• Title/Summary/Keyword: Chain initiation

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Roles of Oxidative Stress in the Development and Progression of Breast Cancer

  • Nourazarian, Ali Reza;Kangari, Parisa;Salmaninejad, Arash
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.12
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    • pp.4745-4751
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    • 2014
  • Oxidative stress is caused by an imbalance in the redox status of the body. In such a state, increase of free radicals in the body can lead to tissue damage. One of the most important species of free radicals is reactive oxygen species (ROS) produced by various metabolic pathways, including aerobic metabolism in the mitochondrial respiratory chain. It plays a critical role in the initiation and progression of various types of cancers. ROS affects different signaling pathways, including growth factors and mitogenic pathways, and controls many cellular processes, including cell proliferation, and thus stimulates the uncontrolled growth of cells which encourages the development of tumors and begins the process of carcinogenesis. Increased oxidative stress caused by reactive species can reduce the body's antioxidant defense against angiogenesis and metastasis in cancer cells. These processes are main factors in the development of cancer. Bimolecular reactions cause free radicals in which create such compounds as malondialdehyde (MDA) and hydroxyguanosine. These substances can be used as indicators of cancer. In this review, free radicals as oxidizing agents, antioxidants as the immune system, and the role of oxidative stress in cancer, particularly breast cancer, have been investigated in the hope that better identification of the factors involved in the occurrence and spread of cancer will improve the identification of treatment goals.

Role of Osmotic and Salt Stress in the Expression of Erythrose Reductase in Candida magnoliae

  • Park, Eun-Hee;Lee, Ha-Yeon;Ryu, Yeon-Woo;Seo, Jin-Ho;Kim, Myoung-Dong
    • Journal of Microbiology and Biotechnology
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    • v.21 no.10
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    • pp.1064-1068
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    • 2011
  • The osmotolerant yeast, Candida magnoliae, which was isolated from honeycomb, produces erythritol from sugars such as fructose, glucose, and sucrose. Erythrose reductase in C. magnoliae (CmER) reduces erythrose to erythritol with concomitant oxidation of NAD(P)H. Sequence analysis of the 5'-flanking region of the CmER gene indicated that one putative stress response element (STRE, 5'-AGGGG-3'), found in Saccharomyces cerevisiae, exists 72 nucleotides upstream of the translation initiation codon. An enzyme activity assay and semiquantitative reverse transcription polymerase chain reaction revealed that the expression of CmER is upregulated under osmotic and salt stress conditions caused by a high concentration of sugar, KCl, and NaCl. However, CmER was not affected by osmotic and oxidative stress induced by sorbitol and $H_2O_2$, respectively. The basal transcript level of CmER in the presence of sucrose was higher than that in cells treated with fructose and glucose, indicating that the response of CmER to sugar stress is different from that of GRE3 in S. cerevisiae, which expresses aldose reductase in a sugarindependent manner. It was concluded that regulation of CmER differs from that of other aldose reductases in S. cerevisiae.

Effect of Time of Initiating Dietary Fat Supplementation on Performance and Reproduction of Early Lactation Dairy Cows

  • Son, J.;Larson, L.L.;Grant, R.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.2
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    • pp.182-187
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    • 2000
  • Forty-two Holstein cows (21 multiparous) were assigned by calving date and parity to three dietary sequences to evaluate the effect of time of initiating fat supplementation to diets on lactation and reproductive performance. The dietary sequences were: 1) control, no supplemental fat from 1 to 98 days in milk (DIM) ; 2) control diet from 1 to 28 DIM then 3% supplemental fat (calcium salts of long-chain fatty acids) from 29 to 98 DIM; or 3) 3% supplemental fat from 1 to 98 DIM. Feeding supplemental fat did not enhance mean milk and 4% fat corrected milk (FCM) yields, but efficiency of FCM production was higher for cows fed supplemental fat. Milk fat percentage was unchanged whereas milk protein percentage was depressed with fat supplementation. Feeding supplemental fat reduced DMI and energy balance but there were no differences among treatments on time to resumption of ovarian cyclicity or conception rate to first service. Concentrations of progesterone during the first two ovulatory cycles tended to be greater in the fat-supplemented groups. Feeding supplemental fat starting at either parturition or 29 DIM increased efficiency of FCM production, but did not greatly enhance reproductive performance.

Autophagy in Cervical Cancer: An Emerging Therapeutic Target

  • Pandey, Saumya;Chandravati, Chandravati
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.10
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    • pp.4867-4871
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    • 2012
  • Cervical cancer is a leading cause of morbidity and mortality in women worldwide. Although the human papillomavirus (HPV) is considered the major causative agent of cervical cancer, yet the viral infection alone is not sufficient for cancer progression. The etiopathogenesis of cervical cancer is indeed complex; a precise understanding of the complex cellular/molecular mechanisms underlying the initiation, progression and/or prevention of the uterine cervix is therefore essential. Autophagy is emerging as an important biological mechanism in targeting human cancers, including cervical cancer. Furthermore, autophagy, a process of cytoplasm and cellular organelle degradation in lysosomes, has been implicated in homeostasis. Autophagic flux may vary depending on the cell/tissue type, thereby altering cell fate under stress conditions leading to cell survival and/or cell death. Autophagy may in turn govern tumor metastasis and subsequent carcinogenesis. Inflammation is a known hallmark of cancer. Vascular insufficiency in tumors, including cervical tissue, leads to depletion of glucose and/or oxygen perturbing the osmotic mileu causing extracellular acidosis in the tumor microenvironment that may eventually result in autophagy. Thus, targeted manipulation of complex autophagic signaling may prove to be an innovative strategy in identification of clinically relevant biomarkers in cervical cancer in the near future.

The Oxidative Modification of COL6A1 in Membrane Proteins of Ovarian Cancer Patients

  • Yang, Hee-Young;Lee, Tae-Hoon
    • Reproductive and Developmental Biology
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    • v.36 no.1
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    • pp.39-47
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    • 2012
  • Ovarian cancer is the most lethal gynecological malignancy, and specific biomarkers are important needed to improve diagnosis, prognosis, and to forecast and monitor treatment efficiency. There are a lot of pathological factors, including reactive oxygen species (ROS), involved in the process of cancer initiation and progression. The oxidative modification of proteins by ROS is implicated in the etiology or progression of disorders and diseases. In this study, a labeling experiment with the thiol-modifying reagent biotinylated iodoacetamide (BIAM) revealed that a variety of proteins were differentially oxidized between normal and tumor tissues of ovarian cancer patients. To identify cysteine oxidation-sensitive proteins in ovarian cancer patients, we performed comparative analysis by nano-UPLC-$MS^E$ shotgun proteomics. We found oxidation-sensitive 22 proteins from 41 peptides containing cysteine oxidation. Using Ingenuity program, these proteins identified were established with canonical network related to cytoskeletal network, cellular organization and maintenance, and metabolism. Among oxidation-sensitive proteins, the modification pattern of Collagen alpha-1(VI) chain (COL6A1) was firstly confirmed between normal and tumor tissues of patients by 2-DE western blotting. This result suggested that COL6A1 might have cysteine oxidative modification in tumor tissue of ovarian cancer patients.

Ecological Risk Assessment of Chemicals of Concern for Initiation of Ecorisk-based Water Quality Standards in Korea (생태수질기준설정을 위한 대상물질의 생태위해성 평가)

  • An, Youn-Joo;Nam, Sun-Hwa;Kim, Yong-Hwa
    • Journal of Korean Society on Water Environment
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    • v.24 no.5
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    • pp.592-597
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    • 2008
  • Current water quality standard (WQS) in Korea is based on the protection of human health, not considering the protection of aquatic organisms. Most of chemicals can be toxic to ecological biota as well as human. Health of aquatic biota is closely related to the human health via food chain, therefore ecological risk based-WQS needs to be developed to protect the aquatic ecosystem. In this study, we selected the 31 chemicals in the Project entitled 'Development of integrated methodology for evaluation of water environment'. The methodology for calculating water quality criteria was derived from the Australian and New Zealand processes for deriving guideline trigger value for aquatic ecosystem. The available ecotoxicity data were collected from US EPA's ECOTOXicology Database (ECOTOX), TOX-2000 Database, European Chemicals Bureau (ECB)'s International Uniform Chemical Information Database (IUCLID) and Environmental Protection Agency (US EPA)'s report 'Ambient Water Quality Criteria (AWQC)'. The aquatic toxicity data for the Korean species were selected for risk assessment to reflect the Korean water environment. The monitoring values were calculated from the water quality monitoring data four main Korean rivers. We suggested the order of priorities of chemicals based on ecological risk assessment. We expect that these results can be useful information for establishing the WQS for the protection of aquatic ecosystem.

Different Protein Expression between Human Eosinophilic Leukemia Cells, EoL-1 and Imatinib-resistant EoL-1 Cells, EoL-1-IR

  • Sung, Kee-Hyung;Kim, In-Sik;Lee, Ji-Sook
    • Biomedical Science Letters
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    • v.24 no.4
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    • pp.426-429
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    • 2018
  • Chronic eosinophilic leukemia (CEL) is characterized by eosinophilia and organ damage. Imatinib is widely used for treating CEL, chronic myeloid leukemia (CML) and acute myeloid leukemia (AML). Unfortunately, the cancer cells gain resistance against the drug after prolonged molecular-targeted therapies. Imatinib-resistant EoL-1 (EoL-1-IR) cells were produced from chronic eosinophilic leukemia cells (EoL-1) after treatment with imatinib for a long duration. Two-dimensional electrophoresis (2-DE) analysis revealed numerous protein variations in the EoL-1 and EoL-1-IR sub-types. Compared to the EoL-1 cells, expression levels of TIP49, RBBP7, ${\alpha}$-enolase, adenosine deaminase, C protein, galactokinase, eukaryotic translation initiation factor, $IFN-{\gamma}$, and human protein homologous to DROER were increased, whereas core I protein, proteasome subunit p42, heterogeneous ribonuclear particle protein, chain B, and nucleoside diphosphate were decreased in the EoL-1-IR cells. Taken together, these results contribute to understanding the pathogenic mechanism of drug-resistant diseases.

Circulating HOTAIR LncRNA Is Potentially Up-regulated in Coronary Artery Disease

  • Avazpour, Niloofar;Hajjari, Mohammadreza;Yazdankhah, Saeed;Sahni, Azita;Foroughmand, Ali Mohammad
    • Genomics & Informatics
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    • v.16 no.4
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    • pp.25.1-25.5
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    • 2018
  • Coronary artery disease (CAD) is one of the leading causes of death and disability all around the world. Recent studies have revealed that aberrantly regulated long non-coding RNA (lncRNA) as one of the main classes of cellular transcript plays a key regulatory role in transcriptional and epigenetic pathways. Recent reports have demonstrated that circulating lncRNAs in the blood can be potential biomarkers for CAD. HOTAIR is one of the most cited lncRNAs with a critical role in the initiation and progression of the gene expression regulation. Recent research on the role of the HOTAIR in cardiovascular disease lays the basis for the development of new studies considering this lncRNA as a potential biomarker and therapeutic target in CAD. In this study, we aimed to compare the expression of HOTAIR lncRNA in the blood samples of patients with CAD and control samples. The expression level was examined by semi-quantitative reverse transcriptase polymerase chain reaction technique. Our data shows that expression of HOTAIR is up-regulated in blood samples of patients with CAD.

Increasing of Macrophage Migration Inhibitory Factor Expression in Human Patients Infected with Virulent Brucella in Iraq

  • Khudhur, Hasan R.;Menshed, Abbas Ali;Hasan, Ahmed Abbas
    • Microbiology and Biotechnology Letters
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    • v.48 no.4
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    • pp.569-573
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    • 2020
  • Brucellosis is a zoonotic disease caused by Brucella infections and humans usually contract this disease from close contact with infected animals or their products, usually via the ingestion of cheese or crude milk. Macrophage migration inhibitory factor (MIF) and Pro- and anti-inflammatory cytokines play an important role in susceptibility/resistance and the immunopathogenesis of Brucella infection. These cytokines are crucial factors in the initiation and progression of protective immunity against Brucella infection but the role of MIF has not been well studied in the human response to intracellular microbes. This study was designed to investigate the effect of MIF expression on Brucella susceptibility. A total of 85 positive rose Bengal tests and 24 samples from healthy individuals were collected for this study and subjected to polymerase chain reaction assays (PCR) of the bcsp31 diagnostic gene. MIF concentrations were evaluated using Enzyme-Linked immunosorbent assay (ELISA) and the results showed that 46 (54%) of the rose Bengal test samples were positive and 39 (46%) were negative for bcsp31 (p ≤ 0.05) and used as the gold standard for all of the comparisons in this study. The ELISA results indicate that the mean concentration of MIF was significantly higher in patients with positive rose Bengal tests when compared to the control groups and that its concentration increases with increasing age in both the patient and control groups (p ≤ 0.05).

Composite components damage tracking and dynamic structural behaviour with AI algorithm

  • Chen, Z.Y.;Peng, Sheng-Hsiang;Meng, Yahui;Wang, Ruei-Yuan;Fu, Qiuli;Chen, Timothy
    • Steel and Composite Structures
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    • v.42 no.2
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    • pp.151-159
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    • 2022
  • This study discusses a hypothetical method for tracking the propagation damage of Carbon Reinforced Fiber Plastic (CRFP) components underneath vibration fatigue. The High Cycle Fatigue (HCF) behavior of composite materials was generally not as severe as this of admixture alloys. Each fissure initiation in metal alloys may quickly lead to the opposite. The HCF behavior of composite materials is usually an extended state of continuous degradation between resin and fibers. The increase is that any layer-to-layer contact conditions during delamination opening will cause a dynamic complex response, which may be non-linear and dependent on temperature. Usually resulted from major deformations, it could be properly surveyed by a non-contact investigation system. Here, this article discusses the scanning laser application of that vibrometer to track the propagation damage of CRFP components underneath fatigue vibration loading. Thus, the study purpose is to demonstrate that the investigation method can implement systematically a series of hypothetical means and dynamic characteristics. The application of the relaxation method based on numerical simulation in the Artificial Intelligence (AI) Evolved Bat (EB) strategy to reduce the dynamic response is proved by numerical simulation. Thermal imaging cameras are also measurement parts of the chain and provide information in qualitative about the temperature location of the evolution and hot spots of damage.