Biological Damage

The overall aim of this study is to determine the most effective way to reduce the radiation dose to the breast during non-breast related CT scans, whilst still maintaining a suitable image quality. This study will attempt to compare the doses and noise of various protocols that can be used for dose reduction, including tube current modulation, bismuth breast shields and manual reduction of tube current.

111p runthenight07 01-03-2023 10 3   Download

Autophagy and DNA repair are two essential biological mechanisms that maintain cellular homeostasis. Impairment of these mechanisms was associated with several pathologies such as premature aging, neurodegenerative diseases, and cancer. Intrinsic or extrinsic stress stimuli (e.g., reactive oxygen species or ionizing radiation) cause DNA damage. As a biological stress response, autophagy is activated following insults that threaten DNA integrity.

18p thiencuuchu 27-11-2021 11 1   Download

Among various pests, the brown planthopper (BPH) that damages rice is the major destructive pests. Understanding resistance mechanisms is a critical step toward effective control of BPH.

11p vishikamaru2711 29-04-2020 10 0   Download

Objectives of the thesis: Identifying the Meloidogyne species causing damage on main crops in Tay Nguyen Highlands. Analyze the diversity of Meloidogyne species based on morphology and molecular classification. Assessing the preventative ability of antagonistic microorganisms to Meloidogyne incognita in laboratory condition.

27p xacxuoc4321 08-07-2019 35 5   Download

The objectives of the thesis: To identify species composition of PPNs on carrots in major carrot growing areas in Vietnam. To determine the parasitic nematode group causing significant damage to carrots in the studied areas. To evaluate the ability to control some important PPNs on carrots by using antagonistic fungi in the laboratory conditions.

27p xacxuoc4321 09-07-2019 61 4   Download

Theoxidation-promotingreactivityof copper(II) complexof aminoglycosidic antibiotic amikacin [Cu(II)-Ami] in the presence of hydrogen peroxide, was studied at pH 7.4, using 2¢-deoxyguanosine (dG), pBR322 plasmid DNA and yeast tRNA Phe as target molecules. Themixtures of complexwith H2O2were found to be efficient oxidants, converting dG to its 8-oxo derivative, generating strand breaks in plasmid DNA and multiple cleavages in tRNA Phe .

10p tumor12 22-04-2013 35 3   Download

The 90-kDa heat shock protein (Hsp90) is a molecular chaperone that assists both in ATP-independent sequestra-tion of damaged proteins, and inATP-dependent folding of numerous targets, such as nuclear hormone receptors and protein kinases. Recent work from our lab and others has established the existence of a second, C-terminal nucleotide bindingsite besides the well characterized N-terminal, gel-danamycin-sensitive ATP-bindingsite.

8p fptmusic 16-04-2013 33 4   Download

The herpes simplex virus thymidine kinase⁄ganciclovir (HSV-tk⁄GCV) sys-tem that selectively depletes cells expressing HSV-tk upon treatment with GCV has provided a valuable tool for developing a new animal model expressing the desired tissue damage. In this paper, an HSV-tk vector with an albumin promoter⁄enhancer was constructed. Based on the favourable killing effect on Hep-G2 cells by the recombinant construct, the HSV-tk transgenic mouse strains were developed.

9p awards 06-04-2013 53 3   Download

Enzyme catalysis in low water containing organic solvents is finding an increasing number of applications in diverse areas.This review focuses on some aspects which have not been reviewed elsewhere.Different strategies for obtaining higher activity and stability in such media are described.In this context, the damaging role of lyophilization and the means of overcoming such effects are discussed.Ultrasoni-cation and microwave assistance are two emerging approa-ches for enhancing reaction rates in low water media.

9p dell39 03-04-2013 62 4   Download

Stress protein responses have evolved in part as a mechanism to protect cells from the toxic effects of environmental damaging agents. Oesophageal squamous epithelial cells have evolved an atypical stress response that results in the synthesis of a 53 kDa protein of undefined function named squamous epithelial-induced stress protein of 53 kDa (SEP53).

18p inspiron33 26-03-2013 59 5   Download

We investigated the survival signals of epidermal growth factor (EGF) in human gastric adenocarcinoma cell line TMK-1. Treatment of TMK-1 cells with adriamycin (ADR) caused apoptosis and apoptosis-related reactions such as the release of cytochromecfrom mitochondria and the activation of caspase 9.

13p inspiron33 25-03-2013 42 2   Download

Adenosylcobalamin-dependent diol and glycerol dehydratases are isofunc-tional enzymes and undergo mechanism-based inactivation by a physiologi-cal substrate glycerol during catalysis. Inactivated holoenzymes are reactivated by their own reactivating factors that mediate the ATP-depen-dent exchange of an enzyme-bound, damaged cofactor for free adenosylco-balamin through intermediary formation of apoenzyme.

11p media19 04-03-2013 36 2   Download

Human 8-oxoguanine-DNA glycosylase (OGG1) efficiently removes muta-genic 8-oxo-7,8-dihydroguanine (8-oxoGua) and 2,6-diamino-4-hydroxy-5-formamidopyrimidine when paired with cytosine in oxidatively damaged DNA. Excision of 8-oxoGua mispaired with adenine may lead to GfiT transversions.

14p vinaphone15 25-02-2013 41 3   Download

Motor neuron degeneration in amyotrophic lateral sclerosis involves oxida-tive damage. Glutathione (GSH) is critical as an antioxidant and a redox modulator. We used a motor neuronal cell line (NSC-34) to investigate whether wild-type and familial amyotrophic lateral sclerosis-linked G93A mutant Cu,Zn superoxide dismutase (wt⁄G93ASOD1) modified the GSH pool and glutamate cysteine ligase (GCL), the rate-limiting enzyme for GSH synthesis.

14p viettel02 22-02-2013 25 3   Download

Cockayne syndrome (CS) is a complex, progressive disease that involves neurological and developmental impairment and premature aging. The majority of CS patients have mutations in theCSBgene. The CSB protein is involved in multiple DNA repair pathways and CSBmutated cells are sensitive to a broad spectrum of genotoxic agents.

11p viettel02 22-02-2013 32 4   Download

Antimicrobial peptides participate in innate host defense by directly elimi-nating pathogens as a result of their ability to damage the microbial mem-brane and by providing danger signals that will recruit innate immune cells to the site of infection. Dermaseptin DA4 (DRS-DA4), a new antimicrobial peptide of the dermaseptin superfamily, was identified based on its chemo-tactic properties, contrasting with the currently used microbicidal proper-ties assessment.

14p viettel02 20-02-2013 37 3   Download

he tumor suppressor, breast cancer susceptibility gene 1 (BRCA1), plays an integral role in the maintenance of genome stability and, in particular, the cellular response to DNA damage. Here, the emerging role of BRCA1 in nonhomologous end-joining-mediated DNA repair following DNA dam-age will be reviewed, as well as the activation of apoptotic pathways.

7p viettel02 19-02-2013 49 3   Download

Thymoquinone, a naturally derived agent, has been shown to possess anti-oxidant, antiproliferative and proapoptotic activities. In the present study, we explored thymoquinone effects on the proteasomal complex, the major system involved in the removal of damaged, oxidized and misfolded pro-teins.

14p mobifone23 21-01-2013 39 4   Download

The ubiquinone coenzyme Q (CoQ) is synthesized in mitochondria with a large, hydrophobic isoprenoid side chain. It functions in mitochondrial res-piration as well as protecting membranes from oxidative damage. Yeast that cannot synthesize CoQ (DCoQ) are viable, but cannot grow on nonfer-mentable carbon sources, unless supplied with ubiquinone.

16p mobifone23 21-01-2013 24 4   Download

Oxidative damage to mtDNA is associated with excessive reactive oxygen species production. The mitochondrial common deletion (mtDNA 4977-bp and 4834-bp deletion in humans and rats, respectively) is the most typical and frequent form of mtDNA damage associated with aging and degenera-tive diseases.

11p cosis54 05-01-2013 41 5   Download