factor-α.

Protein Structure-sensitive Analysis by Normal Pulse Voltammetry

Czech Academy of Sciences Publication Activity Database

Černocká, Hana; Paleček, Emil

2016-01-01

Roč. 28, č. 11 (2016), s. 2884-2889 ISSN 1040-0397 R&D Projects: GA ČR(CZ) GA15-15479S Institutional support: RVO:68081707 Keywords : mercury -electrodes * deoxyribonucleic-acid * hydrogen evolution Subject RIV: BO - Biophysics Impact factor: 2.851, year: 2016

New aids for the non-invasive prenatal diagnosis of achondroplasia: dysmorphic features, charts of fetal size and molecular confirmation using cell-free fetal DNA in maternal plasma

NARCIS (Netherlands)

Chitty, L. S.; Griffin, D. R.; Meaney, C.; Barrett, A.; Khalil, A.; Pajkrt, E.; Cole, T. J.

2011-01-01

To improve the prenatal diagnosis of achondroplasia by constructing charts of fetal size, defining frequency of sonographic features and exploring the role of non-invasive molecular diagnosis based on cell-free fetal deoxyribonucleic acid (DNA) in maternal plasma. Data on fetuses with a confirmed

Extent of digestion affects the success of amplifying human DNA from blood meals of Anopheles gambiae (Diptera: Culicidae)

NARCIS (Netherlands)

Mukabana, W.R.; Takken, W.; Seda, P.; Killeen, G.F.; Hawley, W.A.; Knols, B.G.J.

2002-01-01

The success of distinguishing blood meal sources of Anopheles gambiae Giles through deoxyribonucleic acid (DNA) profiling was investigated by polymerase chain reaction (PCR) amplification at the TC-11 and VWA human short tandem repeats (STR) loci. Blood meal size and locus had no significant effect

Radio-oxidative membrane damage and its possible role as an indicator of radiation exposure

International Nuclear Information System (INIS)

Amit Kumar; Pandey, B.N.; Mishra, K.P.

2004-01-01

Cellular membranes have been recognized as a sensitive target in the mechanism of ionizing radiation-induced cell killing. In our laboratory, studies have been devoted to investigations on gamma radiation induced oxidative damage to model and cellular membrane damage by employing fluorescence and electron spin resonance (ESR) methods Considerable evidences has accumulated to suggest that radiation induced oxidative damage was related to apoptotic death of a variety of cells in culture. Radiation induced damage involving lipid peroxidation, altered bilayer fluidity, permeability changes and intracellular generated ROS have been evaluated by chemical and physical methods. Modification of damage by structural modulating agents such as cholesterol and antioxidants such as eugenol, ascorbic acid, ellagic acid, triphala have been extensively investigated. Generation of intracellular ROS in radiation stressed normal cell e.g. mouse thymocytes, tumor cells e.g. Ehrlich ascites cells and human cervical cell line were evaluated after exposure from low to moderate doses of α-radiation. Results suggest that modulation of intracellular ROS level may be an important approach to alter radio-cytotoxicity of cells. This presentation would describe results of our study together with an overview of free radical mediated oxidative damage to cellular membrane as an indicator of radiation exposure. (author)

Effects of acid rain and sulfur dioxide on marble dissolution

Science.gov (United States)

Schuster, Paul F.; Reddy, Michael M.; Sherwood, Susan I.

1994-01-01

Acid precipitation and the dry deposition of sulfur dioxide (SO2) accelerate damage to carbonate-stone monuments and building materials. This study identified and quantified environmental damage to a sample of Vermont marble during storms and their preceding dry periods. Results from field experiments indicated the deposition of SO2 gas to the stone surface during dry periods and a twofold increase in marble dissolution during coincident episodes of low rain rate and decreased rainfall pH. The study is widely applicable to the analysis of carbonate-stone damage at locations affected by acid rain and air pollution.

Transport properties of poly(GACT)–poly(CTGA) deoxyribonucleic acid

Indian Academy of Sciences (India)

interface and the role of tube radius of nanotube contacts on the electronic transmission ... approaches, mostly use strictly one-dimensional tight-binding models [18–21] .... where ΣL(ΣR) is the self-energy matrix resulting from the coupling of the DNA .... where mα and mα run over the interfacial end-atoms of the SWNTs. gα.

Reversible entrapment of plasmid deoxyribonucleic acid on different chromatographic supports.

Science.gov (United States)

Gabor, Boštjan; Černigoj, Urh; Barut, Miloš; Štrancar, Aleš

2013-10-11

HPLC based analytical assay is a powerful technique that can be used to efficiently monitor plasmid DNA (pDNA) purity and quantity throughout the entire purification process. Anion exchange monolithic and non-porous particle based stationary phases were used to study the recovery of the different pDNA isoforms from the analytical column. Three differently sized pDNA molecules of 3.0kbp, 5.2kbp and 14.0kbp were used. Plasmid DNA was injected onto columns under the binding conditions and the separation of the isoforms took place by increasing the ionic strength of the elution buffer. While there was no substantial decrease of the recovered supercoiled and linear isoforms of the pDNA with the increase of the plasmid size and with the increase of the flow rate (recoveries in all cases larger than 75%), a pronounced decrease of the oc isoform recovery was observed. The entrapment of the oc pDNA isoform occurred under non-binding conditions as well. The partial oc isoform elution from the column could be achieved by decreasing the flow rate of the elution mobile phase. The results suggested a reversible entrapment of the oc isoform in the restrictions within the pores of the monolithic material as well as within the intra-particle space of the non-porous particles. This phenomenon was observed on both types of the stationary phase morphologies and could only be connected to the size of a void space through which the pDNA needs to migrate. A prediction of reversible pDNA entrapment was successfully estimated with the calculation of Peclet numbers, Pe, which defines the ratio between a convective and diffusive mass transport. Copyright © 2013 Elsevier B.V. All rights reserved.

Host Specificity of Salmonella typhimurium Deoxyribonucleic Acid Restriction and Modification

Science.gov (United States)

Slocum, Harvey; Boyer, Herbert W.

1973-01-01

The restriction and modification genes of Salmonella typhimurium which lie near the thr locus were transferred to a restrictionless mutant of Escherichia coli. These genes were found to be allelic to the E. coli K, B, and A restriction and modification genes. E. coli recombinants with the restriction and modification host specificity of S. typhimurium restricted phage λ that had been modified by each of the seven known host specificities of E. coli at efficiency of plating levels of about 10−2. Phage λ modified with the S. typhimurium host specificity was restricted by six of the seven E. coli host specificities but not by the RII (fi− R-factor controlled) host specificity. It is proposed that the restriction and modification enzymes of this S. typhimurium host specificity have two substrates, one of which is a substrate for the RII host specificity enzymes. PMID:4570605

Purification of influenza deoxyribonucleic acid-based vaccine using agmatine monolith.

Science.gov (United States)

Bicho, D; Caramelo-Nunes, C; Sousa, A; Sousa, F; Queiroz, J A; Tomaz, C T

2016-02-15

Lately, researchers have made several efforts to improve vaccine production to fight highly contagious respiratory diseases like influenza. One of the most promising options for reducing the impact of this virus is DNA vaccination. However, a large quantity of highly pure plasmid DNA (pDNA) is necessary to attain this goal. The present work describes the production and purification of the plasmid NTC7482-41H-VA2HA expressing influenza virus hemagglutinin using an agmatine monolith. This ligand was chosen to purify supercoiled (sc) pDNA from complex lysates because of its versatile multimodal character. Its natural intervention in several biological systems together with its similarity with the highly studied arginine ligand allowed the development of a simpler and more specific purification process. Agmatine works under two strategies: descending ammonium sulfate gradient and ascending sodium chloride gradient. Furthermore, pH manipulation revealed an important role in pDNA isoforms selectivity. Dynamic binding capacity (DBC) experiments were performed varying different parameters and showed an increase with pDNA concentration, while high flow rate and high pH had the opposite effect. Sc pDNA was purified with high yield and was efficient with respect to cell transfection and cell viability. This monolith showed to be appropriate to purify the plasmid NTC7482-41H-VA2HA, providing a valuable tool for pDNA influenza vaccines preparation. Copyright © 2016. Published by Elsevier B.V.

Effect of tubular damage by mercuric chloride on kidney function and some urinary enzymes in the dog

Energy Technology Data Exchange (ETDEWEB)

Ellis, B G; Price, R G; Topham, J C

1973-01-01

Alkaline and acid phosphatases, ..beta..-glucosidase, ..beta..-galactosidase, N-acetyl-..beta..-glucosaminidase and lactate dehydrogenase were monitored in the urine and serum of dogs with renal tubular damage induced by a series of increasing doses of mercuric chloride. Evidence is presented that the assay of urinary alkaline and acid phosphatase is the most sensitive method of detecting renal tubular damage in the dog. The clearance of (/sup 14/C)-propranolol was compared before and after the administration of mercuric chloride. In the presence of tubular damage the blood half-life of propranolol and the rate of excretion of metabolites in the urine were increased. 35 references, 7 tables.

Hypochlorite-induced damage to proteins

DEFF Research Database (Denmark)

Hawkins, C L; Davies, Michael Jonathan

1998-01-01

Stimulated monocytes and neutrophils generate hypochlorite (HOCl) via the release of the enzyme myeloperoxidase and hydrogen peroxide. HOCl damages proteins by reaction with amino acid side-chains or backbone cleavage. Little information is available about the mechanisms and intermediates involved...... in these reactions. EPR spin trapping has been employed to identify radicals on proteins, peptides and amino acids after treatment with HOCl. Reaction with HOCl gives both high- and low-molecular-mass nitrogen-centred, protein-derived radicals; the yield of the latter increases with both higher HOCl:protein ratios...... and enzymic digestion. These radicals, which arise from lysine side-chain amino groups, react with ascorbate, glutathione and Trolox. Reaction of HOCl-treated proteins with excess methionine eliminates radical formation, which is consistent with lysine-derived chloramines (via homolysis of N-Cl bonds) being...

Specific chemical and structural damage to proteins produced by synchrotron radiation.

Science.gov (United States)

Weik, M; Ravelli, R B; Kryger, G; McSweeney, S; Raves, M L; Harel, M; Gros, P; Silman, I; Kroon, J; Sussman, J L

2000-01-18

Radiation damage is an inherent problem in x-ray crystallography. It usually is presumed to be nonspecific and manifested as a gradual decay in the overall quality of data obtained for a given crystal as data collection proceeds. Based on third-generation synchrotron x-ray data, collected at cryogenic temperatures, we show for the enzymes Torpedo californica acetylcholinesterase and hen egg white lysozyme that synchrotron radiation also can cause highly specific damage. Disulfide bridges break, and carboxyl groups of acidic residues lose their definition. Highly exposed carboxyls, and those in the active site of both enzymes, appear particularly susceptible. The catalytic triad residue, His-440, in acetylcholinesterase, also appears to be much more sensitive to radiation damage than other histidine residues. Our findings have direct practical implications for routine x-ray data collection at high-energy synchrotron sources. Furthermore, they provide a direct approach for studying the radiation chemistry of proteins and nucleic acids at a detailed, structural level and also may yield information concerning putative "weak links" in a given biological macromolecule, which may be of structural and functional significance.

Test of physiological parameters for the judgement of spruce damage. Untersuchung physiologischer Kenngroessen zur Beurteilung des Schadenszustandes von Fichten

Energy Technology Data Exchange (ETDEWEB)

Naumann, R.; Ludewig, M.; Fenner, R.; Lalk, I.; Bigdon, M.; Doerffling, K. (Hamburg Univ. (Germany, F.R.). Inst. fuer Allgemeine Botanik und Botanischer Garten)

1988-01-01

The diagnostic value of several physiological parameters for the evaluation of free damage in a ninety years old spruce stand near Ratzeburg (Northern Germany) has been studied. The physiological parameters studied were: level of abscisic acid (ABA) and proline in green, healthy-looking needles of trees with different degrees of damage, the qualitative and quantitative variation of free and bound amino acids, the activity of water soluble peroxidase, the emission of ethylene and the water status. The degree of tree damage was characterized according to the loss of needles. The results show that twigs from trees with strong symptoms of damage had lower values of water potential and turgor potential in comparison to trees with less severe symptoms. During the winter season these differences were less pronounced or even not observable. Green needles from trees with strong needle loss produced more ethylene and had higher levels of abscisic acid and proline than needles from undamaged trees. (orig./KG).

Radiation damage to histones

International Nuclear Information System (INIS)

Mee, L.K.; Adelstein, S.J.

1985-01-01

The damage to histones irradiated in isolation is being elaborated to aid the identification of the crosslinking sites in radiation-induced DNA-histone adducts. Histones are being examined by amino acid analysis to determine the destruction of residues and by polyacrylamide gel electrophoresis to delineate changes in conformation. For the slightly lysine-rich histone, H2A, a specific attack on selective residues has been established, the aromatic residues, tyrosine and phenylalanine, and the heterocyclic residue, histidine, being significantly destroyed. In addition, a significant increase in aspartic acid was found; this may represent a radiation product from scission of the ring in the histidine residues. The similarity of the effects on residues in nitrous oxide-saturated and nitrogen-saturated solutions suggests that OH . and e/sub aq//sup -/ are equally efficient and selective in their attack. On gel electrophoresis degradation of the histone H2A was found to be greatest for irradiations in nitrous oxide-saturated solutions, suggesting CH . is the most effective radical for producing changes in conformation; O/sub 2//sup -/ was essentially ineffective. Other histones are being examined for changes in amino acid composition, conformation, and for the formation of radiation products

Effects of wind and simulated acid mist on leaf cuticles

International Nuclear Information System (INIS)

Hoad, S.P.; Jeffree, C.E.; Grace, J.

1994-01-01

The combined effect of wind and simulated acid mist on leaf cuticles was investigated in beech (Fagus sylvatica L.) and birch (Betula pubescens Ehr.). Macroscopic and microscopic features of wind damage are described. Visibly damaged leaf area and the numbers of microscopic cuticular lesions were measured. The cuticular conductance to water vapour (g c ) of the astomatous adaxial surfaces of the leaves was measured by a gravimetric method. Field experimenntal sites were selected to provide either: 1. Direct wind action on widely-spaced plants caused by high speed and impaction of wind-blown particles, but with minimal mutual leaf abrasion 2. Indirect wind action via a high degree of mutual abrasion between closely-spaced plants. Direct wind action increased water loss via the leaf adaxial cuticle two- to three-fold in each species, by increasing the numbers of microscopic cuticular lesions. Indirect wind action caused more visible damage to leaves than direct wind action, increased g c by about threefold compared with complete shelter, and induced the most cuticular lesions. Acid mists at pH 3 or pH 5 were applied to the plants in situ at weekly intervals over a 100-day period. In sheltered plants, no effect of acid mist was detected on visibly damaged leaf area, the numbers of microscopic cuticular lesions, or on g c . However, acid mists in combination with wind exposure caused significant effects on cuticular integrity that were dependent on the type of wind action. Direct wind action combined with pH 3 acid mist resulted in the largest numbers of microscopic cuticular lesions, and the highest g c . By contrast, indirect wind action combined with pH 3 acid mist caused most visible damage to leaf tissue, but fewer microscopic lesions, and lower g c , than in plants treated with water mist. In severely-abraded leaves exposed to indirect wind action and low-pH acid rain, g c may be reduced by wound-isolation of blocks of non-functional leaf tissue. (orig.)

21 CFR 864.7280 - Factor V Leiden DNA mutation detection systems.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Factor V Leiden DNA mutation detection systems....7280 Factor V Leiden DNA mutation detection systems. (a) Identification. Factor V Leiden deoxyribonucleic acid (DNA) mutation detection systems are devices that consist of different reagents and...

21 CFR 862.3360 - Drug metabolizing enzyme genotyping system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Drug metabolizing enzyme genotyping system. 862... Test Systems § 862.3360 Drug metabolizing enzyme genotyping system. (a) Identification. A drug metabolizing enzyme genotyping system is a device intended for use in testing deoxyribonucleic acid (DNA...

Identification of Meconopsis species by a DNA barcode sequence ...

African Journals Online (AJOL)

Deoxyribonucleic acid (DNA) barcoding is a novel technology that uses a standard DNA sequence to facilitate species identification. Species identification is necessary for the authentication of traditional plant based medicines. Although a consensus has not been agreed regarding which DNA sequences can be used as ...

Different patterns of gene expression in rice varieties undergoing a ...

African Journals Online (AJOL)

Some genes specifically up-regulated in infected 9804-Rxo1 were defenserelated, including the genes encoding pathogenesis-related protein, terpene synthase family, transcription factors (TFs) AP2 domain containing protein, myb-like deoxyribonucleic acid (DNA)- binding domain containing protein, and C2H2-type ...

Report of foliar necrosis of potato caused by Cochliobolus lunatus in ...

African Journals Online (AJOL)

During the winter season of 2011, Cochliobolus lunatus was isolated from necrotized leaves of potato in potato plantations of Burdwan District, West Bengal State, India. The isolate was identified using standard monographs and taxonomic keys and confirmed molecularly using the Ribosomal Deoxyribonucleic acid (rDNA) ...

Golden rain tree leaf extracts as potential inhibitor of lipid ...

African Journals Online (AJOL)

This study was designed to evaluate the peroxyl radical scavenging capacity and deoxyribonucleic acid (DNA) protective effect of extract/fractions of Koelreuteria paniculata Laxm. (Golden rain tree) in lipid peroxidation assay and calf thymus DNA protection assay. The leaves of the plant were extracted with different ...

Is DNA Alive? a Study of Conceptual Change through Targeted Instruction

Science.gov (United States)

Witzig, Stephen B.; Freyermuth, Sharyn K.; Siegel, Marcelle A.; Izci, Kemal; Pires, J. Chris

2013-01-01

We are involved in a project to incorporate innovative assessments within a reform-based large-lecture biochemistry course for nonmajors. We not only assessed misconceptions but purposefully changed instruction throughout the semester to confront student ideas. Our research questions targeted student conceptions of deoxyribonucleic acid (DNA)…

Metabolite Damage and Metabolite Damage Control in Plants

Energy Technology Data Exchange (ETDEWEB)

Hanson, Andrew D. [Horticultural Sciences Department and; Henry, Christopher S. [Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, Illinois 60439, email:; Computation Institute, University of Chicago, Chicago, Illinois 60637; Fiehn, Oliver [Genome Center, University of California, Davis, California 95616, email:; de Crécy-Lagard, Valérie [Microbiology and Cell Science Department, University of Florida, Gainesville, Florida 32611, email: ,

2016-04-29

It is increasingly clear that (a) many metabolites undergo spontaneous or enzyme-catalyzed side reactions in vivo, (b) the damaged metabolites formed by these reactions can be harmful, and (c) organisms have biochemical systems that limit the buildup of damaged metabolites. These damage-control systems either return a damaged molecule to its pristine state (metabolite repair) or convert harmful molecules to harmless ones (damage preemption). Because all organisms share a core set of metabolites that suffer the same chemical and enzymatic damage reactions, certain damage-control systems are widely conserved across the kingdoms of life. Relatively few damage reactions and damage-control systems are well known. Uncovering new damage reactions and identifying the corresponding damaged metabolites, damage-control genes, and enzymes demands a coordinated mix of chemistry, metabolomics, cheminformatics, biochemistry, and comparative genomics. This review illustrates the above points using examples from plants, which are at least as prone to metabolite damage as other organisms.

Evaluation of the risk of liver damage from the use of 5-aminolevulinic acid for intra-operative identification and resection in patients with malignant gliomas

DEFF Research Database (Denmark)

Offersen, Cecilie Mørck; Skjoeth-Rasmussen, Jane

2017-01-01

BACKGROUND: The clinical efficacy of 5-aminolevulinic acid (5-ALA) for fluorescence-guided surgery of malignant gliomas is evident from several studies; however, as post-operative elevations of liver enzymes have been seen, there is a potential risk of liver damage upon administration. The aim...... (September 2012-September 2014) at the University Hospital of Copenhagen, Rigshospitalet, was conducted. All patients received a pre-operative dose of 20 mg/kg bodyweight 5-ALA. The pre- and post-operative enzyme levels of alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase...

Involvement of membrane lipids in radiation damage to potassium-ion permeability of Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Suzuki, S [Tokyo Univ. (Japan). Inst. for Medical Science; Akamatsu, Y

1978-02-01

Radiation damage to K/sup +/ permeability of an unsaturated fatty acid auxotroph of E.coli grown with oleate or linolenate was investigated at different temperatures. A remarkable effect of radiation was observed at 0/sup 0/C with cells that had been grown in linolenate at 42/sup 0/C. This indicates that, besides protein, membrane lipids at least are involved in the radiation damage. The damage also seems to be affected by the fluidity of membrane lipids.

Smoke damages of forest from the biologic standpoint

Energy Technology Data Exchange (ETDEWEB)

Kisser, J

1966-01-01

Biological aspects of smoke damages are reviewed with special regard to forests. Due to the long exposures, smoke is more harmful to forests than to farm plants. Invisible physiological damages due to protoplasm lesions are counteracted by the regenerative effect of certain enzyme systems. Insoluble solid emissions reduce both light and assimilation, while soluble particles may penetrate into the plant or the soil, causing changes in the vegetation. Damage caused by soot and photochemical smog are detailed. Sulfur dioxide and hydrofluoric acid are two basic gaseous pollutants damaging forests. The importance of the damage is primarily determined by concentration and duration of exposure, with emphasis on concentration. In high concentrations, the substances are dissolved in the mesophyll cell wall fluid, causing point-like necroses. Low concentrations lead to necroses on the ends and edges of leaves and needles. The damages are also influenced by climatic factors. The transpiration and consequently the sensitivity for SO/sub 2/ are dependent of the relative humidity. Sharp increase in sensitivity can be observed from 60% to 90% relative humidity. There is no direct connection between transpiration rate and assimilation performance. High transpiration coefficients are characteristic of dry climates. There is no relation between transpiration and sensitivity, while any factor affecting the cuticular openings influences the extent of the damage. The resistance to smoke cannot be improved in forests by means of fertilizers. Different resistances of various species as well as problems of breeding smoke-resistant species are discussed.

Antioxidant effects of betaine against Indomethacin-induced gastric damage in rats

Directory of Open Access Journals (Sweden)

M Alirezaei

2016-10-01

Full Text Available Introduction: Betaine (trimethyl glycine is known as methyl group donor and antioxidant in previous reports. The aim of this study was to assess the antioxidant effects of betaine in Indomethacin-induced gastric damages. Methods: Thirty-two adult male Sprague–Dawley rats in an experimental study were divided into four equal groups as follow: Control, Indomethacin, Betaine-indomethacin and Ascorbic acid-indomethacin. Control and indomethacin groups received normal saline and betaine and ascorbic acid-pretreated rats were administrated betaine (1.5% of the total diet and ascorbic acid (50 mg/kg body weight for 15 consecutive days, respectively. After 24 h fasting, all of the groups received indomethacin (48 mg/kg body weight and control group received distilled water. Results: Indomethacin administration increased gastric ulcer occurrence (% in comparison with control group and betaine pretreatment significantly decreased ulcer occurrence (% when compared to the other groups (P=0.0017. Gastric wall glutathione peroxidase (GPx activity was significantly lower in indomethacin group in comparison with the other groups (P=0.0012 while, betaine and ascorbic acid pretreatment increased GPx activity in comparison with indomethacin group (P=0.0012. Catalase activity was significantly higher in betaine-pretreated rats in comparison with indomethacin and ascorbic acid-indomethacin groups (P=0.0015. Lipid peroxidation significantly decreased in betaine and ascorbic acid pretreated groups (P=0.0013. Conclusion: These results showed beneficial antioxidant effects of betaine against gastric damages induced by indomethacin in rats.

Interleukin-6 deficiency reduces the brain inflammatory response and increases oxidative stress and neurodegeneration after kainic acid-induced seizures

DEFF Research Database (Denmark)

Penkowa, M; Molinero, A; Carrasco, J

2001-01-01

and were killed six days later. Morphological damage to the hippocampal field CA1-CA3 was seen after kainic acid treatment. Reactive astrogliosis and microgliosis were prominent in kainic acid-injected normal mice hippocampus, and clear signs of increased oxidative stress were evident. Thus......The role of interleukin-6 in hippocampal tissue damage after injection with kainic acid, a rigid glutamate analogue inducing epileptic seizures, has been studied by means of interleukin-6 null mice. At 35mg/kg, kainic acid induced convulsions in both control (75%) and interleukin-6 null (100%) mice......, and caused a significant mortality (62%) only in the latter mice, indicating that interleukin-6 deficiency increased the susceptibility to kainic acid-induced brain damage. To compare the histopathological damage caused to the brain, control and interleukin-6 null mice were administered 8.75mg/kg kainic acid...

Radiation damages in chemical components of organic scintillator detectors

International Nuclear Information System (INIS)

Fernandes Neto, Jose Maria

2003-01-01

Samples containing PPO (1%, g/ml), diluted in toluene, they were irradiated in a 60 Co irradiator (6.46 kGy/h) at different doses. The PPO concentration decay bi-exponentially with the dose, generating the degradation products: benzoic acid, benzamide and benzilic alcohol. The liquid scintillator system was not sensitive to the radiation damage until 20 kGy. Otherwise, the pulse height analysis showed that dose among 30 to 40 kGy generate significant loss of quality of the sensor (liquid scintillating) and the light yield was reduced in half with the dose of (34.04 ± 0.80) kGy. This value practically was confirmed by the photo peak position analysis that resulted D 1/2 = (31.7 ± 1,4) kGy, The transmittance, at 360 nm, of the irradiated solution decreased exponentially. The compartmental model using five compartments (fast decay PPO, slow decay PPO, benzamide, benzoic acid and benzilic alcohol) it was satisfactory to explain the decay of the PPO in its degradation products in function of the dose. The explanation coefficient r 2 = 0.985636 assures that the model was capable to explain 98.6% of the experimental variations. The Target Theory together with the Compartmental Analysis showed that PPO irradiated in toluene solution presents two sensitive molecular diameters both of them larger than the true PPO diameter. >From this analysis it showed that the radiolytic are generated, comparatively, at four toluene molecules diameter far from PPO molecules. For each one PPO-target it was calculated the G parameter (damage/100 eV). For the target expressed by the fast decay the G value was (418.4 ± 54.1) damages/100 eV, and for the slow decay target the G value was (54.5 ± 8.9) damages/100 eV. The energies involved in the chemical reactions were w (0.239 ± 0.031) eV/damage (fast decay) and w = (1 834 ± 0.301) eV/damage (slow decay). (author)

DNA damage in human lymphocytes exposed to four food additives in vitro.

Science.gov (United States)

Yilmaz, Serkan; Unal, Fatma; Yüzbaşıoğlu, Deniz; Celik, Mustafa

2014-11-01

In vitro genotoxic effects of antioxidant additives, such as citric acid (CA) and phosphoric acid (PA) and their combination, as well as antimicrobial additives, such as benzoic acid (BA) and calcium propionate (CP), on human lymphocytes were determined using alkaline single-cell gel electrophoresis. There was a significant increase in the DNA damage in human lymphocytes after 1 h of in vitro exposure to CA, PA, BA and CP (200, 25-200, 50-500, 50-1000 μg/mL, respectively). The combination of CA and PA significantly increased the mean tail intensity at all the concentrations used (25-200 μg/mL) and significantly increased the mean tail length mainly after higher concentrations (100 and 200 μg/mL). Data in this study showed that the concentrations of food additives used induce DNA damage and PA was the most genotoxic and CA was less genotoxic additives among them. © The Author(s) 2012.

Assays for urinary biomarkers of oxidatively damaged nucleic acids

DEFF Research Database (Denmark)

Weimann, Allan; Broedbaek, Kasper; Henriksen, Trine

2012-01-01

Abstract The analysis of oxidized nucleic acid metabolites can be performed by a variety of methodologies: liquid chromatography coupled with electrochemical or mass-spectrometry detection, gas chromatography coupled with mass spectrometry, capillary electrophoresis and ELISA (Enzyme-linked immun...

Management of mining-related damages in abandoned underground coal mine areas using GIS

International Nuclear Information System (INIS)

Lee, U.J.; Kim, J.A.; Kim, S.S.; Kim, W.K.; Yoon, S.H.; Choi, J.K.

2005-01-01

The mining-related damages such as ground subsidence, acid mine drainage (AMD), and deforestation in the abandoned underground coal mine areas become an object of public concern. Therefore, the system to manage the mining-related damages is needed for the effective drive of rehabilitation activities. The management system for Abandoned Underground Coal Mine using GIS includes the database about mining record and information associated with the mining-related damages and application programs to support mine damage prevention business. Also, this system would support decision-making policy for rehabilitation and provide basic geological data for regional construction works in abandoned underground coal mine areas. (authors)

DNA damage by reactive species: Mechanisms, mutation and repair

Indian Academy of Sciences (India)

2012-06-25

Jun 25, 2012 ... crosslinks can also affect the structure of DNA significantly. ... H2O2 by converting it into water, reaction of H2O2 with ..... Damaged nucleotide flipping by (a) AGT due to intercalation of an amino acid (Arg128) (pdb 1t38) and ...

A paradigm study for assessment of phenylalanine's damage under arc-discharge irradiation

Energy Technology Data Exchange (ETDEWEB)

Ke Zhigang [Laboratory of Ion Beam Bio-engineering, Institute of Plasma Physics of Chinese Academy of Sciences, P.O. Box 1126, Shushanhu Road 350, Hefei 230031 (China); Huang Qing, E-mail: huangq@ipp.ac.c [Laboratory of Ion Beam Bio-engineering, Institute of Plasma Physics of Chinese Academy of Sciences, P.O. Box 1126, Shushanhu Road 350, Hefei 230031 (China); Su Xi; Jiang Jiang; Wang Xiangqin; Yu Zengliang [Laboratory of Ion Beam Bio-engineering, Institute of Plasma Physics of Chinese Academy of Sciences, P.O. Box 1126, Shushanhu Road 350, Hefei 230031 (China)

2010-05-15

Energetic ions induce important biological effects and the research into radiolysis of amino acids can help to clarify radiolysis of proteins. For this purpose, arc-discharge induced radiolysis of the benzyl-containing aromatic amino acid phenylalanine in aqueous solution was studied and the damage was assessed quantitatively. The energetic ions were produced by arc-discharge in nitrogen and argon atmosphere. The arc-discharge induced chemical reactions of the biomolecule in aqueous solution were detected and analyzed by means of UV-Vis absorption, fluorescence, Fourier transformation infrared (FTIR) spectroscopy and high performance liquid chromatography (HPLC). Based on the multiple spectroscopic approach, the damage can be evaluated in a more reliable and convenient way. The fluorescence analysis in this case appears to be a more direct indicator for the assessment of damage, where it reveals that the damage increases with the irradiation time exponentially. On the contrary, the 'plateau region' or 'saddle-shape' apparently shown both in our rough absorption analysis and ninhydrin reaction test, similar to the previously reported feature of the dose effect for low-energy-ion induced damage, may be just a consequence with varied reactions and processes involved at different stages. This work thus demonstrated that application of appropriate combination of spectroscopic tools can effectively dissect the diversity of the radiolysis reaction system and assess the biomolecular damage properly.

Dual Effects of Alpha-Hydroxy Acids on the Skin

Directory of Open Access Journals (Sweden)

Sheau-Chung Tang

2018-04-01

Full Text Available AHAs are organic acids with one hydroxyl group attached to the alpha position of the acid. AHAs including glycolic acid, lactic acid, malic acid, tartaric acid, and citric acid are often used extensively in cosmetic formulations. AHAs have been used as superficial peeling agents as well as to ameliorate the appearance of keratoses and acne in dermatology. However, caution should be exercised in relation to certain adverse reactions among patients using products with AHAs, including swelling, burning, and pruritus. Whether AHAs enhance or decrease photo damage of the skin remains unclear, compelling us to ask the question, is AHA a friend or a foe of the skin? The aim of this manuscript is to review the various biological effects and mechanisms of AHAs on human keratinocytes and in an animal model. We conclude that whether AHA is a friend or foe of human skin depends on its concentration. These mechanisms of AHAs are currently well understood, aiding the development of novel approaches for the prevention of UV-induced skin damage.

Recovery of oxidative stress-induced damage in Cisd2-deficient cardiomyocytes by sustained release of ferulic acid from injectable hydrogel.

Science.gov (United States)

Cheng, Yung-Hsin; Lin, Feng-Huei; Wang, Chien-Ying; Hsiao, Chen-Yuan; Chen, Hung-Ching; Kuo, Hsin-Yu; Tsai, Ting-Fen; Chiou, Shih-Hwa

2016-10-01

Aging-related oxidative stress is considered a major risk factor of cardiovascular diseases (CVD) and could be associated with mitochondrial dysfunction and reactive oxygen species (ROS) overproduction. Cisd2 is an outer mitochondrial membrane protein and plays an important role in controlling the lifespan of mammals. Ferulic acid (FA), a natural antioxidant, is able to improve cardiovascular functions and inhibit the pathogenetic CVD process. However, directly administering therapeutics with antioxidant molecules is challenging because of stability and bioavailability issues. In the present study, thermosensitive chitosan-gelatin-based hydrogel containing FA was used to treat Cisd2-deficient (Cisd2(-/-)) cardiomyocytes (CM) derived from induced pluripotent stem cells of Cisd2(-/-) murine under oxidative stress. The results revealed that the developed hydrogel could provide a sustained release of FA and increase the cell viability. Post-treatment of FA-loaded hydrogel effectively decreased the oxidative stress-induced damage in Cisd2(-/-) CM via increasing catalase activity and decreasing endogenous reactive oxygen species (ROS) production. The in vivo biocompatibility of FA-loaded hydrogel was confirmed in subcutaneously injected rabbits and intramyocardially injected Cisd2(-/-) mice. These results suggest that the thermosensitive FA-loaded hydrogel could rescue Cisd2(-/-) CM from oxidative stress-induced damage and may have potential applications in the future treatment of CVD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Formation and repair of gamma-ray induced nucleic acid base damage in bacteria and mammalian cells. Final report, September 1, 1973--August 31, 1976

International Nuclear Information System (INIS)

Cerutti, P.A.

1976-01-01

Results are summarized from a three-year study of the formation and repair of γ-ray induced thymine damage in bacteria and mammalian cells. A systematic study was made of the formation of a specific type of ionizing radiation induced base damage under in vivo conditions. Assay for the determination of γ-ray products of the 5,6-dihydroxy-dihydrothymine type (alkaline-acid degradation assay) and a method for the determination of the formation of 5-methylene-uracil radicals (formation of ( 3 H)H 2 O from thymine-methyl ( 3 H)) are discussed. The radiation-chemical reactivity of thymine decreased according to the following pattern in different biological systems: phi X174-DNA greater than E. coli DNA = phi X174 phage much greater than HeLa chromatin greater than E. coli cells greater than human fibroblasts WI-38. In WI-38 the efficiency of formation of 5-methylene-uracil radicals was 1.6 x 10 -3 per Krad and 10 6 daltons DNA and of products of the 5,6-dihydroxy-dihydrothymine type 0.54 x 10 -3 per Krad per 10 6 daltons DNA (uncorrected). It was concluded that γ-rays produce DNA single strand breaks and (total) base damage with comparable efficiencies under in vivo conditions in cultured cells. A list is included of 18 published papers that report the findings in detail

Making Worms Glow

Indian Academy of Sciences (India)

Permanent link: http://www.ias.ac.in/article/fulltext/reso/023/03/0291-0298. Keywords. Nanotechnology, nanomachines, I-switch, FRET, fluorophore, endocytosis, pH sensor, C.elegans. Abstract. Deoxyribonucleic acid (DNA) is the molecule that carries geneticinformation in a cell. The field of DNA nanotechnologyaims to use ...

DNA-based population density estimation of black bear at northern ...

African Journals Online (AJOL)

The analysis of deoxyribonucleic acid (DNA) microsatellites from hair samples obtained by the non-invasive method of traps was used to estimate the population density of black bears (Ursus americanus eremicus) in a mountain located at the county of Lampazos, Nuevo Leon, Mexico. The genotyping of bears was ...

Toxicological aspects of interesterified fat: Brain damages in rats.

Science.gov (United States)

D'avila, Lívia Ferraz; Dias, Verônica Tironi; Vey, Luciana Taschetto; Milanesi, Laura Hautrive; Roversi, Karine; Emanuelli, Tatiana; Bürger, Marilise Escobar; Trevizol, Fabíola; Maurer, H Luana

2017-07-05

In recent years, interesterified fat (IF) has been used to replace hydrogenated vegetable fat (HVF), rich in trans isomers, being found in processed foods. Studies involving IF have shown deleterious influences on the metabolic system, similarly to HVF, whereas no studies regarding its influence on the central nervous system (CNS) were performed. Rats from first generation born and maintained under supplementation (3g/Kg, p.o.) of soybean-oil or IF until adulthood were assessed on memory, biochemical and molecular markers in the hippocampus. IF group showed higher saturated fatty acids and linoleic acid and lower docosahexaenoic acid incorporation in the hippocampus. In addition, IF supplementation impaired short and long-term memory, which were related to increased reactive species generation and protein carbonyl levels, decreased catalase activity, BDNF and TrkB levels in the hippocampus. To the best of our knowledge, this is the first study to show that lifelong IF consumption may be related to brain oxidative damage, memory impairments and neurotrophins modifications, which collectively may be present indifferent neurological disorders. In fact, the use of IF in foods was intended to avoid damage from HVF consumption; however this substitute should be urgently reviewed, since this fat can be as harmful as trans fat. Copyright © 2017 Elsevier B.V. All rights reserved.

Synergistic Application of Black Tea Extracts and Lactic Acid Bacteria in Protecting Human Colonocytes against Oxidative Damage.

Science.gov (United States)

Zhao, Danyue; Shah, Nagendra P

2016-03-23

In view of the potential of lactic acid bacteria (LAB) to enhance the antioxidant activity of food products, this work explored the effectiveness of LAB fermented black tea samples in alleviating H2O2-induced oxidative stress in human colonocytes. The antioxidant capacity of tea samples was evaluated in terms of cyto-protectiveness, mitochondria membrane potential (Δψm)-stabilizing activity, ROS-inhibitory effect, and antioxidant enzyme-modulating activity. The effect on oxidative DNA damage and repair was studied in CCD 841 by comet assay. Results showed that the protective effect of tea pretreatment was more pronounced in normal cells (CCD 841) than in carcinomas (Caco-2), and fermented samples were invariably more effective. Higher cell viability and Δψm were maintained and ROS production was markedly inhibited with tea pretreatment. The fermented tea samples also remarkably stimulated DNA repair, resulting in fewer strand breaks and oxidative lesions. Our study implied that LAB fermentation may be an efficient way to enhance the antioxidative effectiveness of black tea flavonoid-enriched foods.

Thioacetamide-induced changes in the body weight, kidney weight and the total nucleic acids content of kidney of mouse

International Nuclear Information System (INIS)

Shakoori, Abdul Rauf; Ashraf, Fauzia.

1976-01-01

Effects of thioacetamide (TAA) on the body weight, kidney weight and the total nucleic acids content of kidney of mouse were studied. TAA 1% and 2% solutions were injected intraperitoneally, twice with an interval of 24 hours in two different batches of male mice. In this way one batch received a total dose of 100 mg TAA/Kg body wt. while the other got a total dose of 200 mg TAA/Kg. Both the body as well as kidney weights decrease after TAA treatment. A total dose of 200 mg/Kg is a stronger inhibitor of growth as compared with that of 100 mg/Kg. The nucleic acids content show an increase after the drug treatment. The ribonucleic acid content of kidney increased from an average value of 4.30+0.14 mg/g kidney to 4.60+-0.22 mg/g kidney after 1% TAA treatment. The increase in 2% TAA treated mice is slightly more prominent. The deoxyribonucleic acid (DNA) content of kidney are likewise affected. After an initial increase in 1% TAA-treated animals, the DNA content gradually fall down to normal control values. Administration of 2% TAA solution causes an average increase of 21% i.e. from 1.93+-0.19 mg/g kidney wt to 2.26+-0.23 mg/g kidney wt. The size of cell, nucleus and nucleolus also increased after drug treatment, which mainly occurred during the first 24 hours of the post-treatment period

Bibliography for acid-rock drainage and selected acid-mine drainage issues related to acid-rock drainage from transportation activities

Science.gov (United States)

Bradley, Michael W.; Worland, Scott C.

2015-01-01

Acid-rock drainage occurs through the interaction of rainfall on pyrite-bearing formations. When pyrite (FeS2) is exposed to oxygen and water in mine workings or roadcuts, the mineral decomposes and sulfur may react to form sulfuric acid, which often results in environmental problems and potential damage to the transportation infrastructure. The accelerated oxidation of pyrite and other sulfidic minerals generates low pH water with potentially high concentrations of trace metals. Much attention has been given to contamination arising from acid mine drainage, but studies related to acid-rock drainage from road construction are relatively limited. The U.S. Geological Survey, in cooperation with the Tennessee Department of Transportation, is conducting an investigation to evaluate the occurrence and processes controlling acid-rock drainage and contaminant transport from roadcuts in Tennessee. The basic components of acid-rock drainage resulting from transportation activities are described and a bibliography, organized by relevant categories (remediation, geochemical, microbial, biological impact, and secondary mineralization) is presented.

Moessbauer study of corrosion induced by acid rain

International Nuclear Information System (INIS)

Arshed, M.; Hussain, N.; Siddiqui, M.; Anwar-ul-Islam, M.; Rehman, S.; Butt, N.M.

1997-01-01

Strictly speaking acid rain refers to wet precipitation of pollutants S0/sub 2/SO/sub 3/ and NO/sub x/HNO/sub 3/ which have dissolved in cloud and rain droplets to from sulphuric and nitric acids. Acid rain has seriously damaged pine and spruce forests in Canada, USA and Europe. In these areas it has caused damage to buildings, reduced fish population due to acidification of lakes and rivers, and affected health of human beings as a result of poor water quality. The corrosion products formed in a simulated acid rain environment have been identified with transmission Moessbauer spectroscopy using a /sup 57/Co source. They were found to be gamma-FeOOH, alpha-FeOOH, gamma-Fe/sub 2/O/sub 3/ and a phase with unfamiliar parameters which seems to be amorphous in nature and can be considered as an intermediate phase. (author)

Intrauterine infection/inflammation during pregnancy and offspring brain damages: Possible mechanisms involved

Directory of Open Access Journals (Sweden)

Golan Hava

2004-04-01

Full Text Available Abstract Intrauterine infection is considered as one of the major maternal insults during pregnancy. Intrauterine infection during pregnancy could lead to brain damage of the developmental fetus and offspring. Effects on the fetal, newborn, and adult central nervous system (CNS may include signs of neurological problems, developmental abnormalities and delays, and intellectual deficits. However, the mechanisms or pathophysiology that leads to permanent brain damage during development are complex and not fully understood. This damage may affect morphogenic and behavioral phenotypes of the developed offspring, and that mice brain damage could be mediated through a final common pathway, which includes over-stimulation of excitatory amino acid receptor, over-production of vascularization/angiogenesis, pro-inflammatory cytokines, neurotrophic factors and apoptotic-inducing factors.

Changes in nuclear protein acetylation in u. v. -damaged human cells

Energy Technology Data Exchange (ETDEWEB)

Ramanathan, B.; Smerdon, M.J.

1986-07-01

We have investigated the levels of nuclear protein acetylation in u.v.-irradiated human fibroblasts. We measured the levels of acetylation in total acid-soluble nuclear proteins and observed two distinct differences between the irradiated and unirradiated (control) cells. Immediately after irradiation, there is a wave of protein hyperacetylation (i.e. a total acetylation level greater than that of unirradiated cells) that lasts for 2-6 h depending on the experimental conditions. This hyperacetylation phase is then followed by a hypoacetylation phase, lasting for many hours, and the total level of acetylation does not return to that of control cells until 24-72 h after u.v. damage. Both the magnitude and duration of each phase is dependent on the dose of u.v. light used. The wave of hyperacetylation is more pronounced at low u.v. doses (i.e. less than 5 J/m2), while the wave of hypoacetylation is more pronounced at higher u.v. doses (greater than or equal to 8 J/m2). Furthermore, the duration of each phase is prolonged when cells are exposed to 2 mM hydroxyurea. Examination of the acetylation levels of the individual nuclear proteins indicated that acetylation of the core histones follows the same pattern observed for the total acid-soluble protein fractions. Furthermore, these were the only major proteins in the total acid-soluble fraction observed to undergo the early, rapid hyperacetylation immediately following u.v. damage. Acetylation of histone H1 was negligible in both damaged and control cells, while three prominent non-histone proteins were acetylated only after long labeling times (greater than 4 h) in each case, gradually becoming hyperacetylated in the u.v.-damaged cells. These results raise the possibility that a causal relationship exists between nuclear protein acetylation and nucleotide excision repair of DNA in human cells.

The nucleosome: orchestrating DNA damage signaling and repair within chromatin.

Science.gov (United States)

Agarwal, Poonam; Miller, Kyle M

2016-10-01

DNA damage occurs within the chromatin environment, which ultimately participates in regulating DNA damage response (DDR) pathways and repair of the lesion. DNA damage activates a cascade of signaling events that extensively modulates chromatin structure and organization to coordinate DDR factor recruitment to the break and repair, whilst also promoting the maintenance of normal chromatin functions within the damaged region. For example, DDR pathways must avoid conflicts between other DNA-based processes that function within the context of chromatin, including transcription and replication. The molecular mechanisms governing the recognition, target specificity, and recruitment of DDR factors and enzymes to the fundamental repeating unit of chromatin, i.e., the nucleosome, are poorly understood. Here we present our current view of how chromatin recognition by DDR factors is achieved at the level of the nucleosome. Emerging evidence suggests that the nucleosome surface, including the nucleosome acidic patch, promotes the binding and activity of several DNA damage factors on chromatin. Thus, in addition to interactions with damaged DNA and histone modifications, nucleosome recognition by DDR factors plays a key role in orchestrating the requisite chromatin response to maintain both genome and epigenome integrity.

Changes in nuclear protein acetylation in u.v.-damaged human cells

International Nuclear Information System (INIS)

Ramanathan, B.; Smerdon, M.J.

1986-01-01

The levels of nuclear protein acetylation in u.v.-irradiated human fibroblasts have been investigated. Initially, we measured the levels of acetylation in total acid-soluble nuclear proteins and observed two distinct differences between the irradiated and unirradiated (control) cells. Immediately after irradiation, there is a 'wave' of protein hyperacetylation that lasts for 2-6 h, followed by a hypoacetylation phase, lasting for many hours, and the total level of acetylation does not return to that of control cells until 24-72 h after u.v. damage. Both the magnitude and duration of each phase is dependent on the dose of u.v. light used. The wave of hyperacetylation is more pronounced at low u.v. doses, while the wave of hypoacetylation is more pronounced at higher u.v. doses. Furthermore, the duration of each phase is prolonged when cells are exposed to 2 mM hydroxyurea, an agent which retards the rate of excision repair at u.v.-damaged sites. Examinations of the acetylation levels of the individual nuclear proteins indicated that acetylation of the core histones follows the same pattern observed for the total acid-soluble protein fractions. Furthermore, these were the only major proteins in the total acid-soluble fraction observed to undergo the early, rapid hyperacetylation immediately following u.v. damage. These results raise the possibility that a causal relationship exists between nuclear protein acetylation and nucleotide excision repair of DNA in human cells. (author)

Environmental exposure to human carcinogens in teenagers and the association with DNA damage

International Nuclear Information System (INIS)

Franken, Carmen; Koppen, Gudrun; Lambrechts, Nathalie; Govarts, Eva; Bruckers, Liesbeth; Den Hond, Elly; Loots, Ilse; Nelen, Vera; Sioen, Isabelle; Nawrot, Tim S.; Baeyens, Willy; Van Larebeke, Nicolas; Boonen, Francis; Ooms, Daniëlla; Wevers, Mai; Jacobs, Griet; Covaci, Adrian; Schettgen, Thomas; Schoeters, Greet

2017-01-01

Background: We investigated whether human environmental exposure to chemicals that are labeled as (potential) carcinogens leads to increased (oxidative) damage to DNA in adolescents. Material and methods: Six hundred 14–15-year-old youngsters were recruited all over Flanders (Belgium) and in two areas with important industrial activities. DNA damage was assessed by alkaline and formamidopyrimidine DNA glycosylase (Fpg) modified comet assays in peripheral blood cells and analysis of urinary 8-hydroxydeoxyguanosine (8-OHdG) levels. Personal exposure to potentially carcinogenic compounds was measured in urine, namely: chromium, cadmium, nickel, 1-hydroxypyrene as a proxy for exposure to other carcinogenic polycyclic aromatic hydrocarbons (PAHs), t,t-muconic acid as a metabolite of benzene, 2,5-dichlorophenol (2,5-DCP), organophosphate pesticide metabolites, and di(2-ethylhexyl) phthalate (DEHP) metabolites. In blood, arsenic, polychlorinated biphenyl (PCB) congeners 118 and 156, hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (DDT) and perfluorooctanoic acid (PFOA) were analyzed. Levels of methylmercury (MeHg) were measured in hair. Multiple linear regression models were used to establish exposure-response relationships. Results: Biomarkers of exposure to PAHs and urinary chromium were associated with higher levels of both 8-OHdG in urine and DNA damage detected by the alkaline comet assay. Concentrations of 8-OHdG in urine increased in relation with increasing concentrations of urinary t,t-muconic acid, cadmium, nickel, 2,5-DCP, and DEHP metabolites. Increased concentrations of PFOA in blood were associated with higher levels of DNA damage measured by the alkaline comet assay, whereas DDT was associated in the same direction with the Fpg-modified comet assay. Inverse associations were observed between blood arsenic, hair MeHg, PCB 156 and HCB, and urinary 8-OHdG. The latter exposure biomarkers were also associated with higher fish intake. Urinary nickel

Environmental exposure to human carcinogens in teenagers and the association with DNA damage

Energy Technology Data Exchange (ETDEWEB)

Franken, Carmen, E-mail: carmen.franken@vito.be [Flemish Institute for Technological Research (VITO), Mol (Belgium); Department of Biomedical Sciences, University of Antwerp, Antwerp (Belgium); Koppen, Gudrun; Lambrechts, Nathalie; Govarts, Eva [Flemish Institute for Technological Research (VITO), Mol (Belgium); Bruckers, Liesbeth [Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Hasselt (Belgium); Den Hond, Elly [Flemish Institute for Technological Research (VITO), Mol (Belgium); Loots, Ilse [Political and Social Sciences, University of Antwerp, Antwerp (Belgium); Nelen, Vera [Provincial Institute for Hygiene, Antwerp (Belgium); Sioen, Isabelle [Department of Public Health, Ghent University, Ghent (Belgium); Department of Food Safety and Food Quality, Ghent University, Ghent (Belgium); Nawrot, Tim S. [Centre for Environmental Sciences, Hasselt University, Diepenbeek (Belgium); Department of Public Health & Primary Care, Leuven University, Leuven (Belgium); Baeyens, Willy [Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel, Brussels (Belgium); Van Larebeke, Nicolas [Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel, Brussels (Belgium); Department of Radiotherapy and Experimental Cancerology, Ghent University, Ghent (Belgium); Boonen, Francis; Ooms, Daniëlla; Wevers, Mai; Jacobs, Griet [Flemish Institute for Technological Research (VITO), Mol (Belgium); Covaci, Adrian [Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp (Belgium); Schettgen, Thomas [Department of Occupational and Social Medicine, RWTH Aachen University, Aachen (Germany); Schoeters, Greet [Flemish Institute for Technological Research (VITO), Mol (Belgium); Department of Biomedical Sciences, University of Antwerp, Antwerp (Belgium); University of Southern Denmark, Institute of Public Health, Department of Environmental Medicine, Odense (Denmark)

2017-01-15

Background: We investigated whether human environmental exposure to chemicals that are labeled as (potential) carcinogens leads to increased (oxidative) damage to DNA in adolescents. Material and methods: Six hundred 14–15-year-old youngsters were recruited all over Flanders (Belgium) and in two areas with important industrial activities. DNA damage was assessed by alkaline and formamidopyrimidine DNA glycosylase (Fpg) modified comet assays in peripheral blood cells and analysis of urinary 8-hydroxydeoxyguanosine (8-OHdG) levels. Personal exposure to potentially carcinogenic compounds was measured in urine, namely: chromium, cadmium, nickel, 1-hydroxypyrene as a proxy for exposure to other carcinogenic polycyclic aromatic hydrocarbons (PAHs), t,t-muconic acid as a metabolite of benzene, 2,5-dichlorophenol (2,5-DCP), organophosphate pesticide metabolites, and di(2-ethylhexyl) phthalate (DEHP) metabolites. In blood, arsenic, polychlorinated biphenyl (PCB) congeners 118 and 156, hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (DDT) and perfluorooctanoic acid (PFOA) were analyzed. Levels of methylmercury (MeHg) were measured in hair. Multiple linear regression models were used to establish exposure-response relationships. Results: Biomarkers of exposure to PAHs and urinary chromium were associated with higher levels of both 8-OHdG in urine and DNA damage detected by the alkaline comet assay. Concentrations of 8-OHdG in urine increased in relation with increasing concentrations of urinary t,t-muconic acid, cadmium, nickel, 2,5-DCP, and DEHP metabolites. Increased concentrations of PFOA in blood were associated with higher levels of DNA damage measured by the alkaline comet assay, whereas DDT was associated in the same direction with the Fpg-modified comet assay. Inverse associations were observed between blood arsenic, hair MeHg, PCB 156 and HCB, and urinary 8-OHdG. The latter exposure biomarkers were also associated with higher fish intake. Urinary nickel

Impairment of aminopyrine clearance in aspirin-damaged canine gastric mucosa

International Nuclear Information System (INIS)

Miller, T.A.; Henagan, J.M.; Loy, T.M.

1983-01-01

Using an in vivo canine chambered stomach preparation, the clearance of [ 14 C]aminopyrine across mucosa when intravenously infused and the back-diffusion of this substance from gastric lumen to mucosa when topically applied to gastric epithelium were evaluated in aspirin-damaged gastric epithelium. In mucosa damaged by either 20 mM or 40 mM aspirin, the recovery of [ 14 C]aminopyrine, when topically mixed with acid (pH . 1.1) perfusate solution, was not significantly different from nondamaged control mucosa. In addition, the degree of ''trapping'' of this substance from back-diffusion was not different in damaged mucosa from that observed in nondamaged epithelium. In contrast, when [ 14 C]aminopyrine was intravenously infused, its clearance was significantly impaired in aspirin-damaged mucosa when compared with control studies, as evidenced by the increased ''trapping'' of this substance in injured epithelium. These findings indicate that movement of aminopyrine from plasma to gastric lumen is impaired in damaged epithelium, making the aminopyrine clearance technique an unreliable method to accurately measure absolute gastric blood flow in this experimental setting

Health effects of acid aerosols formed by atmospheric mixtures

International Nuclear Information System (INIS)

Kleinman, M.T.; Phalen, R.F.; Mautz, W.J.; Mannix, R.C.; McClure, T.R.; Crocker, T.T.

1989-01-01

Under ambient conditions, sulfur and nitrogen oxides can react with photochemical products and airborne particles to form acidic vapors and aerosols. Inhalation toxicological studies were conducted, exposing laboratory animals, at rest and during exercise, to multicomponent atmospheric mixtures under conditions favorable to the formation of acidic reaction products. Effects of acid and ozone mixtures on early and late clearance of insoluble radioactive particles in the lungs of rats appeared to be dominated by the oxidant component (i.e., the mixture did cause effects that were significantly different from those of ozone alone). Histopathological evaluations showed that sulfuric acid particles alone did not cause inflammatory responses in centriacinar units of rat lung parenchyma (expressed in terms of percent lesion area) but did cause significant damage (cell killing followed by a wave of cell replication) in nasal respiratory epithelium, as measured by uptake of tritiated thymidine in the DNA of replicating cells. Mixtures of ozone and nitrogen dioxide, which form nitric acid, caused significant inflammatory responses in lung parenchyma (in excess of effects seen in rats exposed to ozone alone), but did not damage nasal epithelium. Mixtures containing acidic sulfate particles, ozone, and nitrogen dioxide damaged both lung parenchyma and nasal epithelia. In rats exposed at rest, the response of the lung appeared to be dominated by the oxidant gas-phase components, while responses in the nose were dominated by the acidic particles. In rats exposed at exercise, however, mixtures of ozone and sulfuric acid particles significantly (2.5-fold) elevated the degree of lung lesion formation over that seen in rats exposed to ozone alone under an identical exercise protocol

Adaptive resolution simulation of an atomistic DNA molecule in MARTINI salt solution

NARCIS (Netherlands)

Zavadlav, J.; Podgornik, R.; Melo, M.n.; Marrink, S.j.; Praprotnik, M.

2016-01-01

We present a dual-resolution model of a deoxyribonucleic acid (DNA) molecule in a bathing solution, where we concurrently couple atomistic bundled water and ions with the coarse-grained MAR- TINI model of the solvent. We use our fine-grained salt solution model as a solvent in the inner shell

Untitled

African Journals Online (AJOL)

Meiosis: formation of male or female repro- duction cells (eggs or sperms). The chromo- some number of the species is halved (but reconstituted when the egg meets the sperm at fertilization). • Gene : basic hereditary unit (made up of. DeoxyriboNucleic Acid -DNA) which de- termines protein structure or RiboNucleic.

Ultraviolet-B Protective Effect of Flavonoids from Eugenia caryophylata on Human Dermal Fibroblast Cells.

Science.gov (United States)

Patwardhan, Juilee; Bhatt, Purvi

2015-10-01

The exposure of skin to ultraviolet-B (UV-B) radiations leads to deoxyribonucleic acid (DNA) damage and can induce production of free radicals which imbalance the redox status of the cell and lead to increased oxidative stress. Clove has been traditionally used for its analgesic, anti-inflammatory, anti-microbial, anti-viral, and antiseptic effects. To evaluate the UV-B protective activity of flavonoids from Eugenia caryophylata (clove) buds on human dermal fibroblast cells. Protective ability of flavonoid-enriched (FE) fraction of clove was studied against UV-B induced cytotoxicity, anti-oxidant regulation, oxidative DNA damage, intracellular reactive oxygen species (ROS) generation, apoptotic morphological changes, and regulation of heme oxygenase-1 (HO-1) gene through nuclear factor E2-related factor 2 antioxidant response element (Nrf2 ARE) pathway. FE fraction showed a significant antioxidant potential. Pretreatment of cells with FE fraction (10-40 μg/ml) reversed the effects of UV-B induced cytotoxicity, depletion of endogenous enzymatic antioxidants, oxidative DNA damage, intracellular ROS production, apoptotic changes, and overexpression of Nrf2 and HO-1. The present study demonstrated for the first time that the FE fraction from clove could confer UV-B protection probably through the Nrf2-ARE pathway, which included the down-regulation of Nrf2 and HO-1. These findings suggested that the flavonoids from clove could potentially be considered as UV-B protectants and can be explored further for its topical application to the area of the skin requiring protection. Pretreatment of human dermal fibroblast with flavonoid-enriched fraction of Eugenia caryophylata attenuated effects of ultraviolet-B radiationsIt also conferred protection through nuclear factor E2-related factor 2-antioxidant response pathway and increased tolerance of cells against oxidative stressFlavonoid-enriched fraction can be explored further for topical application to the skin as a

Restoration of dioxin-induced damage to fetal steroidogenesis and gonadotropin formation by maternal co-treatment with α-lipoic acid.

Directory of Open Access Journals (Sweden)

Takayuki Koga

Full Text Available 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD, an endocrine disruptor, causes reproductive and developmental toxic effects in pups following maternal exposure in a number of animal models. Our previous studies have demonstrated that TCDD imprints sexual immaturity by suppressing the expression of fetal pituitary gonadotropins, the regulators of gonadal steroidogenesis. In the present study, we discovered that all TCDD-produced damage to fetal production of pituitary gonadotropins as well as testicular steroidogenesis can be repaired by co-treating pregnant rats with α-lipoic acid (LA, an obligate co-factor for intermediary metabolism including energy production. While LA also acts as an anti-oxidant, other anti-oxidants; i.e., ascorbic acid, butylated hydroxyanisole and edaravone, failed to exhibit any beneficial effects. Neither wasting syndrome nor CYP1A1 induction in the fetal brain caused through the activation of aryl hydrocarbon receptor (AhR could be attenuated by LA. These lines of evidence suggest that oxidative stress makes only a minor contribution to the TCDD-induced disorder of fetal steroidogenesis, and LA has a restorative effect by targeting on mechanism(s other than AhR activation. Following a metabolomic analysis, it was found that TCDD caused a more marked change in the hypothalamus, a pituitary regulator, than in the pituitary itself. Although the components of the tricarboxylic acid cycle and the ATP content of the fetal hypothalamus were significantly changed by TCDD, all these changes were again rectified by exogenous LA. We also provided evidence that the fetal hypothalamic content of endogenous LA is significantly reduced following maternal exposure to TCDD. Thus, the data obtained strongly suggest that TCDD reduces the expression of fetal pituitary gonadotropins to imprint sexual immaturity or disturb development by suppressing the level of LA, one of the key players serving energy production.

Quantification of DNA damage by single-cell electrophoresis

International Nuclear Information System (INIS)

Ikushima, Takaji

1990-01-01

A simple technique of micro-agarose gel electrophoresis has been developed to quantify DNA damage in individual cells. Cells are embedded in agarose gel on microscope slides, lysed by detergents and then electrophoresed for a short time under neutral or alkaline condition. In irradiated cells, DNA migrates from the nucleus toward the anode, displaying commet-like pattern by staining with DNA-specific fluorescence dye. DNA damage is evaluated by measuring the distance of DNA migration. The technique was applied for measuring DNA damage in single cells exposed to 60 Co γ-rays, or to KUR radiation in the presence or absence of 10 B-enriched boric acid. The enhanced production of double-stranded DNA breaks by 10 B(n,α) 7 Li reaction was demonstrated here. The significant increase in the length of DNA migration was observed in single cells exposed to such a low dose as 20 cGy after alkaline micro electrophoresis. (author)

The Effects of Adding Whey Protein and Branched-chain Amino Acid to Carbohydrate Beverages on Indices of Muscle Damage after Eccentric Resistance Exercise in Untrained Young Males

OpenAIRE

Foad Asjodi; Hamid Mohebi; Ebrahim Mirzajani; Azimeh Izadi

2017-01-01

Abstract Background: The aim of this study was to evaluate the effects of supplementation of Branched-Chain Amino Acids (BCAAs) plus carbohydrate (CHO) and whey protein plus CHO on muscle damage indices after eccentric resistant exercise. Materials and Methods: Twenty four untrained healthy males participated in this study. They were randomly divided into three groups, BCAA +glucose (0.1+0.1g/kg) supplement group (n=8), Whey+glucose (0.1+0.1g/kg) supplement group (n=8), and placebo (ma...

Videodensitometry in rats with pulmonary damage due to microembolism

Energy Technology Data Exchange (ETDEWEB)

Wegenius, G.; Wegener, T.; Ruhn, G.; Saldeen, T.; Erikson, U.

Serial pulmonary angiography with videodensitometry was performed in 18 rats with pulmonary damage caused by administration of a fibrinolysis inhibitor, tranexamic acid (200 mg/kg body weight injected intraperitoneally) and bovine thrombin (500 NIH/kg body weight injected into the right femoral vein). The mean transit time (MTT) was calculated from videodensitometry, the observed area of interest consisting of approximately one-third of the right lung, including both central and peripheral parts. The impact of the pulmonary damage was analysed by morphologic methods and correlated to MTT. Although a pressure rise presumably occurred in the pulmonary circulation, no change in MTT was found after induction of pulmonary damage, indicating opening of actual and potential anastomoses between pulmonary arterioles and venules to serve as by-pass portions and as a safety-valve mechanism for the capillary bed and the right heart, respectively. Another explanation to unchanged MTT may be opening of resting capillary beds. Two rats with very severe pulmonary damage showed prolonged MTT. These rats may have suffered from cardiac failure.

Videodensitometry in rats with pulmonary damage due to microembolism

International Nuclear Information System (INIS)

Wegenius, G.; Wegener, T.; Ruhn, G.; Saldeen, T.; Erikson, U.

1985-01-01

Serial pulmonary angiography with videodensitometry was performed in 18 rats with pulmonary damage caused by administration of a fibrinolysis inhibitor, tranexamic acid (200 mg/kg body weight injected intraperitoneally) and bovine thrombin (500 NIH/kg body weight injected into the right femoral vein). The mean transit time (MTT) was calculated from videodensitometry, the observed area of interest consisting of approximately one-third of the right lung, including both central and peripheral parts. The impact of the pulmonary damage was analysed by morphologic methods and correlated to MTT. Although a pressure rise presumably occurred in the pulmonary circulation, no change in MTT was found after induction of pulmonary damage, indicating opening of actual and potential anastomoses between pulmonary arterioles and venules to serve as by-pass portions and as a safety-valve mechanism for the capillary bed and the right heart, respectively. Another explanation to unchanged MTT may be opening of resting capillary beds. Two rats with very severe pulmonary damage showed prolonged MTT. These rats may have suffered from cardiac failure. (orig.)

Biochemical reasoning for radiation protection and screening methods for radiation sensitivity and potential carcinogenicity

International Nuclear Information System (INIS)

Riklis, Emanuel; Emerit, Ingrid

1994-01-01

Cells of different genetic characteristics respond differently to agents that modify radiation effects. When the modification is a result of chemical repair, reduction of the amount of damage by radical scavenging, production of hypoxia, or any other such mechanism, then the modification of the response will be the same for all types of cells, but not the same when biological or biochemical parameters are involved, because the differences between the cells affect the final outcome, and the genetic traits obviously become affected by chemical modifying agents. Some of these agents directly affect the repair of deoxyribonucleic acid (DNA) by mechanisms not yet understood. Another agent nicotinamide (NA), is directly linked to a repair pathway. Thus, a system that uses NA as a precursor of nicotinamide adenine dinucleotide (NAD) + , and uses NAD + to produce the polymer polyadenosine diphosphate ribose (PADPR) appears to be an interesting and important factor in the biochemical events that may be linked to improved radioprotection. (author). 36 refs., 5 figs

DNA fragmentation dynamics allows the assessment of cryptic sperm damage in human: Evaluation of exposure to ionizing radiation, hyperthermia, acidic pH and nitric oxide

Energy Technology Data Exchange (ETDEWEB)

Santiso, Rebeca; Tamayo, Maria [Laboratorio de Genetica Molecular y Radiobiologia, Centro Oncologico de Galicia, Doctor Camilo Veiras 1, 15009-A Coruna (Spain); Genetics Unit, INIBIC-Complejo Hospitalario Universitario A Coruna (CHUAC), As Xubias, 84, 15006-A Coruna (Spain); Gosalvez, Jaime [Genetics Unit, Facultad de Biologia, Universidad Autonoma de Madrid, Ciudad Universitaria de Cantoblanco, 28049 Madrid (Spain); Johnston, Steve [School of Agriculture and Food Science, University of Queensland, Gatton 4343 (Australia); Marino, Alfonso [Servicio de Oncologia Radioterapica, Centro Oncologico de Galicia, Doctor Camilo Veiras 1, 15009-A Coruna (Spain); Fernandez, Carlos; Losada, Carlos [Servicio de Radiofisica, Centro Oncologico de Galicia, Doctor Camilo Veiras 1, 15009-A Coruna (Spain); Fernandez, Jose Luis, E-mail: Jose.Luis.Fernandez.Garcia@sergas.es [Laboratorio de Genetica Molecular y Radiobiologia, Centro Oncologico de Galicia, Doctor Camilo Veiras 1, 15009-A Coruna (Spain); Genetics Unit, INIBIC-Complejo Hospitalario Universitario A Coruna (CHUAC), As Xubias, 84, 15006-A Coruna (Spain)

2012-06-01

Sperm DNA fragmentation (SDF) is not a static seminal parameter, since the longevity of sperm DNA decreases progressively with time following ejaculation or thawing. While the dynamics of SDF is a species-specific characteristic, in the case of humans, there is still significant variation within patients. To evaluate the suitability of the dynamic SDF assay to assess the adverse effects of agents that cause genetic damage, fresh semen samples from different donors were exposed in vitro to (1) increasing acute doses of ionizing radiation, (2) elevated temperature (41 Degree-Sign C and 45 Degree-Sign C), (3) acidic pH (pH 4) and (4) the nitric oxide (NO) donor sodium nitroprusside (SNP). Sperm DNA fragmentation was analyzed after an incubation period of chronic (24 h), or acute (1 h) exposure to each treatment followed by incubation at 37 Degree-Sign C over a period of 24 h. SDF was assessed using the sperm chromatin dispersion (SCD) test. Dynamic SDF for each treatment was analyzed using Kaplan-Meier survival curves. All agents, except for ionizing radiation, accelerated SDF kinetics following chronic exposure over a 24 h period. Transient exposure to NO and heat but not acidic pH increased the basal (T0) level of SDF. Despite the removal of the three toxicants, the remaining sperm following acute exposure showed a decrease in their expected DNA longevity. It is concluded that the assessment of sperm DNA fragmentation dynamics is an effective methodological approach for revealing latent damage associated with toxicants that is not initially expressed following a single initial observation of SDF.

Bile acids: regulation of apoptosis by ursodeoxycholic acid.

Science.gov (United States)

Amaral, Joana D; Viana, Ricardo J S; Ramalho, Rita M; Steer, Clifford J; Rodrigues, Cecília M P

2009-09-01

Bile acids are a group of molecular species of acidic steroids with peculiar physical-chemical and biological characteristics. At high concentrations they become toxic to mammalian cells, and their presence is pertinent in the pathogenesis of several liver diseases and colon cancer. Bile acid cytoxicity has been related to membrane damage, but also to nondetergent effects, such as oxidative stress and apoptosis. Strikingly, hydrophilic ursodeoxycholic acid (UDCA), and its taurine-conjugated form (TUDCA), show profound cytoprotective properties. Indeed, these molecules have been described as potent inhibitors of classic pathways of apoptosis, although their precise mode of action remains to be clarified. UDCA, originally used for cholesterol gallstone dissolution, is currently considered the first choice therapy for several forms of cholestatic syndromes. However, the beneficial effects of both UDCA and TUDCA have been tested in other experimental pathological conditions with deregulated levels of apoptosis, including neurological disorders, such as Alzheimer's, Parkinson's, and Huntington's diseases. Here, we review the role of bile acids in modulating the apoptosis process, emphasizing the anti-apoptotic effects of UDCA and TUDCA, as well as their potential use as novel and alternate therapeutic agents for the treatment of apoptosis-related diseases.

Deoxyribonucleic acid directed metallization of platinum nanoparticles on graphite nanofibers as a durable oxygen reduction catalyst for polymer electrolyte fuel cells

Science.gov (United States)

Peera, S. Gouse; Sahu, A. K.; Arunchander, A.; Nath, Krishna; Bhat, S. D.

2015-11-01

Effective surface functionalization to the hydrophobic graphite nanofibers (GNF) is performed with the biomolecule, namely deoxy-ribo-nucleic-acid (DNA) via π-π interactions. Pt nanoparticles are impregnated on GNF-DNA composite by ethylene glycol reduction method (Pt/GNF-DNA) and its effect on electro catalytic activity for oxygen reduction reaction (ORR) is systemically studied. Excellent dispersion of Pt nanoparticles over GNF-DNA surfaces with no evidence on particle aggregation is a remarkable achievement in this study. This result in higher electro chemical surface area of the catalyst, enhanced ORR behavior with significant enhancement in mass activity. The catalyst is validated in H2-O2 polymer electrolyte fuel cell (PEFC) and a peak power density of 675 mW cm-2 is achieved at a load current density of 1320 mA cm-2 with a minimal catalyst loading of 0.1 mg cm-2 at a cell temperature of 70 °C and 2 bar absolute pressure. Repeated potential cycling up to 10000 cycles in acidic media is also performed for this catalyst and found excellent stability with only 60 mV drop in the ORR half wave potential. The superior behavior of Pt/GNF-DNA catalyst is credited to the robust fibrous structure of GNF and its effective surface functionalization process via π-π interaction.

Response of plasma membrane H+-ATPase in rice (Oryza sativa) seedlings to simulated acid rain.

Science.gov (United States)

Liang, Chanjuan; Ge, Yuqing; Su, Lei; Bu, Jinjin

2015-01-01

Understanding the adaptation of plants to acid rain is important to find feasible approaches to alleviate such damage to plants. We studied effects of acid rain on plasma membrane H(+)-ATPase activity and transcription, intracellular H(+), membrane permeability, photosynthetic efficiency, and relative growth rate during stress and recovery periods. Simulated acid rain at pH 5.5 did not affect plasma membrane H(+)-ATPase activity, intracellular H(+), membrane permeability, photosynthetic efficiency, and relative growth rate. Plasma membrane H(+)-ATPase activity and transcription in leaves treated with acid rain at pH 3.5 was increased to maintain ion homeostasis by transporting excessive H(+) out of cells. Then intracellular H(+) was close to the control after a 5-day recovery, alleviating damage on membrane and sustaining photosynthetic efficiency and growth. Simulated acid rain at pH 2.5 inhibited plasma membrane H(+)-ATPase activity by decreasing the expression of H(+)-ATPase at transcription level, resulting in membrane damage and abnormal intracellular H(+), and reduction in photosynthetic efficiency and relative growth rate. After a 5-day recovery, all parameters in leaves treated with pH 2.5 acid rain show alleviated damage, implying that the increased plasma membrane H(+)-ATPase activity and its high expression were involved in repairing process in acid rain-stressed plants. Our study suggests that plasma membrane H(+)-ATPase can play a role in adaptation to acid rain for rice seedlings.

Physiological and metabolic effects of 5-aminolevulinic acid for mitigating salinity stress in creeping bentgrass.

Directory of Open Access Journals (Sweden)

Zhimin Yang

Full Text Available The objectives of this study were to determine whether foliar application of a chlorophyll precursor, 5-aminolevulinic acid (ALA, could mitigate salinity stress damages in perennial grass species by regulating photosynthetic activities, ion content, antioxidant metabolism, or metabolite accumulation. A salinity-sensitive perennial grass species, creeping bentgrass (Agrostis stolonifera, was irrigated daily with 200 mM NaCl for 28 d, which were foliar sprayed with water or ALA (0.5 mg L-1 weekly during the experiment in growth chamber. Foliar application of ALA was effective in mitigating physiological damage resulting from salinity stress, as manifested by increased turf quality, shoot growth rate, leaf relative water content, chlorophyll content, net photosynthetic rate, stomatal conductance and transpiration rate. Foliar application of ALA also alleviated membrane damages, as shown by lower membrane electrolyte leakage and lipid peroxidation, which was associated with increases in the activities of antioxidant enzymes. Leaf content of Na+ was reduced and the ratio of K+/Na+ was increased with ALA application under salinity stress. The positive effects of ALA for salinity tolerance were also associated with the accumulation of organic acids (α-ketoglutaric acid, succinic acid, and malic acid, amino acids (alanine, 5-oxoproline, aspartic acid, and γ -aminobutyric acid, and sugars (glucose, fructose, galactose, lyxose, allose, xylose, sucrose, and maltose. ALA-mitigation of physiological damages by salinity could be due to suppression of Na+ accumulation and enhanced physiological and metabolic activities related to photosynthesis, respiration, osmotic regulation, and antioxidant defense.

Deoxycholic Acid and the Marginal Mandibular Nerve: A Cadaver Study.

Science.gov (United States)

Blandford, Alexander D; Ansari, Waseem; Young, Jason M; Maley, Bruce; Plesec, Thomas P; Hwang, Catherine J; Perry, Julian D

2018-06-04

One of the rare but serious complications observed with deoxycholic acid administration is damage to the marginal mandibular nerve. In this study, we evaluated if deoxycholic acid directly induces histologic damage to fresh cadaveric marginal mandibular nerve. A segment of marginal mandibular nerve was harvested from 12 hemifaces of 6 fresh cadavers. The nerve specimen was exposed to either 0.9% sterile saline for 24 h, deoxycholic acid (10 mg/ml) for 20 min, or deoxycholic acid (10 mg/ml) for 24 h. The nerve specimens were then fixed in glutaraldehyde for a minimum of 24 h. Toluidine blue stained sections were evaluated for stain intensity using light microscopy and color deconvolution image analysis. Supraplatysmal fat was harvested as a positive control and exposed to the same treatments as the marginal mandibular nerve specimens, then evaluated using transmission electron microscopy. Toluidine blue staining was less in the marginal mandibular nerve exposed to deoxycholic acid when compared to saline. The specimen exposed to deoxycholic acid for 24 h showed less toluidine blue staining than that of the nerve exposed to deoxycholic acid for 20 min. Transmission electron microscopy of submental fat exposed to deoxycholic acid revealed disruption of adipocyte cell membrane integrity and loss of cellular organelles when compared to specimens only exposed to saline. Deoxycholic acid (10 mg/ml) damages the marginal mandibular nerve myelin sheath in fresh human cadaver specimens. Direct deoxycholic acid neurotoxicity may cause marginal mandibular nerve injury clinically. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Agmatine protects Müller cells from high-concentration glucose-induced cell damage via N-methyl-D-aspartic acid receptor inhibition.

Science.gov (United States)

Han, Ning; Yu, Li; Song, Zhidu; Luo, Lifu; Wu, Yazhen

2015-07-01

Neural injury is associated with the development of diabetic retinopathy. Müller cells provide structural and metabolic support for retinal neurons. High glucose concentrations are known to induce Müller cell activity. Agmatine is an endogenous polyamine, which is enzymatically formed in the mammalian brain and has exhibited neuroprotective effects in a number of experimental models. The aims of the present study were to investigate whether agmatine protects Müller cells from glucose-induced damage and to explore the mechanisms underlying this process. Lactate dehydrogenase activity and tumor necrosis factor-α mRNA expression were significantly reduced in Müller cells exposed to a high glucose concentration, following agmatine treatment, compared with cells not treated with agmatine. In addition, agmatine treatment inhibited glucose-induced Müller cell apoptosis, which was associated with the regulation of Bax and Bcl-2 expression. Agmatine treatment suppressed glucose-induced phosphorylation of mitogen-activated protein kinase (MAPK) protein in Müller cells. The present study demonstrated that the protective effects of agmatine on Müller cells were inhibited by N-methyl-D-aspartic acid (NMDA). The results of the present study suggested that agmatine treatment protects Müller cells from high-concentration glucose-induced cell damage. The underlying mechanisms may relate to the anti-inflammatory and antiapoptotic effects of agmatine, as well as to the inhibition of the MAPK pathway, via NMDA receptor suppression. Agmatine may be of use in the development of novel therapeutic approaches for patients with diabetic retinopathy.

The Protective Effect of Whole Honey and Phenolic Extract on Oxidative DNA Damage in Mice Lymphocytes Using Comet Assay.

Science.gov (United States)

Cheng, Ni; Wang, Yuan; Cao, Wei

2017-12-01

In this study, the antioxidant activity and the protective effect against hydrogen peroxide-induced DNA damage were assessed for five honeys of different botanical origin. Seven phenolic acids were detected in the honey samples. Ferulic acid was the most abundant phenolic acid detected in longan honey, jujube honey and buckwheat honey. Ellagic acid, p-hydroxybenzoic acid and protocatechuic acid were the main phenolic acids detected in vitex honey. Of all honey samples tested, the highest total phenolic content and antioxidant activity were found in buckwheat honey, whereas the lowest total phenolic content and antioxidant activity were found in locust honey. Treatment with hydrogen peroxide induced a 62% increase in tail DNA in mice lymphocytes, and all studied honeys significantly inhibited this effect (P Phenolic extracts of honey displayed greater protective effects than whole honey in comet assay. The hydrogen peroxide-generated increase in 8-hydroxy-2-deoxyguanosine (8-OHdG) was effectively inhibited by the honeys studied (P phenolic acids of honey can penetrate into lymphocytes and protect DNA from oxidative damage by scavenging hydrogen peroxide and/or chelating ferrous ions.

Damage cross sections for fast heavy ion induced desorption of biomolecules

Energy Technology Data Exchange (ETDEWEB)

Salehpour, M; Hakansson, P; Sundqvist, B [Uppsala Univ. (Sweden). Tandem Accelerator Lab.

1984-03-01

The Uppsala EN-tandem accelerator combined with a time-of-flight mass spectrometer has been used to measure the damage cross sections for Fast Heavy Ion Induced Desorption (FHIID) of the amino acid valine (MW=117) and the protein bovine insulin (MW=5733). Time-of-flight spectra have been obtained after exposing the sample to a known radiation dose of 90 MeV /sup 127/I/sup 14 +/ ions and the yield of the quasi-molecular ions has been measured as a function of the radiation dose. The results are: 6.8(+-1.8)x10/sup -13/ cm/sup 2/ and 50(+-17)x10/sup -13/ cm/sup 2/ for positive ions of valine and insulin respectively. The cross section for valine is roughly one order of magnitude larger than previously published low energy (keV) damage cross sections for the amino acid leucine.

Impact of lymphoma treatments on spermatogenesis and sperm deoxyribonucleic acid: a multicenter prospective study from the CECOS network.

Science.gov (United States)

Bujan, Louis; Walschaerts, Marie; Brugnon, Florence; Daudin, Myriam; Berthaut, Isabelle; Auger, Jacques; Saias, Jacqueline; Szerman, Ethel; Moinard, Nathalie; Rives, Nathalie; Hennebicq, Sylvianne

2014-09-01

To determine consequences of lymphoma treatments on sperm characteristics and sperm DNA, and to evaluate predictors of sperm recovery. Multicenter prospective longitudinal study of patients analyzed before treatment and after 3, 6, 12, and 24 months. University hospitals. Seventy-five Hodgkin lymphoma and non-Hodgkin lymphoma patients and a control group of 257 fertile men. Semen analyses, and sperm DNA and chromatin assessments. Comparisons of sperm characteristics before and after treatment. Patients already had altered sperm characteristics before lymphoma treatment, with no identified risk factor. Sperm count, total sperm count, motility, and vitality decreased after treatment, with lowest values at 3 and 6 months. Twelve months after treatment, mean sperm count recovered to pretreatment values after doxorubicin, bleomycin, vinblastine, darcarbacine (ABVD) or ABVD+radiotherapy, but not after doxorubicin, cyclophosphamide, vincristine, prednisone (CHOP) or mechlorethamine, oncovin, procarbazine, prednisone (MOPP) chemotherapies. It was noteworthy that 7% of patients remained azoospermic at 24 months. After 24 months, Kaplan-Meier estimates showed that more than 90% of patients will recover normal sperm count after ABVD or ABVD+radiotherapy vs. 61% for CHOP chemotherapies. In multivariate analyses including diagnosis and treatment protocol, only pretreatment total sperm count was related to recovery. Compared with a control group, lymphoma patients had higher sperm chromatin alterations and DNA fragmentation before any treatment. After treatment, DNA fragmentation assessed by TUNEL assay and sperm chromatin structure assay decreased from 3 and 6 months, respectively, while remaining higher than in the control group during follow-up. Lymphoma patients had altered sperm DNA and chromatin before treatment. Lymphoma treatment had damaging effects on spermatogenesis. These data on both the recovery period according to treatment modalities and the pre- and post

Exponential Increase in Relative Biological Effectiveness Along Distal Edge of a Proton Bragg Peak as Measured by Deoxyribonucleic Acid Double-Strand Breaks

Energy Technology Data Exchange (ETDEWEB)

Cuaron, John J., E-mail: cuaronj@mskcc.org [Memorial Sloan Kettering Cancer Center, New York, New York (United States); Chang, Chang [Texas Center for Proton Therapy, Irving, Texas (United States); Lovelock, Michael; Higginson, Daniel S. [Memorial Sloan Kettering Cancer Center, New York, New York (United States); Mah, Dennis [Procure Proton Therapy Center, Somerset, New Jersey (United States); Cahlon, Oren; Powell, Simon [Memorial Sloan Kettering Cancer Center, New York, New York (United States)

2016-05-01

Purpose: To quantify the relative biological effectiveness (RBE) of the distal edge of the proton Bragg peak, using an in vitro assay of DNA double-strand breaks (DSBs). Methods and Materials: U2OS cells were irradiated within the plateau of a spread-out Bragg peak and at each millimeter position along the distal edge using a custom slide holder, allowing for simultaneous measurement of physical dose. A reference radiation signal was generated using photons. The DNA DSBs at 3 hours (to assess for early damage) and at 24 hours (to assess for residual damage and repair) after irradiation were measured using the γH2AX assay and quantified via flow cytometry. Results were confirmed with clonogenic survival assays. A detailed map of the RBE as a function of depth along the Bragg peak was generated using γH2AX measurements as a biological endpoint. Results: At 3 hours after irradiation, DNA DSBs were higher with protons at every point along the distal edge compared with samples irradiated with photons to similar doses. This effect was even more pronounced after 24 hours, indicating that the impact of DNA repair is less after proton irradiation relative to photons. The RBE demonstrated an exponential increase as a function of depth and was measured to be as high as 4.0 after 3 hours and as high as 6.0 after 24 hours. When the RBE-corrected dose was plotted as a function of depth, the peak effective dose was extended 2-3 mm beyond what would be expected with physical measurement. Conclusions: We generated a highly comprehensive map of the RBE of the distal edge of the Bragg peak, using a direct assay of DNA DSBs in vitro. Our data show that the RBE of the distal edge increases with depth and is significantly higher than previously reported estimates.

Research Advances: DNA Computing Targets West Nile Virus, Other Deadly Diseases, and Tic-Tac-Toe; Marijuana Component May Offer Hope for Alzheimer's Disease Treatment; New Wound Dressing May Lead to Maggot Therapy--Without the Maggots

Science.gov (United States)

King, Angela G.

2007-01-01

This article presents three reports of research advances. The first report describes a deoxyribonucleic acid (DNA)-based computer that could lead to faster, more accurate tests for diagnosing West Nile Virus and bird flu. Representing the first "medium-scale integrated molecular circuit," it is the most powerful computing device of its type to…

Expression of VP60 gene from rabbit haemorrhagic disease virus ...

African Journals Online (AJOL)

The VP60 gene from rabbit haemorrhagic disease virus (RHDV) YL strain in Northeast of China, under control of the ats1A promoter from Rubisco small subunit genes of Arabidopsis thaliana, was introduced into the transfer deoxyribonucleic acid (T-DNA) region of plant transfer vector pCAMBIA1300 and transferred to ...

Synthesis, Characterization and DNA Cleavage of Copper(II ...

African Journals Online (AJOL)

Purpose: To study deoxyribonucleic acid (DNA) shearing capability of copper(II) complex of dithiothreitol (DTT) and to fevaluate its potential application in cancer therapy. Methods: A parrot green complex was synthesized by grinding copper acetate monohydrate and DTT in 1:2 molar ratio in a mortar until no fumes of acetic ...

Restoration of Radiation-Induced Damage Related to the Cell Cycle

Energy Technology Data Exchange (ETDEWEB)

Petrovic, D.; Ferle-Vidovic, Ana [Institute Ruder Boskovic, Zagreb, Yugoslavia (Croatia)

1968-08-15

A restorative effect of DNA and its precursors in asynchronously growing L-cells after X-irradiation had previously been found. The fact that the precursors were active only if all four of them were added in the form of an equimolar solution, as well as some other d ata, indicated that such treatment might support certain repair processes in the damaged metabolism of nucleic acids. To obtain more information on this problem, synchronized populations of L-cells were irradiated at different stages of the cell cycle with 500 R of X-rays and then treated with either highly polymerized DNA or with nucleotides or nucleosides. The survival of the treated and untreated cells was then calculated and compared. It was found that the cells were over ten times more sensitive in the DNA-synthetic (S) period than in the presynthetic (G{sub 1}) period. The restorative effect of all three materials was related to the S period. The highly polymerized DNA and the deoxytibonucleosides were much more effective than the deoxyribonucleotides. The results indicate that the influence of small molecules and the role they play in the damaged metabolism of nucleic acids could be of considerable importance in the mechanism of the restorative effect produced by nucleic-acid treatment. (author)

Uric acid in multiple sclerosis

NARCIS (Netherlands)

Koch, M; De Keyser, J

Peroxynitrite, a reactive oxidant formed by the reaction of nitric oxide with superoxide at sites of inflammation in multiple sclerosis (MS), is capable of damaging tissues and cells. Uric acid, a natural scavenger of peroxynitrite, reduces inflammatory demyelination in experimental allergic

Clinical Study of Ursodeoxycholic Acid in Barrett's Esophagus Patients.

Science.gov (United States)

Banerjee, Bhaskar; Shaheen, Nicholas J; Martinez, Jessica A; Hsu, Chiu-Hsieh; Trowers, Eugene; Gibson, Blake A; Della'Zanna, Gary; Richmond, Ellen; Chow, H-H Sherry

2016-07-01

Prior research strongly implicates gastric acid and bile acids, two major components of the gastroesophageal refluxate, in the development of Barrett's esophagus and its pathogenesis. Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, has been shown to protect esophageal cells against oxidative stress induced by cytotoxic bile acids. We conducted a pilot clinical study to evaluate the clinical activity of UDCA in patients with Barrett's esophagus. Twenty-nine patients with Barrett's esophagus received UDCA treatment at a daily dose of 13 to 15 mg/kg/day for 6 months. The clinical activity of UDCA was assessed by evaluating changes in gastric bile acid composition and markers of oxidative DNA damage (8-hydroxydeoxyguanosine), cell proliferation (Ki67), and apoptosis (cleaved caspase-3) in Barrett's esophagus epithelium. The bile acid concentrations in gastric fluid were measured by liquid chromatography/mass spectrometry. At baseline, UDCA (sum of unchanged and glycine/taurine conjugates) accounted for 18.2% of total gastric bile acids. After UDCA intervention, UDCA increased significantly to account for 93.4% of total gastric bile acids (P acid composition but did not modulate selected markers of oxidative DNA damage, cell proliferation, and apoptosis in the Barrett's esophagus epithelium. Cancer Prev Res; 9(7); 528-33. ©2016 AACRSee related article by Brian J. Reid, p. 512. ©2016 American Association for Cancer Research.

Neuroprotective actions of taurine on hypoxic-ischemic brain damage in neonatal rats.

Science.gov (United States)

Zhu, Xiao-Yun; Ma, Peng-Sheng; Wu, Wei; Zhou, Ru; Hao, Yin-Ju; Niu, Yang; Sun, Tao; Li, Yu-Xiang; Yu, Jian-Qiang

2016-06-01

Taurine is an abundant amino acid in the nervous system, which has been proved to possess antioxidation, osmoregulation and membrane stabilization. Previously it has been demonstrated that taurine exerts ischemic brain injury protective effect. This study was designed to investigate whether the protective effect of taurine has the possibility to be applied to treat neonatal hypoxic-ischemic brain damage. Seven-day-old Sprague-Dawley rats were treated with left carotid artery ligation followed by exposure to 8% oxygen to generate the experimental group. The cerebral damage area was measured after taurine post-treatment with 2,3,5-triphenyltetrazolium chloride (TTC) staining, Hematoxyline-Eosin (HE) staining and Nissl staining. The activities of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), myeloperoxtidase (MPO), ATP and Lactic Acid productions were assayed with ipsilateral hemisphere homogenates. Western-blot and immunofluorescence assay were processed to detect the expressions of AIF, Cyt C, Bax, Bcl-2 in brain. We found that taurine significantly reduced brain infarct volume and ameliorated morphological injury obviously reversed the changes of SOD, MDA, GSH-Px, T-AOC, ATP, MPO, and Lactic Acid levels. Compared with hypoxic-ischemic group, it showed marked reduction of AIF, Cyt C and Bax expressions and increase of Bcl-2 after post-treatment. We conclude that taurine possesses an efficacious neuroprotective effect after cerebral hypoxic-ischemic damage in neonatal rats. Copyright © 2016 Elsevier Inc. All rights reserved.

Genetic and environmental influences on oxidative damage assessed in elderly Danish twins

DEFF Research Database (Denmark)

Broedbaek, Kasper; Ribel-Madsen, Rasmus; Henriksen, Trine

2011-01-01

Previous studies have shown an association between oxidative stress and various diseases in humans including cancer, cardiovascular disease, diabetes, and chronic respiratory disease. To what extents this damage is determined by genetic and environmental factors is unknown. In a classical twin...... of oxidative stress were closely correlated (r=0.60-0.84). In conclusion, we demonstrated in a large population of elderly Danish twins that "whole-body" oxidative damage to nucleic acids and lipids is predominantly determined by potentially modifiable nongenetic factors....

Protective effect of 3,4-dihydroxybenzoic acid isolated from Cladophora wrightiana Harvey against ultraviolet B radiation-induced cell damage in human HaCaT keratinocytes.

Science.gov (United States)

Cha, Ji Won; Piao, Mei Jing; Kim, Ki Cheon; Zheng, Jian; Yao, Cheng Wen; Hyun, Chang Lim; Kang, Hee Kyoung; Yoo, Eun Sook; Koh, Young Sang; Lee, Nam Ho; Ko, Mi Hee; Hyun, Jin Won

2014-03-01

The aim of the present study was to elucidate the protective properties of 3,4-dihydroxybenzoic acid (DBA) isolated from Cladophora wrightiana Harvey (a green alga) against ultraviolet B (UVB)-induced damage to human HaCaT keratinocytes. DBA exhibited scavenging actions against the 1,1-diphenyl-2-picrylhydrazyl radical, the superoxide anion, and the hydroxyl radical. Furthermore, DBA decreased the levels of intracellular reactive oxygen species generated by hydrogen peroxide or UVB treatment of the cells. DBA also decreased the UVB-augmented levels of phospho-histone H2A.X and the extent of comet tail formation, which are both indications of DNA damage. In addition, the compound safeguarded keratinocytes from UVB-induced injury by reversing the production of apoptotic bodies, overturning the disruption of mitochondrial membrane potential, increasing the expression of the anti-apoptotic protein, B-cell lymphoma 2, and decreasing the expression of the pro-apoptotic proteins, Bcl-2-associated X and cleaved caspase-3. Taken together, these results demonstrate that DBA isolated from a green alga protects human keratinocytes against UVB-induced oxidative stress and apoptosis.

Effect of seven Indian plant extracts on Fenton reaction-mediated damage to DNA constituents.

Science.gov (United States)

Kar, Indrani; Chattopadhyaya, Rajagopal

2017-11-01

The influences of substoichiometric amounts of seven plant extracts in the Fenton reaction-mediated damage to deoxynucleosides, deoxynucleoside monophosphates, deoxynucleoside triphosphates, and supercoiled plasmid DNA were studied to rationalize anticancer properties reported in some of these extracts. Extracts from Acacia catechu, Emblica officinalis, Spondias dulcis, Terminalia belerica, Terminalia chebula, as well as gallic acid, epicatechin, chebulagic acid and chebulinic acid enhance the extent of damage in Fenton reactions with all monomeric substrates but protect supercoiled plasmid DNA, compared to standard Fenton reactions. The damage to pyrimidine nucleosides/nucleotides is enhanced by these extracts and compounds to a greater extent than for purine ones in a concentration dependent manner. Dolichos biflorus and Hemidesmus indicus extracts generally do not show this enhancement for the monomeric substrates though they protect plasmid DNA. Compared to standard Fenton reactions for deoxynucleosides with ethanol, the presence of these five plant extracts render ethanol scavenging less effective as the radical is generated in the vicinity of the target. Since substoichiometric amounts of these extracts and the four compounds produce this effect, a catalytic mechanism involving the presence of a ternary complex of the nucleoside/nucleotide substrate, a plant compound and the hydroxyl radical is proposed. Such a mechanism cannot operate for plasmid DNA as the planar rings in the extract compounds cannot stack with the duplex DNA bases. These plant extracts, by enhancing Fenton reaction-mediated damage to deoxynucleoside triphosphates, slow down DNA replication in rapidly dividing cancer cells, thus contributing to their anticancer properties.

Mechanisms of DNA damage by the tumor promoter and progressor benzoyl peroxide

International Nuclear Information System (INIS)

Swauger, J.E.; Dolan, P.M.; Zweier, J.L.; Kensler, T.W.

1990-01-01

Benzoyl peroxide (BzPO), a tumor promoter and progressor in mouse skin, produces strand breaks in DNA of exposed cells. Previously we have reported that the metabolism of BzPO in keratinocytes proceeds via the initial cleavage of the peroxide bond, yielding benzoyloxyl radicals which, in turn, can fragment to form phenyl radicals and carbon dioxide. Benzoic acid, the product of hydrogen abstraction by the benzoyloxyl radical, is the major stable metabolite of BzPO produced by keratinocytes. In the present study we have examined the capacity of BzPO to generate strand scissions in φX-174 plasmid DNA. DNA damage was dose-dependent over a concentration range of 10-1000 μM BzPO and was dependent on the presence of copper but not other transition state metals. By contrast, benzoic acid did not produce DNA damage in this system. The inclusion of spin trapping agents (PBN, DBNBS), radical scavenging agents (Nal, GSH), or the copper chelator o-phenanthroline in incubations was found to significantly reduce the extent of DNA damage. Electron paramagnetic resonance spectroscopy studies suggested that the primary radical trapped was the benzoyloxyl radical, implying a role for this radical in the generation of the observed DNA damage. Collectively these observations suggest BzPO may be activated to DNA damaging intermediates in keratinocytes via metal-catalyzed cleavage of the peroxide bond resulting in the formation of the benzoyloxyl radical. Covalent modification of DNA was not observed when [ 14 C]BzPO was incubated with calf thymus DNA in the presence of copper. Overall, these results suggest that BzPO induces DNA damage via benzoyloxyl radical mediated proton abstraction from the DNA strand and the adduct formation with DNA is unlikely to occur

Influence of combined use of selenious acid and SH compounds in parenteral preparations

Energy Technology Data Exchange (ETDEWEB)

Terada, A. [St. Marianna University School of Medicine, Kawasaki (Japan). Dept. of Public Health]|[St. Marianna University School of Medicine, Kawasaki (Japan). Dept. of Pharmacy; Yoshida, M. [St. Marianna University School of Medicine, Kawasaki (Japan). Dept. of Chemistry; Nakada, M.; Nakada, K.; Yamate, N. [St. Marianna University School of Medicine, Kawasaki (Japan). Dept. of Surgery; Kobayashi, T. [St. Marianna University School of Medicine, Kawasaki (Japan). Dept. of Pharmacy; Yoshida, K. [St. Marianna University School of Medicine, Kawasaki (Japan). Dept. of Public Health

1997-12-31

The influence of the combined use of selenious acid and SH compounds (glutathione (GSH) and cysteine (Cys), or ascorbic acid (Asc)) on cultured venous vascular endothelial cells was investigated experimentally. When cultured human umbilical venous vascular endothelial cells were exposed to 10 {mu}M of selenious acid combined with 0.5 mM-GSH or 0.5 mM-Cys, the release rates of [{sup 3}H]-adenine and lactate dehydrogenase (LDH) from cells into the medium increased significantly as compared with after exposure to selenious acid alone, and damage to the vascular endothelial cells was found to be intensified. Addition of 1 {mu}M of selenious acid simultaneously with 0.5 mM-GSH or 0.5 mM-Cys showed no differences in toxicity for the vascular endothelial cells as compared with the addition of selenious acid alone. On the other hand, simultaneous exposure to 10 {mu}M of selenious acid and 1 mM-Asc induced no significant differences in the release rates of [{sup 3}H]-adenine and LDH, and no damage was observed to the vascular endothelial cells. These results suggest that simultaneous addition of selenious acid together with GSH or Cys, which have the SH-group, may cause damage to the vascular endothelial cells. Therefore careful attention is warranted in total parenteral nutrition. (orig.)

Post-processing of fused silica and its effects on damage resistance to nanosecond pulsed UV lasers.

Science.gov (United States)

Ye, Hui; Li, Yaguo; Zhang, Qinghua; Wang, Wei; Yuan, Zhigang; Wang, Jian; Xu, Qiao

2016-04-10

HF-based (hydrofluoric acid) chemical etching has been a widely accepted technique to improve the laser damage performance of fused silica optics and ensure high-power UV laser systems at designed fluence. Etching processes such as acid concentration, composition, material removal amount, and etching state (etching with additional acoustic power or not) may have a great impact on the laser-induced damage threshold (LIDT) of treated sample surfaces. In order to find out the effects of these factors, we utilized the Taguchi method to determine the etching conditions that are helpful in raising the LIDT. Our results show that the most influential factors are concentration of etchants and the material etched away from the viewpoint of damage performance of fused silica optics. In addition, the additional acoustic power (∼0.6  W·cm-2) may not benefit the etching rate and damage performance of fused silica. Moreover, the post-cleaning procedure of etched samples is also important in damage performances of fused silica optics. Different post-cleaning procedures were, thus, experiments on samples treated under the same etching conditions. It is found that the "spraying + rinsing + spraying" cleaning process is favorable to the removal of etching-induced deposits. Residuals on the etched surface are harmful to surface roughness and optical transmission as well as laser damage performance.

Lipophilic ester and amide derivatives of rosmarinic acid protect cells against H2O2-induced DNA damage and apoptosis: The potential role of intracellular accumulation and labile iron chelation

Directory of Open Access Journals (Sweden)

Paraskevi S. Gerogianni

2018-05-01

Full Text Available Phenolic acids represent abundant components contained in human diet. However, the negative charge in their carboxylic group limits their capacity to diffuse through biological membranes, thus hindering their access to cell interior. In order to promote the diffusion of rosmarinic acid through biological membranes, we synthesized several lipophilic ester- and amide-derivatives of this compound and evaluated their capacity to prevent H2O2-induced DNA damage and apoptosis in cultured human cells. Esterification of the carboxylic moiety with lipophilic groups strongly enhanced the capacity of rosmarinic acid to protect cells. On the other hand, the amide-derivatives were somewhat less effective but exerted less cytotoxicity at high concentrations. Cell uptake experiments, using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS, illustrated different levels of intracellular accumulation among the ester- and amide-derivatives, with the first being more effectively accumulated, probably due to their extensive hydrolysis inside the cells. In conclusion, these results highlight the hitherto unrecognized fundamental importance of derivatization of diet-derived phenolic acids to unveil their biological potential.

Damage analysis: damage function development and application

International Nuclear Information System (INIS)

Simons, R.L.; Odette, G.R.

1975-01-01

The derivation and application of damage functions, including recent developments for the U.S. LMFBR and CTR programs, is reviewed. A primary application of damage functions is in predicting component life expectancies; i.e., the fluence required in a service spectrum to attain a specified design property change. An important part of the analysis is the estimation of the uncertainty in such fluence limit predictions. The status of standardizing the procedures for the derivation and application of damage functions is discussed. Improvements in several areas of damage function development are needed before standardization can be completed. These include increasing the quantity and quality of the data used in the analysis, determining the limitations of the analysis due to the presence of multiple damage mechanisms, and finally, testing of damage function predictions against data obtained from material surveillance programs in operating thermal and fast reactors. 23 references. (auth)

Inactivation of thiol-dependent enzymes by hypothiocyanous acid: role of sulfenyl thiocyanate and sulfenic acid intermediates

Science.gov (United States)

Barrett, Tessa J.; Pattison, David I.; Leonard, Stephen E.; Carroll, Kate S.; Davies, Michael J.; Hawkins, Clare L.

2012-01-01

Myeloperoxidase (MPO) forms reactive oxidants including hypochlorous and hypothiocyanous acids (HOCl and HOSCN) under inflammatory conditions. HOCl causes extensive tissue damage and plays a role in the progression of many inflammatory-based diseases. Although HOSCN is a major MPO oxidant, particularly in smokers, who have elevated plasma thiocyanate, the role of this oxidant in disease is poorly characterized. HOSCN induces cellular damage by targeting thiols. However, the specific targets and mechanisms involved in this process are not well defined. We show that exposure of macrophages to HOSCN results in the inactivation of intracellular enzymes, including creatine kinase (CK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In each case, the active-site thiol residue is particularly sensitive to oxidation, with evidence for reversible inactivation and the formation of sulfenyl thiocyanate and sulfenic acid intermediates, on treatment with HOSCN (less than fivefold molar excess). Experiments with DAz-2, a cell-permeable chemical trap for sulfenic acids, demonstrate that these intermediates are formed on many cellular proteins, including GAPDH and CK, in macrophages exposed to HOSCN. This is the first direct evidence for the formation of protein sulfenic acids in HOSCN-treated cells and highlights the potential of this oxidant to perturb redox signaling processes. PMID:22248862

Enterococcus faecalis Responds to Individual Exogenous Fatty Acids Independently of Their Degree of Saturation or Chain Length.

Science.gov (United States)

Saito, Holly E; Harp, John R; Fozo, Elizabeth M

2018-01-01

Enterococcus faecalis is a commensal of the human gastrointestinal tract that can persist in the external environment and is a leading cause of hospital-acquired infections. Given its diverse habitats, the organism has developed numerous strategies to survive a multitude of environmental conditions. Previous studies have demonstrated that E. faecalis will incorporate fatty acids from bile and serum into its membrane, resulting in an induced tolerance to membrane-damaging agents. To discern whether all fatty acids induce membrane stress protection, we examined how E. faecalis responded to individually supplied fatty acids. E. faecalis readily incorporated fatty acids 14 to 18 carbons in length into its membrane but poorly incorporated fatty acids shorter or longer than this length. Supplementation with saturated fatty acids tended to increase generation time and lead to altered cellular morphology in most cases. Further, exogenously supplied saturated fatty acids did not induce tolerance to the membrane-damaging antibiotic daptomycin. Supplementation with unsaturated fatty acids produced variable growth effects, with some impacting generation time and morphology. Exogenously supplied unsaturated fatty acids that are normally produced by E. faecalis and those that are found in bile or serum could restore growth in the presence of a fatty acid biosynthetic inhibitor. However, only the eukaryote-derived fatty acids oleic acid and linoleic acid provided protection from daptomycin. Thus, exogenous fatty acids do not lead to a common physiological effect on E. faecalis The organism responds uniquely to each, and only host-derived fatty acids induce membrane protection. IMPORTANCE Enterococcus faecalis is a commonly acquired hospital infectious agent with resistance to many antibiotics, including those that target its cellular membrane. We previously demonstrated that E. faecalis will incorporate fatty acids found in human fluids, like serum, into its cellular membrane

Lipids and Oxidative Stress Associated with Ethanol-Induced Neurological Damage

Directory of Open Access Journals (Sweden)

José A. Hernández

2016-01-01

Full Text Available The excessive intake of alcohol is a serious public health problem, especially given the severe damage provoked by chronic or prenatal exposure to alcohol that affects many physiological processes, such as memory, motor function, and cognitive abilities. This damage is related to the ethanol oxidation in the brain. The metabolism of ethanol to acetaldehyde and then to acetate is associated with the production of reactive oxygen species that accentuate the oxidative state of cells. This metabolism of ethanol can induce the oxidation of the fatty acids in phospholipids, and the bioactive aldehydes produced are known to be associated with neurotoxicity and neurodegeneration. As such, here we will review the role of lipids in the neuronal damage induced by ethanol-related oxidative stress and the role that lipids play in the related compensatory or defense mechanisms.

Exogenous 5-aminolevulenic acid promotes seed germination in Elymus nutans against oxidative damage induced by cold stress.

Directory of Open Access Journals (Sweden)

Juanjuan Fu

Full Text Available The protective effects of 5-aminolevulenic acid (ALA on germination of Elymus nutans Griseb. seeds under cold stress were investigated. Seeds of E. nutans (Damxung, DX and Zhengdao, ZD were pre-soaked with various concentrations (0, 0.1, 0.5, 1, 5, 10 and 25 mg l(-1 of ALA for 24 h before germination under cold stress (5°C. Seeds of ZD were more susceptible to cold stress than DX seeds. Both seeds treated with ALA at low concentrations (0.1-1 mg l(-1 had higher final germination percentage (FGP and dry weight at 5°C than non-ALA-treated seeds, whereas exposure to higher ALA concentrations (5-25 mg l(-1 brought about a dose dependent decrease. The highest FGP and dry weight of germinating seeds were obtained from seeds pre-soaked with 1 mg l(-1 ALA. After 5 d of cold stress, pretreatment with ALA provided significant protection against cold stress in the germinating seeds, significantly enhancing seed respiration rate and ATP synthesis. ALA pre-treatment also increased reduced glutathione (GSH, ascorbic acid (AsA, total glutathione, and total ascorbate concentrations, and the activities of superoxide dismutase (SOD, catalase (CAT, ascorbate peroxidase (APX and glutathione reductase (GR, whereas decreased the contents of malondialdehyde (MDA and hydrogen peroxide (H2O2, and superoxide radical (O2•- release in both germinating seeds under cold stress. In addition, application of ALA increased H+-ATPase activity and endogenous ALA concentration compared with cold stress alone. Results indicate that ALA considered as an endogenous plant growth regulator could effectively protect E. nutans seeds from cold-induced oxidative damage during germination without any adverse effect.

Modeling DNA

Science.gov (United States)

Robertson, Carol

2016-01-01

Deoxyribonucleic acid (DNA) is life's most amazing molecule. It carries the genetic instructions that almost every organism needs to develop and reproduce. In the human genome alone, there are some three billion DNA base pairs. The most difficult part of teaching DNA structure, however, may be getting students to visualize something as small as a…

Public Perceptions and Expectations of the Forensic Use of DNA: Results of a Preliminary Study

Science.gov (United States)

Curtis, Cate

2009-01-01

The forensic use of Deoxyribonucleic Acid (DNA) is demonstrating significant success as a crime-solving tool. However, numerous concerns have been raised regarding the potential for DNA use to contravene cultural, ethical, and legal codes. In this article the expectations and level of knowledge of the New Zealand public of the DNA data-bank and…

Omega-3 fatty acids alter behavioral and oxidative stress parameters in animals subjected to fenproporex administration.

Science.gov (United States)

Model, Camila S; Gomes, Lara M; Scaini, Giselli; Ferreira, Gabriela K; Gonçalves, Cinara L; Rezin, Gislaine T; Steckert, Amanda V; Valvassori, Samira S; Varela, Roger B; Quevedo, João; Streck, Emilio L

2014-03-01

Studies have consistently reported the participation of oxidative stress in bipolar disorder (BD). Evidences indicate that omega-3 (ω3) fatty acids play several important roles in brain development and functioning. Moreover, preclinical and clinical evidence suggests roles for ω3 fatty acids in BD. Considering these evidences, the present study aimed to investigate the effects of ω3 fatty acids on locomotor behavior and oxidative stress parameters (TBARS and protein carbonyl content) in brain of rats subjected to an animal model of mania induced by fenproporex. The fenproporex treatment increased locomotor behavior in saline-treated rats under reversion and prevention model, and ω3 fatty acids prevented fenproporex-related hyperactivity. Moreover, fenproporex increased protein carbonyls in the prefrontal cortex and cerebral cortex, and the administration of ω3 fatty acids reversed this effect. Lipid peroxidation products also are increased in prefrontal cortex, striatum, hippocampus and cerebral after fenproporex administration, but ω3 fatty acids reversed this damage only in the hippocampus. On the other hand, in the prevention model, fenproporex increased carbonyl content only in the cerebral cortex, and administration of ω3 fatty acids prevented this damage. Additionally, the administration of fenproporex resulted in a marked increased of TBARS in the prefrontal cortex, hippocampus, striatum and cerebral cortex, and prevent this damage in the prefrontal cortex, hippocampus and striatum. In conclusion, we are able to demonstrate that fenproporex-induced hyperlocomotion and damage through oxidative stress were prevented by ω3 fatty acids. Thus, the ω3 fatty acids may be important adjuvant therapy of bipolar disorder.

Characterization of deoxyribonucleic acid from cells infected with Aleutian disease virus

International Nuclear Information System (INIS)

Hahn, E.C.; Ramos, L.; Kenyon, A.J.

1983-01-01

Viral DNA was extracted from Crandell feline kidney (CRFK) cells infected with Aleutian disease virus (ADV) and labeled with [ 3 H]thymidine. The sedimentation coefficient in alkaline sucrose gradients was 16S corresponding to a molecular weight of 1.5 X 10(6). The buoyant densities of DNA from infected and control cells were determined by isopyknic sedimentation in CsCl and NaI gradients. Two additional peaks of [ 3 H]DNA were found in infected cells, but not in control cell extracts. Fractionation of this DNA on hydroxylapatite indicated that the new peaks represented a single-stranded component, density 1.728 g/cm3, and a double-stranded component, presumed to be a viral replicative intermediate, density 1.718 g/cm3. The target antigen formation in CRFK cells was measured by gamma-irradiation of ADV and assayed for focus formation. The calculated size of ADV based on these measurements was 1.1 X 10(6). The H-1 parvovirus also was shown to have a size of 1.5 X 10(6) daltons for both antigen and plaque formation. The data indicated similarities existed between ADV and other autonomously replicating parvoviruses in most properties, except that less-than-unit length genome of ADV may be transcribed

Spermine induced reversible collapse of deoxyribonucleic acid-bridged nanoparticle-based assemblies

NARCIS (Netherlands)

Göeken, Kristian L.; Schasfoort, Richardus B.M.; Subramaniam, Vinod; Gill, Ron

DNA-linked 2D and 3D nano-assemblies find use in a diverse set of applications, ranging from DNA-origami in drug delivery and medical imaging, to DNA-linked nanoparticle structures for use in plasmonics and (bio)sensing. However, once these structures have been fully assembled, few options are

R Factor-Controlled Restriction and Modification of Deoxyribonucleic Acid: Restriction Mutants

Science.gov (United States)

Yoshimori, Robert; Roulland-Dussoix, Daisy; Boyer, Herbert W.

1972-01-01

Restriction mutants of two different R factor-controlled host specificities (RI and RII) were isolated. All of the restriction mutants examined had a normal modification phenotype. No complementation was observed between the RI and RII host specificities. It is concluded that for each host specificity no protein subunit is shared by the restriction endonuclease and modification methylase. PMID:4565538

Voltammetric Detection of Damage to DNA by Arsenic Compounds at a DNA Biosensor

Directory of Open Access Journals (Sweden)

R. Wennrich

2005-11-01

Full Text Available DNA biosensor can serve as a powerfull tool for simple in vitro tests of chemicaltoxicity. In this paper, damage to DNA attached to the surface of screen-printed carbonelectrode by arsenic compounds in solution is described. Using the Co(III complex with1,10-phenanthroline, [Co(phen3]3+ , as an electrochemical DNA marker and the Ru(IIcomplex with bipyridyne, [Ru(bipy3]2+ , as a DNA oxidation catalyst, the portion of originaldsDNA which survives an incubation of the biosensor in the cleavage medium was evaluated.The model cleavage mixture was composed of an arsenic compound at 10-3 mol/Lconcentration corresponding to real contaminated water, 2x10-4 mol/L Fe(II or Cu(II ions asthe redox catalyst, and 1.5x10-2 mol/L hydrogen peroxide. DNA damage by arsenite,dimethylarsinic acid as the metabolic product of inorganic arsenic and widely used herbicide,as well as phenylarsonic acid and p-arsanilic acid as the representatives of feed additives wasfound in difference to arsenate.

Damage of crops by environmental air pollution in Yokkaichi area

Energy Technology Data Exchange (ETDEWEB)

Taniyama, T; Sawanaka, K

1972-01-01

Crop damage from sulfur dioxide was evaluated in the Yokkaichi area in 1971 by measuring dry matter and seed production. The average concentration of SO/sub 2/ per hour was 0.034 ppM from April to November 1971. There were, however, some cases of monthly hourly averages greater than 0.4 ppM. In these situations damages to major crops was largely due to sulfurous and sulfuric acid mists. The damages to major crops included brown and red spots, apical and peripheral chlorosis, yellowing of leaves, belt-like yellowing of sheath, white or black discoloration of rice plants, nonfertilization of rice plants, apical blight and chlorosis of Welsh onion, partial yellowing and general withering of pine trees in summer (and some death), watering and chlorosis of leaves of brassica species, and yellowing and spot formation on Japanese radishes. Also noted was a decrease in tiller number of rice plants (17.4 in polluted vs. 19.4 in unpolluted areas). Some cases were found in which the sulfur content of SO/sub 2/-damaged crops was higher than that of undamaged crops.

The current state of eukaryotic DNA base damage and repair.

Science.gov (United States)

Bauer, Nicholas C; Corbett, Anita H; Doetsch, Paul W

2015-12-02

DNA damage is a natural hazard of life. The most common DNA lesions are base, sugar, and single-strand break damage resulting from oxidation, alkylation, deamination, and spontaneous hydrolysis. If left unrepaired, such lesions can become fixed in the genome as permanent mutations. Thus, evolution has led to the creation of several highly conserved, partially redundant pathways to repair or mitigate the effects of DNA base damage. The biochemical mechanisms of these pathways have been well characterized and the impact of this work was recently highlighted by the selection of Tomas Lindahl, Aziz Sancar and Paul Modrich as the recipients of the 2015 Nobel Prize in Chemistry for their seminal work in defining DNA repair pathways. However, how these repair pathways are regulated and interconnected is still being elucidated. This review focuses on the classical base excision repair and strand incision pathways in eukaryotes, considering both Saccharomyces cerevisiae and humans, and extends to some important questions and challenges facing the field of DNA base damage repair. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Gum acacia mitigates genetic damage in adenine-induced chronic renal failure in rats.

Science.gov (United States)

Ali, B H; Al Balushi, K; Al-Husseini, I; Mandel, P; Nemmar, A; Schupp, N; Ribeiro, D A

2015-12-01

Subjects with chronic renal failure (CRF) exhibit oxidative genome damage, which may predispose to carcinogenesis, and Gum acacia (GumA) ameliorates this condition in humans and animals. We evaluated here renal DNA damage and urinary excretion of four nucleic acid oxidation adducts namely 8-oxoguanine (8-oxoGua), 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), 8-oxoguanosine (8-oxoGuo) and 8-hydroxy-2-deoxyguanisone (8-OHdg) in rats with adenine (ADE)-induced CRF with and without GumA treatment. Twenty-four rats were divided into four equal groups and treated for 4 weeks. The first group was given normal food and water (control). The second group was given normal food and GumA (15% w/v) in drinking water. The third group was fed powder diet containing adenine (ADE) (0·75% w/w in feed). The fourth group was fed like in the third group, plus GumA in drinking water (15%, w/v). ADE feeding induced CRF (as measured by several physiological, biochemical and histological indices) and also caused a significant genetic damage and significant decreases in urinary 8-oxo Gua and 8-oxoGuo, but not in the other nucleic acids. However, concomitant GumA treatment reduced the level of genetic damage in kidney cells as detected by Comet assay and significantly reversed the effect of adenine on urinary 8-oxoGuo. Treatment with GumA is able to mitigate genetic damage in renal tissues of rats with ADE-induced CRF. © 2015 Stichting European Society for Clinical Investigation Journal Foundation.

Arabidopsis and Maize RidA Proteins Preempt Reactive Enamine/Imine Damage to Branched-Chain Amino Acid Biosynthesis in Plastids[C][W][OPEN

Science.gov (United States)

Niehaus, Thomas D.; Nguyen, Thuy N.D.; Gidda, Satinder K.; ElBadawi-Sidhu, Mona; Lambrecht, Jennifer A.; McCarty, Donald R.; Downs, Diana M.; Cooper, Arthur J.L.; Fiehn, Oliver; Mullen, Robert T.; Hanson, Andrew D.

2014-01-01

RidA (for Reactive Intermediate Deaminase A) proteins are ubiquitous, yet their function in eukaryotes is unclear. It is known that deleting Salmonella enterica ridA causes Ser sensitivity and that S. enterica RidA and its homologs from other organisms hydrolyze the enamine/imine intermediates that Thr dehydratase forms from Ser or Thr. In S. enterica, the Ser-derived enamine/imine inactivates a branched-chain aminotransferase; RidA prevents this damage. Arabidopsis thaliana and maize (Zea mays) have a RidA homolog that is predicted to be plastidial. Expression of either homolog complemented the Ser sensitivity of the S. enterica ridA mutant. The purified proteins hydrolyzed the enamines/imines formed by Thr dehydratase from Ser or Thr and protected the Arabidopsis plastidial branched-chain aminotransferase BCAT3 from inactivation by the Ser-derived enamine/imine. In vitro chloroplast import assays and in vivo localization of green fluorescent protein fusions showed that Arabidopsis RidA and Thr dehydratase are chloroplast targeted. Disrupting Arabidopsis RidA reduced root growth and raised the root and shoot levels of the branched-chain amino acid biosynthesis intermediate 2-oxobutanoate; Ser treatment exacerbated these effects in roots. Supplying Ile reversed the root growth defect. These results indicate that plastidial RidA proteins can preempt damage to BCAT3 and Ile biosynthesis by hydrolyzing the Ser-derived enamine/imine product of Thr dehydratase. PMID:25070638

Boric acid reduces axonal and myelin damage in experimental sciatic nerve injury

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Zahir Kizilay

2016-01-01

Full Text Available The aim of this study was to investigate the effects of boric acid in experimental acute sciatic nerve injury. Twenty-eight adult male rats were randomly divided into four equal groups (n = 7: control (C, boric acid (BA, sciatic nerve injury (I , and sciatic nerve injury + boric acid treatment (BAI. Sciatic nerve injury was generated using a Yasargil aneurysm clip in the groups I and BAI. Boric acid was given four times at 100 mg/kg to rats in the groups BA and BAI after injury (by gavage at 0, 24, 48 and 72 hours but no injury was made in the group BA. In vivo electrophysiological tests were performed at the end of the day 4 and sciatic nerve tissue samples were taken for histopathological examination. The amplitude of compound action potential, the nerve conduction velocity and the number of axons were significantly lower and the myelin structure was found to be broken in group I compared with those in groups C and BA. However, the amplitude of the compound action potential, the nerve conduction velocity and the number of axons were significantly greater in group BAI than in group I. Moreover, myelin injury was significantly milder and the intensity of nuclear factor kappa B immunostaining was significantly weaker in group BAI than in group I. The results of this study show that administration of boric acid at 100 mg/kg after sciatic nerve injury in rats markedly reduces myelin and axonal injury and improves the electrophysiological function of injured sciatic nerve possibly through alleviating oxidative stress reactions.

Clustered DNA damage induced by proton and heavy ion irradiation

International Nuclear Information System (INIS)

Davidkova, M.; Pachnerova Brabcova, K; Stepan, V.; Vysin, L.; Sihver, L.; Incerti, S.

2014-01-01

Ionizing radiation induces in DNA strand breaks, damaged bases and modified sugars, which accumulate with increasing density of ionizations in charged particle tracks. Compared to isolated DNA damage sites, the biological toxicity of damage clusters can be for living cells more severe. We investigated the clustered DNA damage induced by protons (30 MeV) and high LET radiation (C 290 MeV/u and Fe 500 MeV/u) in pBR322 plasmid DNA. To distinguish between direct and indirect pathways of radiation damage, the plasmid was irradiated in pure water or in aqueous solution of one of the three scavengers (coumarin-3-carboxylic acid, dimethylsulfoxide, and glycylglycine). The goal of the contribution is the analysis of determined types of DNA damage in dependence on radiation quality and related contribution of direct and indirect radiation effects. The yield of double strand breaks (DSB) induced in the DNA plasmid-scavenger system by heavy ion radiation was found to decrease with increasing scavenging capacity due to reaction with hydroxyl radical, linearly with high correlation coefficients. The yield of non-DSB clusters was found to occur twice as much as the DSB. Their decrease with increasing scavenging capacity had lower linear correlation coefficients. This indicates that the yield of non-DSB clusters depends on more factors, which are likely connected to the chemical properties of individual scavengers. (authors)

Intracerebroventricular Kainic Acid-Induced Damage Affects Blood Glucose Level in d-glucose-fed Mouse Model.

Science.gov (United States)

Kim, Chea-Ha; Hong, Jae-Seung

2015-03-01

We have previously reported that the intracerebroventricular (i.c.v.) administration of kainic acid (KA) results in significant neuronal damage on the hippocampal CA3 region. In this study, we examined possible changes in the blood glucose level after i.c.v. pretreatment with KA. The blood glucose level was elevated at 30 min, began to decrease at 60 min and returned to normal at 120 min after D-glucose-feeding. We found that the blood glucose level in the KA-pretreated group was higher than in the saline-pretreated group. The up-regulation of the blood glucose level in the KA-pretreated group was still present even after 1~4 weeks. The plasma corticosterone and insulin levels were slightly higher in the KA-treated group. Corticosterone levels decreased whereas insulin levels were elevated when mice were fed with D-glucose. The i.c.v. pretreatment with KA for 24 hr caused a significant reversal of D-glucose-induced down-regulation of corticosterone level. However, the insulin level was enhanced in the KA-pretreated group compared to the vehicle-treated group when mice were fed with D-glucose. These results suggest that KA-induced alterations of the blood glucose level are related to cell death in the CA3 region whereas the up-regulation of blood glucose level in the KA-pretreated group appears to be due to a reversal of D-glucose feeding-induced down-regulation of corticosterone level.

cDNA, genomic sequence cloning and analysis of the ribosomal ...

African Journals Online (AJOL)

Ribosomal protein L37A (RPL37A) is a component of 60S large ribosomal subunit encoded by the RPL37A gene, which belongs to the family of ribosomal L37AE proteins, located in the cytoplasm. The complementary deoxyribonucleic acid (cDNA) and the genomic sequence of RPL37A were cloned successfully from giant ...

Engineering artificial machines from designable DNA materials for biomedical applications.

Science.gov (United States)

Qi, Hao; Huang, Guoyou; Han, Yulong; Zhang, Xiaohui; Li, Yuhui; Pingguan-Murphy, Belinda; Lu, Tian Jian; Xu, Feng; Wang, Lin

2015-06-01

Deoxyribonucleic acid (DNA) emerges as building bricks for the fabrication of nanostructure with complete artificial architecture and geometry. The amazing ability of DNA in building two- and three-dimensional structures raises the possibility of developing smart nanomachines with versatile controllability for various applications. Here, we overviewed the recent progresses in engineering DNA machines for specific bioengineering and biomedical applications.

Biotechnology

International Nuclear Information System (INIS)

Lewanika, Mbikusita Mwananyanda

2005-01-01

The article sets out to explain in simple terms the main concepts of Biotechnology beginning with traditional biotechnology to modern biotechnology. It outlines fundamentals of Recombinant Deoxyribonucleic Acid (DNA), Genetically Modified Organisms (GMOs) and Genetic Engineering. The article offers a discussion of the benefits, disadvantages and the general public and policy concerns regarding genetically modified organisms

A New Multichelating Acid System for High-Temperature Sandstone Reservoirs

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Nianyin Li

2015-01-01

Full Text Available Sandstone reservoir acidizing is a complex and heterogeneous acid-rock reaction process. If improper acid treatment is implemented, further damage can be induced instead of removing the initial plug, particularly in high-temperature sandstone reservoirs. An efficient acid system is the key to successful acid treatment. High-temperature sandstone treatment with conventional mud acid system faces problems including high acid-rock reaction rate, short acid effective distance, susceptibility to secondary damage, and serious corrosion to pipelines. In this paper, a new multichelating acid system has been developed to overcome these shortcomings. The acid system is composed of ternary weak acid, organic phosphonic chelating agent, anionic polycarboxylic acid chelating dispersant, fluoride, and other assisted additives. Hydrogen ion slowly released by multistage ionization in ternary weak acid and organic phosphonic within the system decreases the concentration of HF to achieve retardation. Chelating agent and chelating dispersant within the system inhibited anodic and cathodic reaction, respectively, to protect the metal from corrosion, while chelating dispersant has great chelating ability on iron ions, restricting the depolarization reaction of ferric ion and metal. The synergic effect of chelating agent and chelating dispersant removes sulfate scale precipitation and inhibits or decreases potential precipitation such as CaF2, silica gel, and fluosilicate. Mechanisms of retardation, corrosion-inhibition, and scale-removing features have been discussed and evaluated with laboratory tests. Test results indicate that this novel acid system has good overall performance, addressing the technical problems and improving the acidizing effect as well for high-temperature sandstone.

Hormesis in Cholestatic Liver Disease; Preconditioning with Low Bile Acid Concentrations Protects against Bile Acid-Induced Toxicity.

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Esther M Verhaag

Full Text Available Cholestasis is characterized by accumulation of bile acids and inflammation, causing hepatocellular damage. Still, liver damage markers are highest in acute cholestasis and drop when this condition becomes chronic, indicating that hepatocytes adapt towards the hostile environment. This may be explained by a hormetic response in hepatocytes that limits cell death during cholestasis.To investigate the mechanisms that underlie the hormetic response that protect hepatocytes against experimental cholestatic conditions.HepG2.rNtcp cells were preconditioned (24 h with sub-apoptotic concentrations (0.1-50 μM of various bile acids, the superoxide donor menadione, TNF-α or the Farsenoid X Receptor agonist GW4064, followed by a challenge with the apoptosis-inducing bile acid glycochenodeoxycholic acid (GCDCA; 200 μM for 4 h, menadione (50 μM, 6 h or cytokine mixture (CM; 6 h. Levels of apoptotic and necrotic cell death, mRNA expression of the bile salt export pump (ABCB11 and bile acid sensors, as well as intracellular GCDCA levels were analyzed.Preconditioning with the pro-apoptotic bile acids GCDCA, taurocholic acid, or the protective bile acids (tauroursodeoxycholic acid reduced GCDCA-induced caspase-3/7 activity in HepG2.rNtcp cells. Bile acid preconditioning did not induce significant levels of necrosis in GCDCA-challenged HepG2.rNtcp cells. In contrast, preconditioning with cholic acid, menadione or TNF-α potentiated GCDCA-induced apoptosis. GCDCA preconditioning specifically reduced GCDCA-induced cell death and not CM- or menadione-induced apoptosis. The hormetic effect of GCDCA preconditioning was concentration- and time-dependent. GCDCA-, CDCA- and GW4064- preconditioning enhanced ABCB11 mRNA levels, but in contrast to the bile acids, GW4064 did not significantly reduce GCDCA-induced caspase-3/7 activity. The GCDCA challenge strongly increased intracellular levels of this bile acid, which was not lowered by GCDCA

Animal model of acid-reflux esophagitis: pathogenic roles of acid/pepsin, prostaglandins, and amino acids.

Science.gov (United States)

Takeuchi, Koji; Nagahama, Kenji

2014-01-01

Esophagitis was induced in rats within 3 h by ligating both the pylorus and transitional region between the forestomach and glandular portion under ether anesthesia. This esophageal injury was prevented by the administration of acid suppressants and antipepsin drug and aggravated by exogenous pepsin. Damage was also aggravated by pretreatment with indomethacin and the selective COX-1 but not COX-2 inhibitor, whereas PGE2 showed a biphasic effect depending on the dose; a protection at low doses, and an aggravation at high doses, with both being mediated by EP1 receptors. Various amino acids also affected this esophagitis in different ways; L-alanine and L-glutamine had a deleterious effect, while L-arginine and glycine were highly protective, both due to yet unidentified mechanisms. It is assumed that acid/pepsin plays a major pathogenic role in this model of esophagitis; PGs derived from COX-1 are involved in mucosal defense of the esophagus; and some amino acids are protective against esophagitis. These findings also suggest a novel therapeutic approach in the treatment of esophagitis, in addition to acid suppressant therapy. The model introduced may be useful to test the protective effects of drugs on esophagitis and investigate the mucosal defense mechanism in the esophagus.

Induction of DNA damage by oxidised amino acids and proteins

DEFF Research Database (Denmark)

Luxford, Catherine; Dean, Roger T; Davies, Michael Jonathan

2002-01-01

Exposure of amino acids, peptides and proteins to radicals in the presence of O2 generates hydroperoxides in a dose-dependent manner. These hydroperoxides are stable in the absence of exogenous catalysts (e.g. heat, light, redox-active transition metal ions), but decompose rapidly in the presence...

The dilemma of an acidic sky

International Nuclear Information System (INIS)

Jenkins, T.

1984-01-01

A discussion of studies detailing the damaging effects of acid precipitation in North America and Europe is followed by a commentary on the controversial political and economic issues associated with forestalling deterioration of the environment. A comprehensive bibliography is included

ESR study of radiation damage in pyrimidines. Progress report, August 1, 1975--April 1, 1976

International Nuclear Information System (INIS)

Benson, B.W.

1976-04-01

The primary objective of this project is to develop general mechanisms for radiation damage to biomolecules using substituted pyrimidines as a model system. Results this year include a single crystal ESR study of 5-ethyl-5-isopropylbarbituric acid, development of the k-band microwave bridge, dose response measurements on methylated barbituric acid derivatives, and synthesis of several specifically deuterated uracil derivatives

Carnitine prevents the early mitochondrial damage induced by methylglyoxal bis(guanylhydrazone) in L1210 leukaemia cells.

Science.gov (United States)

Nikula, P; Ruohola, H; Alhonen-Hongisto, L; Jänne, J

1985-06-01

We previously found that the anti-cancer drug methylglyoxal bis(guanylhydrazone) (mitoguazone) depresses carnitine-dependent oxidation of long-chain fatty acids in cultured mouse leukaemia cells [Nikula, Alhonen-Hongisto, Seppänen & Jänne (1984) Biochem. Biophys. Res. Commun. 120, 9-14]. We have now investigated whether carnitine also influences the development of the well-known mitochondrial damage produced by the drug in L1210 leukaemia cells. Palmitate oxidation was distinctly inhibited in tumour cells exposed to 5 microM-methylglyoxal bis(guanylhydrazone) for only 7 h. Electron-microscopic examination of the drug-exposed cells revealed that more than half of the mitochondria were severely damaged. Similar exposure of the leukaemia cells to the drug in the presence of carnitine not only abolished the inhibition of fatty acid oxidation but almost completely prevented the drug-induced mitochondrial damage. The protection provided by carnitine appeared to depend on the intracellular concentration of methylglyoxal bis(guanylhydrazone), since the mitochondria-sparing effect disappeared at higher drug concentrations.

Does the phycotoxin Okadaic acid cause oxidative stress damages and histological alterations to seabream (Sparus aurata)?

Science.gov (United States)

Souid, Ghada; Souayed, Nouha; Haouas, Zohra; Maaroufi, Khira

2018-03-15

Okadaic Acid (OA) is a marine toxin responsible for DSP (Diarrheic Shellfish Poisoning) in humans produced by dinoflagellate. The genotoxic and cytotoxic effects of OA have been well reported in mammalian experimental animals and in vitro cultured cells. However, there are no available investigations regarding the involvement of the oxidative stress pathways in OA toxicity, especially on aquatic animals such as fish. In this context, we aimed in the present work to demonstrate whether OA (7.5 μg/ml) induces oxidative stress and histopathological damages in the fish species Sparus aurata under short term exposure (2 h, 4 h and 24 h). To this end, we have assessed lipid peroxidation and anti-oxidative stress response in liver tissue, and finally ultrastructural changes were investigated in hepatic and gills tissues. Our results clearly showed that OA induced significant enhancement in all tested parameters in a time dependent manner and seems to be a strong inducer of oxidative stress in aquatic animals. The data of the present study indicate also that histology is a successful tool to reveal OA impact on liver and gill tissues of Sparus aurata since the animal showed vascular dilation and hepatocellular membrane disintegration in liver and hypertrophy in secondary lamellae and necrotic aspect in the primary lamellae in gill tissue. Copyright © 2018 Elsevier Ltd. All rights reserved.

Damage detection in high-rise buildings using damage-induced rotations

International Nuclear Information System (INIS)

Sung, Seung Hun; Jung, Ho Youn; Lee, Jung Hoon; Jung, Hyung Jo

2016-01-01

In this paper, a new damage-detection method based on structural vibration is proposed. The essence of the proposed method is the detection of abrupt changes in rotation. Damage-induced rotation (DIR), which is determined from the modal flexibility of the structure, initially occurs only at a specific damaged location. Therefore, damage can be localized by evaluating abrupt changes in rotation. We conducted numerical simulations of two damage scenarios using a 10-story cantilever-type building model. Measurement noise was also considered in the simulation. We compared the sensitivity of the proposed method to localize damage to that of two conventional modal-flexibility-based damage-detection methods, i.e., uniform load surface (ULS) and ULS curvature. The proposed method was able to localize damage in both damage scenarios for cantilever structures, but the conventional methods could not

Damage detection in high-rise buildings using damage-induced rotations

International Nuclear Information System (INIS)

Sung, Seung Hoon; Jung, Ho Youn; Lee, Jung Hoon; Jung, Hyung Jo

2014-01-01

In this paper, a new damage-detection method based on structural vibration is proposed. The essence of the proposed method is the detection of abrupt changes in rotation. Damage-induced rotation (DIR), which is determined from the modal flexibility of the structure, initially occurs only at a specific damaged location. Therefore, damage can be localized by evaluating abrupt changes in rotation. We conducted numerical simulations of two damage scenarios using a 10-story cantilever-type building model. Measurement noise was also considered in the simulation. We compared the sensitivity of the proposed method to localize damage to that of two conventional modal-flexibility-based damage-detection methods, i.e., uniform load surface (ULS) and ULS curvature. The proposed method was able to localize damage in both damage scenarios for cantilever structures, but the conventional methods could not.

Measurement of damage in systemic vasculitis: a comparison of the Vasculitis Damage Index with the Combined Damage Assessment Index

DEFF Research Database (Denmark)

Suppiah, Ravi; Flossman, Oliver; Mukhtyar, Chetan

2011-01-01

To compare the Vasculitis Damage Index (VDI) with the Combined Damage Assessment Index (CDA) as measures of damage from vasculitis.......To compare the Vasculitis Damage Index (VDI) with the Combined Damage Assessment Index (CDA) as measures of damage from vasculitis....

Atgl gene deletion predisposes to proximal tubule damage by impairing the fatty acid metabolism

International Nuclear Information System (INIS)

Chen, Wen; Zhang, Qiong; Cheng, Shiwu; Huang, Jie; Diao, Ge; Han, Jian

2017-01-01

Fibrosis is the final common pathway of chronic kidney disease (CKD). Normal lipid metabolism is integral to renal physiology, and disturbances of renal lipid metabolism are increasingly being linked with CKD, including the fibrosis. Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme of lipolysis. In the present study, we used Atgl −/− mice to investigate whether ATGL played a role in the regulation of proximal convoluted tubule (PCT) lipid metabolism and renal fibrosis development. ATGL deficiency led to lipid vacuolation of PCT and tubulointerstitial fibrosis, accompanied by massive albuminuria and decreased creatinine clearance rate (Ccr). In vitro experiments indicated that inhibition of ATGL in proximal tubular cell line HK-2 promoted intracellular lipid deposition, reactive oxygen species (ROS) accumulation and cell apoptosis. Both in vitro and in vivo experiments showed that ATGL inhibition decreased the renal peroxisome proliferator-activated receptorα(PPARα) expression, which implied the suppressed lipid metabolism. The antioxidant N-acetylcysteine (NAC) could partially reverse the effect of ROS accumulation and cell apoptosis, but could not restore the PPARαdecrease. These data raise the possibility that ATGL deficiency could impair the renal fatty acid metabolism though inhibiting PPARαexpression, which may lead to lipid deposition and cell apoptosis of PCT, and finally contribute to the renal fibrosis and dysfunction. - Highlights: • Atgl −/− mice develop tubulointerstitial damage and renal dysfunction. • ATGL deficiency results in lipid accumulation and apoptosis of proximal tubular cells. • ROS scavenger alleviates the ATGL-knockdown mediated lipid accumulation and apoptosis. • PPARαdown-regulation is the reason of ROS elevating in ATGL-knockdown HK-2 cells.

The Effects of Adding Whey Protein and Branched-chain Amino Acid to Carbohydrate Beverages on Indices of Muscle Damage after Eccentric Resistance Exercise in Untrained Young Males

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Foad Asjodi

2017-07-01

Full Text Available Abstract Background: The aim of this study was to evaluate the effects of supplementation of Branched-Chain Amino Acids (BCAAs plus carbohydrate (CHO and whey protein plus CHO on muscle damage indices after eccentric resistant exercise. Materials and Methods: Twenty four untrained healthy males participated in this study. They were randomly divided into three groups, BCAA +glucose (0.1+0.1g/kg supplement group (n=8, Whey+glucose (0.1+0.1g/kg supplement group (n=8, and placebo (malto dextrin 0.2g/kg group (n=8. Each subject consumed a carbohydrate beverage with addition of whey protein or branched-chain amino acid or placebo 30 minutes before exercise in a randomized,double-blind fashion. Serum levels of Creatine Kinase (CK, Lactate dehydrogenase (LDH, and muscle pain were measured before, 24, 48, 72 h after exercise. Follow-up analyses included 1-way repeated measures ANOVAs, and Bonferroni post hoc comparisons. Results: 24 h after test, serum levels of CK, LDH and muscle pain in both supplement groups were increased less than placebo group (0.015, 0.001 and 0.001, respectively. Also, the levels of CK and LDH showed significant changes in both intervention groups compared to placebo group at 24 h (0.001, 0. 015, respectively. Similarly, significant differences in the levels of CK and LDH between groups were observed. Conclusion: These data indicate that muscle damage and pain after resistant exercise were reduced by an ingestion of either BCAA drink or whey protein drink.

Protein carbonyl content: a novel biomarker for aging in HIV/AIDS patients.

Science.gov (United States)

Kolgiri, Vaishali; Patil, Vinayak Wamanrao

The major complications of "treated" Human Immunodeficiency Virus (HIV) infection are cardiovascular disease, malignancy, renal disease, liver disease, bone disease, and perhaps neurological complications, which are phenomena of the normal aging process occurring at an earlier age in the HIV-infected population. The present study is aimed to explore protein carbonyl content as a biomarker for detecting oxidative DNA damage induced ART toxicity and/or accelerated aging in HIV/AIDS patients. To investigate the potential of carbonyl content as a biomarker for detecting oxidative Deoxyribonucleic acid (DNA) damage induced Antiretroviral Theraphy (ART) toxicity and/or accelerated aging in HIV/AIDS patients. In this case-control study a total 600 subjects were included. All subjects were randomly selected and grouped as HIV-negative (control group) (n=300), HIV-infected ART naive (n=100), HIV-infected on first line ART (n=100), and HIV-infected on second line ART (n=100). Seronegative control subjects were age- and sex-matched with the ART naive patients and the two other groups. Carbonyl protein was determined by the method described in Levine et al. DNA damage marker 8-OH-dG was determined using 8-hydroxy-2-deoxy Guanosine StressXpress ELA Kit by StressMarq Biosciences. Protein carbonyl content levels and oxidative DNA damage were significantly higher (paging in HIV/AIDS patients. Larger studies are warranted to elucidate the role of carbonyl content as a biomarker for premature aging in HIV/AIDS patients. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

Protective Effect of Brazilian Propolis against Liver Damage with Cholestasis in Rats Treated with α-Naphthylisothiocyanate

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Tadashi Nakamura

2013-01-01

Full Text Available We examined the protective effect of Brazilian propolis against liver damage with cholestasis in rats treated with α-naphthylisothiocyanate (ANIT in comparison with that of vitamin E (VE. Rats orally received Brazilian propolis ethanol extract (BPEE (25, 50, or 100 mg/kg, VE (250 mg/kg or vehicle at 12 h after intraperitoneal injection of ANIT (75 mg/kg and were killed 24 h after the injection. Vehicle-treated rats showed liver cell damage and cholestasis, judging from the levels of serum marker enzymes and components. The vehicle group had increased serum total cholesterol, triglyceride, phospholipid, and lipid peroxide levels, increased hepatic lipid peroxide, reduced glutathione, and ascorbic acid levels and myeloperoxidase activity, and decreased hepatic superoxide dismutase activity. BPEE (50 mg/kg administered to ANIT-treated rats prevented liver cell damage and cholestasis and attenuated these serum and hepatic biochemical changes except hepatic ascorbic acid, although administered BPEE (25 or 100 mg/kg was less effective. VE administered to ANIT-treated rats prevented liver cell damage, but not cholestasis, and attenuated increased serum lipid peroxide level, increased hepatic lipid peroxide level and myeloperoxidase activity, and decreased hepatic superoxide dismutase activity. These results indicate that BPEE protects against ANIT-induced liver damage with cholestasis in rats more effectively than VE.

Bile acids in radiation-induced diarrhea

International Nuclear Information System (INIS)

Arlow, F.L.; Dekovich, A.A.; Priest, R.J.; Beher, W.T.

1987-01-01

Radiation-induced bowel disease manifested by debilitating diarrhea is an unfortunate consequence of therapeutic irradiation for pelvic malignancies. Although the mechanism for this diarrhea is not well understood, many believe it is the result of damage to small bowel mucosa and subsequent bile acid malabsorption. Excess amounts of bile acids, especially the dihydroxy components, are known to induce water and electrolyte secretion and increase bowel motility. We have directly measured individual and total bile acids in the stool samples of 11 patients with radiation-induced diarrhea and have found bile acids elevated two to six times normal in eight of them. Our patients with diarrhea and increased bile acids in their stools had prompt improvement when given cholestyramine. They had fewer stools and returned to a more normal life-style

Protection of naturally occurring antioxidants against oxidative damages to protein

International Nuclear Information System (INIS)

Zhu Hongping; Zhang Zhaoxia; Hao Shumei; Wang Wenfeng; Yao Side

2006-01-01

One of the most compelling theories explaining age-related deterioration is the free radical theory of aging. It has been shown that reactive oxygen species are involved in oxidative damages to biomolecules and this is related to a number of diseases. Proteins, the second most abundant components of cells (next to water by weight), are now increasingly recognized as major biological targets of oxidative damages. Convincing evidences have indicated that damages to protein have been implicated in Alzheimer's disease, Parkinson's disease, cancer, and aging. Antioxidant has been the subject of great attention because they are known to lower the risk of cardiovascular and other diseases. Hydroxycinnamic acid derivatives (HCAs) are antioxidants abundant in tea, red wine, fruits, beverages and various medicinal plants. Results showed that they exhibit remarkable activity for scavenging oxidizing radicals and triplet states. The protective effects of four kinds of HCAs on oxidative damages to lysozyme were investigated in our lab. Protein damages induced by two different paradigms: riboflavin-sensitized photooxidation and hydroxyl ( . OH)-mediated oxidation, were investigated using polyacrylamide gel electrophoresis. HCAs were found to inhibit the cross-linking of protein induced by riboflavin-mediated photooxidation. HCAs also exhibited protection effect on lysozyme damage induced by γ-ray irradiation. The rate constants for quenching triplet state of riboflavin by lysozyme and HCAs were obtained using laser flash photolysis. The protective mechanism was proposed based on the dynamic study. HCAs were found to protect protein against oxidation by scavenging oxidizing species and repairing the damaged protein. (authors)

Beneficial effects of antioxidative lactic acid bacteria

Directory of Open Access Journals (Sweden)

Hisako Nakagawa

2017-01-01

Full Text Available Oxidative stress is caused by exposure to reactive oxygen intermediates. The oxidative damage of cell components such as proteins, lipids, and nucleic acids one of the important factors associated with diabetes mellitus, cancers and cardiovascular diseases. This occurs as a result of imbalance between the generations of oxygen derived radicals and the organism’s antioxidant potential. The amount of oxidative damage increases as an organism ages and is postulated to be a major causal factor of senescence. To date, many studies have focused on food sources, nutrients, and components that exert antioxidant activity in worms, flies, mice, and humans. Probiotics, live microorganisms that when administered in adequate amounts provide many beneficial effects on the human health, have been attracting growing interest for their health-promoting effects, and have often been administered in fermented milk products. In particular, lactic acid bacteria (LAB are known to conferre physiologic benefits. Many studies have indicated the antioxidative activity of LAB. Here we review that the effects of lactic acid bacteria to respond to oxidative stress, is connected to oxidative-stress related disease and aging.

Nondestructive damage detection and evaluation technique for seismically damaged structures

Science.gov (United States)

Adachi, Yukio; Unjoh, Shigeki; Kondoh, Masuo; Ohsumi, Michio

1999-02-01

The development of quantitative damage detection and evaluation technique, and damage detection technique for invisible damages of structures are required according to the lessons from the 1995 Hyogo-ken Nanbu earthquake. In this study, two quantitative damage sensing techniques for highway bridge structures are proposed. One method is to measure the change of vibration characteristics of the bridge structure. According to the damage detection test for damaged bridge column by shaking table test, this method can successfully detect the vibration characteristic change caused by damage progress due to increment excitations. The other method is to use self-diagnosis intelligent materials. According to the reinforced concrete beam specimen test, the second method can detect the damage by rupture of intelligent sensors, such as optical fiber or carbon fiber reinforced plastic rod.

The Protective Role of Hyaluronic Acid in Cr(VI-Induced Oxidative Damage in Corneal Epithelial Cells

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Wei Wu

2017-01-01

Full Text Available Cr(VI exposure could produce kinds of intermediates and reactive oxygen species, both of which were related to DNA damage. Hyaluronan (HA has impressive biological functions and was reported to protect corneal epithelial cells against oxidative damage induced by ultraviolet B, benzalkonium chloride, and sodium lauryl sulfate. So the aim of our study was to investigate HA protection on human corneal epithelial (HCE cells against Cr(VI-induced toxic effects. The HCE cell lines were exposed to different concentrations of K2Cr2O7 (1.875, 3.75, 7.5, 15.0, and 30 μM or a combination of K2Cr2O7 and 0.2% HA and incubated with different times (15 min, 30 min, and 60 min. Our data showed that Cr(VI exposure could cause decreased cell viability, increased DNA damage, and ROS generation to the HCE cell lines. But incubation of HA increased HCE cell survival rates and decreased DNA damage and ROS generation induced by Cr(VI in a dose- and time-dependent manner. We report for the first time that HA can protect HCE cells against the toxicity of Cr(VI, indicating that it will be a promising therapeutic agent to corneal injuries caused by Cr(VI.

A conceptual framework: redifining forests soil's critical acid loads under a changing climate

Science.gov (United States)

Steven G. McNulty; Johnny L. Boggs

2010-01-01

Federal agencies of several nations have or are currently developing guidelines for critical forest soil acid loads. These guidelines are used to establish regulations designed to maintain atmospheric acid inputs below levels shown to damage forests and streams. Traditionally, when the critical soil acid load exceeds the amount of acid that the ecosystem can absorb, it...

Back to acid soil fields

NARCIS (Netherlands)

Carvalho, Geraldo; Schaffert, Robert Eugene; Malosetti Zunin, Marcos; Eeuwijk, van Fred

2016-01-01

Aluminum (Al) toxicity damages plant roots and limits crop production on acid soils, which comprise up to 50% of the world's arable lands. A major Al tolerance locus on chromosome 3, AltSB, controls aluminum tolerance in sorghum [Sorghum bicolor (L.) Moench] via SbMATE, an Al-activated plasma

Metabolic pathways regulated by abscisic acid, salicylic acid and γ-aminobutyric acid in association with improved drought tolerance in creeping bentgrass (Agrostis stolonifera).

Science.gov (United States)

Li, Zhou; Yu, Jingjin; Peng, Yan; Huang, Bingru

2017-01-01

Abscisic acid (ABA), salicylic acid (SA) and γ-aminobutyric acid (GABA) are known to play roles in regulating plant stress responses. This study was conducted to determine metabolites and associated pathways regulated by ABA, SA and GABA that could contribute to drought tolerance in creeping bentgrass (Agrostis stolonifera). Plants were foliar sprayed with ABA (5 μM), GABA (0.5 mM) and SA (10 μM) or water (untreated control) prior to 25 days drought stress in controlled growth chambers. Application of ABA, GABA or SA had similar positive effects on alleviating drought damages, as manifested by the maintenance of lower electrolyte leakage and greater relative water content in leaves of treated plants relative to the untreated control. Metabolic profiling showed that ABA, GABA and SA induced differential metabolic changes under drought stress. ABA mainly promoted the accumulation of organic acids associated with tricarboxylic acid cycle (aconitic acid, succinic acid, lactic acid and malic acid). SA strongly stimulated the accumulation of amino acids (proline, serine, threonine and alanine) and carbohydrates (glucose, mannose, fructose and cellobiose). GABA enhanced the accumulation of amino acids (GABA, glycine, valine, proline, 5-oxoproline, serine, threonine, aspartic acid and glutamic acid) and organic acids (malic acid, lactic acid, gluconic acid, malonic acid and ribonic acid). The enhanced drought tolerance could be mainly due to the enhanced respiration metabolism by ABA, amino acids and carbohydrates involved in osmotic adjustment (OA) and energy metabolism by SA, and amino acid metabolism related to OA and stress-defense secondary metabolism by GABA. © 2016 Scandinavian Plant Physiology Society.

Analysis of ribo- and deoxyribonucleic acids using ionpair-reversed-phase liquid-chromatography electrospray-mass spectrometry

International Nuclear Information System (INIS)

Hoelzl, G.

2002-10-01

The fast progress in natural sciences like biology, biochemistry, medicine or genetics make high demands on the analytical chemistry. The on-line coupling of ionpair-reversed phase-liquid chromatography (IP-RP-HPLC) to mass spectrometry (MS) becomes more and more the method of choice for the analysis of biomolecules. The success is based on the introduction of soft ionization methods, like electrospray ionization (ESI), which allows the transfer of intact biopolymers into the gasphase. This combination enables the on-line separation of complex biological mixtures with additional identification of the compounds by their molecular mass. The first part describes the development of a new ionsource, which combines the advantages of a micro-ESI- and a nanospray-source. In combination with additional optimization of the chromatographic conditions the new ionsource showed an improvement of the quality of the spectra by a factor of 5 and a stability of the ionspray by a factor of 2, which resulted in an overall improvement of sensitivity by a factor of 10 for the HPLC-MS system. The second part describes the quality control of synthetic RNA molecules. Using IP-RP-HPLC-ESI-MS it was possible to separate failure sequences and derivatives in raw products of short synthetic RNAs. The derivatives were formed of protecting groups, which were not removed during the deprotection step. The analysis of coupling products of the synthesis of aminoacylated transfer RNAs showed a derivative, which was formed by the addition of the used coupling reagent N-(3-dimethylaminopropyl)N'-ethylcarbodiimide (EDC). The identification of the derivatives led to the optimization of the reaction conditions which resulted in the synthesis of the wanted transfer RNA without any additional derivatives. Another experiment involved the fragmentation of RNA molecules. Tandem mass spectrometry provides the opportunity to determine the sequence of nucleic acids. Fragmentation experiments showed different

Hepatitis B virus X protein (HBx)-induced abnormalities of nucleic acid metabolism revealed by (1)H-NMR-based metabonomics.

Science.gov (United States)

Dan Yue; Zhang, Yuwei; Cheng, Liuliu; Ma, Jinhu; Xi, Yufeng; Yang, Liping; Su, Chao; Shao, Bin; Huang, Anliang; Xiang, Rong; Cheng, Ping

2016-04-14

Hepatitis B virus X protein (HBx) plays an important role in HBV-related hepatocarcinogenesis; however, mechanisms underlying HBx-mediated carcinogenesis remain unclear. In this study, an NMR-based metabolomics approach was applied to systematically investigate the effects of HBx on cell metabolism. EdU incorporation assay was conducted to examine the effects of HBx on DNA synthesis, an important feature of nucleic acid metabolism. The results revealed that HBx disrupted metabolism of glucose, lipids, and amino acids, especially nucleic acids. To understand the potential mechanism of HBx-induced abnormalities of nucleic acid metabolism, gene expression profiles of HepG2 cells expressing HBx were investigated. The results showed that 29 genes involved in DNA damage and DNA repair were differentially expressed in HBx-expressing HepG2 cells. HBx-induced DNA damage was further demonstrated by karyotyping, comet assay, Western blotting, immunofluorescence and immunohistochemistry analyses. Many studies have previously reported that DNA damage can induce abnormalities of nucleic acid metabolism. Thus, our results implied that HBx initially induces DNA damage, and then disrupts nucleic acid metabolism, which in turn blocks DNA repair and induces the occurrence of hepatocellular carcinoma (HCC). These findings further contribute to our understanding of the occurrence of HCC.

Dose-rate and oxygen effects in models of lipid membranes: linoleic acid

Energy Technology Data Exchange (ETDEWEB)

Raleigh, J A; Kremers, W; Gaboury, B [Atomic Energy of Canada Ltd., Pinawa, Manitoba. Whiteshell Nuclear Research Establishment

1977-03-01

Cellular membranes have been suggested as possible loci for the development of the oxygen effect in radiobiology. Unsaturated lipids from membranes are subject to very efficient radiation-induced peroxidation, and the deleterious effects generally associated with lipid autoxidation could be initiated by ionizing radiation. Oxidative damage in lipids was characterized not only by high yields but also by a profound dose-rate effect. At dose-rates of x irradiation below 100 rad/min, a very sharp rise occurred in oxidative damage. This damage has been quantified spectrophotometrically in terms of diene conjugation (O.D. 234 mm) and chromatographically in terms of specific 9- and 13-hydroperoxide formation in linoleic acid micelles. Radical scavenging experiments indicated that hydroxyl radical attack initiated the oxidative damage. Dimethyl sulphoxide is exceptional in that it did not protect, but sensitized, linoleic acid to radiation-induced peroxidation. The yields of hydroperoxides were substantial (G = 10 to 40) and could be related to biological changes known to be effected by autoxidizing lipids.

DNA barcode of coastal alga ( Chlorella sorokiniana ) from Ago ...

African Journals Online (AJOL)

Five different loci 18S, UPA, rbcl, ITS and tufA were tested for their use as deoxyribonucleic acid (DNA) barcode in this study. Although the UPA primers were designed to amplify all phototrophic algae and cyanobacteria, UPA and 18S did not amplified at all for the genus Chlorella while ITS1, ITS2 rDNA and rbcL markers ...

Analysis of the Cellular and Molecular Mechanisms Which Underlie Sensitivity to Bacterial Endotoxin and Early Tolerance

Science.gov (United States)

1992-06-24

hydrolase enzyme bp- base pairs BSA- bovine serum albumin cAMP- cyclic adenosine S’-monophosphate cDNA- complementary deoxyribonucleic acid C02...tachycardia, tachypnea, hypertriglyceridemia, thrombocytopenia, metabolic acidosis , acute renal failure, hepatic failure, acute respiratory distress...bilirubin, lactate (which indicates an ameliorating effect on metabolic acidosis ), and to bring about an increase in the mean arterial pressure in balxxms

Max Planck Institute for Radiation Chemistry, Muelheim a.d. Ruhr

International Nuclear Information System (INIS)

Anon.

1991-01-01

The Institute carriers out research in the field of radiation chemistry, which is understood as a field of science combining photochemistry and radiation chemistry. The research programme focuses on: the radiation chemistry of the deoxyribonucleic acids (DNA), DNA constituents, and DNA model compounds; photobiochemistry and fundamentals of photobiology; organic and organometallic photochemistry, particularly reaction mechanisms and synthesis; photophysics. (orig.) [de

Radiation damage of proteins in the solid state: changes of amino acid composition in catalase

International Nuclear Information System (INIS)

Baumeister, W.; Hahn, M.; Seredynski, J.; Herbertz, L.M.

1976-01-01

Catalase has been irradiated with 100 keV electrons under conditions simulating the hazards of electron microscopic imaging. Amino acid analysis reveals a definite pattern of amino acid destruction which is well correlated with the particular chemical structures of amino acid side chains. This pattern appears to be distinctly different from the sensitivity pattern for monoamino acid systems which is ascribed to intramolecular energy transfer and selective attack of liberated radicals

Effect of aqueous extract of saffron (crocus sativus L.) against gamma radiation-induced skeletal muscles damage in rats

International Nuclear Information System (INIS)

El-Tahawy, N.A; Said, U.Z

2010-01-01

Muscular strength is important in sport as well as in daily activities. Reactive oxygen species (ROS) and oxidative damage are the most important factors in radiation-induced acute damage to muscle tissue. Saffron, obtained from dried stigmas of Crocus sativus L. (Iridaceae), is a highly valued spice, commonly used in flavouring and food colouring in different parts of the world and is known to possess the richest source of carotenoids. The present study was designed to investigate the efficacy of an aqueous extract of saffron to protect against radiation-induced oxidative damage in rat's skeletal muscle. Saffron was supplemented orally, via gavages to rats at a dose of 80 mg/ kg body wt/ day for 2 week pre- and 1 week post-exposure to 5 Gy (one shot dose) of whole body gamma-irradiation. Animals were sacrificed 1, 2 and 3 weeks post radiation exposure. The results revealed that whole body gamma-irradiation of rats induce oxidative stress in skeletal muscles obvious by significant elevation in the level of thiobarbituric acid reactive substances associated with significant decreases in superoxide dismutase and catalase activities. Also, radiation-induces skeletal muscles damage evidenced by significant decreases in the level of pyruvic acid, creatine phosphokinase, glutamate dehydrogenase and glucose-6-phosphate dehydrogenase activities as well as significant increases in lactic acid, total iron, and copper and calcium levels. Saffron treated-irradiated rats showed significantly less severe damage and remarkable improvement in all the measured parameters, compared to irradiated rats. It could be concluded that saffron by attenuating radiation-induced oxidative stress might play a role in maintaining skeletal muscle integrity.

Mannitol can mitigate negative effects of simulated acid mist and fluoranthene in juvenile Japanese red pine (P. densiflora Sieb. et Zucc.)

International Nuclear Information System (INIS)

Oguntimehin, Ilemobayo; Bandai, Sayuri; Sakugawa, Hiroshi

2013-01-01

The negative health effects of simulated acid mists and fluoranthene on juvenile Japanese red pine were investigated, and the methods of protection from these pollutants were examined. The needle gas exchange, chlorophyll fluorescence, chemical contents and visual damage to needles caused by acid mist applied alone or its conjunction with fluoranthene were investigated over 60 d and 20 d, respectively. Acid mist at pH 2 and 3 caused physiological and visual damage, which was enhanced by the addition of fluoranthene to the mist. However, fluoranthene and acid mist at pH 4 and 5 showed only minor effects. These findings indicate that acid mist may be more harmful to pine trees if it occurs in conjunction with polycyclic aromatic hydrocarbons. Moreover, suppression of the singular and additive effects of these compounds was achieved using mannitol, which may be widely applicable to suppression of reactive oxygen species-mediated plant damage. -- Highlights: ► We evaluate acid mist alone and acid mist plus fluoranthene effects on pine needles. ► Acid mist more damages pine needles if fluoranthene was additionally sprayed. ► The suppression of the mixture of pollutants effects are achieved with mannitol. ► Mannitol could be useful for protecting pine trees from air pollutants. -- Mannitol could be useful for protecting pine trees and other plants from air pollutants

USGS Tracks Acid Rain

Science.gov (United States)

Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.

1995-01-01

The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

Uric acid, an important antioxidant contributing to survival in termites

Science.gov (United States)

Tasaki, Eisuke; Sakurai, Hiroki; Nitao, Masaru; Matsuura, Kenji; Iuchi, Yoshihito

2017-01-01

Reactive oxygen species (ROS) are generated spontaneously in all organisms and cause oxidative damage to biomolecules when present in excess. Accumulated oxidative damage accelerates aging; enhanced antioxidant capacity may be a positive factor for longevity. Recently, numerous studies of aging and longevity have been performed using short-lived animals, however, longevity mechanisms remain unknown. Here we show that a termite Reticulitermes speratus that is thought to be long-lived eusocial insect than other solitary insects uses large quantities of uric acid as an antioxidant against ROS. We demonstrated that the accumulation of uric acid considerably increases the free radical-scavenging activity and resistance against ultraviolet-induced oxidative stress in laboratory-maintained termites. In addition, we found that externally administered uric acid aided termite survival under highly oxidative conditions. The present data demonstrates that in addition to nutritional and metabolic roles, uric acid is an essential antioxidant for survival and contributes significantly to longevity. Uric acid also plays important roles in primates but causes gout when present in excess in humans. Further longevity studies of long-lived organisms may provide important breakthroughs with human health applications. PMID:28609463

Ultrasonic Measurement of Corrosion Depth Development in Concrete Exposed to Acidic Environment

Directory of Open Access Journals (Sweden)

Fan Yingfang

2012-01-01

Full Text Available Corrosion depth of concrete can reflect the damage state of the load-carrying capacity and durability of the concrete structures servicing in severe environment. Ultrasonic technology was studied to evaluate the corrosion depth quantitatively. Three acidic environments with the pH level of 3.5, 2.5, and 1.5 were simulated by the mixture of sulfate and nitric acid solutions in the laboratory. 354 prism specimens with the dimension of 150 mm × 150 mm × 300 mm were prepared. The prepared specimens were first immersed in the acidic mixture for certain periods, followed by physical, mechanical, computerized tomography (CT and ultrasonic test. Damage depths of the concrete specimen under different corrosion states were obtained from both CT and ultrasonic test. Based on the ultrasonic test, a bilinear regression model is proposed to estimate the corrosion depth. It is shown that the results achieved by ultrasonic and CT test are in good agreement with each other. Relation between the corrosion depth of concrete specimen and the mechanical indices such as mass loss, compressive strength, and elastic modulus is discussed in detail. It can be drawn that the ultrasonic test is a reliable nondestructive way to measure the damage depth of concrete exposed to acidic environment.

Assessing the costs and market impacts of carbon sequestration, climate change, and acid rain

International Nuclear Information System (INIS)

Callaway, J.M.

2000-03-01

This thesis provides fourteen journal articles and papers. Thirteen of these papers were published in referred journals, covering environmental economics, policy modelling, policy analysis, and the physical sciences. One paper was published as a USDA Forest Service research report. The papers in the thesis are divided into three topical areas: 1) Section 2: The Economics of Carbon Sequestration. Eight papers plus Appendix A of the thesis cover the development and application of models to estimate the economic costs and management consequences of policies to sequester carbon emissions by planting trees on agricultural land in the US or through more intensive forest management. 2) Section 3: The Economics of Climate Change Damages. Two papers of the thesis cover the development of models that can be used to estimate the market and nonmarket damages associated with the impacts of climate change on water resources in the US. 3) Section 4: The Economics of Acid Rain Damages. Three papers in the thesis examine the methods that were developed to estimate the damages due to acid rain in the US by the National Acid Precipitation Assessment Program (NAPAP) and discuss more generally the role of economic policy analysis in this assessment. (EHS)

Spinal interleukin-10 therapy to treat peripheral neuropathic pain.

Science.gov (United States)

Milligan, Erin D; Penzkover, Kathryn R; Soderquist, Ryan G; Mahoney, Melissa J

2012-01-01

  Current research indicates that chronic peripheral neuropathic pain includes a role for glia and the actions of proinflammatory factors. This review briefly discusses the glial and cytokine responses that occur following peripheral nerve damage in support of utilizing anti-inflammatory cytokine interleukin-10 (IL-10) therapy to suppress chronic peripheral neuropathic pain. SPINAL NONVIRAL INTERLEUKIN-10 GENE THERAPY:  IL-10 is one of the most powerful endogenous counter-regulators of proinflammatory cytokine function that acts in the nervous system. Subarachnoid (intrathecal) spinal injection of the gene encoding IL-10 delivered by nonviral vectors has several advantages over virally mediated gene transfer methods and leads to profound pain relief in several animal models. NONVIRAL GENE DELIVERY:  Lastly, data are reviewed that nonviral deoxyribonucleic acid (DNA) encapsulated by a biologically safe copolymer, poly(lactic-co-glycolic) acid (PLGA), thought to protect DNA, leads to significantly improved therapeutic gene transfer in animal models, which additionally and significantly extends pain relief.   The impact of these early studies exploring anti-inflammatory genes emphasizes the exceptional therapeutic potential of new biocompatible intrathecal nonviral gene delivery approaches such as PLGA microparticles. Ultimately, ongoing expression of therapeutic genes is a viable option to treat chronic neuropathic pain in the clinic. © 2012 International Neuromodulation Society.

Phagocytic response of astrocytes to damaged neighboring cells.

Directory of Open Access Journals (Sweden)

Nicole M Wakida

Full Text Available This study aims to understand the phagocytic response of astrocytes to the injury of neurons or other astrocytes at the single cell level. Laser nanosurgery was used to damage individual cells in both primary mouse cortical astrocytes and an established astrocyte cell line. In both cases, the release of material/substances from laser-irradiated astrocytes or neurons induced a phagocytic response in near-by astrocytes. Propidium iodide stained DNA originating from irradiated cells was visible in vesicles of neighboring cells, confirming phagocytosis of material from damaged cortical cells. In the presence of an intracellular pH indicator dye, newly formed vesicles correspond to acidic pH fluorescence, thus suggesting lysosome bound degradation of cellular debris. Cells with shared membrane connections prior to laser damage had a significantly higher frequency of induced phagocytosis compared to isolated cells with no shared membrane. The increase in phagocytic response of cells with a shared membrane occurred regardless of the extent of shared membrane (a thin filopodial connection vs. a cell cluster with significant shared membrane. In addition to the presence (or lack of a membrane connection, variation in phagocytic ability was also observed with differences in injury location within the cell and distance separating isolated astrocytes. These results demonstrate the ability of an astrocyte to respond to the damage of a single cell, be it another astrocyte, or a neuron. This single-cell level of analysis results in a better understanding of the role of astrocytes to maintain homeostasis in the CNS, particularly in the sensing and removal of debris in damaged or pathologic nervous tissue.

Automated Damage Onset Analysis Techniques Applied to KDP Damage and the Zeus Small Area Damage Test Facility

International Nuclear Information System (INIS)

Sharp, R.; Runkel, M.

1999-01-01

Automated damage testing of KDP using LLNL's Zeus automated damage test system has allowed the statistics of KDP bulk damage to be investigated. Samples are now characterized by the cumulative damage probability curve, or S-curve, that is generated from hundreds of individual test sites per sample. A HeNe laser/PMT scatter diagnostic is used to determine the onset of damage at each test site. The nature of KDP bulk damage is such that each scatter signal may possess many different indicators of a damage event. Because of this, the determination of the initial onset for each scatter trace is not a straightforward affair and has required considerable manual analysis. The amount of testing required by crystal development for the National Ignition Facility (NIF) has made it impractical to continue analysis by hand. Because of this, we have developed and implemented algorithms for analyzing the scatter traces by computer. We discuss the signal cleaning algorithms and damage determination criteria that have lead to the successful implementation of a LabView based analysis code. For the typical R/1 damage data set, the program can find the correct damage onset in more than 80% of the cases, with the remaining 20% being left to operator determination. The potential time savings for data analysis is on the order of ∼ 100X over manual analysis and is expected to result in the savings of at least 400 man-hours over the next 3 years of NIF quality assurance testing

Gymnaster koraiensis and its major components, 3,5-di-O-caffeoylquinic acid and gymnasterkoreayne B, reduce oxidative damage induced by tert-butyl hydroperoxide or acetaminophen in HepG2 cells

Directory of Open Access Journals (Sweden)

Eun Hye Jho

2013-10-01

Full Text Available We investigated the protective effects of Gymnaster koraiensisagainst oxidative stress-induced hepatic cell damage. We usedtwo different cytotoxicity models, i.e., the administration oftert-butyl hydroperoxide (t-BHP and acetaminophen, in HepG2cells to evaluate the protective effects of G. koraiensis. The ethylacetate (EA fraction of G. koraiensis and its major compound,3,5-di-O-caffeoylquinic acid (DCQA, exerted protective effectsin the t-BHP-induced liver cytotoxicity model. The EA fractionand DCQA ameliorated t-BHP-induced reductions in GSHlevels and exhibited free radical scavenging activity. The EAfraction and DCQA also significantly reduced t-BHP-inducedDNA damage in HepG2 cells. Furthermore, the hexane fractionof G. koraiensis and its major compound, gymnasterkoreayne B(GKB, exerted strong hepatoprotection in the acetaminopheninducedcytotoxicity model. CYP 3A4 enzyme activity wasstrongly inhibited by the extract, hexane fraction, and GKB. Thehexane fraction and GKB ameliorated acetaminophen-inducedreductions in GSH levels and protected against cell death. [BMBReports 2013; 46(10: 513-518

Inactivation of carotenoid-producing and albino strains of Neurospora crassa by visible light, blacklight, and ultraviolet radiation

International Nuclear Information System (INIS)

Blanc, P.L.; Tuveson, R.W.; Sargent, M.L.

1976-01-01

Suspensions of Neurospora crassa conidia were inactivated by blacklight (BL) radiation (300 to 425 nm) in the absence of exogenous photosensitizing compounds. Carotenoid-containing wild-type conidia were less sensitive to BL radiation than albino conidia, showing a dose enhancement factor (DEF) of 1.2 for dose levels resulting in less than 10 percent survival. The same strains were about equally sensitive to shortwave ultraviolet (uv) inactivation. The kinetics of BL inactivation are similar to those of photodynamic inactivation by visible light in the presence of a photosensitizing dye (methylene blue). Only limited inactivation by visible light in the absence of exogenous photosensitizers was observed. BL and UV inactivations are probably caused by different mechanisms since wild-type conidia are only slightly more resistant to BL radiation (DEF = 1.2 at 1.0 percent survival) than are conidia from a uv-sensitive strain (upr-1, uvs-3). The BL-induced lethal lesions are probably not cyclobutyl pyrimidine dimers since BL-inactivated Haemophilus influenzae transforming deoxyribonucleic acid is not photoreactivated by N. crassa wild-type enzyme extracts, whereas uv-inactivated transforming deoxyribonucleic acid is photoreactivable with this treatment

Unusual binding of ursodeoxycholic acid to ileal bile acid binding protein: role in activation of FXRα[S

Science.gov (United States)

Fang, Changming; Filipp, Fabian V.; Smith, Jeffrey W.

2012-01-01

Ursodeoxycholic acid (UDCA, ursodiol) is used to prevent damage to the liver in patients with primary biliary cirrhosis. The drug also prevents the progression of colorectal cancer and the recurrence of high-grade colonic dysplasia. However, the molecular mechanism by which UDCA elicits its beneficial effects is not entirely understood. The aim of this study was to determine whether ileal bile acid binding protein (IBABP) has a role in mediating the effects of UDCA. We find that UDCA binds to a single site on IBABP and increases the affinity for major human bile acids at a second binding site. As UDCA occupies one of the bile acid binding sites on IBABP, it reduces the cooperative binding that is often observed for the major human bile acids. Furthermore, IBABP is necessary for the full activation of farnesoid X receptor α (FXRα) by bile acids, including UDCA. These observations suggest that IBABP may have a role in mediating some of the intestinal effects of UDCA. PMID:22223860

Acid precipitation and forest vegetation

Energy Technology Data Exchange (ETDEWEB)

Tamm, C O; Cowling, E B

1977-04-01

Effects of acidic precipitation on forest vegetation may be classified as being either direct or indirect. Among the most important direct effects are damage to protective cuticular layers, interference with normal functioning of guard cells, poisoning of plant cells after diffusion of acidic substances through stomata or cuticle and interference with reproductive processes. Indirect effects include accelerated leaching of substances from foliar organs, increased susceptibility to drought and other environmental stress factors, and alteration of symbiotic associations and host-parasite interactions. The potential importance of nutrient uptake through foliage and the need to understand atmosphere-plant-soil interactions are stressed.

Quinacrine pretreatment reduces microwave-induced neuronal damage by stabilizing the cell membrane

Science.gov (United States)

Ding, Xue-feng; Wu, Yan; Qu, Wen-rui; Fan, Ming; Zhao, Yong-qi

2018-01-01

Quinacrine, widely used to treat parasitic diseases, binds to cell membranes. We previously found that quinacrine pretreatment reduced microwave radiation damage in rat hippocampal neurons, but the molecular mechanism remains poorly understood. Considering the thermal effects of microwave radiation and the protective effects of quinacrine on heat damage in cells, we hypothesized that quinacrine would prevent microwave radiation damage to cells in a mechanism associated with cell membrane stability. To test this, we used retinoic acid to induce PC12 cells to differentiate into neuron-like cells. We then pretreated the neurons with quinacrine (20 and 40 mM) and irradiated them with 50 mW/cm2 microwaves for 3 or 6 hours. Flow cytometry, atomic force microscopy and western blot assays revealed that irradiated cells pretreated with quinacrine showed markedly less apoptosis, necrosis, and membrane damage, and greater expression of heat shock protein 70, than cells exposed to microwave irradiation alone. These results suggest that quinacrine stabilizes the neuronal membrane structure by upregulating the expression of heat shock protein 70, thus reducing neuronal injury caused by microwave radiation. PMID:29623929

Influence of oxidative stress on disease development

Directory of Open Access Journals (Sweden)

Božić Tatjana

2013-01-01

complications of diabetes mellitus. Since inducible nitrogen-oxide synthesis launches processes that stimulate apoptosis of cerebral endothelial cells, and superoxide-anion radicals, hypochloric acid and hydrogen peroxide damage the parenchyma of an ischemic brain and biomacromolecules (causing lipid peroxidation, oxidation of proteins and deoxyribonucleic acid, brain damage occurs during cerebral ischemia and reperfusion. [Projekat Ministarstva nauke Republike Srbije, br. 173034, br. 175061 i br. 31085

Induced resistance to Helicoverpa armigera through exogenous application of jasmonic acid and salicylic acid in groundnut, Arachis hypogaea.

Science.gov (United States)

War, Abdul Rashid; Paulraj, Michael Gabriel; Ignacimuthu, Savarimuthu; Sharma, Hari Chand

2015-01-01

Induced resistance to Helicoverpa armigera through exogenous application of jasmonic acid (JA) and salicylic acid (SA) was studied in groundnut genotypes (ICGV 86699, ICGV 86031, ICG 2271 and ICG 1697) with different levels of resistance to insects and the susceptible check JL 24 under greenhouse conditions. Activities of oxidative enzymes and the amounts of secondary metabolites and proteins were quantified at 6 days after JA and SA application/insect infestation. Data were also recorded on plant damage and H. armigera larval weights and survival. Higher levels of enzymatic activities and amounts of secondary metabolites were observed in the insect-resistant genotypes pretreated with JA and then infested with H. armigera than in JL 24. The insect-resistant genotypes suffered lower insect damage and resulted in poor survival and lower weights of H. armigera larvae than JL 24. In some cases, JA and SA showed similar effects. JA and SA induced the activity of antioxidative enzymes in groundnut plants against H. armigera, and reduced its growth and development. However, induced response to application of JA was greater than to SA, and resulted in reduced plant damage, and larval weights and survival, suggesting that induced resistance can be used as a component of pest management in groundnut. © 2014 Society of Chemical Industry.

An immunochemical approach to the study of DNA damage and repair

International Nuclear Information System (INIS)

Wallace, S.S.; Erlanger, B.F.

1992-05-01

The overall objective of this project has been to develop immunochemical methods to quantitate unique DNA base damages in order to facilitate studies on radiation-induced damage production and repair. Specifically, we have been using antibodies raised to damaged bases to quantitate unique lesions in model systems in order to evaluate their potential biological consequences. Our approach has been to synthesize modified nucleotides or nucleosides, conjugate them to protein carriers, and use the conjugates as immunogens in rabbits or to prepare monoclonal antibodies. We have been studying damages that are stable radiolysis products found in X-irradiated DNA and thus of potential biological consequence. Our aim is to build an in vitro and in vivo data base on the interactions between model DNA lesions and such cellular enzymes as DNA polymerases and repair endonucleases. Initial studies have focused on pyrimidine ring saturation products (thymine glycol.and dihydrothymine), products resulting from ring fragmentation or base loss (urea, Β-ureidoisobutyric acid, abasic sites), 7-hydro-8-oxopurines, and more recently, cytosine radiolysis products. These modified bases serve as useful models for examining the potential lethal and/or mutagenic (carcinogenic) effects of the products of DNA radiolysis

The spatial distribution of forest damages in southeastern Finland

Energy Technology Data Exchange (ETDEWEB)

Jokinen, J.; Maekinen, E.; Meinander, O.; Haarala, S. [Finnish Meteorological Inst., Helsinki (Finland)

1995-12-31

Up to the present time scientists researching the causes of the vast areas of forest damages observed in Europe and North America have presented many different hypotheses. Among the first explanations was the damaging effect of acid rain. Some researchers claimed that of all air pollutants ozone was the most important damaging agent. The stress theory emphasizes the interaction of nitrogen oxides and sulphur dioxide with oxidants, hydrocarbons and heavy metals to be the main cause of toxic effects. In addition to above-mentioned theories, projects carried out by the Finnish Meteorological Institute (FMI) have revealed that under northern conditions coniferous forests have been damaged even in situations where the emissions consist of sulphur and nitrogen compounds occurring together. This theory postulates that the interaction of the above pollutants may be responsible by themselves for the effects on coniferous forests. The interaction is supposed to cause damages by two different mechanisms, namely, by causing direct toxic effects or through wintering failures. These mechanisms are indicated by the total nitrogen and sulphur concentration relationships of the needles. In the first case both sulphur dioxide and nitrogen oxides occur at such a high levels in the air that they cause direct damages, while in the second case sulphur dioxide concentration, in particular, is lower and both compounds can then be used as nutrients causing nutrient imbalance and a loss of wintering hardiness of the needles. The study area in these projects was southeastern Finland, which is one of the most polluted areas in our country. Domestic emissions from the paper and pulp industry, as well as the Russian emissions (e g. from the Leningrad region) affect this area. The aim of this study was to test the sulphur-nitrogen hypothesis using data collected from the Kymi province, S.E. Finland. (author)

The spatial distribution of forest damages in southeastern Finland

Energy Technology Data Exchange (ETDEWEB)

Jokinen, J; Maekinen, E; Meinander, O; Haarala, S [Finnish Meteorological Inst., Helsinki (Finland)

1996-12-31

Up to the present time scientists researching the causes of the vast areas of forest damages observed in Europe and North America have presented many different hypotheses. Among the first explanations was the damaging effect of acid rain. Some researchers claimed that of all air pollutants ozone was the most important damaging agent. The stress theory emphasizes the interaction of nitrogen oxides and sulphur dioxide with oxidants, hydrocarbons and heavy metals to be the main cause of toxic effects. In addition to above-mentioned theories, projects carried out by the Finnish Meteorological Institute (FMI) have revealed that under northern conditions coniferous forests have been damaged even in situations where the emissions consist of sulphur and nitrogen compounds occurring together. This theory postulates that the interaction of the above pollutants may be responsible by themselves for the effects on coniferous forests. The interaction is supposed to cause damages by two different mechanisms, namely, by causing direct toxic effects or through wintering failures. These mechanisms are indicated by the total nitrogen and sulphur concentration relationships of the needles. In the first case both sulphur dioxide and nitrogen oxides occur at such a high levels in the air that they cause direct damages, while in the second case sulphur dioxide concentration, in particular, is lower and both compounds can then be used as nutrients causing nutrient imbalance and a loss of wintering hardiness of the needles. The study area in these projects was southeastern Finland, which is one of the most polluted areas in our country. Domestic emissions from the paper and pulp industry, as well as the Russian emissions (e g. from the Leningrad region) affect this area. The aim of this study was to test the sulphur-nitrogen hypothesis using data collected from the Kymi province, S.E. Finland. (author)

Processing of Natural Signals like EMG for Person Identification using NUFB-GMM

OpenAIRE

Suresh M; P G Krishnamohan; Mallikarjun S Holi

2014-01-01

Physiological signals like Electrocardiogram(ECG) and Electroencephalogram(EEG), including deoxyribonucleic acid(DNA) are person specific and distinct for different persons. The motor unit firing pattern, motor unit recruitment order and characteristics of muscle changing from person to person, and therefore Electromyogram (EMG) can be used for person identification. EMG records obtained from a single channel data acquisition system are used to develop person identification system. Non-unifor...

Hypoxia Inducible Factor 1 (HIF1) Activation in U87 Glioma Cells Involves a Decrease in Reactive Oxygen Species Production and Protein Kinase C Activity

Science.gov (United States)

1998-06-29

Curcumin DFX Desferrioxamine DNA Deoxyribonucleic Acid DPI Diphenyliodinium DPPD Diphenylphenylenediamine DTH Dithionite EMSA Electrophoretic mobility shift... neuroprotective effects (Fern et al., 1996, Morishita et al., 1 1997). The identification of a hypoxia inducible transcription factor known as HIF-1 (Semenza...derived EPO in the eNS neuroprotective response to hypoxia. Cloning of the human and murine EPO gene, the availability of a convenient EPa producing

Curcumin Attenuates Gamma Radiation Induced Intestinal Damage in Rats

International Nuclear Information System (INIS)

EI-Tahawy, N.A.

2009-01-01

Small Intestine exhibits numerous morphological and functional alterations during radiation exposure. Oxidative stress, a factor implicated in the intestinal injury may contribute towards some of these alterations. The present work was designed to evaluate the efficacy of curcumin, a yellow pigment of turmeric on y-radiation-induced oxidative damage in the small intestine by measuring alterations in the level of thiobarbituric acid reactive substances (TSARS), serotonin metabolism, catecholamine levels, and monoamine oxidase (MAO) activity in parallel to changes in the architecture of intestinal tissues. In addition, monoamine level, MAO activity and TSARS level were determined in the serum. Curcumin was supplemented orally via gavages, to rats at a dose of (45 mg/ Kg body wt/ day) for 2 weeks pre-irradiation and the last supplementation was 30 min pre exposure to 6.5 Gy gamma radiations (applied as one shot dose). Animals were sacrificed on the 7th day after irradiation. The results demonstrated that, whole body exposure of rats to ionizing radiation has induced oxidative damage in small intestine obvious by significant increases of TSARS content, MAO activity and 5-hydroxy indole acetic acid (5-HIAA) and by significant decreases of serotonin (5-HT), dopamine (DA), norepinephrine (NE) and epinephrine (EPI) levels. In parallel histopathological studies of the small intestine of irradiated rats through light microscopic showed significant decrease in the number of villi, villus height, mixed sub mucosa layer with more fibres and fibroblasts. Intestinal damage was in parallel to significant alterations of serum MAO activity, TBARS, 5-HT, DA, NE and EPI levels. Administration of curcumin before irradiation has significantly improved the levels of monoamines in small intestine and serum of irradiated rats, which was associated with significant amelioration in MAO activity and TBARS contents

The principal phenolic and alcoholic components of wine protect human lymphocytes against hydrogen peroxide- and ionising radiation-induced DNA damage in vitro

International Nuclear Information System (INIS)

Fenech, M.; Greenrod, W.

2003-01-01

We have tested the hypothesis that the alcoholic and phenolic components of wine are protective against the DNA damaging and cytotoxic effects of hydrogen peroxide and gamma radiation in vitro. The components of wine tested were ethanol, glycerol, a mixture of the phenolic compounds catechin and caffeic acid, and tartaric acid, all at concentrations that were 2.5% or 10.0% of the concentration in a typical Australian white wine Riesling. These components were tested individually or combined as a mixture and compared to a white wine stripped of polyphenols as well as a Hanks balanced salt solution control which was the diluent for the wine components. The effect of the components was tested in lymphocytes, using the cytokinesis-block micronucleus assay, after 30 minutes incubation in plasma or whole blood for the hydrogen peroxide or gamma-radiation challenge respectively. The results obtained showed that ethanol, glycerol, the catechin-caffeic acid mixture, the mixture of all components, and the stripped white wine significantly reduced the DNA damaging effects of hydrogen peroxide and gamma radiation (ANOVA P = 0.043 - 0.001). The strongest protective effect against DNA damage by gamma irradiation was observed for the catechin-caffeic acid mixture and mixture of all components (30% and 32% reduction respectively). These two treatments as well as ethanol produced the strongest protective effects against DNA damage by hydrogen peroxide (24%, 25% and 18% respectively) . The protection provided by the mixture did not account for the expected additive protective effects of the individual components suggesting that the components may be exerting their effects through similar mechanisms which are saturated at the concentrations tested. Ethanol was the only component that significantly increased base-line DNA damage rate, however, this effect was negated in the mixture. In conclusion our results suggest that the main phenolic and alcoholic components of wine can reduce

Early recognition of damage and course of damage on metal components

International Nuclear Information System (INIS)

1992-01-01

In 1985, the German Research Association set up the programme 'Early recognition of damage and course of damage on metal components'. The concept worked out by a programme committee provided that scientifically secured bases for the understanding of the occurrence of damage, the prevention of damage, affecting damage, and the mechanism triggering damage, or cumulation of damage should be obtained. 36 individual projects costing 14 million DM were supported in the course of 6 years. The task of a test group was to find these projects from a far larger number of applications which promised an increase in knowledge in the sense of the target of the programme. For the final colloquium, the test group chose those contributions which had not previously been published to the wider technical public. (orig.) [de

Protection of DPPC phospholipid liposomal membrane against radiation oxidative damage by antioxidants

Energy Technology Data Exchange (ETDEWEB)

Marathe, D.L.; Pandey, B.N.; Mishra, K.P [Bhabha Atomic Research Centre, Mumbai (India)

2000-05-01

Investigations in our laboratory on egg lecithin liposomes have recently showed a marked protection against damage by gamma radiation when cholesterol was present in the composition of vesicles suggesting a role of bilayer molecular architecture in the mechanism of free radical mediated lipid peroxidation. Present study was designed to determine the changes in bilayer permeability in DPPC unilamelar vesicles after exposure to gamma radiation by monitoring the leakage of pre-loaded carboxyfluorescein (CF), a marker loaded in aqueous interior of vesicle and fluidity alterations in the bilayer using fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH), a membrane bilayer probe. It was found that radiation doses of an order of magnitude higher were required to produce detectable changes in vesicles of DPPC than in the vesicles of egg lecithin suggesting a modulating role of chemical nature of composition in the membrane radiation sensitivity. It was significant to find that the leakage of CF from and incorporation of DPH into vesicle bilayer showed similar response pattern to radiation doses (0.1-6 kGy) which was also found to be dose rate dependent. Presence of antioxidants; alpha-tocopherol (0.15 mole %) in the bilayer membrane or ascorbic acid (0.1 mM) in the aqueous region significantly protected DPPC vesicles from radiation damage as determined from DPH uptake kinetics suggesting involvement of reactive free radicals of lipids as well as water radicals in the mechanism of membrane peroxidative damage. The magnitude of protection was found to increase with the increasing concentration of both these antioxidants but comparisons showed that {alpha}-tocopherol was far more effective in protecting the vesicles than ascorbic acid. These results contribute to our understanding of the mechanism of radiation oxidative damage and its modification by radical scavenging and/or organizational modulation which emphasize the importance of structure and composition of

Protection of DPPC phospholipid liposomal membrane against radiation oxidative damage by antioxidants

International Nuclear Information System (INIS)

Marathe, D.L.; Pandey, B.N.; Mishra, K.P

2000-01-01

Investigations in our laboratory on egg lecithin liposomes have recently showed a marked protection against damage by gamma radiation when cholesterol was present in the composition of vesicles suggesting a role of bilayer molecular architecture in the mechanism of free radical mediated lipid peroxidation. Present study was designed to determine the changes in bilayer permeability in DPPC unilamelar vesicles after exposure to gamma radiation by monitoring the leakage of pre-loaded carboxyfluorescein (CF), a marker loaded in aqueous interior of vesicle and fluidity alterations in the bilayer using fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH), a membrane bilayer probe. It was found that radiation doses of an order of magnitude higher were required to produce detectable changes in vesicles of DPPC than in the vesicles of egg lecithin suggesting a modulating role of chemical nature of composition in the membrane radiation sensitivity. It was significant to find that the leakage of CF from and incorporation of DPH into vesicle bilayer showed similar response pattern to radiation doses (0.1-6 kGy) which was also found to be dose rate dependent. Presence of antioxidants; alpha-tocopherol (0.15 mole %) in the bilayer membrane or ascorbic acid (0.1 mM) in the aqueous region significantly protected DPPC vesicles from radiation damage as determined from DPH uptake kinetics suggesting involvement of reactive free radicals of lipids as well as water radicals in the mechanism of membrane peroxidative damage. The magnitude of protection was found to increase with the increasing concentration of both these antioxidants but comparisons showed that α-tocopherol was far more effective in protecting the vesicles than ascorbic acid. These results contribute to our understanding of the mechanism of radiation oxidative damage and its modification by radical scavenging and/or organizational modulation which emphasize the importance of structure and composition of

High-Intensity Exercise Induced Oxidative Stress and Skeletal Muscle Damage in Postpubertal Boys and Girls: A Comparative Study.

Science.gov (United States)

Pal, Sangita; Chaki, Biswajit; Chattopadhyay, Sreya; Bandyopadhyay, Amit

2018-04-01

Pal, S, Chaki, B, Chattopadhyay, S, and Bandyopadhyay, A. High-intensity exercise induced oxidative stress and skeletal muscle damage in post-pubertal boys and girls: a comparative study. J Strength Cond Res 32(4): 1045-1052, 2018-The purpose of this study was to examine the sex variation in high-intensity exercise induced oxidative stress and muscle damage among 44 sedentary postpubertal boys and girls through estimation of postexercise release pattern of muscle damage markers like creatine kinase, lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and oxidative stress markers like extent of lipid peroxidation (thiobarbituric acid-reactive substances) and catalase activity. Muscle damage markers like creatine kinase, LDH, ALT, and AST were measured before, immediately after, and 24 and 48 hours after high-intensity incremental treadmill running. Oxidative stress markers like thiobarbituric acid-reactive substances and catalase activity were estimated before and immediately after the exercise. Lipid peroxidation and serum catalase activity increased significantly in both groups after exercise (p exercise level at 24 and 48 hours after exercise in both the sexes, (p exercise, the pattern of postexercise release of these markers were found to be similar in both the groups. Accordingly, it has been concluded from the present investigation that high-intensity exercise induces significant oxidative stress and increases indices of skeletal muscle damage in both postpubertal girls and boys. However, postpubertal girls are relatively better protected from oxidative stress and muscle damage as compared to the boys of similar age and physical activity level. It is further evident that sex difference may not be apparent for all the biomarkers of muscle damage in this age group.