ASSESSMENT OF THE RISK OF SOLAR ULTRAVIOLET RADIATION TO AMPHIBIANS. 1) DOSE-DEPENDENT INDUCTION OF HINDLIMB MALFORMATIONS IN THE NORTHERN LEOPARD FROG (RANA PIPIENS)

EPA Science Inventory

A number of environmental stressors have been hypothesized as responsible for seeming increases in limb malformations in several species of North American amphibians. The purpose of this study was to generate dose-response data suitable for assessing the potential role of solar u...

CYTOCHROMES P450 (CYP) IN THE POECILIOPSIS LUCIDA HEPATOCELLULAR CARCINOMA CELL LINE (PLHC-1): DOSE- AND TIME-DEPENDENT GLUCOCORTICOID POTENTIATION OF CYP1A INDUCTION WITHOUT INDUCTION OF CYP3A. (R823889)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Tumor induction in mice after local irradiation with single doses of either carbon-ion beams or gamma rays.

PubMed

Ando, Koichi; Koike, Sachiko; Ohmachi, Yasushi; Ando, Yutaka; Kobashi, Gen

2014-12-01

To determine the dose-dependent relative biological effectiveness (RBE) for tumor prevalence in mice receiving single localized doses to their right leg of either carbon ions (15, 45 or 75 keV/μm) or 137Cs gamma rays. A total of 1647 female C3H mice were irradiated to their hind legs with a localized dose of either reference gamma rays or 15, 45 or 75 keV/μm carbon-ion beams. Irradiated mice were evaluated for tumors twice a month during their three-year life span, and the dimensions of any tumors found were measured with a caliper. The tumor induction frequency was calculated by Kaplan-Meier analysis. The incidence of tumors from 50 Gy of 45 keV/μm carbon ions was marginally higher than those from 50 Gy of gamma rays. However, 60 Gy of 15 keV/μm carbon ions induced significantly fewer tumors than did gamma rays. RBE values of 0.87 + 0.12, 1.29 + 0.08 or 2.06 + 0.39 for lifetime tumorigenesis were calculated for 15, 45 or 75 keV/μm carbon-ion beams, respectively. Fibrosarcoma predominated, with no Linear Energy Transfer (LET)-dependent differences in the tumor histology. Experiments measuring the late effect of leg skin shrinkage suggested that the carcinogenic damage of 15 keV/μm carbon ions would be less than that of gamma rays. We conclude that patients receiving radiation doses to their normal tissues would face less risk of secondary tumor induction by carbon ions of intermediate LET values compared to equivalent doses of photons.

Long-Acting Injectable Naltrexone Induction: A Randomized Trial of Outpatient Opioid Detoxification With Naltrexone Versus Buprenorphine.

PubMed

Sullivan, Maria; Bisaga, Adam; Pavlicova, Martina; Choi, C Jean; Mishlen, Kaitlyn; Carpenter, Kenneth M; Levin, Frances R; Dakwar, Elias; Mariani, John J; Nunes, Edward V

2017-05-01

At present there is no established optimal approach for transitioning opioid-dependent adults to extended-release injection naltrexone (XR-naltrexone) while preventing relapse. The authors conducted a trial examining the efficacy of two methods of outpatient opioid detoxification for induction to XR-naltrexone. Participants were 150 opioid-dependent adults randomly assigned 2:1 to one of two outpatient detoxification regimens, naltrexone-assisted detoxification or buprenorphine-assisted detoxification, followed by an injection of XR-naltrexone. Naltrexone-assisted detoxification lasted 7 days and included a single day of buprenorphine followed by ascending doses of oral naltrexone along with clonidine and other adjunctive medications. Buprenorphine-assisted detoxification included a 7-day buprenorphine taper followed by a week-long delay before administration of XR-naltrexone, consistent with official prescribing information for XR-naltrexone. Participants from both groups received behavioral therapy focused on medication adherence and a second dose of XR-naltrexone. Compared with participants in the buprenorphine-assisted detoxification condition, participants assigned to naltrexone-assisted detoxification were significantly more likely to be successfully inducted to XR-naltrexone (56.1% compared with 32.7%) and to receive the second injection at week 5 (50.0% compared with 26.9%). Both models adjusted for primary type of opioid use, route of opioid administration, and morphine equivalents at baseline. These results demonstrate the safety, efficacy, and tolerability of low-dose naltrexone, in conjunction with single-day buprenorphine dosing and adjunctive nonopioid medications, for initiating adults with opioid dependence to XR-naltrexone. This strategy offers a promising alternative to the high rates of attrition and relapse currently observed with agonist tapers in both inpatient and outpatient settings.

Induction and quantification of gammma-H2AX foci following cx- and gamma-irradiaton

NASA Technical Reports Server (NTRS)

Leatherbarrow, E. L.; Cucinotta, F. A.; O'Neill, Peter

2004-01-01

Following DNA damage the histone H2AX becomes phosphorylated and can be visualised by immunofluorescence as an indicator of DSBs in individual cells. Using a wild type hamster cell line (V79-4) exposed to either a-particles or to Co-60 gamma-rays to induce DNA DSBs at different doses (20-200OmGy), the dose dependent induction of gamma-H2AX foci were scored both manually (by eye) and using image analysis. A linearly dependence on dose was found for both radiations. The number of DSBs determined by image analysis after a post-irradiation period of 30 minutes at 37 C, is 16.6 foci/cell/Gy for alpha-irradiation and 12.2 foci/cell/Gy for gamma-irradiation; the latter being 3-4 times the levels observed by eye and comparable to gamma-radiation-induced levels of prompt DSBs more recently reported using pulse field gel electrophoresis (approx. 16 DSBs/Gy). The average size of the gamma-H2AX foci induced by alpha-irradiation (0.30 square micrometers) is approximately 1.5 times larger than those induced by gamma-irradiation (0.19 square micrometers). The timescale of induction and removal of DSBs up to 24 hours post-irradiation, was investigated with gamma-H2AX foci levels found to remain significantly higher than controls for 4 or 6 hours in gamma-irradiated samples or alpha irradiated samples, respectively. These results demonstrate that not only gamma radiation but also alpha-radiation induce phosphorylation of the H2AX histone in response to DSBs even at low doses (20mGy for gamma-rays, 1 track/cell on average for alpha-particles) and the variation in size and dephosphorylation of the induced foci is dependent on radiation quality (LET).

The c-Abl signaling network in the radioadaptive response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chi-Min, Yuan

2014-01-28

The radioadaptive response, or radiation hormesis, i.e. a low dose of radiation can protect cells and organisms from the effects of a subsequent higher dose, is a widely recognized phenomenon. Mechanisms underlying such radiation hormesis, however, remain largely unclear. Preliminary studies indicate an important role of c-Abl signaling in mediating the radioadaptive response. We propose to investigate how c-Abl regulates the crosstalk between p53 and NFκB in response to low doses irradiation. We found in our recent study that low dose IR induces a reciprocal p53 suppression and NFκB activation, which induces HIF-a and subsequently a metabolic reprogramming resulting inmore » a transition from oxidative phosphorylation to glycolysis. Of importance is that this glycolytic switch is essential for the radioadaptive response. This low-dose radiationinduced HIF1α activation was in sharp contrast with the high-dose IR-induced p53 activation and HIF1α inhibition. HIF1α and p53 seem to play distinct roles in mediating the radiation dose-dependent metabolic response. The induction of HIF1α-mediated glycolysis is restricted to a low dose range of radiation, which may have important implications in assessing the level of radiation exposure and its potential health risk. Our results support a dose-dependent metabolic response to IR. When IR doses are below the threshold of causing detectable DNA damage (<0.2Gy) and thus little p53 activation, HIF1α is induced resulting in induction of glycolysis and increased radiation resistance. When the radiation dose reaches levels eliciting DNA damage, p53 is activated and diminishes the activity of HIF1α and glycolysis, leading to the induction of cell death. Our work challenges the LNT model of radiation exposure risk and provides a metabolic mechanism of radioadaptive response. The study supports a need for determining the p53 and HIF1α activity as a potential reliable biological readout of radiation exposure in humans. The exquisite sensitivity of cellular metabolism to low doses of radiation could also serve as a valuable biomarker for estimating the health effects of low-level radiation exposure.« less

INDUCTION AND SUPPRESSION OF CYTOCHROME P450 1A BY 3,3', 4,4', 5-PENTACHLOROBIPHENYL AND ITS RELATIONSHIP TO OXIDATIVE STRESS IN THE MARINE FISH SCUP (STENOTOMUS CHRYSOPS). (R827102)

EPA Science Inventory

Abstract

The planar polychlorinated biphenyl (PCB) 3,3',4,4'-tetrachlorobiphenyl (TCB) causes dose-dependent induction and post-transcriptional suppression of hepatic cytochrome P450 1A (CYP1A) in the marine teleost scup (Stenotomus chrysops). That suppr...

Induction of apoptosis in human promyelocytic leukemia HL-60 cells by Ampelopsis cantoniensis crude extract.

PubMed

Tan, Tzu-Wei; Tsai, Huei-Yann; Chen, Yuh-Fung; Chung, Jing-Gung

2004-01-01

The crude extract of Ampelopsis cantoniensis induced apoptosis in human promyelocytic leukemia HL-60 cells and this induction was investigated by flow cytometric analysis, DNA gel electrophoresis and poly (ADP-ribose) fluorescence staining. The results demonstrated that this extract induced dose-dependent cytotoxicity and apoptosis. The level of active caspase-3 was increased after treatment with the crude extract for 24 hours.

Analysis of mutagenic DNA repair in a thermoconditional mutant of Saccharomyces cerevisiae. III. Dose-response pattern of mutation induction in UV-irradiated rev2ts cells.

PubMed

Siede, W; Eckardt, F

1986-01-01

Recent studies regarding the influence of cycloheximide on the temperature-dependent increase in survival and mutation frequencies of a thermoconditional rev2 mutant lead to the suggestion that the REV2-coded mutagenic repair function is UV-inducible. In the present study we show that stationary-phase rev2ts cells are characterized by a biphasic linear-quadratic dose-dependence of mutation induction ("mutation kinetics") of ochre alleles at 23 degrees C (permissive temperature) but linear kinetics at the restrictive temperature of 36 degrees C. Mathematical analysis using a model based on Poisson statistics and a further mathematical procedure, the calculation of "apparent survival", support the assumption that the quadratic component of the reverse mutation kinetics investigated can be attributed to a UV-inducible component of mutagenic DNA repair controlled by the REV2 gene.

Induction of P450 genes in Nilaparvata lugens and Sogatella furcifera by two neonicotinoid insecticides.

PubMed

Yang, Yuan-Xue; Yu, Na; Zhang, Jian-Hua; Zhang, Yi-Xi; Liu, Ze-Wen

2018-06-01

Nilaparvata lugens and Sogatella furcifera are two primary planthoppers on rice throughout Asian countries and areas. Neonicotinoid insecticides, such as imidacloprid (IMI), have been extensively used to control rice planthoppers and IMI resistance consequently occurred with an important mechanism from the over-expression of P450 genes. The induction of P450 genes by IMI may increase the ability to metabolize this insecticide in planthoppers and increase the resistance risk. In this study, the induction of P450 genes was compared in S. furcifera treated with IMI and nitromethyleneimidazole (NMI), in two planthopper species by IMI lethal dose that kills 85% of the population (LD 85 ), and in N. lugens among three IMI doses (LD 15 , LD 50 and LD 85 ). When IMI and NMI at the LD 85 dose were applied to S. furcifera, the expression changes in most P450 genes were similar, including the up-regulation of nine genes and down-regulation of three genes. In terms of the expression changes in 12 homologous P450 genes between N. lugens and S. furcifera treated with IMI at the LD 85 dose, 10 genes had very similar patterns, such as up-regulation in seven genes, down-regulation in one gene and no significant changes in two genes. When three different IMI doses were applied to N. lugens, the changes in P450 gene expression were much different, such as up-regulation in four genes at all doses and dose-dependent regulation of the other nine genes. For example, CYP6AY1 could be induced by all IMI doses, while CYP6ER1 was only up-regulated by the LD 50 dose, although both genes were reported important in IMI resistance. In conclusion, P450 genes in two planthopper species showed similar regulation patterns in responding to IMI, and the two neonicotinoid insecticides had similar effects on P450 gene expression, although the regulation was often dose-dependent. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Quantitative prediction of repaglinide-rifampicin complex drug interactions using dynamic and static mechanistic models: delineating differential CYP3A4 induction and OATP1B1 inhibition potential of rifampicin.

PubMed

Varma, Manthena V S; Lin, Jian; Bi, Yi-An; Rotter, Charles J; Fahmi, Odette A; Lam, Justine L; El-Kattan, Ayman F; Goosen, Theunis C; Lai, Yurong

2013-05-01

Repaglinide is mainly metabolized by cytochrome P450 enzymes CYP2C8 and CYP3A4, and it is also a substrate to a hepatic uptake transporter, organic anion transporting polypeptide (OATP)1B1. The purpose of this study is to predict the dosing time-dependent pharmacokinetic interactions of repaglinide with rifampicin, using mechanistic models. In vitro hepatic transport of repaglinide, characterized using sandwich-cultured human hepatocytes, and intrinsic metabolic parameters were used to build a dynamic whole-body physiologically-based pharmacokinetic (PBPK) model. The PBPK model adequately described repaglinide plasma concentration-time profiles and successfully predicted area under the plasma concentration-time curve ratios of repaglinide (within ± 25% error), dosed (staggered 0-24 hours) after rifampicin treatment when primarily considering induction of CYP3A4 and reversible inhibition of OATP1B1 by rifampicin. Further, a static mechanistic "extended net-effect" model incorporating transport and metabolic disposition parameters of repaglinide and interaction potency of rifampicin was devised. Predictions based on the static model are similar to those observed in the clinic (average error ∼19%) and to those based on the PBPK model. Both the models suggested that the combined effect of increased gut extraction and decreased hepatic uptake caused minimal repaglinide systemic exposure change when repaglinide is dosed simultaneously or 1 hour after the rifampicin dose. On the other hand, isolated induction effect as a result of temporal separation of the two drugs translated to an approximate 5-fold reduction in repaglinide systemic exposure. In conclusion, both dynamic and static mechanistic models are instrumental in delineating the quantitative contribution of transport and metabolism in the dosing time-dependent repaglinide-rifampicin interactions.

Benzo(a)pyrene-induced cytochrome p4501A expression of four freshwater fishes (Oryzias latipes, Danio rerio, Cyprinus carpio, and Zacco platypus).

PubMed

Lee, Jin Wuk; Yoon, Hong-Gil; Lee, Sung Kyu

2015-05-01

Oryzias latipes, Danio rerio, Cyprinus carpio, and Zacco platypus are useful indicator species for CYP1A biomarker studies; however, comparative studies have not been performed. To compare susceptibility, dose- and time-dependent CYP1A induction at the mRNA and protein levels in response to benzo(a)pyrene (BaP) exposure was analyzed. At the mRNA level, a statistically significant difference was found among the four species; however, such was not observed at the protein level. C. carpio showed the highest CYP1A induction level and the steepest slope in the dose-response curve. To assess susceptibility, the difference in CYP1A mRNA induction among species must be considered, and C. carpio was the most sensitive species of the four evaluated in terms of CYP1A expression. Copyright © 2015 Elsevier B.V. All rights reserved.

Formononetin suppresses the proliferation of human non-small cell lung cancer through induction of cell cycle arrest and apoptosis.

PubMed

Yang, Yi; Zhao, Yi; Ai, Xinghao; Cheng, Baijun; Lu, Shun

2014-01-01

Formononetin is a novel herbal isoflavonoid isolated from Astragalus membranaceus and possesses antitumorigenic properties. In the present study, we investigated the anti-proliferative effects of formononetin on human non-small cell lung cancer (NSCLC), and further elucidated the molecular mechanism underlying the anti-tumor property. MTT assay showed that formononetin treatment significantly inhibited the proliferation of two NSCLC cell lines including A549 and NCI-H23 in a time- and dose-dependent manner. Flow cytometric analysis demonstrated that formononetin induced G1-phase cell cycle arrest and promoted cell apoptosis in NSCLC cells. On the molecular level, we observed that exposure to formononetin altered the expression levels of cell cycle arrest-associated proteins p21, cyclin A and cyclin D1. Meanwhile, the apoptosis-related proteins cleaved caspase-3, bax and bcl-2 were also changed following treatment with formononetin. In addition, the expression level of p53 was dose-dependently upregulated after administration with formononetin. We also found that formononetin treatment increased the phosphorylation of p53 at Ser15 and Ser20 and enhances its transcriptional activity in a dose-dependent manner. Collectively, these results demonstrated that formononetin might be a potential chemopreventive drug for lung cancer therapy through induction of cell cycle arrest and apoptosis in NSCLC cells.

Induction and repair of DNA double-strand breaks in rat cerebellar cortex exposed to 60Co γ-rays

NASA Astrophysics Data System (ADS)

Bulanova, T. S.; Zadneprianetc, M. G.; Ježková, L.; Kruglyakova, E. A.; Smirnova, E. V.; Boreyko, A. V.

2018-01-01

The induction and repair of DNA double-strand breaks are studied using the immunohistochemical staining procedure of paraffin-embedded rat cerebellum tissues after exposure to γ-rays of 60Co. The dose dependence of radiation-induced colocalized γH2AX/53BP1 foci is studied and its linear character is established. It is shown that these foci are efficiently eliminated 24 h after irradiation.

Role of tumor necrosis factor-α and interleukin-1β in anorexia induction following oral exposure to the trichothecene deoxynivalenol (vomitoxin) in the mouse.

PubMed

Wu, Wenda; Zhang, Haibin

2014-01-01

The trichothecene deoxynivalenol (DON), a foodborne mycotoxin found in grain-based foods, has been associated with human and animal food poisoning. Although induction of anorexia has been described as a hallmark of DON-induced toxicity in many animal species, the mechanistic basis for this adverse effect is not fully understood. The purpose of this research was to determine the role of two proinflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in DON-induced anorexia. In a nocturnal mouse food consumption model, DON-induced anorectic response occurred at 1 hr and lasted up to 6 hr. Similar anorectic effects were observed following acute administration of exogenous TNF-α and IL-1β. Oral exposure to DON at 5 mg/kg bw stimulated splenic and hepatic mRNA and plasma protein elevations of TNF-α and IL-1β that corresponded to anorexia induction. Pretreatment with the TNF-α receptor (TNFR) antagonist R-7050 dose-dependently attenuated both TNF-α- and DON-induced anorexia. While, the type 1 IL-1 receptor (IL-1R1) antagonist IL-1RA dose-dependently attenuated both IL-1β- and DON-induced anorexia. Taken together, the results suggest that both TNF-α and IL-1β play contributory role in anorexia induction following oral exposure to DON.

Cytochrome P450 1A induction in gudgeon Gobio gobio : Laboratory and Field Studies.

PubMed

Flammarion, P

1999-01-01

The induction of cytochrome P450 1A was studied in gudgeon (Gobio gobio), a common European cyprinid, using both farm-raised and field-caught fish. The effects of sex, reproductive status and past exposure to xenobiotics were assessed. When exposed to beta-naphthoflavone (bNF), reared gudgeon showed a dose-dependent increase of EROD activity with a plateau observed at doses from 20 mg kg-1 (females) and 5 mg kg-1 (males). The sexual difference in EROD activity was related to the gonadosomatic index (GSI) of the female whatever the level of induction. Dose and sex effects were confirmed by the immunodetection of CYP1A protein. More than 1 month was necessary for EROD activity to decrease to baseline levels. A second bNF injection after 32 days gave similar levels of induction, suggesting that EROD induction by bNF was not impaired by a pretreatment. Wild fish were brought from two sites in the Rhone river basin: a low contaminated site (Ain) and a highly contaminated site (Rhone). Wild gudgeon were highly induced by bNF in laboratory conditions, except males from the Rhone site which exhibited EROD levels as high as the EROD plateau found in laboratory conditions. A 2- month depuration period in clean water was necessary for EROD activity in wild gudgeon to decrease to baseline levels. These results provide better knowledge of the main factors of modulation of the induction in gudgeon as well as on the influence of the history of exposure to inducers.

Dual effects of phloretin on aflatoxin B1 metabolism: activation and detoxification of aflatoxin B1.

PubMed

Gao, Shang Shang; Chen, Xiao Yan; Zhu, Ri Zhe; Choi, Byung-Min; Kim, Sun Jun; Kim, Bok-Ryang

2012-01-01

Typically, chemopreventive agents involve either induction of phase II detoxifying enzymes and/or inhibition of cytochrome P450 enzymes (CYPs) that are required for the activation of procarcinogens. In this study, we investigated the protective effects of phloretin against aflatoxin B1 (AFB1) activation to the ultimate carcinogenic intermediate, AFB(1)-8, 9-epoxide (AFBO), and its subsequent detoxification. Phloretin markedly inhibited formation of the epoxide with human liver microsomes in a dose-dependent manner. Phloretin also inhibited the activities of nifedipine oxidation and ethoxyresorufin O-deethylase (EROD) in human liver microsomes. These data show that phloretin strongly inhibits CYP1A2 and CYP3A4 activities, which are involved in the activation of AFB1. Phloretin increased glutathione S-transferase (GST) activity of alpha mouse liver 12 (AML 12) cells in a dose-dependent manner. GST activity toward AFBO in cell lysates treated with 20 μM phloretin was 23-fold that of untreated control cell lysates. The expression of GSTA3, GSTA4, GSTM1, GSTP1 and GSTT1 was induced by phloretin in a dose-dependent manner in AML 12 cells. GSTP1, GSTM1, and GSTT1 were able to significantly increase the conjugation of AFBO with glutathione. Concurrently, induction of the GST isozyme genes was partially associated with the Nrf2/ARE pathway. Taken together, the results demonstrate that phloretin has a strong chemopreventive effect against AFB1 through its inhibitory effect on CYP1A2, CYP3A4, and its inductive effect on GST activity. Copyright © 2012 International Union of Biochemistry and Molecular Biology, Inc.

Analysis of mutagenic DNA repair in a thermoconditional mutant of Saccharomyces cerevisiae. IV. Influence of DNA replication and excision repair on REV2 dependent UV-mutagenesis and repair.

PubMed

Siede, W; Eckardt, F

1986-01-01

A double mutant being thermoconditionally defective in mutation induction as well as in repair of pre-lethal UV-induced DNA damage (rev2ts) and deficient in excision repair (rad3-2) was studied in temperature-shift experiments. The influence of inhibitors of DNA replication (hydroxyurea, aphidicolin) was determined. Additionally, an analysis of the dose-response pattern of mutation induction ("mutation kinetics") at several ochre alleles was carried out. It was concluded that the UV-inducible REV2 dependent mutagenic repair process is not induced in excision-deficient cells. In excision-deficient cells, REV2 dependent mutation fixation is slow and mostly post-replicative though not dependent on DNA replication. The REV2 mediated mutagenic process could be separated from the repair function.

Impact of Cannabis Use During Stabilization on Methadone Maintenance Treatment

PubMed Central

Scavone, Jillian L.; Sterling, Robert C.; Weinstein, Stephen P.; Van Bockstaele, Elisabeth J.

2016-01-01

Background and Objectives Illicit drug use, particularly of cannabis, is common among opiate-dependent individuals, and has the potential to impact treatment in a negative manner. Methods To examine this, patterns of cannabis use prior to and during methadone maintenance treatment (MMT) were examined to assess possible cannabis-related effects on MMT, particularly during methadone stabilization. Retrospective chart analysis was used to examine outpatient records of patients undergoing MMT (n=91), focusing specifically on past and present cannabis use and its association with opiate abstinence, methadone dose stabilization, and treatment compliance. Results Objective rates of cannabis use were high during methadone induction, dropping significantly following dose stabilization. History of cannabis use correlated with cannabis use during MMT, but did not negatively impact the methadone induction process. Pilot data also suggested that objective ratings of opiate withdrawal decrease in MMT patients using cannabis during stabilization. Conclusions and Scientific Significance The present findings may point to novel interventions to be employed during treatment for opiate dependence that specifically target cannabinoid-opioid system interactions. PMID:23795873

Risk-Taking Propensity as a Predictor of Induction onto Naltrexone Treatment for Opioid Dependence

PubMed Central

Aklin, Will M.; Severtson, S. Geoffrey; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E.; Lejuez, C. W.; Silverman, Kenneth

2014-01-01

Objective Heroin addiction is a chronic relapsing disorder that has devastating social, medical, and economic consequences. Naltrexone is an antagonist that blocks opioid effects and could be an effective medication for the treatment of opioid dependence. However, its clinical utility has been limited partly because of poor adherence and acceptability. Given the importance of compliance to naltrexone treatment for opioid dependence, the goal of the current study was to examine predictors involved in successful induction onto naltrexone treatment. Method Parametric and nonparametric statistical tests were performed on data from a sample of 64 individuals entering treatment who met DSM-IV criteria for opioid dependence. The relationship between naltrexone induction (i.e., inducted- vs. not-inducted onto naltrexone) and risk-taking propensity, as indexed by riskiness on the Balloon Analogue Risk Task (BART) was examined. Participants were recruited from local detoxification programs, inpatient drug treatment, and other Baltimore programs that provided services to opioid dependent adults (e.g., Baltimore Needle Exchange Program) during the period from August 2007 to September 2008. Results Positive association between risk-taking propensity and odds of naltrexone induction. Specifically, each five point increase in the total BART score was associated with a 25% decrease in odds of naltrexone induction (OR=0.76, 95% CI: 0.58–0.99, p = .041). This association remained statistically significant even after adjusting for potential confounds, including injection drug use and cocaine positive urine results (p = .05). After adjusting for the covariates, each five point increase in BART score was associated with 28% decrease in the odds of achieving the maintenance dose (AOR=0.73, 95% CI: 0.54–0.99, p = .046). Conclusions Risk taking propensity was predictive of induction onto naltrexone treatment, above and beyond injection drug use and cocaine-positive urine samples. PMID:22967782

Binding of antibodies to the extractable nuclear antigens SS-A/Ro and SS-B/La is induced on the surface of human keratinocytes by ultraviolet light (UVL): Implications for the pathogenesis of photosensitive cutaneous lupus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Furukawa, F.; Kashihara-Sawami, M.; Lyons, M.B.

1990-01-01

Autoantibodies to the non-histone nucleoprotein antigens SS-A/Ro, SS-B/La, and RNP are highly associated with photosensitive cutaneous lupus erythematosus (LE). In order to better understand the potential mechanisms of ultraviolet (UV) light on photosensitivity in patients with cutaneous LE, we designed immunopathologic in vitro and in vivo experiments to evaluate the effects of UV on the binding of such autoantibodies to the surface of human keratinocytes, one major target of immunologic damage in photosensitive LE. Short-term 2% paraformaldehyde fixation of suspensions of cultured human keratinocytes previously incubated with monospecific antiserum probes enabled the detection of ENA expression on the cell surfacemore » by flow-cytometry analysis. UVB light (280-320 nm) induced the binding of monospecific antibody probes for SS-A/Ro and SS-B/La on keratinocytes in a dose-dependent pattern with maximal induction observed at the dose of 200 mJ/cm2 UVB. Binding of SS-A/Ro, SS-B/La, and RNP antibody was augmented strongly, but binding of anti-Sm was very weak. In contrast, UVA (320-400 nm) light had no effect on the induction of binding of these antibody probes. Identical results were seen by standard immunofluorescence techniques. Hydroxyurea-treated keratinocytes showed similar induction of those antigens by UVB irradiation, which suggested that ENA expression on cultured keratinocytes by UVB were cell-cycle independent. Tunicamycin, an inhibitor of glycosylation of proteins, reduced UVB light effect on the SS-A/Ro and SS-B/La antigen's expression. These in vitro FACS analyses revealed that ENA augmentation on the keratinocyte cell surface was dose dependent, UVB dependent, glycosylation dependent, and cell-cycle independent. In vivo ENA augmentation on the keratinocyte surface was examined in suction blister epidermal roofs.« less

Increased sensitivity to apoptosis induced by methotrexate is mediated by Jun N-terminal kinase

PubMed Central

Spurlock, Charles F.; Aune, Zachary T.; Tossberg, John T.; Collins, Patrick L.; Aune, Jessica P.; Huston, Joseph W.; Crooke, Philip S.; Olsen, Nancy J.; Aune, Thomas M.

2011-01-01

Objective Low-dose methotrexate [MTX] is an effective therapy for rheumatoid arthritis yet its mechanism of action is incompletely understood. Here, we explored induction of apoptosis by MTX. Methods We employed flow cytometry to assess changes in levels of intracellular proteins, reactive oxygen species [ROS], and apoptosis.Quantitative polymerase chain reaction was usedtoassess changes in transcript levels of select target genes in response to MTX. Results MTX does not directly induce apoptosis but rather ‘primes’ cells for markedly increased sensitivity to apoptosis via either mitochondrial or death receptor pathways by a Jun N-terminal kinase [JNK]-dependent mechanism. Increased sensitivity to apoptosis is mediated, at least in part, by MTX-dependent production of reactive oxygen species, JNK activation and JNK-dependent induction of genes whose protein products promote apoptosis. Supplementation with tetrahydrobiopterin blocks these methotrexate-induced effects. Subjects with rheumatoid arthritis on low-dose MTX therapy express elevated levels of the JNK-target gene, JUN. Conclusions Our results support a model whereby methotrexate inhibits reduction of dihydrobiopterin to tetrahydrobiopterin resulting in increased production of ROS, increased JNK activity and increased sensitivity to apoptosis. The finding of increased JUN levels in subjects with RA taking low-dose MTX supports the notion that this pathway is activated by MTX, in vivo, and may contribute to efficacy of MTX in inflammatory disease. PMID:21618198

Formononetin suppresses the proliferation of human non-small cell lung cancer through induction of cell cycle arrest and apoptosis

PubMed Central

Yang, Yi; Zhao, Yi; Ai, Xinghao; Cheng, Baijun; Lu, Shun

2014-01-01

Formononetin is a novel herbal isoflavonoid isolated from Astragalus membranaceus and possesses antitumorigenic properties. In the present study, we investigated the anti-proliferative effects of formononetin on human non-small cell lung cancer (NSCLC), and further elucidated the molecular mechanism underlying the anti-tumor property. MTT assay showed that formononetin treatment significantly inhibited the proliferation of two NSCLC cell lines including A549 and NCI-H23 in a time- and dose-dependent manner. Flow cytometric analysis demonstrated that formononetin induced G1-phase cell cycle arrest and promoted cell apoptosis in NSCLC cells. On the molecular level, we observed that exposure to formononetin altered the expression levels of cell cycle arrest-associated proteins p21, cyclin A and cyclin D1. Meanwhile, the apoptosis-related proteins cleaved caspase-3, bax and bcl-2 were also changed following treatment with formononetin. In addition, the expression level of p53 was dose-dependently upregulated after administration with formononetin. We also found that formononetin treatment increased the phosphorylation of p53 at Ser15 and Ser20 and enhances its transcriptional activity in a dose-dependent manner. Collectively, these results demonstrated that formononetin might be a potential chemopreventive drug for lung cancer therapy through induction of cell cycle arrest and apoptosis in NSCLC cells. PMID:25674209

Rosuvastatin protects against angiotensin II-induced renal injury in a dose-dependent fashion.

PubMed

Park, Joon-Keun; Mervaala, Eero Ma; Muller, Dominik N; Menne, Jan; Fiebeler, Anette; Luft, Friedrich C; Haller, Hermann

2009-03-01

We showed earlier that statin treatment ameliorates target-organ injury in a transgenic model of angiotensin (Ang) II-induced hypertension. We now test the hypothesis that rosuvastatin (1, 10, and 50 mg/kg/day) influences leukocyte adhesion and infiltration, prevents induction of inducible nitric oxide synthase (iNOS), and ameliorates target-organ damage in a dose-dependent fashion. We treated rats harboring the human renin and human angiotensinogen genes (dTGR) from week 4 to 8 (n = 20 per group). Untreated dTGR developed severe hypertension, cardiac hypertrophy, and renal damage, with a 100-fold increased albuminuria and focal cortical necrosis. Mortality of untreated dTGR at age 8 weeks was 59%. Rosuvastatin treatment decreased mortality dose-dependently. Blood pressure was not affected. Albuminuria was reduced dose-dependently. Interstitial adhesion molecule (ICAM)-1 expression was markedly reduced by rosuvastatin, as were neutrophil and monocyte infiltration. Immunohistochemistry showed an increased endothelial and medial iNOS expression in small vessels, infiltrating cells, afferent arterioles, and glomeruli of dTGR. Immunoreactivity was stronger in cortex than medulla. Rosuvastatin markedly reduced the iNOS expression in both cortex and medulla. Finally, matrix protein (type IV collagen, fibronectin) expression was also dose- dependently reduced by rosuvastatin. Our findings indicate that rosuvastatin dose- dependently ameliorates angiotensin II-induced-organ damage and almost completely prevents inflammation at the highest dose. The data implicate 3-hydroxy-3-methylglutaryl coenzyme A function in signaling events leading to target-organ damage.

Estimation of the radiation-induced DNA double-strand breaks number by considering cell cycle and absorbed dose per cell nucleus

PubMed Central

Mori, Ryosuke; Matsuya, Yusuke; Yoshii, Yuji; Date, Hiroyuki

2018-01-01

Abstract DNA double-strand breaks (DSBs) are thought to be the main cause of cell death after irradiation. In this study, we estimated the probability distribution of the number of DSBs per cell nucleus by considering the DNA amount in a cell nucleus (which depends on the cell cycle) and the statistical variation in the energy imparted to the cell nucleus by X-ray irradiation. The probability estimation of DSB induction was made following these procedures: (i) making use of the Chinese Hamster Ovary (CHO)-K1 cell line as the target example, the amounts of DNA per nucleus in the logarithmic and the plateau phases of the growth curve were measured by flow cytometry with propidium iodide (PI) dyeing; (ii) the probability distribution of the DSB number per cell nucleus for each phase after irradiation with 1.0 Gy of 200 kVp X-rays was measured by means of γ-H2AX immunofluorescent staining; (iii) the distribution of the cell-specific energy deposition via secondary electrons produced by the incident X-rays was calculated by WLTrack (in-house Monte Carlo code); (iv) according to a mathematical model for estimating the DSB number per nucleus, we deduced the induction probability density of DSBs based on the measured DNA amount (depending on the cell cycle) and the calculated dose per nucleus. The model exhibited DSB induction probabilities in good agreement with the experimental results for the two phases, suggesting that the DNA amount (depending on the cell cycle) and the statistical variation in the local energy deposition are essential for estimating the DSB induction probability after X-ray exposure. PMID:29800455

Estimation of the radiation-induced DNA double-strand breaks number by considering cell cycle and absorbed dose per cell nucleus.

PubMed

Mori, Ryosuke; Matsuya, Yusuke; Yoshii, Yuji; Date, Hiroyuki

2018-05-01

DNA double-strand breaks (DSBs) are thought to be the main cause of cell death after irradiation. In this study, we estimated the probability distribution of the number of DSBs per cell nucleus by considering the DNA amount in a cell nucleus (which depends on the cell cycle) and the statistical variation in the energy imparted to the cell nucleus by X-ray irradiation. The probability estimation of DSB induction was made following these procedures: (i) making use of the Chinese Hamster Ovary (CHO)-K1 cell line as the target example, the amounts of DNA per nucleus in the logarithmic and the plateau phases of the growth curve were measured by flow cytometry with propidium iodide (PI) dyeing; (ii) the probability distribution of the DSB number per cell nucleus for each phase after irradiation with 1.0 Gy of 200 kVp X-rays was measured by means of γ-H2AX immunofluorescent staining; (iii) the distribution of the cell-specific energy deposition via secondary electrons produced by the incident X-rays was calculated by WLTrack (in-house Monte Carlo code); (iv) according to a mathematical model for estimating the DSB number per nucleus, we deduced the induction probability density of DSBs based on the measured DNA amount (depending on the cell cycle) and the calculated dose per nucleus. The model exhibited DSB induction probabilities in good agreement with the experimental results for the two phases, suggesting that the DNA amount (depending on the cell cycle) and the statistical variation in the local energy deposition are essential for estimating the DSB induction probability after X-ray exposure.

Biochemical Kinetics Model of DSB Repair and GammaH2AX FOCI by Non-homologous End Joining

NASA Technical Reports Server (NTRS)

Cucinotta, Francis, A.; Pluth, Janice M.; Anderson, Jennifer A.; Harper, Jane V.; O'Neill, Peter

2007-01-01

We developed a biochemical kinetics approach to describe the repair of double strand breaks (DSB) produced by low LET radiation by modeling molecular events associated with the mechanisms of non-homologous end-joining (NHEJ). A system of coupled non-linear ordinary differential equations describes the induction of DSB and activation pathways for major NHEJ components including Ku(sub 70/80), DNA-PK(sub cs), and the Ligase IV-XRCC4 hetero-dimer. The autophosphorylation of DNA-PK(sub cs and subsequent induction of gamma-H2AX foci observed after ionizing radiation exposure were modeled. A two-step model of DNA-PK(sub cs) regulation of repair was developed with the initial step allowing access of other NHEJ components to breaks, and a second step limiting access to Ligase IV-XRCC4. Our model assumes that the transition from the first to second-step depends on DSB complexity, with a much slower-rate for complex DSB. The model faithfully reproduced several experimental data sets, including DSB rejoining as measured by pulsed-field electrophoresis (PFGE), quantification of the induction of gamma-H2AX foci, and live cell imaging of the induction of Ku(sub 70/80). Predictions are made for the behaviors of NHEJ components at low doses and dose-rates, where a steady-state is found at dose-rates of 0.1 Gy/hr or lower.

Differential anti-tumor activity of coriolus versicolor (Yunzhi) extract through p53- and/or Bcl-2-dependent apoptotic pathway in human breast cancer cells.

PubMed

Ho, Cheong-Yip; Kim, Chi-Fai; Leung, Kwok-Nam; Fung, Kwok-Pui; Tse, Tak-Fu; Chan, Helen; Lau, Clara Bik-San

2005-06-01

Coriolus versicolor (CV), also called Yunzhi, has been demonstrated to exert anti-tumor effects on various types of cancer cells, but the underlying mechanism has not been fully elucidated. The present study aimed to evaluate the in vitro anti-tumor activity of a standardized aqueous ethanol extract prepared from CV on four breast cancer cell lines using MTT assay, and test whether the mechanism involves apoptosis induction and modulation of p53 and Bcl-2 protein expressions using cell death detection ELISA, p53 and Bcl-2 ELISAs respectively. Our results demonstrated that the CV extract dose-dependently suppressed the proliferation of three breast tumor cell lines, with ascending order of IC50 values: T-47D, MCF-7, MDA-MB-231, while BT-20 cells were not significantly affected. Tumoricidal activity of the CV extract was found to be comparable to a chemotherapeutic anti-cancer drug, mitomycin C. Nucleosome productions in apoptotic MDA-MB-231, MCF-7 and T-47D cells were significantly augmented in a time-dependent manner and paralleled the anti-proliferative activity of CV extract. Expression of p53 protein was significantly upregulated only in T-47D cells treated with the CV extract in a dose- and time-dependent fashion, but not in MCF-7 (except at 400 mug/ml after 16 h) and MDA-MB-231 cells. The CV extract significantly induced a dose-dependent downregulation of Bcl-2 protein expression in MCF-7 and T-47D cells, but not in MDA-MB-231 cells. These results suggested that apoptosis induction, differentially dependent of p53 and Bcl-2 expressions, might be the possible mechanism of CV extract-mediated cytotoxicity in human breast cancer cells in vitro.

DNA strand breaks signal the induction of DNA double-strand break repair in Saccharomyces cerevisiae.

PubMed

Singh, Rakesh Kumar; Krishna, Malini

2005-12-01

Genotoxic stress induces a checkpoint signaling cascade to generate a stress response. Saccharomyces cerevisiae shows an altered radiation response under different type of stress. Although the induction of repair has been implicated in enhanced survival after exposure to the challenging stress, the nature of the signal remains poorly understood. This study demonstrates that low doses of gamma radiation and bleomycin induce RAD52-dependent recombination repair pathway in the wild-type strain D-261. Prior exposure of cells to DNA-damaging agents (gamma radiation or bleomycin) equips them better for the subsequent damage caused by challenging doses. However, exposure to UV light, which does not cause strand breaks, was ineffective. This was confirmed by PFGE studies. This indicates that the strand breaks probably serve as the signal for induction of the recombination repair pathway while pyrimidine dimers do not. The nature of the induced repair was investigated by mutation scoring in special strain D-7, which showed that the induced repair is essentially error free.

Role of Glucagon-Like Peptide-1 and Gastric Inhibitory Peptide in Anorexia Induction Following Oral Exposure to the Trichothecene Mycotoxin Deoxynivalenol (Vomitoxin).

PubMed

Jia, Hui; Wu, Wen-Da; Lu, Xi; Zhang, Jie; He, Cheng-Hua; Zhang, Hai-Bin

2017-09-01

Deoxynivalenol (DON), which is a Type B trichothecene mycotoxin produced by Fusarium, frequently contaminates cereal staples, such as wheat, barley and corn. DON threatens animal and human health by suppressing food intake and impairing growth. While anorexia induction in mice exposed to DON has been linked to the elevation of the satiety hormones cholecystokinin and peptide YY3-36 in plasma, the effects of DON on the release of other satiety hormones, such as glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), have not been established. The purpose of this study was to determine the roles of GLP-1 and GIP in DON-induced anorexia. In a nocturnal mouse food consumption model, the elevation of plasma GLP-1 and GIP concentrations markedly corresponded to anorexia induction by DON. Pretreatment with the GLP-1 receptor antagonist Exendin9-39 induced a dose-dependent attenuation of both GLP-1- and DON-induced anorexia. In contrast, the GIP receptor antagonist Pro3GIP induced a dose-dependent attenuation of both GIP- and DON-induced anorexia. Taken together, these results suggest that GLP-1 and GIP play instrumental roles in anorexia induction following oral exposure to DON, and the effect of GLP-1 is more potent and long-acting than that of GIP. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Apoptotic induction of skin cancer cell death by plant extracts.

PubMed

Thuncharoen, Walairat; Chulasiri, Malin; Nilwarangkoon, Sirinun; Nakamura, Yukio; Watanapokasin, Ramida

2013-01-01

The aim of the present study was to investigate the effects of plant extracts on cancer apoptotic induction. Human epidermoid carcinoma A431 cell line, obtained from the American Type Culture Collection (ATCC, Manassas, VA), was maintained in Dulbecco's Modified Eagle Medium (DMEM) supplemented with 10% fetal bovine serum (FBS) at 37 degrees C, 5% carbon dioxide (CO2). Plant extract solutions were obtained from S & J international enterprises public company limited. These plant extracts include 50% hydroglycol extracts from Etlingera elatior (Jack) R.M.Smith (torch ginger; EE), Rosa damascene (damask rose; DR) and Rafflesia kerrii Meijer (bua phut; RM). The cell viability, time and dose dependency were determined by MTT (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. A431 cells were treated with the plant extracts and stained with Hoechst 33342 fluorescent staining dye. Cell viability was demonstrated by the inhibitory concentration 50% (IC50). The anti-proliferative effects were shown to be dependent on time and dose. Typical characteristics of apoptosis which are cell morphological changes and chromatin condensation were clearly observed. The plant extracts was shown to be effective for anti-proliferation and induction of apoptosis cell death in skin cancer cells. Therefore, mechanisms underlying the cell death and its potential use for treatment of skin cancer will be further studied.

Induction of defence gene expression by oligogalacturonic acid requires increases in both cytosolic calcium and hydrogen peroxide in Arabidopsis thaliana.

PubMed

Hu, Xiang Yang; Neill, Steven J; Cai, Wei Ming; Tang, Zhang Cheng

2004-06-01

Responses to oligogalacturonic acid (OGA) were determined in transgenic Arabidopsis thaliana seedlings expressing the calcium reporter protein aequorin. OGA stimulated a rapid, substantial and transient increase in the concentration of cytosolic calcium ([Ca2+]cyt) that peaked after ca. 15 s. This increase was dose-dependent, saturating at ca. 50 ug Gal equiv/ml of OGA. OGA also stimulated a rapid generation of H2O2. A small, rapid increase in H2O2 content was followed by a much larger oxidative burst, with H2O2 content peaking after ca. 60 min and declining thereafter. Induction of the oxidative burst by OGA was also dose-dependent, with a maximum response again being achieved at ca. 50 ug Gal equiv/mL. Inhibitors of calcium fluxes inhibited both increases in [Ca2+]cyt and [H2O2], whereas inhibitors of NADPH oxidase blocked only the oxidative burst. OGA increased strongly the expression of the defence-related genes CHS, GST, PAL and PR-1. This induction was suppressed by inhibitors of calcium flux or NADPH oxidase, indicating that increases in both cytosolic calcium and H2O2 are required for OGA-induced gene expression.

A study of normoxic polymer gel using monomer 2-hydroxyethyl methacrylate (HEMA)

NASA Astrophysics Data System (ADS)

Ishak, Siti Atiqah; Mustafa, Iskandar Shahrim; Rahman, Azhar Abdul; Moktar, Mohd; Min, Ung Ngie

2015-04-01

The aim of this study is to determine the sensitivity of HEMA-polymer gel mixture consist of monomer 2-hydroxyethyl methacrylate (HEMA) with different types of composition. Several composition of HEMA-polymer gel were fabricated and the gels were irradiated with radiation dose between 10 cGy to 100cGy by using x-ray machine and 100 cGy to 1400 cGy by using 6 MV photon beam energy of linear accelerator. The degree of polymerization was evaluated by using magnetic resonance imaging (MRI) with dependence of R2-dose response. Polymer gel consists of cross-linker, anti-oxidant Tetrakis(Hydroxymethyl)phosphonium chloride solution (THPC) and oxygen scavenger hydroquinone shows a stable sensitivity with highest dose dependency. Besides, the results shows the stage polymerization consist of induction, propagation, termination, and chain transfer were dependence with type of chemical mixture and radiation dose. Thus, normoxic HEMA-polymer gel with the different gel formulations can have a better dose resolution and an appropriate recipe must be selected to increase of the sensitivity required and the stability of the dosimeter.

A study of normoxic polymer gel using monomer 2-hydroxyethyl methacrylate (HEMA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ishak, Siti Atiqah; Mustafa, Iskandar Shahrim; Rahman, Azhar Abdul

2015-04-24

The aim of this study is to determine the sensitivity of HEMA-polymer gel mixture consist of monomer 2-hydroxyethyl methacrylate (HEMA) with different types of composition. Several composition of HEMA-polymer gel were fabricated and the gels were irradiated with radiation dose between 10 cGy to 100cGy by using x-ray machine and 100 cGy to 1400 cGy by using 6 MV photon beam energy of linear accelerator. The degree of polymerization was evaluated by using magnetic resonance imaging (MRI) with dependence of R2-dose response. Polymer gel consists of cross-linker, anti-oxidant Tetrakis(Hydroxymethyl)phosphonium chloride solution (THPC) and oxygen scavenger hydroquinone shows a stable sensitivitymore » with highest dose dependency. Besides, the results shows the stage polymerization consist of induction, propagation, termination, and chain transfer were dependence with type of chemical mixture and radiation dose. Thus, normoxic HEMA-polymer gel with the different gel formulations can have a better dose resolution and an appropriate recipe must be selected to increase of the sensitivity required and the stability of the dosimeter.« less

Clinical Drug-Drug Interactions Through Cytochrome P450 3A (CYP3A) for the Selective ALK Inhibitor Alectinib.

PubMed

Morcos, Peter N; Cleary, Yumi; Guerini, Elena; Dall, Georgina; Bogman, Katrijn; De Petris, Luigi; Viteri, Santiago; Bordogna, Walter; Yu, Li; Martin-Facklam, Meret; Phipps, Alex

2017-05-01

The efficacy and safety of alectinib, a central nervous system-active and selective anaplastic lymphoma kinase (ALK) inhibitor, has been demonstrated in patients with ALK-positive (ALK+) non-small cell lung cancer (NSCLC) progressing on crizotinib. Alectinib is mainly metabolized by cytochrome P450 3A (CYP3A) to a major similarly active metabolite, M4. Alectinib and M4 show evidence of weak time-dependent inhibition and small induction of CYP3A in vitro. We present results from 3 fixed-sequence studies evaluating drug-drug interactions for alectinib through CYP3A. Studies NP28990 and NP29042 enrolled 17 and 24 healthy subjects, respectively, and investigated potent CYP3A inhibition with posaconazole and potent CYP3A induction through rifampin, respectively, on the single oral dose pharmacokinetics (PK) of alectinib. A substudy of the global phase 2 NP28673 study enrolled 15 patients with ALK+ NSCLC to determine the effect of multiple doses of alectinib on the single oral dose PK of midazolam, a sensitive substrate of CYP3A. Potent CYP3A inhibition or induction resulted in only minor effects on the combined exposure of alectinib and M4. Multiple doses of alectinib did not influence midazolam exposure. These results suggest that dose adjustments may not be needed when alectinib is coadministered with CYP3A inhibitors or inducers or for coadministered CYP3A substrates. © 2016, The American College of Clinical Pharmacology.

Peroxisome Proliferator-Activated Receptor α Activation Suppresses Cytochrome P450 Induction Potential in Mice Treated with Gemfibrozil.

PubMed

Shi, Cunzhong; Min, Luo; Yang, Julin; Dai, Manyun; Song, Danjun; Hua, Huiying; Xu, Gangming; Gonzalez, Frank J; Liu, Aiming

2017-09-01

Gemfibrozil, a peroxisome proliferator-activated receptor α (PPARα) agonist, is widely used for hypertriglyceridaemia and mixed hyperlipidaemia. Drug-drug interaction of gemfibrozil and other PPARα agonists has been reported. However, the role of PPARα in cytochrome P450 (CYP) induction by fibrates is not well known. In this study, wild-type mice were first fed gemfibrozil-containing diets (0.375%, 0.75% and 1.5%) for 14 days to establish a dose-response relationship for CYP induction. Then, wild-type mice and Pparα-null mice were treated with a 0.75% gemfibrozil-containing diet for 7 days. CYP3a, CYP2b and CYP2c were induced in a dose-dependent manner by gemfibrozil. In Pparα-null mice, their mRNA level, protein level and activity were induced more than those in wild-type mice. So, gemfibrozil induced CYP, and this action was inhibited by activated PPARα. These data suggested that the induction potential of CYPs was suppressed by activated PPARα, showing a potential role of this receptor in drug-drug interactions and metabolic diseases treated with fibrates. © 2017 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Dual regulation of skin sensitizer-induced HMOX1 expression by Bach1 and Nrf2: Comparison to regulation of the AKR1C2-ARE element in the KeratinoSens cell line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Emter, Roger; Natsch, Andreas, E-mail: andreas.natsch@givaudan.com

2015-11-01

Heme oxygenase (decycling) 1 (HMOX1) is the most consistently found genetic marker induced by skin sensitizers. HMOX1 is often referred to as typical gene regulated by nuclear factor erythroid 2-related factor 2 (Nrf2), however, it is also regulated by other DNA-binding factors, including BTB and CNC homolog 1 (Bach1). The KeratinoSens™ assay is the first validated in vitro assay for sensitizers that measures gene induction. It is based on luciferase expression regulated by the antioxidant response element (ARE) of the aldoketoreductase 1C2 (AKR1C2) gene. Luciferase upregulation is dependent on Nrf2, while HMOX1 upregulation is only partially Nrf2-dependent. Thus, sensitizer-dependent activationmore » of HMOX1 may integrate multiple signals thereby providing additional information. We constructed reporter cell lines containing the full HMOX1 regulatory region or the HMOX1-ARE sequence and compared them with the construct containing the AKR1C2-ARE sequence. Induction of the AKR1C2-ARE depends on Nrf2, but not on the repressor Bach1. Results obtained with HMOX1-ARE and the full HMOX1 promoter indicate that, within the HMOX1 promoter, the HMOX1-ARE is sufficient to explain the induction by sensitizers and that (i) inhibiting Bach1 leads to strong basal expression, (ii) fold-induction by sensitizers above this level is reduced in the absence of Bach1 and (iii) these constructs are less dependent on Nrf2 as compared to the AKR1C2-ARE. Nevertheless, congruent dose response curves for luciferase activity were obtained with all constructs. Thus, while sensitizer-induced HMOX1 activation is dependent on Nrf2 and Bach1, all constructs give identical information for the in vitro prediction of the sensitization potential. - Highlights: • HMOX1 is a key genetic marker up-regulated by skin sensitizers. • HMOX1-, but not AKR1C2-upregulation, is dependent on both Nrf2 and Bach1. • AKR1C2 and HMOX1-dependent reporter constructs yield congruent dose response curves. • Combining both constructs offers no advantage over either construct used alone.« less

Vitamin K2 alleviates type 2 diabetes in rats by induction of osteocalcin gene expression.

PubMed

Hussein, Atef G; Mohamed, Randa H; Shalaby, Sally M; Abd El Motteleb, Dalia M

2018-03-01

The biological mechanisms behind the association between vitamin K (Vit K) and glucose metabolism are uncertain. We aimed to analyze the expression of insulin 1 (Ins 1), insulin 2 (Ins 2) and cyclin D2, the expression of adiponectin and UCP-1 . In addition, we aimed to estimate the doses of Vit K2 able to affect various aspects of glucose and energy metabolism in type 2 diabetes. Thirty adult male rats were allocated equally into five groups: control group, diabetes mellitus group, and groups 3, 4, and 5, which received Vit K 2 at three daily dose levels (10, 15, and 30 mg/kg, respectively) for 8 wk. At the end of the study, blood samples were collected to quantify total osteocalcin, fasting plasma glucose, fasting insulin, and relevant variables. The expression of OC, Ins 1, Ins 2, cyclin D2, adiponectin, UCP-1 genes was analyzed by real-time polymerase chain reaction. After administration of Vit K 2 , a dose-dependent decrease in fasting plasma glucose, hemoglobin A1c and homeostatic model assessment method insulin resistance, and a dose-dependent increase in fasting insulin and homeostatic model assessment method β cell function levels, when compared with diabetes mellitus rats, were detected. There was significant upregulation of OC, Ins 1, Ins 2, or cyclin D2 gene expression in the three treated groups in a dose-dependent manner when compared with the diabetic rats. However, expression of adiponectin and UCP-1 were significantly increased at the highest dose (30 mg/kg daily) only. Vit K 2 administration could improve glycemic status in type 2 diabetic rats by induction of OC gene expression. Osteocalcin could increase β-cell proliferation, energy expenditure, and adiponectin expression. Different concentrations of Vit K 2 were required to affect glucose metabolism and insulin sensitivity. Copyright © 2017 Elsevier Inc. All rights reserved.

Implication of cyclin-dependent kinase 5 in the development of psychological dependence on and behavioral sensitization to morphine.

PubMed

Narita, Minoru; Shibasaki, Masahiro; Nagumo, Yasuyuki; Narita, Michiko; Yajima, Yoshinori; Suzuki, Tsutomu

2005-06-01

In the present study, we investigated the role of cyclin-dependent kinase 5 (cdk5) in the brain dynamics changed by repeated in vivo treatment with morphine. The level of phosphorylated-cdk5 was significantly increased in the cingulate cortex of mice showing the morphine-induced rewarding effect. Under these conditions, roscovitine, a cdk5 inhibitor, given intracerebroventricularly (i.c.v.) caused a dose-dependent and significant inhibition of the morphine-induced rewarding effect. In addition, the dose-response effect of the morphine-induced rewarding effect was dramatically attenuated in cdk5 heterozygous (+/-) knockout mice. Furthermore, the development of behavioral sensitization by intermittent administration of morphine was virtually abolished in cdk5 (+/-) mice. These findings suggest that the induction and/or activation of cdk5 are implicated in the development of psychological dependence on morphine.

Differential suppression of glial nitric oxide synthase induction by structurally related tyrosine kinase inhibitors.

PubMed

Galea, E; Reddi, J; Feinstein, D L

1995-11-24

Incubation of C6 astrocytoma cells with bacterial endotoxin (lipopolysaccharide; LPS) plus interferon-gamma (IFN-gamma), or with a combination of cytokines (TNF-alpha, IL1-beta, and IFN-gamma) leads to high levels of inducible nitric oxide synthase (iNOS) expression. Previous results demonstrated a requirement for tyrosine kinase (TK) activities for iNOS induction. In the present study, a set of structurally related TK inhibitors, the tyrphostins (TYRs), were used to characterize possible differences between LPS and cytokine iNOS induction. All TYRs tested suppressed both types of induction. However, dose-response curves revealed significant differences in the IC50 values obtained for some TYRs (T25 and T56), and significant differences in the IC50 potency rank order when comparing inhibition of LPS versus cytokine-dependent iNOS induction. These results are consistent with differential TK utilization by the LPS versus cytokine pathways of iNOS induction, and establish a basis for developing further selective inhibitors of iNOS expression.

NANOPARTICLE DELIVERED BIOSENSOR FOR REACTIVE OXYGEN SPECIES IN DIABETES

PubMed Central

Prow, Tarl W.; Bhutto, Imran; Grebe, Rhonda; Uno, Koichi; Merges, Carol; Mcleod, D. Scott; Lutty, Gerard A.

2008-01-01

The cell’s own antioxidant response element (ARE) can be used to evaluate the complications of diabetes mellitus. The hypothesis that a synthetic ARE could be used as a genetic switch, or biosensor, to turn on and off therapeutic genes is tested herein. Mitochondrial oxidative stress (MOS) has been hypothesized as one of the earliest insults in diabetes. Fluorescent probes used to monitor MOS revealed that the addition of glucose at physiological levels to cultures of endothelial cells was able to induce MOS above normal levels and in a dose dependant manner. Additional data showed that increased glucose levels activated the ARE-GFP in a dose dependant manner. These data support the hypothesis that the induction of MOS is more sensitive to hyperglycemia than the induction of the ARE. Delivery of an ARE-GFP construct with nanoparticles to the eye was successful using sub-retinal injection. This ARE-GFP/nanoparticle construct was functional and reported the activation of the ARE in diabetic rat retinal pigment epithelium (RPE). These data support the use of nanoparticle delivered biosensors for monitoring the oxidative status of tissues in vivo. PMID:18252237

Nanoparticle-delivered biosensor for reactive oxygen species in diabetes.

PubMed

Prow, Tarl W; Bhutto, Imran; Grebe, Rhonda; Uno, Koichi; Merges, Carol; McLeod, D Scott; Lutty, Gerard A

2008-02-01

The cell's own antioxidant response element (ARE) can be used to evaluate the complications of diabetes mellitus. The hypothesis that a synthetic ARE could be used as a genetic switch, or biosensor, to turn on and off therapeutic genes is tested herein. Mitochondrial oxidative stress (MOS) has been hypothesized as one of the earliest insults in diabetes. Fluorescent probes used to monitor MOS revealed that the addition of glucose at physiological levels to cultures of endothelial cells was able to induce MOS above normal levels and in a dose-dependant manner. Additional data showed that increased glucose levels activated the ARE-GFP in a dose-dependant manner. These data support the hypothesis that the induction of MOS is more sensitive to hyperglycemia than the induction of the ARE. Delivery of an ARE-GFP construct with nanoparticles to the eye was successful using sub-retinal injection. This ARE-GFP/nanoparticle construct was functional and reported the activation of the ARE in diabetic rat retinal pigment epithelium (RPE). These data support the use of nanoparticle-delivered biosensors for monitoring the oxidative status of tissues in vivo.

[In vivo study of the pharmacokinetic interaction of afobazole and losartan (cytochrome CYP2C9 substrate)].

PubMed

Gribakina, O G; Kolyvanov, G B; Litvin, A A; Zherdev, V P; Seredin, S B

2013-01-01

The influence of afobazole on isoenzyme CYP2C9 production in rats was studied using losartan as the marker drug. Single dose of losartan was administered orally without afobazole in a dose of 30 mg/kg and in the same single (30 mg/kg) on the background of 3- and 4-day administration of afobazole in a dose of 5, 25, 75, 100, and 125 mg/kg. At 5 mg/kg (effective dose for anxiolytic effect), afobazole did not cause any induction/inhibition effect on CYP2C9 isoenzyme. A multiple increase in afobazole dose was manifested by a moderate induction effect. The maximum induction effect of afobazole was achieved in a dose of 75 mg/kg. At doses above 75 mg/kg, the induction effect of afobazole was less pronounced.

Radiation-quality dependent cellular response in mutation induction in normal human cells.

PubMed

Suzuki, Masao; Tsuruoka, Chizuru; Uchihori, Yukio; Kitamura, Hisashi; Liu, Cui Hua

2009-09-01

We studied cellular responses in normal human fibroblasts induced with low-dose (rate) or low-fluence irradiations of different radiation types, such as gamma rays, neutrons and high linear energy transfer (LET) heavy ions. The cells were pretreated with low-dose (rate) or low-fluence irradiations (approximately 1 mGy/7-8 h) of 137Cs gamma rays, 241Am-Be neutrons, helium, carbon and iron ions before irradiations with an X-ray challenging dose (1.5 Gy). Helium (LET = 2.3 keV/microm), carbon (LET = 13.3 keV/microm) and iron (LET = 200 keV/microm) ions were produced by the Heavy Ion Medical Accelerator in Chiba (HIMAC), Japan. No difference in cell-killing effect, measured by a colony forming assay, was observed among the pretreatment with different radiation types. In mutation induction, which was detected in the hypoxanthine-guanine phosphoribosyltransferase (hprt) locus to measure 6-thioguanine resistant clones, there was no difference in mutation frequency induced by the X-ray challenging dose between unpretreated and gamma-ray pretreated cells. In the case of the pretreatment of heavy ions, X-ray-induced mutation was around 1.8 times higher in helium-ion pretreated and 4.0 times higher in carbon-ion pretreated cells than in unpretreated cells (X-ray challenging dose alone). However, the mutation frequency in cells pretreated with iron ions was the same level as either unpretreated or gamma-ray pretreated cells. In contrast, it was reduced at 0.15 times in cells pretreated with neutrons when compared to unpretreated cells. The results show that cellular responses caused by the influence of hprt mutation induced in cells pretreated with low-dose-rate or low-fluence irradiations of different radiation types were radiation-quality dependent manner.

Regulation of rat heme oxygenase-1 expression by interleukin-6 via the Jak/STAT pathway in hepatocytes.

PubMed

Tron, Kyrylo; Samoylenko, Anatoly; Musikowski, Gernot; Kobe, Fritz; Immenschuh, Stephan; Schaper, Fred; Ramadori, Giuliano; Kietzmann, Thomas

2006-07-01

Heme oxygenase-1 (HO-1) can be induced by various stimuli, one of which is interleukin-6 (IL-6). Therefore, the aim of this study was to elucidate the molecular mechanisms responsible for IL-6-dependent HO-1 induction in the liver. The IL-6-dependent HO-1 regulation in rat primary hepatocytes and HepG2 hepatoma cells was studied by Northern and Western blot analyses, HO-1 promoter reporter gene assays and EMSA. The HO-1 expression was transcriptionally induced by IL-6 in a time- and dose-dependent manner. Activation of signal transducers and activators of transcription (STAT) factors by the IL-6 receptor was crucial for HO-1 induction. By contrast, negative regulation of HO-1 expression appeared to be mediated through the SH2-domain-containing tyrosine phosphatase-2 (SHP2)/ suppressors of cytokine signaling-3 (SOCS3) binding site within the gp130 IL-6 receptor subunit. Among the three putative STAT binding elements (SBE) in the HO-1 promoter, only the distal one was functional and when deleted, the remaining Luc induction was completely obliterated by the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. The HO-1 SBE3 mediates HO-1 gene induction by IL-6 mainly via activation of the Jak/STAT pathway.

Induction and Processing of the Radiation-Induced Gamma-H2AX Signal and Its Link to the Underlying Pattern of DSB: A Combined Experimental and Modelling Study

PubMed Central

Tommasino, Francesco; Friedrich, Thomas; Jakob, Burkhard; Meyer, Barbara; Durante, Marco; Scholz, Michael

2015-01-01

We present here an analysis of DSB induction and processing after irradiation with X-rays in an extended dose range based on the use of the γH2AX assay. The study was performed by quantitative flow cytometry measurements, since the use of foci counting would result in reasonable accuracy only in a limited dose range of a few Gy. The experimental data are complemented by a theoretical analysis based on the GLOBLE model. In fact, original aim of the study was to test GLOBLE predictions against new experimental data, in order to contribute to the validation of the model. Specifically, the γH2AX signal kinetics has been investigated up to 24 h after exposure to increasing photon doses between 2 and 500 Gy. The prolonged persistence of the signal at high doses strongly suggests dose dependence in DSB processing after low LET irradiation. Importantly, in the framework of our modelling analysis, this is related to a gradually increased fraction of DSB clustering at the micrometre scale. The parallel study of γH2AX dose response curves shows the onset of a pronounced saturation in two cell lines at a dose of about 20 Gy. This dose is much lower than expected according to model predictions based on the values usually adopted for the DSB induction yield (≈ 30 DSB/Gy) and for the γH2AX foci extension of approximately 2 Mbp around the DSB. We show and discuss how theoretical predictions and experimental findings can be in principle reconciled by combining an increased DSB induction yield with the assumption of a larger genomic extension for the single phosphorylated regions. As an alternative approach, we also considered in our model the possibility of a 3D spreading-mechanism of the H2AX phosphorylation around the induced DSB, and applied it to the analysis of both the aspects considered. Our results are found to be supportive for the basic assumptions on which GLOBLE is built. Apart from giving new insights into the H2AX phosphorylation process, experiments performed at high doses are of relevance in the context of radiation therapy, where hypo-fractionated schemes become increasingly popular. PMID:26067661

Quantitative comparison of the results obtained by the multiple-dose guinea pig maximization test and the non-radioactive murine local lymph-node assay for various biocides.

PubMed

Yamano, Tetsuo; Shimizu, Mitsuru; Noda, Tsutomu

2005-07-01

We compared the results of the multiple-dose guinea pig maximization test (GPMT) and the non-radioactive murine local lymph-node assay (LLNA) for various biocides. Thirteen out of 17 positive biocides in the GPMT gave positive results in the LLNA. In the GPMT, the minimum first induction doses ranged over four orders (0.00005-0.5%), while elicitation-threshold doses, which were evaluated using an optimally sensitized group of animals in the multiple-dose studies, ranged over five orders (0.00006-2.8%). In the LLNA, minimum induction doses ranged over more than three orders (0.01-30%). With respect to 13 biocides that were positive in both the GPMT and the LLNA, results were quantitatively compared. When compared after conversion to corresponding area doses (microg/cm), the minimum doses required to elicit skin reaction in guinea pigs were always lower than that for induction in mice with all biocides. Correlation between minimum induction doses from the GPMT and the LLNA seemed poor (r=0.57), while that between minimum induction doses in the LLNA and elicitation-threshold doses in the GPMT was relatively good (r=0.73). The results suggest the possibility to estimate human elicitation-threshold doses, which are definitely lacking in the process of risk assessment for skin-sensitizers, from the data of the LLNA.

Status epilepticus induction has prolonged effects on the efficacy of antiepileptic drugs in the 6-Hz seizure model.

PubMed

Leclercq, Karine; Kaminski, Rafal M

2015-08-01

Several factors may influence the efficacy of antiepileptic drugs (AEDs) in patients with epilepsy, and treatment resistance could be related to genetics, neuronal network alterations, and modification of drug transporters or targets. Consequently, preclinical models used for the identification of potential new, more efficacious AEDs should reflect at least a few of these factors. Previous studies indicate that induction of status epilepticus (SE) may alter drug efficacy and that this effect could be long-lasting. In this context, we wanted to assess the protective effects of mechanistically diverse AEDs in mice subjected to pilocarpine-induced SE in another seizure model. We first determined seizure thresholds in mice subjected to pilocarpine-induced SE in the 6-Hz model, 2 weeks and 8 weeks following SE. We then evaluated the protective effects of mechanistically diverse AEDs in post-SE and control animals. No major differences in 6-Hz seizure susceptibility were observed between control groups, while the seizure threshold of pilocarpine mice at 8 weeks after SE was higher than at 2 weeks and higher than in control groups. Treatment with AEDs revealed major differences in drug response depending on their mechanism of action. Diazepam produced a dose-dependent protection against 6-Hz seizures in control and pilocarpine mice, both at 2 weeks and 8 weeks after SE, but with a more pronounced increase in potency in post-SE animals at 2 weeks. Levetiracetam induced a potent and dose-dependent protection in pilocarpine mice, 2 weeks after SE, while its protective effects were observed only at much higher doses in control mice. Its potency decreased in post-SE mice at 8 weeks and was very limited (30% protection at the highest tested dose) in the control group. Carbamazepine induced a dose-dependent protection at 2 weeks in control mice but only limited effect (50% at the highest tested dose) in pilocarpine mice. Its efficacy deeply decreased in post-SE mice at 8 weeks after SE. Perampanel and phenytoin showed almost comparable protective effects in all groups of mice. These experiments confirm that prior SE may have an impact on both potency and efficacy of AEDs and indicate that this effect may be dependent on the underlying epileptogenic processes. This article is part of a Special Issue entitled "Status Epilepticus". Copyright © 2015 Elsevier Inc. All rights reserved.

Radon induced hyperplasia: effective adaptation reducing the local doses in the bronchial epithelium.

PubMed

Madas, Balázs G

2016-09-01

There is experimental and histological evidence that chronic irritation and cell death may cause hyperplasia in the exposed tissue. As the heterogeneous deposition of inhaled radon progeny results in high local doses at the peak of the bronchial bifurcations, it was proposed earlier that hyperplasia occurs in these deposition hot spots upon chronic radon exposure. The objective of the present study is to quantify how the induction of basal cell hyperplasia modulates the microdosimetric consequences of a given radon exposure. For this purpose, computational epithelium models were constructed with spherical cell nuclei of six different cell types based on histological data. Basal cell hyperplasia was modelled by epithelium models with additional basal cells and increased epithelium thickness. Microdosimetry for alpha-particles was performed by an own-developed Monte-Carlo code. Results show that the average tissue dose, and the average hit number and dose of basal cells decrease by the increase of the measure of hyperplasia. Hit and dose distribution reveal that the induction of hyperplasia may result in a basal cell pool which is shielded from alpha-radiation. It highlights that the exposure history affects the microdosimetric consequences of a present exposure, while the biological and health effects may also depend on previous exposures. The induction of hyperplasia can be considered as a radioadaptive response at the tissue level. Such an adaptation of the tissue challenges the validity of the application of the dose and dose rate effectiveness factor from a mechanistic point of view. As the location of radiosensitive target cells may change due to previous exposures, dosimetry models considering the tissue geometry characteristic of normal conditions may be inappropriate for dose estimation in case of protracted exposures. As internal exposures are frequently chronic, such changes in tissue geometry may be highly relevant for other incorporated radionuclides.

Drug resistance following irradiation of RIF-1 tumors: Influence of the interval between irradiation and drug treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hopwood, L.E.; Davies, B.M.; Moulder, J.E.

1990-09-01

RIF-1 tumors contain a small number of cells (1 to 100 per 10(6) cells) that are resistant to 5-fluorouracil, methotrexate, or adriamycin. The frequency of drug-resistant cells among individual untreated tumors is highly variable. Radiation, delivered in vivo at doses of 3 to 12 Gy, increases the frequency of methotrexate- and 5-fluorouracil-resistant cells, but not the frequency of adriamycin-resistant cells. The magnitude of induction of 5-fluorouracil and methotrexate resistance shows a complex dependence on the radiation dose and on the interval between irradiation and assessment of drug resistance. For a dose of 3 Gy, induced 5-fluorouracil and methotrexate resistance ismore » seen only after an interval of 5 to 7 days, whereas for a dose of 12 Gy, high levels of induced resistance are observed 1 to 3 days after irradiation. The maximum absolute risk for induction of resistance is 4 per 10(4) cells per Gy for methotrexate, and 3 per 10(6) cells per Gy for 5-fluorouracil. These results indicate that tumor hypoxia may play a role in the increased levels of drug resistance seen after irradiation, and that both genetic and environmental factors may influence radiation-induction of drug resistance. These studies provide essential data for models of the development of tumor drug resistance, and imply that some of the drug resistance seen when chemotherapy follows radiotherapy may be caused by radiation-induced drug resistance.« less

Development of HSPA1A promoter-driven luciferase reporter gene assays in human cells for assessing the oxidative damage induced by silver nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xin, Lili, E-mail: llxin@suda.edu.cn

The exponential increase in the total number of engineered nanoparticles in consumer products requires novel tools for rapid and cost-effective toxicology screening. In order to assess the oxidative damage induced by nanoparticles, toxicity test systems based on a human HSPA1A promoter-driven luciferase reporter in HepG2, LO2, A549, and HBE cells were established. After treated with heat shock and a group of silver nanoparticles (AgNPs) with different primary particle sizes, the cell viability, oxidative damage, and luciferase activity were determined. The time-dependent Ag{sup +} ions release from AgNPs in cell medium was also evaluated. Our results showed that heat shock producedmore » a strong time-dependent induction of relative luciferase activity in the four luciferase reporter cells. Surprisingly, at 4 h of recovery, the relative luciferase activity was > 98 × the control level in HepG2-luciferase cells. Exposure to different sizes of AgNPs resulted in activation of the HSPA1A promoter in a dose-dependent manner, even at low cytotoxic or non-cytotoxic doses. The smaller (5 nm) AgNPs were more potent in luciferase induction than the larger (50 and 75 nm) AgNPs. These results were generally in accordance with the oxidative damage indicated by malondialdehyde concentration, reactive oxygen species induction and glutathione depletion, and Ag{sup +} ions release in cell medium. Compared with the other three luciferase reporter cells, the luciferase signal in HepG2-luciferase cells is obviously more sensitive and stable. We conclude that the luciferase reporter cells, especially the HepG2-luciferase cells, could provide a valuable tool for rapid screening of the oxidative damage induced by AgNPs. - Highlights: • We established the stable HSPA1A promoter-driven luciferase reporter cells. • Silver nanoparticles induced dose-dependent increases in luciferase activity. • HSPA1A promoter activity is a sensitive and responsive indicator of oxidative stress. • HepG2-luciferase cells can be used to assess the toxicity of silver nanoparticles.« less

Induction prednisone dosing for childhood nephrotic syndrome: how low should we go?

PubMed

Sibley, Matthew; Roshan, Abishek; Alshami, Alanoud; Catapang, Marisa; Jöbsis, Jasper J; Kwok, Trevor; Polderman, Nonnie; Sibley, Jennifer; Matsell, Douglas G; Mammen, Cherry

2018-05-22

Historically, children with nephrotic syndrome (NS) across British Columbia (BC), Canada have been cared for without formal standardization of induction prednisone dosing. We hypothesized that local historical practice variation in induction dosing was wide and that children treated with lower doses had worse relapsing outcomes. This retrospective cohort study included 92 NS patients from BC Children's Hospital (1990-2010). We excluded secondary causes of NS, age < 1 year at diagnosis, steroid resistance, and incomplete induction due to early relapse. We explored cumulative induction dose and defined dosing quartiles. Relapsing outcomes above and below each quartile threshold were compared including total relapses in 2 years, time to first relapse, and proportions developing frequently relapsing NS (FRNS) or starting a steroid-sparing agent (SSA). Cumulative prednisone was widely distributed with approximated median, 1st, and 3rd quartile doses of 2500, 2000, and 3000 mg/m 2 respectively. Doses ≤ 2000 mg/m 2 showed significantly higher relapses (4.2 vs 2.7), shorter time to first relapse (61 vs 175 days), and higher SSA use (36 vs 14%) compared to higher doses. Doses ≤ 2500 mg/m 2 also showed significantly more relapses (3.9 vs 2.2), quicker first relapse (79 vs 208 days), and higher FRNS (37 vs 17%) and SSA use (28 vs 11%). Relapsing outcomes lacked statistical difference in ≤ 3000 vs > 3000 mg/m 2 doses. Results strongly justify our development of a standardized, province-wide NS clinical pathway to reduce practice variation and minimize under-treatment. The lowest induction prednisone dosing threshold to minimize future relapsing risks is likely between 2000 and 2500 mg/m 2 . Further prospective studies are warranted.

Genotoxicity Revaluation of Three Commercial Nitroheterocyclic Drugs: Nifurtimox, Benznidazole, and Metronidazole

PubMed Central

Buschini, Annamaria; Ferrarini, Lisa; Franzoni, Susanna; Galati, Serena; Lazzaretti, Mirca; Mussi, Francesca; Northfleet de Albuquerque, Cristina; Maria Araújo Domingues Zucchi, Tânia; Poli, Paola

2009-01-01

Nitroheterocyclic compounds are widely used as therapeutic agents against a variety of protozoan and bacterial infections. However, the literature on these compounds, suspected of being carcinogens, is widely controversial. In this study, cytotoxic and genotoxic potential of three drugs, Nifurtimox (NFX), Benznidazole (BNZ), and Metronidazole (MTZ) was re-evaluated by different assays. Only NFX reduces survival rate in actively proliferating cells. The compounds are more active for base-pair substitution than frameshift induction in Salmonella; NFX and BNZ are more mutagenic than MTZ; they are widely dependent from nitroreduction whereas microsomal fraction S9 weakly affects the mutagenic potential. Comet assay detects BNZ- and NFX-induced DNA damage at doses in the range of therapeutically treated patient plasma concentration; BNZ seems to mainly act through ROS generation whereas a dose-dependent mechanism of DNA damaging is suggested for NFX. The lack of effects on mammalian cells for MTZ is confirmed also in MN assay whereas MN induction is observed for NFX and BNZ. The effects of MTZ, that shows comparatively low reduction potential, seem to be strictly dependent on anaerobic/hypoxic conditions. Both NFX and BNZ may not only lead to cellular damage of the infective agent but also interact with the DNA of mammalian cells. PMID:20981287

Genotoxicity revaluation of three commercial nitroheterocyclic drugs: nifurtimox, benznidazole, and metronidazole.

PubMed

Buschini, Annamaria; Ferrarini, Lisa; Franzoni, Susanna; Galati, Serena; Lazzaretti, Mirca; Mussi, Francesca; Northfleet de Albuquerque, Cristina; Maria Araújo Domingues Zucchi, Tânia; Poli, Paola

2009-01-01

Nitroheterocyclic compounds are widely used as therapeutic agents against a variety of protozoan and bacterial infections. However, the literature on these compounds, suspected of being carcinogens, is widely controversial. In this study, cytotoxic and genotoxic potential of three drugs, Nifurtimox (NFX), Benznidazole (BNZ), and Metronidazole (MTZ) was re-evaluated by different assays. Only NFX reduces survival rate in actively proliferating cells. The compounds are more active for base-pair substitution than frameshift induction in Salmonella; NFX and BNZ are more mutagenic than MTZ; they are widely dependent from nitroreduction whereas microsomal fraction S9 weakly affects the mutagenic potential. Comet assay detects BNZ- and NFX-induced DNA damage at doses in the range of therapeutically treated patient plasma concentration; BNZ seems to mainly act through ROS generation whereas a dose-dependent mechanism of DNA damaging is suggested for NFX. The lack of effects on mammalian cells for MTZ is confirmed also in MN assay whereas MN induction is observed for NFX and BNZ. The effects of MTZ, that shows comparatively low reduction potential, seem to be strictly dependent on anaerobic/hypoxic conditions. Both NFX and BNZ may not only lead to cellular damage of the infective agent but also interact with the DNA of mammalian cells.

Apoptosis induction by silica nanoparticles mediated through reactive oxygen species in human liver cell line HepG2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmad, Javed; Ahamed, Maqusood, E-mail: maqusood@gmail.com; Akhtar, Mohd Javed

Silica nanoparticles are increasingly utilized in various applications including agriculture and medicine. In vivo studies have shown that liver is one of the primary target organ of silica nanoparticles. However, possible mechanisms of hepatotoxicity caused by silica nanoparticles still remain unclear. In this study, we explored the reactive oxygen species (ROS) mediated apoptosis induced by well-characterized 14 nm silica nanoparticles in human liver cell line HepG2. Silica nanoparticles (25–200 μg/ml) induced a dose-dependent cytotoxicity in HepG2 cells. Silica nanoparticles were also found to induce oxidative stress in dose-dependent manner indicated by induction of ROS and lipid peroxidation and depletion ofmore » glutathione (GSH). Quantitative real-time PCR and immunoblotting results showed that both the mRNA and protein expressions of cell cycle checkpoint gene p53 and apoptotic genes (bax and caspase-3) were up-regulated while the anti-apoptotic gene bcl-2 was down-regulated in silica nanoparticles treated cells. Moreover, co-treatment of ROS scavenger vitamin C significantly attenuated the modulation of apoptotic markers along with the preservation of cell viability caused by silica nanoparticles. Our data demonstrated that silica nanoparticles induced apoptosis in human liver cells, which is ROS mediated and regulated through p53, bax/bcl-2 and caspase pathways. This study suggests that toxicity mechanisms of silica nanoparticles should be further investigated at in vivo level. -- Highlights: ► We explored the mechanisms of toxicity caused by silica NPs in human liver HepG2 cells. ► Silica NPs induced a dose-dependent cytotoxicity in HepG2 cells. ► Silica NPs induced ROS generation and oxidative stress in a dose-dependent manner. ► Silica NPs were also modulated apoptosis markers both at mRNA and protein levels. ► ROS mediated apoptosis induced by silica NPs was preserved by vitamin C.« less

INHIBITION OF HUMAN AND RAT CYP1A2 BY TCDD AND DIOXIN-LIKE CHEMICALS

EPA Science Inventory

Dioxins have been shown to bind and induce rodent CYP1A2, producing a dose-dependent hepatic sequestration in vivo. The induction of CYP1A2 activity has been used as a noninvasive biomarker for human exposure to dioxins; while there is a consistent relationship between exposure ...

2,2",4,4"-TETRABROMODIPHENYL (PBDE 47) ALTERS THYROID FUNCTION IN THE RAT.

EPA Science Inventory

Two commercial PBDE mixtures, DE-71 and DE-79, cause dose-dependent depletion of serum T4 via induction of UGTs and increased CYP1A1 activity. This work characterized the effect of a major congener, PBDE-47, in DE-71 for effects on hepatic enzymes and thyroid hormones. Female 27...

Radiation-induced mitotic and meiotic aneuploidy in the yeast Saccharomyces cerevisiae.

PubMed

Parry, J M; Sharp, D; Tippins, R S; Parry, E M

1979-06-01

A number of genetic systems are described which in yeast may be used to monitor the induction of chromosome aneuploidy during both mitotic and meiotic cell division. Using these systems we have been able to demonstrate the induction of both monosomic and trisomic cells in mitotically dividing cells and disomic spores in meiotically dividing cells after both UV light and X-ray exposure. The frequency of UV-light-induced monosomic colonies were reduced by post-treatment with photoreactivity light and both UV-light- and X-ray-induced monosomic colonies were reduced by liquid holding post-treatment under non-nutrient conditions. Both responses indicate an involvement of DNA-repair mechanisms in the removal of lesions which may lead to monosomy in yeast. This was further confirmed by the response of an excision-defective yeast strain which showed considerably increased sensitivity to the induction of monosomic colonies by UV-light treatment at low doses. Yeast cultures irradiated at different stages of growth showed variation in their responses to both UV-light and X-rays, cells at the exponential phase of growth show maximum sensitivity to the induction of monosomic colonies at low doses whereas stationary phase cultures showed maximum induction of monosomic colonies at high does. The frequencies of X-ray-induced chromosome aneuploidy during meiosis leading to the production of disomic spores was shown to be dependent upon the stage of meiosis at which the yeast cells were exposed to radiation. Cells which had proceeded beyond the DNA synthetic stage of meiosis were shown to produce disomic spores at considerably lower radiation doses than those cells which had only recently been inoculated into sporulation medium. The results obtained suggest that the yeast sustem may be suitable for the study of sensitivities of the various stages of meiotic cell division to the induction of chromosome aneuploidy after radiation exposure.

Optimization of initial propofol bolus dose for EEG Narcotrend Index-guided transition from sevoflurane induction to intravenous anesthesia in children.

PubMed

Dennhardt, Nils; Boethig, Dietmar; Beck, Christiane; Heiderich, Sebastian; Boehne, Martin; Leffler, Andreas; Schultz, Barbara; Sümpelmann, Robert

2017-04-01

Sevoflurane induction followed by intravenous anesthesia is a widely used technique to combine the benefits of an easier and less traumatic venipuncture after sevoflurane inhalation with a recovery with less agitation, nausea, and vomiting after total intravenous anesthesia (TIVA). Combination of two different anesthetics may lead to unwanted burst suppression in the electroencephalogram (EEG) during the transition phase. The objective of this prospective clinical observational study was to identify the optimal initial propofol bolus dose for a smooth transition from sevoflurane induction to TIVA using the EEG Narcotrend Index (NI). Fifty children aged 1-8 years scheduled for elective pediatric surgery were studied. After sevoflurane induction and establishing of an intravenous access, a propofol bolus dose range 0-5 mg·kg -1 was administered at the attending anesthetist's discretion to maintain a NI between 20 and 64, and sevoflurane was stopped. Anesthesia was continued as TIVA with a propofol infusion dose of 15 mg·kg -1 ·h -1 for the first 15 min, followed by stepwise reduction according to McFarlan's pediatric infusion regime, and remifentanil 0.25 μg·kg -1 ·min -1 . Endtidal concentration of sevoflurane, NI, and hemodynamic data were recorded during the whole study period using a standardized case report form. Propofol plasma concentrations were calculated using the paedfusor dataset and a TIVA simulation program. Median endtidal concentration of sevoflurane at the time of administration of the propofol bolus was 5.1 [IQR 4.7-5.9] Vol%. The median propofol bolus dose was 1.2 [IQR 0.9-2.5] mg·kg -1 and median NI thereafter was 33 [IQR 23-40]. Nine children presented with a NI 13-20 and three children with burst suppression in the EEG (NI 0-12); all of them received an initial propofol bolus dose >2 mg·kg -1 . Regression equation demonstrated that NI 20-64 was achieved with a 95% probability when using a propofol bolus dose of 1 mg·kg -1 after sevoflurane induction. Decrease in mean arterial blood pressure correlated significantly with propofol bolus dose (P = 0.038). After 25 min of TIVA, children younger than 2 years had a higher NI (median difference 14.0, 95%CI: 6.0-20.0, P = 0.001), higher deviations from the expected Narcotend Index (median difference 4.1, 95%CI: 3.9-4.2, P < 0.001) and lower calculated propofol plasma concentrations (median difference 0.2 μg·ml -1 , 95% CI: 0.1-0.3 μg·ml -1 , P < 0.001) than older children. After sevoflurane induction, a reduced propofol bolus dose of 1 mg·kg -1 followed by TIVA according to McFarlan's regime resulted in a NI within the recommended range in children aged 1-8 years. During the course of TIVA, children younger than 2 years displayed higher NI values and more pronounced interindividual variation. Processed EEG monitoring is recommended to find adequate individual age-dependent doses. © 2017 John Wiley & Sons Ltd.

Toxicity of nano- and micro-sized ZnO particles in human lung epithelial cells

NASA Astrophysics Data System (ADS)

Lin, Weisheng; Xu, Yi; Huang, Chuan-Chin; Ma, Yinfa; Shannon, Katie B.; Chen, Da-Ren; Huang, Yue-Wern

2009-01-01

This is the first comprehensive study to evaluate the cytotoxicity, biochemical mechanisms of toxicity, and oxidative DNA damage caused by exposing human bronchoalveolar carcinoma-derived cells (A549) to 70 and 420 nm ZnO particles. Particles of either size significantly reduced cell viability in a dose- and time-dependent manner within a rather narrow dosage range. Particle mass-based dosimetry and particle-specific surface area-based dosimetry yielded two distinct patterns of cytotoxicity in both 70 and 420 nm ZnO particles. Elevated levels of reactive oxygen species (ROS) resulted in intracellular oxidative stress, lipid peroxidation, cell membrane leakage, and oxidative DNA damage. The protective effect of N-acetylcysteine on ZnO-induced cytotoxicity further implicated oxidative stress in the cytotoxicity. Free Zn2+ and metal impurities were not major contributors of ROS induction as indicated by limited free Zn2+ cytotoxicity, extent of Zn2+ dissociation in the cell culture medium, and inductively-coupled plasma-mass spectrometry metal analysis. We conclude that (1) exposure to both sizes of ZnO particles leads to dose- and time-dependent cytotoxicity reflected in oxidative stress, lipid peroxidation, cell membrane damage, and oxidative DNA damage, (2) ZnO particles exhibit a much steeper dose-response pattern unseen in other metal oxides, and (3) neither free Zn2+ nor metal impurity in the ZnO particle samples is the cause of cytotoxicity.

Oral Sulforaphane increases Phase II antioxidant enzymes in the human upper airway

PubMed Central

Riedl, Marc A.; Saxon, Andrew; Diaz-Sanchez, David

2009-01-01

Background Cellular oxidative stress is an important factor in asthma and is thought to be the principle mechanism by which oxidant pollutants such as ozone and particulates mediate their pro-inflammatory effects. Endogenous Phase II enzymes abrogate oxidative stress through the scavenging of reactive oxygen species and metabolism of reactive chemicals. Objective We conducted a placebo-controlled dose escalation trial to investigate the in vivo effects of sulforaphane, a naturally occurring potent inducer of Phase II enzymes, on the expression of glutathione-s-transferase M1 (GSTM1), glutathione-s-transferase P1 (GSTP1), NADPH quinone oxidoreductase (NQO1), and hemoxygenase-1 (HO-1) in the upper airway of human subjects. Methods Study subjects consumed oral sulforaphane doses contained in a standardized broccoli sprout homogenate (BSH). RNA expression for selected Phase II enzymes was measured in nasal lavage cells by RT-PCR before and after sulforaphane dosing. Results All subjects tolerated oral sulforaphane dosing without significant adverse events. Increased Phase II enzyme expression in nasal lavage cells occurred in a dose-dependent manner with maximal enzyme induction observed at the highest dose of 200 grams broccoli sprouts prepared as BSH. Significant increases were seen in all sentinel Phase II enzymes RNA expression compared to baseline. Phase II enzyme induction was not seen with ingestion of non-sulforaphane containing alfalfa sprouts. Conclusion Oral sulforaphane safely and effectively induces mucosal Phase II enzyme expression in the upper airway of human subjects. This study demonstrates the potential of antioxidant Phase II enzymes induction in the human airway as a strategy to reduce the inflammatory effects of oxidative stress. Clinical Implications This study demonstrates the potential of enhancement of Phase II enzyme expression as a novel therapeutic strategy for oxidant induced airway disease. Capsule Summary A placebo-controlled dose escalation trial demonstrated that naturally occurring sulforaphane from broccoli sprouts can induce a potent increase in antioxidant Phase II enzymes in airway cells. PMID:19028145

Induction of tumor necrosis factor alpha by the group- and type-specific polysaccharides from type III group B streptococci.

PubMed Central

Mancuso, G; Tomasello, F; von Hunolstein, C; Orefici, G; Teti, G

1994-01-01

Previous studies suggested that circulating tumor necrosis factor alpha (TNF-alpha) may have a pathophysiologic role in experimental neonatal sepsis induced by group B streptococci (GBS). This study was undertaken to investigate the ability of the type III and group-specific polysaccharides of GBS to induce TNF-alpha production and TNF-alpha-dependent lethality in neonatal rats. The cytokine was detected in plasma samples by the L929 cytotoxicity assay. Intracardiac injections of either polysaccharide induced dose-dependent, transient elevations in plasma TNF-alpha levels that returned to baseline values after 5 h. The group-specific antigen induced significantly higher mean peak TNF-alpha levels than the type III antigen (125 +/- 47 versus 44 +/- 15 U/ml with 70 mg/kg of body weight). Glycogen (70 mg/kg), used as a negative control, did not induce TNF-alpha. The lipopolysaccharide-neutralizing agent polymyxin B did not decrease TNF-alpha levels induced by either polysaccharide, ruling out contamination with endotoxin as a possible cause of TNF-alpha induction. Fifty percent lethal doses of the type III and group-specific antigens given as intracardiac injections were 105 and 16 mg/kg, respectively. Salmonella endotoxin, used as a positive control, had a 50% lethal dose of 0.1 mg/kg. The lethal activities of GBS polysaccharides, as well as endotoxin, were completely prevented by pretreatment of neonatal rats with the respective specific antibodies or anti-murine TNF-alpha serum. To assess the relative importance of the type-specific substance in TNF-alpha induction by whole bacteria, two unrelated GBS transposon mutants devoid of only the type-specific capsular polysaccharide (COH1-13 and COH31-15) were employed. Each of the heat-killed unencapsulated mutants was able to produce plasma TNF-alpha level elevations or TNF-alpha-dependent lethality but was significantly less efficient in these activities than the corresponding encapsulated wild-type strain. These data suggest that the presence of type-specific material on GBS is not necessary for the stimulation of TNF-alpha production. Type III capsular polysaccharide, however, can significantly increase the ability of GBS to induce TNF-alpha. Further studies will be needed to assess the importance of TNF-alpha induction by the group- and type-specific antigens in the pathophysiology of GBS disease. PMID:8005664

A Retrospective Observational Study of Anesthetic Induction Dosing Practices in Female Elderly Surgical Patients: Are We Overdosing Older Patients?

PubMed

Akhtar, Shamsuddin; Heng, Joseph; Dai, Feng; Schonberger, Robert B; Burg, Mathew M

2016-10-01

Despite guidelines suggesting a 25-50 % reduction in induction doses of intravenous anesthetic agents in the elderly (≥65 years), we hypothesized that practitioners were not sufficiently correcting drug administration for age, contributing to an increased incidence of hypotension in older patients undergoing general anesthesia. We conducted a retrospective, observational study in a tertiary-care academic hospital. The study included 768 female patients undergoing gynecologic surgeries who received propofol-based induction of general anesthesia. Weight-adjusted anesthetic induction dosing, age-associated differences in dosing by ASA-PS (American Society of Anesthesiology-Physical Status), and hemodynamic outcomes between younger (18-64 years, n = 537) and older (≥65 years, n = 231) female patients were analyzed. Older patients received lower doses of propofol and midazolam than younger patients (propofol: 2.037 ± 0.783 vs 2.322 ± 0.834 mg/kg, p < 0.001; midazolam: 0.013 ± 0.014 vs 0.023 ± 0.042 mg/kg, p < 0.001). However, practitioners still consistently exceeded the FDA recommended dose (1-1.5 mg/kg) of propofol for elderly patients. There was no significant difference in the doses of fentanyl administered between the two age groups (1.343 ± 0.744 vs 1.363 ± 0.763 μg/kg, p = 0.744), and doses of fentanyl in older patients exceeded the recommended dose (0.5-1.0 μg/kg). Corresponding to observed overdosing of induction agents, older patients experienced larger decreases in post-induction blood pressure and were more likely to receive vasopressor therapy. Anesthetic induction doses of fentanyl and propofol were not sufficiently corrected in older patients in accordance with recommendations. Significantly greater frequency of post-induction hypotension occurred amongst older patients. Quality improvement efforts may lead to improved outcomes in this vulnerable population.

Role of Cholecystokinin in Anorexia Induction Following Oral Exposure to the 8-Ketotrichothecenes Deoxynivalenol, 15-Acetyldeoxynivalenol, 3-Acetyldeoxynivalenol, Fusarenon X, and Nivalenol

PubMed Central

Wu, Wenda; Zhou, Hui-Ren; He, Kaiyu; Pan, Xiao; Sugita-Konishi, Yoshiko; Watanabe, Maiko; Zhang, Haibin; Pestka, James J.

2014-01-01

Cereal grain contamination by trichothecene mycotoxins is known to negatively impact human and animal health with adverse effects on food intake and growth being of particular concern. The head blight fungus Fusarium graminearum elaborates five closely related 8-ketotrichothecene congeners: (1) deoxynivalenol (DON), (2) 3-acetyldeoxynivalenol (3-ADON), (3) 15-acetyldeoxynivalenol (15-ADON), (4) fusarenon X (FX), and (5) nivalenol (NIV). While anorexia induction in mice exposed intraperitoneally to DON has been linked to plasma elevation of the satiety hormones cholecystokinin (CCK) and peptide YY3–36 (PYY3–36), the effects of oral gavage of DON or of other 8-keotrichothecenes on release of these gut peptides have not been established. The purpose of this study was to (1) compare the anorectic responses to the aforementioned 8-ketotrichothecenes following oral gavage at a common dose (2.5 mg/kg bw) and (2) relate these effects to changes plasma CCK and PYY3–36 concentrations. Elevation of plasma CCK markedly corresponded to anorexia induction by DON and all other 8-ketotrichothecenes tested. Furthermore, the CCK1 receptor antagonist SR 27897 and the CCK2 receptor antagonist L-365,260 dose-dependently attenuated both CCK- and DON-induced anorexia, which was consistent with this gut satiety hormone being an important mediator of 8-ketotrichothecene-induced food refusal. In contrast to CCK, PYY3–36 was moderately elevated by oral gavage with DON and NIV but not by 3-ADON, 15-ADON, or FX. Taken together, the results suggest that CCK plays a major role in anorexia induction following oral exposure to 8-ketotrichothecenes, whereas PYY3–36 might play a lesser, congener-dependent role in this response. PMID:24385417

Role of cholecystokinin in anorexia induction following oral exposure to the 8-ketotrichothecenes deoxynivalenol, 15-acetyldeoxynivalenol, 3-acetyldeoxynivalenol, fusarenon X, and nivalenol.

PubMed

Wu, Wenda; Zhou, Hui-Ren; He, Kaiyu; Pan, Xiao; Sugita-Konishi, Yoshiko; Watanabe, Maiko; Zhang, Haibin; Pestka, James J

2014-04-01

Cereal grain contamination by trichothecene mycotoxins is known to negatively impact human and animal health with adverse effects on food intake and growth being of particular concern. The head blight fungus Fusarium graminearum elaborates five closely related 8-ketotrichothecene congeners: (1) deoxynivalenol (DON), (2) 3-acetyldeoxynivalenol (3-ADON), (3) 15-acetyldeoxynivalenol (15-ADON), (4) fusarenon X (FX), and (5) nivalenol (NIV). While anorexia induction in mice exposed intraperitoneally to DON has been linked to plasma elevation of the satiety hormones cholecystokinin (CCK) and peptide YY₃₋₃₆ (PYY₃₋₃₆), the effects of oral gavage of DON or of other 8-keotrichothecenes on release of these gut peptides have not been established. The purpose of this study was to (1) compare the anorectic responses to the aforementioned 8-ketotrichothecenes following oral gavage at a common dose (2.5 mg/kg bw) and (2) relate these effects to changes plasma CCK and PYY₃₋₃₆ concentrations. Elevation of plasma CCK markedly corresponded to anorexia induction by DON and all other 8-ketotrichothecenes tested. Furthermore, the CCK1 receptor antagonist SR 27897 and the CCK2 receptor antagonist L-365,260 dose-dependently attenuated both CCK- and DON-induced anorexia, which was consistent with this gut satiety hormone being an important mediator of 8-ketotrichothecene-induced food refusal. In contrast to CCK, PYY₃₋₃₆ was moderately elevated by oral gavage with DON and NIV but not by 3-ADON, 15-ADON, or FX. Taken together, the results suggest that CCK plays a major role in anorexia induction following oral exposure to 8-ketotrichothecenes, whereas PYY₃₋₃₆ might play a lesser, congener-dependent role in this response.

Elk-3 is a transcriptional repressor of nitric-oxide synthase 2.

PubMed

Chen, Yen-Hsu; Layne, Matthew D; Chung, Su Wol; Ejima, Kuniaki; Baron, Rebecca M; Yet, Shaw-Fang; Perrella, Mark A

2003-10-10

The inducible isoform of nitric-oxide synthase (NOS2), a key enzyme catalyzing the dramatic increase in nitric oxide by lipopolysaccharide (LPS), plays an important role in the pathophysiology of endotoxemia and sepsis. Recent evidence suggests that Ets transcription factors may contribute to NOS2 induction by inflammatory stimuli. In this study, we investigated the role of Ets transcription factors in the regulation of NOS2 by LPS and transforming growth factor (TGF)-beta 1. Transient transfection assays in macrophages showed that Ets-2 produced an increase in NOS2 promoter activity, whereas the induction by Ets-1 was modest and NERF2 had no effect. Elk-3 (Net/Erp/Sap-2a) markedly repressed NOS2 promoter activity in a dose-dependent fashion, and overexpression of Elk-3 blunted the induction of endogenous NOS2 message. Mutation of the Net inhibitory domain of Elk-3, but not the C-terminal-binding protein interaction domain, partially alleviated this repressive effect. We also found that deletion of the Ets domain of Elk-3 completely abolished its repressive effect on the NOS2 promoter. LPS administration to macrophages led to a dose-dependent decrease in endogenous Elk-3 mRNA levels, and this decrease in Elk-3 preceded the induction of NOS2 mRNA. In a mouse model of endotoxemia, the expression of Elk-3 in kidney, lung, and heart was significantly down-regulated after systemic administration of LPS, and this down-regulation also preceded NOS2 induction. Moreover, TGF-beta 1 significantly increased endogenous Elk-3 mRNA levels that had been down-regulated by LPS in macrophages. This increase in Elk-3 correlated with a TGF-beta 1-induced down-regulation of NOS2. Taken together, our data suggest that Elk-3 is a strong repressor of NOS2 promoter activity and mRNA levels and that endogenous expression of Elk-3 inversely correlates with NOS2. Thus, Elk-3 may serve as an important mediator of NOS2 gene expression.

Rapid, transient, and dose-dependent expression of Hsp70 messenger RNA in the rat brain after morphine treatment

PubMed Central

Ammon-Treiber, Susanne; Grecksch, Gisela; Stumm, Ralf; Riechert, Uta; Tischmeyer, Helga; Reichenauer, Anke; Höllt, Volker

2004-01-01

Induction of Hsp70 in the brain has been reported after intake of drugs of abuse like amphetamine and lysergic acid diethylamide. In this investigation, gene expression of Hsp70 and other heat shock genes in the rat brain was studied in response to morphine. Twenty milligrams per kilogram morphine intraperitoneally resulted in a marked induction of Hsp70 messenger RNA (mRNA) expression in the frontal cortex with a maximum increase of 13.2-fold after 2 hours. A moderate increase of Hsp27 mRNA expression (6.7-fold) could be observed after 4 hours, whereas mRNA expression of Hsp90 and of the constitutive Hsc70 did not exceed a mean factor of 1.8-fold during the 24 hours interval. The increase in Hsp70 mRNA was dose dependent, showing a significant elevation after doses ranging from 10 to 50 mg/kg morphine. In situ hybridization revealed enhanced Hsp70 mRNA expression mainly in cortical areas, in the hippocampus, in the paraventricular and supraoptic nuclei of the hypothalamus, in the locus coeruleus, as well in the pineal body. The double in situ hybridization technique revealed increased Hsp70 mRNA expression mainly in VGLUT1-positive neurons and to a lesser extent in olig1-positive oligodendroglia. Immunohistochemistry revealed a marked increase of Hsp70 protein in neuronal cells and blood vessels after 12 hours. In contrast to animal experiments, morphine did not increase Hsp70 mRNA expression in vitro in μ-opioid receptor (MOR1)–expressing human embryonic kidney 293 cells, suggesting no direct MOR1-mediated cellular effect. To exclude a body temperature–related morphine effect on Hsp70 mRNA expression, the temperature was recorded. Five to 20 mg/kg resulted in hyperthermia (maximum 40.6°), whereas a high dose (50 mg/kg) that produced the highest mRNA induction, showed a clear hypothermia (minimum 37.2°C). These findings argue against the possibility that Hsp70 induction by morphine is caused by its effect on body temperature. It may be speculated that increased expression of Hsp70 after morphine application protects brain structures against potentially hazardous effects of opiates. PMID:15497504

Overexpression of cerebral and hepatic cytochrome P450s alters behavioral activity of rat offspring following prenatal exposure to lindane

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johri, Ashu; Yadav, Sanjay; Dhawan, Alok

2007-12-15

Oral administration of different doses (0.0625, 0.125 or 0.25 mg/kg corresponding to 1/1400th, 1/700th or 1/350th of LD{sub 50}) of lindane to the pregnant Wistar rats from gestation days 5 to 21 were found to produce a dose-dependent increase in the activity of cytochrome P450 (CYP)-dependent 7-ethoxyresorufin-O-deethylase (EROD), 7-pentoxyresorufin-O-dealkylase (PROD) and N-nitrosodimethylamine demethylase (NDMA-d) in brain and liver of offspring postnatally at 3 weeks. The increase in the activity of CYP monooxygenases was found to be associated with the increase in the mRNA and protein expression of xenobiotic metabolizing CYP1A, 2B and 2E1 isoenzymes in the brain and liver ofmore » offspring. Dose-dependent alterations in the parameters of spontaneous locomotor activity in the offspring postnatally at 3 weeks have suggested that increase in CYP activity may possibly lead to the formation of metabolites to the levels that may be sufficient to alter the behavioral activity of the offspring. Interestingly, the inductive effect on cerebral and hepatic CYPs was found to persist postnatally up to 6 weeks in the offspring at the relatively higher doses (0.125 and 0.25 mg/kg) of lindane and up to 9 weeks at the highest dose (0.25 mg/kg), though the magnitude of induction was less than that observed at 3 weeks. Alterations in the parameters of spontaneous locomotor activity in the offspring postnatally at 6 and 9 weeks, though significant only in the offspring at 3 and 6-week of age, have further indicated that due to the reduced activity of the CYPs during the ontogeny, lindane and its metabolites may not be effectively cleared from the brain. The data suggest that low dose prenatal exposure to the pesticide has the potential to produce overexpression of xenobiotic metabolizing CYPs in brain and liver of the offspring which may account for the behavioral changes observed in the offspring.« less

Development of HSPA1A promoter-driven luciferase reporter gene assays in human cells for assessing the oxidative damage induced by silver nanoparticles.

PubMed

Xin, Lili; Wang, Jianshu; Zhang, Leshuai W; Che, Bizhong; Dong, Guangzhu; Fan, Guoqiang; Cheng, Kaiming

2016-08-01

The exponential increase in the total number of engineered nanoparticles in consumer products requires novel tools for rapid and cost-effective toxicology screening. In order to assess the oxidative damage induced by nanoparticles, toxicity test systems based on a human HSPA1A promoter-driven luciferase reporter in HepG2, LO2, A549, and HBE cells were established. After treated with heat shock and a group of silver nanoparticles (AgNPs) with different primary particle sizes, the cell viability, oxidative damage, and luciferase activity were determined. The time-dependent Ag(+) ions release from AgNPs in cell medium was also evaluated. Our results showed that heat shock produced a strong time-dependent induction of relative luciferase activity in the four luciferase reporter cells. Surprisingly, at 4h of recovery, the relative luciferase activity was >98× the control level in HepG2-luciferase cells. Exposure to different sizes of AgNPs resulted in activation of the HSPA1A promoter in a dose-dependent manner, even at low cytotoxic or non-cytotoxic doses. The smaller (5nm) AgNPs were more potent in luciferase induction than the larger (50 and 75nm) AgNPs. These results were generally in accordance with the oxidative damage indicated by malondialdehyde concentration, reactive oxygen species induction and glutathione depletion, and Ag(+) ions release in cell medium. Compared with the other three luciferase reporter cells, the luciferase signal in HepG2-luciferase cells is obviously more sensitive and stable. We conclude that the luciferase reporter cells, especially the HepG2-luciferase cells, could provide a valuable tool for rapid screening of the oxidative damage induced by AgNPs. Copyright © 2016 Elsevier Inc. All rights reserved.

Apoptotic and free radical scavenging properties of the methanolic extract of Gentianella alborosea.

PubMed

Acero, Nuria; Llinares, Francisco; Galán de Mera, Antonio; Oltra, Beatriz; Muñoz-Mingarro, Dolores

2006-09-01

Gentianella alborosea ("Hercampure") is a Peruvian species used in folk medicine for the treatment of a variety of health disorders. We tested the free radical scavenging (DPPH) and induction of apoptosis on a human uterus tumor cell line (HeLa) by its methanolic extract. The results showed a noticeable radical scavenging activity and a dose-dependent apoptotic effect.

Effects of aqueous, methanolic and chloroform extracts of rhizome and aerial parts of Valeriana officinalis L. on naloxone-induced jumping in morphine-dependent mice.

PubMed

Sharifzadeh, Mohammad; Hadjiakhoondi, Abbas; Khanavi, Mahnaz; Susanabadi, Maryam

2006-06-01

In the present study, the effects of rhizomes and aerial parts extracts of Valeriana officinalis L. on morphine dependence in mice have been investigated. Animals were treated subcutaneously with morphine (50, 50 and 75 mg/kg) three times daily (10 am, 1 pm and 4 pm) for 3 days, and a last dose of morphine (50 mg/kg) was administered on the fourth day. Withdrawal syndrome (jumping) was precipitated by naloxone (5 mg/kg) which was administered intraperitoneally 2 hours after the last dose of morphine. To study the effects of the aqueous, methanolic and chloroform extracts of both aerial parts and rhizome of the V. officinalis L. on naloxone-induced jumping in morphine-dependent animals, 10 injections of morphine (three administrations each day) for dependence and a dose of 5 mg/kg of naloxone for withdrawal induction were employed. Intraperitoneal injection of different doses (1, 5, 25 and 50 mg/kg) of aqueous, methanolic and chloroform extracts of the rhizome of V. officinalis L. 60 minutes before naloxone injection decreased the jumping response dose-dependently. Pre-treatment of animals with different doses (1, 5, 25, 50 and 100 mg/kg) of aqueous and methanolic extracts of aerial parts of V. officinalis L. 60 minutes before naloxone injection caused a significant decrease on naloxone-induced jumping. The chloroform extract of the aerial parts of V. officinalis L. did not show any significant changes on jumping response in morphine-dependent animals. It is concluded that the extracts of V. officinalis L. could affect morphine withdrawal syndrome via possible interactions with inhibitory neurotransmitters in nervous system.

Regiospecific Synthesis of Ring A Fused Withaferin A Isoxazoline Analogues: Induction of Premature Senescence by W-2b in Proliferating Cancer Cells.

PubMed

Rasool, Faheem; Nayak, Debasis; Katoch, Archana; Faheem, Mir Mohd; Yousuf, Syed Khalid; Hussain, Nazar; Belawal, Chetan; Satti, N K; Goswami, Anindya; Mukherjee, Debaraj

2017-10-23

Induction of premature senescence represents a novel functional strategy to curb the uncontrolled proliferation of malignant cancer cells. This study unveils the regiospecific synthesis of novel isoxazoline derivatives condensed to ring A of medicinal plant product Withaferin-A. Intriguingly, the cis fused products with β-oriented hydrogen exhibited excellent cytotoxic activities against proliferating human breast cancer MCF7 and colorectal cancer HCT-116 cells. The most potent derivative W-2b triggered premature senescence along with increase in senescence-associated β-galactosidase activity, G2/M cell cycle arrest, and induction of senescence-specific marker p21 Waf1/Cip1 at its sub-toxic concentration. W-2b conferred a robust increase in phosphorylation of mammalian checkpoint kinase-2 (Chk2) in cancer cells in a dose-dependent manner. Silencing of endogenous Chk2 by siRNA divulged that the amplification of p21 expression and senescence by W-2b was Chk2-dependent. Chk2 activation (either by ectopic overexpression or through treatment with W-2b) suppressed NM23-H1 signaling axis involved in cancer cell proliferation. Finally, W-2b showed excellent in vivo efficacy with 83.8% inhibition of tumor growth at a dose of 25 mg/kg, b.w. in mouse mammary carcinoma model. Our study claims that W-2b could be a potential candidate to limit aberrant cellular proliferation rendering promising improvement in the treatment regime in cancer patients.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Havarinasab, S.; Hultman, P.

Inorganic mercury may aggravate murine systemic autoimmune diseases which are either spontaneous (genetically determined) or induced by non-genetic mechanisms. Organic mercury species, the dominating form of mercury exposure in the human population, have not been examined in this respect. Therefore, ethyl mercury in the form of thimerosal, a preservative recently debated as a possible health hazard when present in vaccines, was administered in a dose of 0.156-5 mg/L drinking water to female (NZB x NZW)F1 (ZBWF1) mice. These mice develop an age-dependent spontaneous systemic autoimmune disease with high mortality primarily due to immune-complex (IC) glomerulonephritis. Five mg thimerosal/L drinking watermore » (295 {mu}g Hg/kg body weight (bw)/day) for 7 weeks induced glomerular, mesangial and systemic vessel wall IC deposits and antinuclear antibodies (ANA) which were not present in the untreated controls. After 22-25 weeks, the higher doses of thimerosal had shifted the localization of the spontaneously developing renal glomerular IC deposits from the capillary wall position seen in controls to the mesangium. The altered localization was associated with less severe histological kidney damage, less proteinuria, and reduced mortality. The effect was dose-dependent, lower doses having no effect compared with the untreated controls. A different effect of thimerosal treatment was induction of renal and splenic vessel walls IC deposits. Renal vessel wall deposits occurred at a dose of 0.313-5 mg thimerosal/L (18-295 {mu}g Hg/kg bw/day), while splenic vessel wall deposits developed also in mice given the lowest dose of thimerosal, 0.156 mg/L (9 {mu}g Hg/kg bw/day). The latter dose is 3- and 15-fold lower than the dose of Hg required to induce vessel wall IC deposits in genetically susceptible H-2 {sup s} mice by HgCl{sub 2} and thimerosal, respectively. Further studies on the exact conditions needed for induction of systemic IC deposits by low-dose organic mercurials in autoimmune-prone individuals, as well as the potential effect of these deposits on the vessel walls, are warranted.« less

Cancer risk estimates from radiation therapy for heterotopic ossification prophylaxis after total hip arthroplasty.

PubMed

Mazonakis, Michalis; Berris, Theoharris; Lyraraki, Efrossyni; Damilakis, John

2013-10-01

Heterotopic ossification (HO) is a frequent complication following total hip arthroplasty. This study was conducted to calculate the radiation dose to organs-at-risk and estimate the probability of cancer induction from radiotherapy for HO prophylaxis. Hip irradiation for HO with a 6 MV photon beam was simulated with the aid of a Monte Carlo model. A realistic humanoid phantom representing an average adult patient was implemented in Monte Carlo environment for dosimetric calculations. The average out-of-field radiation dose to stomach, liver, lung, prostate, bladder, thyroid, breast, uterus, and ovary was calculated. The organ-equivalent-dose to colon, that was partly included within the treatment field, was also determined. Organ dose calculations were carried out using three different field sizes. The dependence of organ doses upon the block insertion into primary beam for shielding colon and prosthesis was investigated. The lifetime attributable risk for cancer development was estimated using organ, age, and gender-specific risk coefficients. For a typical target dose of 7 Gy, organ doses varied from 1.0 to 741.1 mGy by the field dimensions and organ location relative to the field edge. Blocked field irradiations resulted in a dose range of 1.4-146.3 mGy. The most probable detriment from open field treatment of male patients was colon cancer with a high risk of 564.3 × 10(-5) to 837.4 × 10(-5) depending upon the organ dose magnitude and the patient's age. The corresponding colon cancer risk for female patients was (372.2-541.0) × 10(-5). The probability of bladder cancer development was more than 113.7 × 10(-5) and 110.3 × 10(-5) for males and females, respectively. The cancer risk range to other individual organs was reduced to (0.003-68.5) × 10(-5). The risk for cancer induction from radiation therapy for HO prophylaxis after total hip arthroplasty varies considerably by the treatment parameters, organ site in respect to treatment volume and patient's gender and age. The presented risk estimates may be useful in the follow-up studies of irradiated patients.

Induction of labor using prostaglandin E2 (PGE2) vaginal gel in triacetin base. An efficacy study comparing two dosage regimens.

PubMed

Seeras, R C; Olatunbosun, O A; Pierson, R A; Turnell, R W

1995-01-01

To compare two dosage regimens for the administration of vaginal prostaglandin gel in triacetin base for induction of labor. Seventy subjects planned for elective induction of labor at term were randomized to treatment with PGE2 vaginal gel every 6 or 12 hours. The 6-hourly group received an initial dose of 1 mg, followed by 2 mg at 6 hour intervals for a maximum of two additional doses if not in active labor. The 12-hourly group had an initial dose of 2 mg followed by two additional doses at 12 hour intervals if not in active labor. Successful induction rate was higher in the 12-hourly as compared to 6-hourly gel regimen (100% vs. 91%, P > 0.05). Twelve hours after the initial dose, delivery occurred in 34% delivery had occurred in 57% and 37% respectively (P < 0.01). We found no difference in the induction-active labor interval (P > 0.05), and the induction-delivery interval (P > 0.05) between the two groups. Active labor followed a single dose of gel in 66% of the 12-hourly group compared to 40% of the 6-hourly group (P < 0.01). Syntocinon augmentation was needed in 6% of subjects in the 12-hourly group as compared to 26% in the 6-hourly group (P < 0.01). The cesarean section rate was similar in both groups. Uterine hyperstimulation occurred less frequently in the 12-hourly group (P < 0.05). The perinatal outcome was similar in both groups. The 12-hourly regimen was more effective than the 6-hourly regimen in initiating labor. The majority of the subjects in the 12 hourly group achieved labor following a single dose of gel. Induction delivery interval, however, was similar in both groups.

The effect of ketamine on optical and electrical characteristics of spreading depolarizations in gyrencephalic swine cortex.

PubMed

Sánchez-Porras, Renán; Santos, Edgar; Schöll, Michael; Stock, Christian; Zheng, Zelong; Schiebel, Patrick; Orakcioglu, Berk; Unterberg, Andreas W; Sakowitz, Oliver W

2014-09-01

Spreading depolarization (SD) is a wave of mass neuronal and glial depolarization that propagates across the cerebral cortex and has been implicated in the pathophysiology of brain injury states and migraine with aura. Analgesics and sedatives seem to have a significant effect on SD modulation. Studies have shown that ketamine, an NMDA receptor blocker, has the capacity to influence SD occurrence. The aim of this study was to analyze the dose-dependent effect of ketamine on SD susceptibility through electrocorticography (ECoG) and intrinsic optical signal (IOS) imaging in a gyrencephalic brain. Ketamine in a low-dose infusion (2 mg/kg/h) decreases SD spread and had an effect on the amplitude of SD deflections, as well as on duration, and speed. Moreover, during ketamine infusion at this dose, there was a sustained decrease in the hyperemic response following SD. However, a high-dose infusion (4 mg/kg/h) of ketamine inhibited SD induction and expansion. Furthermore, a high-dose bolus (4 mg/kg), 1 min after stimulation, blocked SD propagation abruptly within 1-2 min, and hindered SD induction and expansion for the following 15-30 min. The results suggest that ketamine may be therapeutically beneficial in preventing SDs. Nonetheless, an adequate dosage and way of administration should be considered and established for human use. Copyright © 2014 Elsevier Ltd. All rights reserved.

Human Primary Keratinocytes as a Tool for the Analysis of Caspase-1-Dependent Unconventional Protein Secretion.

PubMed

Strittmatter, Gerhard E; Garstkiewicz, Martha; Sand, Jennifer; Grossi, Serena; Beer, Hans-Dietmar

2016-01-01

Inflammasomes comprise a group of protein complexes, which activate the protease caspase-1 upon sensing a variety of stress factors. Active caspase-1 in turn cleaves and thereby activates the pro-inflammatory cytokines prointerleukin (IL)-1β and -18, and induces unconventional protein secretion (UPS) of mature IL-1β, IL-18, as well as of many other proteins involved in and required for induction of inflammation. Human primary keratinocytes (HPKs) represent epithelial cells able to activate caspase-1 in an inflammasome-dependent manner upon irradiation with a physiological dose of ultraviolet B (UVB) light. Here, we describe the isolation of keratinocytes from human skin, their cultivation, and induction of caspase-1-dependent UPS upon UVB irradiation as well as its siRNA- and chemical-mediated inhibition. In contrast to inflammasome activation of professional immune cells, UVB-irradiated HPKs represent a robust and physiological cell culture system for the analysis of UPS induced by active caspase-1.

The Biological Effectiveness of Four Energies of Neon Ions for the Induction of Chromosome Damage in Human Lymphocytes

NASA Technical Reports Server (NTRS)

George, Kerry; Hada, Megumi; Cucinotta, F. A.

2011-01-01

Chromosomal aberrations were measured in human peripheral blood lymphocytes after in vitro exposure to neon ions at energies of 64, 89, 142, or 267. The corresponding LET values for these energies of neon ranged from 38-103 keV/micrometers and doses delivered were in the 10 to 80 cGy range. Chromosome exchanges were assessed in metaphase and G2 phase cells at first division after exposure using fluorescence in situ hybridization (FISH) with whole chromosome probes and dose response curves were generated for different types of chromosomal exchanges. The yields of total chromosome exchanges were similar for the 64, 89, and 142 MeV exposures, whereas the 267 MeV/u neon with LET of 38 keV/micrometers produced about half as many exchanges per unit dose. The induction of complex type chromosome exchanges (exchanges involving three or more breaks and two or more chromosomes) showed a clear LET dependence for all energies. The ratio of simple to complex type exchanges increased with LET from 18 to 51%. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose response curve for chromosome damage with respect to gamma-rays. The RBE(sub max) values for total chromosome exchanges for the 64 MeV/u was around 30.

[Drug dependence test on a cerebral insufficiency improver, aniracetam].

PubMed

Kuwahara, A; Kubota, A; Hakkei, M; Nakamura, K

1987-01-01

Aniracetam, 1-p-anisoyl-2-pyrrolidinone, is known to be a nootropic or cognitive activator. Aniracetam protects against memory and learning deficits without causing effects on motor function and the autonomic nervous system. A drug dependence study on aniracetam utilizing the intragastric route of administration was performed in male cynomolgus monkeys. The behavioral observation test after acute administration revealed that aniracetam at the dose of 25-400 mg/kg did not change the gross behavior. In the self-administration initiation test, animals were exposed to two or three unit doses of aniracetam and references for a total available period of 7 weeks. Aniracetam at the dose of 25, 50 and 75 mg/kg/injection did not initiate self-administration in the respective group of 4, 4 and 2 animals. In the study with d-methamphetamine hydrochloride at the dose of 0.1 mg/kg/injection, 1 out of 4 animals started to consistently self-administer the drug. Self-administration of cocaine hydrochloride at the dose of 10 mg/kg/injection was confirmed in 3 out of 5 animals, and these 3 animals died from overdosing later. In the physical dependence direct induction test, animals received aniracetam (50 mg/kg) and sodium pentobarbital (25 mg/kg: the dose inducing intermediate CNS depression) intragastrically twice a day for 31 consecutive days. Abrupt withdrawal of aniracetam did not elicit abstinent signs (including changes in appetite and body weight) in all 6 animals, whereas withdrawal of pentobarbital produced typical abstinent behavioral signs and decreases in appetite and body weight. In conclusion, aniracetam was confirmed to develop neither physical dependence nor psychic dependence in cynomolgus monkeys.

Comparative Analysis of the Relationship between Trichloroethylene Metabolism and Tissue-Specific Toxicity among Inbred Mouse Strains: Kidney Effects

PubMed Central

Yoo, Hong Sik; Bradford, Blair U.; Kosyk, Oksana; Uehara, Takeki; Shymonyak, Svitlana; Collins, Leonard B.; Bodnar, Wanda M.; Ball, Louise M.; Gold, Avram; Rusyn, Ivan

2014-01-01

Trichloroethylene (TCE) is a well-known environmental and occupational toxicant that is classified as carcinogenic to humans based on the epidemiological evidence of an association with higher risk of renal cell carcinoma. A number of scientific issues critical for assessing human health risks from TCE remain unresolved, such as the amount of kidney-toxic glutathione conjugation metabolites formed, inter-species and -individual differences, and the mode of action for kidney carcinogenicity. We hypothesized that TCE metabolite levels in the kidney are associated with kidney-specific toxicity. Oral dosing with TCE was conducted in sub-acute (600 mg/kg/d; 5 days; 7 inbred mouse strains) and sub-chronic (100 or 400 mg/kg/d; 1, 2, or 4 weeks; 2 inbred mouse strains) designs. We evaluated the quantitative relationship between strain-, dose-, and time-dependent formation of TCE metabolites from cytochrome P450-mediated oxidation [trichloroacetic acid (TCA), dichloroacetic acid (DCA), and trichloroethanol] and glutathione conjugation [S-(1,2-dichlorovinyl)-L-cysteine and S-(1,2-dichlorovinyl)glutathione], and various kidney toxicity phenotypes. In sub-acute study, we observed inter-strain differences in TCE metabolite levels in the kidney. In addition, we found that in several strains kidney-specific effects of TCE included induction of peroxisome proliferator-marker genes Cyp4a10 and Acox1, increased cell proliferation, and expression of KIM-1, a marker of tubular damage and regeneration. In sub-chronic study, peroxisome proliferator-marker gene induction and kidney toxicity diminished while cell proliferative response was elevated in a dose-dependent manner in NZW/LacJ, but not C57BL/6J mice. Overall, we show that TCE metabolite levels in the kidney are associated with kidney-specific toxicity and that these effects are strain-dependent. PMID:25424545

A consistent two-mutation model of bone cancer for two data sets of radium-injected beagles.

PubMed

Bijwaard, H; Brugmans, M J P; Leenhouts, H P

2002-09-01

A two-mutation carcinogenesis model has been applied to model osteosarcoma incidence in two data sets of beagles injected with 226Ra. Taking age-specific retention into account, the following results have been obtained: (1) a consistent and well-fitting solution for all age and dose groups, (2) mutation rates that are linearly dependent on dose rate, with an exponential decrease for the second mutation at high dose rates, (3) a linear-quadratic dose-effect relationship, which indicates that care should be taken when extrapolating linearly, (4) highest cumulative incidences for injection at young adult age, and highest risks for injection doses of a few kBq kg(-1) at these ages, and (5) when scaled appropriately, the beagle model compares fairly well with a description for radium dial painters, suggesting that a consistent model description of bone cancer induction in beagles and humans may be possible.

Contact-dependent depletion of hydrogen peroxide by catalase is a novel mechanism of myeloid-derived suppressor cell induction operating in human hepatic stellate cells.

PubMed

Resheq, Yazid J; Li, Ka-Kit; Ward, Stephen T; Wilhelm, Annika; Garg, Abhilok; Curbishley, Stuart M; Blahova, Miroslava; Zimmermann, Henning W; Jitschin, Regina; Mougiakakos, Dimitrios; Mackensen, Andreas; Weston, Chris J; Adams, David H

2015-03-15

Myeloid-derived suppressor cells (MDSC) represent a unique cell population with distinct immunosuppressive properties that have been demonstrated to shape the outcome of malignant diseases. Recently, human hepatic stellate cells (HSC) have been reported to induce monocytic-MDSC from mature CD14(+) monocytes in a contact-dependent manner. We now report a novel and unexpected mechanism by which CD14(+)HLADR(low/-) suppressive cells are induced by catalase-mediated depletion of hydrogen peroxide (H2O2). Incubation of CD14(+) monocytes with catalase led to a significant induction of functional MDSC compared with media alone, and H2O2 levels inversely correlated with MDSC frequency (r = -0.6555, p < 0.05). Catalase was detected in primary HSC and a stromal cell line, and addition of the competitive catalase inhibitor hydroxylamine resulted in a dose-dependent impairment of MDSC induction and concomitant increase of H2O2 levels. The NADPH-oxidase subunit gp91 was significantly increased in catalase-induced MDSC as determined by quantitative PCR outlining the importance of oxidative burst for the induction of MDSC. These findings represent a so far unrecognized link between immunosuppression by MDSC and metabolism. Moreover, this mechanism potentially explains how stromal cells can induce a favorable immunological microenvironment in the context of tissue oxidative stress such as occurs during cancer therapy. Copyright © 2015 by The American Association of Immunologists, Inc.

Nano-targeted induction of dual ferroptotic mechanisms eradicates high-risk neuroblastoma.

PubMed

Hassannia, Behrouz; Wiernicki, Bartosz; Ingold, Irina; Qu, Feng; Van Herck, Simon; Tyurina, Yulia Y; Bayır, Hülya; Abhari, Behnaz A; Angeli, Jose Pedro Friedmann; Choi, Sze Men; Meul, Eline; Heyninck, Karen; Declerck, Ken; Chirumamilla, Chandra Sekhar; Lahtela-Kakkonen, Maija; Van Camp, Guy; Krysko, Dmitri V; Ekert, Paul G; Fulda, Simone; De Geest, Bruno G; Conrad, Marcus; Kagan, Valerian E; Berghe, Wim Vanden; Vandenabeele, Peter; Berghe, Tom Vanden

2018-06-25

High-risk neuroblastoma is a devastating malignancy with very limited therapeutic options. Here, we identify withaferin A (WA) as a natural ferroptosis-inducing agent in neuroblastoma, which acts through a novel double-edged mechanism. WA dose-dependently either activates the nuclear factor-like 2 pathway through targeting of Kelch-like ECH-associated protein 1 (noncanonical ferroptosis induction) or inactivates glutathione peroxidase 4 (canonical ferroptosis induction). Noncanonical ferroptosis induction is characterized by an increase in intracellular labile Fe(II) upon excessive activation of heme oxygenase-1, which is sufficient to induce ferroptosis. This double-edged mechanism might explain the superior efficacy of WA as compared with etoposide or cisplatin in killing a heterogeneous panel of high-risk neuroblastoma cells, and in suppressing the growth and relapse rate of neuroblastoma xenografts. Nano-targeting of WA allows systemic application and suppressed tumor growth due to an enhanced accumulation at the tumor site. Collectively, our data propose a novel therapeutic strategy to efficiently kill cancer cells by ferroptosis.

A Luciferase Reporter Gene Assay to Measure Ebola Virus Viral Protein 35-Associated Inhibition of Double-Stranded RNA-Stimulated, Retinoic Acid-Inducible Gene 1-Mediated Induction of Interferon β.

PubMed

Cannas, Valeria; Daino, Gian Luca; Corona, Angela; Esposito, Francesca; Tramontano, Enzo

2015-10-01

During Ebola virus (EBOV) infection, the type I interferon α/β (IFN-α/β) innate immune response is suppressed by EBOV viral protein 35 (VP35), a validated drug target. Identification of EBOV VP35 inhibitors requires a cellular system able to assess the VP35-based inhibitory functions of viral double-stranded RNA (dsRNA) IFN-β induction. We established a miniaturized luciferase gene reporter assay in A549 cells that measures IFN-β induction by viral dsRNA and is dose-dependently inhibited by VP35 expression. When compared to influenza A virus NS1 protein, EBOV VP35 showed improved inhibition of viral dsRNA-based IFN-β induction. This assay can be used to screen for EBOV VP35 inhibitors. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Synergistic Effects Induced by a Low Dose of Diesel Particulate Extract and Ultraviolet-A in Caenorhabditis elegans: DNA Damage-Triggered Germ Cell Apoptosis

PubMed Central

2015-01-01

Diesel exhaust has been classified as a potential carcinogen and is associated with various health effects. A previous study showed that the doses for manifesting the mutagenetic effects of diesel exhaust could be reduced when coexposed with ultraviolet-A (UVA) in a cellular system. However, the mechanisms underlying synergistic effects remain to be clarified, especially in an in vivo system. In the present study, using Caenorhabditis elegans (C. elegans) as an in vivo system we studied the synergistic effects of diesel particulate extract (DPE) plus UVA, and the underlying mechanisms were dissected genetically using related mutants. Our results demonstrated that though coexposure of wild type worms at young adult stage to low doses of DPE (20 μg/mL) plus UVA (0.2, 0.5, and 1.0 J/cm2) did not affect worm development (mitotic germ cells and brood size), it resulted in a significant induction of germ cell death. Using the strain of hus-1::gfp, distinct foci of HUS-1::GFP was observed in proliferating germ cells, indicating the DNA damage after worms were treated with DPE plus UVA. Moreover, the induction of germ cell death by DPE plus UVA was alleviated in single-gene loss-of-function mutations of core apoptotic, checkpoint HUS-1, CEP-1/p53, and MAPK dependent signaling pathways. Using a reactive oxygen species (ROS) probe, it was found that the production of ROS in worms coexposed to DPE plus UVA increased in a time-dependent manner. In addition, employing a singlet oxygen (1O2) trapping probe, 2,2,6,6-tetramethyl-4-piperidone, coupled with electron spin resonance analysis, we demonstrated the increased 1O2 production in worms coexposed to DPE plus UVA. These results indicated that UVA could enhance the apoptotic induction of DPE at low doses through a DNA damage-triggered pathway and that the production of ROS, especially 1O2, played a pivotal role in initiating the synergistic process. PMID:24841043

Multi-walled carbon nanotubes (NM401) induce ROS-mediated HPRT mutations in Chinese hamster lung fibroblasts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rubio, Laura; El Yamani, Naouale; Kazimirova, Alena

Although there is an important set of data showing potential genotoxic effects of nanomaterials (NMs) at the DNA (comet assay) and chromosome (micronucleus test) levels, few studies have been conducted to analyze their potential mutagenic effects at gene level. We have determined the ability of multi-walled carbon nanotubes (MWCNT, NM401), to induce mutations in the HPRT gene in Chinese hamster lung (V79) fibroblasts. NM401, characterized in the EU NanoGenotox project, were further studied within the EU Framework Programme Seven (FP7) project NANoREG. From the proliferation assay data we selected a dose-range of 0.12 to 12 µg/cm{sup 2} At these rangemore » we have been able to observe significant cellular uptake of MWCNT by using transmission electron microscopy (TEM), as well as a concentration-dependent induction of intracellular reactive oxygen species. In addition, a clear concentration-dependent increase in the induction of HPRT mutations was also observed. Data support a potential genotoxic/ carcinogenic risk associated with MWCNT exposure. - Highlights: • MWCNT were tested in V79 cells. • Cellular uptake of MWCNT was detected using TEM. • Intracellular ROS induction was observed after MWCNT exposure. • MWCNT induced a concentration-dependent increase of HPRT mutations.« less

Estimation of TiO₂ nanoparticle-induced genotoxicity persistence and possible chronic gastritis-induction in mice.

PubMed

Mohamed, Hanan Ramadan Hamad

2015-09-01

Titanium dioxide (TiO2) nanoparticles are widely used as a food additive and coloring agent in many consumer products however limited data is available on the nano-TiO2 induced genotoxicity persistence. Thus, this study investigated the persistence of nano-TiO2 induced genotoxicity and possible induction of chronic gastritis in mice. The mice were orally administered 5, 50 or 500 mg/kg body weight nano-TiO2 for five consecutive days, and then mice from each dosage group were sacrificed 24 h or one or two weeks after the last treatment. The administration of nano-TiO2 resulted in persistent apoptotic DNA fragmentation and mutations in p53 exons (5-8) as well as significant persistent elevations in malondialdehyde and nitric oxide levels and decreases in the reduced glutathione level and catalase activity compared with the control mice in a dose- and time-dependent manner. Necrosis and inflammation were evident upon histological examination. These findings could be attributed to the persistent accumulation of nano-TiO2 at the tested doses at all three time points. Based on these findings, we conclude that the administration of nano-TiO2, even at low doses, leads to persistent accumulation of nano-TiO2 in mice, resulting in persistent inflammation, apoptosis and oxidative stress, ultimately leading to the induction of chronic gastritis. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Randomised, Double-blind, Placebo-controlled Trial of Trichuris suis ova in Active Crohn's Disease.

PubMed

Schölmerich, Jürgen; Fellermann, Klaus; Seibold, Frank W; Rogler, Gerhard; Langhorst, Jost; Howaldt, Stefanie; Novacek, Gottfried; Petersen, Andreas Munk; Bachmann, Oliver; Matthes, Harald; Hesselbarth, Norbert; Teich, Niels; Wehkamp, Jan; Klaus, Jochen; Ott, Claudia; Dilger, Karin; Greinwald, Roland; Mueller, Ralph

2017-04-01

To investigate the efficacy and safety of three different dosages of embryonated, viable eggs of Trichuris suis [TSO] versus placebo for induction of remission in mildly-to-moderately active ileocolonic, uncomplicated Crohn's disease [CD]. Adults with active CD [n = 252] randomly received six fortnightly doses of 250, 2500, or 7500 TSO/15 ml suspension/day [TSO 250, TSO 2500, TSO 7500], or 15 ml placebo solution/day, in a double-blind fashion, with 4 weeks' follow-up. Primary endpoint was the rate of clinical remission [Crohn's Disease Activity Index [CDAI] < 150] at end of treatment, ie at Week 12 or withdrawal. Secondary endpoints included the course of clinical remission, rate of clinical response, change in CDAI, change in markers of inflammation, mucosal healing, and Physician's Global Assessment. Clinical remission at Week 12 occurred in 38.5%, 35.2%, and 47.2% of TSO 250, TSO 2500, and TSO 7500 patients, respectively, and in 42.9% of placebo recipients. TSO induced a dose-dependent immunological response. There was no response regarding laboratory markers of inflammation. Other secondary efficacy variables also showed no advantage of TSO over placebo for treatment of active CD. Administration of TSO did not result in any serious adverse drug reaction. Review of non-serious suspected adverse drug reactions following TSO did not reveal any safety concerns. Administration of 250-7500 TSO fortnightly over 12 weeks was safe and showed a dose-dependent immunological response, but no TSO dose showed a clinically relevant effect over placebo for induction of clinical remission or response in mildly-to-moderately active, ileocolonic CD. © European Crohn’s and Colitis Organistion (ECCO) 2016.

Dose-response and relative biological effectiveness of fast neutrons: induction of apoptosis and inhibition of neurogenesis in the hippocampus of adult mice.

PubMed

Yang, Miyoung; Kim, Joong-Sun; Song, Myoung-Sub; Kim, Jong-Choon; Shin, Taekyun; Lee, Seung-Sook; Kim, Sung-Ho; Moon, Changjong

2010-06-01

Our study compared the effects of high linear energy transfer (LET) fast neutrons on the induction of apoptosis and reduction of neurogenesis in the hippocampus of adult ICR mice with those of low-LET (60)Co gamma-rays, to evaluate the relative biological effectiveness (RBE) of fast neutrons in the adult hippocampal dentate gyrus (DG). The mice were exposed to 35 MeV fast neutrons or (60)Co gamma-rays. We evaluated acutely the incidence of apoptosis and expression of Ki-67 (a protein marker for cell proliferation originally defined by the monoclonal antibody Kiel-67) and doublecortin (DCX: an immature progenitor neuron marker) in the hippocampus after a single whole-body irradiation. The number of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labelling (TUNEL)-positive apoptotic nuclei in the DG increased and both Ki-67- and DCX-positive cells declined in a dose-dependent pattern, with fast neutrons or gamma-rays. In the hippocampus, which showed an apoptosis frequency between 2 and 8 per DG, the RBE of fast neutrons was approximately 1.9. Additionally, the inhibitory effects of fast neutrons on the expression frequencies of Ki-67 (4-8) and DCX (8-32) were approximately 3.2 and 2.5 times, respectively, the effects of gamma-rays at the same dose. Increased apoptotic cell death and decreased neurogenesis in the hippocampal DG were seen in a dose-dependent pattern after exposure to fast neutrons and gamma-rays. In addition, the different rate of hippocampal neurogenesis between different radiation qualities may be an index of RBE.

Dose-dependent induction of cytochrome P450 (CYP) 3A4 and activation of pregnane X receptor by topiramate.

PubMed

Nallani, Srikanth C; Glauser, Tracy A; Hariparsad, Niresh; Setchell, Kenneth; Buckley, Donna J; Buckley, Arthur R; Desai, Pankaj B

2003-12-01

In clinical studies, topiramate (TPM) was shown to cause a dose-dependent increase in the clearance of ethinyl estradiol. We hypothesized that this interaction results from induction of hepatic cytochrome P450 (CYP) 3A4 by TPM. Accordingly, we investigated whether TPM induces CYP3A4 in primary human hepatocytes and activates the human pregnane X receptor (hPXR), a nuclear receptor that serves as a regulator of CYP3A4 transcription. Human hepatocytes were treated for 72 h with TPM (10, 25, 50, 100, 250, and 500 microM) and known inducers, phenobarbital (PB; 2 mM), and rifampicin (10 microM). The rate of testosterone 6beta-hydroxylation by hepatocytes served as a marker for CYP3A4 activity. The CYP3A4-specific protein and mRNA levels were determined by using Western and Northern blot analyses, respectively. The hPXR activation was assessed with cell-based reporter gene assay. Compared with controls, TPM (50-500 microM)-treated hepatocytes exhibited a considerable increase in the CYP3A4 activity (1. 6- to 8.2-fold), protein levels (4.6- to 17.3-fold), and mRNA levels (1.9- to 13.3-fold). Comparatively, rifampicin (10 microM) effected 14.5-, 25.3-, and a 20.3-fold increase in CYP3A4 activity, immunoreactive protein levels, and mRNA levels, respectively. TPM (50-500 microM) caused 1.3- to 3-fold activation of the hPXR, whereas rifampicin (10 microM) caused a 6-fold activation. The observed induction of CYP3A4 by TPM, especially at the higher concentrations, provides a potential mechanistic explanation of the reported increase in the ethinyl estradiol clearance by TPM. It also is suggestive of other potential interactions when high-dose TPM therapy is used.

Activation of cAMP-dependent signaling pathway induces mouse organic anion transporting polypeptide 2 expression.

PubMed

Chen, Chuan; Cheng, Xingguo; Dieter, Matthew Z; Tanaka, Yuji; Klaassen, Curtis D

2007-04-01

Rodent Oatp2 is a hepatic uptake transporter for such compounds as cardiac glycosides. In the present study, we found that fasting resulted in a 2-fold induction of Oatp2 expression in liver of mice. Because the cAMP-protein kinase A (PKA) signaling pathway is activated during fasting, the role of this pathway in Oatp2 induction during fasting was examined. In Hepa-1c1c7 cells, adenylyl cyclase activator forskolin as well as two cellular membrane-permeable cAMP analogs, dibutyryl cAMP and 8-bromo-cAMP, induced Oatp2 mRNA expression in a time- and dose-dependent manner. These three chemicals induced reporter gene activity in cells transfected with a luciferase reporter gene construct containing a 7.6-kilobase (kb) 5'-flanking region of mouse Oatp2. Transient transfection of cells with 5'-deletion constructs derived from the 7.6-kb Oatp2 promoter reporter gene construct, as well as 7.6-kb constructs in which a consensus cAMP response element (CRE) half-site CGTCA (-1808/-1804 bp) was mutated or deleted, confirms that this CRE site was required for the induction of luciferase activity by forskolin. Luciferase activity driven by the Oatp2 promoter containing this CRE site was induced in cells cotransfected with a plasmid encoding the protein kinase A catalytic subunit. Cotransfection of cells with a plasmid encoding the dominant-negative CRE binding protein (CREB) completely abolished the inducibility of the reporter gene activity by forskolin. In conclusion, induction of Oatp2 expression in liver of fasted mice may be caused by activation of the cAMP-dependent signaling pathway, with the CRE site (-1808/-1804) and CREB being the cis- and trans-acting factors mediating the induction, respectively.

Modulation of ethoxyresorufin O-deethylase and glutathione S-transferase activities in Nile tilapia (Oreochromis niloticus) by polycyclic aromatic hydrocarbons containing two to four rings: implications in biomonitoring aquatic pollution.

PubMed

Pathiratne, Asoka; Hemachandra, Chamini K

2010-08-01

Despite ubiquity of polycyclic aromatic hydrocarbons (PAHs) in the tropical environments, little information is available concerning responses of tropical fish to PAHs and associated toxicity. In the present study, effects of five PAHs containing two to four aromatic rings on hepatic CYP1A dependent ethoxyresorufin O-deethylase (EROD), glutathione S-transferase (GST) and serum sorbitol dehydrogenase (SDH) activities in Nile tilapia, a potential fish species for biomonitoring pollution in tropical waters, were evaluated. Results showed that EROD activities were induced by the PAHs containing four aromatic rings (pyrene and chrysene) in a dose dependent manner. However PAHs with two to three aromatic rings (naphthalene, phenanthrene and fluoranthene) caused no effect or inhibition of EROD activities depending on the dose and the duration. Fluoranthene was the most potent inhibitor. SDH results demonstrated that high doses of fluoranthene induced hepatic damage. GST activity was induced by the lowest dose of phenanthrene, fluoranthene and chrysene but high doses had no effect. The results indicate that induction of EROD enzyme in Nile tilapia is a useful biomarker of exposure to PAHs such as pyrene and chrysene. However EROD inhibiting PAHs such as fluoranthene in the natural environment may modulate the EROD inducing potential of other PAHs thereby influencing PAH exposure assessments.

Aqueous ethanol extract of the fruit of Xylopia aethiopica (Annonaceae) exhibits anti-anaphylactic and anti-inflammatory actions in mice.

PubMed

Obiri, David D; Osafo, Newman

2013-07-30

Xylopia aethiopica has been traditionally used in the form of the dried fruit decoction to treat bronchitis, asthma, arthritis and rheumatism in Ghana, Nigeria and Cameroon. Aim of the study is to evaluate the anti-anaphylactic and anti-inflammatory effects of a 70% aqueous ethanol extract of the fruits of Xylopia aethiopica. Systemic anaphylaxis was induced by the injection of either compound 48/80 or lipopolysaccharide, LPS and survival rates of mice monitored for 1 h or 7 days respectively while IgE-mediated anaphylaxis in a local allergic reaction was studied in the pinnal inflammation model in mice. Clonidine-induced catalepsy in mice was used to evaluate the indirect antihistamine effect of Xylopia aethiopica, XAE. The effects of XAE assessed on the maximal and total oedema responses in the carrageenan-induced paw oedema in mice was used to evaluate the anti-inflammatory action of the extract. Administered at 30, 100, 300 and 1000 mg kg(-1) p.o., XAE dose dependently suppressed compound 48/80-induced mouse systemic anaphylactic shock and offered 63% protection to mice against LPS-induced endotoxic shock at a dose of 300 mg kg(-1). In addition, the extract (30-300 mg kg(-1)) in a dose dependent manner significantly inhibited by 23-62% the mouse pinnal inflammation. Clonidine-induced catalepsy in mice was significantly suppressed in a dose and time dependent manner when administered both prophylactically and therapeutically. In the same doses, when administered before the induction of the mouse carrageenan-induced paw oedema, the mean maximal swelling attained during 6 h was reduced to 41.02±6.94%, 35.61±4.30%, and 29.09±4.90% of the inflamed control response respectively and total paw swellings induced over the 6 h were also dose-dependently and significantly suppressed to 74.84±14.84%, 63.95±9.37%, and 48.13±10.90% of the inflamed control response respectively. Administered after the induction of the carrageenan paw oedema the mean maximal swelling attained during 6 h was suppressed to 49.84±3.95%, 43.62±1.01%, and 35.97±1.34% of the inflamed control response respectively while the total paw swellings induced over the 6 h were also dose-dependently and significantly suppressed at 100 and 300 mg kg(-1) to 72.39±4.38% and 60.81±3.25% of the inflamed control response respectively. These findings suggest that XAE inhibits mast cell-dependent immediate allergic reactions and exhibit anti-inflammatory actions through the inhibition of histamine release from mast cells via stabilizing the cell membrane. Our results contribute towards validation of the traditional use of Xylopia aethiopica in the treatment of bronchitis, asthma, arthritis and rheumatism. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

[Cytogenetic effects of low dose radiation with different LET in human peripheral blood lymphocytes and possible mechanisms of their realization].

PubMed

Nasonova, E A; Shmakova, N L; Komova, O V; Mel'nikova, L A; Fadeeva, T A; Krasavin, E A

2006-01-01

The induction of chromosome damage by the exposure to low doses of gamma-(60)Co and accelerated carbon ions 12C in peripheral blood lymphocytes of different donors was investigated. The complex nonlinear dose-effect dependence at the range from 1 to 50-70 cGy was observed. At the doses of 1-5 cGy the cells show the highest radiosensitivity (hypersensitivity), mainly due to the chromatid-type aberration, which is typical to those spontaneously generated in the cell and believed not to be induced by the irradiation of unstimulated lymphocytes according to the classical theory of aberration formation. With the increasing dose the frequency of the aberrations decreases significantly, in some cases up to the control level. At the doses over 50-70 cGy the dose-effect curve becomes linear. The possible role of the oxidative stress, caused by radiation-induced increase in mitochondrial reactive oxigen species (ROS) release in the phenomenon of hypersensitivity (HS) at low doses is discussed as well as cytoprotective mechanisms causing the increased radioresistance at higher doses.

Chromatin- and temperature-dependent modulation of radiation-induced double-strand breaks.

PubMed

Elmroth, K; Nygren, J; Stenerlöw, B; Hultborn, R

2003-10-01

To investigate the influence of chromatin organization and scavenging capacity in relation to irradiation temperature on the induction of double-strand breaks (DSB) in structures derived from human diploid fibroblasts. Agarose plugs with different chromatin structures (intact cells+/-wortmannin, permeabilized cells with condensed chromatin, nucleoids and DNA) were prepared and irradiated with X-rays at 2 or 37 degrees C and lysed using two different lysis protocols (new ice-cold lysis or standard lysis at 37 degrees C). Induction of DSB was determined by constant-field gel electrophoresis. The dose-modifying factor (DMF(temp)) for irradiation at 37 compared with 2 degrees C was 0.92 in intact cells (i.e. more DSB induced at 2 degrees C), but gradually increased to 1.5 in permeabilized cells, 2.2 in nucleoids and 2.6 in naked DNA, suggesting a role of chromatin organization for temperature modulation of DNA damage. In addition, DMF(temp) was influenced by the presence of 0.1 M DMSO or 30 mM glutathione, but not by post-irradiation temperature. The protective effect of low temperature was correlated to the indirect effects of ionizing radiation and was not dependent on post-irradiation temperature. Reasons for a dose modifying factor <1 in intact cells are discussed.

Annatto Tocotrienol Induces a Cytotoxic Effect on Human Prostate Cancer PC3 Cells via the Simultaneous Inhibition of Src and Stat3.

PubMed

Sugahara, Ryosuke; Sato, Ayami; Uchida, Asuka; Shiozawa, Shinya; Sato, Chiaki; Virgona, Nantiga; Yano, Tomohiro

2015-01-01

Prostate cancer is one of the most frequently occurring cancers and often acquires the potential of androgen-independent growth as a malignant phenotype. Androgen-independent prostate cancer has severe chemoresistance towards conventional chemotherapeutic agents, so a new treatment approach is required for curing such prostate cancer. In this context, the present study was undertaken to check if annatto tocotrienol (main component δ-tocotrienol) could suppress cell growth in human prostate cancer (PC3, androgen-independent type) cells via the inhibition of Src and Stat3. The tocotrienol showed cytotoxic effects on PC3 cells in a dose-dependent manner, and the effect depended on G1 arrest in the cell cycle and subsequent induction of apoptosis. In a cytotoxic dose, the tocotrienol suppressed cellular growth via the simultaneous inhibition of Src and Stat3. Similarly, the treatment combination of both Src and Stat3 inhibitors induced cytotoxic effects in PC3 cells in an additive manner compared to each by itself. With respect to cell cycle regulation and the induction of apoptosis, the combination treatment showed a similar effect to that of the tocotrienol treatment. These results suggest that annatto tocotrienol effectively induces cytotoxicity in androgen-independent prostate cancer cells via the suppression of Src and Stat3.

Ionizing radiation induces O6-alkylguanine-DNA-alkyltransferase mRNA and activity in mouse tissues.

PubMed

Wilson, R E; Hoey, B; Margison, G P

1993-04-01

The effect of exposure to whole-body gamma-irradiation or fast electrons on O6-alkylguanine-DNA-alkyltransferase (ATase) activity and mRNA abundance has been examined in mice. In response to gamma-radiation, hepatic ATase activity was significantly raised in BDF1 mice 24 h post-irradiation, reaching a maximum of 2- to 3-fold at 36 h and beginning to decrease by 48-60 h. A small but consistently higher level of induction was achieved when mice were exposed using a low dose rate (0.015 Gy/min) compared to a high dose rate (0.5 Gy/min). ATase activity was also induced approximately 2-fold 48 h post-irradiation in brain, kidney, lung and spleen, with a greater induction again observed in response to the lower dose rate. In response to fast electrons from a linear accelerator hepatic ATase activity was also induced 2- to 3-fold 48 h post-irradiation in BDF1, BALB/c, C57Bl and DBA2 strains. Induction of ATase activity in livers of BDF1 mice was observed 48 h after a total single dose of 5 Gy gamma-radiation (2-fold), increasing to a slightly higher level at 15 Gy, but no induction was observed at doses of 2 Gy and below. Although a maximum 2- to 3-fold induction of ATase activity was observed, mRNA levels were induced 3- to 4-fold by 48 h after a dose of 15 Gy. Furthermore, significant increases in mRNA levels were detected at low doses (1-2 Gy) at which there was no apparent increase in ATase activity. This suggests that ionizing radiation increases ATase levels by a process involving transcriptional upregulation but that strong post-transcriptional and/or translational controls operate to limit induction of enzyme activity to 2- to 3-fold. This is the first report of an in vivo induction of ATase by ionizing radiation in a species other than the rat.

Severe palmar-plantar erythrodysesthesia and aplasia in an adult undergoing re-induction treatment with high-dose cytarabine for acute myelogenous leukemia: a possible drug interaction between posaconazole and cytarabine.

PubMed

Alzghari, Saeed K; Seago, Susan E; Cable, Christian T; Herrington, Jon D

2017-09-01

High-dose cytarabine is recommended for re-induction chemotherapy in patients less than 60 years of age with acute myelogenous leukemia. This case describes a patient receiving high-dose cytarabine for re-induction and subsequently developed tingling and numbness in her hands and feet followed by severe pain, swelling, and erythema consistent with a diagnosis of palmar-plantar erythrodysesthesia. Furthermore, the patient's hemoglobin, platelets, and neutrophils did not recover after over 30 days post high-dose cytarabine. The patient was concurrently receiving posaconazole for fungal prophylaxis which was initiated after the induction therapy. We speculate that posaconazole may inhibit the cytarabine efflux through P-glycoprotein inhibition leading to the patient's palmar-plantar erythrodysesthesia and subsequent aplasia. Future pharmacokinetic studies need to be conducted to ascertain if posaconazole does influence the pharmacokinetics of cytarabine.

TCDD, FICZ, and Other High Affinity AhR Ligands Dose-Dependently Determine the Fate of CD4+ T Cell Differentiation.

PubMed

Ehrlich, Allison K; Pennington, Jamie M; Bisson, William H; Kolluri, Siva K; Kerkvliet, Nancy I

2018-02-01

FICZ and TCDD, two high-affinity AhR ligands, are reported to have opposite effects on T cell differentiation with TCDD inducing regulatory T cells and FICZ inducing Th17 cells. This dichotomy has been attributed to ligand-intrinsic differences in AhR activation, although differences in sensitivity to metabolism complicate the issue. TCDD is resistant to AhR-induced metabolism and produces sustained AhR activation following a single dose in the μg/kg range, whereas FICZ is rapidly metabolized and AhR activation is transient. Nonetheless, prior studies comparing FICZ with TCDD have generally used the same 10-50 μg/kg dose range, and thus the two ligands would not equivalently activate AhR. We hypothesized that high-affinity AhR ligands can promote CD4+ T cell differentiation into both Th17 cells and Tregs, with fate depending on the extent and duration of AhR activation. We compared the immunosuppressive effects of TCDD and FICZ, along with two other rapidly metabolized ligands (ITE and 11-Cl-BBQ) in an acute alloresponse mouse model. The dose and timing of administration of each ligand was optimized for TCDD-equivalent Cyp1a1 induction. When optimized, all of the ligands suppressed the alloresponse in conjunction with the induction of Foxp3- Tr1 cells on day 2 and the expansion of natural Foxp3+ Tregs on day 10. In contrast, a low dose of FICZ induced transient expression of Cyp1a1 and did not induce Tregs or suppress the alloresponse but enhanced IL-17 production. Interestingly, low doses of the other ligands, including TCDD, also increased IL-17 production on day 10. These findings support the conclusion that the dose and the duration of AhR activation by high-affinity AhR ligands are the primary factors driving the fate of T cell differentiation. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Induction of genomic instability after an acute whole-body exposure of mice to 56Fe ions

NASA Astrophysics Data System (ADS)

Rithidech, Kanokporn Noy; Supanpaiboon, Wisa; Honikel, Louise; Whorton, Elbert B.

2009-10-01

The purpose of this study was to evaluate dose-response relationships for the in vivo induction of micronuclei (MN) as a measure of both initial radiation damage and the induction of genomic instability. These measurements were made in mouse blood erythrocytes as a function of radiation dose, radiation quality, time after irradiation, and the genetic background of exposed individuals. Blood samples were collected from two strains of mouse (CBA/CaJ and C57BL/6J) at different times up to 3 months following a whole-body exposure to various doses of 1 GeV/amu 56Fe ions (0, 0.1, 0.5 and 1.0 Gy, at the dose rate of a 1 Gy/min) or 137Cs gamma rays (0, 0.5, 1.0 and 3.0 Gy, at the dose rate of 0.72 Gy/min). Blood-smear slides were stained with acridine orange (AO). The frequencies of MN were measured in mature normochromatic-erythrocytes (MN-NCEs) and in immature polychromatic-erythrocytes (MN-PCEs). Effects of both types of radiation on erythropoiesis were also evaluated. As a measure of cell progression delay, a dose-dependent decrease in numbers of PCEs was observed at day 2 post-exposure in both strains, regardless of radiation quality. Subsequently, the levels of PCEs increased in all exposed mice, reaching control levels (or higher) by day 7 post-exposure. Further, at day 2 after the exposure, there was no increase in the frequency of MN-PCEs in CBA/CaJ mice exposed to 56Fe ions while the frequency of MN-PCEs elevated as a function of dose in the C57BL/6J mice. At day 4, there was no dose related increase in MN-NCEs in either strain of mouse exposed to 137Cs gamma rays. Additionally, at the early sacrifice times (days 2 and 4), 56Fe ions were slightly more effective (per unit dose) in inducing MN-NCEs than 137Cs gamma rays in CBA/CaJ mice. However, there was no increase in the frequency of MN-NCEs at late times after an acute exposure to either type of radiation. In contrast, both types of radiation induced increased MN-PCEs frequencies in irradiated CBA/CaJ mice, but not C57BL/6J mice, at late times post-exposure. This finding indicates the potential induction of genomic instability in hematopoietic cells of CBA/CaJ mice by both types of radiation. The finding also demonstrates the influence of genetic background on radiation-induced genomic instability in vivo.

Effects of conventional vs high-dose rocuronium on the QTc interval during anesthesia induction and intubation in patients undergoing coronary artery surgery: a randomized, double-blind, parallel trial

PubMed Central

Öztürk, T.; Ağdanlı, D.; Bayturan, Ö.; Çıkrıkcı, C.; Keleş, G.T.

2015-01-01

Myocardial ischemia, as well as the induction agents used in anesthesia, may cause corrected QT interval (QTc) prolongation. The objective of this randomized, double-blind trial was to determine the effects of high- vs conventional-dose bolus rocuronium on QTc duration and the incidence of dysrhythmias following anesthesia induction and intubation. Fifty patients about to undergo coronary artery surgery were randomly allocated to receive conventional-dose (0.6 mg/kg, group C, n=25) or high-dose (1.2 mg/kg, group H, n=25) rocuronium after induction with etomidate and fentanyl. QTc, heart rate, and mean arterial pressure were recorded before induction (T0), after induction (T1), after rocuronium (just before laryngoscopy; T2), 2 min after intubation (T3), and 5 min after intubation (T4). The occurrence of dysrhythmias was recorded. In both groups, QTc was significantly longer at T3 than at baseline [475 vs 429 ms in group C (P=0.001), and 459 vs 434 ms in group H (P=0.005)]. The incidence of dysrhythmias in group C (28%) and in group H (24%) was similar. The QTc after high-dose rocuronium was not significantly longer than after conventional-dose rocuronium in patients about to undergo coronary artery surgery who were induced with etomidate and fentanyl. In both groups, compared with baseline, QTc was most prolonged at 2 min after intubation, suggesting that QTc prolongation may be due to the nociceptive stimulus of intubation. PMID:25714880

Molecular, cellular, and genetic basis of radiosensitivity at low doses: a case of inducible repair?

PubMed

Skov, K A

1994-04-01

Many proteins are induced by ionizing radiation, and genes are activated. We still do not know which, if any, are responsible for IRR, or what leads to the adaptive response seen at still lower doses. Are these the same responses? Are they related to apoptosis, repair of potentially lethal damage and other responses? Does the cell have a whole battery of responses, depending on the dose? I suspect this is the case. Can the responses be explained more simply, as effects on regulators of cell cycle or induction of fidelity, or is there induction of repair? Are there still other explanations for the apparent protection? The initial slope of the survival curve which was addressed earlier (1) must take on new meaning given the hyperradiosensitive portion. Similarly, we may have to change our thinking with respect to the LQ description of survival data. It is not surprising that this workshop, held at such an early stage primarily to address the phenomenon of increased radioresistance, produced more questions than answers. Single-strand breaks may trigger resistance, but additional lesions or classes of damage may be relevant. Some physicists expect the damage caused to be linear with dose; the biologists suggest that the response is nonlinear (e.g. saturation of an enzyme, induction of repair, cell cycle effects) and there is room for biochemistry which could also vary with dose (e.g. consumption of a protector or a sensitizer). Some biophysicists would argue that the observed structures in survival curves might be explained by change in the target cross section such as a large change in DNA conformation caused by a very low dose. There is some reluctance in the radiobiology community to accept that cells may respond to ionizing radiation by inducing or activating protective mechanisms, although the cell exhibits defensive responses to many other detrimental stimuli. If "the heart of the matter is in the shape of the survival curve" as suggested by Dr. Elkind in his summary of the 1974 "low doses" conference (p. 385 in ref. 1), then we are fortunate indeed that there are now additional methods to attack the question directly of what is turned on or activated. It is anticipated that there will be many further developments within the year, to be presented at related sessions at larger meetings, and at a closely related meeting to be held in June 1994 in Montreal, entitled "Gene Induction and Adaptive Responses in Irradiated Cells: Mechanisms and Clinical Implications."

Immune tolerance: critical issues of factor dose, purity and treatment complications.

PubMed

DiMichele, D M

2006-12-01

The current practice of immune tolerance induction (ITI) therapy has been largely influenced by the results of small institutional studies and three large registries. However, many questions remain. Successful outcome predictors for ITI in haemophilia A have been suggested by the analyses of two of these registries. Among these predictors, factor VIII (FVIII) dose/dosing regimen remains a controversial outcome parameter, demonstrating a strong direct relationship to ITI success in the international registry and a weaker inverse relationship in the North American registry. There is an international multicentre prospective randomized trial underway to further study the role of FVIII dose in successful ITI induction in a good risk haemophilia A inhibitor patient cohort. FVIII purity also remains an unproved ITI outcome predictor. Institutional experience with von-Willebrand-factor-containing products has suggested its therapeutic advantage in both inhibitor development and eradication. The International ITI Study, although not designed to answer this particular question, may be able to determine an impact on outcome depending on the final distribution of investigator choice of product among the study subjects. Much less is known about the influence of factor IX (FIX) dose and purity on ITI success in haemophilia B. Importantly, nephrotic syndrome has been a major determinant of ITI failure in FIX inhibitor patients, particularly those with the allergic phenotype. Unfortunately, large prospective randomized trials in this group will not be feasible. Rather, we will have to rely on prospectively collected registry data to build our knowledge base of inhibitors and ITI in haemophilia B.

Efficacy of protocols for induction of chronic hyperthyroidism in male and female mice.

PubMed

Engels, Kathrin; Rakov, Helena; Zwanziger, Denise; Hönes, Georg Sebastian; Rehders, Maren; Brix, Klaudia; Köhrle, Josef; Möller, Lars Christian; Führer, Dagmar

2016-10-01

Protocols for induction of hyperthyroidism in mice are highly variable and mostly involve short-term thyroid hormone (TH) treatment. In addition, little is known about a possible influence of sex on experimental TH manipulation. Here we analyzed the efficacy of intraperitoneal vs. oral levothyroxine (T4) administration to induce chronic hyperthyroidism in male and female mice and asked which T4 dosing intervals are required to achieve stable organ thyrotoxicosis. T4 was administered intraperitoneally or orally over a period of 6/7 weeks. Assessment included monitoring of body weight, TH serum concentrations, and serial quantitative TH target gene expression analysis in liver and heart. Our results show that both intraperitoneal and oral T4 treatment are reliable methods for induction of chronic hyperthyroidism in mice. Thereby T4 injection intervals should not exceed 48 h and oral levothyroxine should be administered continuously during experiments and up to sacrifice to ensure a hyperthyroid organ state. Furthermore, we found a sex-dependent variation in levothyroxine-induced TH serum state, with significantly higher T4 concentrations in female mice, while expression of investigated classical TH responsive genes in liver and heart did not vary with animal's sex. In summary, our study shows that common approaches for rendering rodents thyrotoxic can also be used for induction of chronic hyperthyroidism in male and female mice. Thereby T4 dosing intervals are critical as are read-out parameters to verify a chronic thyrotoxic organ state.

Protein Kinase G facilitates EGFR-mediated cell death in MDA-MB-468 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jackson, Nicole M.; Ceresa, Brian P., E-mail: brian.ceresa@louisville.edu

The Epidermal Growth Factor Receptor (EGFR) is a transmembrane receptor tyrosine kinase with critical implications in cell proliferation, migration, wound healing and the regulation of apoptosis. However, the EGFR has been shown to be hyper-expressed in a number of human malignancies. The MDA-MB-468 metastatic breast cell line is one example of this. This particular cell line hyper-expresses the EGFR and undergoes EGFR-mediated apoptosis in response to EGF ligand. The goal of this study was to identify the kinases that could be potential intermediates for the EGFR-mediated induction of apoptosis intracellularly. After identifying Cyclic GMP-dependent Protein Kinase G (PKG) as amore » plausible intermediate, we wanted to determine the temporal relationship of these two proteins in the induction of apoptosis. We observed a dose-dependent decrease in MDA-MB-468 cell viability, which was co-incident with increased PKG activity as measured by VASPSer239 phosphorylation. In addition, we observed a dose dependent decrease in cell viability, as well as an increase in apoptosis, in response to two different PKG agonists, 8-Bromo-cGMP and 8-pCPT-cGMP. MDA-MB-468 cells with reduced PKG activity had attenuated EGFR-mediated apoptosis. These findings indicate that PKG does not induce cell death via transphosphorylation of the EGFR. Instead, PKG activity occurs following EGFR activation. Together, these data indicate PKG as an intermediary in EGFR-mediated cell death, likely via apoptotic pathway.« less

The Mechanism of Autoinduction of Methadone N-demethylation in Human Hepatocytes

PubMed Central

Campbell, Scott D.; Crafford, Amanda; Williamson, Brian L.; Kharasch, Evan D.

2013-01-01

Background There is considerable inter-and intraindividual variability in methadone metabolism and clearance. Methadone dosing is particularly challenging during initiation of therapy, due to time-dependent increases in hepatic clearance (autoinduction). Although methadone N-demethylation is catalyzed in vitro by cytochrome P4502B6 (CYP2B6) and CYP3A4, and clearance in vivo depends on CYP2B6, mechanism(s) of autoinduction are incompletely understood. In this investigation we determined mechanism(s) of methadone autoinduction using human hepatocytes. Methods Fresh human hepatocytes were exposed to 0.1-10 μM methadone for 72 hr. Cells were washed and methadone N-demethylation assessed. CYP2B6, CYP3A4, and CYP3A5 mRNA, protein expression (by gel-free high performance liquid chromatography-mass spectrometry) and catalytic activity (bupropion hydroxylation and alfentanil dealkylation for CYP2B6 and CYP3A4/5, respectively) were measured. Mechanisms of CYP induction were characterized using pregnane X receptor and constitutive androstane receptor reporter gene assays. Results Methadone (10 μM) increased methadone N-demethylation 2-fold, CYP2B6 and CYP3A4 mRNA 3-fold, and protein expression 2-fold. CYP3A5 mRNA was unchanged. CYP2B6 and CYP3A4/5 activities increased 2-fold. Induction by methadone enantiomers (R- vs S-methadone) did not differ. Induction was relatively weak compared with maximum induction by phenobarbital and rifampin. Lower methadone concentrations had smaller effects. Methadone was an agonist for the pregnane X receptor but not the constitutive androstane receptor. Conclusions Methadone caused concentration-dependent autoinduction of methadone N-demethylation in human hepatocytes, related to induction of CYP2B6 and CYP3A4 mRNA expression, protein expression, and catalytic activity. Induction was related to pregnane X receptor but not constitutive androstane receptor activation. These in vitro findings provide mechanistic insights into clinical autoinduction of methadone metabolism and clearance. PMID:23733841

Antioxidant, Antiproliferative, and Antiangiogenesis Effects of Polyphenol-Rich Seaweed (Sargassum muticum)

PubMed Central

Namvar, Farideh; Mohamad, Rosfarizan; Baharara, Javad; Zafar-Balanejad, Saeedeh; Fargahi, Fahimeh; Rahman, Heshu Sulaiman

2013-01-01

In the present study, we evaluated the effect of brown seaweeds Sargassum muticum methanolic extract (SMME), against MCF-7 and MDA-MB-231 breast cancer cell lines proliferation. This algae extract was also evaluated for reducing activity and total polyphenol content. The MTT assay results indicated that the extracts were cytotoxic against breast cancer cell lines in a dose-dependent manner, with IC50 of 22 μg/ml for MCF-7 and 55 μg/ml for MDA-MB-231 cell lines. The percentages of apoptotic MCF-7-treated cells increased from 13% to 67% by increasing the concentration of the SMME. The antiproliferative efficacy of this algal extract was positively correlated with the total polyphenol contents, suggesting a causal link related to extract content of phenolic acids. Cell cycle analysis showed a significant increase in the accumulation of SMME-treated cells at sub-G1 phase, indicating the induction of apoptosis by SMME. Further apoptosis induction was confirmed by Hoechst 33342 and AO/PI staining. Also SMME implanted in vivo into fertilized chicken eggs induced dose-related antiangiogenic activity in the chorioallantoic membrane (CAM). Our results imply a new insight on the novel function of Sargassum muticum polyphenol-rich seaweed in cancer research by induction of apoptosis, antioxidant, and antiangiogenesis effects. PMID:24078922

Bax and Bak are required for apoptosis induction by sulforaphane, a cruciferous vegetable-derived cancer chemopreventive agent.

PubMed

Choi, Sunga; Singh, Shivendra V

2005-03-01

Sulforaphane, a constituent of many edible cruciferous vegetables, including broccoli, effectively suppresses proliferation of cancer cells in culture and in vivo by causing apoptosis induction, but the sequence of events leading to cell death is poorly defined. Here, we show that multidomain proapoptotic Bcl-2 family members Bax and Bak play a critical role in apoptosis induction by sulforaphane. This conclusion is based on the following observations: (a) sulforaphane treatment caused a dose- and time-dependent increase in the protein levels of both Bax and Bak and conformational change and mitochondrial translocation of Bax in SV40-transformed mouse embryonic fibroblasts (MEF) derived from wild-type mice to trigger cytosolic release of apoptogenic molecules (cytochrome c and Smac/DIABLO), activation of caspase-9 and caspase-3, and ultimately cell death; (b) MEFs derived from Bax or Bak knockout mice resisted cell death by sulforaphane, and (c) MEFs derived from Bax and Bak double knockout mice exhibited even greater protection against sulforaphane-induced cytochrome c release, caspase activation, and apoptosis compared with wild-type or single knockout cells. Interestingly, sulforaphane treatment also caused a dose- and time-dependent increase in the protein level of Apaf-1 in wild-type, Bax-/-, and Bak-/- MEFs but not in double knockout, suggesting that Bax and Bak might regulate sulforaphane-mediated induction of Apaf-1 protein. A marked decline in the protein level of X-linked inhibitor of apoptosis on treatment with sulforaphane was also observed. Thus, it is reasonable to postulate that sulforaphane-induced apoptosis is amplified by a decrease in X-linked inhibitor of apoptosis level, which functions to block cell death by inhibiting activities of caspases. In conclusion, the results of the present study indicate that Bax and Bak proteins play a critical role in initiation of cell death by sulforaphane.

Cancer risk estimates from radiation therapy for heterotopic ossification prophylaxis after total hip arthroplasty

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mazonakis, Michalis; Berris, Theoharris; Damilakis, John

2013-10-15

Purpose: Heterotopic ossification (HO) is a frequent complication following total hip arthroplasty. This study was conducted to calculate the radiation dose to organs-at-risk and estimate the probability of cancer induction from radiotherapy for HO prophylaxis.Methods: Hip irradiation for HO with a 6 MV photon beam was simulated with the aid of a Monte Carlo model. A realistic humanoid phantom representing an average adult patient was implemented in Monte Carlo environment for dosimetric calculations. The average out-of-field radiation dose to stomach, liver, lung, prostate, bladder, thyroid, breast, uterus, and ovary was calculated. The organ-equivalent-dose to colon, that was partly included withinmore » the treatment field, was also determined. Organ dose calculations were carried out using three different field sizes. The dependence of organ doses upon the block insertion into primary beam for shielding colon and prosthesis was investigated. The lifetime attributable risk for cancer development was estimated using organ, age, and gender-specific risk coefficients.Results: For a typical target dose of 7 Gy, organ doses varied from 1.0 to 741.1 mGy by the field dimensions and organ location relative to the field edge. Blocked field irradiations resulted in a dose range of 1.4–146.3 mGy. The most probable detriment from open field treatment of male patients was colon cancer with a high risk of 564.3 × 10{sup −5} to 837.4 × 10{sup −5} depending upon the organ dose magnitude and the patient's age. The corresponding colon cancer risk for female patients was (372.2–541.0) × 10{sup −5}. The probability of bladder cancer development was more than 113.7 × 10{sup −5} and 110.3 × 10{sup −5} for males and females, respectively. The cancer risk range to other individual organs was reduced to (0.003–68.5) × 10{sup −5}.Conclusions: The risk for cancer induction from radiation therapy for HO prophylaxis after total hip arthroplasty varies considerably by the treatment parameters, organ site in respect to treatment volume and patient's gender and age. The presented risk estimates may be useful in the follow-up studies of irradiated patients.« less

Cognitive deficits in adult rats by lead intoxication are related with regional specific inhibition of cNOS.

PubMed

García-Arenas, Guadalupe; Ramírez-Amaya, Victor; Balderas, Israela; Sandoval, Jimena; Escobar, Martha L; Ríos, Camilo; Bermúdez-Rattoni, Federico

2004-02-04

It is well known that lead can affect several cognitive abilities in developing animals. In this work, we investigate the effects of different sub-chronic lead doses (0, 65, 125, 250 and 500 ppm of lead acetate in their drinking water for 14 days) in the performance of male adult rats in a water maze, cue maze and inhibitory avoidance tasks. We found that the acquisition of these tasks was not affected by lead, however, the highest dosage of lead (500 ppm) impaired memory consolidation in spatial and inhibitory avoidance tasks, but not in cue maze task while the 250 ppm dose only affected retrieval of spatial memory. Additionally, hippocampal long-term potentiation (LTP) induction in the perforant path after exposing adult rats to different doses of lead was studied. LTP induction was affected in a dose-dependent manner, and treatments of 250 and 500 ppm completely blocked LTP. We investigated the effects of lead intoxication on the activity of constitutive nitric oxide synthase (cNOS) in different brain regions of adult animals. The activity of cNOS was significantly inhibited in the hippocampus and cerebellum but not in the frontal cortex and brain stem, although lead had accumulated in all brain regions. These results suggest that lead intoxication can impair memory in adult animals and this impairment might be related with region-specific effects on cNOS activity.

Exposure to low UVA doses increases KatA and KatB catalase activities, and confers cross-protection against subsequent oxidative injuries in Pseudomonas aeruginosa.

PubMed

Pezzoni, Magdalena; Tribelli, Paula M; Pizarro, Ramón A; López, Nancy I; Costa, Cristina S

2016-05-01

Solar UVA radiation is one of the main environmental stress factors for Pseudomonas aeruginosa. Exposure to high UVA doses produces lethal effects by the action of the reactive oxygen species (ROS) it generates. P. aeruginosa has several enzymes, including KatA and KatB catalases, which provide detoxification of ROS. We have previously demonstrated that KatA is essential in defending P. aeruginosa against high UVA doses. In order to analyse the mechanisms involved in the adaptation of this micro-organism to UVA, we investigated the effect of exposure to low UVA doses on KatA and KatB activities, and the physiological consequences. Exposure to UVA induced total catalase activity; assays with non-denaturing polyacrylamide gels showed that both KatA and KatB activities were increased by radiation. This regulation occurred at the transcriptional level and depended, at least partly, on the increase in H2O2 levels. We demonstrated that exposure to low UVA produced a protective effect against subsequent lethal doses of UVA, sodium hypochlorite and H2O2. Protection against lethal UVA depends on katA, whilst protection against sodium hypochlorite depends on katB, demonstrating that different mechanisms are involved in the defence against these oxidative agents, although both genes can be involved in the global cellular response. Conversely, protection against lethal doses of H2O2 could depend on induction of both genes and/or (an)other defensive factor(s). A better understanding of the adaptive response of P. aeruginosa to UVA is relevant from an ecological standpoint and for improving disinfection strategies that employ UVA or solar irradiation.

In Vitro Antiproliferative Effect of the Acetone Extract of Rubus fairholmianus Gard. Root on Human Colorectal Cancer Cells

PubMed Central

Plackal Adimuriyil George, Blassan; Tynga, Ivan Mfouo

2015-01-01

Plants and plant derived products exert chemopreventive effects on various cancer cell lines by the induction of cell death mechanisms. The effects of root acetone extract of Rubus fairholmianus (RFRA) on the proliferation of human colorectal cancer (Caco-2) cells have been investigated in this study. The extract led to a dose dependent decrease in both viability and proliferation and increased cytotoxicity using trypan blue exclusion, adenosine 5′-triphosphate (ATP), and lactate dehydrogenase (LDH) assay. The morphological features of the treated cells were supportive for the antiproliferative activity. The Annexin V/propidium iodide staining indicated that R. fairholmianus induced toxic effects in Caco-2 cells and the percentages of the early and late apoptotic population significantly increased when compared with control cells. Also we studied the apoptosis inducing ability of the extract by analysing caspase 3/7 activity and the induction of cell death via the effector caspases was confirmed; the activity increased in treated cells compared with control. Thus the present findings highlight that the R. fairholmianus root acetone extract exhibits antiproliferative activity on Caco-2 cells by the induction of apoptosis via caspase dependent pathway. PMID:26078938

2',4'-dihydroxychalcone, a flavonoid isolated from Herba oxytropis, suppresses PC-3 human prostate cancer cell growth by induction of apoptosis.

PubMed

Sheng, Yuqing; Zou, Mingchang; Wang, Yan; Li, Qiheng

2015-12-01

Natural products are a promising source for the development of novel cancer therapies, due to their potential effectiveness and low toxicity profiles. As a main component of Herba oxytropis , 2',4'-dihydroxychalcone (TFC) is known to demonstrate anti-tumor activity in vitro . In the present study, TFC was found to potently inhibit proliferation and induce apoptosis in PC-3 human prostate cancer cells in a dose-dependent manner. The results demonstrated that the induction of apoptosis is associated with cell cycle arrest at the G0/G1 phase and activation of caspase-3/-7. Additional mechanistic studies of two biomarkers, phosphatase and tensin homolog (PTEN) and cyclin-dependent kinase inhibitor 1B (p27 Kip1 ), in prostate cancer revealed that TFC treatment significantly upregulated the expression of PTEN and p27 Kip1 . The findings of the present study indicate that TFC-induced apoptosis in PC-3 cells via upregulation of PTEN and p27 Kip1 , which results in cell cycle arrest in G0/G1 phase, activation of caspase-3/-7 and induction of apoptosis. Therefore, TFC may be a potential compound for human prostate cancer therapy.

Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints.

PubMed

Cacao, Eliedonna; Hada, Megumi; Saganti, Premkumar B; George, Kerry A; Cucinotta, Francis A

2016-01-01

The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictions of the charge number and energy dependence of RBE's using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE's are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (<10) are found for simple exchanges using a linear dose response model, however in the non-targeted effects model for fibroblast cells large RBE values (>10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE's against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Comparisons of the resulting model parameters to those used in the NASA radiation quality factor function are discussed.

Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints

DOE PAGES

Cacao, Eliedonna; Hada, Megumi; Saganti, Premkumar B.; ...

2016-04-25

The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictionsmore » of the charge number and energy dependence of RBE’s using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE’s are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (<10) are found for simple exchanges using a linear dose response model, however in the non-targeted effects model for fibroblast cells large RBE values (>10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE’s against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Finally, we discuss comparisons of the resulting model parameters to those used in the NASA radiation quality factor function.« less

Relative Biological Effectiveness of HZE Particles for Chromosomal Exchanges and Other Surrogate Cancer Risk Endpoints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cacao, Eliedonna; Hada, Megumi; Saganti, Premkumar B.

The biological effects of high charge and energy (HZE) particle exposures are of interest in space radiation protection of astronauts and cosmonauts, and estimating secondary cancer risks for patients undergoing Hadron therapy for primary cancers. The large number of particles types and energies that makeup primary or secondary radiation in HZE particle exposures precludes tumor induction studies in animal models for all but a few particle types and energies, thus leading to the use of surrogate endpoints to investigate the details of the radiation quality dependence of relative biological effectiveness (RBE) factors. In this report we make detailed RBE predictionsmore » of the charge number and energy dependence of RBE’s using a parametric track structure model to represent experimental results for the low dose response for chromosomal exchanges in normal human lymphocyte and fibroblast cells with comparison to published data for neoplastic transformation and gene mutation. RBE’s are evaluated against acute doses of γ-rays for doses near 1 Gy. Models that assume linear or non-targeted effects at low dose are considered. Modest values of RBE (<10) are found for simple exchanges using a linear dose response model, however in the non-targeted effects model for fibroblast cells large RBE values (>10) are predicted at low doses <0.1 Gy. The radiation quality dependence of RBE’s against the effects of acute doses γ-rays found for neoplastic transformation and gene mutation studies are similar to those found for simple exchanges if a linear response is assumed at low HZE particle doses. Finally, we discuss comparisons of the resulting model parameters to those used in the NASA radiation quality factor function.« less

Analyzing the dose-dependence of the Saccharomyces cerevisiae global transcriptional response to methyl methanesulfonate and ionizing radiation.

PubMed

Benton, Michael G; Somasundaram, Swetha; Glasner, Jeremy D; Palecek, Sean P

2006-12-01

One of the most crucial tasks for a cell to ensure its long term survival is preserving the integrity of its genetic heritage via maintenance of DNA structure and sequence. While the DNA damage response in the yeast Saccharomyces cerevisiae, a model eukaryotic organism, has been extensively studied, much remains to be elucidated about how the organism senses and responds to different types and doses of DNA damage. We have measured the global transcriptional response of S. cerevisiae to multiple doses of two representative DNA damaging agents, methyl methanesulfonate (MMS) and gamma radiation. Hierarchical clustering of genes with a statistically significant change in transcription illustrated the differences in the cellular responses to MMS and gamma radiation. Overall, MMS produced a larger transcriptional response than gamma radiation, and many of the genes modulated in response to MMS are involved in protein and translational regulation. Several clusters of coregulated genes whose responses varied with DNA damaging agent dose were identified. Perhaps the most interesting cluster contained four genes exhibiting biphasic induction in response to MMS dose. All of the genes (DUN1, RNR2, RNR4, and HUG1) are involved in the Mec1p kinase pathway known to respond to MMS, presumably due to stalled DNA replication forks. The biphasic responses of these genes suggest that the pathway is induced at lower levels as MMS dose increases. The genes in this cluster with a threefold or greater transcriptional response to gamma radiation all showed an increased induction with increasing gamma radiation dosage. Analyzing genome-wide transcriptional changes to multiple doses of external stresses enabled the identification of cellular responses that are modulated by magnitude of the stress, providing insights into how a cell deals with genotoxicity.

Morphine potentiates seizures induced by GABA antagonists and attenuates seizures induced by electroshock in the rat.

PubMed

Foote, F; Gale, K

1983-11-25

In a naloxone-reversible, dose-dependent manner, morphine (10-50 mg/kg i.p.) protected against seizures induced by maximal electroshock and increased the incidence and severity of seizures induced by bicuculline, in rats. Morphine also potentiated seizures induced by isoniazid and by picrotoxin. Thus, opiate activity influences the expression of seizures in contrasting ways depending upon the mode of seizure induction. Since morphine consistently potentiated seizures induced by interference with GABA transmission, it appears that GABAergic systems may be of particular significance for the elucidation of the varied effects of morphine on seizure susceptibility.

Apigenin Attenuates Melanoma Cell Migration by Inducing Anoikis through Integrin and Focal Adhesion Kinase Inhibition.

PubMed

Hasnat, Md Abul; Pervin, Mehnaz; Lim, Ji Hong; Lim, Beong Ou

2015-11-27

Apigenin, a nonmutagenic flavonoid, has been found to have antitumor properties and is therefore particularly relevant for the development of chemotherapeutic agents for cancers. In this study, time- and dose-dependent cell viability and cytotoxicity were assessed to determine the effects of apigenin on A2058 and A375 melanoma cells. Melanoma cells were pretreated with different concentrations of apigenin and analyzed for morphological changes, anoikis induction, cell migration, and levels of proteins associated with apoptosis. Apigenin reduced integrin protein levels and inhibited the phosphorylation of focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK1/2), which induce anoikis in human cutaneous melanoma cells. Apigenin exhibited dose-dependent inhibition of melanoma cell migration, unlike untreated controls. Furthermore, apigenin treatment increased apoptotic factors such as caspase-3 and cleaved poly(ADP-ribose) polymerase in a dose-dependent manner, demonstrating the metastasis of melanoma cells. Our results provide a new insight into the mechanisms by which apigenin prevents melanoma metastasis by sensitizing anoikis induced by the loss of integrin proteins in the FAK/ERK1/2 signaling pathway. These findings elucidate the related mechanisms and suggest the potential of apigenin in developing clinical treatment strategies against malignant melanoma.

Effects of heavy ion to the primary culture of mouse brain cells

NASA Technical Reports Server (NTRS)

Nojima, Kumie; Nakadai, Taeko; Kohno, Yukio; Vazquez, Marcelo E.; Yasuda, Nakahiro; Nagaoka, Shunji

2004-01-01

To investigate effects of low dose heavy particle radiation to CNS system, we adopted mouse neonatal brain cells in culture being exposed to heavy ions by HIMAC at NIRS and NSRL at BNL. The applied dose varied from 0.05 Gy up to 2.0 Gy. The subsequent biological effects were evaluated by an induction of apoptosis and neuron survival focusing on the dependencies of the animal strains, SCID, B6, B6C3F1, C3H, used for brain cell culture, SCID was the most sensitive and C3H the least sensitive to particle radiation as evaluated by 10% apoptotic criterion. The LET dependency was compared with using SCID and B6 cells exposing to different ions (H, C, Ne, Si, Ar, and Fe). Although no detectable LET dependency was observed in the high LET (55-200 keV/micrometers) and low dose (<0.5 Gy) regions. The survivability profiles of the neurons were different in the mouse strains and ions. In this report, a result of memory and learning function to adult mice after whole-body and brain local irradiation at carbon ion and iron ion.

Zoledronic acid induces dose-dependent increase of antigen-specific CD8 T-cell responses in combination with peptide/poly-IC vaccine.

PubMed

Park, Hye-Mi; Cho, Hyun-Il; Shin, Chang-Ae; Shon, Hyun-Jung; Kim, Tai-Gyu

2016-03-04

Zoledronic acid (ZA) is used for treating osteoporosis and for preventing skeletal fractures in cancer patients suffering from myeloma and prostate cancer. It is also reported to directly induce cancer cell apoptosis and indirectly modulate T-cell immune response as an antitumor agent. In this study, the effect of ZA following peptide/polyinosinic-polycytidylic acid (poly-IC) vaccination was investigated in a murine tumor model. The combination of ZA with peptide/poly-IC vaccine showed a synergistic effect on the induction of antigen-specific CD8 T-cell response. Three consecutive intravenous administrations of ZA was defined to induce the highest CD8 T-cell response. Further, total splenocyte counts and antigen-specific CD8 T-cell response gradually increased depending on the dose of ZA. In tumor-bearing mice, ZA showed a dose-dependent decrease of growth and prolonged survival. Treatment with ZA only decreased the number of CD11b(+)Gr1(+) myeloid cells in blood. Our results demonstrate that the use of ZA could improve antitumor immune responses induced by the peptide/poly-IC vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

Non-induction of radioadaptive response in zebrafish embryos by neutrons

PubMed Central

Ng, Candy Y.P.; Kong, Eva Y.; Kobayashi, Alisa; Suya, Noriyoshi; Uchihori, Yukio; Cheng, Shuk Han; Konishi, Teruaki; Yu, Kwan Ngok

2016-01-01

In vivo neutron-induced radioadaptive response (RAR) was studied using zebrafish (Danio rerio) embryos. The Neutron exposure Accelerator System for Biological Effect Experiments (NASBEE) facility at the National Institute of Radiological Sciences (NIRS), Japan, was employed to provide 2-MeV neutrons. Neutron doses of 0.6, 1, 25, 50 and 100 mGy were chosen as priming doses. An X-ray dose of 2 Gy was chosen as the challenging dose. Zebrafish embryos were dechorionated at 4 h post fertilization (hpf), irradiated with a chosen neutron dose at 5 hpf and the X-ray dose at 10 hpf. The responses of embryos were assessed at 25 hpf through the number of apoptotic signals. None of the neutron doses studied could induce RAR. Non-induction of RAR in embryos having received 0.6- and 1-mGy neutron doses was attributed to neutron-induced hormesis, which maintained the number of damaged cells at below the threshold for RAR induction. On the other hand, non-induction of RAR in embryos having received 25-, 50- and 100-mGy neutron doses was explained by gamma-ray hormesis, which mitigated neutron-induced damages through triggering high-fidelity DNA repair and removal of aberrant cells through apoptosis. Separate experimental results were obtained to verify that high-energy photons could disable RAR. Specifically, 5- or 10-mGy X-rays disabled the RAR induced by a priming dose of 0.88 mGy of alpha particles delivered to 5-hpf zebrafish embryos against a challenging dose of 2 Gy of X-rays delivered to the embryos at 10 hpf. PMID:26850927

High dose-per-pulse electron beam dosimetry: Usability and dose-rate independence of EBT3 Gafchromic films.

PubMed

Jaccard, Maud; Petersson, Kristoffer; Buchillier, Thierry; Germond, Jean-François; Durán, Maria Teresa; Vozenin, Marie-Catherine; Bourhis, Jean; Bochud, François O; Bailat, Claude

2017-02-01

The aim of this study was to assess the suitability of Gafchromic EBT3 films for reference dose measurements in the beam of a prototype high dose-per-pulse linear accelerator (linac), capable of delivering electron beams with a mean dose-rate (Ḋ m ) ranging from 0.07 to 3000 Gy/s and a dose-rate in pulse (Ḋ p ) of up to 8 × 10 6 Gy/s. To do this, we evaluated the overall uncertainties in EBT3 film dosimetry as well as the energy and dose-rate dependence of their response. Our dosimetric system was composed of EBT3 Gafchromic films in combination with a flatbed scanner and was calibrated against an ionization chamber traceable to primary standard. All sources of uncertainties in EBT3 dosimetry were carefully analyzed using irradiations at a clinical radiotherapy linac. Energy dependence was investigated with the same machine by acquiring and comparing calibration curves for three different beam energies (4, 8 and 12 MeV), for doses between 0.25 and 30 Gy. Ḋ m dependence was studied at the clinical linac by changing the pulse repetition frequency (f) of the beam in order to vary Ḋ m between 0.55 and 4.40 Gy/min, while Ḋ p dependence was probed at the prototype machine for Ḋ p ranging from 7 × 10 3 to 8 × 10 6 Gy/s. Ḋ p dependence was first determined by studying the correlation between the dose measured by films and the charge of electrons measured at the exit of the machine by an induction torus. Furthermore, we compared doses from the films to independently calibrated thermo-luminescent dosimeters (TLD) that have been reported as being dose-rate independent up to such high dose-rates. We report that uncertainty below 4% (k = 2) can be achieved in the dose range between 3 and 17 Gy. Results also demonstrated that EBT3 films did not display any detectable energy dependence for electron beam energies between 4 and 12 MeV. No Ḋ m dependence was found either. In addition, we obtained excellent consistency between films and TLDs over the entire Ḋ p range attainable at the prototype linac confirming the absence of any dose-rate dependence within the investigated range (7 × 10 3 to 8 × 10 6 Gy/s). This aspect was further corroborated by the linear relationship between the dose-per-pulse (D p ) measured by films and the charge per pulse (C p ) measured at the prototype linac exit. Our study shows that the use of EBT3 Gafchromic films can be extended to reference dosimetry in pulsed electron beams with a very high dose rate. The measurement results are associated with an overall uncertainty below 4% (k = 2) and are dose-rate and energy independent. © 2016 American Association of Physicists in Medicine.

Effects of the UV filter benzophenone-2 on reproduction in fish

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weisbrod, Christin J.; Kunz, Petra Y.; Zenker, Armin K.

2007-12-15

The UV filter benzophenone-2 (BP-2) is largely used in personal care products such as cosmetics and in numerous other materials for UV protection. Like other UV filters, BP-2 has been found to be estrogenic in vitro and in vivo, but potential effects on reproduction of fish are unknown. In this study, we evaluate whether BP-2 affects important reproductive parameters such as fecundity, gametogenesis and secondary sex characteristics. After a pre-exposure period of 19 days, reproductively mature fathead minnows (Pimephales promelas) were exposed to 0.002, 0.1, 1.2, 5.0 and 9.7 mg/L BP-2 for 15 days. BP-2 was accumulated in fish upmore » to 3.1 {mu}g/g body weight. In males, a dose-dependent vitellogenin induction and decrease in the number of nuptial tubercles occurred. Moreover, significant dose-related effects on gonads of male and female fish were observed. At concentrations of 1.2 mg/L and higher, spermatocyte and oocyte development was significantly inhibited in male and female fish, respectively. Testes of exposed males had much fewer spermatocytes and ovaries of exposed females had much fewer mature and more atretic follicles. Reproduction was negatively affected in a dose-dependent manner with a decrease in egg production at 5.0 mg/L and a complete cessation of spawning activity at 9.7 mg/L BP-2. Our findings show significant estrogenic effects of the common UV filter BP-2 on vitellogenin induction, secondary sex characteristics, gonadal development, and reproduction in fish.« less

Antiproliferative Activity and Apoptosis Inducing Mechanism of Anthocephalus cadamba on Dalton’s Lymphoma Ascites Cells

PubMed Central

Dolai, Narayan; Islam, Aminul; Haldar, Pallab Kanti

2016-01-01

The purpose of this investigation was to evaluate the antiproliferative and apoptogenic mechanistic studies of methanol extract of Anthocephalus cadamba (MEAC) on Dalton’s lymphoma ascites (DLA) cells treated mice. Determination of antiproliferative activity was performed by using different DLA cells (2×106 cells, i.p.) inoculated mice groups (n = 12). Groups were treated for 14 consecutive days with MEAC at the doses of 200 and 400 mg/Kg b.w. respectively. The mechanism of antiproliferation activity of MEAC was investigated through morphological studies by acridine orange (AO)/ethidium bromide (EB) double staining method. Comet assay was estimated to check the DNA damage induced apoptosis property. Furthermore, flow cytometry (FACS) was used to quantitatively detect the apoptotic rate by double labeling techniques using Annexin-V FITC/propidium iodide staining analysis and apoptotic proteins expression done by western blotting assay method. MEAC exhibited significant (p<0.01) decrease the tumor volume, viable cell count, tumor weight and elevated the life span of DLA tumor bearing mice. Analysis of AO/EB staining and flow cytometry showed that MEAC possessed apoptosis induced antitumor activity on DLA cells in a dose dependant manner. Dose dependent induction of DNA damage on DLA cells were observed after MEAC treatment, which was evident from the appearance of comet tail length. Pro-apoptotic gene, Bax was up-regulated and down-regulation of the Bcl-2/Bax ratio, suggesting that Bcl-2 family involved in the control of apoptosis. Experimental results revealed that MEAC possess potent antitumor activity via induction of cancer cell apoptosis mechanism. PMID:27980586

15-Deoxy-{delta}{sup 12,14}-prostaglandin J{sub 2}-induced down-regulation of endothelial nitric oxide synthase in association with HSP70 induction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hwang, Jinah; Lee, Hyun-Il; Chang, Young-Sun

2007-05-25

A natural ligand of peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}), 15-deoxy-{delta}{sup 12,14}-prostaglandin J{sub 2} (15d-PGJ{sub 2}), decreases endothelial nitric oxide synthase (eNOS) expression by an unknown mechanism. Here we found that 15d-PGJ{sub 2}-induced eNOS reduction is inversely associated with heat shock protein 70 (HSP70) induction in endothelial cells. Treatment of cells with 15d-PGJ{sub 2} decreased eNOS protein expression in a concentration- and time-dependent manner, but independently of PPAR{gamma} with no effect on mRNA levels. Although 15d-PGJ{sub 2} elicited endothelial apoptosis, inhibition of both pan-caspases and cathepsins failed to reverse reduction of eNOS protein. Interestingly, we observed that 15d-PGJ{sub 2} induced HSP70more » in a dose-dependent manner. Immunoprecipitation and heat shock treatment demonstrated that eNOS reduction was strongly related to HSP70 induction. Cellular fractionation revealed that treatment with 15d-PGJ{sub 2} increased eNOS distribution 2.5-fold from soluble to insoluble fractions. These findings provide new insights into mechanisms whereby eNOS regulation by 15d-PGJ{sub 2} is related to HSP70 induction.« less

Comparative Effectiveness of Mesalamine, Sulfasalazine, Corticosteroids, and Budesonide for the Induction of Remission in Crohn's Disease: A Bayesian Network Meta-analysis.

PubMed

Coward, Stephanie; Kuenzig, M Ellen; Hazlewood, Glen; Clement, Fiona; McBrien, Kerry; Holmes, Rebecca; Panaccione, Remo; Ghosh, Subrata; Seow, Cynthia H; Rezaie, Ali; Kaplan, Gilaad G

2017-03-01

Induction treatment of mild-to-moderate Crohn's disease is controversial. To compare the induction of remission between different doses of mesalamine, sulfasalazine, corticosteroids, and budesonide for active Crohn's disease. We identified randomized controlled trials from existing Cochrane reviews and an updated literature search in Medline, EMBASE, and CENTRAL to November 2015. We included randomized controlled trials (n = 22) in adult patients with Crohn's disease that compared budesonide, sulfasalazine, mesalamine, or corticosteroids with placebo or each other, for the induction of remission (8-17 wks). Mesalamine (above and below 2.4 g/d) and budesonide (above and below 6 mg/d) were stratified into low and high doses. Our primary outcome was remission, defined as a Crohn's Disease Activity Index score <150. A Bayesian random-effects network meta-analysis was performed on the proportion in remission. Corticosteroids (odds ratio [OR] = 3.80; 95% credible interval [CrI]: 2.48-5.66), high-dose budesonide (OR = 2.96; 95% CrI: 2.06-4.30), and high-dose mesalamine (OR = 2.29; 95% CrI: 1.58-3.33) were superior to placebo. Corticosteroids were similar to high-dose budesonide (OR = 1.21; 95% CrI: 0.84-1.76), but more effective than high-dose mesalamine (OR = 1.83; 95% CrI: 1.16-2.88). Sulfasalazine was not significantly superior to any therapy including placebo. Randomized controlled trials that use a strict definition of induction of remission and disease severity at enrollment to assess effectiveness in treating mild-to-moderate Crohn's disease are limited. Corticosteroids and high-dose budesonide were effective treatments for inducing remission in mild-to-moderate Crohn's disease. High-dose mesalamine is an option among patients preferring to avoid steroids.

Suppression of phytohemagglutinin-induction of thymidine uptake in guinea pig lymphocytes by methylglyoxal bis(guanylhydrazone) treatment.

PubMed

Otani, S; Matsui, I; Morisawa, S

1977-10-18

Treatment with methylglyoxal bis(guanylhydrazone), a specific inhibitor of S-adenosylmethionine decarboxylase (EC 4.1.1.50), suppressed the phytohemagglutinin-induction of [3H]thymidine uptake by guinea pig lymphocytes. The kinetics of [3H]thymidine uptake revealed that the Km value for thymidine was not changed, but the V value was markedly lowered by the methylglyoxal bis(guanylhydrazone) treatment. The induction of ATP: thymidine 5'-phosphotransferase (EC 2.7.1.75) (thymidine kinase) activity by phytohemagglutinin was suppressed to about the same extent as the induction of thymidine uptake. These suppressions were dependent on the methylglyoxal bis(guanylhydrazone) doses and on duration of the methylglyoxal bis(guanylhydrazone) treatment. Analysis of [3H]thymidine labelled compounds of the acid-soluble fraction showed that conversion of thymidine to thymidine 5'-triphosphate was inhibited by the methylglyoxal bis(guanylhydrazone) treatment. DNA polymerase activity was less inhibited by the methylglyoxal bis(guanylhydrazone) treatment in comparison with the methylglyoxal bis(guanylhydrazone) inhibition of thymidine uptake by whole cells. These results strongly suggested that blocking of polyamine accumulation by the methylglyoxal bis(guanylhydrazone) treatment influenced phytohemagglutinin induction of thymidine phosphorylation, resulting in a decrease of thymidine incorporation into DNA.

Evaluation of Rifampin's Transporter Inhibitory and CYP3A Inductive Effects on the Pharmacokinetics of Venetoclax, a BCL-2 Inhibitor: Results of a Single- and Multiple-Dose Study.

PubMed

Agarwal, Suresh K; Hu, Beibei; Chien, David; Wong, Shekman L; Salem, Ahmed Hamed

2016-11-01

Venetoclax is a selective, potent, first-in-class B-cell lymphoma-2 inhibitor that has demonstrated clinical efficacy in a variety of hematological malignancies. A single-dose and multiple-dose rifampin study was conducted to evaluate the effect of CYP3A induction and transporter inhibition on the pharmacokinetics of venetoclax. Subjects received a single dose of venetoclax 200 mg on day 1 of period 1 and days 1 and 14 of period 2, a single dose of rifampin 600 mg on day 1 of period 2, and rifampin 600 mg once daily on days 5 through 17 of period 2. Blood samples were collected up to 96 hours after each venetoclax dose on day 1 of period 1 and days 1 and 14 of period 2. Compared with venetoclax alone, coadministration with a single dose of rifampin increased venetoclax C max and AUC ∞ by 106% (90%CI, 73%-145%) and 78% (90%CI, 50%-111%), respectively, whereas coadministration with multiple doses of rifampin decreased venetoclax C max and AUC ∞ by 42% (90%CI, 31%-52%) and 71% (90%CI, 66%-76%), respectively. It was possible to isolate the net effect of chronic CYP3A induction from acute P-glycoprotein (P-gp) inhibition by comparing venetoclax exposures following coadministration with multiple doses of rifampin versus a single dose of rifampin, which showed that CYP3A induction decreased venetoclax C max and AUC by 72% and 84%, respectively. These results are consistent with venetoclax being a P-gp substrate and indicate that CYP3A plays a major role in venetoclax metabolism. Prescribers should consider agents with little or no CYP3A induction during treatment with venetoclax. © 2016, The American College of Clinical Pharmacology.

Second trimester medical abortion with mifepristone followed by unlimited dosing of buccal misoprostol in Armenia.

PubMed

Louie, Karmen S; Chong, Erica; Tsereteli, Tamar; Avagyan, Gayane; Abrahamyan, Ruzanna; Winikoff, Beverly

2017-02-01

The aim of the study was to assess the efficacy and acceptability of a regimen using mifepristone and buccal misoprostol with unlimited dosing for second trimester abortion in Armenia. Women seeking to terminate 13-22 week pregnancies were enrolled in the study. Participants swallowed 200 mg mifepristone in the clinic and were instructed to return to the hospital for induction 24-48 h later. During induction, women were given 400 μg buccal misoprostol every 3 h until the fetus and placenta were expelled. The abortion was considered a success if complete uterine evacuation was achieved without oxytocin or surgery. A total of 120 women with a median gestational age of 18 weeks participated in the study. All women began misoprostol induction around 24 h after taking mifepristone. Complete uterine evacuation was achieved in 119 (99.2%) women. The median induction-to-abortion interval was 10.3 h (range 4-17.4) with a mean of 9.5 ± 2.5 h. A median of four misoprostol doses (range 2-6) with a mean of 4 ± 1 misoprostol doses were administered. The induction-to-abortion interval, number of misoprostol doses, pain score and analgesia use increased as gestational age advanced. Acceptability of the method was high among both patients and providers. The medical abortion regimen of 200 mg mifepristone followed 24 h later by induction with 400 μg buccal misoprostol administered every 3 h, with no limit on the number of doses used for the termination of pregnancies of 13-22 weeks' gestation is an effective and acceptable option for women.

Electroencephalographic response following midazolam-induced general anesthesia: relationship to plasma and effect-site midazolam concentrations.

PubMed

Miyake, Wakako; Oda, Yutaka; Ikeda, Yuko; Hagihira, Satoshi; Iwaki, Hiroyoshi; Asada, Akira

2010-06-01

To examine the relationships between effect-site concentrations and electroencephalographic parameters after the induction of general anesthesia with midazolam. Twenty-four patients with American Society of Anesthesiologists status I or II were randomly allocated to receive either an intravenous (i.v.) bolus of midazolam 0.2 mg kg(-1) (small-dose group, n = 12) or 0.3 mg kg(-1) (large-dose group, n = 12) for induction of general anesthesia in a double-blind experimental design. The bispectral index (BIS), 95% spectral edge frequency (SEF95), spectral power density, and plasma concentrations of midazolam were measured for 60 min following the induction of general anesthesia. Plasma and simulated effect-site concentrations of midazolam were significantly higher in the large-dose group than in the small-dose group (P = 0.005 and <0.001, respectively). There was a correlation between the relative beta ratio and BIS (r (2) = 0.30, P < 0.001; n = 168); however, effect-site concentrations of midazolam showed no association with BIS, relative beta ratio, or SEF95 (r (2) = 0.07, 0.11 and 0.01, respectively; n = 168). The electroencephalographic spectral power density in the beta-band (>/=13 and <30 Hz) was significantly increased after induction and was significantly larger in the large-dose group than in the small-dose group (P = 0.009). Following the induction of general anesthesia with i.v. midazolam 0.2 or 0.3 mg kg(-1), the BIS was positively correlated with the relative beta ratio. Despite a rapid decrease in the plasma and effect-site concentrations of midazolam, the average BIS remained >60 for 60 min after induction, reflecting an increased power of the electroencephalographic high-frequency band.

Characterization of an Opioid-Like Hibernation Induction Trigger

DTIC Science & Technology

1989-07-01

to HIT administration with a dose -reryonse relationship between the amount of adenosina dijphosphate (ADP) added and the extent of aggregation. However...despite the use of high doses of ADP. Our preliminary results suggest that one mechanism of prolonged organ survival following HIT administration may...HIT administration despite high dose ADP to stimulate aggregation . . . . 36 -3- INTRODUCTION A hibernation induction trigger (HIT) molecule derived

Temporal aspects of tumorigenic response to individual and mixed carcinogens. Comprehensive progress report, June 1, 1975--May 31, 1978. [Mouse skin, rats, hamsters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Albert, R.E.; Burns, F.J.; Altshuler, B.

1978-02-01

The research proposed here is designed to obtain a better understanding of the temporal kinetics of tumor induction when one or more carcinogens are present simultaneously or sequentially for prolonged periods of time. Studies done to date under this contract have shown that carcinogenesis in mouse skin by polycyclic aromatic hydrocarbon carcinogens is consistent with the induction of dependent and autonomous cell transformations by the carcinogen followed by the conversion of autonomous tumor cells into malignancies at a rate which is determined by the level of carcinogen exposure. Dependent cell transformations remain latent in the skin unless expressed by amore » promoting agent. Dependent neoplasia appears to follow one-hit kinetics while malignancy is a multihit endpoint. Dose-related and time-related aspects of tumor induction are separable in the initiation-promotion system of mouse skin which along with rat skin and hamster lung is being used as a model for testing hypotheses. Results to date provide the basis for a new interpretation of the linear non-threshold extrapolation model. The broad aim of the study is to provide a basis or rationale for estimating risks associated with prolonged exposures to carcinogens found in the environment and to predict how different tissues and species respond to the same carcinogens.« less

Dietary cadmium and benzo(a)pyrene increased intestinal metallothionein expression in the fish Fundulus heteroclitus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roesijadi, Guritno; Rezvankhah, Saeid; Perez-Matus, Alejandro

2008-10-17

To test the effect of dietary exposure to cadmium and benzo(a)pyrene on induction of metallothionein mRNA in the Fundulus heteroclitus, fish were individually fed a pelletized gel food containing cadmium, benzo(a)pyrene, or a combination of the two over a period of seven days, then analyzed for relative levels of metallothionein mRNA in the intestine, liver, and gill using real-time RT-qPCR. An initial experiment with only cadmium exposure showed an apparent 10-fold induction in the intestine, but no induction in liver or gill. Ingestion of contaminated pellets varied in individual fish, and because it was possible to monitor individual ingestion ratesmore » with our method, individual cadmium doses were estimated from the amount of ingested cadmium. When the levels of metallothionein mRNA were related to the dose to each fish, a linear dose-response relationship was observed for the intestine, but not the other organs, which showed no induction. In a second experiment, dose was controlled by placing the entire daily cadmium dose into a single contaminated pellet that was fed first (thereby, effectively controlling the effect of variable ingestion rates), and the interaction between cadmium and benzo(a)pyrene was also investigated. The intestine was again the primary organ for metallothionein induction by cadmium, with a 20-fold increase in metallothionein mRNA over control levels. When benzo(a)pyrene was administered together with cadmium, induction of metallothionein was potentiated by the presence of benzo(a)pyrene, with the main effect seen in the intestine, where already high levels of induction by cadmium alone increased by 1.74-fold when benzo(a)pyrene was present.« less

[Optimization of ventricular function during anesthesia induction by administering crystalloids and colloids to heart surgery patients].

PubMed

Ballesteros, M; Boldt, J; Zickmann, B; Knothe, C; Hempelmann, G

1995-01-01

To describe the changes in cardiac function after administration of three different solutions infused after anesthetic induction. Thirty-six patients scheduled for elective aortocoronary bypass surgery were randomly distributed into three groups. Over a period of 25 min after anesthetic induction, 12 received 10 ml/kg of Ringer solution (low dose crystalloid group), 12 received 20 ml/kg of Ringer solution (high dose crystalloid group), and 12 received 10 ml/kg of Ringer solution with 10 ml/kg of hydroxi-ethyl-almidon solution 450,000 D, 0.7 substitution grade (group C-HEA). Minute volume, systemic and pulmonary pressures, osmolality of blood and urine, and plasma and urine sodium concentrations were measured before and after infusion of the assigned liquid. In spite of the volume infused, low dose crystalloid group showed a high incidence of oliguria, increased urinary osmolality and decreased sodium in urine. Cardiac and systolic indices and left ventricular work load remained stable after infusion of the assigned liquid in low and high dose crystalloid groups, whereas they increased significantly ion group C-HEA (+23%, +16% and +20%). Administration of restricted doses of crystalloids after anesthetic induction favors the retention of water and sodium. Higher doses of crystalloids weaken this effect. However, neither of these two regimens leads to a more effective cardiac work load. A combination of crystalloids and colloids administered immediately after anesthetic induction temporarily improves cardiac performance during surgery.

Evaluation of the Anxiolytic Activity of NR-ANX-C (a Polyherbal Formulation) in Ethanol Withdrawal-Induced Anxiety Behavior in Rats.

PubMed

Mohan, L; Rao, U S C; Gopalakrishna, H N; Nair, V

2011-01-01

The present study investigates the anxiolytic activity of NR-ANX-C, a standardized polyherbal formulation containing the extracts of Withania somnifera, Ocimum sanctum, Camellia sinensis, Triphala, and Shilajit in ethanol withdrawal- (EW-) induced anxiety behavior in rats. Ethanol dependence in rats was produced by substitution of drinking water with 7.5% v/v alcohol for 10 days. Then, ethanol withdrawal was induced by replacing alcohol with drinking water, 12 hours prior to experimentation. After confirming induction of withdrawal symptoms in the alcohol deprived animals, the anxiolytic activity of the test compound in graded doses (10, 20, and 40 mg/kg) was compared to the standard drug alprazolam (0.08 mg/kg) in the elevated plus maze and bright and dark arena paradigms. In our study, single and repeated dose administration of NR-ANX-C reduced EW-induced anxiety in a dose-dependent manner. Even though the anxiolytic activity was not significant at lower doses, NR-ANX-C at the highest dose tested (40 mg/kg) produced significant anxiolytic activity that was comparable to the standard drug alprazolam. Based on our findings we believe that NR-ANX-C has the potential to be used as an alternative to benzodiazepines in the treatment of EW-induced anxiety.

Evaluation of the Anxiolytic Activity of NR-ANX-C (a Polyherbal Formulation) in Ethanol Withdrawal-Induced Anxiety Behavior in Rats

PubMed Central

Mohan, L.; Rao, U. S. C.; Gopalakrishna, H. N.; Nair, V.

2011-01-01

The present study investigates the anxiolytic activity of NR-ANX-C, a standardized polyherbal formulation containing the extracts of Withania somnifera, Ocimum sanctum, Camellia sinensis, Triphala, and Shilajit in ethanol withdrawal- (EW-) induced anxiety behavior in rats. Ethanol dependence in rats was produced by substitution of drinking water with 7.5% v/v alcohol for 10 days. Then, ethanol withdrawal was induced by replacing alcohol with drinking water, 12 hours prior to experimentation. After confirming induction of withdrawal symptoms in the alcohol deprived animals, the anxiolytic activity of the test compound in graded doses (10, 20, and 40 mg/kg) was compared to the standard drug alprazolam (0.08 mg/kg) in the elevated plus maze and bright and dark arena paradigms. In our study, single and repeated dose administration of NR-ANX-C reduced EW-induced anxiety in a dose-dependent manner. Even though the anxiolytic activity was not significant at lower doses, NR-ANX-C at the highest dose tested (40 mg/kg) produced significant anxiolytic activity that was comparable to the standard drug alprazolam. Based on our findings we believe that NR-ANX-C has the potential to be used as an alternative to benzodiazepines in the treatment of EW-induced anxiety. PMID:20953426

Non-Targeted Effects and the Dose Response for Heavy Ion Tumorigenesis

NASA Technical Reports Server (NTRS)

Chappelli, Lori J.; Cucinotta, Francis A.

2010-01-01

BACKGROUND: There is no human epidemiology data available to estimate the heavy ion cancer risks experienced by astronauts in space. Studies of tumor induction in mice are a necessary step to estimate risks to astronauts. Previous experimental data can be better utilized to model dose response for heavy ion tumorigenesis and plan future low dose studies. DOSE RESPONSE MODELS: The Harderian Gland data of Alpen et al.[1-3] was re-analyzed [4] using non-linear least square regression. The data set measured the induction of Harderian gland tumors in mice by high-energy protons, helium, neon, iron, niobium and lanthanum with LET s ranging from 0.4 to 950 keV/micron. We were able to strengthen the individual ion models by combining data for all ions into a model that relates both radiation dose and LET for the ion to tumor prevalence. We compared models based on Targeted Effects (TE) to one motivated by Non-targeted Effects (NTE) that included a bystander term that increased tumor induction at low doses non-linearly. When comparing fitted models to the experimental data, we considered the adjusted R2, the Akaike Information Criteria (AIC), and the Bayesian Information Criteria (BIC) to test for Goodness of fit.In the adjusted R2test, the model with the highest R2values provides a better fit to the available data. In the AIC and BIC tests, the model with the smaller values of the summary value provides the better fit. The non-linear NTE models fit the combined data better than the TE models that are linear at low doses. We evaluated the differences in the relative biological effectiveness (RBE) and found the NTE model provides a higher RBE at low dose compared to the TE model. POWER ANALYSIS: The final NTE model estimates were used to simulate example data to consider the design of new experiments to detect NTE at low dose for validation. Power and sample sizes were calculated for a variety of radiation qualities including some not considered in the Harderian Gland data set and with different background tumor incidences. We considered different experimental designs with varying number of doses and varying low doses dependant on the LET of the radiation. The optimal design to detect a NTE for an individual ion had 4 doses equally spaced below a maximal dose where bending due to cell sterilization was < 2%. For example at 100 keV/micron we would irradiate at 0.03 Gy, 0.065 Gy, 0.13 Gy, and 0.26 Gy and require 850 mice including a control dose for a sensitivity to detect NTE with 80% power. Sample sizes could be improved by combining ions similar to the methods used with the Harderian Gland data.

Repeated administration of the monoamine reuptake inhibitor BTS 74 398 induces ipsilateral circling in the 6-hydroxydopamine lesioned rat without sensitizing motor behaviours.

PubMed

Lane, E L; Cheetham, S C; Jenner, P

2005-01-01

BTS 74 398 (1-[1-(3,4-dichlorophenyl)cyclobutyl]-2-(3-diaminethylaminopropylthio)ethanone monocitrate) is a monoamine reuptake inhibitor that reverses motor deficits in MPTP-treated (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) common marmosets without provoking established dyskinesia. However, it is not known whether BTS 74 398 primes the basal ganglia for dyskinesia induction. In this study, the ability of BTS 74 398 to sensitize 6-hydroxydopamine (6-OHDA)-lesioned rats for the production of abnormal motor behaviours and the induction of striatal DeltaFosB were determined in comparison with l-3,4-dihydroxyphenylalanine methyl ester (L-dopa). Acute administration of BTS 74 398 induced a dose-dependent ipsilateral circling response in unilaterally 6-OHDA-lesioned rats whereas L-dopa produced dose-dependent contraversive rotation. The ipsilateral circling response to BTS 74 398 did not alter during 21 days of administration. In contrast, L-dopa treatment for 21 days caused a marked increase in rotational response. Repeated administration of both L-dopa and BTS 74 398 increased general motor activity and stereotypic behaviour. In L-dopa-treated rats, orolingual, locomotive, forelimb and axial abnormal movements developed whereas BTS 74 398 produced only locomotion with a side bias but no other abnormal movements. Sensitization of circling responses and the development of abnormal movements in 6-OHDA-lesioned rats have been associated with the potential of dopaminergic drugs to induce dyskinesia. Furthermore, striatal DeltaFosB immunoreactivity, shown to correlate with dyskinesia induction, was increased by L-dopa but was unaffected by repeated BTS 74 398 administration. The lack of such changes following repeated BTS 74 398 treatment suggests that it may be an effective antiparkinsonian therapy that is unlikely to produce involuntary movements.

The pharmacological effects of the anesthetic alfaxalone after intramuscular administration to dogs.

PubMed

Tamura, Jun; Ishizuka, Tomohito; Fukui, Sho; Oyama, Norihiko; Kawase, Kodai; Miyoshi, Kenjiro; Sano, Tadashi; Pasloske, Kirby; Yamashita, Kazuto

2015-03-01

The pharmacological effects of the anesthetic alfaxalone were evaluated after intramuscular (IM) administration to 6 healthy beagle dogs. The dogs received three IM doses each of alfaxalone at increasing dose rates of 5 mg/kg (IM5), 7.5 mg/kg (IM7.5) and 10 mg/kg (IM10) every other day. Anesthetic effect was subjectively evaluated by using an ordinal scoring system to determine the degree of neuro-depression and the quality of anesthetic induction and recovery from anesthesia. Cardiorespiratory variables were measured using noninvasive methods. Alfaxalone administered IM produced dose-dependent neuro-depression and lateral recumbency (i.e., 36 ± 28 min, 87 ± 26 min and 115 ± 29 min after the IM5, IM7.5 and IM10 treatments, respectively). The endotracheal tube was tolerated in all dogs for 46 ± 20 and 58 ± 21 min after the IM7.5 and IM10 treatments, respectively. It was not possible to place endotracheal tubes in 5 of the 6 dogs after the IM5 treatment. Most cardiorespiratory variables remained within clinically acceptable ranges, but hypoxemia was observed by pulse oximetry for 5 to 10 min in 2 dogs receiving the IM10 treatment. Dose-dependent decreases in rectal temperature, respiratory rate and arterial blood pressure also occurred. The quality of recovery was considered satisfactory in all dogs receiving each treatment; all the dog exhibited transient muscular tremors and staggering gait. In conclusion, IM alfaxalone produced a dose-dependent anesthetic effect with relatively mild cardiorespiratory depression in dogs. However, hypoxemia may occur at higher IM doses of alfaxalone.

The pharmacological effects of the anesthetic alfaxalone after intramuscular administration to dogs

PubMed Central

TAMURA, Jun; ISHIZUKA, Tomohito; FUKUI, Sho; OYAMA, Norihiko; KAWASE, Kodai; MIYOSHI, Kenjiro; SANO, Tadashi; PASLOSKE, Kirby; YAMASHITA, Kazuto

2014-01-01

The pharmacological effects of the anesthetic alfaxalone were evaluated after intramuscular (IM) administration to 6 healthy beagle dogs. The dogs received three IM doses each of alfaxalone at increasing dose rates of 5 mg/kg (IM5), 7.5 mg/kg (IM7.5) and 10 mg/kg (IM10) every other day. Anesthetic effect was subjectively evaluated by using an ordinal scoring system to determine the degree of neuro-depression and the quality of anesthetic induction and recovery from anesthesia. Cardiorespiratory variables were measured using noninvasive methods. Alfaxalone administered IM produced dose-dependent neuro-depression and lateral recumbency (i.e., 36 ± 28 min, 87 ± 26 min and 115 ± 29 min after the IM5, IM7.5 and IM10 treatments, respectively). The endotracheal tube was tolerated in all dogs for 46 ± 20 and 58 ± 21 min after the IM7.5 and IM10 treatments, respectively. It was not possible to place endotracheal tubes in 5 of the 6 dogs after the IM5 treatment. Most cardiorespiratory variables remained within clinically acceptable ranges, but hypoxemia was observed by pulse oximetry for 5 to 10 min in 2 dogs receiving the IM10 treatment. Dose-dependent decreases in rectal temperature, respiratory rate and arterial blood pressure also occurred. The quality of recovery was considered satisfactory in all dogs receiving each treatment; all the dog exhibited transient muscular tremors and staggering gait. In conclusion, IM alfaxalone produced a dose-dependent anesthetic effect with relatively mild cardiorespiratory depression in dogs. However, hypoxemia may occur at higher IM doses of alfaxalone. PMID:25428797

The effects of oxytocin and atosiban on the modulation of heart rate in pregnant women.

PubMed

Weissman, Amir; Tobia, Rana Swed; Burke, Yechiel Z; Maxymovski, Olga; Drugan, Arie

2017-02-01

To evaluate autonomic modulation of heart rate in pregnant women treated with oxytocin to induce labor and with atosiban (an oxytocin antagonist) to arrest preterm labor. A prospective study with two cohorts: 14 pregnant women treated with atosiban for premature uterine contractions, and 28 women undergoing induction of labor with oxytocin. Computerized analyses of the electrocardiogram were performed with spectral and nonlinear dynamic analyses. Atosiban did not alter any of the variables associated with heart rate variability, whereas oxytocin showed a dose-dependent decrease in heart rate (p < 0.05) and a significant increase in all spectral variables studied (p < 0.01). Atosiban has no adverse effects on the cardiovascular system or the modulation of heart rate. Oxytocin, on the other hand, can cause a dose-dependent bradycardic effect and an increase in the spectral power, thus should be used with caution in certain pregnant women.

Erufosine simultaneously induces apoptosis and autophagy by modulating the Akt-mTOR signaling pathway in oral squamous cell carcinoma.

PubMed

Kapoor, Vaishali; Zaharieva, Maya M; Das, Satya N; Berger, Martin R

2012-06-01

We investigated the anticancer activity of erufosine in oral squamous carcinoma cell lines in terms of cell proliferation, colony formation, induction of autophagy/apoptosis, cell cycle and mTOR signaling pathway. Erufosine showed dose-dependent cytotoxicity in all cell lines, it induced autophagy as well as apoptosis, G2 cell cycle arrest and modulation of cyclin D1 expression. Further erufosine downregulated the phosphorylation of major components of mTOR pathway, like p-Akt at Ser473 and Thr308 residues, p-Raptor, p-mTOR, p-PRAS40 and its downstream substrates p-p70S6K and p-4EBP1 in a dose-dependent manner. The pre-treatment of tumor cells with p-mTOR siRNA increased cytotoxic effects of erufosine comparable to cisplatin but higher than rapamycin. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Dose rate effect of pulsed electron beam on micronucleus frequency in human peripheral blood lymphocytes.

PubMed

Acharya, Santhosh; Sanjeev, Ganesh; Bhat, Nagesh N; Narayana, Yerol

2010-03-01

The micronucleus assay in human peripheral blood lymphocytes is a sensitive indicator of radiation damage and could serve as a biological dosimeter in evaluating suspected overexposure to ionising radiation. Micronucleus (MN) frequency as a measure of chromosomal damage has also extensively been employed to quantify the effects of radiation dose rate on biological systems. Here we studied the effects of 8 MeV pulsed electron beam emitted by Microtron electron accelerator on MN induction at dose rates between 35 Gy min-1 and 352.5 Gy min-1. These dose rates were achieved by varying the pulse repetition rate (PRR). Fricke dosimeter was employed to measure the absorbed dose at different PRR and to ensure uniform dose distribution of the electron beam. To study the dose rate effect, blood samples were irradiated to an absorbed dose of (4.7+/-0.2) Gy at different rates and cytogenetic damage was quantified using the micronucleus assay. The obtained MN frequency showed no dose rate dependence within the studied dose rate range. Our earlier dose effect study using 8 MeV electrons revealed that the response of MN was linear-quadratic. Therefore, in the event of an accident, dose estimation can be made using linear-quadratic dose response parameters, without adding dose rate as a correction factor.

STING-Dependent Interferon-λ1 Induction in HT29 Cells, a Human Colorectal Cancer Cell Line, After Gamma-Radiation.

PubMed

Chen, Jianzhou; Markelc, Bostjan; Kaeppler, Jakob; Ogundipe, Vivian M L; Cao, Yunhong; McKenna, W Gillies; Muschel, Ruth J

2018-05-01

To investigate the induction of type III interferons (IFNs) in human cancer cells by gamma-rays. Type III IFN expression in human cancer cell lines after gamma-ray irradiation in vitro was assessed by reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Signaling pathways mediating type III IFN induction were examined by a variety of means, including immunoblotting, flow cytometry, confocal imaging, and reverse transcription-quantitative polymerase chain reaction. Key mediators in these pathways were further explored and validated using gene CRISPR knockout or short hairpin RNA knockdown. Exposure to gamma-rays directly induced type III IFNs (mainly IFNL1) in human cancer cell lines in dose- and time-dependent fashions. The induction of IFNL1 was primarily mediated by the cytosolic DNA sensors-STING-TBK1-IRF1 signaling axis, with a lesser contribution from the nuclear factor kappa b signaling in HT29 cells. In addition, type III IFN signaling through its receptors serves as a positive feedback loop, further enhancing IFN expression via up-regulation of the kinases in the STING-TBK1 signaling axis. Our results suggest that IFNL1 can be up-regulated in human cancer cell lines after gamma-ray treatment. In HT29 cells this induction occurs via the STING pathway, adding another layer of complexity to the understanding of radiation-induced antitumor immunity, and may provide novel insights into IFN-based cancer treatment. Copyright © 2018 Elsevier Inc. All rights reserved.

Non-induction of radioadaptive response in zebrafish embryos by neutrons.

PubMed

Ng, Candy Y P; Kong, Eva Y; Kobayashi, Alisa; Suya, Noriyoshi; Uchihori, Yukio; Cheng, Shuk Han; Konishi, Teruaki; Yu, Kwan Ngok

2016-06-01

In vivo neutron-induced radioadaptive response (RAR) was studied using zebrafish (Danio rerio) embryos. The Neutron exposure Accelerator System for Biological Effect Experiments (NASBEE) facility at the National Institute of Radiological Sciences (NIRS), Japan, was employed to provide 2-MeV neutrons. Neutron doses of 0.6, 1, 25, 50 and 100 mGy were chosen as priming doses. An X-ray dose of 2 Gy was chosen as the challenging dose. Zebrafish embryos were dechorionated at 4 h post fertilization (hpf), irradiated with a chosen neutron dose at 5 hpf and the X-ray dose at 10 hpf. The responses of embryos were assessed at 25 hpf through the number of apoptotic signals. None of the neutron doses studied could induce RAR. Non-induction of RAR in embryos having received 0.6- and 1-mGy neutron doses was attributed to neutron-induced hormesis, which maintained the number of damaged cells at below the threshold for RAR induction. On the other hand, non-induction of RAR in embryos having received 25-, 50- and 100-mGy neutron doses was explained by gamma-ray hormesis, which mitigated neutron-induced damages through triggering high-fidelity DNA repair and removal of aberrant cells through apoptosis. Separate experimental results were obtained to verify that high-energy photons could disable RAR. Specifically, 5- or 10-mGy X-rays disabled the RAR induced by a priming dose of 0.88 mGy of alpha particles delivered to 5-hpf zebrafish embryos against a challenging dose of 2 Gy of X-rays delivered to the embryos at 10 hpf. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Evodiamine Induces Cell Growth Arrest, Apoptosis and Suppresses Tumorigenesis in Human Urothelial Cell Carcinoma Cells.

PubMed

Shi, Chung-Sheng; Li, Jhy-Ming; Chin, Chih-Chien; Kuo, Yi-Hung; Lee, Ying-Ray; Huang, Yun-Ching

2017-03-01

Evodiamine, an indole alkaloid derived from Evodia rutaecarpa, exhibits pharmacological activities including vasodilatation, analgesia, anti-cardiovascular disease, anti-Alzheimer's disease, anti-inflammation, and anti-tumor activity. This study analyzes the anti-tumor effects of evodiamine on cellular growth, tumorigenesis, cell cycle and apoptosis induction of human urothelial cell carcinoma (UCC) cells. The present study showed that evodiamine significantly inhibited the proliferation of UCC cells in a dose- and time-dependent manner. Also, evodiamine suppressed the tumorigenesis of UCC cells in vitro. Moreover, evodiamine caused G 2 /M cell-cycle arrest and induced caspase-dependent apoptosis in UCC cells. Finally, we demonstrated that evodiamine exhibits better cytotoxic than 5-fluorouracil, a clinical chemotherapeutic drug, for UCC cells. Evodiamine induces growth inhibition, tumorigenesis suppression, cell-cycle arrest, and apoptosis induction in human UCC cells. Therefore, this agent displays a therapeutic potential for treating human UCC cells and is worthy for further investigation. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

PXR-dependent induction of human CYP3A4 gene expression by organochlorine pesticides.

PubMed

Coumoul, Xavier; Diry, Monique; Barouki, Robert

2002-11-15

OCP are xenobiotics which display various toxic effects on animal and human health. One of their effects is to bind and activate estrogen receptor alpha (ERalpha). We have previously studied the down-regulation of induced CYP1A1 (cytochrome P450) expression by this class of molecules in mammary carcinoma cells and shown the importance of ERalpha in this process. However, an alternative mechanism was suggested by those experiments in hepatoma cells. In this study, we have performed Northern blot and transient transfection assays in various cell lines and shown that OCP activate human pregnane X receptor (PXR) and subsequent CYP3A4 mRNA expression. This effect is mediated by the distal xenobiotic responsive element modulator of the promoter. The induction of CYP3A4 by OCP was dose-dependent within the 1-10 microM range. The data suggest that chronic exposure to OCP could alter a major metabolite pathway in human liver and putatively modify the pharmacokinetics of drugs and pollutants.

Protective effect of Tribulus terrestris fruit extract on cerulein-induced acute pancreatitis in mice.

PubMed

Borran, Mina; Minaiyan, Mohsen; Zolfaghari, Behzad; Mahzouni, Parvin

2017-01-01

Antioxidant, anti-inflammatory, analgesic and antimicrobial activities of Tribulus terrestris ( T. terrestris ) could be helpful in the treatment of acute pancreatitis; thus, this study was designed to investigate the effects of T. terrestris on cerulein-induced acute pancreatitis in mice. Three doses (100, 200 and 400 mg/kg) of T. terrestris hydro-alcoholic extract were administered both orally (60 minutes before pancreatitis induction, p.o.) and intra-peritoneally (30 minutes before pancreatitis induction, i.p.) to different groups of mice (n=6). Pancreatitis was induced by five injections (i.p.) of cerulein 50μg/kg body weight with 1 hr intervals. Animals were euthanized 5 hr after the last injection of cerulein and tissue injures were assessed biochemically and pathologically. T. terrestris extract 200 and 400mg/kg (p.o.) and T. terrestris extract 400 mg/kg (i.p.) reduced pancreatic tissue myeloperoxidase (MPO) activity and serum amylase and lipase levels and alleviated histological parameters. These data suggest that T. terrestris hydro-alcoholic extract was effective in protecting against experimental acute pancreatitis and possibly the efficacy depends on dose and route of administration.

Inhibition by sodium nitroprusside of the expression of inducible nitric oxide synthase in rat neutrophils.

PubMed Central

Mariotto, S; Cuzzolin, L; Adami, A; Del Soldato, P; Suzuki, H; Benoni, G

1995-01-01

A well-known nitric oxide (NO)-releasing compound, sodium nitroprusside (SNP), decreases in a dose-dependent manner NO synthase (NOS) activity induced in rat neutrophils by treatment with lipopolysaccharide (LPS). This inhibitory action of SNP seems not to be due to its direct effect on the enzyme activity. The strong nitrosonium ion (NO+) character of SNP could be responsible for its inhibition of NOS induction in neutrophils. PMID:7542530

Psilocybin dose-dependently causes delayed, transient headaches in healthy volunteers

PubMed Central

Johnson, Matthew W.; Sewell, R. Andrew; Griffiths, Roland R.

2011-01-01

Background Psilocybin is a well-characterized classic hallucinogen (psychedelic) with a long history of religious use by indigenous cultures, and nonmedical use in modern societies. Although psilocybin is structurally related to migraine medications, and case studies suggest that psilocybin may be efficacious in treatment of cluster headache, little is known about the relationship between psilocybin and headache. Methods This double-blind study examined a broad range of psilocybin doses (0, 5, 10, 20, and 30 mg/70 kg) on headache in 18 healthy participants. Results Psilocybin frequently caused headache, the incidence, duration, and severity of which increased in a dose-dependent manner. All headaches had delayed onset, were transient, and lasted no more than a day after psilocybin administration. Conclusions Possible mechanisms for these observations are discussed, and include induction of delayed headache through nitric oxide release. These data suggest that headache is an adverse event to be expected with the nonmedical use of psilocybin-containing mushrooms as well as the administration of psilocybin in human research. Headaches were neither severe nor disabling, and should not present a barrier to future psilocybin research. PMID:22129843

Psilocybin dose-dependently causes delayed, transient headaches in healthy volunteers.

PubMed

Johnson, Matthew W; Sewell, R Andrew; Griffiths, Roland R

2012-06-01

Psilocybin is a well-characterized classic hallucinogen (psychedelic) with a long history of religious use by indigenous cultures, and nonmedical use in modern societies. Although psilocybin is structurally related to migraine medications, and case studies suggest that psilocybin may be efficacious in treatment of cluster headache, little is known about the relationship between psilocybin and headache. This double-blind study examined a broad range of psilocybin doses (0, 5, 10, 20, and 30 mg/70 kg) on headache in 18 healthy participants. Psilocybin frequently caused headache, the incidence, duration, and severity of which increased in a dose-dependent manner. All headaches had delayed onset, were transient, and lasted no more than a day after psilocybin administration. Possible mechanisms for these observations are discussed, and include induction of delayed headache through nitric oxide release. These data suggest that headache is an adverse event to be expected with the nonmedical use of psilocybin-containing mushrooms as well as the administration of psilocybin in human research. Headaches were neither severe nor disabling, and should not present a barrier to future psilocybin research. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The anti-canine distemper virus activities of ex vivo-expanded canine natural killer cells.

PubMed

Park, Ji-Yun; Shin, Dong-Jun; Lee, Soo-Hyeon; Lee, Je-Jung; Suh, Guk-Hyun; Cho, Duck; Kim, Sang-Ki

2015-04-17

Natural killer (NK) cells play critical roles in induction of antiviral effects against various viruses of humans and animals. However, few data on NK cell activities during canine distemper virus (CDV) infections are available. Recently, we established a culture system allowing activation and expansion of canine non-B, non-T, large granular NK lymphocytes from PBMCs of normal dogs. In the present study, we explored the ability of such expanded NK cells to inhibit CDV infection in vitro. Cultured CD3-CD5-CD21- NK cells produced large amounts of IFN-γ, exhibited highly upregulated expression of mRNAs encoding NK-cell-associated receptors, and demonstrated strong natural killing activity against canine tumor cells. Although the expanded NK cells were dose-dependently cytotoxic to both normal and CDV-infected Vero cells, CDV infection rendered Vero cells more susceptible to NK cells. Pretreatment with anti-CDV serum from hyperimmunized dogs enhanced the antibody-dependent cellular cytotoxicity (ADCC) of NK cells against CDV-infected Vero cells. The culture supernatants of NK cells, added before or after infection, dose-dependently inhibited both CDV replication and development of CDV-induced cytopathic effects (CPEs) in Vero cells. Anti-IFN-γ antibody neutralized the inhibitory effects of NK cell culture supernatants on CDV replication and CPE induction in Vero cells. Such results emphasize the potential significance of NK cells in controlling CDV infection, and indicate that NK cells may play roles both during CDV infection and in combating such infections, under certain conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

Convergence of hepcidin deficiency, systemic iron overloading, heme accumulation, and REV-ERBα/β activation in aryl hydrocarbon receptor-elicited hepatotoxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fader, Kelly A.; Nault, Rance

Persistent aryl hydrocarbon receptor (AhR) agonists elicit dose-dependent hepatic lipid accumulation, oxidative stress, inflammation, and fibrosis in mice. Iron (Fe) promotes AhR-mediated oxidative stress by catalyzing reactive oxygen species (ROS) production. To further characterize the role of Fe in AhR-mediated hepatotoxicity, male C57BL/6 mice were orally gavaged with sesame oil vehicle or 0.01–30 μg/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) every 4 days for 28 days. Duodenal epithelial and hepatic RNA-Seq data were integrated with hepatic AhR ChIP-Seq, capillary electrophoresis protein measurements, and clinical chemistry analyses. TCDD dose-dependently repressed hepatic expression of hepcidin (Hamp and Hamp2), the master regulator of systemic Fe homeostasis, resultingmore » in a 2.6-fold increase in serum Fe with accumulating Fe spilling into urine. Total hepatic Fe levels were negligibly increased while transferrin saturation remained unchanged. Furthermore, TCDD elicited dose-dependent gene expression changes in heme biosynthesis including the induction of aminolevulinic acid synthase 1 (Alas1) and repression of uroporphyrinogen decarboxylase (Urod), leading to a 50% increase in hepatic hemin and a 13.2-fold increase in total urinary porphyrins. Consistent with this heme accumulation, differential gene expression suggests that heme activated BACH1 and REV-ERBα/β, causing induction of heme oxygenase 1 (Hmox1) and repression of fatty acid biosynthesis, respectively. Collectively, these results suggest that Hamp repression, Fe accumulation, and increased heme levels converge to promote oxidative stress and the progression of TCDD-elicited hepatotoxicity. - Highlights: • TCDD represses hepatic hepcidin expression, leading to systemic iron overloading. • Dysregulation of heme biosynthesis is consistent with heme and porphyrin accumulation. • Heme-activated REV-ERBα/β repress circadian-regulated hepatic lipid metabolism. • Disruption of iron homeostasis promotes TCDD-elicited steatohepatitis with fibrosis.« less

Mutation induction in haploid yeast after split-dose radiation-exposure. I. Fractionated UV-irradiation.

PubMed

Schenk, K; Zölzer, F; Kiefer, J

1989-01-01

Mutation induction was investigated in wild-type haploid yeast Saccharomyces cerevisiae after split-dose UV-irradiation. Cells were exposed to fractionated 254 nm-UV-doses separated by intervals from 0 to 6 h with incubation either on non-nutrient or nutrient agar between. The test parameter was resistance to canavanine. If modifications of sensitivity due to incubation are appropriately taken into account there is no change of mutation frequency.

Immunohistochemical analysis of cytochrome P4501A induction in organs and cell types of Rivulus marmoratus exposed to waterborne 2,3,7,8-tetrachlorodibenzo-p-dioxin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stegeman, J.; Smolowitz, R.; Burnett, K.

1994-12-31

Identifying target cells and organs is critical to establishing the sites and mechanisms of toxicity of Ah-receptor agonists. Previous studies have described the localization of CYPLA induced in multiple organs of fish exposed to Ah-receptor agonists. Here the authors compare the responses in multiple cell types and organs of small fish (Rivulus) exposed to waterborne TCDD. Adult fish were exposed to TCDD at concentrations from 0.01 to 10 ng/liter for 48 hours, then prepared and analyzed by immunohistochemistry with monoclonal antibody to teleost CYPIAI. At the highest dose profound induction was detected in virtually every organ. Structures staining intensely were:more » nasal and cephalic chemoreceptors, including sensory and basal cells; superficial cells in skin and pharynx; cartilage cells (chondrocytes) in the head, gills, growth plates and fins; epithelial and endothelial cells of liver, gut, kidney, and gill; pseudobranch vessels and glandular cells; eye lens epithelium; endothelium in vessels of eye, brain, skin, muscle, thymus and gonad. Lesser concentrations of TCDD elicited less strong responses, and control fish showed mild staining only in cartilage structures. The dose-dependent patterns of induction differed between different cell types. Responsive cells identified is these fish indicate sites where toxicity associated with Ah-receptor agonists or with CYPLA function may be expressed.« less

A prospective randomized trial comparing Foley catheter, oxytocin, and combination Foley catheter-oxytocin for labour induction with unfavourable cervix.

PubMed

El Khouly, Nabih I

2017-04-01

The purpose of this study was to evaluate the effectiveness and safety of transcervical Foley catheter with and without oxytocin versus oxytocin alone for labour induction with unfavourable cervix. This trial enrolled 108 women with singleton pregnancies presented for labour induction with unfavourable cervix. Patients were randomly assigned to receive Foley catheter alone (I), Foley catheter plus oxytocin (II) or oxytocin alone (III). Outcomes were analysed in terms of success of induction, induction delivery interval, route of delivery, dose and duration of oxytocin, and complications. Successful normal vaginal delivery was more common in group I (p = .02) compared to group III. Induction delivery time was statistically shorter in group II and group III (p < .001). Patients in group I required significantly less oxytocin dose and duration (p < .001). This led to our conclusion that induction of labour with Foley catheter without oxytocin increases success rate of normal vaginal delivery; however, it has a longer induction delivery interval with similar complications.

Successful pregnancy following low-dose hCG administration in addition to hMG in a patient with hypothalamic amenorrhea due to weight loss.

PubMed

Tsutsumi, Ryo; Fujimoto, Akihisa; Osuga, Yutaka; Harada, Miyuki; Takemura, Yuri; Koizumi, Minako; Yano, Tetsu; Taketani, Yuji

2012-06-01

We describe successful ovulation induction with low-dose hCG administration in addition to hMG in a patient with refractory hypothalamic amenorrhea. A 24-year-old woman with weight loss-related amenorrhea underwent ovulation induction and intracytoplasmic sperm injection (ICSI). Administration of exogenous gonadotropins was ineffective in ovulation induction. Supplementation with low-dose hCG in order to increase luteinizing hormone (LH) activity in the late follicular phase produced late folliculogenesis and steroidogenesis, and ovulation was then successfully induced. This report reacknowledges the critical role that LH plays cooperatively with follicle-stimulating hormone in both folliculogenesis and steroidogenesis.

Comparison of Adrenal Suppression between Etomidate and Dexmedetomidine in Children with Congenital Heart Disease.

PubMed

Gu, Hongbin; Zhang, Mazhong; Cai, Meihua; Liu, Jinfen

2015-05-29

The aim of this study was to compare plasma cortisol concentration during anesthesia of children with congenital heart disease who received dexmedetomidine (DEX) with those who received etomidate (ETO). We recruited 99 ASA physical status II-III pediatric patients scheduled for congenital heart disease (CHD) corrective surgery and divided into them into 3 groups. Group DEX received an infusion of DEX intravenously with a bolus dose of 0.5 µg·kg-1 within 10 min during anesthesia induction, followed by a maintenance dose of DEX 0.5 µg·kg-1·h-1. Group ETO received ETO intravenously with a bolus dose of 0.3 mg·kg-1 without a maintenance dose. Group CON received routine anesthetics as controls. The preset timepoints were: before anesthesia induction (T0), at the end of induction (T1), 30 min after anesthesia induction (T2), at the time of aortic and inferior vena catheterization (T3), and at 180 min (T4) and 24 h (T5) after anesthesia induction. The cortisol concentration decreased gradually after anesthesia induction in all groups, and returned to baseline values after 24 h. The cortisol concentration was significantly lower in Group ETO children than in Group DEX or group CON at T4. The plasma concentrations of cortisol decreased in CHD children after the operation, but returned to baseline after 24 h of anesthesia induction. The adrenal cortex function inhibition induced by ETO in CHD children is longer and more serious than that induced by DEX (if any) during the preoperative period.

Ionizing radiation and autoimmunity: Induction of autoimmune disease in mice by high dose fractionated total lymphoid irradiation and its prevention by inoculating normal T cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sakaguchi, N.; Sakaguchi, S.; Miyai, K.

1992-11-01

Ionizing radiation can functionally alter the immune system and break self-tolerance. High dose (42.5 Gy), fractionated (2.5 Gy 17 times) total lymphoid irradiation (TLI) on mice caused various organ-specific autoimmune diseases, such as gastritis, thyroiditis, and orchitis, depending on the radiation dosages, the extent of lymphoid irradiation, and the genetic background of the mouse strains. Radiation-induced tissue damage is not the primary cause of the autoimmune disease because irradiation of the target organs alone failed to elicit the autoimmunity and shielding of the organs from irradiation was unable to prevent it. In contrast, irradiation of both the thymus and themore » peripheral lymphoid organs/tissues was required for efficient induction of autoimmune disease by TLI. TLI eliminated the majority of mature thymocytes and the peripheral T cells for 1 mo, and inoculation of spleen cell, thymocyte, or bone marrow cell suspensions (prepared from syngeneic nonirradiated mice) within 2 wk after TLI effectively prevented the autoimmune development. Depletion of T cells from the inocula abrogated the preventive activity. CD4[sup +] T cells mediated the autoimmune prevention but CD8[sup +] T cells did not. CD4[sup +] T cells also appeared to mediate the TLI-induced autoimmune disease because CD4[sup +] T cells from disease-bearing TLI mice adoptively transferred the autoimmune disease to syngeneic naive mice. Taken together, these results indicate that high dose, fractionated ionizing radiation on the lymphoid organs/tissues can cause autoimmune disease by affecting the T cell immune system, rather than the target self-Ags, presumably by altering T cell-dependent control of self-reactive T cells. 62 refs., 9 figs., 2 tabs.« less

Erufosine, a novel alkylphosphocholine, induces apoptosis in CLL through a caspase-dependent pathway.

PubMed

Königs, Sonja Katharina; Pallasch, Christian Philipp; Lindner, Lars Hartwin; Schwamb, Janine; Schulz, Alexandra; Brinker, Reinhild; Claasen, Julia; Veldurthy, Aditya; Eibl, Hansjoerg; Hallek, Michael; Wendtner, Clemens-Martin

2010-08-01

The alkylphosphocholine (APC) erufosine is a synthetic phospholipid analogue with antineoplastic activity. APC are known to interact with lipid metabolism and modulate cellular signaling pathways, particularly the phosphorylation of Akt. Here, in primary CLL cells induction of apoptosis was detected with an IC50 of 22muM whereas healthy donor PBMC were less sensitive towards erufosine. Treatment with erufosine caused dose-dependent cleavage of PARP, co-incubation with caspase inhibitor z-VAD almost completely abrogated the cytotoxic effect of erufosine indicating a caspase-dependent mechanism of erufosine. Erufosine was shown to induce apoptosis in primary CLL cells and merits further investigation regarding therapeutic options in CLL. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

2′,4′-dihydroxychalcone, a flavonoid isolated from Herba oxytropis, suppresses PC-3 human prostate cancer cell growth by induction of apoptosis

PubMed Central

SHENG, YUQING; ZOU, MINGCHANG; WANG, YAN; LI, QIHENG

2015-01-01

Natural products are a promising source for the development of novel cancer therapies, due to their potential effectiveness and low toxicity profiles. As a main component of Herba oxytropis, 2′,4′-dihydroxychalcone (TFC) is known to demonstrate anti-tumor activity in vitro. In the present study, TFC was found to potently inhibit proliferation and induce apoptosis in PC-3 human prostate cancer cells in a dose-dependent manner. The results demonstrated that the induction of apoptosis is associated with cell cycle arrest at the G0/G1 phase and activation of caspase-3/-7. Additional mechanistic studies of two biomarkers, phosphatase and tensin homolog (PTEN) and cyclin-dependent kinase inhibitor 1B (p27Kip1), in prostate cancer revealed that TFC treatment significantly upregulated the expression of PTEN and p27Kip1. The findings of the present study indicate that TFC-induced apoptosis in PC-3 cells via upregulation of PTEN and p27Kip1, which results in cell cycle arrest in G0/G1 phase, activation of caspase-3/-7 and induction of apoptosis. Therefore, TFC may be a potential compound for human prostate cancer therapy. PMID:26788200

On the mechanism of Cr (VI)-induced carcinogenesis: dose dependence of uptake and cellular responses.

PubMed

Liu, K; Husler, J; Ye, J; Leonard, S S; Cutler, D; Chen, F; Wang, S; Zhang, Z; Ding, M; Wang, L; Shi, X

2001-06-01

Cr (VI) compounds are widely used industrial chemicals and are recognized human carcinogens. The mechanisms of carcinogenesis associated with these compounds remain to be investigated. The present study focused on dose-dependence of Cr (VI)-induced uptake and cellular responses. The results show that Cr (VI) is able to enter the cells (human lung epithelial cell line A549) at low concentration (< 10 microM) and that the Cr (VI) uptake appears to be a combination of saturable transport and passive diffusion. Electron spin resonance (ESR) trapping measurements showed that upon stimulation with Cr (VI), A549 cells were able to generate reactive oxygen species (ROS). The amount of ROS generated depended on the Cr (VI) concentration. ROS generation involved NADPH-dependent flavoenzymes. Cr (VI) affected the following cellular parameters in a dose-dependent manner, (a) activation of nuclear transcription factors NF-kappaB, and p53, (b) DNA damage, (c) induction of cell apoptosis, and (d) inhibition of cell proliferation. The activation of transcription factors was assessed by electrophoretic mobility shift assay and western blot analysis, DNA damage by single cell gel electrophoresis assay, cell apoptosis by DNA fragmentation assay, and cell proliferation by a non-radioactive ELISA kit. At the concentration range used in the present study, no thresholds were found in all of these cell responses to Cr (VI). The results may guide further research to better understand and evaluate the risk of Cr (VI)-induced carcinogenesis at low levels of exposure.

Comparative Analysis of the Relationship between Trichloroethylene Metabolism and Tissue-Specific Toxicity among Inbred Mouse Strains: Liver Effects

PubMed Central

Yoo, Hong Sik; Bradford, Blair U.; Kosyk, Oksana; Shymonyak, Svitlana; Uehara, Takeki; Collins, Leonard B.; Bodnar, Wanda M.; Ball, Louise M.; Gold, Avram; Rusyn, Ivan

2014-01-01

Trichloroethylene (TCE) is a widely used organic solvent. Although TCE is classified as carcinogenic to humans, substantial gaps remain in our understanding of inter-individual variability in TCE metabolism and toxicity, especially in the liver. We tested a hypothesis that amounts of oxidative metabolites of TCE in mouse liver are associated with liver-specific toxicity. Oral dosing with TCE was conducted in sub-acute (600 mg/kg/d; 5 days; 7 inbred mouse strains) and sub-chronic (100 or 400 mg/kg/d; 1, 2, or 4 weeks; 2 inbred mouse strains) designs. We evaluated the quantitative relationship between strain-, dose-, and time-dependent formation of TCE metabolites from cytochrome P450-mediated oxidation [trichloroacetic acid (TCA), dichloroacetic acid (DCA), and trichloroethanol] and glutathione conjugation [S-(1,2-dichlorovinyl)-L-cysteine and S-(1,2-dichlorovinyl)glutathione] in serum and liver, and various liver toxicity phenotypes. In sub-acute study, inter-strain variability in TCE metabolite amounts was observed in serum and liver. No induction of Cyp2e1 protein levels in liver was detected. Serum and liver levels of TCA and DCA were correlated with increased transcription of peroxisome proliferator-marker genes Cyp4a10 and Acox1, but not with degree of induction in hepatocellular proliferation. In sub-chronic study, serum and liver levels of oxidative metabolites gradually decreased over time despite continuous dosing. Liver protein levels of Cyp2e1, Adh and Aldh2 were unaffected by treatment with TCE. While the magnitude of induction of peroxisome proliferator-marker genes also declined, hepatocellular proliferation increased. This study offers a unique opportunity to provide a scientific data-driven rationale for some of the major assumptions in human health assessment of TCE. PMID:25424544

Pharmacokinetics and Pharmacodynamics of Fluconazole for Cryptococcal Meningoencephalitis: Implications for Antifungal Therapy and In Vitro Susceptibility Breakpoints

PubMed Central

Sudan, Ajay; Livermore, Joanne; Howard, Susan J.; Al-Nakeeb, Zaid; Sharp, Andrew; Goodwin, Joanne; Gregson, Lea; Warn, Peter A.; Felton, Tim W.; Perfect, John R.; Harrison, Thomas S.

2013-01-01

Fluconazole is frequently the only antifungal agent that is available for induction therapy for cryptococcal meningitis. There is relatively little understanding of the pharmacokinetics and pharmacodynamics (PK-PD) of fluconazole in this setting. PK-PD relationships were estimated with 4 clinical isolates of Cryptococcus neoformans. MICs were determined using Clinical and Laboratory Standards Institute (CLSI) methodology. A nonimmunosuppressed murine model of cryptococcal meningitis was used. Mice received two different doses of fluconazole (125 mg/kg of body weight/day and 250 mg/kg of body weight/day) orally for 9 days; a control group of mice was not given fluconazole. Fluconazole concentrations in plasma and in the cerebrum were determined using high-performance liquid chromatography (HPLC). The cryptococcal density in the brain was estimated using quantitative cultures. A mathematical model was fitted to the PK-PD data. The experimental results were extrapolated to humans (bridging study). The PK were linear. A dose-dependent decline in fungal burden was observed, with near-maximal activity evident with dosages of 250 mg/kg/day. The MIC was important for understanding the exposure-response relationships. The mean AUC/MIC ratio associated with stasis was 389. The results of the bridging study suggested that only 66.7% of patients receiving 1,200 mg/kg would achieve or exceed an AUC/MIC ratio of 389. The potential breakpoints for fluconazole against Cryptococcus neoformans follow: susceptible, ≤2 mg/liter; resistant, >2 mg/liter. Fluconazole may be an inferior agent for induction therapy because many patients cannot achieve the pharmacodynamic target. Clinical breakpoints are likely to be significantly lower than epidemiological cutoff values. The MIC may guide the appropriate use of fluconazole. If fluconazole is the only option for induction therapy, then the highest possible dose should be used. PMID:23571544

A Double-Blind, Double-Dummy, Flexible-Design Randomized Multicenter Trial: Early Safety of Single- Versus Divided-Dose Rabbit Anti-Thymocyte Globulin Induction in Renal Transplantation.

PubMed

Stevens, R B; Wrenshall, L E; Miles, C D; Farney, A C; Jie, T; Sandoz, J P; Rigley, T H; Osama Gaber, A

2016-06-01

A previous nonblinded, randomized, single-center renal transplantation trial of single-dose rabbit anti-thymocyte globulin induction (SD-rATG) showed improved efficacy compared with conventional divided-dose (DD-rATG) administration. The present multicenter, double-blind/double-dummy STAT trial (Single dose vs. Traditional Administration of Thymoglobulin) evaluated SD-rATG versus DD-rATG induction for noninferiority in early (7-day) safety and tolerability. Ninety-five patients (randomized 1:1) received 6 mg/kg SD-rATG or 1.5 mg/kg/dose DD-rATG, with tacrolimus-mycophenolate maintenance immunosuppression. The primary end point was a composite of fever, hypoxia, hypotension, cardiac complications, and delayed graft function. Secondary end points included 12-month patient survival, graft survival, and rejection. Target enrollment was 165 patients with an interim analysis scheduled after 80 patients. Interim analysis showed primary end point noninferiority of SD-rATG induction (p = 0.6), and a conditional probability of <1.73% of continued enrollment producing a significant difference (futility analysis), leading to early trial termination. Final analysis (95 patients) showed no differences in occurrence of primary end point events (p = 0.58) or patients with no, one, or more than one event (p = 0.81), or rejection, graft, or patient survival (p = 0.78, 0.47, and 0.35, respectively). In this rigorously blinded trial in adult renal transplantation, we have shown SD-rATG induction to be noninferior to DD-rATG induction in early tolerability and equivalent in 12-month safety. (Clinical Trials.gov #NCT00906204.). © Copyright 2016 The Authors. American Journal of Transplantation published by Wiley Periodicals, Inc. on behalf of the American Society of Transplantation and the American Society of Transplant Surgeons.

Antioxidant and anticancer activity of Artemisia princeps var. orientalis extract in HepG2 and Hep3B hepatocellular carcinoma cells.

PubMed

Choi, Eun-Jeong; Kim, Gun-Hee

2013-10-01

The aim of the present study was to investigate antioxidant and the anticancerigen activity of a methanol extract from Artemisia princeps var. orientalis (APME), a well-known traditional herbal medicine in Asia, in hepatocellular cancer cells. To evaluate the antioxidant activity of APME, reactive oxygen species (ROS) and the antioxidant enzymes, superoxide dismutase (SOD) and catalase were investigated in HepG2 cells exposed to APME (5, 100, and 200 µg/mL) for 72 h. Then, to evaluate the anticancer activity of APME, we investigated the proliferation and apoptosis induction of HepG2 and Hep3B cells exposed to APME (1-200 µg/mL) for 24, 48, and 72 h. APME dose-dependently reduced the generation of ROS in the presence of H2O2 compared with control cells. Furthermore, it increased catalase and SOD activity. Moreover, APME inhibited cell proliferation in a dose- and time-dependent manner, but at concentrations lower than 100 µg/mL, the inhibition was less dose-dependent than time-dependent. HepG2 and Hep3B cells exposed to 5, 100, and 200 µg/mL APME for 72 h underwent cell cycle arrest and apoptosis. Exposure to APME resulted in a significant increase in the number of cells in G1 phase and a decrease in the G2/M phase cell population. In addition, APME induced P53 expression of HepG2 cells in a dose-dependent manner, and played a role in the downregulation of Bcl-2 and upregulation of Bax in both HepG2 and Hep3B cells. These results indicate the potential role of APME as an antioxidant and anticancerigen agent in hepatocarcinoma cell lines.

Ciprofloxacin and Trimethoprim Cause Phage Induction and Virulence Modulation in Staphylococcus aureus

PubMed Central

Goerke, Christiane; Köller, Johanna; Wolz, Christiane

2006-01-01

In Staphylococcus aureus strains of human origin, phages which integrate into the chromosomal gene coding for β-hemolysin (hlb) are widely distributed. Most of them encode accessory virulence determinants such as staphylokinase (sak) or enterotoxins. Here, we analyzed the effects of ciprofloxacin and trimethoprim on phage induction and expression of phage-encoded virulence factors by using isolates from patients with cystic fibrosis for which the induction of hlb-converting phages was demonstrated in vivo (C. Goerke, S. Matias y Papenberg, S. Dasbach, K. Dietz, R. Ziebach, B. C. Kahl, and C. Wolz, J. Infect. Dis. 189:724-734, 2004) as well as a φ13 lysogen of phage-cured strain 8325-4. Treatment of lysogens with subinhibitory concentrations of either antibiotic resulted in (i) delysogenization of strains resembling the isolates picked up after chronic lung infection and (ii) replication of phages in the bacterial host in a dose-dependent manner. Ciprofloxacin treatment resulted in enhanced recA transcription, indicating involvement of the SOS response in phage mobilization. Induction of φ13 was linked to elevated expression of the phage-encoded virulence gene sak, chiefly due to the activation of latent phage promoters. In summary, we could show the induction of hlb-converting phages and a subsequent virulence modulation of the host bacterium by ciprofloxacin and trimethoprim. PMID:16377683

Analysis of the antinociceptive interactions in two-drug combinations of gabapentin, oxcarbazepine and amitriptyline in streptozotocin-induced diabetic mice.

PubMed

Tomić, Maja A; Vucković, Sonja M; Stepanović-Petrović, Radica M; Micov, Ana M; Ugresić, Nenad D; Prostran, Milica S; Bosković, Bogdan

2010-02-25

Antiepileptic and antidepressant drugs are the primary treatments for pain relief in diabetic neuropathy. Combination therapy is a valid approach in pain treatment, where a reduction of doses could reduce side effects and still achieve optimal analgesia. We examined the effects of two-drug combinations of gabapentin, oxcarbazepine, and amitriptyline on nociception in diabetic mice and aimed to determine the type of interaction between components. The nociceptive responses in normal and diabetic mice were assessed by the tail-flick test. The testing was performed before and three weeks after the diabetes induction with streptozotocin (150mg/kg; i.p.), when the antinociceptive effects of gabapentin, oxcarbazepine, amitriptyline and their two-drug combinations were examined. Gabapentin (10-40mg/kg; p.o.) and oxcarbazepine (20-80mg/kg; p.o.) produced a significant, dose-dependent antinociception in diabetic mice while amitriptyline (5-60mg/kg; p.o.) produced weak antinociceptive effect. In normal mice, neither of the drugs produced antinociception. Gabapentin and oxcarbazepine, co-administered in fixed-dose fractions of the ED(50) to diabetic mice, induced significant, dose-dependent antinociception. Isobolographic analysis revealed synergistic interaction. Oxcarbazepine (10-60mg/kg; p.o.)+amitriptyline (5mg/kg; p.o.) and gabapentin (10-30mg/kg; p.o.)+amitriptyline (5mg/kg; p.o.) combinations significantly and dose-dependently reduced nociception in diabetic mice. Analysis of the log dose-response curves for oxcarbazepine or gabapentin in a presence of amitriptyline and oxcarbazepine or gabapentin applied alone, revealed a synergism in oxcarbazepine-amitriptyline and additivity in gabapentin-amitriptyline combination. These findings provide new information about the combination therapy of painful diabetic neuropathy and should be explored further in patients with diabetic neuropathy.

Elucidating Rifampin’s Inducing and Inhibiting Effects on Glyburide Pharmacokinetics and Blood Glucose in Healthy Volunteers: Unmasking the Differential Effect of Enzyme Induction and Transporter Inhibition for a Drug and Its Primary Metabolite

PubMed Central

Zheng, HX; Huang, Y; Frassetto, LA; Benet, LZ

2013-01-01

The effects of single doses of intravenous ciprofloxacin and rifampin, multiple doses of rifampin, on glyburide exposure and effect on blood glucose levels in 9 healthy volunteers were investigated. The single intravenous dose of rifampin significantly increased the AUCs of glyburide and metabolite. Blood glucose levels dropped significantly in comparison to when glyburide was dosed alone. Multiple doses of rifampin induced liver enzymes leading to a marked decrease in glyburide exposure and in blood glucose measurements. When intravenous rifampin was given after multiple doses of rifampin, the inhibition of hepatic uptake transporters masked the induction effect, however, relative changes in AUC for glyburide and its hydroxyl metabolite were the same as that seen under non-induced conditions. The studies reported here demonstrate how measurements of both the parent drug and its primary metabolite are useful in unmasking simultaneous drug-drug induction and inhibition effects and characterizing enzymatic versus transporter mechanisms. PMID:18843263

Elucidating rifampin's inducing and inhibiting effects on glyburide pharmacokinetics and blood glucose in healthy volunteers: unmasking the differential effects of enzyme induction and transporter inhibition for a drug and its primary metabolite.

PubMed

Zheng, H X; Huang, Y; Frassetto, L A; Benet, L Z

2009-01-01

The effects of single doses of intravenous (IV) ciprofloxacin and rifampin and of multiple doses of rifampin on glyburide exposure and blood glucose levels were investigated in nine healthy volunteers. A single IV dose of rifampin significantly increased the area under the concentration-time curve (AUC) of glyburide and its metabolite. Blood glucose levels were significantly lower than those observed after dosing with glyburide alone. Multiple doses of rifampin induced an increase in liver enzyme levels, leading to a marked decrease in glyburide exposure and blood glucose levels. When IV rifampin was administered after multiple doses of rifampin, the inhibition of hepatic uptake transporters masked the induction effect; however, the relative changes in AUC for glyburide and its hydroxyl metabolite were similar to those seen under noninduced conditions. The studies reported here demonstrate how measurements of the levels of both the parent drug and its primary metabolite are useful in unmasking simultaneous drug-drug induction and inhibition effects and in characterizing enzymatic vs. transporter mechanisms.

Radiation protocols determine acute graft-versus-host disease incidence after allogeneic bone marrow transplantation in murine models.

PubMed

Schwarte, Sebastian; Bremer, Michael; Fruehauf, Joerg; Sorge, Yanina; Skubich, Susanne; Hoffmann, Matthias W

2007-09-01

Effects of radiation sources used for total body irradiation (TBI) on Graft-versus-Host Disease (GvHD) induction were examined. In a T cell receptor (TCR) transgenic mouse model, single fraction TBI was performed with different radiation devices ((60)Cobalt; (137)Cesium; 6 MV linear accelerator), dose rates (0.85; 1.5; 2.9; 5 Gy/min) and total doses before allogeneic bone marrow transplantation (BMT). Recipients were observed for 120 days. Different tissues were examined histologically. Acute GvHD was induced by a dose rate of 0.85 Gy/min ((60)Cobalt) and a total dose of 9 Gy and injection of 5 x 10(5) lymph node cells plus 5 x 10(6) bone marrow cells. Similar results were obtained using 6 MV linear accelerator- (linac-) photons with a dose rate of 1.5 Gy/min and 0.85 Gy/min, a total dose of 9.5 Gy and injection of same cell numbers. TBI with (137)Cesium (dose rate: 2.5 Gy/min) did not lead reproducibly to lethal acute GvHD. Experimental TBI in murine models may induce different immunological responses, depending on total energy, total single dose and dose rate. GvHD might also be induced by TBI with low dose rates.

Progesterone induces progesterone receptor gene (PGR) expression via rapid activation of protein kinase pathways required for cooperative estrogen receptor alpha (ER) and progesterone receptor (PR) genomic action at ER/PR target genes.

PubMed

Diep, Caroline H; Ahrendt, Hannah; Lange, Carol A

2016-10-01

Progesterone Receptors (PRs) are critical effectors of estrogen receptor (ER) signaling required for mammary gland development and reproductive proficiency. In breast and reproductive tract malignancies, PR expression is a clinical prognostic marker of ER action. While estrogens primarily regulate PR expression, other factors likely contribute to a dynamic range of receptor expression across diverse tissues. In this study, we identified estrogen-independent but progestin (R5020)-dependent regulation of ER target genes including PGR in ER+/PR+ cancer cell lines. R5020 (10nM-10μM range) induced dose-dependent PR mRNA and protein expression in the absence of estrogen but required both PR and ERα. Antagonists of either PR (RU486, onapristone) or ERα (ICI 182,780) attenuated R5020 induction of TFF1, CTSD, and PGR. Chromatin immunoprecipitation (ChIP) assays performed on ER+/PR+ cells demonstrated that both ERα and PR were recruited to the same ERE/Sp1 site-containing region of the PGR proximal promoter in response to high dose progestin (10μM). Recruitment of ERα and PR to chromatin and subsequent PR mRNA induction were dependent upon rapid activation of MAPK/ERK and AKT; inhibition of these kinase pathways via U0126 or LY294002 blocked these events. Overall, we have identified a novel mechanism of ERα activation initiated by rapid PR-dependent kinase pathway activation and associated with phosphorylation of ERα Ser118 for estrogen-independent but progestin-dependent ER/PR cross talk. These studies may provide insight into mechanisms of persistent ER-target gene expression during periods of hormone (i.e. estrogen) ablation and suggest caution following prolonged treatment with aromatase or CYP17 inhibitors (i.e. contexts when progesterone levels may be abnormally elevated). Copyright © 2016 Elsevier Inc. All rights reserved.

Phase I Trial Using Induction Ciplatin, Docetaxel, 5-FU and Erlotinib Followed by Cisplatin, Bevacizumab and Erlotinib With Concurrent Radiotherapy for Advanced Head and Neck Cancer.

PubMed

Ahn, Peter H; Machtay, Mitchell; Anne, Pramila R; Cognetti, David; Keane, William M; Wuthrick, Evan; Dicker, Adam P; Axelrod, Rita S

2018-05-01

Bevacizumab (avastin) and erlotinib (tarceva) had shown early clinical activity against head and neck cancer (HNC). We initiated a phase I trial of induction cisplatin, docetaxel, 5-fluorouracil and erlotinib (TPF-E) followed by cisplatin, bevacizumab and erlotinib (PA-E) with radiotherapy (XRT) for advanced HNC. The goal was to determine maximum tolerated erlotinib dose. Eligible patients had stage IVA or higher HNC with good performance status, hematologic, and renal reserve. Two cycles of induction TPF-E were administered. XRT was administered with concurrent weekly cisplatin and bevacizumab every 2 weeks. Initial erlotinib dose was 50 mg daily from start of induction chemotherapy until radiotherapy completion. Erlotinib dose escalations to 100 and 150 mg were planned. Thirteen patients with previously untreated locoregional disease (11 patients) or oligometastatic (2 patients) HNC were enrolled. Totally, 11 of 13 patients completed XRT as planned. Four of 8 patients in cohort 1 (erlotinib 50 mg), 3 of 4 patients in cohort 2 (100 mg), and 0 of 1 patients in cohort 3 (150 mg) completed the regimen. Two patients had significant gastrointestinal complications (bleeding and perforation), and 1 had dose-limiting diarrhea. Maximum tolerated dose was reached at 50 mg erlotinib. At median 23.4 months follow-up, 5 patients (38%) have no evidence of disease, and 2 (15%) have stable but measurable disease. Erlotinib in combination with induction TPF followed by erlotinib, cisplatin, and bevacizumab with XRT is active but toxic. Gastrointestinal toxicities partly caused high rates of study withdrawal. All doses studied in this protocol caused unexpected toxicities and we do not recommend advancement to phase II.

Comparison of the therapeutic dose of warfarin in HIV-infected and HIV-uninfected patients: a study of clinical practice

PubMed Central

Jackson, B S; Mokoena, T

2017-01-01

Background People infected with HIV are prone to venous thrombosis. Treatment of thrombosis is primarily with warfarin. No studies have addressed the effects of HIV infection on warfarin dose. The aims of this study were to determine whether the therapeutic dose of warfarin and induction time to therapeutic dose in HIV-infected patients differ from that in HIV-uninfected patients. Methods A prospective and retrospective descriptive study of induction time to therapeutic warfarin dose, as well as of ambulant therapeutic warfarin dose, was performed. HIV-infected and HIV-uninfected patients being treated after deep venous thrombosis with or without pulmonary embolism were compared. Sex and use of antiretroviral drugs (ARVs) were also compared in the groups. Results 234 patients were entered into the study. Induction time to therapeutic warfarin dose did not differ between the 2 groups. The mean therapeutic dose of warfarin was higher in the HIV-infected than the HIV-uninfected group: 6.06 vs 5.72 mg/day, but this was not statistically significant (p=0.29). There was no difference in therapeutic warfarin dose between ARV-naïve groups—HIV-uninfected and HIV-infected patients not on ARVs. Conclusions There appears to be little effect of HIV infection on warfarin dosing. Warfarin therapy should be administered conventionally in HIV-infected patients. PMID:28179414

Suppressive effects of chlorophyllin on mutagen-induced umu C gene expression in Salmonella typhimurium (TA 1535/pSK 1002) and tumor promoter-dependent ornithine decarboxylase induction in BALB/c 3T3 fibroblast cells.

PubMed

Okai, Y; Higashi-Okai, K; Yano, Y; Otani, S

1996-08-01

The potentially protective role of chlorophyllin, the sodium and copper salt of chlorophyll a against the initiation and promotion stages in carcinogenesis was studied by in vitro short-term assays. Chlorophyllin showed a dose-dependent suppressive effect on 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indol (Trp-P-1)-induced umu C gene expression of Salmonella typhimurium (TA 1535/pSK 1002) in the presence of metabolizing enzyme mixture. The similar inhibitory effect of chlorophyllin was detected in mitomycin C (MMC)-dependent umu C gene expression in the absence of metabolizing enzyme mixture. Furthermore chlorophyllin also exhibited a dose-dependent inhibition on 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced ornithine decarboxylase (ODC) activity of 3T3 fibroblast cells at the same concentrations. However, when chlorophyll a isolated from Japanese tea leaves was applied on the same assay systems as a comparative experiment, chlorophyll a showed much weaker activity compared with that of chlorophyllin. The significance of this finding is discussed from the viewpoint of the protective role of chlorophyllin against carcinogenesis.

Nanosilica induced dose-dependent cytotoxicity and cell type-dependent multinucleation in HepG2 and L-02 cells

NASA Astrophysics Data System (ADS)

Yu, Yongbo; Duan, Junchao; Li, Yang; Yu, Yang; Hu, Hejing; Wu, Jing; Zhang, Yannan; Li, Yanbo; CaixiaGuo; Zhou, Xianqing; Sun, Zhiwei

2016-11-01

The prevalent exposure to nanosilica gained concerns about health effects of these particles on human beings. Although nanosilica-induced multinucleation has been confirmed previously, the underlying mechanism was still not clear; this study was to investigate the origination of multinucleated cells caused by nanosilica (62 nm) in both HepG2 and L-02 cells. Cell viability and cellular uptake was determined by MTT assay and transmission electron microscope (TEM), respectively. Giemsa staining was applied to detect multinucleation. To clarify the origination of multinucleated cells, fluorescent probes, PKH26 and PKH67, time-lapse observation were further conducted by confocal microscopy. Results indicated that nanosilica particles were internalized into cells and induced cytotoxicity in a dose-dependent manner. Quantification analysis showed that nanosilica significantly increased the rates of binucleated and multinucleated cells, which suggested mitotic catastrophe induction. Moreover, dynamic visualization verified that multinucleation resulted from cell fusion in HepG2 cells not in L-02 cells after nanosilica exposure, suggesting cell type-dependent multinucleation formation. Both multinucleation and cell fusion were involved in genetic instability, which emphasized the significance to explore the multinucleation induced by nanosilica via environmental, occupational and consumer product exposure.

Cellular and molecular analysis of mutagenesis induced by charged particles of defined linear energy transfer.

PubMed

Zhu, L X; Waldren, C A; Vannias, D; Hei, T K

1996-03-01

Mutation induction by charged particles of defined linear energy transfer (LET) and gamma rays was scored using human-hamster hybrid AL cells. The LET values for charged particles accelerated at the Radiological Research Accelerator Facility ranged from 10 keV/microm protons to 150 keV/microm 4He ions. The induced mutant fractions at both the S1 and HGPRT loci were dependent on the dose and LET. In addition, for each dose examined, the mutant yield at the S1 locus was 30-60 fold higher than at the corresponding HGPRT locus. To determine whether the mutation spectrum was comparably dependent on dose and LET, independent S1- and HGPRT- mutants induced by 150 keV/microm 4He ions and gamma rays were isolated, and their DNA was analyzed by both Southern blotting and multiplex PCR methods. While the majority of radiation-induced mutants showed deletions of varying sizes, the relative percentage of large deletions was found to be related to both the dose and LET of the radiation examined. Using a mutation system that can detect multilocus changes, results of the present study show that radiation-induced chromosomal loss can be in the millions of base pairs.

Cellular and molecular analysis of mutagenesis induced by charged particles of defined linear energy transfer

NASA Technical Reports Server (NTRS)

Zhu, L. X.; Waldren, C. A.; Vannias, D.; Hei, T. K.; Chatterjee, A. (Principal Investigator)

1996-01-01

Mutation induction by charged particles of defined linear energy transfer (LET) and gamma rays was scored using human-hamster hybrid AL cells. The LET values for charged particles accelerated at the Radiological Research Accelerator Facility ranged from 10 keV/microm protons to 150 keV/microm 4He ions. The induced mutant fractions at both the S1 and HGPRT loci were dependent on the dose and LET. In addition, for each dose examined, the mutant yield at the S1 locus was 30-60 fold higher than at the corresponding HGPRT locus. To determine whether the mutation spectrum was comparably dependent on dose and LET, independent S1- and HGPRT- mutants induced by 150 keV/microm 4He ions and gamma rays were isolated, and their DNA was analyzed by both Southern blotting and multiplex PCR methods. While the majority of radiation-induced mutants showed deletions of varying sizes, the relative percentage of large deletions was found to be related to both the dose and LET of the radiation examined. Using a mutation system that can detect multilocus changes, results of the present study show that radiation-induced chromosomal loss can be in the millions of base pairs.

Tolerance to Acetaminophen Hepatotoxicity in the Mouse Model of Autoprotection is Associated with Induction of Flavin-containing Monooxygenase-3 (FMO3) in Hepatocytes

EPA Science Inventory

Acetaminophen (APAP) pretreatment with a low hepatotoxic dose in mice results in resistance to a second, higher dose of APAP (APAP autoprotection). Recent microarray work by our group showed a drastic induction of liver flavin containing monooxygenase-3 (Fmo3) mRNA expression in...

Induction and transfer of resistance to poisoning by Amorimia pubiflora in sheep with non-toxic doses of the plant and ruminal content

USDA-ARS?s Scientific Manuscript database

Amorimia pubiflora (Malpighiaceae), which contains sodium monofluoroacetate (MFA) is the main cause of “sudden death” in cattle in the Brazilian state of Mato Grosso. This research investigated the induction of resistance to the poisoning in sheep by the continuous administration of non-toxic doses ...

Tumorigenic action of beta, proton, alpha and electron radiation on the rat skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burns, F.J.

1980-01-01

Rat skin is utilized as a model system for studying dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light and polycyclic aromatic hydrocarbons. Molecular lesions in the DNA of the epidermis, including strand breaks and thymine dimers, are measured and compared to the temporal and dose related aspects of tumor induction. The induction and repair kinetics of molecular lesions are compared to split dose recovery as modified by sensitizers and type of radition of oncogenic damage.

Health effects in women exposed to low levels of ionizing radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fabrikant, J.I.

1982-06-01

There are three delayed health effects of radiation which appear at the present time to have importance to women in radiation protection. These are: (1) the probability of cancer-induction at low doses and low-dose rates; (2) the consideration of those cancers in women, notably the breast and the thyroid, attributable to radiation exposure; and (3) the probability of induction of developmental abnormalities in the newborn following low-dose exposure in utero. The bases for the concern over these effects are discussed. (ACR)

Protective effect of natural honey against acetic acid-induced colitis in rats.

PubMed

Mahgoub, A A; el-Medany, A H; Hagar, H H; Sabah, D M

2002-01-01

The protective effects of natural honey against acetic acid-induced colitis were investigated in rats. Honey and glucose, fructose, sucrose, maltose mixture were administered, orally and rectally, daily for a period of 4 days. Induction of colitis was done on the third day using 3% acetic acid. Animals were killed on day 4 two hours after administration of the dose and colonic biopsies were taken for macroscopic scoring, histopathological and biochemical studies. Honey dose-dependently afforded protection against acetic acid-induced colonic damage. There was almost 100% protection with the highest dose (5 g/kg) used while glucose, fructose, sucrose, maltose mixture produced no significant protective effect. Also, honey prevented the depletion of the antioxidant enzymes reduced glutathione and catalase and restored the lipid peroxide malondialdehyde towards normal levels. Further studies are required to explore the active ingredients responsible for the antioxidant effect of honey and its therapeutic potential in humans.

Linking embryo toxicity with genotoxic responses in the freshwater snail Physa acuta: single exposure to benzo(a)pyrene, fluoxetine, bisphenol A, vinclozolin and exposure to binary mixtures with benzo(a)pyrene.

PubMed

Sánchez-Argüello, Paloma; Aparicio, Natalia; Fernández, Carlos

2012-06-01

Genotoxic effects on fauna after waterborne pollutant exposure have been demonstrated by numerous research programmes. Less effort has been focused on establishing relationship between genotoxicity and long-term responses at higher levels of biological organization. Taking into account that embryos may be more sensitive indicators of reproductive impairment than alterations in fertility, we have developed two assays in multiwell plates to address correlations between embryo toxicity and genotoxicity. The potential teratogenicity was assessed by analyzing abnormal development and mortality of Physa acuta at embryonic stage. Genotoxicity was measured by the micronucleus (MN) test using embryonic cells. Our results showed that linkage between genotoxicity and embryo toxicity depends on mechanisms of action of compounds under study. Embryo toxic responses showed a clear dose-related tendency whereas no clear dose-dependent effect was observed in micronucleus induction. The higher embryo toxicity was produced by benzo(a)pyrene exposure followed by fluoxetine and bisphenol A. Vinclozolin was the lower embryo toxic compound. Binary mixtures with BaP always resulted in higher embryo toxicity than single exposures but antagonistic effects were observed for MN induction. Benzo(a)pyrene produced the higher MN induction at 0.04 mg/L, which also produced clear embryo toxic effects. Fluoxetine did not induce cytogenetic effects but 0.25mg/L altered embryonic development. Bisphenol A significantly reduced hatchability at 0.5mg/L while MN induction appeared with higher treatments than those that start causing teratogenicity. Much higher concentration of vinclozolin (5mg/L) reduced hatchability and induced maximum MN formation. In conclusion, while validating one biomarker of genotoxicity and employing one ecologically relevant effect, we have evaluated the relative sensitivity of a freshwater mollusc for a range of chemicals. The embryo toxicity test is a starting point for the development of a life cycle test with freshwater snails even for undertaking multigeneration studies focused on transgenerational effects. Copyright © 2012 Elsevier Inc. All rights reserved.

Does intravenous induction dosing among patients undergoing gastrointestinal surgical procedures follow current recommendations: a study of contemporary practice.

PubMed

Akhtar, Shamsuddin; Liu, Jia; Heng, Joseph; Dai, Feng; Schonberger, Robert B; Burg, Matthew M

2016-09-01

It is recommended to correct intravenous induction doses by up to 50% for patients older than 65 years. The objectives were to determine (a) the degree to which anesthesia providers correct induction doses for age and (b) additionally adjust for American Society of Anesthesiologists physical status (ASA-PS) class (severity of illness) and (c) whether postinduction hypotension is more common among patients aged >65. Retrospective chart review. Academic medical center. A total of 1869 adult patients receiving general anesthesia for GI surgical procedures from February 2013 to January 2014. Patients were divided into 3 age groups (age <65, 65-79, ≥80 years) and then further stratified into ASA-PS class (I/II vs III/IV). Multiple pairwise comparisons were conducted using Welch t tests for continuous variables to determine whether dosing was different for the older groups vs the younger group; separate analyses were performed within and across ASA-PS class. This approach was also used to determine differences in mean arterial pressure change in the older groups vs the younger group, whereas the rates of hypotension among different age groups were compared by Cochran-Armitage trend test. No significant decrease in dosing between age groups was observed for fentanyl and midazolam. For propofol, there was a significantly lower dosing for older patients: 17% for patients aged 65-79 and 29% for those aged >80, which was still in less than the recommendations. An inverse relationship was observed between propofol dosing and ASA-PS class, but no consistent relationship was noted for fentanyl and midazolam. There were a significantly larger drop in mean arterial pressure and a greater likelihood of hypotension following induction in patients aged 65-79 years and >80 years as compared with those aged <65 years. This study shows that the administered dose of anesthetic induction agents is significantly higher than that recommended for patients older than 65 years. This failure to age-adjust dose may contribute to hypotensive episodes. Copyright © 2016 Elsevier Inc. All rights reserved.

Induction and repair of DNA double-strand breaks in hippocampal neurons of mice of different age after exposure to 60Co γ-rays in vivo and in vitro

NASA Astrophysics Data System (ADS)

Kozhina, R. A.; Chausov, V. N.; Kuzmina, E. A.; Boreyko, A. V.

2018-04-01

One of the central problems of modern radiobiology is the study of DNA damage induction and repair mechanisms in central nervous system cells, in particular, in hippocampal cells. The study of the regularities of molecular damage formation and repair in the hippocampus cells is of special interest, because these cells, unlike most cells of the central nervous system (CNS), keep proliferative activity, i.e. ability to neurogenesis. Age-related changes in hippocampus play an important role, which could lead to radiosensitivity changes in neurons to the ionizing radiation exposure. Regularities in DNA double-strand breaks (DSB) induction and repair in different aged mice hippocampal cells in vivo and in vitro under the action of γ-rays 60Co were studied with DNA comet-assay. The obtained dose dependences of DNA DSB induction are linear both in vivo and in vitro. It is established that in young animals' cells, the degree of DNA damage is higher than in older animals. It is shown that repair kinetics is basically different for exposure in vivo and in vitro.

Methadone and Metabolites in Hair of Methadone-Assisted Pregnant Women and Their Infants

PubMed Central

Himes, Sarah K; Goodwin, Robert S; Rock, Colleen M; Jones, Hendrée E; Johnson, Rolley E; Wilkins, Diana G; Huestis, Marilyn A

2012-01-01

Methadone is the recommended pharmacotherapy for opioid-dependent pregnant women. The primary aims of this study were to determine whether a dose-concentration relationship exists between cumulative maternal methadone dose, methadone and metabolite concentrations in maternal hair during pregnancy and whether maternal hair methadone and metabolite concentrations predict neonatal outcomes. Materials and Methods Hair specimens were collected monthly from opioid-dependent mothers enrolled in methadone treatment and 4 of their infants. Hair specimens were segmented (3cm), washed (maternal hair only) and analyzed for methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyrroline (EMDP) by liquid chromatography tandem mass spectrometry. Results There was large inter-subject variability and no dose-concentration relationship for cumulative methadone dose and methadone, EDDP, EMDP or total concentrations in hair. For individual women, a positive trend was noted for cumulative methadone dose and methadone and EDDP concentrations in hair. There was a positive linear trend for cumulative methadone dose and EDDP/methadone ratio in maternal hair, perhaps reflecting methadone’s induction of its own metabolism. Maternal methadone concentrations were higher than those in infant hair, and infant EDDP hair concentrations were higher than those in maternal hair. Maternal methadone dose, and methadone and EDDP hair concentrations were not correlated with peak infant neonatal abstinence syndrome (NAS) scores, days to peak NAS, duration of NAS, time to NAS onset, birth length, head circumference or amount of neonatal morphine pharmacotherapy. Maternal cumulative 3rd trimester methadone dose was positively correlated with infant birth weight. Conclusion Methadone and EDDP in pregnant women’s hair are markers of methadone exposure and do not predict total methadone dose, nor neonatal outcomes from in utero methadone exposure. PMID:22495425

Restoration of low-dose digital breast tomosynthesis

NASA Astrophysics Data System (ADS)

Borges, Lucas R.; Azzari, Lucio; Bakic, Predrag R.; Maidment, Andrew D. A.; Vieira, Marcelo A. C.; Foi, Alessandro

2018-06-01

In breast cancer screening, the radiation dose must be kept to the minimum necessary to achieve the desired diagnostic objective, thus minimizing risks associated with cancer induction. However, decreasing the radiation dose also degrades the image quality. In this work we restore digital breast tomosynthesis (DBT) projections acquired at low radiation doses with the goal of achieving a quality comparable to that obtained from current standard full-dose imaging protocols. A multiframe denoising algorithm was applied to low-dose projections, which are filtered jointly. Furthermore, a weighted average was used to inject a varying portion of the noisy signal back into the denoised one, in order to attain a signal-to-noise ratio comparable to that of standard full-dose projections. The entire restoration framework leverages a signal-dependent noise model with quantum gain which varies both upon the projection angle and on the pixel position. A clinical DBT system and a 3D anthropomorphic breast phantom were used to validate the proposed method, both on DBT projections and slices from the 3D reconstructed volume. The framework is shown to attain the standard full-dose image quality from data acquired at 50% lower radiation dose, whereas progressive loss of relevant details compromises the image quality if the dosage is further decreased.

Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adachi, Naoki; Kubota, Yoshitaka, E-mail: kubota-cbu@umin.ac.jp; Kosaka, Kentarou

2015-08-07

Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDRmore » may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings.« less

UVA-induced DNA double-strand breaks result from the repair of clustered oxidative DNA damages

PubMed Central

Greinert, R.; Volkmer, B.; Henning, S.; Breitbart, E. W.; Greulich, K. O.; Cardoso, M. C.; Rapp, Alexander

2012-01-01

UVA (320–400 nm) represents the main spectral component of solar UV radiation, induces pre-mutagenic DNA lesions and is classified as Class I carcinogen. Recently, discussion arose whether UVA induces DNA double-strand breaks (dsbs). Only few reports link the induction of dsbs to UVA exposure and the underlying mechanisms are poorly understood. Using the Comet-assay and γH2AX as markers for dsb formation, we demonstrate the dose-dependent dsb induction by UVA in G1-synchronized human keratinocytes (HaCaT) and primary human skin fibroblasts. The number of γH2AX foci increases when a UVA dose is applied in fractions (split dose), with a 2-h recovery period between fractions. The presence of the anti-oxidant Naringin reduces dsb formation significantly. Using an FPG-modified Comet-assay as well as warm and cold repair incubation, we show that dsbs arise partially during repair of bi-stranded, oxidative, clustered DNA lesions. We also demonstrate that on stretched chromatin fibres, 8-oxo-G and abasic sites occur in clusters. This suggests a replication-independent formation of UVA-induced dsbs through clustered single-strand breaks via locally generated reactive oxygen species. Since UVA is the main component of solar UV exposure and is used for artificial UV exposure, our results shine new light on the aetiology of skin cancer. PMID:22941639

Treatment of primary acute myeloid leukemia: results of a prospective multicenter trial including high-dose cytarabine or stem cell transplantation as post-remission strategy.

PubMed

Brunet, Salut; Esteve, Jordi; Berlanga, Joan; Ribera, Josep M; Bueno, Javier; Martí, Josep M; Bargay, Joan; Guardia, Ramon; Juliá, Antoni; Granena, Albert; Montserrat, Emili; Sierra, Jorge

2004-08-01

To evaluate a regimen of induction and consolidation chemotherapy, followed by a post-remission therapy which depended on age and cytogenetics, in patients with primary acute myeloid leukemia. Two hundred patients up to 60 years old received idarubicin, standard dose cytarabine and etoposide as induction chemotherapy and one consolidation course including intermediate dose cytarabine and mitoxantrone. Subsequently, patients with favorable cytogenetics, [i.e., t(8;21), inv(16)] were scheduled to receive 2 courses of high-dose cytarabine. The remainder were scheduled for allogeneic stem cell transplantation (SCT), if 50 years old or lacking a donor. In patients with favorable cytogenetics the 4-year probabilities of survival and leukemia-free survival (LFS) were 62+/-9% and 41+/-10%, respectively. The results were better in patients with t(8;21). LFS at 4 years in patients 50 years old assigned to auto-SCT had a 4-year LFS of 17+/-9%. Adverse cytogenetics and white blood cell count >or= 20 yen 109/L at diagnosis were associated with lower probability of survival and leukemia-free survival. We confirmed that high-dose cytarabine seems a good option for patients with t(8;21). Autologous and allogeneic SCT led to similar leukemia-free survival in patients

Influence of DNA Repair on Nonlinear Dose-Responses for Mutation

PubMed Central

Johnson, George E.

2013-01-01

Recent evidence has challenged the default assumption that all DNA-reactive alkylating agents exhibit a linear dose-response. Emerging evidence suggests that the model alkylating agents methyl- and ethylmethanesulfonate and methylnitrosourea (MNU) and ethylnitrosourea observe a nonlinear dose-response with a no observed genotoxic effect level (NOGEL). Follow-up mechanistic studies are essential to understand the mechanism of cellular tolerance and biological relevance of such NOGELs. MNU is one of the most mutagenic simple alkylators. Therefore, understanding the mechanism of mutation induction, following low-dose MNU treatment, sets precedence for weaker mutagenic alkylating agents. Here, we tested MNU at 10-fold lower concentrations than a previous study and report a NOGEL of 0.0075 µg/ml (72.8nM) in human lymphoblastoid cells, quantified through the hypoxanthine (guanine) phosphoribosyltransferase assay (OECD 476). Mechanistic studies reveal that the NOGEL is dependent upon repair of O6-methylguanine (O6MeG) by the suicide enzyme O6MeG-DNA methyltransferase (MGMT). Inactivation of MGMT sensitizes cells to MNU-induced mutagenesis and shifts the NOGEL to the left on the dose axis. PMID:23288051

Influence of DNA repair on nonlinear dose-responses for mutation.

PubMed

Thomas, Adam D; Jenkins, Gareth J S; Kaina, Bernd; Bodger, Owen G; Tomaszowski, Karl-Heinz; Lewis, Paul D; Doak, Shareen H; Johnson, George E

2013-03-01

Recent evidence has challenged the default assumption that all DNA-reactive alkylating agents exhibit a linear dose-response. Emerging evidence suggests that the model alkylating agents methyl- and ethylmethanesulfonate and methylnitrosourea (MNU) and ethylnitrosourea observe a nonlinear dose-response with a no observed genotoxic effect level (NOGEL). Follow-up mechanistic studies are essential to understand the mechanism of cellular tolerance and biological relevance of such NOGELs. MNU is one of the most mutagenic simple alkylators. Therefore, understanding the mechanism of mutation induction, following low-dose MNU treatment, sets precedence for weaker mutagenic alkylating agents. Here, we tested MNU at 10-fold lower concentrations than a previous study and report a NOGEL of 0.0075 µg/ml (72.8nM) in human lymphoblastoid cells, quantified through the hypoxanthine (guanine) phosphoribosyltransferase assay (OECD 476). Mechanistic studies reveal that the NOGEL is dependent upon repair of O(6)-methylguanine (O(6)MeG) by the suicide enzyme O(6)MeG-DNA methyltransferase (MGMT). Inactivation of MGMT sensitizes cells to MNU-induced mutagenesis and shifts the NOGEL to the left on the dose axis.

Induction of an adaptive response in human blood lymphocytes exposed to radiofrequency fields: influence of the universal mobile telecommunication system (UMTS) signal and the specific absorption rate.

PubMed

Zeni, Olga; Sannino, Anna; Romeo, Stefania; Massa, Rita; Sarti, Maurizio; Reddy, Abishek B; Prihoda, Thomas J; Vijayalaxmi; Scarfì, Maria Rosaria

2012-08-30

The induction of an adaptive response (AR) was examined in human peripheral blood lymphocytes exposed to non-ionizing radiofrequency fields (RF). Cells from nine healthy human volunteers were stimulated for 24h with phytohaemagglutinin and then exposed for 20h to an adaptive dose (AD) of a 1950MHz RF UMTS (universal mobile telecommunication system) signal used for mobile communications, at different specific absorption rates (SAR) of 1.25, 0.6, 0.3, and 0.15W/kg. This was followed by treatment of the cells at 48h with a challenge dose (CD) of 100ng/ml mitomycin C (MMC). Lymphocytes were collected at the end of the 72h total culture period. The cytokinesis-block method was used to record the frequency of micronuclei (MN) as genotoxicity end-point. When lymphocytes from six donors were pre-exposed to RF at 0.3W/kg SAR and then treated with MMC, these cells showed a significant reduction in the frequency of MN, compared with the cells treated with MMC alone; this result is indicative of induction of AR. The results from our earlier study indicated that lymphocytes that were stimulated for 24h, exposed for 20h to a 900MHz RF GSM (global system for mobile communication) signal at 1.25W/kg SAR and then treated with 100ng/ml MMC, also exhibited AR. These overall data suggest that the induction of AR depends on RF frequency, type of the signal and SAR. Further characterization of RF-induced AR is in progress. Copyright © 2012 Elsevier B.V. All rights reserved.

Dose requirements of alfentanil to eliminate autonomic responses during rapid-sequence induction with thiopental 4 mg/kg and rocuronium 0.6 mg/kg.

PubMed

Abou-Arab, Mohammad H; Rostrup, Morten; Heier, Tom

2016-12-01

Opioids are integral part of anesthesia induction, but information on optimal dosing is limited. We aimed to determine doses of alfentanil needed to eliminate increases in 5 autonomic response variables (plasma concentrations of epinephrine, norepinephrine and vasopressin, arterial blood pressure [ABP], and heart rate) during rapid-sequence induction of anesthesia with thiopental 4 mg/kg and rocuronium 0.6 mg/kg. Prospective, randomized, observer-blinded, interventional clinical study. Large academic institution. Eighty-four healthy patients, aged 18 to 55 years, received 1 of 7 assessor-blinded doses of alfentanil (0, 10, 20, 30, 40, 50, and 60 μg/kg) together with thiopental 4 mg/kg and rocuronium 0.6 mg/kg, administered in rapid succession (15 seconds). Laryngoscopy was initiated 40 seconds after rocuronium, and tracheal intubation was concluded within 15 seconds thereafter. An indwelling radial artery catheter was used for hemodynamic monitoring and blood sampling. Relationships between alfentanil dose and response variables were tested with linear regression, and the influence of covariates (sex, body weight, and age) was determined. Alfentanil dose needed to prevent increases in ABP >10% above baseline with 95% probability was estimated with logistic regression. Significant relationships were determined between alfentanil dose and response variables. Clinically interesting influence of covariates was not found. Alfentanil 55 μg/kg was needed to prevent increases in ABP postintubation >10% above baseline with 95% probability. One individual needed a bolus of vasopressor postintubation. Optimal control of autonomic responses during rapid-sequence induction was achieved with clinically relevant doses of alfentanil in healthy patients anesthetized with thiopental 4 mg/kg and rocuronium 0.6 mg/kg. Copyright © 2016 Elsevier Inc. All rights reserved.

A phase I window, dose escalating and safety trial of metformin in combination with induction chemotherapy in relapsed refractory acute lymphoblastic leukemia: Metformin with induction chemotherapy of vincristine, dexamethasone, PEG-asparaginase, and doxorubicin.

PubMed

Trucco, Matteo; Barredo, Julio C; Goldberg, John; Leclerc, Gilles M; Hale, Gregory A; Gill, Jonathan; Setty, Bhuvana; Smith, Tiffany; Lush, Richard; Lee, Jae K; Reed, Damon R

2018-06-01

Acute lymphoblastic leukemia (ALL) remains a major cause of death in children. AMP-activated protein kinase (AMPK) affects the unfolded protein response (UPR), leading to increased vulnerability to endoplasmic reticulum (ER) stress in ALL cells. In vitro, metformin causes ALL cell death via AMPK-mediated inhibition of the UPR. It was evaluated whether ER stress could be induced in relapsed ALL through a phase I study investigating the safety and feasibility of metformin in combination with relapse induction chemotherapy. Metformin was administered twice daily for 28 days in addition to vincristine, dexamethasone, PEG-asparaginase and doxorubicin (VXLD). Dose escalation of metformin was evaluated using a 3+3 design. Pharmacokinetics (PK), pharmacodynamic (PD) evaluation of the AMPK and ER stress/UPR pathways, and treatment response were assessed. Fourteen patients were enrolled; all were evaluable for toxicity. The recommended phase 2 dose (RP2D) was Dose level 2, 1,000 mg/m 2 /day. A single dose-limiting toxicity (DLT), hypoglycemia with acidosis, was observed at the RP2D and two DLTs, diarrhea and acidosis, were observed at Dose Level 3. Nine patients were evaluable for response as defined by the protocol, receiving at least 85% of planned metformin doses. Five complete remissions, one partial response, and one stable disease were observed. PD evaluation showed induction of ER stress, activation of AMPK, and inhibition of the UPR. The VXLD with metformin was tolerable with a RP2D for metformin of 1,000 mg/m 2 /day and yielded responses in a heavily pretreated population. ER stress was induced and toxicities attributable to metformin occurred in all dose levels. © 2018 Wiley Periodicals, Inc.

Evaluation of the brain anaesthesia response monitor during anaesthesia for cardiac surgery: a double-blind, randomised controlled trial using two doses of fentanyl.

PubMed

Shoushtarian, Mehrnaz; McGlade, Desmond P; Delacretaz, Louis J; Liley, David T J

2016-12-01

The brain anaesthesia response (BAR) monitor uses a method of EEG analysis, based on a model of brain electrical activity, to monitor the cerebral response to anaesthetic and sedative agents via two indices, composite cortical state (CCS) and cortical input (CI). It was hypothesised that CCS would respond to the hypnotic component of anaesthesia and CI would differentiate between two groups of patients receiving different doses of fentanyl. Twenty-five patients scheduled to undergo elective first-time coronary artery bypass graft surgery were randomised to receive a total fentanyl dose of either 12 μg/kg (fentanyl low dose, FLD) or 24 μg/kg (fentanyl moderate dose, FMD), both administered in two divided doses. Propofol was used for anaesthesia induction and pancuronium for intraoperative paralysis. Hemodynamic management was protocolised using vasoactive drugs. BIS, CCS and CI were simultaneously recorded. Response of the indices (CI, CCS and BIS) to propofol and their differences between the two groups at specific points from anaesthesia induction through to aortic cannulation were investigated. Following propofol induction, CCS and BIS but not CI showed a significant reduction. Following the first dose of fentanyl, CI, CCS and BIS decreased in both groups. Following the second dose of fentanyl, there was a significant reduction in CI in the FLD group but not the FMD group, with no significant change found for BIS or CCS in either group. The BAR monitor demonstrates the potential to monitor the level of hypnosis following anaesthesia induction with propofol via the CCS index and to facilitate the titration of fentanyl as a component of balanced anaesthesia via the CI index.

Mecambridine induces potent cytotoxic effects, autophagic cell death and modulation of the mTOR/PI3K/Akt signaling pathway in HSC-3 oral squamous cell carcinoma cells

PubMed Central

Lin, Na; Li, Zhiping; Wang, Deli; Zheng, Kewen; Wu, Yiyan; Wang, Huiqi

2018-01-01

Plant secondary metabolites including alkaloids, demonstrate a complex diversity in their molecular scaffolds and exhibit tremendous pharmacological potential as anti-cancerous therapeutics. The present study aimed to evaluate the anticancer activity of a natural alkaloid, mecambridine, against human oral squamous cell carcinoma (OSCC). An MTT assay was used to evaluate cytotoxic effects of mecambridine on HSC-3 oral squamous cell carcinoma cells. Effects of mecambridine on autophagy-associated proteins were analyzed by western blotting. Effects on reactive oxygen species (ROS) and mitochondrial membrane potential were assessed by flow cytometry. Results indicated that mecambridine exhibited an IC50 value of 50 µM and exerted its cytotoxic effects in a dose dependent manner on OSCC HSC-3 cells. Furthermore, it was observed that mecambridine decreases cell viability and induces autophagy in a dose-dependent manner. The underlying mechanism for the induction of autophagy was demonstrated to be associated with ROS-mediated alterations in mitochondrial membrane potential and modulation of the mechanistic target of rapamycin/phosphoinositide 3-kinase/protein kinase B (m-TOR/PI3K/Akt) signaling pathway in HSC-3 at the IC50. In conclusion, the present study suggests that mecambridine exhibits substantial anticancer activity against OSCC HSC-3 cells by induction of autophagy and modulates the expression of the mTOR/PI3K/Akt signaling cascade which is considered a potential target pathway for anti-cancer agents. PMID:29422960

Anti-Inflammatory Activity of Butein and Luteolin Through Suppression of NFκB Activation and Induction of Heme Oxygenase-1.

PubMed

Sung, Jeehye; Lee, Junsoo

2015-05-01

Butein and luteolin are members of the flavonoid family, which displays a variety of biological activities. In this study, we demonstrated that butein and luteolin exert anti-inflammatory activities in RAW264.7 macrophages by inducing heme oxygenase-1 (HO-1) expression. Butein and luteolin dose-dependently attenuated inducible nitric oxide synthase (iNOS) expression, leading to the suppression of iNOS-derived nitric oxide (NO) production. The inhibitory effect of butein on NO production was greater than that of luteolin. Consistent with this finding, butein also showed higher inhibitory effects on lipopolysaccharide (LPS)-induced translocation of nuclear factor κB (NFκB) and NFκB reporter gene activity in macrophages than luteolin. Furthermore, the expression of HO-1 was dose-dependently induced by butein and luteolin treatments in macrophages. Additionally, the anti-inflammatory activities of butein and luteolin involved the induction of HO-1 expression, as confirmed by the zinc protoporphyrin (ZnPP) treatment (HO-1 selective inhibitor) and HO-1 small interfering (si)RNA system. ZnPP-mediated downregulation and siRNA-mediated knockdown of HO-1 significantly abolished the inhibitory effects of butein and luteolin on the production of NO in LPS-induced macrophages. Consequently, butein and luteolin were shown to be effective HO-1 inducers capable of inhibiting macrophage-derived proinflammatory mechanisms. These findings indicate that butein and luteolin are potential therapeutic agents for the treatment of inflammatory diseases.

Oxycodone physical dependence and its oral self-administration in C57BL/6J mice.

PubMed

Enga, Rachel M; Jackson, Asti; Damaj, M Imad; Beardsley, Patrick M

2016-10-15

Abuse of prescription opioids, such as oxycodone, has markedly increased in recent decades. While oxycodone's antinociceptive effects have been detailed in several preclinical reports, surprisingly few preclinical reports have elaborated its abuse-related effects. This is particularly surprising given that oxycodone has been in clinical use since 1917. In a novel oral operant self-administration procedure, C57BL/6J mice were trained to self-administer water before introducing increasing concentrations of oxycodone (0.056-1.0mg/ml) under post-prandial conditions during daily, 3-h test sessions. As the concentration of oxycodone increased, the numbers of deliveries first increased, then decreased in an inverted U-shape fashion characteristic of the patterns of other drugs self-administered during limited access conditions. After post-prandial conditions were removed, self-administration at the highest concentration was maintained suggesting oral oxycodone served as a positive reinforcer. In other mice, using a novel regimen of physical dependence, mice were administered increasing doses of oxycodone (9.0-33.0mg/kg, s.c.) over 9 days, challenged with naloxone (0.1-10.0mg/kg, s.c.), and then observed for 30min. Naloxone dose-dependently increased the observed number of somatic signs of withdrawal, suggesting physical dependence of oxycodone was induced under this regimen. This is the first report demonstrating induction of oral operant self-administration of oxycodone and dose-dependent precipitations of oxycodone withdrawal in C57BL/6J mice. The use of oral operant self-administration as well as the novel physical dependence regimen provides useful approaches to further examine the abuse- and dependence-related effects of this highly abused prescription opioid. Copyright © 2016 Elsevier B.V. All rights reserved.

Cytotoxic activities of Coriolus versicolor (Yunzhi) extract on human leukemia and lymphoma cells by induction of apoptosis.

PubMed

Lau, C B S; Ho, C Y; Kim, C F; Leung, K N; Fung, K P; Tse, T F; Chan, H H L; Chow, M S S

2004-07-02

Coriolus versicolor (CV), also known as Yunzhi, is one of the commonly used Chinese medicinal herbs. Although recent studies have demonstrated its antitumour activities on cancer cells in vitro and in vivo, the exact mechanism is not fully elucidated. Hence, the objective of this study was to examine the in vitro cytotoxic activities of a standardized aqueous ethanol extract prepared from Coriolus versicolor on a B-cell lymphoma (Raji) and two human promyelocytic leukemia (HL-60, NB-4) cell lines using a MTT cytotoxicity assay, and to test whether the mechanism involves induction of apoptosis. Cell death ELISA was employed to quantify the nucleosome production resulting from nuclear DNA fragmentation during apoptosis. The present results demonstrated that CV extract at 50 to 800 microg/ml dose-dependently suppressed the proliferation of Raji, NB-4, and HL-60 cells by more than 90% (p < 0.01), with ascending order of IC50 values: HL-60 (147.3 +/- 15.2 microg/ml), Raji (253.8 +/- 60.7 microg/ml) and NB-4 (269.3 +/- 12.4 microg/ml). The extract however did not exert any significant cytotoxic effect on normal liver cell line WRL (IC50 > 800 microg/ml) when compared with a chemotherapeutic anticancer drug, mitomycin C (MMC), confirming the tumour-selective cytotoxicity. Nucleosome productions in HL-60, NB-4 and Raji cells were significantly increased by 3.6-, 3.6- and 5.6-fold respectively upon the treatment of CV extract, while no significant nucleosome production was detected in extract-treated WRL cells. The CV extract was found to selectively and dose-dependently inhibit the proliferation of lymphoma and leukemic cells possibly via an apoptosis-dependent pathway. Copyright 2004 Elsevier Inc.

A mode of action for induction of liver tumors by Pyrethrins in the rat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Price, Roger J.; Walters, David G.; Finch, John M.

2007-01-15

High doses of Pyrethrins produce liver tumors in female rats. To elucidate the mode of action for tumor formation, the hepatic effects of Pyrethrins have been investigated. Male Sprague-Dawley CD rats were fed diets containing 0 (control) and 8000 ppm Pyrethrins and female rats' diets containing 0, 100, 3000 and 8000 ppm Pyrethrins for periods of 7, 14 and 42 days and 42 days followed by 42 days of reversal. As a positive control, rats were also fed diets containing 1200-1558 ppm sodium Phenobarbital (NaPB) for 7 and 14 days. The treatment of male rats with 8000 ppm Pyrethrins, femalemore » rats with 3000 and 8000 ppm Pyrethrins and both sexes with NaPB resulted in increased liver weights, which were associated with hepatocyte hypertrophy. Hepatocyte replicative DNA synthesis was also increased by treatment with Pyrethrins and NaPB. The treatment of male and female rats with Pyrethrins and NaPB produced significant increases in hepatic microsomal cytochrome P450 (CYP) content and a marked induction of CYP2B-dependent 7-pentoxyresorufin O-depentylase and testosterone 16{beta}-hydroxylase activities. Significant increases were also observed in CYP3A-dependent testosterone 6{beta}-hydroxylase activity. The hepatic effects of Pyrethrins were dose-dependent in female rats with 100 ppm being a no effect level and on cessation of treatment were reversible in both sexes. This study demonstrates that Pyrethrins are mitogenic CYP2B form inducers in rat liver. The mode of action for Pyrethrins-induced rat liver tumor formation appears to be similar to that of NaPB and some other non-genotoxic CYP2B inducers of hepatic xenobiotic metabolism.« less

Once daily vs multiple daily mesalamine therapy for mild to moderate ulcerative colitis: a meta-analysis.

PubMed

Li, W; Zhang, Z-M; Jiang, X-L

2016-07-01

5-Aminosalicylic acid is the first-line drug for mild to moderate ulcerative colitis (UC). The most commonly used 5-aminosalicylic acid is mesalamine. Several systematic reviews have demonstrated that mesalamine is effective in inducing and maintaining remission. Efficacy, safety and adherence to once daily (OD) and multiple daily (MD) dosing of mesalamine for the induction and maintenance of remission in mild to moderate UC were systematically reviewed and compared. PubMed, Embase and the Cochrane Central Register of Controlled Trials were searched from inception to November 2014. Only randomized controlled trials were considered eligible. STATA software (version 12.0) was used to calculate the pooled risk ratios with 95% confidence interval. Seventeen randomized studies containing 5439 patients were identified. No significant differences were noted in comparisons between OD and MD dosing for maintenance and induction of remission. No significant differences were noted in rates of medication adherence or adverse events between OD and MD dosing. With regard to mesalamine suppository, no significant differences were noted for comparisons between dosing regimens and adverse events for induction of remission. OD dose of mesalamine is as effective and safe as MD doses for the induction and maintenance treatment of mild to moderate UC. OD mesalamine given as a suppository can attain the same effect and safety as MD mesalamine in inducing remission of mild to moderate ulcerative colitis. Colorectal Disease © 2016 The Association of Coloproctology of Great Britain and Ireland.

Does a hypnosis session reduce the required propofol dose during closed-loop anaesthesia induction?: A randomised controlled trial.

PubMed

Bataille, Aurélien; Guirimand, Avit; Szekely, Barbara; Michel-Cherqui, Mireille; Dumans, Virginie; Liu, Ngai; Chazot, Thierry; Fischler, Marc; Le Guen, Morgan

2017-11-27

Hypnosis has a positive effect on peri-operative anxiety and pain. The objective of this study was to assess the impact of a formal deep hypnosis session on the consumption of propofol for anaesthetic induction using automated administration of propofol guided by the bispectral index (BIS) in a closed loop. A 1 : 1 randomised, usual-care-controlled, single-centre trial. Tertiary care centre in France from April 2014 to December 2015. Female adult patients scheduled for outpatient gynaecological surgery under general anaesthesia. Before surgery, patients were randomised to receive either a deep hypnosis session or routine care. Anaesthetic induction was performed automatically by propofol without opioids and was assisted by the BIS in a closed loop. The primary endpoint was the propofol dose required for anaesthesia induction, defined as a BIS less than 60 for at least 30 s. Data for 31 patients in the hypnosis group and 35 in the control group were analysed. There was no evidence of a difference in the mean required propofol dose for anaesthetic induction between the hypnosis and the control groups (2.06 mg kg (95% confidence interval [1.68 to 2.43]) versus 1.79 mg kg (95% CI [1.54 to 2.03]), P = 0.25, respectively). The current study, which was designed to determine the effect of a deep hypnosis session on anaesthesia induction using an automated tool for propofol administration, failed to detect a difference in the required dose of propofol. ClinicalTrials.gov, NCT02249364.

Chamomile confers protection against hydrogen peroxide-induced toxicity through activation of Nrf2-mediated defense response.

PubMed

Bhaskaran, Natarajan; Srivastava, Janmejai K; Shukla, Sanjeev; Gupta, Sanjay

2013-01-01

Oxidative stress plays an important role in the development of various human diseases. Aqueous chamomile extract is used as herbal medicine, in the form of tea, demonstrated to possess antiinflammatory and antioxidant properties. We demonstrate the cytoprotective effects of chamomile on hydrogen peroxide (H₂O₂)-induced cellular damage in macrophage RAW 264.7 cells. Pretreatment of cells with chamomile markedly attenuated H₂O₂-induced cell viability loss in a dose-dependent manner. The mechanisms by which chamomile-protected macrophages from oxidative stress was through the induction of several antioxidant enzymes including NAD(P)H:quinone oxidoreductase, superoxide dismutase, and catalase and increase nuclear accumulation of the transcription factor Nrf2 and its binding to antioxidant response elements. Furthermore, chamomile dose-dependently reduced H₂O₂-mediated increase in the intracellular levels of reactive oxygen species. Our results, for the first time, demonstrate that chamomile has protective effects against oxidative stress and might be beneficial to provide defense against cellular damage. Copyright © 2012 John Wiley & Sons, Ltd.

Chamomile Confers Protection against Hydrogen Peroxide-Induced Toxicity through Activation of Nrf2-Mediated Defense Response

PubMed Central

Bhaskaran, Natarajan; Srivastava, Janmejai K.; Shukla, Sanjeev; Gupta, Sanjay

2014-01-01

Oxidative stress plays an important role in the development of various human diseases. Aqueous chamomile extract is used as herbal medicine, in the form of tea, demonstrated to possess antiinflammatory and antioxidant properties. We demonstrate the cytoprotective effects of chamomile on hydrogen peroxide (H2O2)-induced cellular damage in macrophage RAW 264.7 cells. Pretreatment of cells with chamomile markedly attenuated H2O2-induced cell viability loss in a dose-dependent manner. The mechanisms by which chamomile-protected macrophages from oxidative stress was through the induction of several antioxidant enzymes including NAD (P)H:quinone oxidoreductase, superoxide dismutase, and catalase and increase nuclear accumulation of the transcription factor Nrf2 and its binding to antioxidant response elements. Furthermore, chamomile dose-dependently reduced H2O2-mediated increase in the intracellular levels of reactive oxygen species. Our results, for the first time, demonstrate that chamomile has protective effects against oxidative stress and might be beneficial to provide defense against cellular damage. PMID:22511316

The effects of boric acid on sister chromatid exchanges and chromosome aberrations in cultured human lymphocytes.

PubMed

Arslan, Mehmet; Topaktas, Mehmet; Rencuzogullari, Eyyüp

2008-02-01

The aim of this study was to determine the possible genotoxic effects of boric acid (BA) (E284), which is used as an antimicrobial agent in food, by using sister chromatid exchange (SCEs) and chromosome aberration (CAs) tests in human peripheral lymphocytes. The human lymphocytes were treated with 400, 600, 800, and 1000 mug/mL concentrations of BA dissolved in dimethyl sulfoxide (DMSO), for 24 h and 48 h treatment periods. BA did not increase the SCEs for all the concentrations and treatment periods when compared to control and solvent control (DMSO). BA induced structural and total CAs at all the tested concentrations for 24 and 48 h treatment periods. The induction of the total CAs was dose dependent for the 24 h treatment period. However, BA did not cause numerical CAs. BA showed a cytotoxic effect by decreasing the replication index (RI) and mitotic index (MI). BA decreased the MI in a dose-dependent manner for the 24 h treatment period.

Combinatorial anticancer effects of curcumin and sorafenib towards thyroid cancer cells via PI3K/Akt and ERK pathways.

PubMed

Zhang, Junjia; Yu, Jichun; Xie, Rong; Chen, Wanzhi; Lv, Yunxia

2016-08-01

The objective of this study was to examine the in vitro combinatorial anticancer effects of curcumin and sorafenib towards thyroid cancer cells FTC133 using a MTT cytotoxicity assay, and to test whether the mechanism involves induction of apoptosis. The present results demonstrated that curcumin at 15-25 μM dose-dependently suppressed the proliferation of FTC133. Combined treatment (curcumin (25 μM) and sorafenib (2 μM)) resulted in a reduction in cell colony formation and significantly decreased the invasion and migration of FTC133 cells compared with that treated with individual drugs. Western blot showed that the levels of p-ERK and p-Akt proteins were significantly reduced (p < 0.01) in the medicine-treated FTC133 cells. The curcumin was found to dose-dependently inhibit the apoptosis of FTC133 cells possibly via PI3K/Akt and ERK pathways. There is a synergetic antitumour effect between curcumin and sorafenib.

[The effect of sodium phenylbutyrate to agents used in induction chemotherapy on laryngeal carcinoma cells Hep-2 in vitro].

PubMed

Gao, Jing; Ruan, Xinyong; Pan, Xinliang; Xu, Fenglei; Lei, Dapeng; Liu, Dayu

2005-08-01

To study the effect of sodium phenylbutyrate when it combined with agents used in induction chemotherapy on laryngeal carcinoma cells Hep-2 in vitro. MTT were used to examine the growth inhibition of Hep-2 cells treated by the combination of PB with 5-FU or CDDP in vitro. When 5-FU or CDDP combined with PB respectively, there was significantly difference between every two dose groups of the two agents or every dose group and control group ( P < 0.05). When the dosage of 5-FU or CDDP was definition,there was significantly difference between every two dose groups of PB ( P < 0.05). PB could enhance the cytotoxic effects of agents used in induction chemotherapy on laryngeal carcinoma cells Hep-2 in vitro, which showed the possibility in reinforcement the treatment effect and reduction the occurrence of the complication and toxic reaction of induction chemotherapy on laryngeal carcinoma.

Assessment of the risk of solar ultraviolet radiation to amphibians. I. Dose-dependent induction of hindlimb malformations in the northern leopard frog (Rana pipiens).

PubMed

Ankley, Gerald T; Diamond, Stephen A; Tietge, Joseph E; Holcombe, Gary W; Jensen, Kathleen M; Defoe, David L; Peterson, Ryan

2002-07-01

A number of environmental stressors have been hypothesized as responsible for recent increases in limb malformations in several species of North American amphibians. The purpose of this study was to generate dose-response data suitable for assessing the potential role of solar ultraviolet (UV) radiation in causing limb malformations in a species in which this phenomenon seemingly is particularly prevalent, the northern leopard frog (Rana pipiens). Frogs were exposed from early embryonic stages through complete metamorphosis to varying natural sunlight regimes, including unaltered (100%) sunlight, sunlight subjected to neutral density filtration to achieve relative intensities of 85%, 75%, 65%, 50%, and 25% of unaltered sunlight, and sunlight filtered with glass or acrylamide to attenuate, respectively, the UVB (290-320 nm) and UVB plus UVA (290-380 nm) portions of the spectrum. The experiments were conducted in a controlled setting, with continual monitoring of UVB, UVA, and visible light to support a robust exposure assessment. Full sunlight caused approximately 50% mortality of the frogs during early larval development; no significant treatment-related mortality occurred under any of the other exposure regimes, including 100% sunlight with glass or acrylamide filtration. There was a dose-dependent (p < 0.0001) induction of hindlimb malformations in the frogs, with the percentage of affected animals ranging from about 97% under unaltered sunlight to 0% in the 25% neutral density treatment. Malformations were comprised mostly of missing or truncated digits, and generally were bilateral as well as symmetrical. Filtration of sunlight with either glass or acrylamide both significantly reduced the incidence of malformed limbs. The estimated sunlight dose resulting in a 50% limb malformation rate (ED50) was 63.5%. The limb ED50 values based on measured sunlight intensities corresponded to average daily doses of 4.5 and 100 Wh x m(-2) for UVB and UVA, respectively. Exposure to sunlight also resulted in increased eye malformations in R. pipiens, however, the dose-response relationship for this endpoint was not monotonic. The results of this study, in conjunction with measured or predicted exposure data from natural settings, provide a basis for quantitative prediction of the risk of solar UV radiation to amphibians.

Protective effect of Tribulus terrestris fruit extract on cerulein-induced acute pancreatitis in mice

PubMed Central

Borran, Mina; Minaiyan, Mohsen; Zolfaghari, Behzad; Mahzouni, Parvin

2017-01-01

Objective: Antioxidant, anti-inflammatory, analgesic and antimicrobial activities of Tribulus terrestris (T. terrestris) could be helpful in the treatment of acute pancreatitis; thus, this study was designed to investigate the effects of T. terrestris on cerulein-induced acute pancreatitis in mice. Materials and Methods: Three doses (100, 200 and 400 mg/kg) of T. terrestris hydro-alcoholic extract were administered both orally (60 minutes before pancreatitis induction, p.o.) and intra-peritoneally (30 minutes before pancreatitis induction, i.p.) to different groups of mice (n=6). Pancreatitis was induced by five injections (i.p.) of cerulein 50μg/kg body weight with 1 hr intervals. Animals were euthanized 5 hr after the last injection of cerulein and tissue injures were assessed biochemically and pathologically. Results: T. terrestris extract 200 and 400mg/kg (p.o.) and T. terrestris extract 400 mg/kg (i.p.) reduced pancreatic tissue myeloperoxidase (MPO) activity and serum amylase and lipase levels and alleviated histological parameters. Conclusion: These data suggest that T. terrestris hydro-alcoholic extract was effective in protecting against experimental acute pancreatitis and possibly the efficacy depends on dose and route of administration. PMID:28748172

Analysis of a novel protocol of combined induction chemotherapy and concurrent chemoradiation in unresected non-small-cell lung cancer: a ten-year experience with vinblastine, Cisplatin, and radiation therapy.

PubMed

Waters, Eugenie; Dingle, Brian; Rodrigues, George; Vincent, Mark; Ash, Robert; Dar, Rashid; Inculet, Richard; Kocha, Walter; Malthaner, Richard; Sanatani, Michael; Stitt, Larry; Yaremko, Brian; Younus, Jawaid; Yu, Edward

2010-07-01

The London Regional Cancer Program (LRCP) uses a unique schedule of induction plus concurrent chemoradiation, termed VCRT (vinblastine, cisplatin, and radiation therapy), for the treatment of a subset of unresectable stage IIIA and IIIB non-small-cell lung cancer (NSCLC). This analysis was conducted to better understand the outcomes in VCRT-treated patients. We report a retrospective analysis of a large cohort of patients who underwent VCRT at the LRCP over a 10-year period, from 1996 to 2006. The analysis focused on OS, toxicities, and the outcomes from completion surgery in a small subset of patients. A total of 294 patients were included and 5-year OS, determined using Kaplan-Meier methodology, was 19.8% with a MST of 18.2 months. Reported grade 3-4 toxicities included neutropenia (39%), anemia (10%), pneumonitis (1%), and esophagitis (3%). Significant differences in survival between groups of patients were demonstrated with log-rank tests for completion surgery, use of radiation therapy, and cisplatin dose. Similarly, Univariate Cox regression showed that completion surgery, use of radiation therapy, cisplatin dose, and vinblastine dose were associated with increased survival. This retrospective analysis of a large cohort of patients reveals an OS for VCRT comparable to that reported in the literature for other current combined chemoradiation protocols. The success of this protocol seems to be dose dependent and the outcomes in those who underwent completion surgery suggests that pathologic complete remission is possible for IIIA and IIIB NSCLC.

Radiation-Induced Carcinogenesis: Mechanistically Based Differences between Gamma-Rays and Neutrons, and Interactions with DMBA

PubMed Central

Shuryak, Igor; Brenner, David J.; Ullrich, Robert L.

2011-01-01

Different types of ionizing radiation produce different dependences of cancer risk on radiation dose/dose rate. Sparsely ionizing radiation (e.g. γ-rays) generally produces linear or upwardly curving dose responses at low doses, and the risk decreases when the dose rate is reduced (direct dose rate effect). Densely ionizing radiation (e.g. neutrons) often produces downwardly curving dose responses, where the risk initially grows with dose, but eventually stabilizes or decreases. When the dose rate is reduced, the risk increases (inverse dose rate effect). These qualitative differences suggest qualitative differences in carcinogenesis mechanisms. We hypothesize that the dominant mechanism for induction of many solid cancers by sparsely ionizing radiation is initiation of stem cells to a pre-malignant state, but for densely ionizing radiation the dominant mechanism is radiation-bystander-effect mediated promotion of already pre-malignant cell clone growth. Here we present a mathematical model based on these assumptions and test it using data on the incidence of dysplastic growths and tumors in the mammary glands of mice exposed to high or low dose rates of γ-rays and neutrons, either with or without pre-treatment with the chemical carcinogen 7,12-dimethylbenz-alpha-anthracene (DMBA). The model provides a mechanistic and quantitative explanation which is consistent with the data and may provide useful insight into human carcinogenesis. PMID:22194850

Antitumor Activity and Induction of TP53-Dependent Apoptosis toward Ovarian Clear Cell Adenocarcinoma by the Dual PI3K/mTOR Inhibitor DS-7423

PubMed Central

Kashiyama, Tomoko; Oda, Katsutoshi; Ikeda, Yuji; Shiose, Yoshinobu; Hirota, Yasuhide; Inaba, Kanako; Makii, Chinami; Kurikawa, Reiko; Miyasaka, Aki; Koso, Takahiro; Fukuda, Tomohiko; Tanikawa, Michihiro; Shoji, Keiko; Sone, Kenbun; Arimoto, Takahide; Wada-Hiraike, Osamu; Kawana, Kei; Nakagawa, Shunsuke; Matsuda, Koichi; McCormick, Frank; Aburatani, Hiroyuki; Yano, Tetsu; Osuga, Yutaka; Fujii, Tomoyuki

2014-01-01

DS-7423, a novel, small-molecule dual inhibitor of phosphatidylinositol-3-kinase (PI3K) and mammalian target of rapamycin (mTOR), is currently in phase I clinical trials for solid tumors. Although DS-7423 potently inhibits PI3Kα (IC50 = 15.6 nM) and mTOR (IC50 = 34.9 nM), it also inhibits other isoforms of class I PI3K (IC50 values: PI3Kβ = 1,143 nM; PI3Kγ = 249 nM; PI3Kδ = 262 nM). The PI3K/mTOR pathway is frequently activated in ovarian clear cell adenocarcinomas (OCCA) through various mutations that activate PI3K-AKT signaling. Here, we describe the anti-tumor effect of DS-7423 on a panel of nine OCCA cell lines. IC50 values for DS-7423 were <75 nM in all the lines, regardless of the mutational status of PIK3CA. In mouse xenograft models, DS-7423 suppressed the tumor growth of OCCA in a dose-dependent manner. Flow cytometry analysis revealed a decrease in S-phase cell populations in all the cell lines and an increase in sub-G1 cell populations following treatment with DS-7423 in six of the nine OCCA cell lines tested. DS-7423-mediated apoptosis was induced more effectively in the six cell lines without TP53 mutations than in the three cell lines with TP53 mutations. Concomitantly with the decreased phosphorylation level of MDM2 (mouse double minute 2 homolog), the level of phosphorylation of TP53 at Ser46 was increased by DS-7423 in the six cell lines with wild-type TP53, with induction of genes that mediate TP53-dependent apoptosis, including p53AIP1 and PUMA at 39 nM or higher doses. Our data suggest that the dual PI3K/mTOR inhibitor DS-7423 may constitute a promising molecular targeted therapy for OCCA, and that its antitumor effect might be partly obtained by induction of TP53-dependent apoptosis in TP53 wild-type OCCAs. PMID:24504419

Cardiovascular and behavioral responses of gray wolves to ketamine-xylazine immobilization and antagonism by yohimbine

USGS Publications Warehouse

Kreeger, T.J.; Faggella, A.M.; Seal, U.S.; Mech, L.D.; Callahan, Margaret; Hall, B.

1987-01-01

Adult wolves (Canis lupus) were immobilized with 6.6 mg/kg ketamine hydrochloride (KET) and 2.2 mg/kg xylazine hydrochloride (XYL) administered intramuscularly. Induction time was 4.6 ± 0.3 min (x̄ ± SE). Immobilization resulted in significant bradycardia and hypertension (P < 0.05). Twenty min after induction, the wolves were given 0.05–0.60 mg/kg yohimbine hydrochloride (YOH). Yohimbine given intravenously produced dose-related increases in heart rate (HR) with doses >0.15 mg/kg resulting in extreme tachycardia (>300 bpm). All doses of YOH caused a temporary decrease in mean arterial blood pressure (MABP) with some individual animals manifesting profound hypotension (<30 torr) at doses >0.15 mg/kg. Increasing the dose of YOH above 0.15 mg/kg did not significantly decrease either arousal or ambulation times. Administering YOH at 40 or 60 min after induction resulted in decreased arousal and ambulation times. Stimulation by weighing and taking repeated blood samples during anesthesia did not shorten arousal times. We recommend that wolves immobilized with XYL-KET be antagonized with doses of YOH <0.15 mg/kg.

Pretreatment of low dose radiation reduces radiation-induced apoptosis in mouse lymphoma (EL4) cells.

PubMed

Kim, J H; Hyun, S J; Yoon, M Y; Ji, Y H; Cho, C K; Yoo, S Y

1997-06-01

Induction of an adaptive response to ionizing radiation in mouse lymphoma (EL4) cells was studied by using cell survival fraction and apoptotic nucleosomal DNA fragmentation as biological end points. Cells in early log phase were pre-exposed to low dose of gamma-rays (0.01 Gy) 4 or 20 hrs prior to high dose gamma-ray (4, 8 and 12 Gy for cell survival fraction analysis; 8 Gy for DNA fragmentation analysis) irradiation. Then cell survival fractions and the extent of DNA fragmentation were measured. Significant adaptive response, increase in cell survival fraction and decrease in the extent of DNA fragmentation were induced when low and high dose gamma-ray irradiation time interval was 4 hr. Addition of protein or RNA synthesis inhibitor, cycloheximide or 5,6-dichloro-1-beta-d-ribofuranosylbenzimidazole (DRFB), respectively during adaptation period, the period from low dose gamma-ray irradiation to high dose gamma-ray irradiation, was able to inhibit the induction of adaptive response, which is the reduction of the extent DNA fragmentation in irradiated EL4 cells. These data suggest that the induction of adaptive response to ionizing radiation in EL4 cells required both protein and RNA synthesis.

Ursodeoxycholic acid induces apoptosis of hepatocellular carcinoma cells in vitro.

PubMed

Zhu, Lei; Shan, Lu Juan; Liu, Yue Jian; Chen, Dan; Xiao, Xiao Guang; Li, Yan

2014-12-01

Ursodeoxycholic acid (UDCA) is widely used to treat chronic liver diseases, and its cytoprotective effect on normal hepatocytes has been shown. This study aimed to investigate the apoptotic effects of UDCA on hepatocellular carcinoma (HCC) cells and the underlying molecular events in vitro. HCC cells were treated by UDCA at different doses and periods of time to assess cell morphology, viability, apoptosis and gene expression using methyl thiazolyl tetrazolium (MTT), Annexin V/propidium iodide (PI) stain, transferase dUTP nick end labeling (TUNEL), enzyme-linked immunosorbent assay (ELISA), immunocytochemistry and quantitative reverse transcription polymerase chain reaction, respectively. UDCA treatment reduced cell viability but induced HCC cell apoptosis in dose-dependent and time-dependent manners. UDCA arrested HepG2 cells at phase S of the cell cycle. At the gene levels, UDCA downregulated Bcl-2 and second mitochondria-derived activator of caspase (Smac) protein expressions, but upregulated Bax and Livin proteins in HCC cells. At the highest concentration, UDCA inhibited Livin mRNA expression but increased Smac and caspase-3 mRNA expressions as well as the activity of caspase-3 in HCC cells. The induction of HCC cell apoptosis by UDCA was dose-dependent and time-dependent and was mediated by the regulation of Bax to Bcl-2 ratio, the expressions of Smac and Livin, and caspase-3 expression and activity. © 2014 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Comparison of the therapeutic dose of warfarin in HIV-infected and HIV-uninfected patients: a study of clinical practice.

PubMed

Jackson, B S; Mokoena, T

2017-02-08

People infected with HIV are prone to venous thrombosis. Treatment of thrombosis is primarily with warfarin. No studies have addressed the effects of HIV infection on warfarin dose. The aims of this study were to determine whether the therapeutic dose of warfarin and induction time to therapeutic dose in HIV-infected patients differ from that in HIV-uninfected patients. A prospective and retrospective descriptive study of induction time to therapeutic warfarin dose, as well as of ambulant therapeutic warfarin dose, was performed. HIV-infected and HIV-uninfected patients being treated after deep venous thrombosis with or without pulmonary embolism were compared. Sex and use of antiretroviral drugs (ARVs) were also compared in the groups. 234 patients were entered into the study. Induction time to therapeutic warfarin dose did not differ between the 2 groups. The mean therapeutic dose of warfarin was higher in the HIV-infected than the HIV-uninfected group: 6.06 vs 5.72 mg/day, but this was not statistically significant (p=0.29). There was no difference in therapeutic warfarin dose between ARV-naïve groups-HIV-uninfected and HIV-infected patients not on ARVs. There appears to be little effect of HIV infection on warfarin dosing. Warfarin therapy should be administered conventionally in HIV-infected patients. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Induction of Protective CTL Responses in Newborn Mice by a Murine Retrovirus

NASA Astrophysics Data System (ADS)

Sarzotti, Marcella; Robbins, Deanna S.; Hoffman, Paul M.

1996-03-01

The susceptibility of neonates to virus-induced disease is thought to reflect, in part, the immaturity of their immune systems. However, inoculation of newborn mice with low doses of Cas-Br-M murine leukemia virus induced a protective cytotoxic T lymphocyte (CTL) response. The inability of neonates to develop a CTL response to high doses of virus was not the result of immunological immaturity but correlated with the induction of a nonprotective type 2 cytokine response. Thus, the initial viral dose is critical in the development of protective immunity in newborns.

21 CFR 522.2005 - Propofol.

Code of Federal Regulations, 2011 CFR

2011-04-01

...—(i) As a single injection to provide general anesthesia for short procedures; for induction and maintenance of general anesthesia using incremental doses to effect; for induction of general anesthesia where maintenance is provided by inhalant anesthetics. (ii) For the induction and maintenance of anesthesia and for...

21 CFR 522.2005 - Propofol.

Code of Federal Regulations, 2014 CFR

2014-04-01

...—(i) As a single injection to provide general anesthesia for short procedures; for induction and maintenance of general anesthesia using incremental doses to effect; for induction of general anesthesia where maintenance is provided by inhalant anesthetics. (ii) For the induction and maintenance of anesthesia and for...

Non-thermal Plasma Induces Apoptosis in Melanoma Cells via Production of Intracellular Reactive Oxygen Species

PubMed Central

Sensenig, Rachel; Kalghatgi, Sameer; Cerchar, Ekaterina; Fridman, Gregory; Shereshevsky, Alexey; Torabi, Behzad; Arjunan, Krishna Priya; Podolsky, Erica; Fridman, Alexander; Friedman, Gary; Azizkhan-Clifford, Jane; Brooks, Ari D.

2012-01-01

Non-thermal atmospheric pressure dielectric barrier discharge (DBD) plasma may provide a novel approach to treat malignancies via induction of apoptosis. The purpose of this study was to evaluate the potential of DBD plasma to induce apoptosis in melanoma cells. Melanoma cells were exposed to plasma at doses that did not induce necrosis, and cell viability and apoptotic activity were evaluated by Trypan blue exclusion test, Annexin-V/PI staining, caspase-3 cleavage, and TUNEL® analysis. Trypan blue staining revealed that non-thermal plasma treatment significantly decreased the viability of cells in a dose-dependent manner 3 and 24 h after plasma treatment. Annexin-V/PI staining revealed a significant increase in apoptosis in plasma-treated cells at 24, 48, and 72 h post-treatment (p<0.001). Caspase-3 cleavage was observed 48 h post-plasma treatment at a dose of 15 J/cm2. TUNEL® analysis of plasma-treated cells demonstrated an increase in apoptosis at 48 and 72 h post-treatment (p<0.001) at a dose of 15 J/cm2. Pre-treatment with N-acetyl-L-cysteine (NAC), an intracellular reactive oxygen species (ROS) scavenger, significantly decreased apoptosis in plasma-treated cells at 5 and 15 J/cm2. Plasma treatment induces apoptosis in melanoma cells through a pathway that appears to be dependent on production of intracellular ROS. DBD plasma production of intracellular ROS leads to dose-dependent DNA damage in melanoma cells, detected by γ-H2AX, which was completely abrogated by pre-treating cells with ROS scavenger, NAC. Plasma-induced DNA damage in turn may lead to the observed plasma-induced apoptosis. Since plasma is non-thermal, it may be used to selectively treat malignancies. PMID:21046465

Intensified High-Dose Chemoradiotherapy With Induction Chemotherapy in Patients With Locally Advanced Non-Small-Cell Lung Cancer-Safety and Toxicity Results Within a Prospective Trial

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poettgen, Christoph, E-mail: christoph.poettgen@uk-essen.d; Eberhardt, Wilfried E.; Gauler, Thomas

2010-03-01

Purpose: To analyze the toxicity profile of an intensified definitive chemoradiotherapy (CRT) schedule in patients with locally advanced non-small-cell lung cancer (Stage IIIA N2/selected IIIB) treated within a prospective multicenter trial. Patients and Methods: After mediastinoscopy and routine staging procedures, three cycles of induction chemotherapy (cisplatin 50 mg/m{sup 2}, Days 1 and 8; paclitaxel 175 mg/m{sup 2} Day 1, every 21 days) were planned, followed by concurrent CRT (accelerated-hyperfractionated regimen, 45 Gy, 2 x 1.5 Gy/d, cisplatin 50 mg/m{sup 2}, Days 64 and 71, vinorelbine 20 mg/m{sup 2}, Days 64 and 71). At 45 Gy, a multidisciplinary panel decision wasmore » made regarding operability. Inoperable patients received definitive radiotherapy (total dose 65 or 71 Gy, depending on the mean lung dose) with additional concurrent chemotherapy (cisplatin 40 mg/m{sup 2}, Day 85; vinorelbine 15 mg/m{sup 2}, Days 85 and 92). Results: A total of 28 patients (23 men and 5 women; median age, 58 years; range 41-73; Stage IIIA in 3 and Stage IIIB in 25) were judged ineligible for surgery by the multidisciplinary panel and underwent definitive CRT (75% of the patients received 71 Gy). The maximum toxicity (Grade 3 or greater) during induction chemotherapy included leukopenia (11%) and anemia (4%). During concurrent CRT, leukopenia (Grade 3 or greater) was observed in 39% of the patients. The maximal nonhematologic toxicity during concurrent CRT included esophagitis (Grade 3 or greater) in 18% and pneumonitis (Grade 3 or greater) in 4% of the patients. At 3 years, the locoregional control rate was 52% (95% confidence interval, 29-75%) and the overall survival rate was 31% (95% confidence interval, 12-50%). Conclusion: This intensified treatment protocol with induction chemotherapy and concurrent CRT, including hyperfractionated-accelerated RT, showed only moderate toxicity and proved feasible. This treatment represents the definitive CRT arm of our ongoing multicenter randomized trial comparing definitive CRT and trimodality treatment.« less

Oxytocin prevents cartilage matrix destruction via regulating matrix metalloproteinases.

PubMed

Wu, Yixin; Wu, Tongyu; Xu, Binbin; Xu, Xiaoyan; Chen, Honggan; Li, Xiyao

2017-05-06

Degradation of the extracellular matrix type II Collagen (Col II) induced by proinflammatory cytokines such as tumor necrosis factor-α (TNF-α) is an important hallmark of Osteoarthritis (OA). Oxytocin (OT) is a well-known neurohypophysical hormone that is synthesized in the paraventricular (PVN) and supraoptic nuclei (SON) of the hypothalamus. In this study, we have found that oxytocin receptor (OTR) was expressed in human primary chondrocytes, and the expression of which was reduced in chondrocytes from OA patients and in response to TNF-α treatment in a dose dependent manner. Notably, it was shown that TNF-α -induced degradation of Col II was restored by treatment with OT in a dose-dependent manner. In addition, TNF-α treatment (10 ng/mL) highly elevated the expression of MMP-1 and MMP-13 in SW1353 chondrocytes, which were reversed by OT in a dose dependent manner at both gene and protein expression levels. In addition, it was demonstrated that the JAK2/STAT1 pathway was involved in the restoration effects of OT in the degradation of Col II. Lastly, knockdown of OTR abolished the inhibitory effects of OT on the degradation of col II and the induction of MMP-1 and MMP-13 expression, suggesting the involvement of OTR. Our study implied the therapeutic potential of OT for cartilage degradation. Copyright © 2017 Elsevier Inc. All rights reserved.

Oxymatrine inhibits the proliferation of prostate cancer cells in vitro and in vivo

PubMed Central

WU, CUNZAO; HUANG, WEIPING; GUO, YONG; XIA, PENG; SUN, XIANBIN; PAN, XIAODONG; HU, WEILIE

2015-01-01

Oxymatrine is an alkaloid, which is derived from the traditional Chinese herb, Sophora flavescens Aiton. Oxymatrine has been shown to exhibit anti-inflammatory, antiviral, and anticancer properties. The present study aimed to investigate the anticancer effects of oxymatrine in human prostate cancer cells, and the underlying molecular mechanisms of these effects. An MTT assay demonstrated that oxymatrine significantly inhibited the proliferation of prostate cancer cells in a time- and dose-dependent manner. In addition, flow cytometry and a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assay suggested that oxymatrine treatment may induce prostate cancer cell apoptosis in a dose-dependent manner. Furthermore, western blot analysis demonstrated a significant increase in the expression of p53 and bax, and a significant decrease in that of Bcl-2, in prostrate cancer cells in a dose-dependent manner. In vivo analysis demonstrated that oxymatrine inhibited tumor growth following subcutaneous inoculation of prostate cancer cells into nude mice. The results of the present study suggested that the antitumor properties of oxymatrine, may be associated with the inhibition of cell proliferation, and induction of apoptosis, via the regulation of apoptosis-associated gene expression. Therefore, the results may provide a novel approach for the development of prostate cancer therapy using oxymatrine, which is derived from the traditional Chinese herb, Sophora flavescens. PMID:25672672

Persistent induction of c-fos and c-jun expression by asbestos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heintz, N.H.; Mossman, B.T.; Janssen, Y.M.

To investigate the mechanisms of asbestos-induced carcinogenesis, expression of c-fos and c-jun protooncogenes was examined in rat pleural mesothelial cells and hamster tracheal epithelial cells after exposure to crocidolite or chrysotile asbestos. In contrast to phorbol 12-myristate 13-acetate, which induces rapid and transient increases in c-fos and c-jun mRNA, asbestos causes 2- to 5-fold increases in c-fos and c-jun mRNA that persist for at least 24 hr in mesothelial cells. The induction of c-fos and c-jun mRNA by asbestos in mesothelial cells is dose-dependent and is most pronounced with crocidolite, the type of asbestos most pathogenic in the causation ofmore » pleural mesothelioma. Induction of c-jun gene expression by asbestos occurs in tracheal epithelial cells but is not accompanied by a corresponding induction of c-fos gene expression. In both cell types, asbestos induces increases in protein factors that bind specifically to the DNA sites that mediate gene expression by the AP-1 family of transcription factors. The persistent induction of AP-1 transcription factors by asbestos suggests a model of asbestos-induced carcinogenesis involving chronic stimulation of cell proliferation through activation of the early response gene pathway that includes c-jun and/or c-fos. 30 refs., 5 figs.« less

In Vivo Visualization of Bacterial Colonization, Antigen Expression, and Specific T-Cell Induction following Oral Administration of Live Recombinant Salmonella enterica Serovar Typhimurium

PubMed Central

Bumann, Dirk

2001-01-01

Live attenuated Salmonella strains that express a foreign antigen are promising oral vaccine candidates. Numerous genetic modifications have been empirically tested, but their effects on immunogenicity are difficult to interpret since important in vivo properties of recombinant Salmonella strains such as antigen expression and localization are incompletely characterized and the crucial early inductive events of an immune response to the foreign antigen are not fully understood. Here, methods were developed to directly localize and quantitate the in situ expression of an ovalbumin model antigen in recombinant Salmonella enterica serovar Typhimurium using two-color flow cytometry and confocal microscopy. In parallel, the in vivo activation, blast formation, and division of ovalbumin-specific CD4+ T cells were followed using a well-characterized transgenic T-cell receptor mouse model. This combined approach revealed a biphasic induction of ovalbumin-specific T cells in the Peyer's patches that followed the local ovalbumin expression of orally administered recombinant Salmonella cells in a dose- and time-dependent manner. Interestingly, intact Salmonella cells and cognate T cells seemed to remain in separate tissue compartments throughout induction, suggesting a transport of killed Salmonella cells from the colonized subepithelial dome area to the interfollicular inductive sites. The findings of this study will help to rationally optimize recombinant Salmonella strains as efficacious live antigen carriers for oral vaccination. PMID:11402006

Sustained neuroprotection from a single intravitreal injection of PGJ₂ in a nonhuman primate model of nonarteritic anterior ischemic optic neuropathy.

PubMed

Miller, Neil R; Johnson, Mary A; Nolan, Theresa; Guo, Yan; Bernstein, Alexander M; Bernstein, Steven L

2014-10-08

Prostaglandin J₂ (PGJ₂) is neuroprotective in a murine model of nonarteritic anterior ischemic optic neuropathy (NAION). After assessing for potential toxicity, we evaluated the efficacy of a single intravitreal (IVT) injection of PGJ₂ in a nonhuman primate model of NAION (pNAION). We assessed PGJ₂ toxicity by administering it as a single high-dose intravenous (IV) injection, consecutive daily high-dose IV injections, or a single IVT injection in one eye of five adult rhesus monkeys. To assess efficacy, we induced pNAION in one eye of five adult male rhesus monkeys using a laser-activated rose bengal induction method. We then injected the eye with either PGJ₂ or phosphate-buffered saline (PBS) intravitreally immediately or 5 hours post induction. We performed a clinical assessment, optical coherence tomography, electrophysiological testing, fundus photography, and fluorescein angiography in all animals prior to induction and at 1 day, 1 week, 2 weeks, and 4 weeks after induction. Following analysis of the first eye, we induced pNAION in the contralateral eye and then injected either PGJ₂ or PBS. We euthanized all animals 5 weeks after final assessment of the fellow eye and performed both immunohistochemical and light and electron microscopic analyses of the retina and optic nerves. PGJ₂ caused no permanent systemic toxicity regardless of the amount injected or route of delivery, and there was no evidence of any ocular toxicity with the dose of PGJ₂ used in efficacy studies. Transient reduction in the amplitudes of the visual evoked potentials and the N95 component of the pattern electroretinogram (PERG) occurred after both IV and IVT administration of high doses of PGJ₂; however, the amplitudes returned to normal in all animals within 1 week. In all eyes, a single IVT dose of PGJ₂ administered immediately or shortly after induction of pNAION resulted in a significant reduction of clinical, electrophysiological, and histological damage compared with vehicle-injected eyes (P = 0.03 for both VEP and PERG; P = 0.05 for axon counts). In nonhuman primates, PGJ₂ administered either intravenously or intravitreally produces no permanent toxicity at even four times the dose given for neuroprotection. Additionally, a single IVT dose of PGJ₂ is neuroprotective when administered up to 5 hours after induction of pNAION. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Critical target and dose and dose-rate responses for the induction of chromosomal instability by ionizing radiation

NASA Technical Reports Server (NTRS)

Limoli, C. L.; Corcoran, J. J.; Milligan, J. R.; Ward, J. F.; Morgan, W. F.

1999-01-01

To investigate the critical target, dose response and dose-rate response for the induction of chromosomal instability by ionizing radiation, bromodeoxyuridine (BrdU)-substituted and unsubstituted GM10115 cells were exposed to a range of doses (0.1-10 Gy) and different dose rates (0.092-17.45 Gy min(-1)). The status of chromosomal stability was determined by fluorescence in situ hybridization approximately 20 generations after irradiation in clonal populations derived from single progenitor cells surviving acute exposure. Overall, nearly 700 individual clones representing over 140,000 metaphases were analyzed. In cells unsubstituted with BrdU, a dose response was found, where the probability of observing delayed chromosomal instability in any given clone was 3% per gray of X rays. For cells substituted with 25-66% BrdU, however, a dose response was observed only at low doses (<1.0 Gy); at higher doses (>1.0 Gy), the incidence of chromosomal instability leveled off. There was an increase in the frequency and complexity of chromosomal instability per unit dose compared to cells unsubstituted with BrdU. The frequency of chromosomal instability appeared to saturate around approximately 30%, an effect which occurred at much lower doses in the presence of BrdU. Changing the gamma-ray dose rate by a factor of 190 (0.092 to 17.45 Gy min(-1)) produced no significant differences in the frequency of chromosomal instability. The enhancement of chromosomal instability promoted by the presence of the BrdU argues that DNA comprises at least one of the critical targets important for the induction of this end point of genomic instability.

Comparative molecular field analysis to derive pharmacophore maps for induction doses of intravenous anaesthetic agents.

PubMed

Sear, J W

2011-03-01

The present study examines the molecular basis of induction of anaesthesia by i.v. hypnotic agents using comparative molecular field analysis (CoMFA). ED(50) induction doses for 14 i.v. anaesthetics in human subjects (expressed as molar dose per kilogram body weight) were obtained from the literature. Immobilizing potency data for the same 14 agents (expressed as the EC(50) plasma free drug concentrations that abolish movement in response to a noxious stimulus in 50% patients) were taken from our previous publication. These data were used to form CoMFA models for the two aspects of anaesthetic activity. Molecular alignment was achieved by field-fit minimization techniques. The lead structure for both models was eltanolone. The final CoMFA model for the ED(50) induction dose was based on two latent variables, and explained 99.3% of the variance in observed activities. It showed good intrinsic predictability (cross-validated q(2)=0.849). The equivalent model for immobilizing activity was also based on two latent variables, with r(2)=0.988 and q(2)=0.852. Although there was a correlation between -log ED(50) and -log EC(50) (r(2)=0.779), comparison of the pharmacophore maps showed poor correlation for both electrostatic and steric regions when isocontours were constructed by linking lattice grid points, making the greatest 40% contributions; the relative contributions of electrostatic and steric interactions differing between the models (induction dose: 2.5:1; immobilizing activity 1.8:1). Comparison of two CoMFA activity models shows only small elements of commonality, suggesting that different molecular features may be responsible for these two properties of i.v. anaesthetics.

Pharmacokinetics and anesthetic and cardiopulmonary effects of propofol in red-tailed hawks (Buteo jamaicensis) and great horned owls (Bubo virginianus).

PubMed

Hawkins, Michelle G; Wright, Bonnie D; Pascoe, Peter J; Kass, Philip H; Maxwell, Lara K; Tell, Lisa A

2003-06-01

To determine induction doses, anesthetic constant rate infusions (CRI), and cardiopulmonary effects of propofol in red-tailed hawks and great horned owls and propofol pharmacokinetics in the owls during CRI. 6 red-tailed hawks and 6 great horned owls. The CRI dose necessary for a loss of withdrawal reflex was determined via specific stimuli. Anesthesia was induced by IV administration of propofol (1 mg/kg/min) and maintained by CRI at the predetermined dose for 30 minutes. Heart and respiratory rates, arterial blood pressures, and blood gas tensions were obtained in awake birds and at various times after induction. End-tidal CO2 (ETCO2) concentration and esophageal temperature were obtained after induction. Propofol plasma concentrations were obtained after induction and after completion of the CRI in the owls. Recovery times were recorded. Mean +/- SD doses for induction and CRI were 4.48 +/- 1.09 mg/kg and 0.48 +/- 0.06 mg/kg/min, respectively, for hawks and 3.36 +/- 0.71 mg/kg and 0.56 +/- 0.15 mg/kg/min, respectively, for owls. Significant increases in PaCO2, HCO3, and ETCO2 in hawks and owls and significant decreases in arterial pH in hawks were detected. A 2-compartment model best described the owl pharmacodynamic data. Recovery times after infusion were prolonged and varied widely. Central nervous system excitatory signs were observed during recovery. Effects on blood pressure were minimal, but effective ventilation was reduced, suggesting the need for careful monitoring during anesthesia. Prolonged recovery periods with moderate-to-severe excitatory CNS signs may occur in these species at these doses.

A review: Development of a microdose model for analysis of adaptive response and bystander dose response behavior.

PubMed

Leonard, Bobby E

2008-02-27

Prior work has provided incremental phases to a microdosimetry modeling program to describe the dose response behavior of the radio-protective adaptive response effect. We have here consolidated these prior works (Leonard 2000, 2005, 2007a, 2007b, 2007c) to provide a composite, comprehensive Microdose Model that is also herein modified to include the bystander effect. The nomenclature for the model is also standardized for the benefit of the experimental cellular radio-biologist. It extends the prior work to explicitly encompass separately the analysis of experimental data that is 1.) only dose dependent and reflecting only adaptive response radio-protection, 2.) both dose and dose-rate dependent data and reflecting only adaptive response radio-protection for spontaneous and challenge dose damage, 3.) only dose dependent data and reflecting both bystander deleterious damage and adaptive response radio-protection (AR-BE model). The Appendix cites the various applications of the model. Here we have used the Microdose Model to analyze the, much more human risk significant, Elmore et al (2006) data for the dose and dose rate influence on the adaptive response radio-protective behavior of HeLa x Skin cells for naturally occurring, spontaneous chromosome damage from a Brachytherapy type (125)I photon radiation source. We have also applied the AR-BE Microdose Model to the Chromosome inversion data of Hooker et al (2004) reflecting both low LET bystander and adaptive response effects. The micro-beam facility data of Miller et al (1999), Nagasawa and Little (1999) and Zhou et al (2003) is also examined. For the Zhou et al (2003) data, we use the AR-BE model to estimate the threshold for adaptive response reduction of the bystander effect. The mammogram and diagnostic X-ray induction of AR and protective BE are observed. We show that bystander damage is reduced in the similar manner as spontaneous and challenge dose damage as shown by the Azzam et al (1996) data. We cite primary unresolved questions regarding adaptive response behavior and bystander behavior. The five features of major significance provided by the Microdose Model so far are 1. Single Specific Energy Hits initiate Adaptive Response. 2. Mammogram and diagnostic X-rays induce a protective Bystander Effect as well as Adaptive Response radio-protection. 3. For mammogram X-rays the Adaptive Response protection is retained at high primer dose levels. 4. The dose range of the AR protection depends on the value of the Specific Energy per Hit, 1 >. 5. Alpha particle induced deleterious Bystander damage is modulated by low LET radiation.

Antibodies to biotinylated red blood cells in adults and infants: improved detection, partial characterization, and dependence on red blood cell-biotin dose.

PubMed

Schmidt, Robert L; Mock, Donald M; Franco, Robert S; Cohen, Robert M; North, Anne K; Cancelas, José A; Geisen, Christof; Strauss, Ronald G; Vlaar, Alexander P; Nalbant, Demet; Widness, John A

2017-06-01

Biotin-labeled red blood cells (BioRBCs) are used for in vivo kinetic studies. Because BioRBC dosing occasionally induces antibodies, a sensitive and specific anti-BioRBC detection assay is needed. Aims were to 1) develop a gel card assay to evaluate existing, naturally occurring and BioRBC-induced plasma antibodies, 2) compare gel card and tube agglutination detection results, and 3) test for a relationship of antibody induction and BioRBC dose. Reagent BioRBCs were prepared using sulfo-NHS biotin ranging from densities 18 (BioRBC-18) to 1458 (BioRBC-1458) µg/mL RBCs. Among BioRBC-exposed subjects, gel card and tube agglutination results were concordant in 21 of 22 adults and all 19 infant plasma samples. Gel card antibody detection sensitivity was more than 10-fold greater than tube agglutination. Twelve to 16 weeks after BioRBC exposure, induced anti-antibodies were detected by gel card in three of 26 adults (12%) at reagent densities BioRBC-256 or less, but in none of 41 infants. Importantly, induced anti-BioRBC antibodies were associated with higher BioRBC dose (p = 0.008); no antibodies were detected in 18 subjects who received BioRBC doses less than or equal to BioRBC-18. For noninduced BioRBC antibodies, six of 1125 naïve adults (0.3%) and none of 46 naïve infants demonstrated existing anti-BioRBC antibodies using reagent BioRBC-140 or -162. Existing anti-BioRBCs were all neutralized by biotin compounds, while induced antibodies were not. The gel card assay is more sensitive than the tube agglutination assay. We recommend reagent BioRBC-256 for identifying anti-BioRBCs. Use of a low total RBC biotin label dose (≤ BioRBC-18) may minimize antibody induction. © 2017 AABB.

[Induction of glutathione and activation of immune functions by low-dose, whole-body irradiation with gamma-rays].

PubMed

Kojima, Shuji

2006-10-01

We first examined the relation between the induction of glutathione and immune functions in mice after low-dose gamma-ray irradiation. Thereafter, inhibition of tumor growth by radiation was confirmed in Ehrlich solid tumor (EST)-bearing mice. The total glutathione level of the splenocytes transiently increased soon after irradiation and reached a maximum at around 4 h postirradiation. Thereafter, the level reverted to the 0 h value by 24 h postirradiation. A significantly high splenocyte proliferative response was also recognized 4 h postirradiation. Natural killer (NK) activity was also increased significantly in a similar manner. The time at which the response reached the maximum coincided well with that of maximum total glutathione levels of the splenocytes in the gamma-ray-irradiated mice. Reduced glutathione exogenously added to splenocytes obtained from normal mice enhanced the proliferative response and NK activity in a dose-dependent manner. The inhibitory effects of radiation on tumor growth was then examined in EST-bearing mice. Repeated low-dose irradiation (0.5 Gy, four times, before and within an early time after inoculation) significantly delayed the tumor growth. Finally, the effect of single low-dose (0.5 Gy), whole-body gamma-ray irradiation on immune balance was examined to elucidate the mechanism underlying the antitumor immunity. The percentage of B cells in blood lymphocytes was selectively decreased after radiation, concomitant with an increase in that of the helper T cell population. The IFN-gamma level in splenocyte culture prepared from EST-bearing mice was significantly increased 48 h after radiation, although the level of IL-4 was unchanged. IL-12 secretion from macrophages was also enhanced by radiation. These results suggest that low-dose gamma-rays induce Th1 polarization and enhance the activities of tumoricidal effector cells, leading to an inhibition of tumor growth.

Long-term results of children with acute myeloid leukemia: a report of three consecutive Phase III trials by the Children's Cancer Group: CCG 251, CCG 213 and CCG 2891.

PubMed

Smith, F O; Alonzo, T A; Gerbing, R B; Woods, W G; Arceci, R J

2005-12-01

The Children's Cancer Group (CCG) conducted three Phase III prospective clinical trials for children with de novo acute myeloid leukemia between the years 1979 and 1995. A total of 1903 eligible children ages birth to 21 years of age were enrolled on CCG 251 (n=485), CCG 213 (n=532) and CCG 2891 (n=886). Follow-up is ongoing, with medians of 7.9, 10.9 and 8.6 years, respectively. These three clinical trials developed dose- and time-intensive induction regimens based upon high-dose cytarabine and daunomycin and randomly assigned patients to allogeneic bone marrow transplantation in first remission if an HLA-matched related donor was identified. Despite dose- and time-intensive induction regimens, remission induction rates remained relatively stable at 77-78%. However, overall survival, event-free survival and disease-free survival (DFS) increased for patients receiving intensive-timing induction therapy in comparison to patients who received standard-timing induction, regardless of the type of postremission therapy. Outcomes were best for patients receiving intensive-timing induction followed by matched related donor allogeneic transplantation with DFS of 65+/-9% at 6 years. These three clinical trials have established a strong foundation for the development of future studies focusing on further risk group stratification and the development of novel, molecularly-targeted therapies.

Oncological outcomes of metastatic testicular cancers under centralized management through regional medical network.

PubMed

Inai, Hiromu; Kawai, Koji; Kojima, Takahiro; Joraku, Akira; Shimazui, Toru; Yamauchi, Atsushi; Miyagawa, Tomoaki; Endo, Tsuyoshi; Fukuhara, Yoshiharu; Miyazaki, Jun; Uchida, Katsunori; Nishiyama, Hiroyuki

2013-12-01

To investigate the dose intensity of induction chemotherapy and oncological outcomes of metastatic testicular cancer under centralized management through a regional medical network. We retrospectively analyzed the outcomes of 86 metastatic testicular cancer patients who were given induction chemotherapy at Tsukuba University Hospital and four branch hospitals between January 2000 and November 2010. Principally, management of patients with poor-prognosis disease and patients having risk factors for bleomycin, etoposide and cisplatin were referred to Tsukuba University Hospital before chemotherapy. For high-risk groups, etoposide and cisplatin or etoposide, ifosfamide and cisplatin was used as an alternative to bleomycin, etoposide and cisplatin. Overall, 56 and 30 patients were treated at Tsukuba University Hospital and branch hospitals, respectively. Forty-seven, 18 and 21 patients were classified with good-, intermediate- and poor-prognosis disease, respectively, according to the International Germ Cell Cancer Collaborative Group criteria. Eighteen of the 21 patients (86%) with poor-prognosis disease were treated at Tsukuba University Hospital from the beginning of induction chemotherapy. Induction chemotherapy with a high relative dose intensity was possible in most patients. The average relative dose intensity of each drug was >0.96. Treatment procedures other than induction chemotherapy were efficiently centralized; 74% of post-chemotherapy surgery and all second-line or subsequent chemotherapies were performed at Tsukuba University Hospital. The 5-year overall survival rates of the good-, intermediate- and poor-prognosis groups were 97, 93 and 84%, respectively. Induction chemotherapy with high relative dose intensity, post-chemotherapy surgery and salvage chemotherapy was accomplished efficiently through centralization of management. Oncological outcomes were excellent, especially in patients with poor-prognosis disease, whose 5-year OS reached 84%.

Factors impacting short and long-term kidney graft survival: modification by single intra-operative -high-dose induction with ATG-Fresenius.

PubMed

Kaden, Jürgen; May, Gottfried; Völp, Andreas; Wesslau, Claus

2011-01-01

A majority of recipients benefited from the intra-operative single high-dose induction (HDI) with ATG-Fresenius (ATG-F) still leaving a group of recipients who did not profit from this kind of induction. Therefore the aim of this retrospective analysis was 1st to identify the risk factors impacting short and long-term graft survival, and 2nd to assess the efficacy of this type of induction in kidney graft recipients with or without these risk factors. A total of 606 recipients receiving two different immunosuppressive treatment regimens (1st: Triple drug therapy [TDT, n=196] consisting mainly of steroids, azathioprine and cyclosporine; 2nd: TDT + 9 mg/kg ATG-F intra-operatively [HDI, n=410]) were included in this analysis and grouped according to their kidney graft survival time (short GST: ≤1 yr, n=100 and long GST: >5 yrs, n=506). The main risk factors associated with a shortened graft survival were pre-transplant sensitization, re-transplantation, rejections (in particular vascular or mixed ones) and the necessity of a long-term anti-rejection therapy. Adding ATG-F single high dose induction to TDT was more efficient in prolonging kidney graft survival than TDT alone not only in recipients without any risk factors (p<0.005) but also in recipients with at least one risk factor (p<0.021). Only in 4.6% of recipients having two or more risk factors this effect could not be demonstrated. The intra-operative single high-dose induction with ATG-F significantly improves the kidney graft survival in recipients with or without risk factors and can therefore be recommended.

Comparison of the potency of different propofol formulations: a randomized, double-blind trial using closed-loop administration.

PubMed

Le Guen, Morgan; Grassin-Delyle, Stanislas; Cornet, Camille; Genty, Antoine; Chazot, Thierry; Dardelle, Dominique; Liu, Ngai; Dreyfus, Jean-François; Mazoit, Jean-Xavier; Devillier, Philippe; Alvarez, Jean-Claude; Sessler, Daniel I; Fischler, Marc

2014-02-01

Several commercial formulations of propofol are available. The primary outcome of this study was the required dose of propofol alone or combined with lidocaine to achieve induction of general anesthesia. This multicenter, double-blinded trial randomized patients (American Society of Anesthesiologists physical status I-III) just before elective surgery with the use of a computer-generated list. Three different propofol 1% formulations-Diprivan (Astra-Zeneca, Cheshire, United Kingdom), Propoven (Fresenius-Kabi AG, Bad Homburg, Germany), and Lipuro (B-Braun, Melshungen AG, Germany)-were compared with either placebo (saline solution) or lidocaine 1% mixed to the propofol solution. Depth of anesthesia was automatically guided by bispectral index and by a computerized closed-loop system for induction, thus avoiding dosing bias. The authors recorded the total dose of propofol and duration of induction and the patient's discomfort through a behavioral scale (facial expression, verbal response, and arm withdrawal) ranging from 0 to 6. The authors further evaluated postoperative recall of pain using a Visual Analog Scale. Of the 227 patients enrolled, 217 were available for analysis. Demographic characteristics were similar in each group. Propoven required a higher dose for induction (2.2 ± 0.1 mg/kg) than Diprivan (1.8 ± 0.1 mg/kg) or Lipuro (1.7 ± 0.1 mg/kg; P = 0.02). However, induction doses were similar when propofol formulations were mixed with lidocaine. Patient discomfort during injection was significantly reduced with lidocaine for every formulation: Diprivan (0.5 ± 0.3 vs. 2.3 ± 0.3), Propoven (0.4 ± 0.3 vs. 2.4 ± 0.3), and Lipuro (1.1 ± 0.3 vs. 1.4 ± 0.3), all differences significant, with P < 0.0001. No adverse effect was reported. Plain propofol formulations are not equipotent, but comparable doses were required when lidocaine was concomitantly administered.

Lactose in Human Breast Milk an Inducer of Innate Immunity with Implications for a Role in Intestinal Homeostasis

PubMed Central

Printz, Gordana; Yoshio, Hiroyuki; Alvelius, Gunvor; Lagercrantz, Hugo; Strömberg, Roger; Jörnvall, Hans; Gudmundsson, Gudmundur H.; Agerberth, Birgitta

2013-01-01

Postpartum, infants have not yet established a fully functional adaptive immune system and are at risk of acquiring infections. Hence, newborns are dependent on the innate immune system with its antimicrobial peptides (AMPs) and proteins expressed at epithelial surfaces. Several factors in breast milk are known to confer immune protection, but which the decisive factors are and through which manner they work is unknown. Here, we isolated an AMP-inducing factor from human milk and identified it by electrospray mass spectrometry and NMR to be lactose. It induces the gene (CAMP) that encodes the only human cathelicidin LL-37 in colonic epithelial cells in a dose- and time-dependent manner. The induction was suppressed by two different p38 antagonists, indicating an effect via the p38-dependent pathway. Lactose also induced CAMP in the colonic epithelial cell line T84 and in THP-1 monocytes and macrophages. It further exhibited a synergistic effect with butyrate and phenylbutyrate on CAMP induction. Together, these results suggest an additional function of lactose in innate immunity by upregulating gastrointestinal AMPs that may lead to protection of the neonatal gut against pathogens and regulation of the microbiota of the infant. PMID:23326523

Quantitative patterns between plant volatile emissions induced by biotic stresses and the degree of damage

PubMed Central

Niinemets, Ülo; Kännaste, Astrid; Copolovici, Lucian

2013-01-01

Plants have to cope with a plethora of biotic stresses such as herbivory and pathogen attacks throughout their life cycle. The biotic stresses typically trigger rapid emissions of volatile products of lipoxygenase (LOX) pathway (LOX products: various C6 aldehydes, alcohols, and derivatives, also called green leaf volatiles) associated with oxidative burst. Further a variety of defense pathways is activated, leading to induction of synthesis and emission of a complex blend of volatiles, often including methyl salicylate, indole, mono-, homo-, and sesquiterpenes. The airborne volatiles are involved in systemic responses leading to elicitation of emissions from non-damaged plant parts. For several abiotic stresses, it has been demonstrated that volatile emissions are quantitatively related to the stress dose. The biotic impacts under natural conditions vary in severity from mild to severe, but it is unclear whether volatile emissions also scale with the severity of biotic stresses in a dose-dependent manner. Furthermore, biotic impacts are typically recurrent, but it is poorly understood how direct stress-triggered and systemic emission responses are silenced during periods intervening sequential stress events. Here we review the information on induced emissions elicited in response to biotic attacks, and argue that biotic stress severity vs. emission rate relationships should follow principally the same dose–response relationships as previously demonstrated for different abiotic stresses. Analysis of several case studies investigating the elicitation of emissions in response to chewing herbivores, aphids, rust fungi, powdery mildew, and Botrytis, suggests that induced emissions do respond to stress severity in dose-dependent manner. Bi-phasic emission kinetics of several induced volatiles have been demonstrated in these experiments, suggesting that next to immediate stress-triggered emissions, biotic stress elicited emissions typically have a secondary induction response, possibly reflecting a systemic response. The dose–response relationships can also vary in dependence on plant genotype, herbivore feeding behavior, and plant pre-stress physiological status. Overall, the evidence suggests that there are quantitative relationships between the biotic stress severity and induced volatile emissions. These relationships constitute an encouraging platform to develop quantitative plant stress response models. PMID:23888161

Comparative Study of Oral and Vaginal Misoprostol for Induction of Labour, Maternal and Foetal Outcome

PubMed Central

Komala, Kambhampati; Reddy, Meherlatha; Quadri, Iqbal Jehan; B., Suneetha; V., Ramya

2013-01-01

Background: Misoprostol is a new promising agent for cervical ripening and induction of labour .The ideal dose, route and frequency of administration of misoprostol are still under investigation. Although, vaginal application of misoprostol has been validated as a reasonable mean of induction, there is a patient resistance to digital examination and there is a risk of ascending infection. For this reason, oral administration of misoprostol for cervical ripening and labour induction has been tried. Aims and Objectives: To compare 50μg of oral misoprostol versus 25μg of intravaginal misoprostol for induction of labour at term and maternal, foetal outcomes. Methods: Two hundred women who were at term, with indication for induction of labour and Bishop scores of ≤5 were randomly assigned to receive misoprostol 50μg or 25μg intravaginal, every 4-6 hours, for a maximum of 5 doses. In either group, pregnant females with inadequate uterine contractions despite being given maximum 5 doses of misoprostol, were augmented using oxytocin. The primary outcome measure was time-interval from induction to vaginal delivery and vaginal delivery rate within 24 hours. Results: The median induction to vaginal delivery time in oral group (12.92h) and vaginal group (14.04 h) was not significant. Oral misoprostol resulted in more number of vaginal deliveries as compared to vaginal misoprostol (94% as compared to 86%), which was not significant. There was a significantly higher incidence of uterine tachysystole in the vaginal group, as compared to oral group. There were no significant differences between the groups with respect to oxytocin augmentation, caesarean section rate, analgesic requirement and neonatal outcome. Conclusion: Oral misoprostol is as efficacious as vaginal misoprostol because of shorter induction delivery interval, lower caesarean section rates, and lower incidence of failed induction rates. Lower incidence of foetal distress and easy intake are observed if the drug is administered orally. PMID:24551660

Oncogenic RAS Enables DNA Damage- and p53-Dependent Differentiation of Acute Myeloid Leukemia Cells in Response to Chemotherapy

PubMed Central

Meyer, Mona; Rübsamen, Daniela; Slany, Robert; Illmer, Thomas; Stabla, Kathleen; Roth, Petra; Stiewe, Thorsten

2009-01-01

Acute myeloid leukemia (AML) is a clonal disease originating from myeloid progenitor cells with a heterogeneous genetic background. High-dose cytarabine is used as the standard consolidation chemotherapy. Oncogenic RAS mutations are frequently observed in AML, and are associated with beneficial response to cytarabine. Why AML-patients with oncogenic RAS benefit most from high-dose cytarabine post-remission therapy is not well understood. Here we used bone marrow cells expressing a conditional MLL-ENL-ER oncogene to investigate the interaction of oncogenic RAS and chemotherapeutic agents. We show that oncogenic RAS synergizes with cytotoxic agents such as cytarabine in activation of DNA damage checkpoints, resulting in a p53-dependent genetic program that reduces clonogenicity and increases myeloid differentiation. Our data can explain the beneficial effects observed for AML patients with oncogenic RAS treated with higher dosages of cytarabine and suggest that induction of p53-dependent differentiation, e.g. by interfering with Mdm2-mediated degradation, may be a rational approach to increase cure rate in response to chemotherapy. The data also support the notion that the therapeutic success of cytotoxic drugs may depend on their ability to promote the differentiation of tumor-initiating cells. PMID:19890398

Bioactive compounds from crocodile (Crocodylus siamensis) white blood cells induced apoptotic cell death in hela cells.

PubMed

Patathananone, Supawadee; Thammasirirak, Sompong; Daduang, Jureerut; Chung, Jing Gung; Temsiripong, Yosapong; Daduang, Sakda

2016-08-01

Crocodile (Crocodylus siamensis) white blood cell extracts (WBCex) were examined for anticancer activity in HeLa cell lines using the MTT assay. The percentage viability of HeLa cells significantly deceased after treatment with WBCex in a dose- and time-dependent manner. The IC50 dose was suggested to be approximately 225 μg/mL protein. Apoptotic cell death occurred in a time-dependent manner based on investigation by flow cytometry using annexin V-FITC and PI staining. DAPI nucleic acid staining indicated increased chromatin condensation. Caspase-3, -8 and -9 activities also increased, suggesting the induction of the caspase-dependent apoptotic pathway. Furthermore, the mitochondrial membrane potential (ΔΨm ) of HeLa cells was lost as a result of increasing levels of Bax and reduced levels of Bcl-2, Bcl-XL, Bcl-Xs, and XIAP. The decreased ΔΨm led to the release of cytochrome c and the activation of caspase-9 and -3. Apoptosis-inducing factor translocated into the nuclei, and endonuclease G (Endo G) was released from the mitochondria. These results suggest that anticancer agents in WBCex can induce apoptosis in HeLa cells via both caspase-dependent and -independent pathways. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 986-997, 2016. © 2015 Wiley Periodicals, Inc.

Induction of Metallothionein Expression After Exposure to Conventional Cigarette Smoke but Not Electronic Cigarette (ECIG)-Generated Aerosol in Caenorhabditis elegans

PubMed Central

Cobb, Eric; Hall, Julie; Palazzolo, Dominic L.

2018-01-01

Aim: With the invention of electronic cigarettes (ECIG), many questions have been raised regarding their safety as an alternative to smoking conventional cigarettes. Conventional cigarette smoke contains a variety of toxicants including heavy metals. However, ECIG-generated aerosol contains only trace amounts of metals, adding to the argument for it being a safer alternative. In response to heavy metal exposure, metallothioneins are induced in cells to help store the metal, detoxify the body, and are also known responders to oxidative stress. In an attempt to add to the evaluation of the safety of ECIGs, metallothionein expression was quantified using the nematode Caenorhabditis elegans as an assessment of stress induced cellular damage caused by exposure. Methods: Adult nematodes were exposed to either ECIG aerosol or conventional cigarette smoke at doses of 15, 30, and 45 puffs, the equivalent of one, two, and three cigarettes, respectively. Movement, survival, and stress-induced sleep were assessed for up to 24 h after exposure. Relative expression levels for mtl-1 and mtl-2, C. elegans metallothionein genes, were analyzed after 1, 5, and 24 h post exposure using quantitative RT-PCR. Results: Nematodes exposed to conventional cigarette smoke underwent stress-induced sleep in a dose dependent manner with animals recovering to values within the range of air control after 5 h post exposure. Those exposed to ECIG aerosol did not undergo stress-induced sleep and were indistinguishable from controls. The expression of mtl-1 increased in a dose and time dependent manner in C. elegans exposed to conventional cigarette smoke, with a maximum expression observed at 5 h post exposure of 45 puffs. No induction of mtl-2 was observed in any animals. Additionally, ECIG aerosol did not induce expression of mtl-1 and mtl-2 at levels different than those of untreated. Conclusion: ECIG aerosol failed to induce a stress response in C. elegans. In contrast, conventional cigarette smoke induced the production of mtl-1 in a manner that correlates with the induction of stress-induced sleep suggesting a stress response to damage. The lack of cellular stress response to ECIG aerosol suggests it may be a safer alternative to conventional cigarettes. PMID:29740339

Folate regulation of axonal regeneration in the rodent central nervous system through DNA methylation.

PubMed

Iskandar, Bermans J; Rizk, Elias; Meier, Brenton; Hariharan, Nithya; Bottiglieri, Teodoro; Finnell, Richard H; Jarrard, David F; Banerjee, Ruma V; Skene, J H Pate; Nelson, Aaron; Patel, Nirav; Gherasim, Carmen; Simon, Kathleen; Cook, Thomas D; Hogan, Kirk J

2010-05-01

The folate pathway plays a crucial role in the regeneration and repair of the adult CNS after injury. Here, we have shown in rodents that such repair occurs at least in part through DNA methylation. In animals with combined spinal cord and sciatic nerve injury, folate-mediated CNS axon regeneration was found to depend on injury-related induction of the high-affinity folate receptor 1 (Folr1). The activity of folate was dependent on its activation by the enzyme dihydrofolate reductase (Dhfr) and a functional methylation cycle. The effect of folate on the regeneration of afferent spinal neurons was biphasic and dose dependent and correlated closely over its dose range with global and gene-specific DNA methylation and with expression of both the folate receptor Folr1 and the de novo DNA methyltransferases. These data implicate an epigenetic mechanism in CNS repair. Folic acid and possibly other nontoxic dietary methyl donors may therefore be useful in clinical interventions to promote brain and spinal cord healing. If indeed the benefit of folate is mediated by epigenetic mechanisms that promote endogenous axonal regeneration, this provides possible avenues for new pharmacologic approaches to treating CNS injuries.

Folate regulation of axonal regeneration in the rodent central nervous system through DNA methylation

PubMed Central

Iskandar, Bermans J.; Rizk, Elias; Meier, Brenton; Hariharan, Nithya; Bottiglieri, Teodoro; Finnell, Richard H.; Jarrard, David F.; Banerjee, Ruma V.; Skene, J.H. Pate; Nelson, Aaron; Patel, Nirav; Gherasim, Carmen; Simon, Kathleen; Cook, Thomas D.; Hogan, Kirk J.

2010-01-01

The folate pathway plays a crucial role in the regeneration and repair of the adult CNS after injury. Here, we have shown in rodents that such repair occurs at least in part through DNA methylation. In animals with combined spinal cord and sciatic nerve injury, folate-mediated CNS axon regeneration was found to depend on injury-related induction of the high-affinity folate receptor 1 (Folr1). The activity of folate was dependent on its activation by the enzyme dihydrofolate reductase (Dhfr) and a functional methylation cycle. The effect of folate on the regeneration of afferent spinal neurons was biphasic and dose dependent and correlated closely over its dose range with global and gene-specific DNA methylation and with expression of both the folate receptor Folr1 and the de novo DNA methyltransferases. These data implicate an epigenetic mechanism in CNS repair. Folic acid and possibly other nontoxic dietary methyl donors may therefore be useful in clinical interventions to promote brain and spinal cord healing. If indeed the benefit of folate is mediated by epigenetic mechanisms that promote endogenous axonal regeneration, this provides possible avenues for new pharmacologic approaches to treating CNS injuries. PMID:20424322

Novel Synthetic Mono-triazole Glycosides Induce G0/G1 Cell-cycle Arrest and Apoptosis in Cholangiocarcinoma Cells.

PubMed

Obchoei, Sumalee; Saeeng, Rungnapha; Wongkham, Chaisiri; Wongkham, Sopit

2016-11-01

The treatment of cholangiocarcinoma (CCA) is still ineffective and the search for a novel treatment is needed. In this study, eight novel mono-triazole glycosides (W1-W8) were synthesized and tested for their anticancer activities in CCA cell lines. The anti-proliferation effect and the underlying mechanisms of the triazole glycosides were explored. Viable cells were determined using the MTT test. Among glycosides tested, W4 and W5 exhibited the most potent anticancer activity in a dose- and time-dependent fashion. Flow cytometry and wstern blot analysis revealed that W4 and W5 induced G 0 /G 1 phase cell-cycle arrest through down-regulation of cyclin D1, cyclin E and induction of cyclin-dependent kinase inhibitors, p27 and p21 protein expression. Annexin V/propidium iodide (PI) staining demonstrated that W4 and W5 also induced apoptotic cells in a dose-dependent manner via caspase signaling cascade. Together, these findings imply that the novel synthetic glycosides might be a promising anticancer agent for CCA. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Coffee induces breast cancer resistance protein expression in Caco-2 cells.

PubMed

Isshiki, Marina; Umezawa, Kazuo; Tamura, Hiroomi

2011-01-01

Coffee is a beverage that is consumed world-wide on a daily basis and is known to induce a series of metabolic and pharmacological effects, especially in the digestive tract. However, little is known concerning the effects of coffee on transporters in the gastrointestinal tract. To elucidate the effect of coffee on intestinal transporters, we investigated its effect on expression of the breast cancer resistance protein (BCRP/ABCG2) in a human colorectal cancer cell line, Caco-2. Coffee induced BCRP gene expression in Caco-2 cells in a coffee-dose dependent manner. Coffee treatment of Caco-2 cells also increased the level of BCRP protein, which corresponded to induction of gene expression, and also increased cellular efflux activity, as judged by Hoechst33342 accumulation. None of the major constituents of coffee tested could induce BCRP gene expression. The constituent of coffee that mediated this induction was extractable with ethyl acetate and was produced during the roasting process. Dehydromethylepoxyquinomicin (DHMEQ), an inhibitor of nuclear factor (NF)-κB, inhibited coffee-mediated induction of BCRP gene expression, suggesting involvement of NF-κB in this induction. Our data suggest that daily consumption of coffee might induce BCRP expression in the gastrointestinal tract and may affect the bioavailability of BCRP substrates.

Mechanism of enhanced hematopoietic response by soluble beta-glucan SCG in cyclophosphamide-treated mice.

PubMed

Harada, Toshie; Kawaminami, Hiromi; Miura, Noriko N; Adachi, Yoshiyuki; Nakajima, Mitsuhiro; Yadomae, Toshiro; Ohno, Naohito

2006-01-01

SCG is a major 6-branched 1,3-beta-D-glucan in Sparassis crispa Fr. SCG shows antitumor activity and also enhances the hematopoietic response in cyclophosphamide (CY)-treated mice. In the present study, the molecular mechanism of the enhancement of the hematopoietic response was investigated. The levels of interferon-(IFN-)gamma, tumor necrosis factor-(TNF-)alpha, granulocyte-macrophage-colony stimulating factor (GM-CSF), interleukin-(IL-) 6 and IL-12p70 were significantly increased by SCG in CY-treated mice. GM-CSF production in the splenocytes from the CY-treated mice was higher than that in normal mice regardless of SCG stimulation. Neutralizing GM-CSF significantly inhibited the induction of IFN-gamma, TNF-alpha and IL-12p70 by SCG. The level of cytokine induction by SCG was regulated by the amount of endogenous GM-CSF produced in response to CY treatment in a dose-dependent manner. The expression of beta-glucan receptors, such as CR3 and dectin-1, was up-regulated by CY treatment. Blocking dectin-1 significantly inhibited the induction of TNF-alpha and IL-12p70 production by SCG. Taken together, these results suggest that the key factors in the cytokine induction in CY-treated mice were the enhanced levels of both endogenous GM-CSF production and dectin-1 expression.

Diagnosis and management of primary central nervous system lymphoma.

PubMed

Han, Catherine H; Batchelor, Tracy T

2017-11-15

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive extranodal non-Hodgkin lymphoma (NHL) that is confined to the brain, eyes, spinal cord, or leptomeninges without systemic involvement. The overall prognosis, diagnosis, and management of PCNSL differ from those for other types of NHL. Prompt diagnosis and initiation of treatment are vital for improving clinical outcomes. PCNSL is responsive to radiation therapy; however, whole-brain radiotherapy (WBRT) inadequately controls the disease when it is used alone, and its delayed neurotoxicity causes neurocognitive impairment, especially in elderly patients. High-dose methotrexate (HD-MTX)-based induction chemotherapy with or without autologous stem cell transplantation (ASCT) or reduced-dose WBRT leads to durable disease control and less neurotoxicity. The optimal treatment has yet to be defined; however, HD-MTX-based induction chemotherapy is considered standard for newly diagnosed PCNSL. Ongoing randomized trials are addressing the roles of rituximab and consolidative treatment with ASCT or reduced-dose WBRT. Despite high tumor response rates with the initial treatment, many patients relapse with a very poor prognosis. The optimal treatment for refractory or relapsed PCNSL is poorly defined. The choice of salvage treatment depends on a patient's age, previous treatment and response, performance status, and comorbidities at the time of relapse. This review provides an overview of the clinical features, diagnosis, pathology, and management of PCNSL in immunocompetent patients, and it focuses on recent advances in treatment. Cancer 2017;123:4314-24. © 2017 American Cancer Society. © 2017 American Cancer Society.

Induction of extracellular ATP mediates increase in intracellular thioredoxin in RAW264.7 cells exposed to low-dose γ-rays.

PubMed

Ohshima, Yasuhiro; Kitami, Akihiro; Kawano, Ayumi; Tsukimoto, Mitsutoshi; Kojima, Shuji

2011-09-15

We previously showed that low doses (0.25-0.5 Gy) of γ-rays elevated thioredoxin (Trx-1) in various organs of mice after whole-body irradiation. Also, it is reported that extracellular ATP, which is released in response to various stresses, regulates the expression of intracellular antioxidants through activation of P2 receptors. We have recently found that low-dose γ-rays induce ATP release from the exposed cells. However, it is not yet clear whether the radiation-induced extracellular ATP modulates the cellular redox balance. Here, we investigated whether γ-ray irradiation-induced release of extracellular ATP contributes to the induction of the cellular antioxidant Trx-1, using mouse macrophage-like RAW264.7 cells. Irradiation with γ-rays or exogenously added ATP increased the expression of Trx-1, and in both cases the increase was blocked by pretreatment with an ectonucleotidase, apyrase. Then, the involvement of ATP-dependent reactive oxygen species (ROS) generation in the increase in antioxidant capacity was examined. ATP stimulation promoted the generation of intracellular ROS and also increased Trx-1 expression. The increase in Trx-1 expression was significantly suppressed by pretreatment of the cells with antioxidants. In conclusion, the γ-ray irradiation-induced release of extracellular ATP may, at least in part, contribute to the production of ROS via purinergic signaling, leading to promotion of intracellular antioxidants as an adaptive response to an oxidative stress. Copyright © 2011 Elsevier Inc. All rights reserved.

Evaluation of cytotoxic, genotoxic and inflammatory responses of micro- and nano-particles of granite on human lung fibroblast cell IMR-90.

PubMed

Ahmad, Iqbal; Khan, Mohd Imran; Patil, Govil; Chauhan, L K S

2012-02-05

Occupational exposure of granite workers is well known to cause lung impairment and silicosis. Toxicological profiles of different size particles of granite dust, however, are not yet understood. Present evaluation of micro- and nano-particles of granite dust as on human lung fibroblast cells IMR-90, revealed that their toxic effects were dose-dependent, and nanoparticles in general were more toxic. In this study we first demonstrated that nanoparticles caused oxidative stress, inflammatory response and genotoxicity, as seen by nearly 2 fold induction of ROS and LPO, mRNA levels of TNF-α and IL-1β, and induction in micronuclei formation. All these were significantly higher when compared with the effect of micro particles. Thus, the study suggests that separate health safety standards would be required for granite particles of different sizes. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Hyperforin acts as an angiogenesis inhibitor.

PubMed

Schempp, Christoph M; Kiss, Judit; Kirkin, Vladimir; Averbeck, Marco; Simon-Haarhaus, Birgit; Kremer, Bernhard; Termeer, Christian C; Sleeman, Jonathan; Simon, Jan C

2005-11-01

Hyperforin is a plant compound from Hypericum perforatum that inhibits tumor cell proliferation in vitro by induction of apoptosis. Here, we report that hyperforin also acts as an angiogenesis inhibitor in vitro and in vivo. In vitro, hyperforin blocked microvessel formation of human dermal microvascular endothelial cells (HDMEC) on a complex extracellular matrix. Furthermore, hyperforin reduced proliferation of HDMEC in a dose-dependent manner, without displaying toxic effects or inducing apoptosis of the cells. To evaluate the antiangiogenic activity of hyperforin in vivo, Wistar rats were subcutaneously injected with MT-450 mammary carcinoma cells and were treated with peritumoral injections of hyperforin or solvent. Hyperforin significantly inhibited tumor growth, induced apoptosis of tumor cells and reduced tumor vascularization, as shown by in situ staining of CD31-positive microvessels in the tumor stroma. These data suggest that, in addition to the induction of tumor cell apoptosis, hyperforin can also suppress angiogenesis by a direct, non-toxic effect on endothelial cells.

In vitro antigen-specific induction of IL-22 in human subjects that resolved HCV infection

PubMed Central

Cusick, Matthew F; Libbey, Jane E; Fujinami, Robert S; Eckels, David D

2012-01-01

Aims To determine if in vitro production of IL-22 and IL-17 correlated with resolution of HCV infection. Materials & methods Human peripheral blood cells isolated from a well-defined cohort of resolved and chronic HCV-infected subjects were used to measure HCV-, influenza- and mitogen-activated T-cell proliferation. In addition, IL-22 and IL-17 production was measured via ELISAs and flow cytometry. Results Resolved HCV subjects had a significantly higher T-cell proliferative response to recombinant NS3 protein compared with chronic HCV subjects. Resolved subjects had a dose-dependent IL-22 response to recombinant NS3 compared with chronic HCV subjects. Conclusion IL-22 production is associated with antigen-specific induction of CD4 + T cells in individuals that resolved HCV infection, suggesting a potential role for IL-22 in HCV clearance. PMID:23185211

Induction of metallothionein synthesis in transplanted murine tumors by X irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kiyoshi, Shibuya; Masahiko Satoh; Yuzo, Watanabe

1995-07-01

Although recent studies have shown that radiation can induce metallothionein (MT) synthesis in normal tissues, the induction of tumor MT synthesis by irradiation has not been reported. We examined the accumulation of MT in the Meth-A tumor (mouse fibrosarcoma cells) transplanted into mice exposed to whole-body X irradiation. In the present study, the MT content in the tumor cells was increased by X irradiation in a dose-dependent manner. The MT level induced in the tumor cells by X irradiation was elevated not only after a single exposure but also after repeated exposures. Several studies have shown that MT is onemore » of the important cellular factors in resistance to various anti-cancer drugs and ionizing radiation. Thus our results suggest that the radiation-induced MT in the tumor cells may have to be taken into consideration when designing protocols for radio-and chemotherapy. 29 refs., 3 figs.« less

Direct comparison of two different mesalamine formulations for the induction of remission in patients with ulcerative colitis: A double-blind, randomized study

PubMed Central

Ito, Hiroaki; Iida, Mitsuo; Matsumoto, Takayuki; Suzuki, Yasuo; Sasaki, Hidetaka; Yoshida, Toyomitsu; Takano, Yuichi; Hibi, Toshifumi

2010-01-01

Background: Mesalamine is the first-line drug for the treatment of ulcerative colitis (UC). We directly compared the efficacy and safety of two mesalamine formulations for the induction of remission in patients with UC. Methods: In a multicenter, double-blind, randomized study, 229 patients with mild-to-moderate active UC were assigned to 4 groups: 66 and 65 received a pH-dependent release formulation of 2.4 g/day (pH-2.4 g) or 3.6 g/day (pH-3.6 g), respectively; 65 received a time-dependent release formulation of 2.25 g/day (Time-2.25 g), and 33 received placebo (Placebo). The drugs were administered three times daily for eight weeks. The primary endpoint was a decrease in the UC disease activity index (UC-DAI). Results: In the full analysis set (n = 225) the decrease in UC-DAI in each group was 1.5 in pH-2.4 g, 2.9 in pH-3.6 g, 1.3 in Time-2.25 g and 0.3 in Placebo, respectively. These results demonstrate the superiority of pH-3.6 g over Time-2.25 g (P = 0.003) and the noninferiority of pH-2.4 g to Time-2.25 g. Among the patients with proctitis-type UC, a significant decrease in UC-DAI was observed in pH-2.4 g and pH-3.6 g as compared to Placebo, but not in Time-2.25 g. No differences were observed in the safety profiles. Conclusions: Higher dose of the pH-dependent release formulation was more effective for induction of remission in patients with mild-to-moderate active UC. Additionally, the pH-dependent release formulation was preferable to the time-dependent release formulation for patients with proctitis-type UC (UMIN Clinical Trials Registry, no. C000000288). (Inflamm Bowel Dis 2010) PMID:20049950

Effects of Taxol plus radiation on the apoptotic and mitotic indices of mouse intestinal crypt cells.

PubMed

Ozkan, L; Ozuysal, S; Egeli, U; Adim, S B; Tunca, B; Aydemir, N; Ceçener, G; Ergül, E; Akpinar, G; Cimen, C; Engin, K; Ahmed, M M

2001-07-01

In this study we investigated the effect of Taxol, radiation, or Taxol plus radiation on highly proliferative normal tissue--the intestinal crypt cells of Swiss albino mice. Swiss-albino mice, 3-4 months old, were used in this study. Taxol was administered by bolus intravenously through the tail vein. Radiation was given using a linear accelerator. There were four treatment categories, which comprised a total of 34 groups. Each group consisted of five animals. The first category was a control category which comprised one group (n = 5). The second treatment category was Taxol alone which comprised three groups (n = 15). The third treatment category was radiation alone which comprised three groups (n = 15). The fourth treatment category was Taxol plus radiation which comprised 27 groups (n = 135). Mice were killed 24 h after Taxol or radiation or combined administration using ether anesthesia. Using a light microscope, apoptotic and mitotic indices were counted on jejunal crypt cells of mice that were stained with hematoxylin-eosin. Differences between groups were statistically evaluated with Student's t-test. Taxol caused a dose-dependent increase in apoptosis (P = 0.045) and decreased the mitotic index (P = 0.006) at high doses. Similarly, radiation caused a dose-dependent increase in apoptosis (P = 0.046) and decreased the mitotic index (P = 0.299) at higher radiation doses. Compared to radiation alone, Taxol caused a significant induction of apoptosis (P = 0.010). In combination, no significant radiosensitizing effect of Taxol was observed (enhancement ratio < 1), when compared to radiation alone. However, an increase in apoptosis was observed after 24 h of Taxol exposure when compared to 12 or 48 h of Taxol exposure (P = 0.0001 and P = 0.0001). These findings suggest that Taxol did not cause a radiosensitizing effect in intestinal crypt cells. However, a 24-hour pretreatment of Taxol exposure followed by radiation caused significant induction of apoptosis and reduction of the mitotic index when compared to other Taxol timing sequences. Thus, the lack of a radiosensitizing effect of Taxol in these proliferative cells may be due to enhanced mitotic death rather than apoptotic death.

Cytochrome P450 induction by rifampicin in healthy subjects: determination using the Karolinska cocktail and the endogenous CYP3A4 marker 4beta-hydroxycholesterol.

PubMed

Kanebratt, K P; Diczfalusy, U; Bäckström, T; Sparve, E; Bredberg, E; Böttiger, Y; Andersson, T B; Bertilsson, L

2008-11-01

The Karolinska cocktail, comprising caffeine, losartan, omeprazole, and quinine, was given before and after administration of rifampicin (20, 100, or 500 mg daily) to measure induction of cytochrome P450 (P450) enzymes. Rifampicin was given for 14 days to eight healthy subjects (all of whom possessed at least one wild-type CYP2C9 and one wild-type CYP2C19 gene) in each dose group. 4beta-hydroxycholesterol was assessed as an endogenous marker of CYP3A4 induction. A fourfold induction of CYP3A4 was seen at the highest dose by both quinine:3'-hydroxyquinine and 4beta-hydroxycholesterol measurements (P < 0.001). CYP3A4 was also induced at the two lower doses of rifampicin when measured by these two markers (P < 0.01 or P < 0.001). CYP1A2, CYP2C9, and CYP2C19 were induced after 500 mg rifampicin daily (1.2-fold, P < 0.05; 1.4-fold, P < 0.05; and 4.2-fold, P < 0.01, respectively). In conclusion, we have shown that the Karolinska cocktail and 4beta-hydroxycholesterol can be used for an initial screening of the induction properties of a drug candidate.

Regulating exposure of the lens of the eye to ionising radiations.

PubMed

Thorne, M C

2012-06-01

The International Commission on Radiological Protection (ICRP) has reviewed recent epidemiological evidence suggesting that, for the lens of the eye, the threshold in absorbed dose for the induction of deleterious health effects is about 0.5 Gy. On this basis, the Commission recommends that for occupational exposure in planned exposure situations, the equivalent dose limit for the lens of the eye should be 20 mSv in a year, averaged over defined periods of 5 yr, with exposure not exceeding 50 mSv in any single year. This paper summarises the data that have been taken into account by the ICRP and critically examines whether the proposed downward revision of the dose limit is justified. Overall, it is concluded that the accumulating radiobiological and epidemiological evidence makes it more appropriate to treat cataract induction as a stochastic rather than a deterministic effect. Within this framework, it is illogical to have the same dose limit for the lens of the eye as for the whole body irradiated uniformly. This could be addressed either by removing the special dose limit for the lens of the eye, assigning it an appropriate tissue weighting factor and including it in the computation of the effective dose, or through a composite approach involving the use of a tissue weighting factor for effective dose computations together with a special limit on the equivalent dose to the lens of the eye to ensure that no individual was subject to an unacceptably high risk of induction of clinically significant cataracts.

Induction and concurrent chemotherapy with high-dose thoracic conformal radiation therapy in unresectable stage IIIA and IIIB non-small-cell lung cancer: a dose-escalation phase I trial.

PubMed

Socinski, Mark A; Morris, David E; Halle, Jan S; Moore, Dominic T; Hensing, Thomas A; Limentani, Steven A; Fraser, Robert; Tynan, Maureen; Mears, Andrea; Rivera, M Patricia; Detterbeck, Frank C; Rosenman, Julian G

2004-11-01

Local control rates at conventional radiotherapy doses (60 to 66 Gy) are poor in stage III non-small-cell lung cancer (NSCLC). Dose escalation using three-dimensional thoracic conformal radiation therapy (TCRT) is one strategy to improve local control and perhaps survival. Stage III NSCLC patients with a good performance status (PS) were treated with induction chemotherapy (carboplatin area under the curve [AUC] 5, irinotecan 100 mg/m(2), and paclitaxel 175 mg/m(2) days 1 and 22) followed by concurrent chemotherapy (carboplatin AUC 2 and paclitaxel 45 mg/m(2) weekly for 7 to 8 weeks) beginning on day 43. Pre- and postchemotherapy computed tomography scans defined the initial clinical target volume (CTV(I)) and boost clinical target volume (CTV(B)), respectively. The CTV(I) received 40 to 50 Gy; the CTV(B) received escalating doses of TCRT from 78 Gy to 82, 86, and 90 Gy. The primary objective was to escalate the TCRT dose from 78 to 90 Gy or to the maximum-tolerated dose. Twenty-nine patients were enrolled (25 assessable patients; median age, 59 years; 62% male; 45% stage IIIA; 38% PS 0; and 38% > or = 5% weight loss). Induction CIP was well tolerated (with filgrastim support) and active (partial response rate, 46.2%; stable disease, 53.8%; and early progression, 0%). The TCRT dose was escalated from 78 to 90 Gy without dose-limiting toxicity. The primary acute toxicity was esophagitis (16%, all grade 3). Late toxicity consisted of grade 2 esophageal stricture (n = 3), bronchial stenosis (n = 2), and fatal hemoptysis (n = 2). The overall response rate was 60%, with a median survival time and 1-year survival probability of 24 months and 0.73 (95% CI, 0.55 to 0.89), respectively. CONCLUSION Escalation of the TCRT dose from 78 to 90 Gy in the context of induction and concurrent chemotherapy was accomplished safely in stage III NSCLC patients.

Antioxidant and anticancer activity of Artemisia princeps var. orientalis extract in HepG2 and Hep3B hepatocellular carcinoma cells

PubMed Central

Choi, Eun-Jeong

2013-01-01

Objective The aim of the present study was to investigate antioxidant and the anticancerigen activity of a methanol extract from Artemisia princeps var. orientalis (APME), a well-known traditional herbal medicine in Asia, in hepatocellular cancer cells. Methods To evaluate the antioxidant activity of APME, reactive oxygen species (ROS) and the antioxidant enzymes, superoxide dismutase (SOD) and catalase were investigated in HepG2 cells exposed to APME (5, 100, and 200 µg/mL) for 72 h. Then, to evaluate the anticancer activity of APME, we investigated the proliferation and apoptosis induction of HepG2 and Hep3B cells exposed to APME (1-200 µg/mL) for 24, 48, and 72 h. Results APME dose-dependently reduced the generation of ROS in the presence of H2O2 compared with control cells. Furthermore, it increased catalase and SOD activity. Moreover, APME inhibited cell proliferation in a dose- and time-dependent manner, but at concentrations lower than 100 µg/mL, the inhibition was less dose-dependent than time-dependent. HepG2 and Hep3B cells exposed to 5, 100, and 200 µg/mL APME for 72 h underwent cell cycle arrest and apoptosis. Exposure to APME resulted in a significant increase in the number of cells in G1 phase and a decrease in the G2/M phase cell population. In addition, APME induced P53 expression of HepG2 cells in a dose-dependent manner, and played a role in the downregulation of Bcl-2 and upregulation of Bax in both HepG2 and Hep3B cells. Conclusions These results indicate the potential role of APME as an antioxidant and anticancerigen agent in hepatocarcinoma cell lines. PMID:24255577

Anticancer activity of Pupalia lappacea on chronic myeloid leukemia K562 cells.

PubMed

Ravi, Alvala; Alvala, Mallika; Sama, Venkatesh; Kalle, Arunasree M; Irlapati, Vamshi K; Reddy, B Madhava

2012-12-05

Cancer is one of the most prominent human diseases which has enthused scientific and commercial interest in the discovery of newer anticancer agents from natural sources. Here we demonstrated the anticancer activity of ethanolic extract of aerial parts of Pupalia lappacea (L) Juss (Amaranthaceae) (EAPL) on Chronic Myeloid Leukemia K562 cells. Antiproliferative activity of EAPL was determined by MTT assay using carvacrol as a positive control. Induction of apoptosis was studied by annexin V, mitochondrial membrane potential, caspase activation and cell cycle analysis using flow cytometer and modulation in protein levels of p53, PCNA, Bax and Bcl2 ratio, cytochrome c and cleavage of PARP were studied by Western blot analysis. The standardization of the extract was performed through reverse phase-HPLC using Rutin as biomarker. The results showed dose dependent decrease in growth of K562 cells with an IC50 of 40 ± 0.01 μg/ml by EAPL. Induction of apoptosis by EAPL was dose dependent with the activation of p53, inhibition of PCNA, decrease in Bcl2/Bax ratio, decrease in the mitochondrial membrane potential resulting in release of cytochrome c, activation of multicaspase and cleavage of PARP. Further HPLC standardization of EAPL showed presence 0.024% of Rutin. Present study significantly demonstrates anticancer activity of EAPL on Chronic Myeloid Leukemia (K562) cells which can lead to potential therapeutic agent in treating cancer. Rutin, a known anti cancer compound is being reported and quantified for the first time from EAPL.

Effect of activated autologous platelet-rich plasma on proliferation and osteogenic differentiation of human adipose-derived stem cells in vitro

PubMed Central

Xu, Fang-Tian; Li, Hong-Mian; Yin, Qing-Shui; Liang, Zhi-Jie; Huang, Min-Hong; Chi, Guang-Yi; Huang, Lu; Liu, Da-Lie; Nan, Hua

2015-01-01

To investigate whether activated autologous platelet-rich plasma (PRP) can promote proliferation and osteogenic differentiation of human adipose-derived stem cells (hASCs) in vitro. hASCs were isolated from lipo-aspirates, and characterized by specific cell markers and multilineage differentiation capacity after culturing to the 3rd passage. PRP was collected and activated from human peripheral blood of the same patient. Cultured hASCs were treated with normal osteogenic inductive media alone (group A, control) or osteogenic inductive media plus 5%, 10%, 20%, 40%PRP (group B, C, D, E, respectively). Cell proliferation was assessed by CCK-8 assay. mRNA expression of osteogenic marker genes including alkaline phosphatase (ALP), osteopontin (OPN), osteocalcin (OCN) and core binding factor alpha 1 (Cbfa1) were determined by Real-Time Quantitative PCR Analysis (qPCR). Data revealed that different concentrations of activated autologous PRP significantly promoted hASCs growth in the proliferation phase compared to the without PRP group and resulted in a dose-response relationship. At 7-d and 14-d time point of the osteogenic induced stage, ALP activity in PRP groups gradually increased with the increasing of concentrations of PRP and showed that dose-response relationship. At 21-d time point of the osteogenic induced stage, PRP groups make much more mineralization and mRNA relative expression of ALP, OPN, OCN and Cbfa1 than that without PRP groups and show that dose-response relationship. This study indicated that different concentrations of activated autologous PRP can promote cell proliferation at earlier stage and promote osteogenic differentiation at later stage of hASCs in vitro. Moreover, it displayed a dose-dependent effect of activated autologous PRP on cell proliferation and osteogenic differentiation of hASCs in vitro. PMID:25901195

The influence of sex on life shortening and tumor induction in CBA/Cne mice exposed to x rays or fission neutrons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Di Majo, V.; Coppola, M.; Rebessi, S.

1996-07-01

An experimental study of male and female CBA/Cne mice was set up at Casaccia primarily to investigate the influence of sex on long-term survival and tumor induction after exposure to high- and low-LET radiation. Mice were whole-body-irradiated at 3 months of age with fission-neutron doses of 0.1, 0.2, 0.4, 0.8, 1.2 and 1.8 Gy at the RSV-TAPIRO reactor (mean neutron energy 0.4 MeV, in terms of kerma, y{sub D} = 51.5 KeV/{mu}m), or with 250 KVp X-ray doses of 1, 3, 5 and 7 Gy. Control and irradiated animals were then followed for their entire life span. As a generalmore » finding, male CBA/Cne mice appear more susceptible to tumori-genesis than females. In particular, the incidences of induced acute myeloid leukemia and malignant lymphomas are significant only in male mice. Benign and malignant solid tumors of many types are observed in mice of both sexes, the most frequent being in the lung, liver and ovary. However, evidence for a radiation response is limited to the case of Harderian gland neoplasms. In addition, a comparison of the observed frequency of all irradiated compared to unirradiated animals bearing solid tumors shows that the total tumor occurrence is not altered markedly by radiation exposure. A decrease in survival time is observed for both sexes and radiation types and correlates well with increasing dose. Moreover, both sex and radiation quality appear to influence the life shortening. A similar dose dependence of survival time is found when tumor-free animals alone are considered, suggesting a non-specific component of life-shortening. 18 refs., 3 figs., 5 tabs.« less

Comparison of rescue techniques for failed chloral hydrate sedation for magnetic resonance imaging scans--additional chloral hydrate vs intranasal dexmedetomidine.

PubMed

Zhang, Wenhua; Wang, Zixin; Song, Xingrong; Fan, Yanting; Tian, Hang; Li, Bilian

2016-03-01

Chloral hydrate, a commonly used sedative in children during noninvasive diagnostic procedures, is associated with side effects like prolonged sedation, paradoxical excitement, delirium, and unpleasant taste. Dexmedetomidine, a highly selective α-2 agonist, has better pharmacokinetic properties than chloral hydrate. We conducted this prospective, double-blind, randomized controlled trial to evaluate efficacy of intranasal dexmedetomidine with that of a second oral dose of chloral hydrate for rescue sedation during magnetic resonance imaging (MRI) studies in infants. One hundred and fifty infants (age group: 1-6 months), who were not adequately sedated after initial oral dose of 50 mg · kg(-1) chloral hydrate, were randomly divided into three groups with the following protocol for each group. Group C: second oral dose chloral hydrate 25 mg · kg(-1); Group L and Group H: intranasal dexmedetomidine in a dosage of 1 and 2 mcg · kg(-1), respectively. Status of sedation, induction time, time to wake up, vital signs, oxygen saturation, and recovery characteristics were recorded. Successful rescue sedation in Groups C, L, and H were achieved in 40 (80%), 47 (94%), and 49 (98%) of infants, respectively, on an intention to treat analysis, and the proportion of infants successfully sedated in Group H was more than that of Group L (P ˂ 0.01). There were no significant differences in sedation induction time; however, the time to wake up was significantly shorter in Group L as compared to that in Group C or H (P < 0.01). No significant adverse hemodynamic or hypoxemic effects were observed in the study. Intranasal dexmedetomidine induced satisfactory rescue sedation in 1- to 6-month-old infants during MRI study, and appears to cause sedation in a dose-dependent manner. © 2015 John Wiley & Sons Ltd.

Potentiation of in vitro and in vivo antitumor efficacy of doxorubicin by cyclin-dependent kinase inhibitor P276-00 in human non-small cell lung cancer cells.

PubMed

Rathos, Maggie J; Khanwalkar, Harshal; Joshi, Kavita; Manohar, Sonal M; Joshi, Kalpana S

2013-01-23

In the present study, we show that the combination of doxorubicin with the cyclin-dependent kinase inhibitor P276-00 was synergistic at suboptimal doses in the non-small cell lung carcinoma (NSCLC) cell lines and induces extensive apoptosis than either drug alone in H-460 human NSCLC cells. Synergistic effects of P276-00 and doxorubicin on growth inhibition was studied using the Propidium Iodide (PI) assay. The doses showing the best synergistic effect was determined and these doses were used for further mechanistic studies such as western blotting, cell cycle analysis and RT-PCR. The in vivo efficacy of the combination was evaluated using the H-460 xenograft model. The combination of 100 nM doxorubicin followed by 1200 nM P276-00 showed synergistic effect in the p53-positive and p53-mutated cell lines H-460 and H23 respectively as compared to the p53-null cell line H1299. Abrogation of doxorubicin-induced G2/M arrest and induction of apoptosis was observed in the combination treatment. This was associated with induction of tumor suppressor protein p53 and reduction of anti-apoptotic protein Bcl-2. Furthermore, doxorubicin alone greatly induced COX-2, a NF-κB target and Cdk-1, a target of P276-00, which was downregulated by P276-00 in the combination. Doxorubicin when combined with P276-00 in a sequence-specific manner significantly inhibited tumor growth, compared with either doxorubicin or P276-00 alone in H-460 xenograft model. These findings suggest that this combination may increase the therapeutic index over doxorubicin alone and reduce systemic toxicity of doxorubicin most likely via an inhibition of doxorubicin-induced chemoresistance involving NF-κB signaling and inhibition of Cdk-1 which is involved in cell cycle progression.

Potentiation of in vitro and in vivo antitumor efficacy of doxorubicin by cyclin-dependent kinase inhibitor P276-00 in human non-small cell lung cancer cells

PubMed Central

2013-01-01

Background In the present study, we show that the combination of doxorubicin with the cyclin-dependent kinase inhibitor P276-00 was synergistic at suboptimal doses in the non-small cell lung carcinoma (NSCLC) cell lines and induces extensive apoptosis than either drug alone in H-460 human NSCLC cells. Methods Synergistic effects of P276-00 and doxorubicin on growth inhibition was studied using the Propidium Iodide (PI) assay. The doses showing the best synergistic effect was determined and these doses were used for further mechanistic studies such as western blotting, cell cycle analysis and RT-PCR. The in vivo efficacy of the combination was evaluated using the H-460 xenograft model. Results The combination of 100 nM doxorubicin followed by 1200 nM P276-00 showed synergistic effect in the p53-positive and p53-mutated cell lines H-460 and H23 respectively as compared to the p53-null cell line H1299. Abrogation of doxorubicin-induced G2/M arrest and induction of apoptosis was observed in the combination treatment. This was associated with induction of tumor suppressor protein p53 and reduction of anti-apoptotic protein Bcl-2. Furthermore, doxorubicin alone greatly induced COX-2, a NF-κB target and Cdk-1, a target of P276-00, which was downregulated by P276-00 in the combination. Doxorubicin when combined with P276-00 in a sequence-specific manner significantly inhibited tumor growth, compared with either doxorubicin or P276-00 alone in H-460 xenograft model. Conclusion These findings suggest that this combination may increase the therapeutic index over doxorubicin alone and reduce systemic toxicity of doxorubicin most likely via an inhibition of doxorubicin-induced chemoresistance involving NF-κB signaling and inhibition of Cdk-1 which is involved in cell cycle progression. PMID:23343191

Effects of caffeine on locomotor activity in streptozotocin-induced diabetic rats.

PubMed

Bădescu, S V; Tătaru, C P; Kobylinska, L; Georgescu, E L; Zahiu, D M; Zăgrean, A M; Zăgrean, L

2016-01-01

Diabetes mellitus modifies the expression of adenosine receptors in the brain. Caffeine acts as an antagonist of A1 and A2A adenosine receptors and was shown to have a dose-dependent biphasic effect on locomotion in mice. The present study investigated the link between diabetes and locomotor activity in an animal model of streptozotocin-induced diabetes, and the effects of a low-medium dose of caffeine in this relation. The locomotor activity was investigated by using Open Field Test at 6 weeks after diabetes induction and after 2 more weeks of chronic caffeine administration. Diabetes decreased locomotor activity (total distance moved and mobility time). Chronic caffeine exposure impaired the locomotor activity in control rats, but not in diabetic rats. Our data suggested that the medium doses of caffeine might block the A2A receptors, shown to have an increased density in the brain of diabetic rats, and improve or at least maintain the locomotor activity, offering a neuroprotective support in diabetic rats. Abbreviations : STZ = streptozotocin, OFT = Open Field Test.

Radioactivity of natural medicinal preparations contained extracts from peat mud available in retail trade used externally.

PubMed

Karpińska, Maria; Kapała, Jacek; Raciborska, Agnieszka; Kulesza, Grzegorz; Milewska, Anna; Mnich, Stanisław

2017-08-01

In this work were identified and measured the activity of radioactive isotopes present in medicinal preparations from peat mud and estimated the doses obtained from them during therapy. Radioactivity of 22 preparations from peat mud and 20 water samples from water of the North-East region of Poland was studied. The median of the total activity was 24.8 Bq kg -1 . Total maximal isotope activity was observed in the Iwonicka Cube 146 Bq kg -1 while considerable amounts of isotopes were found in the Kolobrzeska Peat Mud Paste 112 Bq kg -1 . The doses obtained during therapy were within the range of 11 nSv-13 μSv depending on extracts of medicinal preparations from peat mud. The probability that such a small dose would stimulate biological effects is low. However, some clinicians believe that one of the possible therapeutic mechanisms in the treatment of rheumatoid disorders is the induction of immune response by ionising radiation.

Opioid Detoxification and Naltrexone Induction Strategies: Recommendations for Clinical Practice

PubMed Central

Sigmon, Stacey C.; Bisaga, Adam; Nunes, Edward V.; O'Connor, Patrick G.; Kosten, Thomas; Woody, George

2015-01-01

Background Opioid dependence is a significant public health problem associated with high risk for relapse if treatment is not ongoing. While maintenance on opioid agonists (i.e., methadone, buprenorphine) often produces favorable outcomes, detoxification followed by treatment with the μ-opioid receptor antagonist naltrexone may offer a potentially useful alternative to agonist maintenance for some patients. Method Treatment approaches for making this transition are described here based on a literature review and solicitation of opinions from several expert clinicians and scientists regarding patient selection, level of care, and detoxification strategies. Conclusion Among the current detoxification regimens, the available clinical and scientific data suggest that the best approach may be using an initial 2–4 mg dose of buprenorphine combined with clonidine, other ancillary medications, and progressively increasing doses of oral naltrexone over 3–5 days up to the target dose of naltrexone. However, more research is needed to empirically validate the best approach for making this transition. PMID:22404717

Activation-specific metabolic requirements for NK cell IFN-γ production1

PubMed Central

Keppel, Molly P.; Topcagic, Nermina; Mah, Annelise Y.; Vogel, Tiphanie P.; Cooper, Megan A.

2014-01-01

There has been increasing recognition of the importance of cellular metabolism and metabolic substrates for the function and differentiation of immune cells. Here, for the first time, we investigate the metabolic requirements for production of IFN-γ by freshly isolated NK cells. Primary murine NK cells mainly utilize mitochondrial oxidative phosphorylation at rest and with short-term activation. Remarkably, we discovered significant differences in the metabolic requirements of murine NK cell IFN-γ production depending upon the activation signal. Stimulation of NK cell IFN-γ production was independent of glycolysis or mitochondrial oxidative phosphorylation when cells were activated with IL-12+IL-18. By contrast, stimulation via activating NK receptors required glucose-driven oxidative phosphorylation. Prolonged treatment with high-dose, but not low dose, IL-15 eliminated the metabolic requirement for receptor stimulation. In summary, this study demonstrates that metabolism provides an essential second signal for induction of IFN-γ production by activating NK cell receptors that can be reversed with prolonged high-dose IL-15 treatment. PMID:25595780

A rapid enhancement of locomotor sensitization to amphetamine by estradiol in female rats.

PubMed

Zovkic, Iva B; McCormick, Cheryl M

2017-11-14

Estradiol moderates the effects of drugs of abuse in both humans and rodents. Estradiol's enhancement of behavioral effects resulting from high (>2.5mg/kg) doses of amphetamine is established in rats; there is less evidence for the role of estradiol in locomotor effects elicited by lower doses, which are less aversive, increase incentive motivation, involve different neural mechanisms than higher doses, and often more readily reveal group differences than do higher doses. Further, the extent to which estradiol is required for the induction versus the expression of sensitization is unknown. To establish a protocol, we replicated the effects of estradiol on locomotor sensitization to amphetamine reported in a previous study that involved a high locomotor-activating dose (1.5mg/kg) of amphetamine, but with a lower dose. Ovariectomized female rats received 5μg of estradiol benzoate (EB) or OIL 30min before each of 5 treatments of 1.0mg/kg amphetamine or saline; all received a 0.5mg/kg challenge dose three days later. Compared with results for OIL, EB enhanced the locomotor-activating effects of repeated 1.0mg/kg amphetamine across treatment days. In contrast, on challenge day, there was no difference between EB-saline and EB-amphetamine to the lower dose (i.e., no sensitization). Experiments 2 and 3 involved a shorter induction (2days) and a lengthier withdrawal (9days) before the challenge test for the expression of sensitization to better differentiate the induction phase from the expression phase. In Expt2, EB-, and not OIL-, treated rats showed sensitization to 0.5mg/kg amphetamine; neither group showed sensitization to 1.5mg/kg amphetamine (ceiling effect?). In Expt3, rats were treated with EB either in both the induction and expression phases, in one of the phases only, or in neither phase. There was an effect of hormone treatment on challenge day and not on induction day; rats given EB on Challenge day showed sensitization to 0.5mg/kg amphetamine; OIL rats did not. The results suggest rapid effects of estradiol on amphetamine sensitization consistent with rapid effects of estradiol reported for other behaviours. Copyright © 2017. Published by Elsevier Inc.

Improved long-term survival after intra-operative single high-dose ATG-Fresenius induction in renal transplantation: a single centre experience.

PubMed

Kaden, Jürgen; May, Gottfried; Völp, Andreas; Wesslau, Claus

2009-01-01

In organ grafts donor-specific sensitization is initiated immediately after revascularization. Therefore, in 1990 we introduced the intra-operative single high-dose ATG-Fresenius (ATG-F) induction in addition to standard triple drug therapy (TDT) consisting of steroids, azathioprine and cyclosporin. A total of 778 first renal transplantations from deceased donors, performed between 1987 and 1998, were included in this evaluation. This retrospective analysis of clinic records and electronic databases presents data of all recipients of first kidney grafts who received two different ATG-F inductions (1(st) group: 9 mg/kg body weight as single high-dose intra-operatively, n=484; 2(nd) group: 3 mg/kg body weight on 7 or 8 consecutive days as multiple-dose starting also intra-operatively, n=78) and standard TDT alone (3(rd) group: TDT alone, n=216). The 10-year patient survival rates were 72.6+/-2.6% (TDT + ATG-F single high-dose), 79.5+/-5.1% (TDT + ATG-F multiple-dose) and 67.2+/-3.7%% (TDT alone; Kaplan-Meier estimates with standard errors; ATG-F vs TDT alone, p=0.001). The 10-year graft survival rates with censoring of patients that died with a functioning graft were 73.8+/-2.4%, 57.7+/-5.8% and 58.4+/-3.6% (Kaplan-Meier estimates with standard errors; 1(st) vs 2(nd )and 3(rd) group, respectively, p<0.001) and the 10-year graft survival rates with patient death counted as graft failure were 58.3+/-2.7%, 55.7+/-5.8% and 48.2+/-3.5% (Kaplan-Meier estimates with standard errors; ATG-F single high-dose vs TDT, p=0.023). In pre-sensitized recipients there were also significant differences in favour of ATG-F, more notably in the single high-dose ATG-F induction. A total of 69% of the patients in the two cohorts receiving ATG-F did not experience any transplant rejections compared to 56% in patients undergoing TDT alone (p=0.018). The incidence of infectious complications was comparable across all groups. According to evidence obtained from the routine documentation of 778 renal transplantations, ATG-F induction therapy administered as a part of immunosuppressive therapy significantly improves patient survival and reduces the risk of graft failure and transplant rejections.

Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand.

PubMed

Saralamma, Venu Venkatarame Gowda; Nagappan, Arulkumar; Hong, Gyeong Eun; Lee, Ho Jeong; Yumnam, Silvia; Raha, Suchismita; Heo, Jeong Doo; Lee, Sang Joon; Lee, Won Sup; Kim, Eun Hee; Kim, Gon Sup

2015-09-18

Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma). The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL) protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose) polymerase (PARP). Inhibitor studies' results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm), pro-apoptotic proteins (Bax and Bak) and anti-apoptotic protein (Bcl-xL) in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.

Dominant role of antigen dose in CD4+Foxp3+ regulatory T cell induction and expansion1

PubMed Central

Turner, Michael S.; Kane, Lawrence P.; Morel, Penelope A.

2009-01-01

The definitions of tolerogenic vs. immunogenic dendritic cells (DC) remain controversial. Immature DC have been shown to induce T regulatory cells (Treg) specific for foreign and allo-antigens. However, we have previously reported that mature DC (G4DC) prevented the onset of autoimmune diabetes whereas immature DC (GMDC) were therapeutically ineffective. In this study, islet-specific CD4+ T cells from BDC2.5 TCR Tg mice were stimulated, in the absence of exogenous cytokine, with GMDC or G4DC pulsed with high- or low-affinity antigenic peptides and examined for Treg induction. Both GMDC and G4DC presenting low peptide doses induced weak TCR signaling via the Akt/mTOR pathway, resulting in significant expansion of Foxp3+ Treg. Furthermore, unpulsed G4DC, but not GMDC, also induced Treg. High peptide doses induced strong Akt/mTOR signaling and favored the expansion of Foxp3neg Th cells. The inverse correlation of Foxp3 and Akt/mTOR signaling was also observed in DO11.10 and OT-II TCR-Tg T cells and was recapitulated with anti-CD3/CD28 stimulation in the absence of DC. IL-6 production in these cultures correlated positively with antigen dose and inversely with Treg expansion. Studies with T cells or DC from IL-6−/− mice revealed that IL-6 production by T cells was more important in the inhibition of Treg induction at low antigen doses. These studies indicate that strength of Akt/mTOR signaling, a critical T cell intrinsic determinant for Treg vs Th induction, can be controlled by adjusting the dose of antigenic peptide. Furthermore, this operates in a dominant fashion over DC phenotype and cytokine production. PMID:19801514

Mechanisms underlying cellular responses of cells from haemopoietic tissue to low

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kadhim, Munira A

2012-08-22

The above studies will provide fundamental mechanistic information relating genetic predisposition to important low dose phenomena, and will aid in the development of Department of Energy policy, as well as radiation risk policy for the public and the workplace. We believe the proposed studies accurately reflect the goals of the DOE low dose program. To accurately define the risks associated with human exposure to relevant environmental doses of low LET ionizing radiation, it is necessary to completely understand the biological effects at very low doses (i.e. less than 0.1 Gy), including the lowest possible dose, that of a single electronmore » track traversal. At such low doses, a range of studies have shown responses in biological systems which are not related to the direct interaction of radiation tracks with DNA. The role of these "non-targeted responses in critical tissues is poorly understood and little is known regarding the underlying mechanisms. Although critical for dosimetry and risk assessment, the role of individual genetic susceptibility in radiation risk is not satisfactorily defined at present. The aim of the proposed grant is to critically evaluate non-targeted effects of ionizing radiation with a focus on the induction of genomic instability (GI) in key stem cell populations from haemopoietic tissue. Using stem cells from two mouse strains (CBA/CaH and C57BL/6J) known to differ in their susceptibility to radiation effects, we plan to carefully dissect the role of genetic predisposition in these models on genomic instability. We will specifically focus on the effects of low doses of low LET radiation, down to the dose of 10mGy (0.01Gy) X-rays. Using conventional X-ray and we will be able to assess the role of genetic variation under various conditions at a range of doses down to the very low dose of 0.01Gy. Irradiations will be carried out using facilities in routine operation for such studies. Mechanistic studies of instability in different cell lineages will include the role of cytokines which have been shown to be in the initiation of instability. These studies also aim to uncover the possible mechanism of the initiation, perpetuation and delayed pathways of the instability response using relevant biological endpoints i.e. chromosomal instability, apoptosis induction, cytokine and gene array analysis. Integral to these studies will be an assessment of the role of genetic susceptibility in these responses, using CBA/CaH and C57BL/6J mice. The overall results suggest that low dose low LET X-irradiation induced delayed GI in both CBA/CaH and C57BL/6J haemopoeitic tissue. Using several biological approaches, some key strain and dose-specific differences have been identified in radiation-induced signalling in the initiation and perpetuation of the instability process. Furthermore, the induction of non-targeted radiation effects and genetic dependency may be linked to the use of alternative signalling pathways and mechanisms which have potential implications on evaluation of non-targeted effects in radiation risk assessment.« less

Modelling carcinogenesis after radiotherapy using Poisson statistics: implications for IMRT, protons and ions.

PubMed

Jones, Bleddyn

2009-06-01

Current technical radiotherapy advances aim to (a) better conform the dose contours to cancers and (b) reduce the integral dose exposure and thereby minimise unnecessary dose exposure to normal tissues unaffected by the cancer. Various types of conformal and intensity modulated radiotherapy (IMRT) using x-rays can achieve (a) while charged particle therapy (CPT)-using proton and ion beams-can achieve both (a) and (b), but at greater financial cost. Not only is the long term risk of radiation related normal tissue complications important, but so is the risk of carcinogenesis. Physical dose distribution plans can be generated to show the differences between the above techniques. IMRT is associated with a dose bath of low to medium dose due to fluence transfer: dose is effectively transferred from designated organs at risk to other areas; thus dose and risk are transferred. Many clinicians are concerned that there may be additional carcinogenesis many years after IMRT. CPT reduces the total energy deposition in the body and offers many potential advantages in terms of the prospects for better quality of life along with cancer cure. With C ions there is a tail of dose beyond the Bragg peaks, due to nuclear fragmentation; this is not found with protons. CPT generally uses higher linear energy transfer (which varies with particle and energy), which carries a higher relative risk of malignant induction, but also of cell death quantified by the relative biological effect concept, so at higher dose levels the frank development of malignancy should be reduced. Standard linear radioprotection models have been used to show a reduction in carcinogenesis risk of between two- and 15-fold depending on the CPT location. But the standard risk models make no allowance for fractionation and some have a dose limit at 4 Gy. Alternatively, tentative application of the linear quadratic model and Poissonian statistics to chromosome breakage and cell kill simultaneously allows estimation of relative changes in carcinogenesis that incorporate fractionation and relative biological effects (RBE). This alternative modelling approach allows absolute and relative risk estimations per cell and can be extended to tissues. The classical turnover point in carcinogenesis occurring after a single exposure is a feature of the model; also, the dose-response relationship becomes pseudo-linear with extended fractionation and when heterogeneity of the radiosensitivity parameters is introduced; there is also an inverse relationship between dose per fraction and cancer induction. In principle, this new approach might influence the conduct of proton and ion beam therapy, particularly beam placements and fractionation policies. The theoretical implications for future radiotherapy are considerable, but these predictions should be subjected to cellular and tissue experiments that simulate these forms of treatment, including any secondary neutron production in some cases depending on the beam delivery technique, e.g. in tissue equivalent humanoid phantoms using cell transformation techniques. Since the UK has no working high energy particle beam facility over 100 MeV, British scientists would require use of particle beam facilities in Europe, USA or Japan to perform experiments.

Management of opioid painkiller dependence in primary care: ongoing recovery with buprenorphine/naloxone

PubMed Central

Hard, Bernadette

2014-01-01

Opioid painkiller dependence is a growing problem and best-practice management is not well defined. We report a case of a young woman exhibiting dependence on codeine, originally prescribed for myalgic encephalopathy, after escalating use over a 10-year period. In 2012, a consultation with a new general practitioner, who had extensive experience of patients with substance abuse, revealed the underlying dependence. After building trust for 6 months, she was able to admit to medication abuse, and was referred to the community drug and alcohol team. On presentation to the team, the patient had no pain issues and the dihydrocodeine use—600 tablets/week—solely reflected her dependence. The patient successfully underwent rapid induction with buprenorphine/naloxone as opioid substitution treatment over 2 days. She is currently stable, engaged with recovery support services and psychosocial counselling, and has just returned to work. She is maintained on a therapeutic dose of buprenorphine 10 mg/naloxone 2.5 mg. PMID:25432908

CANCER RISKS ATTRIBUTABLE TO LOW DOSES OF IONIZING RADIATION - ASSESSING WHAT WE REALLY KNOW?

EPA Science Inventory

Cancer Risks Attributable to Low Doses of Ionizing Radiation - What Do We Really Know?

Abstract
High doses of ionizing radiation clearly produce deleterious consequences in humans including, but not exclusively, cancer induction. At very low radiation doses the situatio...

Induction of Cell Death through Alteration of Oxidants and Antioxidants in Epithelial Cells Exposed to High Energy Protons

NASA Technical Reports Server (NTRS)

Ramesh, Govindarajan; Wu, Honglu

2012-01-01

Radiation affects several cellular and molecular processes including double strand breakage, modifications of sugar moieties and bases. In outer space, protons are the primary radiation source which poses a range of potential health risks to astronauts. On the other hand, the use of proton radiation for tumor radiation therapy is increasing as it largely spares healthy tissues while killing tumor tissues. Although radiation related research has been conducted extensively, the molecular toxicology and cellular mechanisms affected by proton radiation remain poorly understood. Therefore, in the present study, we irradiated rat epithelial cells (LE) with different doses of protons and investigated their effects on cell proliferation and cell death. Our data showed an inhibition of cell proliferation in proton irradiated cells with a significant dose dependent activation and repression of reactive oxygen species (ROS) and antioxidants, glutathione and superoxide dismutase respectively as compared to control cells. In addition, apoptotic related genes such as caspase-3 and -8 activities were induced in a dose dependent manner with corresponding increased levels of DNA fragmentation in proton irradiated cells than control cells. Together, our results show that proton radiation alters oxidant and antioxidant levels in the cells to activate apoptotic pathway for cell death.

Low-dose γ-radiation inhibits IL-1β-induced dedifferentiation and inflammation of articular chondrocytes via blockage of catenin signaling

PubMed Central

Hong, Eun-Hee; Song, Jie-Young; Lee, Su-Jae; Park, In-Chul; Um, Hong-Duck; Park, Jong Kuk; Lee, Kee-Ho; Nam, Seon Young; Hwang, Sang-Gu

2014-01-01

Although low-dose radiation (LDR) regulates a wide range of biological processes, limited information is available on the effects of LDR on the chondrocyte phenotype. Here, we found that LDR, at doses of 0.5–2 centiGray (cGy), inhibited interleukin (IL)-1β-induced chondrocyte destruction without causing side effects, such as cell death and senescence. IL-1β treatment induced an increase in the expression of α-, β-, and γ-catenin proteins in chondrocytes via Akt signaling, thereby promoting dedifferentiation through catenin-dependent suppression of Sox-9 transcription factor expression and induction of inflammation through activation of the NF-κB pathway. Notably, LDR blocked cartilage disorders by inhibiting IL-1β-induced catenin signaling and subsequent catenin-dependent suppression of the Sox-9 pathway and activation of the NF-κB pathway, without directly altering catenin expression. LDR also inhibited chondrocyte destruction through the catenin pathway induced by epidermal growth factor, phorbol 12-myristate 13-acetate, and retinoic acid. Collectively, these results identify the molecular mechanisms by which LDR suppresses pathophysiological processes and establish LDR as a potentially valuable therapeutic tool for patients with cytokine- or soluble factors-mediated cartilage disorders. PMID:24604706

Exposure to sorbitol during lactation causes metabolic alterations and genotoxic effects in rat offspring.

PubMed

Cardoso, Felipe S; Araujo-Lima, Carlos F; Aiub, Claudia A F; Felzenszwalb, Israel

2016-10-17

Sorbitol is a polyol used by the food industry as a sweetener. Women are consuming diet and light products containing sorbitol during pregnancy and in the postnatal period to prevent themselves from excessive weight gain and maintain a slim body. Although there is no evidence for the genotoxicity of sorbitol in the perinatal period, this study focused on evaluating the effects of the maternal intake of sorbitol on the biochemical and toxicological parameters of lactating Wistar rat offspring after 14days of mother-to-offspring exposure. A dose-dependent reduction of offspring length was observed. An increase in sorbitol levels determined in the milk was also observed. However, we detected an inverse relationship between the exposition dose in milk fructose and triacylglycerols concentrations. There was an increase in the plasmatic levels of ALT, AST and LDLc and a decrease in proteins, cholesterol and glucose levels in the offspring. Sorbitol exposure caused hepatocyte genotoxicity, including micronuclei induction. Maternal sorbitol intake induced myelotoxicity and myelosuppression in their offspring. The Comet assay of the blood cells detected a dose-dependent genotoxic response within the sorbitol-exposed offspring. According to our results, sorbitol is able to induce important metabolic alterations and genotoxic responses in the exposed offspring. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

iNOS expression in CD4+ T cells limits Treg induction by repressing TGFβ1: combined iNOS inhibition and Treg depletion unmask endogenous antitumor immunity.

PubMed

Jayaraman, Padmini; Alfarano, Matthew G; Svider, Peter F; Parikh, Falguni; Lu, Geming; Kidwai, Sarah; Xiong, Huabao; Sikora, Andrew G

2014-12-15

Expression of inducible nitric oxide synthase (iNOS) in different cellular compartments may have divergent effects on immune function. We used a syngeneic tumor model to functionally characterize the role of iNOS in regulation of CD4(+)FOXP3(+) regulatory T cells (Treg), and optimize the beneficial effects of iNOS inhibition on antitumor immunity. Wild-type (WT) or iNOS knockout mice bearing established MT-RET-1 melanoma were treated with the small-molecule iNOS inhibitor L-NIL and/or cyclophosphamide alone or in combination. The effect of iNOS inhibition or knockout on induction of Treg from mouse and human CD4(+) T cells in ex vivo culture was determined in parallel in the presence or absence of TGFβ1-depleting antibodies, and TGFβ1 levels were assessed by ELISA. Whereas intratumoral myeloid-derived suppressor cells (MDSC) were suppressed by iNOS inhibition or knockout, systemic and intratumoral FOXP3(+) Treg levels increased in tumor-bearing mice. iNOS inhibition or knockout similarly enhanced induction of Treg from activated cultured mouse splenocytes or purified human or mouse CD4(+) T cells in a TGFβ1-dependent manner. Although either iNOS inhibition or Treg depletion with low-dose cyclophosphamide alone had little effect on growth of established MT-RET1 melanoma, combination treatment potently inhibited MDSC and Treg, boosted tumor-infiltrating CD8(+) T-cell levels, and arrested tumor growth in an immune-dependent fashion. iNOS expression in CD4(+) T cells suppresses Treg induction by inhibiting TGFβ1 production. Our data suggest that iNOS expression has divergent effects on induction of myeloid and lymphoid-derived regulatory populations, and strongly support development of combinatorial treatment approaches that target these populations simultaneously. ©2014 American Association for Cancer Research.

Out-of-field neutron and leakage photon exposures and the associated risk of second cancers in high-energy photon radiotherapy: current status.

PubMed

Takam, R; Bezak, E; Marcu, L G; Yeoh, E

2011-10-01

Determination and understanding of out-of-field neutron and photon doses in accelerator-based radiotherapy is an important issue since linear accelerators operating at high energies (>10 MV) produce secondary radiations that irradiate parts of the patient's anatomy distal to the target region, potentially resulting in detrimental health effects. This paper provides a compilation of data (technical and clinical) reported in the literature on the measurement and Monte Carlo simulations of peripheral neutron and photon doses produced from high-energy medical linear accelerators and the reported risk and/or incidence of second primary cancer of tissues distal to the target volume. Information in the tables facilitates easier identification of (1) the various methods and measurement techniques used to determine the out-of-field neutron and photon radiations, (2) reported linac-dependent out-of-field doses, and (3) the risk/incidence of second cancers after radiotherapy due to classic and modern treatment methods. Regardless of the measurement technique and type of accelerator, the neutron dose equivalent per unit photon dose ranges from as low as 0.1 mSv/Gy to as high as 20.4 mSv/Gy. This radiation dose potentially contributes to the induction of second primary cancer in normal tissues outside the treated area.

Misoprostol administered sublingually at a dose of 12.5 μg versus vaginally at a dose of 25 μg for the induction of full-term labor: a randomized controlled trial protocol.

PubMed

Gattás, Daniele Sofia Moraes Barros; da Silva Junior, José Roberto; Souza, Alex Sandro Rolland; Feitosa, Francisco Edson; de Amorim, Melania Maria Ramos

2018-04-18

Various methods are currently used for the induction of labor. Nevertheless, the most effective method with the fewest side effects remains to be established. Misoprostol, administered vaginally, has been routinely used for this purpose; however, other forms of administration are being proposed, including the use of sublingual tablets. No studies have yet compared the effectiveness and safety of 12.5-μg misoprostol administered sublingually compared to a 25-μg vaginal dose of the drug for the induction of labor. A triple-blind, multicenter, placebo-controlled, randomized clinical trial will be conducted in Brazil at the Instituto de Medicina Integral Prof. Fernando Figueira and at the Assis Chateaubriand Maternity Teaching Hospital of the Federal University of Ceará. A total of 140 patients with full-term pregnancies, a live fetus, a Bishop score ≤ 6 and a recommendation of induction of labor will be randomized to one of two groups. One group will receive 12.5-μg sublingual tablets of misoprostol and placebo vaginal tablets, while the other group will receive placebo sublingual tablets and vaginal tablets containing 25 μg of misoprostol. The principal endpoint is the rate of tachysystole. The secondary endpoints are vaginal delivery within 24 h of induction, uterine hyperstimulation, Cesarean section, severe neonatal morbidity or perinatal death, severe maternal morbidity or maternal death, and maternal preference regarding the route of administration of the drug. Student's t-test, and the chi-square test of association or Fisher's exact test, as appropriate, will be used in the data analysis. Risk ratios and their respective 95% confidence intervals will be calculated. Misoprostol has been identified as a safe, inexpensive, easily administered option for the induction of labor, with satisfactory results. An experimental study has shown that misoprostol administered sublingually at a dose of 25 μg appears to be effective and is associated with greater maternal satisfaction when labor is induced in women with an unfavorable cervix. Nevertheless, the rate of tachysystole remains high; therefore, further studies are required to determine the ideal dose and the ideal interval of time between doses. ClinicalTrial.gov, NCT01406392 .

Ling-Zhi polysaccharides potentiate cytotoxic effects of anticancer drugs against drug-resistant urothelial carcinoma cells.

PubMed

Huang, Chao-Yuan; Chen, Jeff Yi-Fu; Wu, Jia-En; Pu, Yeong-Shiau; Liu, Guang-Yaw; Pan, Min-Hsiung; Huang, Ying-Tang; Huang, A-Mei; Hwang, Chi-Ching; Chung, Shu-Ju; Hour, Tzyh-Chyuan

2010-08-11

The combined effects of ling-zhi polysaccharide fraction 3 (LZP-F3) and anticancer drugs (cisplatin and arsenic trioxide) were examined in three human urothelial carcinoma (UC) cells (parental, NTUB1; cisplatin-resistant, N/P(14); and arsenic-resistant, N/As(0.5)). MTT assay and median-effect analysis revealed that LZP-F3 could profoundly reverse the chemosensitivity of N/P(14) and N/As(0.5) to cisplatin and arsenic, respectively, in a dose-dependent manner, which involved activation of p38 and down-regulation of Akt and XPA. A dose of 10 mug/mL of LZP-F3 induced significant G1 arrest in N/P(14) and N/As(0.5) cells by flow cytometry, which may be mediated by the induction of p21(WAF1/CIP1). The combination of LZP-F3 and arsenic trioxide produced a significant synergistic growth inhibition of NTUB1 and N/As(0.5) cells. Similar results were also found in N/P(14) cells. These molecular events of combined effects involved significant and earlier induction of Fas, caspase 3 and 8 activation, Bax and Bad up-regulation, Bcl-2 and Bcl-x(L) down-regulatuion, and cytochrome c release.

Anti-inflammatory activity of Polygonum bistorta, Guaiacum officinale and Hamamelis virginiana in rats.

PubMed

Duwiejua, M; Zeitlin, I J; Waterman, P G; Gray, A I

1994-04-01

The aqueous ethanolic extracts of Polygonum bistorta L. Polygonaceae, Guaiacum officinale L. Zygophyllaceae and Hamamelis virginiana L. Hamamelidaceae were screened for anti-inflammatory activity. Administered (100 and 200 mg kg-1, p.o.) before the induction of carrageenan rat paw oedema, extracts of P. bistorta significantly suppressed both the maximal oedema response and the total oedema response (monitored as area under the time course curve). H. virginiana was inactive and G. officinale was only active at 200 mg kg-1. At 200 mg kg-1 administered before the induction of adjuvant arthritis, P. bistorta significantly inhibited both the acute and chronic phases of the adjuvant-induced rat paw swelling, while G. officinale and H. virginiana were only active against the chronic phase. Further studies on P. bistorta (100-800 mg kg-1) revealed a dose-dependent inhibition of the carrageenan-induced rat paw oedema over the dose range 100-400 mg kg-1, the E50 value being approximately 158.5 mg kg-1. The extract (200 mg kg-1), administered after the onset of the inflammatory responses reversed the course of both the carrageenan- and adjuvant-induced rat paw swelling. The results confirm that the extracts of P. bistorta, G. officinale and H. virginiana contain anti-inflammatory substances.

Induction of metallothionein in mouse cerebellum and cerebrum with low-dose thimerosal injection.

PubMed

Minami, Takeshi; Miyata, Eriko; Sakamoto, Yamato; Yamazaki, Hideo; Ichida, Seiji

2010-04-01

Thimerosal, an ethyl mercury compound, is used worldwide as a vaccine preservative. We previously observed that the mercury concentration in mouse brains did not increase with the clinical dose of thimerosal injection, but the concentration increased in the brain after the injection of thimerosal with lipopolysaccharide, even if a low dose of thimerosal was administered. Thimerosal may penetrate the brain, but is undetectable when a clinical dose of thimerosal is injected; therefore, the induction of metallothionein (MT) messenger RNA (mRNA) and protein was observed in the cerebellum and cerebrum of mice after thimerosal injection, as MT is an inducible protein. MT-1 mRNA was expressed at 6 and 9 h in both the cerebrum and cerebellum, but MT-1 mRNA expression in the cerebellum was three times higher than that in the cerebrum after the injection of 12 microg/kg thimerosal. MT-2 mRNA was not expressed until 24 h in both organs. MT-3 mRNA was expressed in the cerebellum from 6 to 15 h after the injection, but not in the cerebrum until 24 h. MT-1 and MT-3 mRNAs were expressed in the cerebellum in a dose-dependent manner. Furthermore, MT-1 protein was detected from 6 to 72 h in the cerebellum after 12 microg/kg of thimerosal was injected and peaked at 10 h. MT-2 was detected in the cerebellum only at 10 h. In the cerebrum, little MT-1 protein was detected at 10 and 24 h, and there were no peaks of MT-2 protein in the cerebrum. In conclusion, MT-1 and MT-3 mRNAs but not MT-2 mRNA are easily expressed in the cerebellum rather than in the cerebrum by the injection of low-dose thimerosal. It is thought that the cerebellum is a sensitive organ against thimerosal. As a result of the present findings, in combination with the brain pathology observed in patients diagnosed with autism, the present study helps to support the possible biological plausibility for how low-dose exposure to mercury from thimerosal-containing vaccines may be associated with autism.

Sustained Neuroprotection From a Single Intravitreal Injection of PGJ2 in a Nonhuman Primate Model of Nonarteritic Anterior Ischemic Optic Neuropathy

PubMed Central

Miller, Neil R.; Johnson, Mary A.; Nolan, Theresa; Guo, Yan; Bernstein, Alexander M.; Bernstein, Steven L.

2014-01-01

Purpose. Prostaglandin J2 (PGJ2) is neuroprotective in a murine model of nonarteritic anterior ischemic optic neuropathy (NAION). After assessing for potential toxicity, we evaluated the efficacy of a single intravitreal (IVT) injection of PGJ2 in a nonhuman primate model of NAION (pNAION). Methods. We assessed PGJ2 toxicity by administering it as a single high-dose intravenous (IV) injection, consecutive daily high-dose IV injections, or a single IVT injection in one eye of five adult rhesus monkeys. To assess efficacy, we induced pNAION in one eye of five adult male rhesus monkeys using a laser-activated rose bengal induction method. We then injected the eye with either PGJ2 or phosphate-buffered saline (PBS) intravitreally immediately or 5 hours post induction. We performed a clinical assessment, optical coherence tomography, electrophysiological testing, fundus photography, and fluorescein angiography in all animals prior to induction and at 1 day, 1 week, 2 weeks, and 4 weeks after induction. Following analysis of the first eye, we induced pNAION in the contralateral eye and then injected either PGJ2 or PBS. We euthanized all animals 5 weeks after final assessment of the fellow eye and performed both immunohistochemical and light and electron microscopic analyses of the retina and optic nerves. Results. Toxicity: PGJ2 caused no permanent systemic toxicity regardless of the amount injected or route of delivery, and there was no evidence of any ocular toxicity with the dose of PGJ2 used in efficacy studies. Transient reduction in the amplitudes of the visual evoked potentials and the N95 component of the pattern electroretinogram (PERG) occurred after both IV and IVT administration of high doses of PGJ2; however, the amplitudes returned to normal in all animals within 1 week. Efficacy: In all eyes, a single IVT dose of PGJ2 administered immediately or shortly after induction of pNAION resulted in a significant reduction of clinical, electrophysiological, and histological damage compared with vehicle-injected eyes (P = 0.03 for both VEP and PERG; P = 0.05 for axon counts). Conclusions. In nonhuman primates, PGJ2 administered either intravenously or intravitreally produces no permanent toxicity at even four times the dose given for neuroprotection. Additionally, a single IVT dose of PGJ2 is neuroprotective when administered up to 5 hours after induction of pNAION. PMID:25298416

Mutagenic effect of accelerated heavy ions on bacterial cells

NASA Astrophysics Data System (ADS)

Boreyko, A. V.; Krasavin, E. A.

2011-11-01

The heavy ion accelerators of the Joint Institute for Nuclear Research were used to study the regularities and mechanisms of formation of different types of mutations in prokaryote cells. The induction of direct (lac-, ton B-, col B) mutations for Esherichia coli cells and reverse his- → His+ mutations of Salmonella typhimurium, Bacillus subtilis cells under the action of radiation in a wide range of linear energy transfer (LET) was studied. The regularities of formation of gene and structural (tonB trp-) mutations for Esherichia coli bacteria under the action of accelerated heavy ions were studied. It was demonstrated that the rate of gene mutations as a function of the dose under the action of Γ rays and accelerated heavy ions is described by linear-quadratic functions. For structural mutations, linear "dose-effect" dependences are typical. The quadratic character of mutagenesis dose curves is determined by the "interaction" of two independent "hitting" events in the course of SOS repair of genetic structures. The conclusion made was that gene mutations under the action of accelerated heavy ions are induced by δ electron regions of charged particle tracks. The methods of SOS chromotest, SOS lux test, and λ prophage induction were used to study the regularities of SOS response of cells under the action of radiations in a wide LET range. The following proposition was substantiated: the molecular basis for formation of gene mutations are cluster single-strand DNA breaks, and that for structural mutations, double-strand DNA breaks. It was found out that the LET dependence of the relative biological efficiency of accelerated ions is described by curves with a local maximum. It was demonstrated that the biological efficiency of ionizing radiations with different physical characteristics on cells with different genotype, estimated by the lethal action, induction of gene and deletion mutations, precision excision of transposons, is determined by the specific features of energy transfer of the radiations that affect the character of induced DNA damage, and the efficiency inducible and constitutive cell repair systems. The growth of relative biological efficiency of heavy charged particles is determined by the growth of the damage yield of the DNA participating in the formation of radiation-induced effects, and higher efficiency of inducible repair systems. It was established that the LET value ( L max) for which the maximum (according to the applied irradiation criteria) coefficients of relative biological efficiency are observed varies depending on the character of the registered radiation induced effect. It was demonstrated that for gene mutations and induction of precision excision of mobile elements the values of L max are realized in a LET range of ≈20 keV/μm. For lethal effects of irradiation and induction of deletion mutations the value of L max is ≈ 100 and 50 keV/μm, respectively. The differences in the L max for the studied radiation gene effectis are determined by the different type of DNA damage participating in the mutation process. A molecular model of the formation of gene mutations in Escherichia coli cells under the action of ionizing radiation was proposed. Basic DNA radiation damage and main repair ways were considered in the framework of this model. The basis is the idea of the decisive role of mutagenic, error-prone, branch of SOS repair in fixing premutation DNA damage into point mutations. It was demonstrated that the central mechanism in this process is the formation of an inducible multi-enzymatic complex including the DNA polymerase V (Umu C), RecA-protease, SSB proteins, subunits of DNA polymerase III, performing erroneous DNA synthesis on the damaged matrix. A mathematical model of induction of gene mutations under ultraviolet cell irradiation was developed based on the molecular model.

Patient quality of life following induction of oral immunotherapy for food allergy.

PubMed

Epstein Rigbi, Na'ama; Katz, Yitzhak; Goldberg, Michael R; Levy, Michael B; Nachshon, Liat; Elizur, Arnon

2016-05-01

Patient quality of life improves following successful completion of oral immunotherapy (OIT), but the process itself might have undesirable effects. We aimed to evaluate patient quality of life following OIT initial induction. The Hebrew version of the Food Allergy Quality of Life Questionnaire-Parental Form (FAQLQ-PF) was validated and administered to the parents of children following the first week of OIT for food allergy (n = 119). Patient demographics and clinical history as well as the course of initial induction week were reviewed. Pre-OIT severity of food allergy, defined as severity of reactions due to accidental exposure to the allergenic food (anaphylactic reactions, p = 0.017; epinephrine use, p = 0.049; emergency room referrals p = 0.003; and hospital admissions, p = 0.015) and a lower number of tolerated doses during initial induction, reflective of a lower maximal tolerated dose for the different allergens (p = 0.011) were associated with worse total FAQLQ-PF scores. The number of tolerated doses during induction and pre-OIT emergency room referrals remained significantly associated with worse total score of the FAQLQ-PF on multivariate analysis (p = 0.016 and p = 0.005, respectively). The correlation between the number of tolerated doses and quality of life scores was moderate-strong primarily in children aged 6-12 years (Total score, r = -0.41, p = 0.001; Emotional Impact r = -0.42, p = 0.001; Food Anxiety, r = -0.38, p = 0.002; Social and Dietary Limitations, r = -0.33, p = 0.009). Pre-OIT reaction severity affects quality of life in both preschool and school-aged food-allergic children. In contrast, a lower maximal tolerated dose during OIT induction is associated with worse indices of quality of life primarily in children aged 6-12 years. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Induction of homologous recombination in Saccharomyces cerevisiae.

PubMed

Simon, J R; Moore, P D

1988-09-01

We have investigated the effects of UV irradiation of Saccharomyces cerevisiae in order to distinguish whether UV-induced recombination results from the induction of enzymes required for homologous recombination, or the production of substrate sites for recombination containing regions of DNA damage. We utilized split-dose experiments to investigate the induction of proteins required for survival, gene conversion, and mutation in a diploid strain of S. cerevisiae. We demonstrate that inducing doses of UV irradiation followed by a 6 h period of incubation render the cells resistant to challenge doses of UV irradiation. The effects of inducing and challenge doses of UV irradiation upon interchromosomal gene conversion and mutation are strictly additive. Using the yeast URA3 gene cloned in non-replicating single- and double-stranded plasmid vectors that integrate into chromosomal genes upon transformation, we show that UV irradiation of haploid yeast cells and homologous plasmid DNA sequences each stimulate homologous recombination approximately two-fold, and that these effects are additive. Non-specific DNA damage has little effect on the stimulation of homologous recombination, as shown by studies in which UV-irradiated heterologous DNA was included in transformation/recombination experiments. We further demonstrate that the effect of competing single- and double-stranded heterologous DNA sequences differs in UV-irradiated and unirradiated cells, suggesting an induction of recombinational machinery in UV-irradiated S. cerevisiae cells.

Reversible inhibition of the hydrocortisone induction of glycerol phosphate dehydrogenase by cytochalasin B in rat glial C6 cells. [Model for mechanisms of action of steroids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, K.; de Vellis, J.

The hydrocortisone (HC) induction of glycerol phosphate dehydrogenase in rat glial C6 cells was inhibited reversibly and in a dose-dependent manner by cytochalasin B (CB). Addition of sodium pyruvate to the culture medium did not reverse the inhibitory effect of CB, suggesting that CB did not act by blocking glucose transport. CB had no effect on basal level GPDH, and total cellular RNA, DNA or protein content. Colcemid had no effect on the induction, suggesting that the integrity of microtubules is not necessary for the induction process. CB did not alter the rate of degradation of induced GPDH nor didmore » it act as an inhibitor of general protein synthesis. CB appears to specifically inhibit GPDH synthesis whether it was given before, simultaneously or after the addition of HC to the cultures. This effect of CB is correlated with a marked decrease, up to 60 percent, in specific nuclear binding of (/sup 3/H)-HC added to the culture media, even though total cell uptake of (/sup 3/H)-HC was unaffected. According to the current model of HC action, the nuclear effect of CB would result in reduced synthesis of mRNA for GPDH. Since CB dissociated microfilaments in C6 cells, we hypothesize that microfilaments may play a role in the hormonal induction process.« less

Screening of Enzyme Biomarker for Nanotoxicity of Zinc Oxide in OREOCHROMIS MOSSAMBICUS

NASA Astrophysics Data System (ADS)

Subramanian, Periasamy; Bupesh, Giridharan

2011-06-01

Experiments were conducted to determine the effects of Zinc oxide (ZnO) nanoparticles (NPs) on fish models. Oreochromis mossambicus was orally administered with ZnO NPs (50-100 nm) once and its effects at five different concentrations (60 ppm-100 ppm) were observed for 12 days. Enzymatic assays were performed at every three days interval in the vital tissues of liver, gill, muscle and kidney. The defense enzymes, ethoxyresorufin O-deethylase (EROD) and glutathione S transferase (GST) exerted a dose dependent elevation up to 6 days. This hike then declines in higher concentrations and extended duration. Whereas the tissue damaging enzymes, glutamate oxaloacetic transaminase (GOT), glutamate pyruvic transaminase (GPT) and alkaline phosphatase (ALP) as well as the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) exhibited a dose and duration dependent increase until the end of the experiment. Among these enzymes, the antioxidant enzymes response to ZnO NP toxicity on fish showed notable continuous induction. This study demonstrates that antioxidant enzymes responses in O. mossambicus could be used as a biomarker for the early detection of nanotoxicity.

Osthole induces apoptosis, suppresses cell-cycle progression and proliferation of cancer cells.

PubMed

Jarząb, Agata; Grabarska, Aneta; Kiełbus, Michał; Jeleniewicz, Witold; Dmoszyńska-Graniczka, Magdalena; Skalicka-Woźniak, Krystyna; Sieniawska, Elwira; Polberg, Krzysztof; Stepulak, Andrzej

2014-11-01

The aim of the present study was to determine the effects of osthole on cell proliferation and viability, cell-cycle progression and induction of apoptosis in human laryngeal cancer RK33 and human medulloblastoma TE671 cell lines. Cell viability was measured by means of the MTT method and cell proliferation by the 5-bromo-2-deoxyuridine (BrdU) incorporation assay. Cell-cycle progression was determined by flow cytometry, and induction of apoptosis by release of oligonucleosomes to the cytosol. The gene expression was estimated by a quantitative polymerase chain reaction (qPCR) method. High-performance counter-current chromatography (HPCCC) was applied for isolation of osthole from fruits of Mutellina purpurea. Osthole decreased proliferation and cell viability of cancer cells in a dose-dependent manner. The tested compound induced apoptosis, increased the cell numbers in G1 and decreased cell number in S/G2 phases of the cell cycle, differentially regulating CDKN1A and TP53 gene expression depending on cancer cell type. Osthole could be considered as a potential compound for cancer therapy and chemoprevention. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Exercise promotes the expression of brain derived neurotrophic factor (BDNF) through the action of the ketone body β-hydroxybutyrate.

PubMed

Sleiman, Sama F; Henry, Jeffrey; Al-Haddad, Rami; El Hayek, Lauretta; Abou Haidar, Edwina; Stringer, Thomas; Ulja, Devyani; Karuppagounder, Saravanan S; Holson, Edward B; Ratan, Rajiv R; Ninan, Ipe; Chao, Moses V

2016-06-02

Exercise induces beneficial responses in the brain, which is accompanied by an increase in BDNF, a trophic factor associated with cognitive improvement and the alleviation of depression and anxiety. However, the exact mechanisms whereby physical exercise produces an induction in brain Bdnf gene expression are not well understood. While pharmacological doses of HDAC inhibitors exert positive effects on Bdnf gene transcription, the inhibitors represent small molecules that do not occur in vivo. Here, we report that an endogenous molecule released after exercise is capable of inducing key promoters of the Mus musculus Bdnf gene. The metabolite β-hydroxybutyrate, which increases after prolonged exercise, induces the activities of Bdnf promoters, particularly promoter I, which is activity-dependent. We have discovered that the action of β-hydroxybutyrate is specifically upon HDAC2 and HDAC3, which act upon selective Bdnf promoters. Moreover, the effects upon hippocampal Bdnf expression were observed after direct ventricular application of β-hydroxybutyrate. Electrophysiological measurements indicate that β-hydroxybutyrate causes an increase in neurotransmitter release, which is dependent upon the TrkB receptor. These results reveal an endogenous mechanism to explain how physical exercise leads to the induction of BDNF.

Indications for an inducible component of error-prone DNA repair in yeast.

PubMed

Siede, W; Eckardt, F

1984-01-01

In a thermoconditional mutant of mutagenic DNA repair (rev 2ts = rad 5-8) of Saccharomyces cerevisiae recovery of survival and mutation frequencies can be monitored by incubating UV-irradiated cells in growth medium at a permissive temperature (23 degrees C) before plating and a shift to restrictive temperature (36 degrees C). Inhibition of protein synthesis with cycloheximide during incubation at permissive conditions blocks this REV 2 dependent recovery process in stationary phase rev 2ts cells, whereas it can be reduced but not totally abolished in exponentially growing cells. These results indicate a strict dependence on post-irradiation protein synthesis in stationary phase cells and argue for a considerable constitutive level and only limited inducibility in logarithmic phase cells. The UV inducibility of the REV 2 coded function in stationary phase cells could be confirmed by analysis of the dose-response pattern of the his 5-2 reversion: in stationary phase rev 2ts cells, the quadratic component of the biphasic linear-quadratic induction kinetics found at 23 degrees C, which is interpreted as the consequence of induction of mutagenic repair, is eliminated at 36 degrees C.

LAURISTON S. TAYLOR LECTURE ON RADIATION PROTECTION AND MEASURMENTS: WHAT MAKES PARTICLE RADIATION SO EFFECTIVE?

PubMed Central

Blakely, Eleanor A.

2012-01-01

The scientific basis for the physical and biological effectiveness of particle radiations has emerged from many decades of meticulous basic research. A diverse array of biologically relevant consequences at the molecular, cellular, tissue, and organism level have been reported, but what are the key processes and mechanisms that make particle radiation so effective, and what competing processes define dose dependences? Recent studies have shown that individual genotypes control radiation-regulated genes and pathways in response to radiations of varying ionization density. The fact that densely ionizing radiations can affect different gene families than sparsely ionizing radiations, and that the effects are dose- and time-dependent has opened up new areas of future research. The complex microenvironment of the stroma, and the significant contributions of the immune response have added to our understanding of tissue-specific differences across the linear energy transfer (LET) spectrum. The importance of targeted vs. nontargeted effects remain a thorny, but elusive and important contributor to chronic low dose radiation effects of variable LET that still needs further research. The induction of cancer is also LET-dependent, suggesting different mechanisms of action across the gradient of ionization density. The focus of this 35th Lauriston S. Taylor Lecture is to chronicle the step-by-step acquisition of experimental clues that have refined our understanding of what makes particle radiation so effective, with emphasis on the example of radiation effects on the crystalline lens of the human eye. PMID:23032880

Dengue-Immune Humans Have Higher Levels of Complement-Independent Enhancing Antibody than Complement-Dependent Neutralizing Antibody.

PubMed

Yamanaka, Atsushi; Konishi, Eiji

2017-09-25

Dengue is the most important arboviral disease worldwide. We previously reported that most inhabitants of dengue-endemic countries who are naturally immune to the disease have infection-enhancing antibodies whose in vitro activity does not decrease in the presence of complement (complement-independent enhancing antibodies, or CiEAb). Here, we compared levels of CiEAb and complement-dependent neutralizing antibodies (CdNAb) in dengue-immune humans. A typical antibody dose-response pattern obtained in our assay system to measure the balance between neutralizing and enhancing antibodies showed both neutralizing and enhancing activities depending on serum dilution factor. The addition of complement to the assay system increased the activity of neutralizing antibodies at lower dilutions, indicating the presence of CdNAb. In contrast, similar dose-response curves were obtained with and without complement at higher dilutions, indicating higher levels of CiEAb than CdNAb. For experimental support for the higher CiEAb levels, a cocktail of mouse monoclonal antibodies against dengue virus type 1 was prepared. The antibody dose-response curves obtained in this assay, with or without complement, were similar to those obtained with human serum samples when a high proportion of D1-V-3H12 (an antibody exhibiting only enhancing activity and thus a model for CiEAb) was used in the cocktail. This study revealed higher-level induction of CiEAb than CdNAb in humans naturally infected with dengue viruses.

Identification of Granulocyte Colony-Stimulating Factor and Interleukin-6 as Candidate Biomarkers of CBLB502 Efficacy as a Medical Radiation Countermeasure

PubMed Central

Krivokrysenko, Vadim I.; Shakhov, Alexander N.; Singh, Vijay K.; Bone, Frederick; Kononov, Yevgeniy; Shyshynova, Inna; Cheney, Alec; Maitra, Ratan K.; Purmal, Andrei; Whitnall, Mark H.; Feinstein, Elena

2012-01-01

Given an ever-increasing risk of nuclear and radiological emergencies, there is a critical need for development of medical radiation countermeasures (MRCs) that are safe, easily administered, and effective in preventing and/or mitigating the potentially lethal tissue damage caused by acute high-dose radiation exposure. Because the efficacy of MRCs for this indication cannot be ethically tested in humans, development of such drugs is guided by the Food and Drug Administration's Animal Efficacy Rule. According to this rule, human efficacious doses can be projected from experimentally established animal efficacious doses based on the equivalence of the drug's effects on efficacy biomarkers in the respective species. Therefore, identification of efficacy biomarkers is critically important for drug development under the Animal Efficacy Rule. CBLB502 is a truncated derivative of the Salmonella flagellin protein that acts by triggering Toll-like receptor 5 (TLR5) signaling and is currently under development as a MRC. Here, we report identification of two cytokines, granulocyte colony-stimulating factor (G-CSF) and interleukin-6 (IL-6), as candidate biomarkers of CBLB502's radioprotective/mitigative efficacy. Induction of both G-CSF and IL-6 by CBLB502 1) is strictly TLR5-dependent, 2) occurs in a CBLB502 dose-dependent manner within its efficacious dose range in both nonirradiated and irradiated mammals, including nonhuman primates, and 3) is critically important for the ability of CBLB502 to rescue irradiated animals from death. After evaluation of CBLB502 effects on G-CSF and IL-6 levels in humans, these biomarkers will be useful for accurate prediction of human efficacious CBLB502 doses, a key step in the development of this prospective radiation countermeasure. PMID:22837010

Cell inactivation, repair and mutation induction in bacteria after heavy ion exposure: results from experiments at accelerators and in space.

PubMed

Horneck, G; Schafer, M; Baltschukat, K; Weisbrod, U; Micke, U; Facius, R; Bucker, H

1989-01-01

To understand the mechanisms of accelerated heavy ions on biological matter, the responses of spores of B. subtilis to this structured high LET radiation was investigated applying two different approaches. 1) By the use of the Biostack concept, the inactivation probability as a function of radial distance to single particles' trajectory (i.e. impact parameter) was determined in space experiments as well as at accelerators using low fluences of heavy ions. It was found that spores can survive even a central hit and that the effective range of inactivation extends far beyond impact parameters where inactivation by delta-ray dose would be effective. Concerning the space experiment, the inactivation cross section exceeds those from comparable accelerator experiments by roughly a factor of 20. 2) From fluence effect curves, cross sections for inactivation and mutation induction, and the efficiency of repair processes were determined. They are influenced by the ions characteristics in a complex manner. According to dependence on LET, at least 3 LET ranges can be differentiated: A low LET range (app. < 200 keV/micrometers), where cross sections for inactivation and mutation induction follow a common curve for different ions and where repair processes are effective; an intermediate LET range of the so-called saturation cross section with negligible mutagenic and repair efficiency; and a high LET range (>1000 keV/micrometers) where the biological endpoints are majorly dependent on atomic mass and energy of the ion under consideration.

A COMPREHENSIVE STUDY ON APOPTOSIS INDUCTION BY AZADIRACHTIN IN Spodoptera frugiperda CULTURED CELL LINE Sf9.

PubMed

Shu, Benshui; Wang, Wenxiang; Hu, Qingbo; Huang, Jingfei; Hu, Meiying; Zhong, Guohua

2015-07-01

The induction of apoptosis by azadirachtin, a well-known botanical tetranortriterpenoid isolated from the neem tree (Azadirachta indica A. Juss) and other members of the Meliaceae, was investigated in Spodoptera frugiperda cultured cell line (Sf9). Morphological changes in Sf9 cells treated by various concentrations of azadirachtin were observed at different times under light microscopy. Morphological and biochemical analysis indicated that Sf9 cells treated by 1.5 μg/mL azadirachtin showed typical morphological changes, which were indicative of apoptosis and a clear DNA ladder. The flow cytometry analysis showed the apoptosis rate reached a maximum value of 32.66% at 24 h with 1.5 μg/mL azadirachtin in Sf9 cells. The inhibition of Sf9 cell proliferation suggested that the effect of azadirachtin was dose dependent and the EC50 at 48 and 72 h was 2.727 × 10(-6) and 6.348 × 10(-9) μg/mL, respectively. The treatment of azadirachtin in Sf9 cells could significantly increase the activity of Sf caspase-1, but showed no effect on the activity of Topo I, suggesting that the apoptosis induced by azadirachtinin Sf9 cells is through caspase-dependent pathway. These results provided not only a series of morphological, biochemical, and toxicological comprehensive evidences for induction of apoptosis by azadirachtin, but also a reference model for screening insect cell apoptosis inducers from natural compounds. © 2015 Wiley Periodicals, Inc.

Evaluation of Granulated Lactose as a Carrier for Dry Powder Inhaler Formulations 2: Effect of Drugs and Drug Loading.

PubMed

Du, Ping; Du, Ju; Smyth, Hugh D C

2017-01-01

Previously, granulated lactose carriers were shown to improve uniformity and aerosolization of a low-dose model drug. In the present study, the blending uniformity and aerosol dispersion performance were assessed for 2 model drugs salbutamol sulfate (SS) and rifampicin (RIF), blended at high loadings (10% or 30% drug) with granulated lactose carriers. The model drug powders differed in particle size distribution, morphology, density, and surface energies. Content uniformity of RIF blends was better than that of SS. Aerosolization studies showed that all blend formulations had acceptable emitted fractions (>70%). The SS blends showed low induction-port deposition (6%-10%) compared to RIF (5%-30%). This difference was greater at high flow rates. At 90 L/min, the low induction port deposition of SS blends allowed high fine particle fraction (FPF) of 73%-81%, whereas the FPF of the RIF blends was around 43%-45% with higher induction port deposition. However, SS blends exhibited strong flow rate-dependent performance. Increasing the flow rate from 30 L/min to 90 L/min increased SS FPF from approximately 20% to 80%. Conversely, RIF blends were flow rate and drug loading independent. It was concluded that the aerosolization of high drug-loaded dry powder inhaler formulations using granulated lactose, particularly flow rate dependency, varies with active pharmaceutical ingredient properties. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Titrated propofol induction vs. continuous infusion in children undergoing magnetic resonance imaging.

PubMed

Cho, J E; Kim, W O; Chang, D J; Choi, E M; Oh, S Y; Kil, H K

2010-04-01

Propofol is the popular intravenous (i.v.) anaesthetic for paediatric sedation because of its rapid onset and recovery. We compared the efficacy and safety of a single dose and conventional infusion of propofol for sedation in children who underwent magnetic resonance imaging (MRI). This was a double-blind, randomized-controlled study. One hundred and sixty children were assigned to group I (single dose) or II (infusion). Sedation was induced with i.v. propofol 2 mg/kg, and supplemental doses of propofol 0.5 mg/kg were administered until adequate sedation was achieved. After the induction of sedation, we treated patients with a continuous infusion of normal saline at a rate of 0.3 ml/kg/h in group I and the same volume of propofol in group II. In case of inadequate sedation, additional propofol 0.5 mg/kg was administered and the infusion rate was increased by 0.05 ml/kg/h. Induction time, sedation time, recovery time, additional sedation and adverse events were recorded. Recovery time was significantly shorter in group I compared with group II [0 (0-3) vs. 1 (0-3), respectively, P<0.001]. Group I (single dose) had significantly more patients with recovery time 0 compared with group II (infusion) (65/80 vs. 36/80, respectively, P<0.001). Induction and sedation times were not significantly different between groups. There was no significant difference in the frequency of additional sedation and adverse events between groups. A single dose of propofol without a continuous infusion can provide appropriate sedation in children undergoing MRI for <30 min.

Saw palmetto ethanol extract inhibits adipocyte differentiation.

PubMed

Villaverde, Nicole; Galvis, Adriana; Marcano, Adriana; Priestap, Horacio A; Bennett, Bradley C; Barbieri, M Alejandro

2013-07-01

The fruits of saw palmetto have been used for the treatment of a variety of urinary and reproductive system problems. In this study we investigated whether the fruit extracts affect in vitro adipogenesis. Saw palmetto ethanol extract inhibited the lipid droplet accumulation by induction media in a dose-dependent manner, and it also attenuated the protein expressions of C-EBPα and PPARγ. Phosphorylation of Erk1/2 and Akt1 were also decreased by saw palmetto ethanol extract. This report suggests that saw palmetto extracts selectively affect the adipocyte differentiation through the modulation of several key factors that play a critical role during adipogenesis.

Effects of 100MeV protons delivered at 0.5 or 1cGy/min on the in vivo induction of early and delayed chromosomal damage.

PubMed

Rithidech, Kanokporn Noy; Honikel, Louise M; Reungpatthanaphong, Paiboon; Tungjai, Montree; Golightly, Marc; Whorton, Elbert B

2013-08-30

Little is known about in vivo cytogenetic effects of protons delivered at the dose and dose rates encountered in space. We determined the effects of 100MeV protons, one of the most abundant type of protons produced during solar particle events (SPE), on the induction of chromosome aberrations (CAs) in bone marrow (BM) cells collected at early (3 and 24h) and late (6 months) time-points from groups of BALB/cJ mice (a known radiosensitive strain) exposed whole-body to 0 (sham-controls), 0.5, or 1.0Gy of 100MeV protons, delivered at 0.5 or 1.0cGy/min. These doses and dose-rates are comparable to those produced during SPE events. Additionally, groups of mice were exposed to 0 or 1Gy of (137)Cs γ rays (delivered at 1cGy/min) as a reference radiation. The kinetics of formation/reduction of gamma-histone 2-AX (γH2AX) were determined in BM cells collected at 1.5, 3, and 24h post-irradiation to assess the early-response. There were five mice per treatment-group per harvest-time. Our data indicated that the kinetics of γH2AX formation/reduction differed, depending on the dose and dose rate of protons. Highly significant numbers of abnormal cells and chromatid breaks (p<0.01), related to those in sham-control groups, were detected in BM cells collected at each time-point, regardless of dose or dose-rate. The finding of significant increases in the frequencies of delayed non-clonal and clonal CAs in BM cells collected at a late time-point from exposed mice suggested that 0.5 or 1Gy of 100MeV protons is capable of inducing genomic instability in BM cells. However, the extent of effects induced by these two low dose rates was comparable. Further, the results showed that the in vivo cytogenetic effects induced by 1Gy of 100MeV protons or (137)Cs γ rays (delivered at 1cGy/min) were similar. Copyright © 2013 Elsevier B.V. All rights reserved.

Passive immunization of macaques with polyclonal anti-SHIV IgG against a heterologous tier 2 SHIV: outcome depends on IgG dose

PubMed Central

2014-01-01

Background A key goal for HIV-1 envelope immunogen design is the induction of cross-reactive neutralizing antibodies (nAbs). As AIDS vaccine recipients will not be exposed to strains exactly matching any immunogens due to multiple HIV-1 quasispecies circulating in the human population worldwide, heterologous SHIV challenges are essential for realistic vaccine efficacy testing in primates. We assessed whether polyclonal IgG, isolated from rhesus monkeys (RMs) with high-titer nAbs (termed SHIVIG), could protect RMs against the R5-tropic tier-2 SHIV-2873Nip, which was heterologous to the viruses or HIV-1 envelopes that had elicited SHIVIG. Results SHIVIG demonstrated binding to HIV Gag, Tat, and Env of different clades and competed with the broadly neutralizing antibodies b12, VRC01, 4E10, and 17b. SHIVIG neutralized tier 1 and tier 2 viruses, including SHIV-2873Nip. NK-cell depletion decreased the neutralizing activity of SHIVIG 20-fold in PBMC assays. Although SHIVIG neutralized SHIV-2873Nip in vitro, this polyclonal IgG preparation failed to prevent acquisition after repeated intrarectal low-dose virus challenges, but at a dose of 400 mg/kg, it significantly lowered peak viremia (P = 0.001). Unexpectedly, single-genome analysis revealed a higher number of transmitted variants at the low dose of 25 mg/kg, implying increased acquisition at low SHIVIG levels. In vitro, SHIVIG demonstrated complement-mediated Ab-dependent enhancement of infection (C’-ADE) at concentrations similar to those observed in plasmas of RMs treated with 25 mg/kg of SHIVIG. Conclusion Our primate model data suggest a dual role for polyclonal anti-HIV-1 Abs depending on plasma levels upon virus encounter. PMID:24444350

Passive immunization of macaques with polyclonal anti-SHIV IgG against a heterologous tier 2 SHIV: outcome depends on IgG dose.

PubMed

Sholukh, Anton M; Byrareddy, Siddappa N; Shanmuganathan, Vivekanandan; Hemashettar, Girish; Lakhashe, Samir K; Rasmussen, Robert A; Watkins, Jennifer D; Vyas, Hemant K; Thorat, Swati; Brandstoetter, Tania; Mukhtar, Muhammad M; Yoon, John K; Novembre, Francis J; Villinger, Francois; Landucci, Gary; Forthal, Donald N; Ratcliffe, Sarah; Tuero, Iskra; Robert-Guroff, Marjorie; Polonis, Victoria R; Bilska, Miroslawa; Montefiori, David C; Johnson, Welkin E; Ertl, Hildegund C; Ruprecht, Ruth M

2014-01-20

A key goal for HIV-1 envelope immunogen design is the induction of cross-reactive neutralizing antibodies (nAbs). As AIDS vaccine recipients will not be exposed to strains exactly matching any immunogens due to multiple HIV-1 quasispecies circulating in the human population worldwide, heterologous SHIV challenges are essential for realistic vaccine efficacy testing in primates. We assessed whether polyclonal IgG, isolated from rhesus monkeys (RMs) with high-titer nAbs (termed SHIVIG), could protect RMs against the R5-tropic tier-2 SHIV-2873Nip, which was heterologous to the viruses or HIV-1 envelopes that had elicited SHIVIG. SHIVIG demonstrated binding to HIV Gag, Tat, and Env of different clades and competed with the broadly neutralizing antibodies b12, VRC01, 4E10, and 17b. SHIVIG neutralized tier 1 and tier 2 viruses, including SHIV-2873Nip. NK-cell depletion decreased the neutralizing activity of SHIVIG 20-fold in PBMC assays. Although SHIVIG neutralized SHIV-2873Nip in vitro, this polyclonal IgG preparation failed to prevent acquisition after repeated intrarectal low-dose virus challenges, but at a dose of 400 mg/kg, it significantly lowered peak viremia (P = 0.001). Unexpectedly, single-genome analysis revealed a higher number of transmitted variants at the low dose of 25 mg/kg, implying increased acquisition at low SHIVIG levels. In vitro, SHIVIG demonstrated complement-mediated Ab-dependent enhancement of infection (C'-ADE) at concentrations similar to those observed in plasmas of RMs treated with 25 mg/kg of SHIVIG. Our primate model data suggest a dual role for polyclonal anti-HIV-1 Abs depending on plasma levels upon virus encounter.

Combination of Nigella sativa with Glycyrrhiza glabra and Zingiber officinale augments their protective effects on doxorubicin-induced toxicity in h9c2 cells.

PubMed

Hosseini, Azar; Shafiee-Nick, Reza; Mousavi, Seyed Hadi

2014-12-01

The use of doxorubicin (DOX) is limited by its dose-dependent cardio toxicity in which reactive Oxygen Species (ROS) play an important role in the pathological process. The aim of this study was to evaluate the protective effect of three medicinal plants, Nigella sativa (N), Glycyrrhiza glabra (G) and Zingiber officinale (Z), and their combination (NGZ), against DOX-induced apoptosis and death in H9c2 cells. The cells were incubated with different concentrations of each extract or NGZ for 4 hr which continued in the presence or absence of 5µM doxorubicin for 24 hr. Cell viability and the apoptotic rate were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) and propidium iodide (PI) staining assays, respectively. The level of ROS and lipid peroxidation were measured by fluorimetric methods. Treatment with doxorubicin increased ROS generation, enhanced malondialdehyde (MDA) formation, and induced apoptosis. Co-treatment of the cells with each herb extract increased viability of cells dose-dependently with a maximum protection effect of about 30%, and their potencies were N>G>Z. The combination of the threshold dose of each extract (NGZ) produced a similar effect, which was increased dose-dependently to a maximum protection of 70%. These effects were correlated with the effects of NGZ on ROS and MDA. All of the extracts have some protective effects against DOX-induced toxicity in cardiomyocytes with similar efficacies, but with different potencies. However, NGZ produced much higher protective effect via reducing oxidative stress and inhibiting of apoptotic induction processes. Further investigations are needed to determine the effects of NGZ on DOX chemotherapy.

Combination of Nigella sativa with Glycyrrhiza glabra and Zingiber officinale augments their protective effects on doxorubicin-induced toxicity in h9c2 cells

PubMed Central

Hosseini, Azar; Shafiee-Nick, Reza; Mousavi, Seyed Hadi

2014-01-01

Objective(s): The use of doxorubicin (DOX) is limited by its dose-dependent cardio toxicity in which reactive Oxygen Species (ROS) play an important role in the pathological process. The aim of this study was to evaluate the protective effect of three medicinal plants, Nigella sativa (N), Glycyrrhiza glabra (G) and Zingiber officinale (Z), and their combination (NGZ), against DOX-induced apoptosis and death in H9c2 cells. Materials and Methods: The cells were incubated with different concentrations of each extract or NGZ for 4 hr which continued in the presence or absence of 5µM doxorubicin for 24 hr. Cell viability and the apoptotic rate were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) and propidium iodide (PI) staining assays, respectively. The level of ROS and lipid peroxidation were measured by fluorimetric methods. Results: Treatment with doxorubicin increased ROS generation, enhanced malondialdehyde (MDA) formation, and induced apoptosis. Co-treatment of the cells with each herb extract increased viability of cells dose-dependently with a maximum protection effect of about 30%, and their potencies were N>G>Z. The combination of the threshold dose of each extract (NGZ) produced a similar effect, which was increased dose-dependently to a maximum protection of 70%. These effects were correlated with the effects of NGZ on ROS and MDA. Conclusion: All of the extracts have some protective effects against DOX-induced toxicity in cardiomyocytes with similar efficacies, but with different potencies. However, NGZ produced much higher protective effect via reducing oxidative stress and inhibiting of apoptotic induction processes. Further investigations are needed to determine the effects of NGZ on DOX chemotherapy. PMID:25859303

Generation of oxyradicals (O2. and H2O2), mitochondrial activity and induction of apoptosis of PBMC of Cyprinus carpio carpio treated in vivo with halomethanes and with recombinant HSP60 kDa and with LPS of Klebsiella pneumoniae.

PubMed

Uraga-Tovar, D Italibi; Domínguez-López, M Lilia; Madera-Sandoval, Ruth L; Nájera-Martínez, Minerva; García-Latorre, Ethel; Vega-López, Armando

2014-10-01

Halomethanes (HM) can be immunotoxic in mammals; however, in the fish immune system HM effects are unknown. In the current study, we evaluated the mitochondrial activity (MA) by MTT, induction of apoptosis by SubG0 technique and quantified serum ROS concentration (O2. and H2O2) and ROS production in PBMC of Cyprinus carpio carpio treated i.p. with CH2Cl2, CHCl3 and BrCHCl2 (0.004-40.0 mg/kg) for 96 h. Positive controls were recombinant heat shock protein of 60 kDa (rHSP60 kDa) of Klebsiella pneumoniae and its LPS. In addition, for in vitro PBMC cultures, two culture media and two sources of sera were tested. Both positive controls increased the MA more than 4-fold as well as the production of O2. (26-fold) and H2O2 (5-fold) compared to their controls. HM induced different effects on MA, ROS production and an induction of apoptosis, depending on the chlorination patterns and the dose; however, a systemic damage prevails. To fish treated with CH2Cl2, the apoptosis was related with serum ROS concentration and with MA. In contrast, in fish dosed with CHCl3 relationships were not found, deducing a systemic damage. However, in fish treated with BrCHCl2, serum O2. concentration and in vitro ROS generation performed by PBMC were involved in the induction of apoptosis of these cells but not with MA suggesting also immunotoxic effects. The current study demonstrated that HMs are immunomodulators increasing an acute inflammatory response and that rHSP60kDA of K. pneumoniae and its LPS are appropriate antigens to assess the immune response of C. c. carpio.

Comparative investigations of sodium arsenite, arsenic trioxide and cadmium sulphate in combination with gamma-radiation on apoptosis, micronuclei induction and DNA damage in a human lymphoblastoid cell line.

PubMed

Hornhardt, Sabine; Gomolka, Maria; Walsh, Linda; Jung, Thomas

2006-08-30

In the field of radiation protection the combined exposure to radiation and other toxic agents is recognised as an important research area. To elucidate the basic mechanisms of simultaneous exposure, the interaction of the carcinogens and environmental toxicants cadmium and two arsenic compounds, arsenite and arsenic trioxide, in combination with gamma-radiation in human lymphoblastoid cells (TK6) were investigated. Gamma-radiation induced significant genotoxic effects such as micronuclei formation, DNA damage and apoptosis, whereas arsenic and cadmium had no significant effect on these indicators of cellular damage at non-toxic concentrations. However, in combination with gamma-radiation arsenic trioxide induced a more than additive apoptotic rate compared to the sum of the single effects. Here, the level of apoptotic cells was increased, in a dose-dependent way, up to two-fold compared to the irradiated control cells. Arsenite did not induce a significant additive effect at any of the concentrations or radiation doses tested. On the other hand, arsenic trioxide was less effective than arsenite in the induction of DNA protein cross-links. These data indicate that the two arsenic compounds interact through different pathways in the cell. Cadmium sulphate, like arsenite, had no significant effect on apoptosis in combination with gamma-radiation at low concentrations and, at high concentrations, even reduced the radiation-induced apoptosis. An additive effect on micronuclei induction was observed with 1muM cadmium sulphate with an increase of up to 80% compared to the irradiated control cells. Toxic concentrations of cadmium and arsenic trioxide seemed to reduce micronuclei induction. The results presented here indicate that relatively low concentrations of arsenic and cadmium, close to those occuring in nature, may interfere with radiation effects. Differences in action of the two arsenic compounds were identified.

A Review: Development of a Microdose Model for Analysis of Adaptive Response and Bystander Dose Response Behavior

PubMed Central

Leonard, Bobby E.

2008-01-01

Prior work has provided incremental phases to a microdosimetry modeling program to describe the dose response behavior of the radio-protective adaptive response effect. We have here consolidated these prior works (Leonard 2000, 2005, 2007a, 2007b, 2007c) to provide a composite, comprehensive Microdose Model that is also herein modified to include the bystander effect. The nomenclature for the model is also standardized for the benefit of the experimental cellular radio-biologist. It extends the prior work to explicitly encompass separately the analysis of experimental data that is 1.) only dose dependent and reflecting only adaptive response radio-protection, 2.) both dose and dose-rate dependent data and reflecting only adaptive response radio-protection for spontaneous and challenge dose damage, 3.) only dose dependent data and reflecting both bystander deleterious damage and adaptive response radio-protection (AR-BE model). The Appendix cites the various applications of the model. Here we have used the Microdose Model to analyze the, much more human risk significant, Elmore et al (2006) data for the dose and dose rate influence on the adaptive response radio-protective behavior of HeLa x Skin cells for naturally occurring, spontaneous chromosome damage from a Brachytherapy type 125I photon radiation source. We have also applied the AR-BE Microdose Model to the Chromosome inversion data of Hooker et al (2004) reflecting both low LET bystander and adaptive response effects. The micro-beam facility data of Miller et al (1999), Nagasawa and Little (1999) and Zhou et al (2003) is also examined. For the Zhou et al (2003) data, we use the AR-BE model to estimate the threshold for adaptive response reduction of the bystander effect. The mammogram and diagnostic X-ray induction of AR and protective BE are observed. We show that bystander damage is reduced in the similar manner as spontaneous and challenge dose damage as shown by the Azzam et al (1996) data. We cite primary unresolved questions regarding adaptive response behavior and bystander behavior. The five features of major significance provided by the Microdose Model so far are 1.) Single Specific Energy Hits initiate Adaptive Response, 2.) Mammogram and diagnostic X-rays induce a protective Bystander Effect as well as Adaptive Response radio-protection. 3.) For mammogram X-rays the Adaptive Response protection is retained at high primer dose levels. 4.) The dose range of the AR protection depends on the value of the Specific Energy per Hit, . 5.) Alpha particle induced deleterious Bystander damage is modulated by low LET radiation. PMID:18648579

Treatment of Opioid Dependent Pregnant Women: Clinical and Research Issues

PubMed Central

Jones, H.E.; Martin, P.R.; Heil, S.H.; Stine, S.M.; Kaltenbach, K.; Selby, P.; Coyle, M.G.; O’Grady, K.E.; Arria, A.M.; Fischer, G.

2008-01-01

This paper addresses common questions that clinicians face when treating pregnant women with opioid dependence. Guidance is provided to aid clinical decision-making, based on both research evidence and the collective clinical experience of the authors which include investigators in the Maternal Opioid Treatment: Human Experimental Research (MOTHER) project. MOTHER is a double-blind, double-dummy, flexible–dosing, parallel-group clinical trial examining the comparative safety and efficacy of methadone and buprenorphine for the opioid dependence treatment among pregnant women and their neonates. The paper begins with a discussion of appropriate assessment during pregnancy, and then addresses clinical management stages, including maintenance medication selection, induction and stabilization, opioid agonist medication management before, during and after delivery, pain management, breast-feeding, and transfer to aftercare. Lastly, other important clinical issues including managing co-occurring psychiatric disorders and medication interactions are discussed. PMID:18248941

Single-dose rATG induction at renal transplantation: superior renal function and glucoregulation with less hypomagnesemia.

PubMed

Stevens, R Brian; Lane, James T; Boerner, Brian P; Miles, Clifford D; Rigley, Theodore H; Sandoz, John P; Nielsen, Kathleen J; Skorupa, Jill Y; Skorupa, Anna J; Kaplan, Bruce; Wrenshall, Lucile E

2012-01-01

Rabbit anti-thymocyte globulin (rATG) induction reduces reperfusion injury and improves renal function in kidney recipients by means of properties unrelated to T-cell lysis. Here, we analyze intensive rATG induction (single dose, rATG(S) , vs. divided dose, rATG(D) ) for improved renal function and protection against hyperglycemia. Patients without diabetes (n = 98 of 180) in a prospective randomized trial of intensive rATG induction were followed for six months for the major secondary composite end point of impaired glucose regulation (hyperglycemia and new-onset diabetes after transplantation, NODAT). Prospectively collected data included fasting blood glucose and HbA(1c). Serum Mg(++) was routinely collected and retrospectively analyzed. Induction with rATG(S) produced less impaired glucose regulation (p = 0.05), delayed NODAT development (p = 0.02), less hyperglycemia (p = 0.02), better renal function (p = 0.04), and less hypomagnesemia (p = 0.02), a factor associated with a lower incidence of NODAT. Generalized linear modeling confirmed that rATG(S) protects against a synergistic interaction between tacrolimus and sirolimus that otherwise increased hypomagnesemia (p = 0.008) and hyperglycemia (p = 0.03). rATG(S) initiated before renal reperfusion improved early renal function and reduced impaired glucose regulation, an injury by diabetogenic maintenance agents (tacrolimus and sirolimus). © 2011 John Wiley & Sons A/S.

Dexmedetomidine reduces pain associated with rocuronium injection without causing a decrease in BIS values: a dose-response study.

PubMed

Joo, Jin; Baek, Jungwon; Lee, Jaemin

2014-09-01

To examine whether dexmedetomidine reduces the injection pain of propofol and rocuronium and to investigate whether the decrease in injection pain is associated with the known sedative action of dexmedetomidine. Randomized, double-blind, placebo-controlled clinical comparison study. Patients undergoing general anesthesia with intubation received 40 mg of 1% lidocaine (lidocaine group; n = 28), 0.25 μg/kg of dexmedetomidine (low-dose group; n = 27), 0.5 μg/kg of dexmedetomidine (subclinical dose group; n = 28), 1.0 μg/kg of dexmedetomidine (clinical dose group, n = 27), or normal saline (saline group; n = 28) before anesthetic induction. Pain associated with propofol and rocuronium injection was assessed using a 10-point verbal analog scale (VAS) and a 4-point withdrawal movement scale, respectively. The BIS value was measured 60 seconds after administration of the study drug, and at the time of rocuronium injection and intubation. The overall incidence of withdrawal movements due to rocuronium decreased significantly as the dose of dexmedetomidine increased (92.8%, 85.2%, 78.6%, and 51.9% in the saline, low-dose, subclinical dose, and clinical dose groups, respectively; P = 0.001). There was no significant difference in BIS values among the groups 60 seconds after study drug administration or at the time of rocuronium injection. Dexmedetomidine reduced pain associated with rocuronium injection in a dose-dependent manner. This effect was not associated with the decrease in BIS value. Copyright © 2014 Elsevier Inc. All rights reserved.

Mutation induction in bacteria after heavy ion irradiation

NASA Technical Reports Server (NTRS)

Horneck, G.; Kozubek, S.

1994-01-01

From a compilation of experimental data on the mutagenic effects of heavy ions in bacteria, main conclusions have been drawn as follows: (1) The mutagenic efficacy of heavy ions in bacteria depends on physical and biological variables. Physical variables are the radiation dose, energy and charge of the ion; the biological variables are the bacterial strain, the repair genotype of bacteria, and the endpoint investigated (type of mutation, induction of enzymes related to mutagenesis); (2) The responses on dose or fluence are mainly linear or linear quadratic. The quadratic component, if found for low LET radiation, is gradually reduced with increasing LET; (3) At low values of Z and LET the cross section of mutation induction sigma m (as well as SOS response, sigma sos. and lambda phage induction, sigma lambda versus LET curves can be quite consistently described by a common function which increases up to approximately 100 keV/mu m. For higher LET values, the sigma(m) versus LET curves show the so-called 'hooks' observed also for other endpoints; (4) For light ions (Z is less than or equal to 4), the cross sections mostly decrease with increasing ion energy, which is probably related to the decrease of the specific energy departed by the ion inside the sensitive volume (cell). For ions in the range of Z = 10, sigma(m) is nearly independent on the ion energy. For heavier ions (Z is greater than or equal to 16), sigma(m) increases with the energy up to a maximum or saturation around 10 MeV/u. The increment becomes steeper with increasing atomic number of the ion. It correlates with the increasing track radius of the heavy ion; (5) The mutagenic efficiency per lethal event changes slightly with ion energy, if Z is small indicating a rough correlation between cellular lethality and mutation induction, only. For ions of higher Z this relation increases with energy, indicating a change in the 'mode' of radiation action from 'killing-prone' to 'mutation-prone'; and (6) Repair genotype substantially influences the radiation induced mutagenesis. Different mechanisms of mutation induction and/or different types of biologically significant lesions in wild type cells compared to repair deficient strains are a likely explanation.

Effects of acepromazine and trazodone on anesthetic induction dose of propofol and cardiovascular variables in dogs undergoing general anesthesia for orthopedic surgery.

PubMed

Murphy, Lindsey A; Barletta, Michele; Graham, Lynelle F; Reichl, Lorna J; Duxbury, Margaret M; Quandt, Jane E

2017-02-15

OBJECTIVE To compare the doses of propofol required to induce general anesthesia in dogs premedicated with acepromazine maleate or trazodone hydrochloride and compare the effects of these premedicants on cardiovascular variables in dogs anesthetized for orthopedic surgery. DESIGN Prospective, randomized study. ANIMALS 30 systemically healthy client-owned dogs. PROCEDURES 15 dogs received acepromazine (0.01 to 0.03 mg/kg [0.005 to 0.014 mg/lb], IM) 30 minutes before anesthetic induction and 15 received trazodone (5 mg/kg [2.27 mg/lb] for patients > 10 kg or 7 mg/kg [3.18 mg/lb] for patients ≤ 10 kg, PO) 2 hours before induction. Both groups received morphine sulfate (1 mg/kg [0.45 mg/lb], IM) 30 minutes before induction. Anesthesia was induced with propofol (4 to 6 mg/kg [1.82 to 2.73 mg/lb], IV, to effect) and maintained with isoflurane or sevoflurane in oxygen. Bupivacaine (0.5 mg/kg [0.227 mg/lb]) and morphine (0.1 mg/kg [0.045 mg/lb]) were administered epidurally. Dogs underwent tibial plateau leveling osteotomy (n = 22) or tibial tuberosity advancement (8) and were monitored throughout anesthesia. Propofol induction doses and cardiovascular variables (heart rate and systemic, mean, and diastolic arterial blood pressures) were compared between groups. RESULTS The mean dose of propofol required for anesthetic induction and all cardiovascular variables evaluated did not differ between groups. Intraoperative hypotension developed in 6 and 5 dogs of the acepromazine and trazodone groups, respectively; bradycardia requiring intervention developed in 3 dogs/group. One dog that received trazodone had priapism 24 hours later and was treated successfully. No other adverse effects were reported. CONCLUSIONS AND CLINICAL RELEVANCE At the described dosages, cardiovascular effects of trazodone were similar to those of acepromazine in healthy dogs undergoing anesthesia for orthopedic surgery.

Efficacy of alfaxalone for intravascular anesthesia and euthanasia in blue crabs (Callinectes sapidus).

PubMed

Minter, Larry J; Harms, Craig A; Archibald, Kate E; Broadhurst, Heather; Bailey, Kate M; Christiansen, Emily F; Lewbart, Gregory A; Posner, Lysa P

2013-09-01

The objective of this study was to characterize the behavioral effects and changes in heart rate of four doses of alfaxalone delivered by intravascular injection to blue crabs (Callinectes sapidus). Thirty (male, n = 27; female, n = 3) blue crabs were randomly assigned to one of four treatment groups of alfaxalone: eight animals were assigned to each of the 5-, 10-, and 15-mg/kg treatment groups, and the remaining six animals were assigned to the 100-mg/kg group. Times for anesthetic induction and recovery periods were recorded. Righting reflex, defensive posturing, and heart rate were evaluated before, during, and after the anesthetic trial. Anesthesia was induced in all 14 animals consolidated into the high-dosage group (15 mg/kg [n = 8] and 100 mg/kg [n = 6]), which was significantly greater than 8 of 16 animals in the low-dosage group (5 mg/kg [n = 2] and 10 mg/kg [n = 6]). Median anesthesia induction time for all crabs was 0.4 min, with no significant difference in induction time between groups observed. Median recovery time was 9.4 min (n = 2), 6.1 min (n = 5), 11.3 min (n = 8), and 66.1 min (n = 5) for the 5-, 10-, 15-, and 100-mg/kg groups, respectively. Recovery times were significantly longer for crabs exposed to an induction dose of 100 mg/kg compared with the 10- and 15-mg/kg induction doses. A significant decrease in the median heart rate was observed between the baseline value and that observed at both induction and 5 min postinjection in the 100-mg/kg dose trial. Two mortalities were observed during the anesthesia trials (n = 1, 10 mg/kg; n = 1, 100 mg/kg), both associated with the autotomization of limbs. In summary, the intravascular administration of alfaxalone at 15 mg/kg provided rapid and reliable sedation, whereas alfaxalone administered at 100 mg/kg produced rapid and long lasting anesthesia.

Chemoprevention by Quercetin of Oral Squamous Cell Carcinoma by Suppression of the NF-κB Signaling Pathway in DMBA-treated Hamsters.

PubMed

Zhang, Wen; Yin, Gang; Dai, Jianguo; Sun, Y U; Hoffman, Robert M; Yang, Zhijian; Fan, Yuan

2017-08-01

The aim of this study was to investigate the effects of the flavonoid quercetin on chemoprevention of oral squamous cell carcinoma (OSCC). The study involved molecular signaling pathways in 7,12-dimethylbenz(a) anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. DMBA (0.5%) was painted at the right buccal pouches of hamsters for 14 weeks to induce carcinoma. DMBA-treated hamsters received simultaneous doses of quercetin. Animals without DMBA induction were used as normal controls. The incidence of OSCC and the severity of pre-malignant lesions were determined histologically. Apoptosis in the pouch tissue was determined by TUNEL staining. The mRNA and protein expression of NF-κB p50 and p65, as well as Bcl-2 and Bax genes were analyzed using RT-PCR and Western blotting, respectively. Quercetin, at various doses, significantly reduced OSCC incidence and severity of hyperplasia and dysplasia compared to the DMBA-induction-only group (p<0.01). Apoptosis was induced by quercetin treatment compared to the DMBA-induction-only group (p<0.01). mRNA and protein expression of NF-κB p50, p65 as well as Bcl-2 genes were significantly suppressed by quercetin at high doses compared to DMBA induction only (p<0.05). However, mRNA and protein expression of the Bax gene was increased by quercetin treatment at medium and high doses, compared to the DMBA-induction-only group (p<0.05). Quercetin significantly reduced body-weight loss compared to the DMBA-induction-only group (p<0.05). Quercetin reduced tumor incidence and induced apoptosis through modulation of NF-κB signaling and its target genes Bcl-2 and Bax in the DMBA-induced carcigenesis hamster model, suggesting the potential of quercetin as a candidate for OSCC chemoprevention. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Randomized trial of single-dose versus divided-dose rabbit anti-thymocyte globulin induction in renal transplantation: an interim report.

PubMed

Stevens, R Brian; Mercer, David F; Grant, Wendy J; Freifeld, Alison G; Lane, James T; Groggel, Gerald C; Rigley, Theodore H; Nielsen, Kathleen J; Henning, Megan E; Skorupa, Jill Y; Skorupa, Anna J; Christensen, Kecia A; Sandoz, John P; Kellogg, Anna M; Langnas, Alan N; Wrenshall, Lucile E

2008-05-27

The optimal dosing protocol for rabbit anti-thymocyte globulin (rATG) induction in renal transplantation has not been determined, but evidence exists that rATG infusion before renal allograft reperfusion improves early graft function. Infusing a large rATG dose over a short interval has not previously been evaluated for its effect on renal function and allograft nephropathy in a prospective, randomized comparison against conventional rATG induction. Between April 20, 2004 and December 26, 2007 we enrolled renal transplant patients into a prospective, randomized, nonblinded trial of two rATG dosing protocols (single dose, 6 mg/kg vs. divided doses, 1.5 mg/kg every other day x 4; target enrollment=160) followed after 6 months by calcineurin-inhibitor withdrawal. Primary endpoints are renal function by calculated glomerular filtration rate (GFR) and chronic allograft nephropathy at protocol biopsy. We now present the early GFR data of all 160 patients and safety and efficacy data of the first 142 patients with 6 months follow up and before calcineurin inhibitor withdrawal (average follow up=23.3+/-11.6 months). There were no differences between groups in rATG-related adverse events, patient and graft survival, acute rejection, or chronic allograft nephropathy rate at 6 months. Calculated DeltaGFR (POD 1-4) was significantly better in the single-dose group (P=0.02), with a trend toward improved renal function from months 2 to 6 in recipients of deceased donor kidneys (P=0.08). This study demonstrates that administering 6 mg/kg of rATG over 24 hr is safe and is associated with improved early renal function compared with administering rATG in alternate-day doses.

A PBPK Model to Predict Disposition of CYP3A-Metabolized Drugs in Pregnant Women: Verification and Discerning the Site of CYP3A Induction

PubMed Central

Ke, A B; Nallani, S C; Zhao, P; Rostami-Hodjegan, A; Unadkat, J D

2012-01-01

Besides logistical and ethical concerns, evaluation of safety and efficacy of medications in pregnant women is complicated by marked changes in pharmacokinetics (PK) of drugs. For example, CYP3A activity is induced during the third trimester (T3). We explored whether a previously published physiologically based pharmacokinetic (PBPK) model could quantitatively predict PK profiles of CYP3A-metabolized drugs during T3, and discern the site of CYP3A induction (i.e., liver, intestine, or both). The model accounted for gestational age-dependent changes in maternal physiological function and hepatic CYP3A activity. For model verification, mean plasma area under the curve (AUC), peak plasma concentration (Cmax), and trough plasma concentration (Cmin) of midazolam (MDZ), nifedipine (NIF), and indinavir (IDV) were predicted and compared with published studies. The PBPK model successfully predicted MDZ, NIF, and IDV disposition during T3. A sensitivity analysis suggested that CYP3A induction in T3 is most likely hepatic and not intestinal. Our PBPK model is a useful tool to evaluate different dosing regimens during T3 for drugs cleared primarily via CYP3A metabolism. PMID:23835883

Primula auriculata Extracts Exert Cytotoxic and Apoptotic Effects against HT-29 Human Colon Adenocarcinoma Cells.

PubMed

Behzad, Sahar; Ebrahim, Karim; Mosaddegh, Mahmoud; Haeri, Ali

2016-01-01

Primula auriculata (Tootia) is one of the most important local medicinal plants in Hamedan district, Iran. To investigate cytotoxicity and apoptosis induction of crude methanolic extract and different fraction of it, we compared several methods on HT-29 human colon Adenocarcinoma cells. Cancer cell proliferation was measured by 3-(4, 5‑dimethylthiazolyl)2, 5‑diphenyl‑tetrazolium bromide (MTT) assay and apoptosis induction was analyzed by fluorescence microscopy (acridin orange/ethidium bromide, annexin V/propidium iodide staining, TUNEL assay and Caspase-3 activity assay). Crude methanolic extract (CM) inhibited the growth of malignant cells in a dose-dependent manner. Among solvent fractions, the dichloromethane fraction (CF) was found to be the most toxic compared to other fractions. With double staining methods, high percentage of 40 µg/mL of (CM) and (CF) treated cells exhibited typical characteristics of apoptotic cells. Apoptosis induction was also revealed by apoptotic fragmentation of nuclear DNA and activation of caspas-3 in treated cells. These findings indicate that crude methanolic extract and dichloromethan fraction of P.auriculata induced apoptosis and inhibited proliferation in colon cancer cells and could be used as a source for new lead structures in drug design to combat colon cancer.

Apoptosis induction in MV4-11 and K562 human leukemic cells by Pereskia sacharosa (Cactaceae) leaf crude extract.

PubMed

Asmaa, Mat Jusoh Siti; Al-Jamal, Hamid Ali Nagi; Ang, Cheng Yong; Asan, Jamaruddin Mat; Seeni, Azman; Johan, Muhammad Farid

2014-01-01

Pereskia sacharosa is a genus of cacti widely used in folk medicine for cancer-related treatment. Anti-proliferative effects have been studied in recent years against colon, breast, cervical and lung cancer cell lines, with promising results. We here extended study of anti-proliferative effects to a blood malignancy, leukemia. Two leukemic cell lines, MV4-11 (acute myeloid leukemia) and K562 (chronic myeloid leukemia), were studied. IC50 concentrations were determined and apoptosis and cell cycle regulation were studied by flow cytometric analysis. The expression of apoptosis and cell-cycle related regulatory proteins was assessed by Western blotting. P sacharosa inhibited growth of MV4-11 and K562 cells in a dose-dependent manner. The mode of cell death was via induction of intrinsic apoptotic pathways and cell cycle arrest. There was profound up-regulation of cytochrome c, caspases, p21 and p53 expression and repression of Akt and Bcl-2 expression in treated cells. These results suggest that P sacharosa induces leukemic cell death via apoptosis induction and changes in cell cycle checkpoint, thus deserves further study for anti-leukemic potential.

Ethylene is required for elicitin-induced oxidative burst but not for cell death induction in tobacco cell suspension cultures.

PubMed

Koehl, Julia; Djulic, Alma; Kirner, Veronika; Nguyen, Tach Thao; Heiser, Ingrid

2007-12-01

The signal compound ethylene and its relationships with oxidative burst and cell death were analyzed in cultured tobacco cells treated with the proteinaceous elicitor quercinin. Quercinin belongs to the protein family of elicitins and was isolated from the soil-born oak pathogen Phytophthora quercina. It was shown to induce a dose-dependent oxidative burst in tobacco cell culture in concentrations from 0.05 to 0.5 nM, and subsequently, cell death. The characteristics of quercinin-induced cell death included both membrane damage and DNA fragmentation in tobacco cell culture. At higher quercinin concentrations (2 nM), H(2)O(2) formation and ethylene biosynthesis were inhibited. Ethylene at low concentrations proved to be necessary for induction and maintenance of H(2)O(2) production in tobacco cells treated with quercinin. It was demonstrated that external addition of inhibitors of ethylene biosynthesis such as alpha-amino-oxy-acetic acid (AOA) and CoCl(2) also decreased or even inhibited the quercinin-induced oxidative burst, but did not influence cell death induction. These results demonstrate evidence for a requirement of the plant hormone ethylene for the onset of the quercinin-induced oxidative burst.

Beta-glycerophosphate accelerates RANKL-induced osteoclast formation in the presence of ascorbic acid.

PubMed

Noh, A Long Sae Mi; Yim, Mijung

2011-03-01

Despite numerous reports of the synergistic effects of beta-glycerophosphate and ascorbic acid in inducing the differentiation of osteoblasts, little is known about their roles in osteoclastic differentiation. Therefore, we investigated the effect of beta-glycerophosphate on osteoclastogenesis in the presence of ascorbic acid using primary mouse bone marrow cultures treated with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor (NF)-kappaB ligand (RANKL). Beta-Glycerophosphate dose-dependently increased RANKL-induced osteoclast formation in the presence of ascorbic acid. This stimulatory effect was apparent when beta-glycerophosphate and ascorbic acid were only added during the late stages of the culture period, indicating that they influence later events in osteoclastic differentiation. While the combination of beta-glycerophosphate and ascorbic acid inhibited RANKL-stimulated activation of ERK and p38, and degradation of IkappaB, it increased the induction of c-Fos and NFATc1. In addition, beta-glycerophosphate and ascorbic acid together enhanced the induction of COX-2 following RANKL stimulation. Taken together, our data suggest that beta-glycerophosphate and ascorbic acid have synergistic effects on osteoclast formation, increasing RANKL-mediated induction of c-Fos, NFATc1 and COX-2 in osteoclast precursors.

Induction of adaptive response in human blood lymphocytes exposed to radiofrequency radiation.

PubMed

Sannino, Anna; Sarti, Maurizio; Reddy, Siddharth B; Prihoda, Thomas J; Vijayalaxmi; Scarfì, Maria Rosaria

2009-06-01

The incidence of micronuclei was evaluated to assess the induction of an adaptive response to non-ionizing radiofrequency (RF) radiation in peripheral blood lymphocytes collected from five different human volunteers. After stimulation with phytohemagglutinin for 24 h, the cells were exposed to an adaptive dose of 900 MHz RF radiation used for mobile communications (at a peak specific absorption rate of 10 W/kg) for 20 h and then challenged with a single genotoxic dose of mitomycin C (100 ng/ml) at 48 h. Lymphocytes were collected at 72 h to examine the frequency of micronuclei in cytokinesis-blocked binucleated cells. Cells collected from four donors exhibited the induction of adaptive response (i.e., responders). Lymphocytes that were pre-exposed to 900 MHz RF radiation had a significantly decreased incidence of micronuclei induced by the challenge dose of mitomycin C compared to those that were not pre-exposed to 900 MHz RF radiation. These preliminary results suggested that the adaptive response can be induced in cells exposed to non-ionizing radiation. A similar phenomenon has been reported in cells as well as in animals exposed to ionizing radiation in several earlier studies. However, induction of adaptive response was not observed in the remaining donor (i.e., non-responder). The incidence of micronuclei induced by the challenge dose of mitomycin C was not significantly different between the cells that were pre-exposed and unexposed to 900 MHz RF radiation. Thus the overall data indicated the existence of heterogeneity in the induction of an adaptive response between individuals exposed to RF radiation and showed that the less time-consuming micronucleus assay can be used to determine whether an individual is a responder or non-responder.

Tandem High-Dose Chemotherapy and Autologous Stem Cell Transplantation for Atypical Teratoid/Rhabdoid Tumor

PubMed Central

Sung, Ki Woong; Lim, Do Hoon; Yi, Eun Sang; Choi, Young Bae; Lee, Ji Won; Yoo, Keon Hee; Koo, Hong Hoe; Kim, Ji Hye; Suh, Yeon-Lim; Joung, Yoo Sook; Shin, Hyung Jin

2016-01-01

Purpose We prospectively evaluated the effectiveness of tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) in improving the survival of patients with atypical teratoid/rhabdoid tumors while reducing the risks of late adverse effects from radiotherapy (RT). Materials and Methods For young children (< 3 years old), tandem HDCT/auto-SCT was administered after six cycles of induction chemotherapy. RT was deferred until after 3 years of age unless the tumor showed relapse or progression. For older patients (> 3 years old), RT including reduced-dose craniospinal RT (23.4 or 30.6 Gy) was administered either after two cycles of induction chemotherapy or after surgery, and tandem HDCT/auto-SCT was administered after six cycles of induction chemotherapy. Results A total of 13 patients (five young and eight older) were enrolled from November 2004 to June 2012. Eight patients, including all five young patients, had metastatic disease at diagnosis. Six patients (four young and two older) experienced progression before initiation of RT, and seven were able to proceed to HDCT/auto-SCT without progression during induction treatment. Three of six patients who experienced progression during induction treatment underwent HDCT/auto-SCT as salvage treatment. All five young patients died from disease progression. However, four of the eight older patients remain progression-freewith a median follow-up period of 64 months (range, 39 to 108 months). Treatment-related late toxicities were acceptable. Conclusion The required dose of craniospinal RT might be reduced in older patients if the intensity of chemotherapy is increased. However, early administration of RT should be considered to prevent early progression in young patients. PMID:27034140

A first-in-human pharmacodynamic and pharmacokinetic study of a fully human anti-glucagon receptor monoclonal antibody in normal healthy volunteers.

PubMed

Kostic, Ana; King, Thomas Alexander; Yang, Feng; Chan, Kuo-Chen; Yancopoulos, George D; Gromada, Jesper; Harp, Joyce B

2018-02-01

Glucagon receptor (GCGR) blockers are being investigated as potential therapeutics for type 1 and type 2 diabetes. Here we report the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of REGN1193, a fully human glucagon receptor blocking monoclonal antibody from a first-in-human healthy volunteer randomized double-blinded trial. Healthy men and women received single ascending doses of REGN1193 ranging from 0.05 to 0.6 mg/kg (n = 42) or placebo (n = 14) intravenously. Safety, tolerability and PK were assessed over 106 days. The glucose-lowering effect of REGN1193 was assessed after induction of hyperglycaemia by serial glucagon challenges. REGN1193 was generally well tolerated. There were small (<3× the upper limit of normal) and transient dose-dependent increases in hepatic aminotransferases. No increase in LDL-C was observed. Hypoglycaemia, assessed as laboratory blood glucose ≤70 mg/dL, occurred in 6/14 (43%) subjects on placebo and 27/42 (57%) on REGN1193 across all dose groups. All episodes of hypoglycaemia were asymptomatic, >50 mg/dL, and did not require treatment or medical assistance. Concentration-time profiles suggest a 2-compartment disposition and marked nonlinearity, consistent with target-mediated clearance. REGN1193 inhibited the glucagon-stimulated glucose increase in a dose-dependent manner. The 0.6 mg/kg dose inhibited the glucagon-induced glucose area under the curve for 0 to 90 minutes (AUC 0-90 minutes ) by 80% to 90% on days 3 and 15, while blunting the increase in C-peptide. REGN1193 dose-dependently increased total GLP-1, GLP-2 and glucagon, with plasma levels returning to baseline by day 29 in all dose groups. REGN1193, a GCGR-blocking monoclonal antibody, produced a safety, tolerability and PK/PD profile suitable for further clinical development. The occurrence of transient elevations in serum hepatic aminotransferases observed here and reported with several small molecule glucagon receptor antagonists suggests an on-target effect of glucagon receptor blockade. The underlying mechanism is unknown. © 2017 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

The efficacy of low dose azathioprine/6-mercaptopurine in patients with inflammatory bowel disease.

PubMed

Kim, Dong Uk; Kim, Young-Ho; Kim, Beom Jin; Chang, Dong Kyung; Son, Hee Jung; Rhee, Poong-Lyul; Kim, Jae J; Rhee, Jong Chul

2009-01-01

Azathioprine (AZA) and 6-mercaptopurine (6-MP) have been widely used in patients with ulcerative colitis (UC) and Crohn's disease (CD). However, some patients cannot tolerate standard doses (2-2.5 mg/kg for AZA or 1-1.5 mg/kg for 6-MP) due to side effects such as leukopenialneutropenia. The aim of this study was to evaluate the efficacy of low dose AZA/6-MP compared to the standard dose. From 1995 to 2005, 122 patients with UC or CD treated with AZA/6-MP at Samsung Medical Center in Korea were enrolled. We divided these patients into 2 groups (standard dose group versus low dose group) according to the maintenance dose. Among the 122 patients, 17 received the standard dose and 105 received a low dose. The mean maintenance doses were 2.25 mg/kg for the standard dose group and 1.35mg/kg for the low dose group. The clinical outcomes of remission induction, maintenance of remission and relapse rate showed no significant difference in comparisons between these two groups. Low dose AZA/6-MP was as effective as the standard dose for remission induction and maintenance of remission in patients with UC and CD. For patients that develop leukopenia/neutropenia during dose escalation, maintenance therapy with low dose AZA/6-MP should be considered.

Exposure to As-, Cd-, and Pb-mixture induces Aβ, amyloidogenic APP processing and cognitive impairments via oxidative stress-dependent neuroinflammation in young rats.

PubMed

Ashok, Anushruti; Rai, Nagendra Kumar; Tripathi, Sachin; Bandyopadhyay, Sanghamitra

2015-01-01

Environmental pollutants act as risk factors for Alzheimer's disease (AD), mainly affecting the aging population. We investigated early manifestations of AD-like pathology by a mixture of arsenic (As), cadmium (Cd), and lead (Pb), reported to impair neurodevelopment. We treated rats with As+Cd+Pb at their concentrations detected in groundwater of India, ie, 0.38, 0.098, and 0.22 ppm or 10 times of each, respectively, from gestation-05 to postnatal day-180. We identified dose-dependent increase in amyloid-beta (Aβ) in frontal cortex and hippocampus as early as post-weaning. The effect was strongly significant during early-adulthood, reaching levels comparable to an Aβ-infused AD-like rat model. The metals activated the proamyloidogenic pathway, mediated by increase in amyloid precursor protein (APP), and subsequent beta secretase (BACE) and presenilin (PS)-mediated APP-processing. Investigating the mechanism of Aβ-induction revealed an augmentation in oxidative stress-dependent neuroinflammation that stimulated APP expression through interleukin-responsive-APP-mRNA 5'-untranslated region. We then examined the effects of individual metals and binary mixtures in comparison with the tertiary. Among individual metals, Pb triggered maximum induction of Aβ, whereas individual As or Cd had a relatively non-significant effect on Aβ despite enhanced APP, owing to reduced induction of BACE and PS. Interestingly, when combined the metals demonstrated synergism, with a major contribution by As. The synergistic effect was significant and consistent in tertiary mixture, resulting in the augmentation of Aβ. Eventually, increase in Aβ culminated in cognitive impairments in the young rats. Together, our data demonstrate that exposure to As+Cd+Pb induces premature manifestation of AD-like pathology that is synergistic, and oxidative stress and inflammation dependent. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Xanthorrhizol, a natural sesquiterpenoid, induces apoptosis and growth arrest in HCT116 human colon cancer cells.

PubMed

Kang, You-Jin; Park, Kwang-Kyun; Chung, Won-Yoon; Hwang, Jae-Kwan; Lee, Sang Kook

2009-11-01

Xanthorrhizol is a sesquiterpenoid from the rhizome of Curcuma xanthorrhiza. In our previous studies, xanthorrhizol suppressed cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, inhibited cancer cell growth, and exerted an anti-metastatic effect in an animal model. However, the exact mechanisms for its inhibitory effects against cancer cell growth have not yet been fully elucidated. In the present study, we investigated the growth inhibitory effect of xanthorrhizol on cancer cells. Xanthorrhizol dose-dependently exerted antiproliferative effects against HCT116 human colon cancer cells. Xanthorrhizol also arrested cell cycle progression in the G0/G1 and G2/M phase and induced the increase of sub-G1 peaks. Cell cycle arrest was highly correlated with the downregulation of cyclin A, cyclin B1, and cyclin D1; cyclin-dependent kinase 1 (CDK1), CDK2, and CDK4; proliferating cell nuclear antigen; and inductions of p21 and p27, cyclin-dependent kinase inhibitors. The apoptosis by xanthorrhizol was markedly evidenced by induction of DNA fragmentation, release of cytochrome c, activation of caspases, and cleavage of poly-(ADP-ribose) polymerase. In addition, xanthorrhizol increased the expression and promoter activity of pro-apoptotic non-steroidal anti-inflammatory drug-activated gene-1 (NAG-1). These findings provide one plausible mechanism for the growth inhibitory activity of xanthorrhizol against cancer cells.

Dextran loading protects macrophages from lipid peroxidation and induces a Keap1/Nrf2/ARE-dependent antioxidant response.

PubMed

Chechushkov, Anton; Zaitseva, Natalia; Vorontsova, Elena; Kozhin, Petr; Menshchikova, Elena; Shkurupiy, Vyacheslav

2016-12-01

Linear dextrans are often proposed as drug delivery systems with milder adverse effects and lower effective drug concentrations. Linear dextrans are polysaccharides that can potentially be used to load macrophages with drugs to transport them to a site of inflammation. Recently, it was reported that dextrans may exert a protective effect vis-à-vis drug cytotoxicity and during wound healing. The aim of the current work was to evaluate molecular mechanisms of action of dextrans that may be relevant to the cytoprotective effects. We determined the effect of treatment with 40- or 70-kDa dextran on production of reactive oxygen species, lipid peroxidation, and lysosomal pH in the J774 macrophage cell line. In addition, induction of Keap1/Nrf2/ARE and autophagic activity were evaluated. Dextrans of both molecular weights protected the cells from oxidative stress induced by cumene hydroperoxide and from lysosomal stress induced by ammonium chloride. The effect was associated with induction of the Keap1/Nrf2/ARE signaling pathway. Furthermore, dextran stimulated autophagy in a dose-dependent manner but inhibited the autophagosome-lysosome fusion in a time-dependent manner. This study shows possible cytoprotective effects of dextran under oxidative stress, and these findings may be used for the development of novel (dextran-based) drug delivery approaches. Copyright © 2016 Elsevier Inc. All rights reserved.

Dexamethasone Enhances 1α,25-Dihydroxyvitamin D3 Effects by Increasing Vitamin D Receptor Transcription*

PubMed Central

Hidalgo, Alejandro A.; Deeb, Kristin K.; Pike, J. Wesley; Johnson, Candace S.; Trump, Donald L.

2011-01-01

Calcitriol, the active form of vitamin D, in combination with the glucocorticoid dexamethasone (Dex) has been shown to increase the antitumor effects of calcitriol in squamous cell carcinoma. In this study we found that pretreatment with Dex potentiates calcitriol effects by inhibiting cell growth and increasing vitamin D receptor (VDR) and VDR-mediated transcription. Treatment with actinomycin D inhibits Vdr mRNA synthesis, indicating that Dex regulates VDR expression at transcriptional level. Real time PCR shows that treatment with Dex increases Vdr transcripts in a time- and a dose-dependent manner, indicating that Dex directly regulates expression of Vdr. RU486, an inhibitor of glucocorticoids, inhibits Dex-induced Vdr expression. In addition, the silencing of glucocorticoid receptor (GR) abolishes the induction of Vdr by Dex, indicating that Dex increases Vdr transcripts in a GR-dependent manner. A fragment located 5.2 kb upstream of Vdr transcription start site containing two putative glucocorticoid response elements (GREs) was evaluated using a luciferase-based reporter assay. Treatment with 100 nm Dex induces transcription of luciferase driven by the fragment. Deletion of the GRE distal to transcription start site was sufficient to abolish Dex induction of luciferase. Also, chromatin immunoprecipitation reveals recruitment of GR to distal GRE with Dex treatment. We conclude that Dex increases VDR and vitamin D effects by increasing Vdr de novo transcription in a GR-dependent manner. PMID:21868377

PKI 166 induced redox signalling and apoptosis through activation of p53, MAP kinase and caspase pathway in epidermoid carcinoma.

PubMed

Das, Subhasis; Dey, Kaushik Kumar; Bharti, Rashmi; MaitiChoudhury, Sujata; Maiti, Sukumar; Mandal, Mahitosh

2012-01-01

Cellular redox changes have emerged as a pivotal and proximal event in cancer. PKI 166 is used to determine the effects of redox sensitive inhibition of EGFR, metastasis and apoptosis in epidermoid carcinoma. Cytotoxicity study of PKI 166 (IC50 1.0 microM) treated A431 cells were performed by MTT assay for 48 and 72 hrs. Morphological analysis of PKI 166 treated A431 cells for 48 hrs. revealed the cell shrinkage, loss of filopodia and lamellipodia by phase contrast and SEM images in dose dependent manner. It has cytotoxic effects through inhibiting cellular proliferation, leads to the induction of apoptosis, as increased fraction of sub-G1 phase of the cell cycle, chromatin condensation and DNA ladder. It inhibited cyclin-D1 and cyclin-E expression and induced p53, p21 expression in dose dependent manner. Consequently, an imbalance of Bax/Bcl-2 ratio triggered caspase cascade and subsequent cleavage of PARP, thereby shifting the balance in favour of apoptosis. PKI 166 treatment actively stimulated reactive oxygen species (ROS) and mitochondrial membrane depolarization. It inhibited some metastatic properties of A431 cells supressing colony formation by soft agar assay and inhibition of MMP 9 activity by gelatin zymography and western blot analysis. PKI 166 inhibited growth factor induced phosphorylation of EGFR, Akt, MAPK, JNK and colony formation in A431 cells. Thus the inhibition of proliferation was associated with redox regulation of the caspase cascade, EGFR, Akt/PI3K, MAPK/ ERK and JNK pathway. On the other hand, increased antioxidant activity leads to decreased ROS generation inhibit the anti-proliferative and apoptotic properties of PKI 166 in A431 cells. These observations indicated PKI 166 induced redox signalling dependent inhibition of cell proliferation, metastatic properties and induction of apoptotic potential in epidermoid carcinoma.

Differential response of nNOS knockout mice to MDMA ("ecstasy")- and methamphetamine-induced psychomotor sensitization and neurotoxicity.

PubMed

Itzhak, Yossef; Anderson, Karen L; Ali, Syed F

2004-10-01

It has been shown that mice deficient in neuronal nitric oxide synthase (nNOS) gene are resistant to cocaine-induced psychomotor sensitization and methamphetamine (METH)-induced dopaminergic neurotoxicity. The present study was undertaken to investigate the hypothesis that nNOS has a major role in dopamine (DA)- but not serotonin (5-hydroxytryptamine; 5-HT)-mediated effects of psychostimulants. The response of nNOS knockout (KO) and wild-type (WT) mice to the psychomotor-stimulating and neurotoxic effects of 3,4-methylenedioxymethamphetamine (MDMA; "Ecstasy") and METH were investigated. Repeated administration of MDMA for 5 days resulted in psychomotor sensitization in both WT and nNOS KO mice, while repeated administration of METH caused psychomotor sensitization in WT but not in KO mice. Sensitization to both MDMA and METH was persistent for 40 days in WT mice, but not in nNOS KO mice. These findings suggest that the induction of psychomotor sensitization to MDMA and METH is NO independent and NO dependent, respectively, while the persistence of sensitization to both drugs is NO dependent. For the neurochemical studies, a high dose of MDMA caused marked depletion of 5-HT in several brain regions of both WT and KO mice, suggesting that the absence of the nNOS gene did not afford protection against MDMA-induced depletion of 5-HT. Striatal dopaminergic neurotoxicity caused by high doses of MDMA and METH in WT mice was partially prevented in KO mice administered with MDMA, but it was fully precluded in KO mice administered with METH. The differential response of nNOS KO mice to the behavioral and neurotoxic effects of MDMA and METH suggests that the nNOS gene is required for the expression and persistence of DA-mediated effects of METH and MDMA, while 5-HT-mediated effects of MDMA (induction of sensitization and 5-HT depletion) are not dependent on nNOS.

Fluoride induces endoplasmic reticulum stress and inhibits protein synthesis and secretion.

PubMed

Sharma, Ramaswamy; Tsuchiya, Masahiro; Bartlett, John D

2008-09-01

Exposure to excessive amounts of fluoride (F(-)) causes dental fluorosis in susceptible individuals; however, the mechanism of F(-)-induced toxicity is unclear. Previously, we have shown that high-dose F(-) activates the unfolded protein response (UPR) in ameloblasts that are responsible for dental enamel formation. The UPR is a signaling pathway responsible for either alleviating endoplasmic reticulum (ER) stress or for inducing apoptosis of the stressed cells. In this study we determined if low-dose F(-) causes ER stress and activates the UPR, and we also determined whether F(-) interferes with the secretion of proteins from the ER. We stably transfected the ameloblast-derived LS8 cell line with secreted alkaline phosphatase (SEAP) and determined activity and localization of SEAP and F(-)-mediated induction of UPR proteins. Also, incisors from mice given drinking water containing various concentrations of F(-) were examined for eucaryotic initiation factor-2, subunit alpha (eIF2alpha) phosphorylation. We found that F(-) decreases the extracellular secretion of SEAP in a linear, dose-dependent manner. We also found a corresponding increase in the intracellular accumulation of SEAP after exposure to F(-). These changes are associated with the induction of UPR proteins such as the molecular chaperone BiP and phosphorylation of the UPR sensor PKR-like ER kinase, and its substrate, eIF2alpha. Importantly, F(-)-induced phosphorylation of eIF2alphawas confirmed in vivo. These data suggest that F(-) initiates an ER stress response in ameloblasts that interferes with protein synthesis and secretion. Consequently, ameloblast function during enamel development may be impaired, and this may culminate in dental fluorosis.

The targeted histone deacetylase inhibitor tefinostat (CHR-2845) shows selective in vitro efficacy in monocytoid-lineage leukaemias

PubMed Central

Zabkiewicz, Joanna; Gilmour, Marie; Hills, Robert; Vyas, Pares; Bone, Elizabeth; Davidson, Alan; Burnett, Alan; Knapper, Steven

2016-01-01

Tefinostat (CHR-2845) is a novel monocyte/macrophage-targeted histone deacetylase (HDAC) inhibitor which is cleaved into its active acid by the intracellular esterase human carboxylesterase-1 (hCE-1). The in vitro efficacy of tefinostat was characterised in cell lines and in a cohort of 73 primary AML and CMML samples. Dose-dependent induction of apoptosis and significant growth inhibitory effects were seen in myelomonocytic (M4), monocytic/monoblastic (M5) and CMML samples in comparison to non-monocytoid AML sub-types (p = 0.007). Importantly, no growth inhibitory effects were seen in normal bone marrow CD34+ cells exposed to AML-toxic doses of tefinostat in clonogenic assays. Expression of hCE-1 was measured by intracellular flow cytometry and immunoblotting across the cohort, with highest levels seen in M5 AML patients. hCE-1 levels correlated with significantly increased tefinostat sensitivity (low EC50) as measured by growth inhibition assays (p = 0.001) and concomitant elevation of the mature monocytoid marker CD14+. Strong induction of intracellular histone protein acetylation was observed in tefinostat-responsive samples, as were high levels of the DNA damage sensor γ-H2A.X, highlighting potential biomarkers of patient responsiveness. Synergistic interaction between tefinostat and the current standard treatment cytarabine was demonstrated in dose response and clonogenic assays using simultaneous drug addition in primary samples (median Combination Index value = 0.51). These data provide a strong rationale for the further clinical evaluation of tefinostat in monocytoid-lineage haematological neoplasms including CMML and monocyte-lineage AMLs. PMID:26934551

Radiation-Induced Salivary Gland Dysfunction Results From p53-Dependent Apoptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Avila, Jennifer L.; Grundmann, Oliver; Burd, Randy

2009-02-01

Purpose: Radiotherapy for head-and-neck cancer causes adverse secondary side effects in the salivary glands and results in diminished quality of life for the patient. A previous in vivo study in parotid salivary glands demonstrated that targeted head-and-neck irradiation resulted in marked increases in phosphorylated p53 (serine{sup 18}) and apoptosis, which was suppressed in transgenic mice expressing a constitutively active mutant of Akt1 (myr-Akt1). Methods and Materials: Transgenic and knockout mouse models were exposed to irradiation, and p53-mediated transcription, apoptosis, and salivary gland dysfunction were analyzed. Results: The proapoptotic p53 target genes PUMA and Bax were induced in parotid salivary glandsmore » of mice at early time points after therapeutic radiation. This dose-dependent induction requires expression of p53 because no radiation-induced expression of PUMA and Bax was observed in p53-/- mice. Radiation also induced apoptosis in the parotid gland in a dose-dependent manner, which was p53 dependent. Furthermore, expression of p53 was required for the acute and chronic loss of salivary function after irradiation. In contrast, apoptosis was not induced in p53-/- mice, and their salivary function was preserved after radiation exposure. Conclusions: Apoptosis in the salivary glands after therapeutic head-and-neck irradiation is mediated by p53 and corresponds to salivary gland dysfunction in vivo.« less

Thrombocytopenia induced by the histone deacetylase inhibitor abexinostat involves p53-dependent and -independent mechanisms.

PubMed

Ali, A; Bluteau, O; Messaoudi, K; Palazzo, A; Boukour, S; Lordier, L; Lecluse, Y; Rameau, P; Kraus-Berthier, L; Jacquet-Bescond, A; Lelièvre, H; Depil, S; Dessen, P; Solary, E; Raslova, H; Vainchenker, W; Plo, I; Debili, N

2013-07-25

Abexinostat is a pan histone deacetylase inhibitor (HDACi) that demonstrates efficacy in malignancy treatment. Like other HDACi, this drug induces a profound thrombocytopenia whose mechanism is only partially understood. We have analyzed its effect at doses reached in patient plasma on in vitro megakaryopoiesis derived from human CD34(+) cells. When added at day 0 in culture, abexinostat inhibited CFU-MK growth, megakaryocyte (MK) proliferation and differentiation. These effects required only a short incubation period. Decreased proliferation was due to induction of apoptosis and was not related to a defect in TPO/MPL/JAK2/STAT signaling. When added later (day 8), the compound induced a dose-dependent decrease (up to 10-fold) in proplatelet (PPT) formation. Gene profiling from MK revealed a silencing in the expression of DNA repair genes with a marked RAD51 decrease at protein level. DNA double-strand breaks were increased as attested by elevated γH2AX phosphorylation level. Moreover, ATM was phosphorylated leading to p53 stabilization and increased BAX and p21 expression. The use of a p53 shRNA rescued apoptosis, and only partially the defect in PPT formation. These results suggest that HDACi induces a thrombocytopenia by a p53-dependent mechanism along MK differentiation and a p53-dependent and -independent mechanism for PPT formation.

No clinically relevant CYP3A induction after St. John's wort with low hyperforin content in healthy volunteers.

PubMed

Mueller, Silke C; Majcher-Peszynska, Jolanta; Mundkowski, Ralf G; Uehleke, Bernhard; Klammt, Sebastian; Sievers, Hartwig; Lehnfeld, Romanus; Frank, Bruno; Thurow, Kerstin; Kundt, Guenther; Drewelow, Bernd

2009-01-01

Induction of CYP3A by St. John's wort (SJW) products with high hyperforin content is well described. Since CYP3A induction is mediated by hyperforin in a concentration-dependent manner, and SJW preparations differ significantly in hyperforin content, the aim of the study was to evaluate the effect of an SJW powder with low hyperforin content on CYP3A function. Twenty healthy male volunteers received an SJW powder with low hyperforin content for 2 weeks. Midazolam plasma concentration time profiles were characterized after a single oral dose of 7.5 mg midazolam on the day before and on the 14th day of SJW medication. Midazolam AUC(0-infinity) slightly decreased from 124.0 +/- 62.5 ng/ml.h at baseline to 105.6 +/- 53.2 ng/ml.h after SJW (P < 0.05), representing a mean 11.3% decrease (95% CI: -22.8 to 0.21). No significant change in midazolam C(max), t(1/2) and t(max) was observed. For all pharmacokinetic parameters, the 90% CI for the geometric mean ratio of treatment over baseline were within the no-effect boundaries of 0.70-1.43. Administration of an SJW product with low hyperforin content resulted in a mild induction of CYP3A not considered clinically relevant.

Intermediate-dose cytarabine plus mitoxantrone versus standard-dose cytarabine plus daunorubicin for acute myeloid leukemia in elderly patients.

PubMed

Röllig, C; Kramer, M; Gabrecht, M; Hänel, M; Herbst, R; Kaiser, U; Schmitz, N; Kullmer, J; Fetscher, S; Link, H; Mantovani-Löffler, L; Krümpelmann, U; Neuhaus, T; Heits, F; Einsele, H; Ritter, B; Bornhäuser, M; Schetelig, J; Thiede, C; Mohr, B; Schaich, M; Platzbecker, U; Schäfer-Eckart, K; Krämer, A; Berdel, W E; Serve, H; Ehninger, G; Schuler, U S

2018-04-01

The combination of intermediate-dose cytarabine plus mitoxantrone (IMA) can induce high complete remission rates with acceptable toxicity in elderly patients with acute myeloid leukemia (AML). We present the final results of a randomized-controlled trial comparing IMA with the standard 7 + 3 induction regimen consisting of continuous infusion cytarabine plus daunorubicin (DA). Patients with newly diagnosed AML >60 years were randomized to receive either intermediate-dose cytarabine (1000 mg/m2 twice daily on days 1, 3, 5, 7) plus mitoxantrone (10 mg/m2 days 1-3) (IMA) or standard induction therapy with cytarabine (100 mg/m2 continuously days 1-7) plus daunorubicin (45 mg/m2 days 3-5) (DA). Patients in complete remission after DA received intermediate-dose cytarabine plus amsacrine as consolidation treatment, whereas patients after IMA were consolidated with standard-dose cytarabine plus mitoxantrone. Between February 2005 and October 2009, 485 patients were randomized; 241 for treatment arm DA and 244 for IMA; 76% of patients were >65 years. The complete response rate after DA was 39% [95% confidence interval (95% CI): 33-45] versus 55% (95% CI: 49-61) after IMA (odds ratio 1.89, P = 0.001). The 6-week early-death rate was 14% in both arms. Relapse-free survival curves were superimposable in the first year, but separated afterwards, resulting in 3-year relapse-free survival rates of 29% versus 14% in the DA versus IMA arms, respectively (P = 0.042). The median overall survival was 10 months in both arms (P = 0.513). The dose escalation of cytarabine in induction therapy lead to improved remission rates in the elderly AML patients. This did not translate into a survival advantage, most likely due to differences in consolidation treatment. Thus, effective consolidation strategies need to be further explored. In combination with an effective consolidation strategy, the use of intermediate-dose cytarabine in induction may improve curative treatment for elderly AML patients.

Physics must join with biology in better assessing risk from low-dose irradiation.

PubMed

Feinendegen, L E; Neumann, R D

2005-01-01

This review summarises the complex response of mammalian cells and tissues to low doses of ionising radiation. This thesis encompasses induction of DNA damage, and adaptive protection against both renewed damage and against propagation of damage from the basic level of biological organisation to the clinical expression of detriment. The induction of DNA damage at low radiation doses apparently is proportional to absorbed dose at the physical/chemical level. However, any propagation of such damage to higher levels of biological organisation inherently follows a sigmoid function. Moreover, low-dose-induced inhibition of damage propagation is not linear, but instead follows a dose-effect function typical for adaptive protection, after an initial rapid rise it disappears at doses higher than approximately 0.1-0.2 Gy to cells. The particular biological response duality at low radiation doses precludes the validity of the linear-no-threshold hypothesis in the attempt to relate absorbed dose to cancer. In fact, theory and observation support not only a lower cancer incidence than expected from the linear-no-threshold hypothesis, but also a reduction of spontaneously occurring cancer, a hormetic response, in the healthy individual.

A redox-based mechanism for induction of interleukin-1 production by nitric oxide in a human colonic epithelial cell line (HT29-Cl.16E).

PubMed Central

Vallette, G; Jarry, A; Branka, J E; Laboisse, C L

1996-01-01

We evaluated the effects of two NO donors, sodium nitroprusside (SNP) and 3-morpholino-sydnonimine (SIN-1), characterized by alternative redox states, i.e. nitrosonium ion (NO+) and nitric oxide (NO.) respectively, on intracellular interleukin-1 (IL-1) production, by a human colonic epithelial cell line (HT29-Cl.16E). SNP was able to induce intracellular IL-1 alpha production up to 10 h incubation, in a dose-dependent manner. Several experiments provide evidence that the NO+ redox form, and not the free radical NO., is implicated in the IL-1 alpha production: (i) SIN-1, devoid of any NO+ character, led to a very weak IL-1 production as compared with SNP; (ii) the reductive action of a thiol such as cysteine on NO+ led to a dose-dependent increase in NO, concentration, measured as NO2-/NO3- accumulation, and to large decrease in IL-1 production. Dibutyryl cGMP had no effect on IL-1 production, this finding supporting the concept that a cGMP-independent pathway is involved in the intracellular signalling of NO+. Together these results point out that NO, depending on its redox form, is able to modulate IL-1 production in cultured colonic epithelial cells. PMID:8546706

A redox-based mechanism for induction of interleukin-1 production by nitric oxide in a human colonic epithelial cell line (HT29-Cl.16E).

PubMed

Vallette, G; Jarry, A; Branka, J E; Laboisse, C L

1996-01-01

We evaluated the effects of two NO donors, sodium nitroprusside (SNP) and 3-morpholino-sydnonimine (SIN-1), characterized by alternative redox states, i.e. nitrosonium ion (NO+) and nitric oxide (NO.) respectively, on intracellular interleukin-1 (IL-1) production, by a human colonic epithelial cell line (HT29-Cl.16E). SNP was able to induce intracellular IL-1 alpha production up to 10 h incubation, in a dose-dependent manner. Several experiments provide evidence that the NO+ redox form, and not the free radical NO., is implicated in the IL-1 alpha production: (i) SIN-1, devoid of any NO+ character, led to a very weak IL-1 production as compared with SNP; (ii) the reductive action of a thiol such as cysteine on NO+ led to a dose-dependent increase in NO, concentration, measured as NO2-/NO3- accumulation, and to large decrease in IL-1 production. Dibutyryl cGMP had no effect on IL-1 production, this finding supporting the concept that a cGMP-independent pathway is involved in the intracellular signalling of NO+. Together these results point out that NO, depending on its redox form, is able to modulate IL-1 production in cultured colonic epithelial cells.

Adaptogenic and nootropic activities of aqueous extract of Vitis vinifera (grape seed): an experimental study in rat model

PubMed Central

Sreemantula, Satyanarayana; Nammi, Srinivas; Kolanukonda, Rajabhanu; Koppula, Sushruta; Boini, Krishna M

2005-01-01

Background The aerial parts of Vitis vinifera (common grape or European grape) have been widely used in Ayurveda to treat a variety of common and stress related disorders. In the present investigation, the seed extract of V. vinifera was evaluated for antistress activity in normal and stress induced rats. Furthermore, the extract was studied for nootropic activity in rats and in-vitro antioxidant potential to correlate its antistress activity. Methods For the evaluation of antistress activity, groups of rats (n = 6) were subjected to forced swim stress one hour after daily treatment of V. vinifera extract. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as non-invasive biomarkers to assess the antistress activity. The 24 h urinary excretion of vanillylmandelic acid (VMA) and ascorbic acid were determined by spectrophotometric methods in all groups under normal and stressed conditions. The nootropic activity of the extract as determined from acquisition, retention and retrieval in rats was studied by conditioned avoidance response using Cook's pole climbing apparatus. The in vitro antioxidant activity was determined based on the ability of V. vinifera to scavenge hydroxyl radicals. Results Daily administration of V. vinifera at doses of 100, 200 and 300 mg/kg body weight one hour prior to induction of stress inhibited the stress induced urinary biochemical changes in a dose dependent manner. However, no change in the urinary excretion of VMA and ascorbic acid was observed in normal animals at all the doses studied. The cognition, as determined by the acquisition, retention and recovery in rats was observed to be dose dependent. The extract also produced significant inhibition of hydroxyl radicals in comparison to ascorbic acid in a dose dependent manner. Conclusion The present study provides scientific support for the antistress (adaptogenic), antioxidant and nootropic activities of V. vinifera seed extract and substantiate the traditional claims for the usage of grape fruits and seeds in stress induced disorders. PMID:15656916

Curcumin induced autophagy anticancer effects on human lung adenocarcinoma cell line A549

PubMed Central

Liu, Furong; Gao, Song; Yang, Yuxuan; Zhao, Xiaodan; Fan, Yameng; Ma, Wenxia; Yang, Danrong; Yang, Aimin; Yu, Yan

2017-01-01

To investigate the anticancer effects of curcumin-induced autophagy and its effects on the human lung adenocarcinoma A549 cell line, inverted phase contrast microscopy was used to observe alterations to the cytomorphology of cells. An MTT assay was used to measure cell viability. Autophagy was detected using acridine orange (AO) staining and 3-methyladenine (3-MA) was used as an autophagy-specific inhibitor. Dose- and time-dependent A549 cell viability inhibition was observed following curcumin treatment. A dose-dependent increase in the red fluorescent structures in A549 cells was identified following curcumin treatment for 48 h through AO staining. In addition, the activation of autophagy was determined through changes in the number of autophagic vesicles (AVs; fluorescent particles) infected with monodansylcadaverine (MDC). The fluorescence intensity and density of AVs in the curcumin-treated groups were higher at 48 h compared with the control group. Finally, the MTT assay demonstrated that the survival rates of the curcumin-treated cells were increased when pretreated with 3-MA for 3 h, indicating that the inhibitory effect of curcumin on A549 cells is reduced following the inhibition of autophagy. Furthermore, AO and MDC staining confirmed that 3-MA does inhibit the induction of autophagy. Thus, it was hypothesized that the induction of autophagy is partially involved in the reduction of cell viability observed following curcumin treatment. The anticancer effects of curcumin on A549 cells can be reduced using autophagy inhibitors. This suggests a possible cancer therapeutic application of curcumin through the activation of autophagy. These findings have improved the understanding of the mechanism underlying the anticancer property of curcumin. PMID:28928819

Advanced Glycation End-Products Induce Apoptosis in Pancreatic Islet Endothelial Cells via NF-κB-Activated Cyclooxygenase-2/Prostaglandin E2 Up-Regulation

PubMed Central

Lan, Kuo-Cheng; Chiu, Chen-Yuan; Kao, Chia-Wei; Huang, Kuo-How; Wang, Ching-Chia; Huang, Kuo-Tong; Tsai, Keh-Sung

2015-01-01

Microvascular complications eventually affect nearly all patients with diabetes. Advanced glycation end-products (AGEs) resulting from hyperglycemia are a complex and heterogeneous group of compounds that accumulate in the plasma and tissues in diabetic patients. They are responsible for both endothelial dysfunction and diabetic vasculopathy. The aim of this study was to investigate the cytotoxicity of AGEs on pancreatic islet microvascular endothelial cells. The mechanism underlying the apoptotic effect of AGEs in pancreatic islet endothelial cell line MS1 was explored. The results showed that AGEs significantly decreased MS1 cell viability and induced MS1 cell apoptosis in a dose-dependent manner. AGEs dose-dependently increased the expressions of cleaved caspase-3, and cleaved poly (ADP-ribose) polymerase in MS1 cells. Treatment of MS1 cells with AGEs also resulted in increased nuclear factor (NF)-κB-p65 phosphorylation and cyclooxygenase (COX)-2 expression. However, AGEs did not affect the expressions of endoplasmic reticulum (ER) stress-related molecules in MS1 cells. Pretreatment with NS398 (a COX-2 inhibitor) to inhibit prostaglandin E2 (PGE2) production reversed the induction of cleaved caspase-3, cleaved PARP, and MS1 cell viability. Moreover, AGEs significantly increased the receptor for AGEs (RAGE) protein expression in MS1 cells, which could be reversed by RAGE neutralizing antibody. RAGE Neutralizing antibody could also reverse the induction of cleaved caspase-3 and cleaved PARP and decreased cell viability induced by AGEs. These results implicate the involvement of NF-κB-activated COX-2/PGE2 up-regulation in AGEs/RAGE-induced islet endothelial cell apoptosis and cytotoxicity. These findings may provide insight into the pathological processes within the pancreatic islet microvasculature induced by AGEs accumulation. PMID:25898207

Genotoxicity evaluation of carbon monoxide and 1, 3-butadiene using a new joint technology - the in vitro γH2AX HCS assay combined with air-liquid interface system.

PubMed

Zhang, Sen; Chen, Huan; Wang, An; Liu, Yong; Hou, Hongwei; Hu, Qingyuan

2018-05-21

To investigate the genotoxicity of gaseous toxicants CO and 1,3-butadiene in vitro, a novel combination technology-the in vitro γH2AX high content screening assay combined with air-liquid interface system was established. The results showed that this new technology was available and effective. Based on the joint technology, genotoxicity of CO and 1,3-butadiene was evaluated further in this study. The results showed that treatment concentrations (0, 20%,40%, 80% and 100%, v/v) and exposure time (15, 30, 45, 60 and 90 min) of CO both had no statistically significant effects on the induction of γH2AX (p > 0.05). However, 1,3-butadiene can induce significant γH2AX (p < 0.01) in A549 cells in a dose/time-dependent manner both in the absence and presence of rat liver S9. When the concentrations of 1,3-butadiene were more than 80%, a higher γH2AX level could be induced than the 1.5-fold of vehicle controls after 1 h of treatment. Overall, this new technology can be used a complementary tool to evaluate the genotoxicity of airborne toxicants in vitro based on the in vitro γH2AX high content screening assay combined with air-liquid interface system. Based on the joint technology, CO was not genotoxic in A549 cells, while 1,3-butadiene showed significant genotoxicity in the dose/time-dependency on the induction of γH2AX.

Evaluation of n-hexane extract of Viola betonicifolia for its neuropharmacological properties.

PubMed

Muhammad, Naveed; Saeed, Muhammad; Khan, Haroon; Haq, Ikramul

2013-01-01

Viola betonicifolia (whole plant) has been used as a sedative and in various nervous disorders in Pakistani traditional medicines. The n-hexane extract of the whole plant of V. betonicifolia (HEVB) was investigated for neuropharmacological properties such as anxiolytic, muscle relaxant, sleep induction, antidepressant and sedative to ascertain its folk use. Anxiolytic activity was tested using the staircase test, while the muscle relaxing property of the extract was tested in various muscle relaxant paradigms, i.e. chimney test, traction test, rota rod and inclined plane. In anxiolytic and muscle relaxant tests, HEVB (0.3, 0.4 and 0.5 g/kg, i.p.), diazepam (1 mg/kg, i.p.) or distilled water (10 ml/kg i.p.) were administered 30, 60 and 90 min before performing the tests in mice. HEVB was also screened for a sleep-inducing effect. The antidepressant activity was determined by using the forced swimming test (FST), while line crossing in a special box was used for locomotor activity. HEVB showed a significant (P < 0.05) dose-dependent anxiolytic action in the staircase test. In muscle relaxant paradigms, a dose-dependent muscle relaxation was observed. For the phenobarbitone sleep induction test, HEVB notably (P < 0.05) reduced the latency time and increased the total sleeping duration. However, HEVB was devoid of any antidepressant activity, while the movements of mice were reduced significantly (P < 0.05) in locomotor activity. The results suggest that HEVB has anxiolytic, muscle relaxant, sleep-inducing (sedative) activity and, thus, provides pharmacological justification for the use of this plant as a sedative and for the relief of various nervous disorders.

Curcumin induced autophagy anticancer effects on human lung adenocarcinoma cell line A549.

PubMed

Liu, Furong; Gao, Song; Yang, Yuxuan; Zhao, Xiaodan; Fan, Yameng; Ma, Wenxia; Yang, Danrong; Yang, Aimin; Yu, Yan

2017-09-01

To investigate the anticancer effects of curcumin-induced autophagy and its effects on the human lung adenocarcinoma A549 cell line, inverted phase contrast microscopy was used to observe alterations to the cytomorphology of cells. An MTT assay was used to measure cell viability. Autophagy was detected using acridine orange (AO) staining and 3-methyladenine (3-MA) was used as an autophagy-specific inhibitor. Dose- and time-dependent A549 cell viability inhibition was observed following curcumin treatment. A dose-dependent increase in the red fluorescent structures in A549 cells was identified following curcumin treatment for 48 h through AO staining. In addition, the activation of autophagy was determined through changes in the number of autophagic vesicles (AVs; fluorescent particles) infected with monodansylcadaverine (MDC). The fluorescence intensity and density of AVs in the curcumin-treated groups were higher at 48 h compared with the control group. Finally, the MTT assay demonstrated that the survival rates of the curcumin-treated cells were increased when pretreated with 3-MA for 3 h, indicating that the inhibitory effect of curcumin on A549 cells is reduced following the inhibition of autophagy. Furthermore, AO and MDC staining confirmed that 3-MA does inhibit the induction of autophagy. Thus, it was hypothesized that the induction of autophagy is partially involved in the reduction of cell viability observed following curcumin treatment. The anticancer effects of curcumin on A549 cells can be reduced using autophagy inhibitors. This suggests a possible cancer therapeutic application of curcumin through the activation of autophagy. These findings have improved the understanding of the mechanism underlying the anticancer property of curcumin.

Pressure-dependent changes in haematocrit and plasma volume during anaesthesia, a randomised clinical trial.

PubMed

Damén, T; Reinsfelt, B; Redfors, B; Nygren, A

2016-05-01

Induction of general anaesthesia has been shown to cause haemodilution and an increase in plasma volume. The aim of this study was to evaluate whether prevention of hypotension during anaesthesia induction could avoid haemodilution. Twenty-four cardiac surgery patients, 66 ± 10 years, were randomised to receive either norepinephrine in a dose needed to maintain mean arterial blood pressure (MAP) at pre-anaesthesia levels after induction or to a control group that received vasopressor if MAP decreased below 60 mmHg. No fluids were infused. Changes in plasma volume were calculated with standard formula: 100 × (Hct(pre)/Hct(post) - 1)/(1 - Hct(pre)). Arterial blood gas was analysed every 10 minutes and non-invasive continuous haemoglobin (SpHb) was continuously measured. Pre-anaesthesia MAP was 98 ± 7 mmHg. Ten minutes after anaesthesia induction, the haematocrit decreased by 5.0 ± 2.5% in the control group compared with 1.2 ± 1.4% in the intervention group, which corresponds to increases in plasma volume by 310 ml and 85 ml respectively. MAP decreased to 69 ± 15 mmHg compared to 92 ± 10 mmHg in the intervention group. The difference maintained throughout the 70 min intervention period. The change in haemoglobin level measured by blood gas analysis could not be detected by SpHb measurement. The mean bias between the SpHb and blood gas haemoglobin was 15 g/l. During anaesthesia induction, haematocrit decreases and plasma volume increases early and parallel to a decrease in blood pressure. This autotransfusion is blunted when blood pressure is maintained at pre-induction levels with norepinephrine. © 2016 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Dexamethasone inhibits high glucose-, TNF-alpha-, and IL-1beta-induced secretion of inflammatory and angiogenic mediators from retinal microvascular pericytes.

PubMed

Nehmé, Alissar; Edelman, Jeffrey

2008-05-01

To characterize the effects of dexamethasone in human retinal pericytes (HRMPs), monocytes (THP-1), and retinal endothelial cells (HRECs) treated with high glucose, TNF-alpha, or IL-1beta. HRMP and HREC phenotypes were verified by growth factor stimulation of intracellular calcium-ion mobilization. Glucocorticoid receptor phosphorylation was assessed with an anti-phospho-Ser(211) glucocorticoid receptor antibody. Secretion of 89 inflammatory and angiogenic proteins were compared in cells incubated with (1) normal (5 mM) or high (25 mM) D-glucose and (2) control medium, TNF-alpha (10 ng/mL), or IL-1beta (10 ng/mL), with or without dexamethasone (1 nM to 1 microM). The proteins were compared by using multianalyte profile testing. HRMPs and HRECs expressed functional PDGFB-R and VEGFR-2, respectively. Dexamethasone induction of glucocorticoid receptor phosphorylation was dose-dependent in all cell types. High glucose increased secretion of inflammatory mediators in HRMPs, but not in HRECs. Dexamethasone dose dependently inhibited secretion of these mediators in HRMPs. For all cells, TNF-alpha and IL-1beta induced a fivefold or more increase in inflammatory and angiogenic mediators; HRMPs secreted the greatest number and level of mediators. Dexamethasone dose dependently inhibited the secretion of multiple proteins from HRMPs and THP-1 cells, but not from HRECs (IC(50) 2 nM to 1 microM). High glucose, TNF-alpha, and IL-1beta induced an inflammatory phenotype in HRMPs, characterized by hypersecretion of inflammatory and angiogenic mediators. Dexamethasone at various potencies blocked hypersecretion of several proteins. Pericytes may be a key therapeutic target in retinal inflammatory diseases, including diabetic retinopathy. Inhibition of pathologic mediators may depend on delivering high levels ( approximately 1 microM) of glucocorticoid to the retina.

Dose of Phenobarbital and Age of Treatment at Early Life are Two Key Factors for the Persistent Induction of Cytochrome P450 Enzymes in Adult Mouse Liver

PubMed Central

Tien, Yun-Chen; Liu, Ke; Pope, Chad; Wang, Pengcheng; Ma, Xiaochao

2015-01-01

Drug treatment of neonates and infants and its long-term consequences on drug responses have emerged in recent years as a major challenge for health care professionals. In the current study, we use phenobarbital as a model drug and mouse as an in vivo model to demonstrate that the dose of phenobarbital and age of treatment are two key factors for the persistent induction of gene expression and consequential increases of enzyme activities of Cyp2b, Cyp2c, and Cyp3a in adult livers. We show that phenobarbital treatment at early life of day 5 after birth with a low dose (<100 mg/kg) does not change expression and enzyme activities of Cyp2b, Cyp2c, and Cyp3a in adult mouse liver, whereas phenobarbital treatment with a high dose (>200 mg/kg) significantly increases expression and enzyme activities of these P450s in adult liver. We also demonstrate that phenobarbital treatment before day 10 after birth, but not at later ages, significantly increases mRNAs, proteins, and enzyme activities of the tested P450s. Such persistent induction of P450 gene expression and enzyme activities in adult livers by phenobarbital treatment only occurs within a sensitive age window early in life. The persistent induction in gene expression and enzyme activities is higher in female mice than in male mice for Cyp2b10 but not for Cyp2c29 and Cyp3a11. These results will stimulate studies to evaluate the long-term impacts of drug treatment with different doses at neonatal and infant ages on drug metabolism, therapeutic efficacy, and drug-induced toxicity throughout the rest of life. PMID:26400395

Cytotoxic effects and apoptosis induction of enrofloxacin in hepatic cell line of grass carp (Ctenopharyngodon idellus).

PubMed

Liu, Bo; Cui, Yanting; Brown, Paul B; Ge, Xianping; Xie, Jun; Xu, Pao

2015-12-01

We determined the effect of enrofloxacin on the lactate dehydrogenase (LDH) release, reactive oxygen species (ROS), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), malondialdehyde (MDA), mitochondria membrane potential (ΔΨm) and apoptosis in the hepatic cell line of grass carp (Ctenopharyngodon idellus). Cultured cells were treated with different concentrations of enrofloxacin (12.5-200 ug/mL) for 24 h. We found that the cytotoxic effect of enrofloxacin was mediated by apoptosis, and that this apoptosis occurred in a dose-dependent manner. The doses of 50,100 and 200 μg/mL enrofloxacin increased the LDH release and MDA concentration, induced cell apoptosis and reduced the ΔΨm compared to the control. The highest dose of 200 ug/mL enrofloxacin also significantly induced apoptosis accompanied by ΔΨm disruption and ROS generation and significantly reduced T-AOC and increased MDA concentration compared to the control. Our results suggest that the dose of 200 ug/mL enrofloxacin exerts its cytotoxic effect and produced ROS via apoptosis by affecting the mitochondria of the hepatic cells of grass carp. Copyright © 2015 Elsevier Ltd. All rights reserved.

Kinetics model for initiation and promotion for describing tumor prevalence from HZE radiation

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.; Wilson, John W.

1994-01-01

A kinetics model for cellular repair and misrepair for multiple radiation-induced lesions (mutation-inactivation) is coupled to a two-mutation model of initiation and promotion in tissue to provide a parametric description of tumor prevalence in the Harderian gland in a mouse. Dose-response curves are described for gamma-rays and relativistic ions. The effects of nuclear fragmentation are also considered for high-energy proton and alpha particle exposures The model described provides a parametric description of age-dependent cancer induction for a wide range of radiation fields. We also consider the two hypotheses that radiation acts either solely as an initiator or as both initiator and promoter and make model calculations for fractionation exposures from gamma-rays and relativistic Fe ions. For fractionated Fe exposures, an inverse dose-rate effect is provided by a promotion hypothesis using a mutation rate for promotion typical of single-gene mutations.

Mechanisms of Radiation Toxicity in Transformed and Non-Transformed Cells

PubMed Central

Panganiban, Ronald-Allan M.; Snow, Andrew L.; Day, Regina M.

2013-01-01

Radiation damage to biological systems is determined by the type of radiation, the total dosage of exposure, the dose rate, and the region of the body exposed. Three modes of cell death—necrosis, apoptosis, and autophagy—as well as accelerated senescence have been demonstrated to occur in vitro and in vivo in response to radiation in cancer cells as well as in normal cells. The basis for cellular selection for each mode depends on various factors including the specific cell type involved, the dose of radiation absorbed by the cell, and whether it is proliferating and/or transformed. Here we review the signaling mechanisms activated by radiation for the induction of toxicity in transformed and normal cells. Understanding the molecular mechanisms of radiation toxicity is critical for the development of radiation countermeasures as well as for the improvement of clinical radiation in cancer treatment. PMID:23912235

Interactive lethal and mutagenic effects of ultraviolet light and bleomycin in yeast: synergism or antagonism?

PubMed

Lillo, O L; Severgnini, A A; Nunes, E M

1997-11-01

The mutagenic interactions of ultraviolet light and bleomycin in haploid populations of Saccharomyces cerevisiae were analyzed. Survival and mutation frequency as a function of different bleomycin concentrations after one conditioning dose of UV radiation were determined. Furthermore, corresponding interaction functions and sensitization factors were calculated. A synergistic interaction between UV light and bleomycin was shown for both lethal and mutagenic events when the cells were in nutrient broth during the treatments. Conversely, the interaction between UV light and bleomycin was antagonistic when the cells were in deionized water during the treatment. The magnitude of lethal and mutagenic interactions depends on dose, and thus presumably on the number of lesions. The observed interactions between UV light and bleomycin suggest that the mechanism that is most likely involved is the induction of repair systems with different error probabilities during the delay of cell division.

Thermal antinociception after dexmedetomidine administration in cats: a dose-finding study.

PubMed

Slingsby, L S; Taylor, P M

2008-04-01

The optimum dose of dexmedetomidine for antinociception to a thermal stimulus was determined in a crossover study of 12 cats. In five treatment groups (n = 10 per group), dexmedetomidine was administered intramuscularly (i.m.) at 2, 5, 10, 20 and 40 microg/kg; positive and negative controls were administered buprenorphine (20 microg/kg, i.m.) and 0.9% saline (0.006 mL/kg, i.m.) respectively. Baseline thermal thresholds and visual analogue scale (VAS) sedation scores were obtained prior to drug treatment and then at regular intervals until 24 h after administration. The summary measures of overall mean thresholds and overall mean VAS scores were investigated using a univariate general linear model for multiple factors with post hoc Tukey's tests (P < 0.05). Only dexmedetomidine at 40 microg/kg displayed an analgesic effect (less than that of buprenorphine). The VAS for sedation did not significantly affect the thresholds obtained and treatment was the only significant factor to influence VAS. Dexmedetomidine resulted in higher VAS for sedation than saline and buprenorphine. Dexmedetomidine at 40 microg/kg significantly increased nociceptive thresholds compared with saline control, but less than buprenorphine. Dexmedetomidine produced dose-dependent sedation, but only the highest dose produced analgesia, suggesting that induction of analgesia requires the highest dose (or an additional analgesic) in the clinical setting.

Treatment of Myasthenia Gravis Based on Its Immunopathogenesis

PubMed Central

Kim, Jee Young; Park, Kee Duk

2011-01-01

The prognosis of myasthenia gravis (MG) has improved dramatically due to advances in critical-care medicine and symptomatic treatments. Its immunopathogenesis is fundamentally a T-cell-dependent autoimmune process resulting from loss of tolerance toward self-antigens in the thymus. Thymectomy is based on this immunological background. For MG patients who are inadequately controlled with sufficient symptomatic treatment or fail to achieve remission after thymectomy, remission is usually achieved through the addition of other immunotherapies. These immunotherapies can be classified into two groups: rapid induction and long-term maintenance. Rapid induction therapy includes intravenous immunoglobulin (IVIg) and plasma exchange (PE). These produce improvement within a few days after initiation, and so are useful for acute exacerbation including myasthenic crisis or in the perioperative period. High-dose prednisone has been more universally preferred for remission induction, but it acts more slowly than IVIg and PE, commonly only after a delay of several weeks. Slow tapering of steroids after a high-dose pulse offers a method of maintaining the state of remission. However, because of significant side effects, other immunosuppressants (ISs) are frequently added as "steroid-sparing agents". The currently available ISs exert their immunosuppressive effects by three mechanisms: 1) blocking the synthesis of DNA and RNA, 2) inhibiting T-cell activation and 3) depleting the B-cell population. In addition, newer drugs including antisense molecule, tumor necrosis factor alpha receptor blocker and complement inhibitors are currently under investigation to confirm their effectiveness. Until now, the treatment of MG has been based primarily on experience rather than gold-standard evidence from randomized controlled trials. It is hoped that well-organized studies and newer experimental trials will lead to improved treatments. PMID:22259613

Cell cycle perturbations and genotoxic effects in human primary fibroblasts induced by low-energy protons and X/gamma-rays.

PubMed

Antoccia, Antonio; Sgura, Antonella; Berardinelli, Francesco; Cavinato, Maria; Cherubini, Roberto; Gerardi, Silvia; Tanzarella, Caterina

2009-09-01

The effect of graded doses of high-linear energy transfer (LET) low-energy protons to induce cycle perturbations and genotoxic damage was investigated in normal human fibroblasts. Furthermore, such effects were compared with those produced by low-LET radiations. HFFF2, human primary fibroblasts were exposed to either protons (LET = 28.5 keV/microm) or X/gamma-rays, and endpoints related to cell cycle kinetics and DNA damage analysed. Following both type of irradiations, unsynchronized cells suffered an inhibition to entry into S-phase for doses of 1-4 Gy and remained arrested in the G(1)-phase for several days. The levels of induction of regulator proteins, such as TP53 and CDKN1A showed a clear LET-dependence. DSB induction and repair as measured by scoring for gamma-H2AX foci indicated that protons, with respect to X-rays, yielded a lower number of DSBs per Gy, which showed a slower kinetics of disappearance. Such result was in agreement with the extent of MN induction in binucleated cells after X-irradiation. No significant differences between the two types of radiations were observed with the clonogenic assay, resulting anyway the slope of gamma-ray curve higher than that the proton one. In conclusion, in normal human primary fibroblasts cell cycle arrest at the G(1)/S transition can be triggered shortly after irradiation and maintained for several hours post-irradiation of both protons and X-rays. DNA damage produced by protons appears less amenable to be repaired and could be transformed in cytogenetic damage in the form of MN.

Effect of inhibition of polyamine biosynthesis by DL-alpha-difluoromethylornithine on the growth and melanogenesis of B16 melanoma in vitro and in vivo.

PubMed

Sunkara, P S; Chang, C C; Prakash, N J; Lachmann, P J

1985-09-01

The objective of the present study was to investigate the effect of polyamine depletion by alpha-difluoromethylornithine (DFMO), a specific irreversible inhibitor of ornithine decarboxylase, on the growth and differentiation of B16 melanoma cells grown in culture and also as solid tumors in mice. Polyamine depletion by DFMO (2.5 mM) resulted in a complete inhibition of cell growth in culture and a 90% inhibition of viability of melanoma cells as determined by clonogenic assay at the end of 7 days after DFMO treatment. These results indicate that polyamine depletion induced by DFMO is cytotoxic to B16 melanoma cells in culture. Furthermore a 2- to 5-fold increase in tyrosinase activity and 10-fold accumulation of melanine were observed in polyamine depleted cells compared to control cultures. These effects of DFMO could easily be reversed by the addition of putrescine simultaneously with DFMO. Administration of different doses of DFMO in drinking water to B16 melanoma tumor bearing mice also resulted in an increase in tyrosinase activity and a dose dependent inhibition (86-90%) of tumor growth. Although one cannot rule out the possibility of induction of differentiated phenotype as a result of antiproliferative activity of DFMO, the data presented indicate that the unique sensitivity of melanoma to DFMO may be due to a combination of cell growth inhibition and concomitant induction of differentiation upon polyamine depletion. The results of the present study indicate that polyamines play an important role in growth and differentiation of melanoma and also provide an example of inhibition of tumor cell growth by induction of cellular differentiation.

Analysis of Genotoxic and Cytotoxic Responses Induced by Simulated Space Radiation Qualities by Use of Recombinant Bacteria Carrying a Dual-Function Dual-Reporter Construct

NASA Astrophysics Data System (ADS)

Baumstark-Khan, Christa; Hellweg, Christine; Zahoor, Ahmed; Testard, Isabelle; Reitz, Guenther

Along with the long-term space exploration come various potential health risks due to unique physical factors of the space environment. Space radiation is one of the primary environmental hazards associated with space flight. In order to deal with space-related risk radiation exposure must be properly characterised and quantified, and biological effects of charged particles have to be analysed in ground based research, especially as astronauts are subjected to a differing radiation quality in space than they receive on Earth. For risk assessment, the mutagenic potential of the heavy ion component of the galactic cosmic radiation is of major concern for tumour induction as radiation late effects. The recombinant SWITCH test is based on TA1535 Salmonella typhimurium cells transformed with a dual-function dual-reporter vector harbouring (a) the genes for bioluminescence production from Photobacterium leiognathi under the control of a DNA-damage inducible promoter and (b) the gene for green fluorescent protein from the jellyfish Aequorea victoria under the control of a constitutive promoter. Suchlike genetically modified organism report on the presence of genotoxic conditions by dose dependent increase of bioluminescence induction and on the presence of cytotoxic conditions by dose dependent decrease in GFP fluorescence. By this, it is possible to analyse bacterial inactivation and mutation induction by ionizing radiation in parallel in the same cell within short time. Experiments with heavy ions have been performed with the SWITCH test at GANIL with the following accelerated heavy ions: 35 MeV/u (72 keV/µm) and 75 MeV/u (37 keV/µm) carbon, 95 MeV/u argon (377 keV/µm), 95 MeV/u neon (98 keV/µm), 75 MeV/u nickel (967 keV/µm) and 29 MeV/u lead (10238 keV/µm). The results obtained clearly show that the numbers of hits (particles per cm2 ) necessary to inactivate the bacteria (cytotoxicity) depend on LET. The higher the ionisation capacity of the accelerated ion, the less hits resulted in the same test effect, e.g. 37 % survival. For genotoxicity induction it can be seen, that for very high LET radiation the number of hits required is much less then for lower LET radiation (e.g. 1.4x106 /cm2 hits for lead versus 1.3x107 /cm2 hits for carbon). The power of the genotoxic response seems to be inversely related to LET. While 200 kV X-rays induced a 99.6x induction, carbon radiation results in a maximal induction of 72.6x (37 keV/m) and of 76.5x (72 keV/m), argon radiation (377 keV/m) leads to a 29.4x value, neon radiation (98 keV/m) leads to a 16.1x value, nickel radiation (967 keV/m) leads to a 15.4x value and lead radiation (10238 keV/m) results in only a factor of 4.8. Inactivation cross sections (σRCP) peak at a LET between 100 and 300 keV/m. The same is true for genotoxicity cross sections (σRGP for 2x), while maximal luminescence emission (for peak response) decreases with increasing LET. The response of the SWITCH test to space radiation qualities can be seen as indicative for an increased astronauts' risk from high LET radiation.

The efficacy of alfaxalone for immersion anesthesia in koi carp (Cyprinus carpio).

PubMed

Minter, Larry J; Bailey, Kate M; Harms, Craig A; Lewbart, Gregory A; Posner, Lysa P

2014-07-01

To characterize the physiologic and behavioral effects of a single induction dose and two maintenance doses of alfaxalone delivered by water immersion in the anesthesia of koi (Cyprinus carpio). Prospective, within-subject complete crossover design. Six adult koi (Cyprinus carpio) with a median body weight of 344.5 g (range 292.0-405.0 g). Koi were immersed in water containing 10 mg L(-1) alfaxalone until immobile and then maintained with alfaxalone at either 1 or 2.5 mg L(-1) via a recirculating water system. Times for anesthetic induction and recovery periods were recorded. Physiologic and blood gas parameters were evaluated before, during and after the anesthetic trial. Response to noxious stimuli was also assessed. Median anesthesia induction time for all fish was 5.4 minutes. Median recovery time was 11.8 and 26.4 minutes in the 1.0 and 2.5 mg L(-1) doses, respectively, which were significantly different (p = 0.04). Cessation of opercular movement occurred in 0/6 and 4/6 fish exposed to 1.0 and 2.5 mg L(-1) dose respectively. No difference was observed in median heart rate over the duration of the anesthetic events. Response to noxious stimulation was 4/6 and 0/6 in the 1.0 and 2.5 mg L(-1) doses respectively. Oxygenation and ventilation did not change during the experiment, but there was a significant decrease in blood pH along with an increase in blood lactate concentration. Administration of alfaxalone, via water immersion, as an induction and maintenance anesthesia agent provided rapid and reliable anesthesia of koi with no mortality. The maintenance dose of 2.5 mg L(-1) was sufficient to prevent response to noxious stimuli but was associated with a clinically relevant depression in opercular rate. © 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

Consumption of Dietary Resistant Starch Partially Corrected the Growth Pattern Despite Hyperglycemia and Compromised Kidney Function in Streptozotocin-Induced Diabetic Rats.

PubMed

Koh, Gar Yee; Rowling, Matthew J; Schalinske, Kevin L; Grapentine, Kelly; Loo, Yi Ting

2016-10-12

We previously demonstrated that feeding of dietary resistant starch (RS) prior to the induction of diabetes delayed the progression of diabetic nephropathy and maintained vitamin D balance in streptozotocin (STZ)-induced type 1 diabetic (T1D) rats. Here, we examined the impact of RS on kidney function and vitamin D homeostasis following STZ injection. Male Sprague-Dawley rats were administered STZ and fed a standard diet containing cornstarch or 20, 10, or 5% RS for 4 weeks. T1D rats fed 10 and 20% RS, but not 5% RS, gained more weight than cornstarch-fed rats. Yet, renal health and glucose metabolism were not improved by RS. Our data suggest that RS normalized growth patterns in T1D rats after diabetes induction in a dose-dependent manner despite having no effect on blood glucose and vitamin D balances. Future interventions should focus on the preventative strategies with RS in T1D.

Effect of citrus flavonoids on HL-60 cell differentiation.

PubMed

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

1999-01-01

Twenty-seven Citrus flavonoids were examined for their activity of induction of terminal differentiation of human promyelocytic leukemia cells (HL-60) by nitro blue tetrazolium (NBT) reducing, nonspecific esterase, specific esterase, and phagocytic activities. 10 flavonoids were judged to be active (percentage of NBT reducing cells was more than 40% at a concentration of 40 microM), and the rank order of potency was natsudaidain, luteolin, tangeretin, quercetin, apigenin, 3, 3, '4, '5, 6, 7, 8-heptamethoxyflavone, nobiletin, acacetin, eriodictyol, and taxifolin. These flavonoids exerted their activity in a dose-dependent manner. HL-60 cells treated with these flavonoids differentiated into mature monocyte/macrophage. The structure-activity relationship established from comparison between flavones and flavanones revealed that ortho-catechol moiety in ring B and C2-C3 double bond had an important role for induction of differentiation of HL-60. In polymethoxylated flavones, hydroxyl group at C3 and methoxyl group at C8 enhanced the differentiation-inducing activity.

Synergistic induction of cytogenetic damage by the homo-aza-steroidal ester of p-bis(2-chloroethyl)aminophenylacetic acid in combination with caffeine in human lymphocytes in vitro and in Ehrlich ascites tumour cells in vivo.

PubMed

Petrou, C; Mourelatos, D; Dozi-Vassiliades, J; Catsoulacos, P

1990-02-01

We studied the effects of caffeine alone or in combination with homo-aza-steroidal ester of p-bis(2-chloroethyl)aminophenylacetic acid (ASE, NSC 290205) on the frequency of SCEs and lymphocyte proliferation kinetics. Caffeine was found to act synergistically with ASE on the induction of SCEs when the two components were administered in combination. Caffeine was also found to act synergistically with ASE in inducing cell-division delays. Enhanced cytogenetic damage by ASE was observed when Ehrlich ascites tumour cells (EAT cells) were exposed in vivo to caffeine. ASE alone or in combination with caffeine caused a dose-dependent increase in SCE rates and cell-division delays. SCEs were demonstrated in EAT-bearing mice, by the i.p. injection of BrdUrd adsorbed onto activated charcoal, 1 h after the i.p. injection of ASE and/or caffeine.

Effects of karanjin on cell cycle arrest and apoptosis in human A549, HepG2 and HL-60 cancer cells.

PubMed

Guo, Jian-Ru; Chen, Qian-Qian; Lam, Christopher Wai-Kei; Zhang, Wei

2015-07-26

We have investigated the potential anticancer effects of karanjin, a principal furanoflavonol constituent of the Chinese medicine Fordia cauliflora, using cytotoxic assay, cell cycle arrest, and induction of apoptosis in three human cancer cell lines (A549, HepG2 and HL-60 cells). MTT cytotoxic assay showed that karanjin could inhibit the proliferation and viability of all three cancer cells. The induction of cell cycle arrest was observed via a PI (propidium iodide)/RNase Staining Buffer detection kit and analyzed by flow cytometry: karanjin could dose-dependently induce cell cycle arrest at G2/M phase in the three cell lines. Cell apoptosis was assessed by Annexin V-FITC/PI staining: all three cancer cells treated with karanjin exhibited significantly increased apoptotic rates, especially in the percentage of late apoptosis cells. Karanjin can induce cancer cell death through cell cycle arrest and enhance apoptosis. This compound may be effective clinically for cancer pharmacotherapy.

Brain insulin lowers circulating BCAA levels by inducing hepatic BCAA catabolism

PubMed Central

Shin, Andrew C.; Fasshauer, Martin; Filatova, Nika; Grundell, Linus A.; Zielinski, Elizabeth; Zhou, Jian-Ying; Scherer, Thomas; Lindtner, Claudia; White, Phillip J.; Lapworth, Amanda L.; Ilkayeva, Olga; Knippschild, Uwe; Wolf, Anna M.; Scheja, Ludger; Grove, Kevin L.; Smith, Richard D.; Qian, Wei-Jun; Lynch, Christopher J.; Newgard, Christopher B.; Buettner, Christoph

2014-01-01

Summary Circulating branched-chain amino acid (BCAA) levels are elevated in obesity/diabetes and are a sensitive predictor for type 2 diabetes. Here we show in rats that insulin dose-dependently lowers plasma BCAA levels through induction of hepatic protein expression and activity of branched-chain α keto-acid dehydrogenase (BCKDH), the rate-limiting enzyme in the BCAA degradation pathway. Selective induction of hypothalamic insulin signaling in rats and genetic modulation of brain insulin receptors in mice demonstrate that brain insulin signaling is a major regulator of BCAA metabolism by inducing hepatic BCKDH. Short-term overfeeding impairs the ability of brain insulin to lower BCAAs in rats. High-fat feeding in non-human primates and obesity and/or diabetes in humans is associated with reduced BCKDH protein in liver. These findings support the concept that decreased hepatic BCKDH is a major cause of increased plasma BCAAs, and that hypothalamic insulin resistance may account for impaired BCAA metabolism in obesity and diabetes. PMID:25307860

Apoptogenic effects of β-sitosterol glucoside from Castanopsis indica leaves.

PubMed

Dolai, Narayan; Kumar, Ashish; Islam, Aminul; Haldar, Pallab K

2016-01-01

β-Sitosterol glucoside (BSSG) is a natural biologically active substance isolated from the Castanopsis indica leaves. This study explored the apoptogenic mechanistic studies of BSSG against Ehrlich's ascites carcinoma (EAC) treated mice through morphological study, comet assay, flow cytometry (FACS) and Western blotting assay method. AO/EB staining and FACS analysis showed that BSSG possessed apoptosis induction activities on EAC cells. Dose dependent induction of DNA damage was observed after BSSG treatment. Increase the expression of apoptotic protein p53 and p21 in EAC, multiple downstream factors contributing to apoptosis pathway. The increase of caspase-9 and caspase-3 activities revealed that caspase was a key mediator of the apoptotic pathway induced by BSSG, and up-regulation of Bax and down-regulation of anti-apoptotic protein Bcl-2 resulted in the decrease of Bcl-2/Bax ratio. Owing to the combination of significant antitumour activity by inducing apoptosis, BSSG holds the promise of being an interesting chemo-preventive agent active in cancer therapy.

Brain insulin lowers circulating BCAA levels by inducing hepatic BCAA catabolism.

PubMed

Shin, Andrew C; Fasshauer, Martin; Filatova, Nika; Grundell, Linus A; Zielinski, Elizabeth; Zhou, Jian-Ying; Scherer, Thomas; Lindtner, Claudia; White, Phillip J; Lapworth, Amanda L; Ilkayeva, Olga; Knippschild, Uwe; Wolf, Anna M; Scheja, Ludger; Grove, Kevin L; Smith, Richard D; Qian, Wei-Jun; Lynch, Christopher J; Newgard, Christopher B; Buettner, Christoph

2014-11-04

Circulating branched-chain amino acid (BCAA) levels are elevated in obesity/diabetes and are a sensitive predictor for type 2 diabetes. Here we show in rats that insulin dose-dependently lowers plasma BCAA levels through induction of hepatic protein expression and activity of branched-chain α-keto acid dehydrogenase (BCKDH), the rate-limiting enzyme in the BCAA degradation pathway. Selective induction of hypothalamic insulin signaling in rats and genetic modulation of brain insulin receptors in mice demonstrate that brain insulin signaling is a major regulator of BCAA metabolism by inducing hepatic BCKDH. Short-term overfeeding impairs the ability of brain insulin to lower BCAAs in rats. High-fat feeding in nonhuman primates and obesity and/or diabetes in humans is associated with reduced BCKDH protein in liver. These findings support the concept that decreased hepatic BCKDH is a major cause of increased plasma BCAAs and that hypothalamic insulin resistance may account for impaired BCAA metabolism in obesity and diabetes. Copyright © 2014 Elsevier Inc. All rights reserved.

Induction of caspase-dependent extrinsic apoptosis by apigenin through inhibition of signal transducer and activator of transcription 3 (STAT3) signalling in HER2-overexpressing BT-474 breast cancer cells.

PubMed

Seo, Hye-Sook; Jo, Jae Kyung; Ku, Jin Mo; Choi, Han-Seok; Choi, Youn Kyung; Woo, Jong-Kyu; Kim, Hyo In; Kang, Soo-Yeon; Lee, Kang Min; Nam, Koong Won; Park, Namkyu; Jang, Bo-Hyoung; Shin, Yong Cheol; Ko, Seong-Gyu

2015-10-23

Phytoestrogen intake is known to be beneficial to decrease breast cancer incidence and progression. But its molecular mechanisms of action are still unknown. The present study aimed to examine the effect of apigenin on proliferation and apoptosis in HER2-expressing breast cancer cells. In our experiments, apigenin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Apigenin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Apigenin-induced extrinsic a caspase-dependent apoptosis up-regulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly (ADP-ribose) polymerase (PARP). Whereas, apigenin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease mitochondrial membrane potential without affecting the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Apigenin reduced the expression of phospho-JAK1, phospho-JAK2 and phospho-STAT3 and decreased signal transducer and activator of transcription 3 (STAT3) dependent luciferase reporter gene activity in BT-474 cells. Apigenin inhibited CoCl2-induced VEGF secretion and decreased the nuclear translocation of STAT3. Our study indicates that apigenin induces apoptosis through inhibition of STAT3 signalling and could serve as a useful compound to prevent or treat HER2-overexpressing breast cancer. © 2015 Authors.

Induction of caspase-dependent extrinsic apoptosis by apigenin through inhibition of signal transducer and activator of transcription 3 (STAT3) signalling in HER2-overexpressing BT-474 breast cancer cells

PubMed Central

Seo, Hye-Sook; Jo, Jae Kyung; Ku, Jin Mo; Choi, Han-Seok; Choi, Youn Kyung; Woo, Jong-Kyu; in Kim, Hyo; Kang, Soo-yeon; Lee, Kang min; Nam, Koong Won; Park, Namkyu; Jang, Bo-Hyoung; Shin, Yong Cheol; Ko, Seong-Gyu

2015-01-01

Phytoestrogen intake is known to be beneficial to decrease breast cancer incidence and progression. But its molecular mechanisms of action are still unknown. The present study aimed to examine the effect of apigenin on proliferation and apoptosis in HER2-expressing breast cancer cells. In our experiments, apigenin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Apigenin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Apigenin-induced extrinsic a caspase-dependent apoptosis up-regulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly (ADP-ribose) polymerase (PARP). Whereas, apigenin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease mitochondrial membrane potential without affecting the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Apigenin reduced the expression of phospho-JAK1, phospho-JAK2 and phospho-STAT3 and decreased signal transducer and activator of transcription 3 (STAT3) dependent luciferase reporter gene activity in BT-474 cells. Apigenin inhibited CoCl2-induced VEGF secretion and decreased the nuclear translocation of STAT3. Our study indicates that apigenin induces apoptosis through inhibition of STAT3 signalling and could serve as a useful compound to prevent or treat HER2-overexpressing breast cancer. PMID:26500281

Modulation of morphine antinociceptive tolerance and physical dependence by co-administration of simvastatin.

PubMed

Mansouri, Mohammad Taghi; Khodayar, Mohammad Javad; Tabatabaee, Amirhossein; Ghorbanzadeh, Behnam; Naghizadeh, Bahareh

2015-10-01

Statins, 3-hydroxy-3-methylglutaryl co-enzyme A (HMG-CoA) reductase inhibitors, are widely used in the management of different diseases beyond their primary indication for lowering cholesterol. Previous studies have demonstrated the neuroprotective effects of simvastatin in different animal models. In the present study, we examined the effects of simvastatin (30, 60, 100 and 300mg/kg, p.o.) on the development and expression of morphine-induced tolerance and dependence in mice. For the induction of morphine tolerance and dependence, mice were twice daily treated with morphine (10mg/kg, s.c.) for 5 consecutive days. Tolerance was evaluated by the hot-plate test and physical dependence by naloxone challenge, on the sixth day. The results showed that oral administration of simvastatin produced antinociceptive activity in a dose-dependent way. Co-administration of simvastatin with morphine did not affect the acute morphine-induced analgesia (10mg/kg, s.c.). However, repeated co-administration of simvastatin with morphine significantly attenuated the development of tolerance to the analgesic effect of morphine and inhibited the naloxone (5mg/kg, s.c.)-precipitated withdrawal signs (jumping and body weight loss). Also, simvastatin at doses of 100 and 300mg/kg attenuated the expression of morphine-induced tolerance and dependence. These data indicated that, while simvastatin can alleviate both development and expression of morphine-induced tolerance, it cannot enhance morphine-induced antinociception. Taken together, simvastatin may be used as an adjutant therapeutic agent in combination with morphine and or other opioids in patients with severe chronic pain. Copyright © 2015 Elsevier Inc. All rights reserved.

Protection of ionizing radiation-induced cytogenetic damage by hydroalcoholic extract of Cynodon dactylon in Chinese hamster lung fibroblast cells and human peripheral blood lymphocytes.

PubMed

Rao, Bola Sadashiva Satish; Upadhya, Dinesh; Adiga, Satish Kumar

2008-01-01

The radiomodulatory potential of hydroalcoholic extract of a medicinal plant Cynodon dactylon (family: Poaceae) against radiation-induced cytogenetic damage was analyzed using Chinese hamster lung fibroblast (V79) cells and human peripheral blood lymphocytes (HPBLs) growing in vitro. Induction of micronuclei was used as an index of cytogenetic damage, evaluated in cytokinesis blocked binucleate cells. The hydroalcoholic Cynodon dactylon extract (CDE) rendered protection against the radiation-induced DNA damage, as evidenced by the significant (p<0.001) reduction in micronucleated binucleate cells (MNBNC%) after various doses of CDE treatment in V79 cells and HPBLs. The optimum dose of CDE (40 and 50 microg/ml in HPBLs and V79 cells, respectively) with the greatest reduction in micronuclei was further used in combination with various doses of gamma radiation (0.5, 1, 2, 3, and 4 Gy) exposed 1 h after CDE treatment. A linear dose-dependent MNBNC% increase in radiation alone group was observed, while 40/50 microg/ml CDE significantly resulted in the reduction of MNBNC%, compared to the respective radiation alone groups. CDE resulted in a dose-dependent increase in free radical scavenging ability against various free radicals, viz., 2, 2-diphenyl-2-picryl-hydrazyl (DPPH); 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS); superoxide anion (O2*-); hydroxyl radical (OH*) and nitric oxide radical (NO*) generated in vitro. Also, an excellent (70%) inhibition of lipid peroxidation in vitro was observed at a dose of 300 microg/ml CDE, attaining the saturation point at higher doses. The present findings demonstrated the radioprotective effect of CDE, also rendering protection against radiation-induced genomic instability and DNA damage. The observed radioprotective effect may be partly attributed to the free radical scavenging and antilipid peroxidative potential of CDE.

28Si total body irradiation injures bone marrow hematopoietic stem cells via induction of cellular apoptosis

NASA Astrophysics Data System (ADS)

Chang, Jianhui; Feng, Wei; Wang, Yingying; Allen, Antiño R.; Turner, Jennifer; Stewart, Blair; Raber, Jacob; Hauer-Jensen, Martin; Zhou, Daohong; Shao, Lijian

2017-05-01

Long-term space mission exposes astronauts to a radiation environment with potential health hazards. High-energy charged particles (HZE), including 28Si nuclei in space, have deleterious effects on cells due to their characteristics with high linear energy transfer and dense ionization. The influence of 28Si ions contributes more than 10% to the radiation dose equivalent in the space environment. Understanding the biological effects of 28Si irradiation is important to assess the potential health hazards of long-term space missions. The hematopoietic system is highly sensitive to radiation injury and bone marrow (BM) suppression is the primary life-threatening injuries after exposure to a moderate dose of radiation. Therefore, in the present study we investigated the acute effects of low doses of 28Si irradiation on the hematopoietic system in a mouse model. Specifically, 6-month-old C57BL/6 J mice were exposed to 0.3, 0.6 and 0.9 Gy 28Si (600 MeV) total body irradiation (TBI). The effects of 28Si TBI on BM hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) were examined four weeks after the exposure. The results showed that exposure to 28Si TBI dramatically reduced the frequencies and numbers of HSCs in irradiated mice, compared to non-irradiated controls, in a radiation dose-dependent manner. In contrast, no significant changes were observed in BM HPCs regardless of radiation doses. Furthermore, irradiated HSCs exhibited a significant impairment in clonogenic ability. These acute effects of 28Si irradiation on HSCs may be attributable to radiation-induced apoptosis of HSCs, because HSCs, but not HPCs, from irradiated mice exhibited a significant increase in apoptosis in a radiation dose-dependent manner. However, exposure to low doses of 28Si did not result in an increased production of reactive oxygen species and DNA damage in HSCs and HPCs. These findings indicate that exposure to 28Si irradiation leads to acute HSC damage.

Chronic administration of phenytoin induces efflux transporter overexpression in rats.

PubMed

Alvariza, Silvana; Fagiolino, Pietro; Vázquez, Marta; Feria-Romero, Iris; Orozco-Suárez, Sandra

2014-12-01

Efflux transporters overexpression has been proposed as one of the responsible mechanism for refractory epilepsy by preventing access of the antiepileptic drug to the brain. In this work we investigated whether phenytoin (PHT), could induce efflux transporters overexpression, at different biological barriers and to evaluate the implication it could have on its pharmacokinetics and therapeutic/toxic response. Forty-two adult females Sprague Dawley divided in five groups were treated with oral doses of 25, 50 and 75mg/kg/6h of PHT for 3 days and two additionally groups were treated with intraperitoneal (ip) doses of 25mg/kg/6h or 100mg/kg/24h. At day 4 PHT plasma concentrations were measured and, obtained several organs, brain, parotid gland, liver and duodenum in which were analyzed for the Pgp expression. At day 4 PHT plasma concentrations were measured and several tissues: brain, parotid gland, liver and duodenum were obtained in order to analyze Pgp expression. In order to evaluate the oral bioavailability of PHT, two groups were administered with oral or intraperitoneal doses of 100mg/kg and plasma level were measured. An induction of the expression of efflux transporter mediated by phenytoin in a concentration-and-time dependent manner was found when increasing oral and ip doses of phenytoin, One week after the interruption of ip treatment a basal expression of transporters was recovered. Overexpression of efflux transporters can be mediated by inducer agents like PHT in a local-concentration dependent manner, and it is reversible once the substance is removed from the body. The recovery of basal Pgp expression could allow the design of dosing schedules that optimize anticonvulsant therapy. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Sulforaphane targets cancer stemness and tumor initiating properties in oral squamous cell carcinomas via miR-200c induction.

PubMed

Liu, Chia-Ming; Peng, Chih-Yu; Liao, Yi-Wen; Lu, Ming-Yi; Tsai, Meng-Lun; Yeh, Jung-Chun; Yu, Chuan-Hang; Yu, Cheng-Chia

2017-01-01

Cancer stem cells (CSCs) are deemed as the driving force of tumorigenesis in oral squamous cell carcinomas (OSCCs). In this study, we investigated the chemotherapeutic effect of sulforaphane, a dietary component from broccoli sprouts, on targeting OSCC-CSCs. The effect of sulforaphane on normal oral epithelial cells (SG) and sphere-forming OSCC-CSCs isolated from SAS and GNM cells was examined. ALDH1 activity and CD44 positivity of OSCC-CSCs with sulforaphane treatment was assessed by flow cytometry analysis. In vitro and in vivo tumorigenicity assays of OSCC-CSCs with sulforaphane treatment were presented. We observed that the sulforaphane dose-dependently eliminated the proliferation rate of OSCC-CSCs, whereas the inhibition on SG cells proliferation was limited. Cancer stemness properties including self-renewal, CD44 positivity, and ALDH1 activity were also decreased in OSCC-CSCs with different doses of sulforaphane treatment. Moreover, sulforaphane treatment of OSCC-CSCs decreased the migration, invasion, clonogenicity, and in vivo tumorigenicity of xenograghts. Sulforaphane treatment resulted in a dose-dependent increase in the levels of tumor suppressive miR200c. These lines of evidence suggest that sulforaphane can suppress the cancer stemness and tumor-initiating properties in OSCC-CSCs both in vitro and in vivo. Copyright © 2016. Published by Elsevier B.V.

[Mechanism of apoptosis of nasopharyngeal carcinoma cells induced by polysaccharides extracts from Hedyotic diffusa].

PubMed

Jing Yan; Kang Min; Liu Jin; Li Jingyu; Tang Anzhou

2015-04-01

To explore the proliferation inhibition and apoptosis of polysaccharides extracts from polysaccharides extracts from Hedyotic diffusa (PEHD) on Human Nasopharyngeal Carcinoma (NPC)cell line CNE2 cells in vitro. CNE2 cells treated with various concentrations of PEHD were detected by MTT assay at 24 h, 48 h, and 72 h. The apoptotic cells were analyzed by flow cytometry with Annexin V/PI staining. The expression levels of Bax, Bcl-2 and caspase-3 protein were examined by Western blotting method. The growth of CNE2 cells were suppressed after treatment with PEHD (P < 0.05), MTT assay showed that the highest cell inhibition rate reached to 76.5%, the inhibition in the doses from 2 to 6 mg/ml showed dose-and-time-dependent. The percent of apoptosis in 4 and 6 mg/ml PEHD treatment groups for 48 h were 31.32%, 46.28%, respectively, and significantly higher than that in control groups, 4.86% (P < 0.01). After the cells being treated with PEHD for 48 h, the expression of Bax and caspase-3 protein increased, and the expression of Bcl-2 protein decreased gradually. PEHD could inhibited the growth of CNE2 cells and was dose-and-time-dependent, the mechanism may involve induction of cell apoptosis, which was associated with the activation of Bax and caspase-3 protein and the down-regulation of Bcl-2 protein expression.

Anti-tumor effects and apoptosis induction by Realgar bioleaching solution in Sarcoma-180 cells in vitro and transplanted tumors in mice in vivo.

PubMed

Xie, Qin-Jian; Cao, Xin-Li; Bai, Lu; Wu, Zheng-Rong; Ma, Ying-Ping; Li, Hong-Yu

2014-01-01

Realgar which contains arsenic components has been used in traditional Chinese medicine (TCM) as an anticancer drug. However, neither Realgar nor its formula are soluble in water. As a result, high dose of Realgar has to be administered to achieve an effective blood medicine concentration, and this is associated with adverse side effects. The objective of the present study was to increase the solubility of a formula using hydrometallurgy technology as well as investigating its effects on in vitro and in vivo cell proliferation and apoptosis in Sarcoma-180 cell line. Antiproliferative activity of Realgar Bioleaching Solution (RBS) was evaluated by MTT assay. Further, effects of RBS on cell proliferation and apoptosis were studied using flow cytometry and transmission electron microscopy. Kunming mice were administered RBS in vivo, where arsenic specifically targeted solid tumors. The results indicated that RBS extract potently inhibited the tumor growth of Sarcoma-180 cell line in a dose-dependent manner. Flow cytometry and transmission electron microscopy further indicated that RBS significantly induced cell apoptosis through the inhibition of cell cycle pathway in a dose-dependent manner. Further, on RBS administration to mice, arsenic was specifically targeted to solid tumors RBS could substitute for traditional Realgar or its formula to work as a potent tool in cancer treatment.

Comparison of hemodynamic effects of intravenous etomidate versus propofol during induction and intubation using entropy guided hypnosis levels.

PubMed

Shah, Shagun Bhatia; Chowdhury, Itee; Bhargava, Ajay Kumar; Sabbharwal, Bhawnish

2015-01-01

This study aimed to compare the hemodynamic responses during induction and intubation between propofol and etomidate using entropy guided hypnosis. Sixty ASA I & II patients in the age group 20-60 yrs, scheduled for modified radical mastectomy were randomly allocated in two groups based on induction agent Etomidate or Propofol. Both groups received intravenous midazolam 0.03 mg kg(-1) and fentanyl 2 μg kg(-1) as premedication. After induction with the desired agent titrated to entropy 40, vecuronium 0.1 mg kg(-1) was administered for neuromuscular blockade. Heart rate, systolic, diastolic and mean arterial pressures, response entropy [RE] and state entropy [SE] were recorded at baseline, induction and upto three minutes post intubation. Data was subject to statistical analysis SPSS (version 12.0) the paired and the unpaired Student's T-tests for equality of means. Etomidate provided hemodynamic stability without the requirement of any rescue drug in 96.6% patients whereas rescue drug ephedrine was required in 36.6% patients in propofol group. Reduced induction doses 0.15mg kg(-1) for etomidate and 0.98 mg kg(-1) for propofol, sufficed to give an adequate anaesthetic depth based on entropy. Etomidate provides more hemodynamic stability than propofol during induction and intubation. Reduced induction doses of etomidate and propofol titrated to entropy translated into increased hemodynamic stability for both drugs and sufficed to give an adequate anaesthetic depth.

Comparison of hemodynamic effects of intravenous etomidate versus propofol during induction and intubation using entropy guided hypnosis levels

PubMed Central

Shah, Shagun Bhatia; Chowdhury, Itee; Bhargava, Ajay Kumar; Sabbharwal, Bhawnish

2015-01-01

Background and Aims: This study aimed to compare the hemodynamic responses during induction and intubation between propofol and etomidate using entropy guided hypnosis. Material and Methods: Sixty ASA I & II patients in the age group 20-60 yrs, scheduled for modified radical mastectomy were randomly allocated in two groups based on induction agent Etomidate or Propofol. Both groups received intravenous midazolam 0.03 mg kg-1 and fentanyl 2 μg kg-1 as premedication. After induction with the desired agent titrated to entropy 40, vecuronium 0.1 mg kg-1 was administered for neuromuscular blockade. Heart rate, systolic, diastolic and mean arterial pressures, response entropy [RE] and state entropy [SE] were recorded at baseline, induction and upto three minutes post intubation. Data was subject to statistical analysis SPSS (version 12.0) the paired and the unpaired Student's T-tests for equality of means. Results: Etomidate provided hemodynamic stability without the requirement of any rescue drug in 96.6% patients whereas rescue drug ephedrine was required in 36.6% patients in propofol group. Reduced induction doses 0.15mg kg-1 for etomidate and 0.98 mg kg-1 for propofol, sufficed to give an adequate anaesthetic depth based on entropy. Conclusion: Etomidate provides more hemodynamic stability than propofol during induction and intubation. Reduced induction doses of etomidate and propofol titrated to entropy translated into increased hemodynamic stability for both drugs and sufficed to give an adequate anaesthetic depth. PMID:25948897

High dose cytarabine and mitoxantrone: an effective induction regimen for high-risk acute myeloid leukemia (AML).

PubMed

Larson, Sarah M; Campbell, Nicholas P; Huo, Dezheng; Artz, Andrew; Zhang, Yanming; Gajria, Devika; Green, Margaret; Weiner, Howie; Daugherty, Christopher; Odenike, Olatoyosi; Godley, Lucy A; Hyjek, Elizabeth; Gurbuxani, Sandeep; Thirman, Michael; Sipkins, Dorothy; Van Besien, Koen; Larson, Richard A; Stock, Wendy

2012-03-01

Patients with high-risk AML, defined as those with advanced age, relapsed/refractory disease, unfavorable molecular and cytogenetic abnormalities, therapy-related myeloid neoplasm (t-MN) and multiple medical co-morbidities tend to respond poorly to standard cytarabine and daunorubicin induction therapy and have a poor prognosis. We performed a retrospective analysis of an alternative induction regimen using high dose cytarabine (HiDAC) and mitoxantrone (MITO) administered to 78 high-risk patients with AML at The University of Chicago from 2001 to 2008. The primary endpoints of the study were complete remission (CR) rate and death within 30 days of initiation of treatment. The median age was 63 years (range:23-85); 27% of these patients had a Charlson co-morbidity index (CCI) > 2. Forty-three (56%) patients had unfavorable cytogenetics, 28 (37%) had intermediate-risk cytogenetics and 5 (7%) had favorable cytogenetics. The CR rate was 45% and the CRi rate 10%; 7 patients (9%) died during induction. Notably, t-MN and relapsed/refractory patients had CR and induction death rates equivalent to de novo AML patients within this series. In this high risk AML population, HiDAC/MITO induction demonstrated an overall response rate of 55% with a low induction death rate of 9% and allowed 32 (41%) patients to proceed to allogeneic stem cell transplant.

Effects of caffeine on locomotor activity in streptozotocin-induced diabetic rats

PubMed Central

Bădescu, SV; Tătaru, CP; Kobylinska, L; Georgescu, EL; Zahiu, DM; Zăgrean, AM; Zăgrean, L

2016-01-01

Diabetes mellitus modifies the expression of adenosine receptors in the brain. Caffeine acts as an antagonist of A1 and A2A adenosine receptors and was shown to have a dose-dependent biphasic effect on locomotion in mice. The present study investigated the link between diabetes and locomotor activity in an animal model of streptozotocin-induced diabetes, and the effects of a low-medium dose of caffeine in this relation. The locomotor activity was investigated by using Open Field Test at 6 weeks after diabetes induction and after 2 more weeks of chronic caffeine administration. Diabetes decreased locomotor activity (total distance moved and mobility time). Chronic caffeine exposure impaired the locomotor activity in control rats, but not in diabetic rats. Our data suggested that the medium doses of caffeine might block the A2A receptors, shown to have an increased density in the brain of diabetic rats, and improve or at least maintain the locomotor activity, offering a neuroprotective support in diabetic rats. Abbreviations: STZ = streptozotocin, OFT = Open Field Test PMID:27974933

The pharmacodynamics of thymomodulin in elderly humans.

PubMed

Calsini, P; Mocchegiani, E; Fabris, N

1985-01-01

It has been shown that, after oral administration of thymomodulin (Leucotrofina, Ellem Industria Farmaceutica SpA, Milan, Italy) nude mice show in their sera inductive activity on null cells, as measured by the Thy 1.2 antigen bioassay. The appearance of thymic hormone-like activity, as measured by the rosette inhibition assay, was investigated after oral administration of thymomodulin in elderly humans, who show no detectable levels of FTS ("facteur thymique sérique") in their serum. In human subjects over 70 years old, thymomodulin administration induced the appearance of FTS-like activity which reached maximum level at 2-6 h, was maintained for up to 12 h and disappeared by the 48th hour. By using different thymomodulin doses (80, 160, 320, 640, 800 mg) in a single administration, a dose-dependent effect appeared to exist: the higher the dose, the longer the maintenance of FTS levels. These data suggest that oral administration of thymomodulin induces, in humans, the appearance in the serum of substances with a modulating effect on the maturation of T-cells, and that the intestinal absorption of thymomodulin is efficient also in advanced age.

Effect of 60Co gamma radiation on Biomphalaria glabrata (Mollusca, Gastropoda) embryos: mortality, malformation and hatching.

PubMed

Okazaki, K; Andrade Júnior, H F; Kawano, T

1996-08-01

A study was carried out on the radiosensitivity of Biomphalaria glabrata embryos submitted to doses of 5, 10, 15, 20 and 25 Gy of 60Co during the cleavage, blastula, gastrula, young trochophore and trochophore stages. Mortality, malformation and hatching were the parameters used to evaluate the damage induced by ionizing radiation. Estimated LD50 values (15 days) showed that the cleavage stage (4.3 Gy) was approximately four times more radiosensitive than the trochophore stage (17.0 Gy). Susceptibility to malformation induction was higher in the blastula, gastrula and young trochophore stages. Several types of morphogenetic malformations were observed, such as head malformations, exogastrulas, shell malformations, and embryos with everted stomodeum, with nonspecific malformations being the most frequent. The types of malformation induced by radiation probably are not radiation-specific and do not depend on the dose applied. The dose of 15 Gy was sufficient to greatly reduce the number of hatching snails regardless of the embryonic stage irradiated. We conclude that the effect of 60Co gamma radiation on B. glabrata embryos presented a specific pattern.

Jasmonic acid-induced volatiles of Brassica oleracea attract parasitoids: effects of time and dose, and comparison with induction by herbivores

PubMed Central

Bruinsma, Maaike; Posthumus, Maarten A.; Mumm, Roland; Mueller, Martin J.; van Loon, Joop J. A.; Dicke, Marcel

2009-01-01

Caterpillar feeding induces direct and indirect defences in brassicaceous plants. This study focused on the role of the octadecanoid pathway in induced indirect defence in Brassica oleracea. The effect of induction by exogenous application of jasmonic acid (JA) on the responses of Brussels sprouts plants and on host-location behaviour of associated parasitoid wasps was studied. Feeding by the biting–chewing herbivores Pieris rapae and Plutella xylostella resulted in significantly increased endogenous levels of JA, a central component in the octadecanoid signalling pathway that mediates induced plant defence. The levels of the intermediate 12-oxophyto-dienoic acid (OPDA) were significantly induced only after P. rapae feeding. Three species of parasitoid wasps, Cotesia glomerata, C. rubecula, and Diadegma semiclausum, differing in host range and host specificity, were tested for their behavioural responses to volatiles from herbivore-induced, JA-induced, and non-induced plants. All three species were attracted to volatiles from JA-induced plants compared with control plants; however, they preferred volatiles from herbivore-induced plants over volatiles from JA-induced plants. Attraction of C. glomerata depended on both timing and dose of JA application. JA-induced plants produced larger quantities of volatiles than herbivore-induced and control plants, indicating that not only quantity, but also quality of the volatile blend is important in the host-location behaviour of the wasps. PMID:19451186

Silymarin inhibits melanoma cell growth both in vitro and in vivo by targeting cell cycle regulators, angiogenic biomarkers and induction of apoptosis.

PubMed

Vaid, Mudit; Singh, Tripti; Prasad, Ram; Katiyar, Santosh K

2015-11-01

Cutaneous malignant melanoma is the leading cause of death from skin diseases and is often associated with activating mutations of the proto-oncogene BRAF. To develop more effective strategies for the prevention or treatment of melanoma, we have examined the inhibitory effects of silymarin, a flavanoid from Silybum marianum, on melanoma cells. Using A375 (BRAF-mutated) and Hs294t (non BRAF-mutated but highly metastatic) human melanoma cell lines, we found that in vitro treatment with silymarin resulted in a dose-dependent: (i) reduction in cell viability; (ii) enhancement of either Go/G1 (A375) or G2-M (Hs294t) phase cell cycle arrest with corresponding alterations in cyclins and cyclin-dependent kinases; and (iii) induction of apoptosis. The silymarin-induced apoptosis of human melanoma cells was associated with a reduction in the levels of anti-apoptotic proteins (Bcl-2 and Bcl-xl), an increase in the levels of pro-apoptotic protein (Bax), and activation of caspases. Further, oral administration of silymarin (500 mg/kg body weight/2× a week) significantly inhibited (60%, P < 0.01) the growth of BRAF-mutated A375 melanoma tumor xenografts, and this was associated with: (i) inhibition of cell proliferation; (ii) induction of apoptosis of tumor cells; (iii) alterations in cell cycle regulatory proteins; and (iv) reduced expression of tumor angiogenic biomarkers in tumor xenograft tissues. These results indicate that silymarin may have a chemotherapeutic effect on human melanoma cell growth and warrant its further evaluation. © 2014 Wiley Periodicals, Inc.

Human milk hyaluronan enhances innate defense of the intestinal epithelium.

PubMed

Hill, David R; Rho, Hyunjin K; Kessler, Sean P; Amin, Ripal; Homer, Craig R; McDonald, Christine; Cowman, Mary K; de la Motte, Carol A

2013-10-04

Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn.

THE EFFECTS OF DRONABINOL DURING DETOXIFICATION AND THE INITIATION OF TREATMENT WITH EXTENDED RELEASE NALTREXONE

PubMed Central

Bisaga, Adam; Sullivan, Maria A.; Glass, Andrew; Mishlen, Kaitlyn; Pavlicova, Martina; Haney, Margaret; Raby, Wilfrid N.; Levin, Frances R.; Carpenter, Kenneth M.; Mariani, John J.; Nunes, Edward V.

2015-01-01

Background Evidence suggests that the cannabinoid system is involved in the maintenance of opioid dependence. We examined whether dronabinol, a cannabinoid receptor type 1 partial agonist, reduces opioid withdrawal and increases retention in treatment with extended release naltrexone (XR-naltrexone). Methods Opioid dependent participants were randomized to receive dronabinol 30 mg/d (n=40) or placebo (n=20), under double-blind conditions, while they underwent inpatient detoxification and naltrexone induction. Before discharge all participants received an injection of XR-naltrexone, with an additional dose given four weeks later. Dronabinol or placebo was given while inpatient and for 5 weeks afterwards. The primary outcomes were the severity of opioid withdrawal, measured with the Subjective Opioid Withdrawal Scale, and retention in treatment at the end of the inpatient phase and at the end of the 8-week trial. Results The severity of opioid withdrawal during inpatient phase was lower in the dronabinol group relative to placebo group (p=0.006). Rates of successful induction onto XR-naltrexone (dronabinol 66%, placebo 55%) and completion of treatment (dronabinol 35%, placebo 35%) were not significantly different. Post-hoc analysis showed that the 32% of participants who smoked marijuana regularly during the outpatient phase had significantly lower ratings of insomnia and anxiety and were more likely to complete the 8-week trial. Conclusion Dronabinol reduced the severity of opiate withdrawal during acute detoxification but had no effect on rates of XR-naltrexone treatment induction and retention. Participants who elected to smoke marijuana during the trial were more likely to complete treatment regardless of treatment group assignment. PMID:26187456

Involvement of JNK and NF-κB pathways in lipopolysaccharide (LPS)-induced BAG3 expression in human monocytic cells.

PubMed

Wang, Hua-Qin; Meng, Xin; Liu, Bao-Qin; Li, Chao; Gao, Yan-Yan; Niu, Xiao-Fang; Li, Ning; Guan, Yifu; Du, Zhen-Xian

2012-01-01

Lipopolysaccharide (LPS) is an outer-membrane glycolipid component of Gram-negative bacteria known for its fervent ability to activate monocytic cells and for its potent proinflammatory capabilities. Bcl-2-associated athanogene 3 (BAG3) is a survival protein that has been shown to be stimulated during cell response to stressful conditions, such as exposure to high temperature, heavy metals, proteasome inhibition, and human immunodeficiency virus 1 (HIV-1) infection. In addition, BAG3 regulates replication of Varicella-Zoster Virus (VZV) and Herpes Simplex Virus (HSV) replication, suggesting that BAG3 could participate in the host response to infection. In the current study, we found that LPS increased the expression of BAG3 in a dose- and time-dependent manner. Actinomycin D completely blocked the LPS-induced BAG3 accumulation, as well as LPS activated the proximal promoter of BAG3 gene, supported that the induction by LPS occurred at the level of gene transcription. LPS-induced BAG3 expression was blocked by JNK or NF-κB inhibition, suggesting that JNK and NF-κB pathways participated in BAG3 induction by LPS. In addition, we also found that induction of BAG3 was implicated in monocytic cell adhesion to extracellular matrix induced by LPS. Overall, the data support that BAG3 is induced by LPS via JNK and NF-κB-dependent signals, and involved in monocytic cell-extracellular matrix interaction, suggesting that BAG3 may have a role in the host response to LPS stimulation. Copyright © 2011 Elsevier Inc. All rights reserved.

Human Milk Hyaluronan Enhances Innate Defense of the Intestinal Epithelium*

PubMed Central

Hill, David R.; Rho, Hyunjin K.; Kessler, Sean P.; Amin, Ripal; Homer, Craig R.; McDonald, Christine; Cowman, Mary K.; de la Motte, Carol A.

2013-01-01

Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn. PMID:23950179

Dose rate effect on micronuclei induction in human blood lymphocytes exposed to single pulse and multiple pulses of electrons.

PubMed

Acharya, Santhosh; Bhat, N N; Joseph, Praveen; Sanjeev, Ganesh; Sreedevi, B; Narayana, Y

2011-05-01

The effects of single pulses and multiple pulses of 7 MV electrons on micronuclei (MN) induction in cytokinesis-blocked human peripheral blood lymphocytes (PBLs) were investigated over a wide range of dose rates per pulse (instantaneous dose rate). PBLs were exposed to graded doses of 2, 3, 4, 6, and 8 Gy of single electron pulses of varying pulse widths at different dose rates per pulse, ranging from 1 × 10(6) Gy s(-1) to 3.2 × 10(8) Gy s(-1). Different dose rates per pulse were achieved by changing the dose per electron pulse by adjusting the beam current and pulse width. MN yields per unit absorbed dose after irradiation with single electron pulses were compared with those of multiple pulses of electrons. A significant decrease in the MN yield with increasing dose rates per pulse was observed, when dose was delivered by a single electron pulse. However, no reduction in the MN yield was observed when dose was delivered by multiple pulses of electrons. The decrease in the yield at high dose rates per pulse suggests possible radical recombination, which leads to decreased biological damage. Cellular response to the presence of very large numbers of chromosomal breaks may also alter the damage.

Induction and repair of DNA strand breaks in bovine lens epithelial cells after high LET irradiation

NASA Astrophysics Data System (ADS)

Baumstark-Khan, C.; Heilmann, J.; Rink, H.

The lens epithelium is the initiation site for the development of radiation induced cataracts. Radiation in the cortex and nucleus interacts with proteins, while in the epithelium, experimental results reveal mutagenic and cytotoxic effects. It is suggested that incorrectly repaired DNA damage may be lethal in terms of cellular reproduction and also may initiate the development of mutations or transformations in surviving cells. The occurrence of such genetically modified cells may lead to lens opacification. For a quantitative risk estimation for astronauts and space travelers it is necessary to know the relative biological effectiveness (RBE), because the spacial and temporal distribution of initial physical damage induced by cosmic radiation differ significantly from that of X-rays. RBEs for the induction of DNA strand breaks and the efficiency of repair of these breaks were measured in cultured diploid bovine lens epithelial cells exposed to different LET irradiation to either 300 kV X-rays or to heavy ions at the UNILAC accelerator at GSI. Accelerated ions from Z=8 (O) to Z=92 (U) were used. Strand breaks were measured by hydroxyapatite chromatography of alkaline unwound DNA (overall strand breaks). Results showed that DNA damage occurs as a function of dose, of kinetic energy and of LET. For particles having the same LET the severity of the DNA damage increases with dose. For a given particle dose, as the LET rises, the numbers of DNA strand breaks increase to a maximum and then reach a plateau or decrease. Repair kinetics depend on the fluence (irradiation dose). At any LET value, repair is much slower after heavy ion exposure than after X-irradiation. For ions with an LET of less than 10,000 keV μ -1 more than 90 percent of the strand breaks induced are repaired within 24 hours. At higher particle fluences, especially for low energetic particles with a very high local density of energy deposition within the particle track, a higher proportion of non-rejoined breaks is found, even after prolonged periods of incubation. At the highest LET value (16,300 keV μ -1 no significant repair is observed. These LET-dependencies are consistent with the current mechanistic model for radiation induced cataractogenesis which postulates that genomic damage to the surviving fraction of epithelial cells is responsible for lens opacification.

Human colon cancer HT-29 cell death responses to doxorubicin and Morus Alba leaves flavonoid extract.

PubMed

Fallah, S; Karimi, A; Panahi, G; Gerayesh Nejad, S; Fadaei, R; Seifi, M

2016-03-31

The mechanistic basis for the biological properties of Morus alba flavonoid extract (MFE) and chemotherapy drug of doxorubicin on human colon cancer HT-29 cell line death are unknown. The effect of doxorubicin and flavonoid extract on colon cancer HT-29 cell line death and identification of APC gene expression and PARP concentration of HT-29 cell line were investigated. The results showed that flavonoid extract and doxorubicin induce a dose dependent cell death in HT-29 cell line. MFE and doxorubicin exert a cytotoxic effect on human colon cancer HT-29 cell line by probably promoting or induction of apoptosis.

Probiotics and down-regulation of the allergic response.

PubMed

Kalliomäki, Marko A; Isolauri, Erika

2004-11-01

The first clinical trials with probiotics, especially in the treatment of atopic eczema, have yielded encouraging results. Experimental studies have found that probiotics exert strain-specific effects in the intestinal lumen and on epithelial cells and immune cells with anti-allergic potential. These effects include enhancement in antigen degradation and gut barrier function and induction of regulatory and proinflammatory immune responses, the latter of which occurs more likely beyond the intestinal epithelium. Future studies should address more accurately how these and other possible mechanisms operate in the complex gastrointestinal macroenvironment in vivo and how these mechanisms are related to the clinical effects in a dose-dependent manner.

Micronucleus formation induced by dielectric barrier discharge plasma exposure in brain cancer cells

NASA Astrophysics Data System (ADS)

Kaushik, Nagendra K.; Uhm, Hansup; Ha Choi, Eun

2012-02-01

Induction of micronucleus formation (cytogenetic damage) in brain cancer cells upon exposure of dielectric barrier discharge plasma has been investigated. We have investigated the influence of exposure and incubation times on T98G brain cancer cells by using growth kinetic, clonogenic, and micronucleus formation assay. We found that micronucleus formation rate directly depends on the plasma exposure time. It is also shown that colony formation capacity of cells has been inhibited by the treatment of plasma at all doses. Cell death and micronucleus formation are shown to be significantly elevated by 120 and 240 s exposure of dielectric barrier discharge plasma.

21 CFR 522.2005 - Propofol injection.

Code of Federal Regulations, 2010 CFR

2010-04-01

... indicated for use as an anesthetic as follows: As a single injection to provide general anesthesia for procedures lasting up to 5 minutes; for induction and maintenance of general anesthesia using incremental doses to effect; for induction of general anesthesia where maintenance is provided by inhalant...

Transcriptomic profile of host response in mouse brain after exposure to plant toxin abrin.

PubMed

Bhaskar, A S Bala; Gupta, Nimesh; Rao, P V Lakshmana

2012-09-04

Abrin toxin is a plant glycoprotein, which is similar in structure and properties to ricin and is obtained from the seeds of Abrus precatorius (jequirity bean). Abrin is highly toxic, with an estimated human fatal dose of 0.1-1 μg/kg, and has caused death after accidental and intentional poisoning. Abrin is a potent biological toxin warfare agent. There are no chemical antidotes available against the toxin. Neurological symptoms like delirium, hallucinations, reduced consciousness and generalized seizures were reported in human poisoning cases. Death of a patient with symptoms of acute demyelinating encephalopathy with gastrointestinal bleeding due to ingestion of abrin seeds was reported in India. The aim of this study was to examine both dose and time-dependent transcriptional responses induced by abrin in the adult mouse brain. Mice (n=6) were exposed to 1 and 2 LD50 (2.83 and 5.66 μg/kg respectively) dose of abrin by intraperitoneal route and observed over 3 days. A subset of animals (n=3) were sacrificed at 1 and 2 day intervals for microarray and histopathology analysis. None of the 2 LD50 exposed animals survived till 3 days. The histopathological analysis showed the severe damage in brain and the infiltration of inflammatory cells in a dose and time dependent manner. The abrin exposure resulted in the induction of rapid immune and inflammatory response in brain. Clinical biochemistry parameters like lactate dehydrogenase, aspartate aminotransferase, urea and creatinine showed significant increase at 2-day 2 LD50 exposure. The whole genome microarray data revealed the significant regulation of various pathways like MAPK pathway, cytokine-cytokine receptor interaction, calcium signaling pathway, Jak-STAT signaling pathway and natural killer cell mediated toxicity. The comparison of differential gene expression at both the doses showed dose dependent effects of abrin toxicity. The real-time qRT-PCR analysis of selected genes supported the microarray data. This is the first report on host-gene response using whole genome microarray in an animal model after abrin exposure. The data generated provides leads for developing suitable medical counter measures against abrin poisoning. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Low-dose fotemustine as second-line chemotherapy for recurrent glioblastoma multiforme.

PubMed

De Felice, Francesca; Bulzonetti, Nadia; Musio, Daniela; D'Elia, Alessandro; Salvati, Maurizio; Tombolini, Vincenzo

2013-09-01

To test if fotemustine administrated at low doses during the maintenance phase of gioblastoma therapy could improve the toxicity profile, without reducing progression-free survival at six months (PFS-6). Patients enrolled were affected by recurrent glioblastoma multiforme, proven by magnetic resonance imaging (MRI), at least six months after radiochemotherapy completion. Fotemustine was administered at an induction dose of 100 mg/m(2) followed by a maintenance dose of 75 mg/m(2). All 15 patients completed the induction phase. Eight patients began maintenance-phase therapy and received a median of three cycles (range=2-6). Grade 3 or more haematological toxicity was not documented. The PFS-6 was 5/15 and the median overall survival was 7.5 months. Haematological toxicity compares favourably with trials using the conventional scheme: no grade 3-4 adverse effects were recorded. This low-dose approach could be considered a compromise treatment whilst waiting for definitive standardization of second-line therapy, in order to reduce severe hematological toxicity.

Time-Dependent Effects of Localized Inflammation on Peripheral Clock Gene Expression in Rats

PubMed Central

Westfall, Susan; Aguilar-Valles, Argel; Mongrain, Valérie; Luheshi, Giamal N.; Cermakian, Nicolas

2013-01-01

Many aspects of the immune system, including circulating cytokine levels as well as counts and function of various immune cell types, present circadian rhythms. Notably, the mortality rate of animals subjected to high doses of lipopolysaccharide is dependent on the time of treatment. In addition, the severity of symptoms of various inflammatory conditions follows a daily rhythmic pattern. The mechanisms behind the crosstalk between the circadian and immune systems remain elusive. Here we demonstrate that localized inflammation induced by turpentine oil (TURP) causes a time-dependent induction of interleukin (IL)-6 and has time-, gene- and tissue-specific effects on clock gene expression. More precisely, TURP blunts the peak of Per1 and Per2 expression in the liver while in other tissues, the expression nadir is elevated. In contrast, Rev-erbα expression remains relatively unaffected by TURP treatment. Co-treatment with the anti-inflammatory agent IL-1 receptor antagonist (IL-1Ra) did not alter the response of Per2 to TURP treatment in liver, despite the reduced induction of fever and IL-6 serum levels. This indicates that the TURP-mediated changes of Per2 in the liver might be due to factors other than systemic IL-6 and fever. Accordingly, IL-6 treatment had no effect on clock gene expression in HepG2 liver carcinoma cells. Altogether, we show that localized inflammation causes significant time-dependent changes in peripheral circadian clock gene expression, via a mechanism likely involving mediators independent from IL-6 and fever. PMID:23527270

Effects of tumor necrosis factor-alpha and interferon-gamma on expressions of matrix metalloproteinase-2 and -9 in human bladder cancer cells.

PubMed

Shin, K Y; Moon, H S; Park, H Y; Lee, T Y; Woo, Y N; Kim, H J; Lee, S J; Kong, G

2000-10-31

We have investigated the effects of tumor necrosis factor-alpha (TNF-alpha) and interferon (INF-gamma), the potent Bacillus Calmette-Guerin (BCG)-induced cytokines on the production of MMP-2, MMP-9, TIMP-1, TIMP-2 and MT1-MMP in high grade human bladder cancer cell lines, T-24, J-82 and HT-1376 cell lines. MMP-2 expression and activity were decreased in T-24 cells treated with both cytokines in a dose dependent manner. However, J-82 cells treated with TNF-alpha and INF-gamma revealed dose dependent increases of MMP-9 expression and activity with similar baseline expression and activity of MMP-2. HT-1376 cells after exposure to TNF-alpha only enhanced the expression and activity of MMP-9. These results indicate that TNF-alpha and INF-gamma could regulate the production of MMP-2 or MMP-9 on bladder cancer cells and their patterns of regulation are cell specific. Furthermore, this diverse response of bladder cancer cells to TNF-alpha and INF-gamma suggests that BCG immunotherapy may enhance the invasiveness of bladder cancer in certain conditions with induction of MMPs.

Crocidolite asbestos causes an induction of p53 and apoptosis in cultured A-549 lung carcinoma cells.

PubMed

Pääkkö, P; Rämet, M; Vähäkangas, K; Korpela, N; Soini, Y; Turunen, S; Jaworska, M; Gillissen, A

1998-01-01

A number of genotoxic chemicals and agents, such as benzo(a)pyrene and ultraviolet light, are able to induce nuclear accumulation of p53 protein. Usually, this response is transient and a consequence of stabilization of the wild-type p53 protein. After withdrawal of the exposure, the amount of p53 protein returns to a normal level within hours or a few days. We have studied the p53 response to the exposure of crocidolite asbestos in A-549 lung carcinoma cells using three different methods, i.e., p53 immunohistochemistry, Western blotting and metabolic labelling followed by p53 immunoprecipitation. With these techniques we demonstrate a dose-dependent p53 nuclear response to crocidolite exposure. The half-life of p53 protein in A-549 lung carcinoma cells cultured in serum-free media increased from 30 up to 80 min, and the protein reacted with a wild-type specific antibody suggesting that it was in a wild-type conformation. In situ 3'-end labelling of A-549 cells demonstrated a dose-dependent increase in apoptotic activity. Our data support the idea that increased apoptotic activity, induced by crocidolite, is mediated by p53.

Chlorinated river and lake water extract caused oxidative damage, DNA migration and cytotoxicity in human cells.

PubMed

Yuan, Jing; Wu, Xin-Jiang; Lu, Wen-Qing; Cheng, Xiao-Li; Chen, Dan; Li, Xiao-Yan; Liu, Ai-Lin; Wu, Jian-Jun; Xie, Hong; Stahl, Thorsten; Mersch-Sundermann, Volker

2005-01-01

Consumption of chlorinated drinking water is suspected to be associated with adverse health effects, including mutations and cancer. In the present study, the genotoxic potential of water from Donghu lake, Yangtze river and Hanjiang river in Wuhan, an 8-million metropolis in China, was investigated using HepG2 cells and the alkaline version of the comet assay. It could be shown that all water extracts caused dose-dependent DNA migration in concentrations corresponding to dried extracts of 0.167-167 ml chlorinated drinking water per ml medium. To explore whether the intracellular redox status is regulated by chlorinated drinking water, we determined lipid peroxidation (LPO) and depletion of reduced glutathione (GSH). The malondialdehyde (thiobarbituric acid (TBA)-reactive aldehydes) concentration increased after chlorinated drinking water treatment of HepG2 cells in a dose-dependent manner, the GSH content decreased. The activity of lactate dehydrogenase (LDH) increased in chlorinated drinking water treated HepG2 cells indicating cytotoxicity. In accordance with former studies which dealt with in vivo and in vitro micronucleus induction the present study shows that chlorinated drinking water from polluted raw water may entail genetic risks.

Total triterpenoids from Ganoderma Lucidum suppresses prostate cancer cell growth by inducing growth arrest and apoptosis.

PubMed

Wang, Tao; Xie, Zi-ping; Huang, Zhan-sen; Li, Hao; Wei, An-yang; Di, Jin-ming; Xiao, Heng-jun; Zhang, Zhi-gang; Cai, Liu-hong; Tao, Xin; Qi, Tao; Chen, Di-ling; Chen, Jun

2015-10-01

In this study, one immortalized human normal prostatic epithelial cell line (BPH) and four human prostate cancer cell lines (LNCaP, 22Rv1, PC-3, and DU-145) were treated with Ganoderma Lucidum triterpenoids (GLT) at different doses and for different time periods. Cell viability, apoptosis, and cell cycle were analyzed using flow cytometry and chemical assays. Gene expression and binding to DNA were assessed using real-time PCR and Western blotting. It was found that GLT dose-dependently inhibited prostate cancer cell growth through induction of apoptosis and cell cycle arrest at G1 phase. GLT-induced apoptosis was due to activation of Caspases-9 and -3 and turning on the downstream apoptotic events. GLT-induced cell cycle arrest (mainly G1 arrest) was due to up-regulation of p21 expression at the early time and down-regulation of cyclin-dependent kinase 4 (CDK4) and E2F1 expression at the late time. These findings demonstrate that GLT suppresses prostate cancer cell growth by inducing growth arrest and apoptosis, which might suggest that GLT or Ganoderma Lucidum could be used as a potential therapeutic drug for prostate cancer.

Cytotoxicity and Genotoxicity of Cypermethrin in Hepatocarcinoma Cells: A Dose- and Time-Dependent Study

PubMed Central

AlKahtane, Abdullah A.; Alarifi, Saud; Al-Qahtani, Ahmed A.; Ali, Daoud; Alomar, Suliman Y.; Aleissia, Mohammed S.; Alkahtani, Saad

2018-01-01

Most of the agricultural workers are potentially exposed to pesticides through different routes. Inhalation exposures may result in numerous diseases that can adversely affect an individual’s health and capacity to perform at work. The aim of this study was to determine the cytotoxic potential of cypermethrin pesticide on cultured human hepatocarcinoma (HepG2) cells. The HepG2 cells were exposed to cypermethrin (0, 5, 15, 40 ng/mL) for 24 and 48 hours. We observed that cypermethrin caused cell death of HepG2 cells using 3-(4, 5-dimethylthiozolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase tests. Furthermore, cypermethrin reduced HepG2 cells viability in a time and dose dependent basis, that was probably mediated through the induction of reactive oxygen species (ROS) and apoptosis. An increase in ROS generation with a concomitant increase in expression of the proapoptotic protein Bcl-2 and cytochrome c and decrease in the antiapoptosis protein Bax suggested that a mitochondria-mediated pathway was involved in cypermethrin-induced apoptosis. These findings provide insights into the underlying mechanisms involved in cytotoxicity of cypermethrin in HepG2 cells. PMID:29686591

The inhibitory effect of disulfiram encapsulated PLGA NPs on tumor growth: Different administration routes.

PubMed

Fasehee, Hamidreza; Zarrinrad, Ghazaleh; Tavangar, Seyed Mohammad; Ghaffari, Seyed Hamidollah; Faghihi, Shahab

2016-06-01

The strong anticancer activity of disulfiram is hindered by its rapid degradation in blood system. A novel folate-receptor-targeted poly (lactide-co-glycolide) (PLGA)-polyethylene glycol (PEG) nanoparticle (NP) is developed for encapsulation and delivery of disulfiram into breast cancer tumor using passive (EPR effect) and active (folate receptor) targeting. The anticancer activity of disulfiram and its effect on caspase-3 activity and cell cycle are studied. The administration of encapsulated PLGA NPs using intra-peritoneal, intravenous and intra-tumor routes is investigated using animal model. Disulfiram shows strong cytotoxicity against MCF7 cell line. The activity of caspase-3 inhibited with disulfiram via dose dependent manner while the drug causes cell cycle arrest in G0/G1 and S phase time-dependently. The encapsulated disulfiram shows higher activity in apoptosis induction as compared to free drug. In nontoxic dose of encapsulated disulfiram, the highest and lowest efficacy of NPs in tumor growth inhibition is observed for intravenous injection and intraperitoneal injection. It is suggested that administration of disulfiram by targeted PLGA nanoparticles using intravenous injection would present an alternative therapeutic approach for solid tumor treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

Cytotoxicity and Genotoxicity of Cypermethrin in Hepatocarcinoma Cells: A Dose- and Time-Dependent Study.

PubMed

AlKahtane, Abdullah A; Alarifi, Saud; Al-Qahtani, Ahmed A; Ali, Daoud; Alomar, Suliman Y; Aleissia, Mohammed S; Alkahtani, Saad

2018-01-01

Most of the agricultural workers are potentially exposed to pesticides through different routes. Inhalation exposures may result in numerous diseases that can adversely affect an individual's health and capacity to perform at work. The aim of this study was to determine the cytotoxic potential of cypermethrin pesticide on cultured human hepatocarcinoma (HepG2) cells. The HepG2 cells were exposed to cypermethrin (0, 5, 15, 40 ng/mL) for 24 and 48 hours. We observed that cypermethrin caused cell death of HepG2 cells using 3-(4, 5-dimethylthiozolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase tests. Furthermore, cypermethrin reduced HepG2 cells viability in a time and dose dependent basis, that was probably mediated through the induction of reactive oxygen species (ROS) and apoptosis. An increase in ROS generation with a concomitant increase in expression of the proapoptotic protein Bcl-2 and cytochrome c and decrease in the antiapoptosis protein Bax suggested that a mitochondria-mediated pathway was involved in cypermethrin-induced apoptosis. These findings provide insights into the underlying mechanisms involved in cytotoxicity of cypermethrin in HepG2 cells.

Chronic low-dose ultraviolet-induced mutagenesis in nucleotide excision repair-deficient cells.

PubMed

Haruta, Nami; Kubota, Yoshino; Hishida, Takashi

2012-09-01

UV radiation induces two major types of DNA lesions, cyclobutane pyrimidine dimers (CPDs) and 6-4 pyrimidine-pyrimidine photoproducts, which are both primarily repaired by nucleotide excision repair (NER). Here, we investigated how chronic low-dose UV (CLUV)-induced mutagenesis occurs in rad14Δ NER-deficient yeast cells, which lack the yeast orthologue of human xeroderma pigmentosum A (XPA). The results show that rad14Δ cells have a marked increase in CLUV-induced mutations, most of which are C→T transitions in the template strand for transcription. Unexpectedly, many of the CLUV-induced C→T mutations in rad14Δ cells are dependent on translesion synthesis (TLS) DNA polymerase η, encoded by RAD30, despite its previously established role in error-free TLS. Furthermore, we demonstrate that deamination of cytosine-containing CPDs contributes to CLUV-induced mutagenesis. Taken together, these results uncover a novel role for Polη in the induction of C→T transitions through deamination of cytosine-containing CPDs in CLUV-exposed NER deficient cells. More generally, our data suggest that Polη can act as both an error-free and a mutagenic DNA polymerase, depending on whether the NER pathway is available to efficiently repair damaged templates.

Perioperative pharmacokinetics of methadone in adolescents.

PubMed

Sharma, Anshuman; Tallchief, Danielle; Blood, Jane; Kim, Thomas; London, Amy; Kharasch, Evan D

2011-12-01

Methadone is frequently administered to adults experiencing anesthesia and receiving pain treatment. Methadone pharmacokinetics in adults are well characterized, including the perioperative period. Methadone is also used in children. There is, however, no information on methadone pharmacokinetics in children of any age. The purpose of this investigation was to determine the pharmacokinetics of intravenous methadone in children undergoing surgery. Perioperative opioid-sparing effects were also assessed. Eligible subjects were children 5-18 yr undergoing general anesthesia and surgery, with an anticipated postoperative inpatient stay exceeding 3 days. Three groups of 10 to 11 patients each received intravenous methadone hydrochloride after anesthetic induction in ascending dose groups of 0.1, 0.2, and 0.3 mg/kg (up to 20 mg). Anesthetic care was not otherwise changed. Venous blood was obtained for 4 days, for stereoselective determination of methadone and metabolites. Pain assessments were made each morning. Daily and total opioid consumption was determined. Perioperative opioid consumption and pain was determined in a second cohort, which was matched to age, sex, race, ethnicity, surgical procedure, and length of stay, but not receiving methadone. The final methadone study cohort was 31 adolescents (14 ± 2 yr, range 10-18) undergoing major spine surgery for a diagnosis of scoliosis. Methadone pharmacokinetics were linear over the dose range 0.1-0.3 mg/kg. Disposition was stereoselective. Methadone administration did not dose-dependently affect postoperative pain scores, and did not dose-dependently decrease daily or total postoperative opioid consumption in spinal fusion patients. Methadone enantiomer disposition in adolescents undergoing surgery was similar to that in healthy adults.

Low-dose gonadotropin induction of ovulation in anovulatory women - still needed in the age of IVF.

PubMed

White, Davinia; Hardy, Kate; Lovelock, Suzannah; Franks, Stephen

2018-02-19

Low-dose, step-up gonadotropin is the treatment of choice for women with PCOS who have not conceived after anti-estrogen treatment, and as an effective alternative to pulsatile GnRH in women with hypogonadotropic hypogonadism (HH). There has been, however, no large-scale, comparative study between the two groups using low-dose gonadotropins. Here we performed a retrospective, comparative analysis, in a single clinic database, of efficacy and safety of induction of ovulation using low-dose gonadotropins in 364 Women with PCOS and 80 women with HH. The rate of ovulation was high in both PCOS (83%) and HH (84%) but mono-follicular, ovulatory cycles were more prevalent in PCOS than in HH (77% vs 53%, p<0.0001) and the proportion of cycles that were abandoned was higher in HH than in PCOS (25% vs 15%, p<0.0001). The median threshold dose of gonadotropin required to induce ovulation was 75iu/day in PCOS and 113iu/day in HH (p<0.001) and the range of doses was greater in HH women. Forty-nine percent of women with PCOS and 65% of those with HH conceived (more than 90% within 6 cycles of treatment) and had a least one pregnancy. Multiple pregnancies (all twins) occurred in only 4% of women with PCOS and 5% of those with HH. These findings emphasise the efficacy and safety of low-dose gonadotropin treatment for both clomiphene-resistant women with PCOS and those with HH. These results highlight the importance of choosing the more physiological approach of gonadotropin induction of ovulation in both groups as the most appropriate treatment, in preference to IVF.

Inducible DNA-repair systems in yeast: competition for lesions.

PubMed

Mitchel, R E; Morrison, D P

1987-03-01

DNA lesions may be recognized and repaired by more than one DNA-repair process. If two repair systems with different error frequencies have overlapping lesion specificity and one or both is inducible, the resulting variable competition for the lesions can change the biological consequences of these lesions. This concept was demonstrated by observing mutation in yeast cells (Saccharomyces cerevisiae) exposed to combinations of mutagens under conditions which influenced the induction of error-free recombinational repair or error-prone repair. Total mutation frequency was reduced in a manner proportional to the dose of 60Co-gamma- or 254 nm UV radiation delivered prior to or subsequent to an MNNG exposure. Suppression was greater per unit radiation dose in cells gamma-irradiated in O2 as compared to N2. A rad3 (excision-repair) mutant gave results similar to wild-type but mutation in a rad52 (rec-) mutant exposed to MNNG was not suppressed by radiation. Protein-synthesis inhibition with heat shock or cycloheximide indicated that it was the mutation due to MNNG and not that due to radiation which had changed. These results indicate that MNNG lesions are recognized by both the recombinational repair system and the inducible error-prone system, but that gamma-radiation induction of error-free recombinational repair resulted in increased competition for the lesions, thereby reducing mutation. Similarly, gamma-radiation exposure resulted in a radiation dose-dependent reduction in mutation due to MNU, EMS, ENU and 8-MOP + UVA, but no reduction in mutation due to MMS. These results suggest that the number of mutational MMS lesions recognizable by the recombinational repair system must be very small relative to those produced by the other agents. MNNG induction of the inducible error-prone systems however, did not alter mutation frequencies due to ENU or MMS exposure but, in contrast to radiation, increased the mutagenic effectiveness of EMS. These experiments demonstrate that in this lower eukaryote, mutagen exposure does not necessarily result in a fixed risk of mutation, but that the risk can be markedly influenced by a variety of external stimuli including heat shock or exposure to other mutagens.

Dexamethasone and High-Dose Methotrexate Improve Outcome for Children and Young Adults With High-Risk B-Acute Lymphoblastic Leukemia: A Report From Children’s Oncology Group Study AALL0232

PubMed Central

Devidas, Meenakshi; Chen, Si; Salzer, Wanda L.; Raetz, Elizabeth A.; Loh, Mignon L.; Mattano, Leonard A.; Cole, Catherine; Eicher, Alisa; Haugan, Maureen; Sorenson, Mark; Heerema, Nyla A.; Carroll, Andrew A.; Gastier-Foster, Julie M.; Borowitz, Michael J.; Wood, Brent L.; Willman, Cheryl L.; Winick, Naomi J.; Hunger, Stephen P.; Carroll, William L.

2016-01-01

Purpose Survival for children and young adults with high-risk B-acute lymphoblastic leukemia has improved significantly, but 20% to 25% of patients are not cured. Children’s Oncology Group study AALL0232 tested two interventions to improve survival. Patients and Methods Between January 2004 and January 2011, AALL0232 enrolled 3,154 participants 1 to 30 years old with newly diagnosed high-risk B-acute lymphoblastic leukemia. By using a 2 × 2 factorial design, 2,914 participants were randomly assigned to receive dexamethasone (14 days) versus prednisone (28 days) during induction and high-dose methotrexate versus Capizzi escalating-dose methotrexate plus pegaspargase during interim maintenance 1. Results Planned interim monitoring showed the superiority of the high-dose methotrexate regimens, which exceeded the predefined boundary and led to cessation of enrollment in January 2011. At that time, participants randomly assigned to high-dose methotrexate during interim maintenance 1 versus those randomly assigned to Capizzi methotrexate had a 5-year event-free survival (EFS) of 82% versus 75.4% (P = .006). Mature final data showed 5-year EFS rates of 79.6% for high-dose methotrexate and 75.2% for Capizzi methotrexate (P = .008). High-dose methotrexate decreased both marrow and CNS recurrences. Patients 1 to 9 years old who received dexamethasone and high-dose methotrexate had a superior outcome compared with those who received the other three regimens (5-year EFS, 91.2% v 83.2%, 80.8%, and 82.1%; P = .015). Older participants derived no benefit from dexamethasone during induction and experienced excess rates of osteonecrosis. Conclusion High-dose methotrexate is superior to Capizzi methotrexate for the treatment of high-risk B-acute lymphoblastic leukemia, with no increase in acute toxicity. Dexamethasone given during induction benefited younger children but provided no benefit and was associated with a higher risk of osteonecrosis among participants 10 years and older. PMID:27114587

Focal Radiation Therapy Dose Escalation Improves Overall Survival in Locally Advanced Pancreatic Cancer Patients Receiving Induction Chemotherapy and Consolidative Chemoradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishnan, Sunil, E-mail: skrishnan@mdanderson.org; Chadha, Awalpreet S.; Suh, Yelin

2016-03-15

Purpose: To review outcomes of locally advanced pancreatic cancer (LAPC) patients treated with dose-escalated intensity modulated radiation therapy (IMRT) with curative intent. Methods and Materials: A total of 200 patients with LAPC were treated with induction chemotherapy followed by chemoradiation between 2006 and 2014. Of these, 47 (24%) having tumors >1 cm from the luminal organs were selected for dose-escalated IMRT (biologically effective dose [BED] >70 Gy) using a simultaneous integrated boost technique, inspiration breath hold, and computed tomographic image guidance. Fractionation was optimized for coverage of gross tumor and luminal organ sparing. A 2- to 5-mm margin around the gross tumor volume wasmore » treated using a simultaneous integrated boost with a microscopic dose. Overall survival (OS), recurrence-free survival (RFS), local-regional and distant RFS, and time to local-regional and distant recurrence, calculated from start of chemoradiation, were the outcomes of interest. Results: Median radiation dose was 50.4 Gy (BED = 59.47 Gy) with a concurrent capecitabine-based (86%) regimen. Patients who received BED >70 Gy had a superior OS (17.8 vs 15.0 months, P=.03), which was preserved throughout the follow-up period, with estimated OS rates at 2 years of 36% versus 19% and at 3 years of 31% versus 9% along with improved local-regional RFS (10.2 vs 6.2 months, P=.05) as compared with those receiving BED ≤70 Gy. Degree of gross tumor volume coverage did not seem to affect outcomes. No additional toxicity was observed in the high-dose group. Higher dose (BED) was the only predictor of improved OS on multivariate analysis. Conclusion: Radiation dose escalation during consolidative chemoradiation therapy after induction chemotherapy for LAPC patients improves OS and local-regional RFS.« less

Influence of irradiation on the osteoinductive potential of demineralized bone matrix.

PubMed

Wientroub, S; Reddi, A H

1988-04-01

Samples of demineralized bone matrix (DBM) were exposed to graduated doses of radiation (1-15 Megarad) (Mrad) utilizing a linear accelerator and then implanted into the thoracic region of Long-Evans rats. Subcutaneous implantation of DBM into allogenic rats induces endochondral bone. In response to matrix implantation, a cascade of events ensues; mesenchymal cell proliferation on day 3 postimplantation, chondrogenesis on day 7, calcification of the cartilagenous matrix and chondrolysis on day 9, and osteogenesis on day 11 resulting in formation of an ossicle containing active hemopoietic tissue. Bone formation was assessed by measuring alkaline phosphatase activity, the rate of mineralization was determined by measuring 45Ca incorporation to bone mineral, and 40Ca content measured the extent of mineralization; acid phosphatase activity was used as a parameter for bone resorption. The dose of radiation (2.5 Mrad) currently used by bone banks for sterilization of bone tissue did not destroy the bone induction properties of DBM. Furthermore, radiation of 3-5 Mrad even enhanced bone induction, insofar as it produced more bone at the same interval of time than was obtained from unirradiated control samples. None of the radiation doses used in these experiments abolished bone induction, although the response induced by matrix irradiated with doses higher than 5 Mrad was delayed.

Rac1 Protein Signaling Is Required for DNA Damage Response Stimulated by Topoisomerase II Poisons*

PubMed Central

Huelsenbeck, Stefanie C.; Schorr, Anne; Roos, Wynand P.; Huelsenbeck, Johannes; Henninger, Christian; Kaina, Bernd; Fritz, Gerhard

2012-01-01

To investigate the potency of the topoisomerase II (topo II) poisons doxorubicin and etoposide to stimulate the DNA damage response (DDR), S139 phosphorylation of histone H2AX (γH2AX) was analyzed using rat cardiomyoblast cells (H9c2). Etoposide caused a dose-dependent increase in the γH2AX level as shown by Western blotting. By contrast, the doxorubicin response was bell-shaped with high doses failing to increase H2AX phosphorylation. Identical results were obtained by immunohistochemical analysis of γH2AX focus formation, comet assay-based DNA strand break analysis, and measuring the formation of the topo II-DNA cleavable complex. At low dose, doxorubicin activated ataxia telangiectasia mutated (ATM) but not ATM and Rad3-related (ATR). Both the lipid-lowering drug lovastatin and the Rac1-specific inhibitor NSC23766 attenuated doxorubicin- and etoposide-stimulated H2AX phosphorylation, induction of DNA strand breaks, and topo II-DNA complex formation. Lovastatin and NSC23766 acted in an additive manner. They did not attenuate doxorubicin-induced increase in p-ATM and p-Chk2 levels. DDR stimulated by topo II poisons was partially blocked by inhibition of type I p21-associated kinases. DDR evoked by the topoisomerase I poison topotecan remained unaffected by lovastatin. The data show that the mechanisms involved in DDR stimulated by topo II poisons are agent-specific with anthracyclines lacking DDR-stimulating activity at high doses. Pharmacological inhibition of Rac1 signaling counteracts doxorubicin- and etoposide-stimulated DDR by disabling the formation of the topo II-DNA cleavable complex. Based on the data we suggest that Rac1-regulated mechanisms are required for DNA damage induction and subsequent activation of the DDR following treatment with topo II but not topo I poisons. PMID:23012366

Rac1 protein signaling is required for DNA damage response stimulated by topoisomerase II poisons.

PubMed

Huelsenbeck, Stefanie C; Schorr, Anne; Roos, Wynand P; Huelsenbeck, Johannes; Henninger, Christian; Kaina, Bernd; Fritz, Gerhard

2012-11-09

To investigate the potency of the topoisomerase II (topo II) poisons doxorubicin and etoposide to stimulate the DNA damage response (DDR), S139 phosphorylation of histone H2AX (γH2AX) was analyzed using rat cardiomyoblast cells (H9c2). Etoposide caused a dose-dependent increase in the γH2AX level as shown by Western blotting. By contrast, the doxorubicin response was bell-shaped with high doses failing to increase H2AX phosphorylation. Identical results were obtained by immunohistochemical analysis of γH2AX focus formation, comet assay-based DNA strand break analysis, and measuring the formation of the topo II-DNA cleavable complex. At low dose, doxorubicin activated ataxia telangiectasia mutated (ATM) but not ATM and Rad3-related (ATR). Both the lipid-lowering drug lovastatin and the Rac1-specific inhibitor NSC23766 attenuated doxorubicin- and etoposide-stimulated H2AX phosphorylation, induction of DNA strand breaks, and topo II-DNA complex formation. Lovastatin and NSC23766 acted in an additive manner. They did not attenuate doxorubicin-induced increase in p-ATM and p-Chk2 levels. DDR stimulated by topo II poisons was partially blocked by inhibition of type I p21-associated kinases. DDR evoked by the topoisomerase I poison topotecan remained unaffected by lovastatin. The data show that the mechanisms involved in DDR stimulated by topo II poisons are agent-specific with anthracyclines lacking DDR-stimulating activity at high doses. Pharmacological inhibition of Rac1 signaling counteracts doxorubicin- and etoposide-stimulated DDR by disabling the formation of the topo II-DNA cleavable complex. Based on the data we suggest that Rac1-regulated mechanisms are required for DNA damage induction and subsequent activation of the DDR following treatment with topo II but not topo I poisons.

Nandrolone and stanozolol upregulate aromatase expression and further increase IGF-I-dependent effects on MCF-7 breast cancer cell proliferation.

PubMed

Sirianni, Rosa; Capparelli, Claudia; Chimento, Adele; Panza, Salvatore; Catalano, Stefania; Lanzino, Marilena; Pezzi, Vincenzo; Andò, Sebastiano

2012-11-05

Several doping agents, such as anabolic androgenic steroids (AAS) and peptide hormones like insulin-like growth factor-I (IGF-I), are employed without considering the potential deleterious effects that they can cause. In addition, androgens are used in postmenopausal women as replacement therapy. However, there are no clear guidelines regarding the optimal therapeutic doses of androgens or long-term safety data. In this study we aimed to determine if two commonly used AAS, nandrolone and stanozolol, alone or in combination with IGF-I, could activate signaling involved in breast cancer cell proliferation. Using a human breast cancer cell line, MCF-7, as an experimental model we found that both nandrolone and stanozolol caused a dose-dependent induction of aromatase expression and, consequently, estradiol production. Moreover, when nandrolone and stanozolol were combined with IGF-I, higher induction in aromatase expression was observed. This increase involved phosphatidylinositol 3-kinase (PI3K)/AKT and phospholipase C (PLC)/protein kinase C (PKC), which are part of IGF-I transductional pathways. Specifically, both AAS were able to activate membrane rapid signaling involving IGF-I receptor, extracellular regulated protein kinases 1/2 (ERK1/2) and AKT, after binding to estrogen receptor (ER), as confirmed by the ability of the ER antagonist ICI182, 780 to block such activation. The estrogenic activity of nandrolone and stanozolol was further confirmed by their capacity to induce the expression of the ER-regulated gene, CCND1 encoding for the cell cycle regulator cyclin D1, which represents a key protein for the control of breast cancer cell proliferation. In fact, when nandrolone and stanozolol were combined with IGF-I, they increased cell proliferation to levels higher than those elicited by the single factors. Taken together these data clearly indicate that the use of high doses of AAS, as occurs in doping practice, may increase the risk of breast cancer. This potential risk is higher when AAS are used in association with IGF-I. To our knowledge this is the first report directly associating AAS with this type of cancer. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Inecalcitol, an analog of 1,25D₃, displays enhanced antitumor activity through the induction of apoptosis in a squamous cell carcinoma model system

PubMed Central

Ma, Yingyu; Yu, Wei-Dong; Hidalgo, Alejandro A.; Luo, Wei; Delansorne, Remi; Johnson, Candace S.; Trump, Donald L.

2013-01-01

Epidemiological data suggest an important role of vitamin D signaling in cancer development and progression, and experimental studies demonstrate that the active vitamin D metabolite 1α, 25-dihydroxyvitamin D₃ (1,25D₃) has broad spectrum antitumor activity. Hypercalcemia has often been suggested to limit the clinical application of these data. The 14-epi-analog of 1,25D₃, inecalcitol [19-nor-14-epi-23-yne-1,25-(OH)₂D₃; TX522], was developed to have superagonistic antitumor activities but low hypercalcemia potential. We examined the antitumor activity of inecalcitol and the underlying mechanisms in a murine squamous cell carcinoma (SCC) model system. In vitro, compared with 1,25D₃, inecalcitol showed enhanced vitamin D receptor (VDR)-mediated transcriptional activity. Inecalcitol suppressed SCC cell proliferation in a dose-dependent manner with an IC₅₀ value 30 times lower than that of 1,25D₃. Both inecalcitol and 1,25D₃ induced a comparable level of G₀/G₁ cell cycle arrest in SCC cells. The level of apoptosis induced by inecalcitol was markedly higher than that of 1,25D₃. Apoptosis was mediated through the activation of the caspase 8/10- caspase 3 pathway. Further, inecalcitol markedly inhibited the mRNA and protein expression of c-IAP1 and XIAP compared with 1,25D₃. In vivo, inecalcitol inhibits SCC tumor growth in a dose-dependent fashion. Notably, inecalcitol induced a significantly higher level of apoptosis in the SCC xenograft model. While in vitro inecalcitol demonstrates apparent enhanced VDR binding and antiproliferative effects compared to 1,25D₃, in vivo these advantages disappear; at doses of inecalcitol that have equivalent antitumor effects, similar hypercalcemia is seen. This may be explained by the pharmacokinetics of 1,25D₃ vs. inecalcitol and attributed to the much shorter serum half-life of inecalcitol.We show that inecalcitol has potent antitumor activity in the SCC model system, and this is associated with a strong induction of apoptosis. These findings support the further development of inecalcitol in cancer treatment. PMID:23388458

The Alternative Epac/cAMP Pathway and the MAPK Pathway Mediate hCG Induction of Leptin in Placental Cells

PubMed Central

Maymó, Julieta Lorena; Pérez Pérez, Antonio; Maskin, Bernardo; Dueñas, José Luis; Calvo, Juan Carlos; Sánchez Margalet, Víctor; Varone, Cecilia Laura

2012-01-01

Pleiotropic effects of leptin have been identified in reproduction and pregnancy, particularly in the placenta, where it works as an autocrine hormone. In this work, we demonstrated that human chorionic gonadotropin (hCG) added to JEG-3 cell line or to placental explants induces endogenous leptin expression. We also found that hCG increased cAMP intracellular levels in BeWo cells in a dose-dependent manner, stimulated cAMP response element (CRE) activity and the cotransfection with an expression plasmid of a dominant negative mutant of CREB caused a significant inhibition of hCG stimulation of leptin promoter activity. These results demonstrate that hCG indeed activates cAMP/PKA pathway, and that this pathway is involved in leptin expression. Nevertheless, we found leptin induction by hCG is dependent on cAMP levels. Treatment with (Bu)2cAMP in combination with low and non stimulatory hCG concentrations led to an increase in leptin expression, whereas stimulatory concentrations showed the opposite effect. We found that specific PKA inhibition by H89 caused a significant increase of hCG leptin induction, suggesting that probably high cAMP levels might inhibit hCG effect. It was found that hCG enhancement of leptin mRNA expression involved the MAPK pathway. In this work, we demonstrated that hCG leptin induction through the MAPK signaling pathway is inhibited by PKA. We observed that ERK1/2 phosphorylation increased when hCG treatment was combined with H89. In view of these results, the involvement of the alternative cAMP/Epac signaling pathway was studied. We observed that a cAMP analogue that specifically activates Epac (CPT-OMe) stimulated leptin expression by hCG. In addition, the overexpression of Epac and Rap1 proteins increased leptin promoter activity and enhanced hCG. In conclusion, we provide evidence suggesting that hCG induction of leptin gene expression in placenta is mediated not only by activation of the MAPK signaling pathway but also by the alternative cAMP/Epac signaling pathway. PMID:23056265

Radiobiological Effectiveness of Ultrashort Laser-Driven Electron Bunches: Micronucleus Frequency, Telomere Shortening and Cell Viability.

PubMed

Andreassi, Maria Grazia; Borghini, Andrea; Pulignani, Silvia; Baffigi, Federica; Fulgentini, Lorenzo; Koester, Petra; Cresci, Monica; Vecoli, Cecilia; Lamia, Debora; Russo, Giorgio; Panetta, Daniele; Tripodi, Maria; Gizzi, Leonida A; Labate, Luca

2016-09-01

Laser-driven electron accelerators are capable of producing high-energy electron bunches in shorter distances than conventional radiofrequency accelerators. To date, our knowledge of the radiobiological effects in cells exposed to electrons using a laser-plasma accelerator is still very limited. In this study, we compared the dose-response curves for micronucleus (MN) frequency and telomere length in peripheral blood lymphocytes exposed to laser-driven electron pulse and X-ray radiations. Additionally, we evaluated the effects on cell survival of in vitro tumor cells after exposure to laser-driven electron pulse compared to electron beams produced by a conventional radiofrequency accelerator used for intraoperative radiation therapy. Blood samples from two different donors were exposed to six radiation doses ranging from 0 to 2 Gy. Relative biological effectiveness (RBE) for micronucleus induction was calculated from the alpha coefficients for electrons compared to X rays (RBE = alpha laser/alpha X rays). Cell viability was monitored in the OVCAR-3 ovarian cancer cell line using trypan blue exclusion assay at day 3, 5 and 7 postirradiation (2, 4, 6, 8 and 10 Gy). The RBE values obtained by comparing the alpha values were 1.3 and 1.2 for the two donors. Mean telomere length was also found to be reduced in a significant dose-dependent manner after irradiation with both electrons and X rays in both donors studied. Our findings showed a radiobiological response as mirrored by the induction of micronuclei and shortening of telomere as well as by the reduction of cell survival in blood samples and cancer cells exposed in vitro to laser-generated electron bunches. Additional studies are needed to improve preclinical validation of the radiobiological characteristics and efficacy of laser-driven electron accelerators in the future.

Inhibitory effect of gallic acid on CCl4-mediated liver fibrosis in mice.

PubMed

Wang, Jing; Tang, Long; White, James; Fang, Jing

2014-05-01

The aim of this study was to investigate the effect of gallic acid (GA) on liver fibrosis induced by carbon tetrachloride (CCl4). Male BALB/c mice were randomly divided into four groups: normal control group (group A), CCl4-induced liver injury control group (group B), and CCl4 induction with GA of low dose (5 mg/kg) and high dose (15 mg/kg) treatment group (group C and group D). GA was intra-gastric given for mice once a day after 2 weeks of CCl4 induction. Animals were killed at the eighth week. Degrees of fibrosis and collagen percentage were measured. Hyaluronic acid (HA), type IV collagen (cIV), malondialdehyde (MDA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (γ-GT) were determined. Expression of matrix metalloproteinases-2 (MMP-2) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) mRNA levels were examined by RT-PCR. Western blotting was carried out to evaluate the changes of MMP-2 protein. HE and VG stainings showed GA in a dose-dependent manner improved significantly the fibrosis condition in CCl4-injured mice (P < 0.05 or P < 0.01). Also, the concentrations of HA, cIV, and MDA, as well as the serum levels of ALT, AST, and γ-GT were markedly reduced by GA (P < 0.05 or P < 0.01), and decreases in MMP-2, TIMP-1 mRNA, and MMP-2 protein were observed as well (P < 0.05 or P < 0.01). GA could exert protective effect on liver injury and reduce liver fibrosis induced by CCl4 in mice, which might be through the inhibition of hepatic stellate cell activity.

Fluoride Induces Endoplasmic Reticulum Stress and Inhibits Protein Synthesis and Secretion

PubMed Central

Sharma, Ramaswamy; Tsuchiya, Masahiro; Bartlett, John D.

2008-01-01

Background Exposure to excessive amounts of fluoride (F−) causes dental fluorosis in susceptible individuals; however, the mechanism of F−-induced toxicity is unclear. Previously, we have shown that high-dose F− activates the unfolded protein response (UPR) in ameloblasts that are responsible for dental enamel formation. The UPR is a signaling pathway responsible for either alleviating endoplasmic reticulum (ER) stress or for inducing apoptosis of the stressed cells. Objectives In this study we determined if low-dose F− causes ER stress and activates the UPR, and we also determined whether F− interferes with the secretion of proteins from the ER. Methods We stably transfected the ameloblast-derived LS8 cell line with secreted alkaline phosphatase (SEAP) and determined activity and localization of SEAP and F−-mediated induction of UPR proteins. Also, incisors from mice given drinking water containing various concentrations of F− were examined for eucaryotic initiation factor-2, subunit alpha (eIF2α) phosphorylation. Results We found that F− decreases the extracellular secretion of SEAP in a linear, dose-dependent manner. We also found a corresponding increase in the intracellular accumulation of SEAP after exposure to F−. These changes are associated with the induction of UPR proteins such as the molecular chaperone BiP and phosphorylation of the UPR sensor PKR-like ER kinase, and its substrate, eIF2α. Importantly, F−-induced phosphorylation of eIF2αwas confirmed in vivo. Conclusions These data suggest that F− initiates an ER stress response in ameloblasts that interferes with protein synthesis and secretion. Consequently, ameloblast function during enamel development may be impaired, and this may culminate in dental fluorosis. PMID:18795154

Irreversible EGFR Inhibitor EKB-569 Targets Low-LET γ-Radiation-Triggered Rel Orchestration and Potentiates Cell Death in Squamous Cell Carcinoma

PubMed Central

Aravindan, Natarajan; Thomas, Charles R.; Aravindan, Sheeja; Mohan, Aswathi S.; Veeraraghavan, Jamunarani; Natarajan, Mohan

2011-01-01

EKB-569 (Pelitinib), an irreversible EGFR tyrosine kinase inhibitor has shown potential therapeutic efficiency in solid tumors. However, cell-killing potential in combination with radiotherapy and its underlying molecular orchestration remain to be explored. The objective of this study was to determine the effect of EKB-569 on ionizing radiation (IR)-associated NFκB-dependent cell death. SCC-4 and SCC-9 cells exposed to IR (2Gy) with and without EKB-569 treatment were analyzed for transactivation of 88 NFκB pathway molecules, NFκB DNA-binding activity, translation of the NFκB downstream mediators, Birc1, 2 and 5, cell viability, metabolic activity and apoptosis. Selective targeting of IR-induced NFκB by EKB-569 and its influence on cell-fate were assessed by overexpressing (p50/p65) and silencing (ΔIκBα) NFκB. QPCR profiling after IR exposure revealed a significant induction of 74 NFκB signal transduction molecules. Of those, 72 were suppressed with EKB-569. EMSA revealed a dose dependent inhibition of NFκB by EKB-569. More importantly, EKB-569 inhibited IR-induced NFκB in a dose-dependent manner, and this inhibition was sustained up to at least 72 h. Immunoblotting revealed a significant suppression of IR-induced Birc1, 2 and 5 by EKB-569. We observed a dose-dependent inhibition of cell viability, metabolic activity and apoptosis with EKB-569. EKB-569 significantly enhanced IR-induced cell death and apoptosis. Blocking NFκB improved IR-induced cell death. Conversely, NFκB overexpression negates EKB-569 -induced cell-killing. Together, these pre-clinical data suggest that EKB-569 is a radiosensitizer of squamous cell carcinoma and may mechanistically involve selective targeting of IR-induced NFκB-dependent survival signaling. Further pre-clinical in-vivo studies are warranted. PMID:22242139

Differential repair of radiation-induced DNA damage in cells of human squamous cell carcinoma and the effect of caffeine and cysteamine on induction and repair of DNA double-strand breaks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smeets, M.F.M.A.; Mooren, E.H.M.; Abdel-Wahab, A.H.A.

1994-11-01

The goal of these experiments was to investigate further the relationship between DNA double-strand breaks and cell killing in human tumor cells, first by comparing different cell lines, and second by radiomodification studies. Field-inversion gel electrophoresis was used to quantify double-strand breaks. Two subclones of the radioresistant human squamous cell carcinoma line SQ20B (SQD9 and SQG6) were compared. These subclones differed in DNA index by a factor of 1.7 but showed the same resistance to radiation as cells of the parental cell line. It was found that, although induction of DSBs was not significantly different in the two cell lines,more » the t{sub 1/2} of the fast component of repair was significantly shorter for SQD9 cells, leading to greater overall repair which was not reflected in increased survival. Caffeine and cysteamine were tested as modifiers of radiosensitivity, using the radioresistant SQ20B line and the radiosensitive SCC61 cell line. No effect of caffeine was seen when the drug was present only during irradiation. Postirradiation incubations with caffeine, however, resulted in a dose reduction factor greater than 2.0 in cell survival for both cell lines. In contrast, induction of DSBs was reduced by caffeine, and no effect on DSB repair was observed. Cysteamine led to a dose protection factor greater than 1.8 in cell survival in both cell lines. A reduction in induced DSBs was found at high doses corresponding approximately with the increase in cell survival. Over the same (low) dose range, however, the correlation between DSB induction and cell killing was poor. These data indicate that DSB induction does not correlate well with cell killing either for different cell lines, for radiochemical modification (cysteamine) or for some other types of modification (caffeine). 31 refs., 8 figs.« less

Hematopoietic stem cell injury induced by ionizing radiation.

PubMed

Shao, Lijian; Luo, Yi; Zhou, Daohong

2014-03-20

Exposure to ionizing radiation (IR) as the result of nuclear accidents or terrorist attacks is a significant threat and a major medical concern. Hematopoietic stem cell (HSC) injury is the primary cause of death after accidental or intentional exposure to a moderate or high dose of IR. Protecting HSCs from IR should be a primary goal in the development of novel medical countermeasures against radiation. Significant progress has been made in our understanding of the mechanisms by which IR causes HSC damage. The mechanisms include (i) induction of HSC apoptosis via the p53-Puma pathway; (ii) promotion of HSC differentiation via the activation of the G-CSF/Stat3/BATF-dependent differentiation checkpoint; (iii) induction of HSC senescence via the ROS-p38 pathway; and (iv) damage to the HSC niche. Induction of apoptosis in HSCs and hematopoietic progenitor cells is primarily responsible for IR-induced acute bone marrow (BM) injury. Long-term BM suppression caused by IR is mainly attributable to the induction of HSC senescence. However, the promotion of HSC differentiation and damage to the HSC niche can contribute to both the acute and long-term effects of IR on the hematopoietic system. In this review, we have summarized a number of recent findings that provide new insights into the mechanisms whereby IR damages HSCs. These findings will provide new opportunities for developing a mechanism-based strategy to prevent and/or mitigate IR-induced BM suppression. Antioxid.

Anesthetic activity of plant essential oils on Cyprinus carpio (koi carp).

PubMed

Khumpirapang, Nattakanwadee; Pikulkaew, Surachai; Anuchapreeda, Songyot; Okonogi, Siriporn

2018-03-19

The aims of this study were to investigate the anesthetic and cytotoxic effects of essential oils (EOs) of Ocimum basilicum (OBO), O. canum (OCO), and O. sanctum (OSO) on Cyprinus carpio (koi carp). For anesthetic effect, induction time to surgical anesthesia and recovery time were determined. For cytotoxicity effect, viability of fish peripheral blood nuclear cells (PBMCs) was investigated. Results indicated that increasing oil concentration caused significant (p < 0.01) decrease of induction time. OSO at 100, 200, and 300 mg/L gave the induction time of 169.5 ± 10.2, 62.8 ± 2.3, 45.3 ± 2.2 sec, respectively, significantly shorter than OCO, and OBO. The recovery time of anesthetized fish was dose dependent (p <0.01). Among them, OCO showed the longest recovery time of 313.0 ± 8.1, 420.7 ± 12.6, 616.6 ± 12.1 sec for concentrations of 100, 200, and 300 mg/L, respectively, followed by OSO and OBO, respectively. Within 10 min contact time of the EOs and fish PBMCs, the fish PBMC viability was higher than 80%. Increase contact time and EO concentration caused an increase in cytotoxicity to fish PBMC. OBO showed less toxic than OSO and OCO. Based on the desired induction and recovery times for anesthetizing koi carp, OBO, OCO, and OSO at 300, 200, and 100 mg/L, respectively were suggested to be the most suitable. It was concluded that OBO, OCO, and OSO can be used as natural anesthetics for fish.

Induction of the pi class of glutathione S-transferase by carnosic acid in rat Clone 9 cells via the p38/Nrf2 pathway.

PubMed

Lin, Chia-Yuan; Wu, Chi-Rei; Chang, Shu-Wei; Wang, Yu-Jung; Wu, Jia-Jiuan; Tsai, Chia-Wen

2015-06-01

Induction of phase II enzymes is important in cancer chemoprevention. We compared the effect of rosemary diterpenes on the expression of the pi class of glutathione S-transferase (GSTP) in rat liver Clone 9 cells and the signaling pathways involved. Culturing cells with 1, 5, 10, or 20 μM carnosic acid (CA) or carnosol (CS) for 24 h in a dose-dependent manner increased the GSTP expression. CA was more potent than CS. The RNA level and the enzyme activity of GSTP were also enhanced by CA treatment. Treatment with 10 μM CA highly induced the reporter activity of the enhancer element GPEI. Furthermore, CA markedly increased the translocation of nuclear factor erythroid-2 related factor 2 (Nrf2) from the cytosol to the nucleus after 30 to 60 min. CA the stimulated the protein induction of p38, nuclear Nrf2, and GSTP was diminished in the presence of SB203580 (a p38 inhibitor). In addition, SB203580 pretreatment or silencing of Nrf2 by siRNA suppressed the CA-induced GPEI-DNA binding activity and GSTP protein expression. Knockdown of p38 or Nrf2 by siRNA abolished the activation of p38 and Nrf2 as well as the protein induction and enzyme activity of GSTP by CA. These results suggest that CA up-regulates the expression and enzyme activity of GSTP via the p38/Nrf2/GPEI pathway.

Biochemical Characterization of Porphobilinogen Deaminase–Deficient Mice During Phenobarbital Induction of Heme Synthesis and the Effect of Enzyme Replacement

PubMed Central

Johansson, Annika; Möller, Christer; Fogh, Jens; Harper, Pauline

2003-01-01

Acute intermittent porphyria (AIP) is a genetic disorder caused by a deficiency of porphobilinogen deaminase (PBGD), the 3rd enzyme in heme synthesis. It is clinically characterized by acute attacks of neuropsychiatric symptoms and biochemically by increased urinary excretion of the porphyrin precursors porphobilinogen (PBG) and 5-aminolevulinic acid (ALA). A mouse model that is partially deficient in PBGD and biochemically mimics AIP after induction of the hepatic ALA synthase by phenobarbital was used in this study to identify the site of formation of the presumably toxic porphyrin precursors and study the effect of enzyme-replacement therapy by using recombinant human PBGD (rhPBGD). After 4 d of phenobarbital administration, high levels of PBG and ALA were found in liver, kidney, plasma, and urine of the PBGD-deficient mice. The administration of rhPBGD intravenously or subcutaneously after a 4-d phenobarbital induction was shown to lower the PBG level in plasma in a dose-dependent manner with maximal effect seen after 30 min and 2 h, respectively. Injection of rhPBGD subcutaneously twice daily during a 4-d phenobarbital induction reduced urinary PBG excretion to 25% of the levels found in PBGD-deficient mice administered with only phenobarbital. This study points to the liver as the main producer of PBG and ALA in the phenobarbital-induced PBGD-deficient mice and demonstrates efficient removal of accumulated PBG in plasma and urine by enzyme-replacement therapy. PMID:15208740

Upregulation of MMP12 and its activity by UVA1 in human skin: potential implications for photoaging.

PubMed

Tewari, Angela; Grys, Katarzyna; Kollet, Jutta; Sarkany, Robert; Young, Antony R

2014-10-01

UVA1 constitutes around 75% of the terrestrial UV radiation, and most of the output of artificial tanning sources. However, the molecular effects of UVA1 in human skin in vivo are surprisingly poorly understood. We have examined time-dependent whole-genome expression, along with mRNA and protein changes in the skin after one minimal erythema dose of spectrally pure UVA1 (50 J cm(-2)) and 300 nm UVB (30 mJ cm(-2)). After 24 hours, the genes induced to the greatest extent were those involved in extracellular matrix remodeling with both UVA1 (P=5.5e-7) and UVB (P=2.9e-22). UVA1 and UVB caused different effects on matrix metalloproteinase (MMP) expression: UVB induced MMP1, MMP3, and MMP10 mRNA at 24 hours to a much greater extent than UVA1. MMP12 induction by UVA1 at 6 hours is marked and much greater than that by UVB. We have found that MMP12 mRNA induction by UVA1 resulted in expression of MMP12 protein, which is functional as an elastase. This induction of elastase activity did not occur with UVB. We hypothesize that the UVA1 induction of MMP12 mediates some of its photoaging effects, particularly by contributing to elastin degeneration in late solar elastosis. MMP12 is a good marker of UVA1 exposure.

CDDO-Im protects from acetaminophen hepatotoxicity through induction of Nrf2-dependent genes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reisman, Scott A.; Buckley, David B.; Tanaka, Yuji

CDDO-Im is a synthetic triterpenoid recently shown to induce cytoprotective genes through the Nrf2-Keap1 pathway, an important mechanism for the induction of cytoprotective genes in response to oxidative stress. Upon oxidative or electrophilic insult, the transcription factor Nrf2 translocates to the nucleus, heterodimerizes with small Maf proteins, and binds to antioxidant response elements (AREs) in the upstream promoter regions of various cytoprotective genes. To further elucidate the hepatoprotective effects of CDDO-Im, wild-type and Nrf2-null mice were pretreated with CDDO-Im (1 mg/kg, i.p.) or vehicle (DMSO), and then administered acetaminophen (500 mg/kg, i.p.). Pretreatment of wild-type mice with CDDO-Im reduced livermore » injury caused by acetaminophen. In contrast, hepatoprotection by CDDO-Im was not observed in Nrf2-null mice. CDDO-Im increased Nrf2 protein expression and Nrf2-ARE binding in wild-type, but not Nrf2-null mice. Furthermore, CDDO-Im increased the mRNA expression of the Nrf2 target genes NAD(P)H: quinone oxidoreductase-1 (Nqo1); glutamate-cysteine ligase, catalytic subunit (Gclc); and heme-oxygenase-1 (Ho-1), in both a dose- and time-dependent manner. Conversely, CDDO-Im did not induce Nqo1, Gclc, and Ho-1 mRNA expression in Nrf2-null mice. Collectively, the present study shows that CDDO-Im pretreatment induces Nrf2-dependent cytoprotective genes and protects the liver from acetaminophen-induced hepatic injury.« less

Primula auriculata Extracts Exert Cytotoxic and Apoptotic Effects against HT-29 Human Colon Adenocarcinoma Cells

PubMed Central

Behzad, Sahar; Ebrahim, Karim; Mosaddegh, Mahmoud; Haeri, Ali

2016-01-01

Primula auriculata (Tootia) is one of the most important local medicinal plants in Hamedan district, Iran. To investigate cytotoxicity and apoptosis induction of crude methanolic extract and different fraction of it, we compared several methods on HT-29 human colon Adenocarcinoma cells. Cancer cell proliferation was measured by 3-(4, 5‑dimethylthiazolyl)2, 5‑diphenyl‑tetrazolium bromide (MTT) assay and apoptosis induction was analyzed by fluorescence microscopy (acridin orange/ethidium bromide, annexin V/propidium iodide staining, TUNEL assay and Caspase-3 activity assay). Crude methanolic extract (CM) inhibited the growth of malignant cells in a dose-dependent manner. Among solvent fractions, the dichloromethane fraction (CF) was found to be the most toxic compared to other fractions. With double staining methods, high percentage of 40 µg/mL of (CM) and (CF) treated cells exhibited typical characteristics of apoptotic cells. Apoptosis induction was also revealed by apoptotic fragmentation of nuclear DNA and activation of caspas-3 in treated cells. These findings indicate that crude methanolic extract and dichloromethan fraction of P.auriculata induced apoptosis and inhibited proliferation in colon cancer cells and could be used as a source for new lead structures in drug design to combat colon cancer. PMID:27610172

Radiation induction of cancer of the skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fry, R.J.M.; Storer, J.B.; Burns, F.J.

1985-01-01

The induction of epidermal tumors was studied using exposures to 25 kV x-rays with or without subsequent exposures to 12-0-tetradeconyl phorbol-13 acetate (TPA) or ultraviolet radiation (uvr) 280-400 nm. Fractionation regimens and total exposure up to 4000R produced no squamous cell carcinomas. When these regimes were followed by TPA an incidence of about 80% was obtained, and incidence of 60% when uvr exposures followed the x-irradiation. A dose-dependent increase in fibrosarcomas was found when x-irradiation was followed by 24 weeks of topical treatment with TPA. These results support the contention that uvr can enhance the expression of cells initiated bymore » x-rays. The experimental evidence is compared with the data from the tinea capitis patients treated with x-rays. In C3HF/He male mice exposed to 50, 100, 150 and 200 rads /sup 137/Cs gamma rays the induction rate for fibrosarcomas was 2.9 x 10/sup -4/ per cGy/per mouse. This result compares with 2.5 x 10/sup -6/ transformations per surviving cell per cGy with 10T1/2 cells that are fibroblasts derived from C3H mice. 16 refs., 1 fig., 1 tab.« less

O-Glycosylation in Cell Wall Proteins in Scedosporium prolificans Is Critical for Phagocytosis and Inflammatory Cytokines Production by Macrophages

PubMed Central

Xisto, Mariana I. D. S.; Bittencourt, Vera C. B.; Liporagi-Lopes, Livia Cristina; Haido, Rosa M. T.; Mendonça, Morena S. A.; Sassaki, Guilherme; Figueiredo, Rodrigo T.; Romanos, Maria Teresa V.; Barreto-Bergter, Eliana

2015-01-01

In this study, we analyze the importance of O-linked oligosaccharides present in peptidorhamnomannan (PRM) from the cell wall of the fungus Scedosporium prolificans for recognition and phagocytosis of conidia by macrophages. Adding PRM led to a dose-dependent inhibition of conidia phagocytosis, whereas de-O-glycosylated PRM did not show any effect. PRM induced the release of macrophage-derived antimicrobial compounds. However, O-linked oligosaccharides do not appear to be required for such induction. The effect of PRM on conidia-induced macrophage killing was examined using latex beads coated with PRM or de-O-glycosylated PRM. A decrease in macrophage viability similar to that caused by conidia was detected. However, macrophage killing was unaffected when beads coated with de-O-glycosylated PRM were used, indicating the toxic effect of O-linked oligosaccharides on macrophages. In addition, PRM triggered TNF-α release by macrophages. Chemical removal of O-linked oligosaccharides from PRM abolished cytokine induction, suggesting that the O-linked oligosaccharidic chains are important moieties involved in inflammatory responses through the induction of TNF-α secretion. In summary, we show that O-glycosylation plays a role in the recognition and uptake of S. prolificans by macrophages, killing of macrophages and production of pro- inflammatory cytokines. PMID:25875427

Diosmin reduces cell viability of A431 skin cancer cells through apoptotic induction.

PubMed

Buddhan, Rajamanickam; Manoharan, Shanmugam

2017-01-01

Aim of the present study was to evaluate the in vitro cytotoxic potential of the diosmin in A431 skin cancer cells. The cytotoxic (anti-cell proliferative) potential of diosmin in A431 cells was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay (cell viability), dual staining (apoptotic induction), dichloro-dihydro-fluorescein diacetate assay (reactive oxygen species [ROS] generation), DNA fragmentation study, Western blotting analysis (apoptotic markers expression) and flow cytometry (cell cycle arrest). Diosmin reduced the cell viability of A431 cells in a dose-dependent fashion and the inhibitory concentration 50% value was attained at 45 μg/ml using MTT assay. Diosmin at a concentration of 45 μg/ml generated excessive ROS in A431 cells, as compared to untreated cells. Diosmin treated A431 cells also revealed multiple DNA fragments than the untreated cells. Diosmin upregulated the expression of p53, caspases 3 and 9 and downregulated the expression of Bcl-2, matrix metalloproteinases-2 and 9 in A431 cells. The cytotoxic or anti-cell proliferative potential of diosmin is due to its ROS-mediated apoptotic induction potential, as well as due to its role in the inhibition of invasion in the A431 cells.

Induction of tyrosine hydroxylase mRNA by nicotine in rat midbrain is inhibited by mifepristone

PubMed Central

Radcliffe, Pheona M.; Sterling, Carol R.; Tank, A. William

2009-01-01

Repeated nicotine administration induces tyrosine hydroxylase (TH) mRNA in rat midbrain. In this study we investigate the mechanisms responsible for this response using two models of midbrain dopamine neurons, rat ventral midbrain slice explant cultures and mouse MN9D cells. In both models nicotine stimulates TH gene transcription rate in a dose-dependent manner. However, this stimulation is short-lived, lasting for 1 hr, but less than 3 hr, and is not sufficient to induce TH mRNA or TH protein. Nicotine elevates circulating glucocorticoids, which induce TH expression in some model systems. We tested the hypothesis that the effect of nicotine on midbrain TH mRNA is mediated by the glucocorticoid receptor. When rats are administered the glucocorticoid receptor antagonist mifepristone, the induction of TH mRNA by nicotine in both substantia nigra and ventral tegmentum is inhibited. Furthermore, the glucocorticoid receptor agonist dexamethasone stimulates TH gene transcription for sustained periods of time in both midbrain slices and MN9D cells, leading to induction of TH mRNA and TH protein. Our results are consistent with the hypothesis that nicotine induces TH mRNA in midbrain by elevating glucocorticoids, which then act on glucocorticoid receptors in dopamine neurons leading to transcriptional activation of the TH gene. PMID:19476543

Evaluation of Pharmacokinetic Interactions Between Lesinurad, a New Selective Urate Reabsorption Inhibitor, and CYP Enzyme Substrates Sildenafil, Amlodipine, Tolbutamide, and Repaglinide.

PubMed

Gillen, Michael; Yang, Chun; Wilson, David; Valdez, Shakti; Lee, Caroline; Kerr, Bradley; Shen, Zancong

2017-07-01

Lesinurad is a selective uric acid reabsorption inhibitor approved for the treatment of hyperuricemia associated with gout in combination with xanthine oxidase inhibitors. In vitro assays indicate that lesinurad is an inducer of CYPs in the order CYP3A > CYP2C8 > CYP2C9 > CYP2C19 > CYP2B6 and an inhibitor of CYP2C8 and CYP2C9. To investigate the drug interaction potential of lesinurad, clinical drug interaction studies were conducted. Open-label studies in volunteers investigated the effects of single-/multiple-dose lesinurad on the pharmacokinetics of sildenafil and amlodipine (CYP3A4 induction), tolbutamide (CYP2C9 inhibition/induction), and repaglinide (CYP2C8 inhibition/induction). There was no apparent induction of CYP2C8 and CYP2C9 following repeated lesinurad administration, although no inhibition of CYP2C9 and modest inhibition of CYP2C8 were observed following single-dose lesinurad. Consistent with in vitro observations, lesinurad (200 mg once daily) was an inducer of CYP3A based on the effects on sildenafil exposure. Sildenafil exposure decreased by approximately 34% for C max and AUC when administered with multiple-dose lesinurad 200 mg and allopurinol 300 mg, relative to sildenafil alone. During lesinurad therapy, the possibility of reduced efficacy of concomitant drugs that are CYP3A substrates should be considered and their efficacy monitored because of induction of CYP3A by lesinurad. © 2017, The American College of Clinical Pharmacology.

Basiliximab induction in kidney transplantation with donation after cardiac death donors

PubMed Central

YAO, XUPING; WENG, GUOBIN; WEI, JUNJUN; GAO, WENBO

2016-01-01

Basiliximab is a monoclonal antibody that binds to the α-chain of the interleukin (IL)-2 receptor. It is used as induction therapy in kidney transplantation. The objective of the present study was to evaluate induction therapy with single-dose basiliximab (Simulect®) in kidney transplantation with donation after cardiac death (DCD) donors. A total of 33 DCD kidney transplants were performed between December 2010 and July 2013 in patients who received single-dose basiliximab (20 mg) as induction therapy. The maintenance immunosuppression included calcineurin inhibitor (cyclosporine A or tacrolimus), mycophenolate mofetil and corticosteroids. The follow-up time was 1 year. The mean ages of the DCD donors and recipients were 29.3 and 41.1 years, respectively. Within the 1-year follow-up, the overall incidence of acute rejection was 9.1%. There were 10 cases of delayed graft function among the recipients. Mean serum creatinine values at 1 week and at 1, 3, 6, 9 and 12 months post-transplantation were 257.6, 238.2, 194.5, 159.3, 137.9 and 110.8 µmol/l, respectively, with a favorable trend to allograft function recovery over time. The 1-year patient and graft survival rates were 96.9 and 90.9%, respectively, with an infection rate of 24.2%. Increased alanine aminotransferase/aspartate transaminase levels in only 2 patients were considered to be associated with basiliximab. This experience with single-dose basiliximab for induction therapy in DCD kidney transplantation showed that favorable clinical outcomes were achieved in terms of graft survival and function within 1 year. PMID:27284346

Scattered dose to gonads and associated risks from radiotherapy for common pediatric malignancies : a phantom study.

PubMed

Mazonakis, Michalis; Zacharopoulou, Fotini; Kachris, Stefanos; Varveris, Charalambos; Damilakis, John; Gourtsoyiannis, Nicholas

2007-06-01

To measure the scattered dose to ovaries and testes from radiotherapy for common pediatric malignancies and to assess the relevant risks for radiation-induced gonadal damage and hereditary disorders in future generations. Radiotherapy for central nervous system tumors, acute leukemia, neuroblastoma, Hodgkin's disease, Wilms' tumor, and sarcoma was simulated on three humanoid phantoms representing patients of 5, 10, and 15 years of age. Ovarian and testicular dose measurements were performed using thermoluminescent dosimeters on a linear accelerator with multileaf collimator (MLC) producing 6-MV X-rays. The effect of lead block introduction into the primary beam on the gonadal dose was evaluated. Gonadal dose from radiotherapy for abdominal tumors was measured using an 18-MV photon beam. For a tumor dose range of 12-55 Gy, the scattered dose to ovaries was 0.5-62.4 cGy depending upon the patient's age (corresponding phantom) and treatment site. The corresponding dose to testes was 0.4-145.0 cGy. The use of blocks for field shaping can increase the gonadal dose up to a factor of 2.0 compared to that measured using MLC. Abdominal irradiation with 18-MV instead of 6-MV X-rays reduced the gonadal dose by more than 1.3 times. For female and male patients, the risk for induction of hereditary disorders was less than 81 x 10(-4) and 188 x 10(-4), respectively. The present dosimetric data suggest that pediatric radiotherapy is not associated with a risk for permanent damage to gonads excluded from the treatment volume. The risk for development of hereditary disorders in offspring conceived after exposure is low.

Comparison of consolidation strategies in acute myeloid leukemia: high-dose cytarabine alone versus intermediate-dose cytarabine combined with anthracyclines.

PubMed

Kim, Dae Sik; Kang, Ka-Won; Lee, Se Ryeon; Park, Yong; Sung, Hwa Jung; Kim, Seok Jin; Choi, Chul Won; Kim, Byung Soo

2015-09-01

We compared the efficacy of high-dose cytarabine alone to that of intermediate-dose cytarabine combined with anthracyclines as consolidation therapy. Patients enrolled in the Korea University acute myeloid leukemia (AML) registry received remission induction chemotherapy with the same standard induction regimen (idarubicin and cytarabine 3 + 7). Postremission therapy was performed for three or four cycles according to one of the following regimens: high-dose cytarabine (3 g/m(2)) or combination of intermediate-dose cytarabine (1 g/m(2)) with anthracyclines (idarubicin or mitoxantrone). Among the 443 AML patients enrolled in the registry, 145 patients received consolidation chemotherapy. The median overall survival (OS) and relapse-free survival (RFS) in the high-dose cytarabine group were significantly longer than those in the anthracycline combination group (OS, not reached vs. 16.6 months, p = 0.045; RFS, 38.6 months vs. 11.0 months, p = 0.011). The median duration of neutropenia was longer in the anthracycline combination group than in the high-dose cytarabine group (8 vs. 10 days, p = 0.001). This study suggests that high-dose cytarabine consolidation may produce superior outcomes than combination treatment with intermediate-dose cytarabine and anthracyclines and that the addition of anthracyclines during AML consolidation has limited value as compared to cytarabine intensification.

Effective dose of salmon GnRha for induction of ovulation in channel catfish, Ictalurus punctatus

USDA-ARS?s Scientific Manuscript database

The present study was conducted to determine the minimum effective salmon Gonadotropin Releasing Hormone analog (sGnRHa) dose to stimulate ovulation in channel catfish. Four doses of sGnRHa (0, 5, 10 and 25 µg /Kg) were compared with commonly used 100 µg mammalian Luteinizing Hormone Releasing Hor...

Non-Targeted Effects and the Dose Response for Heavy Ion Tumorigenesis

NASA Technical Reports Server (NTRS)

Chappell, Lori J.; Cucinotta, Francis A.

2010-01-01

There is no human epidemiology data available to estimate the heavy ion cancer risks experienced by astronauts in space. Studies of tumor induction in mice are a necessary step to estimate risks to astronauts. Previous experimental data can be better utilized to model dose response for heavy ion tumorigenesis and plan future low dose studies.

Induction of Micronuclei in Human Fibroblasts from the Los Alamos High Energy Neutron Beam

NASA Technical Reports Server (NTRS)

Cox, Bradley

2009-01-01

The space radiation field includes a broad spectrum of high energy neutrons. Interactions between these neutrons and a spacecraft, or other material, significantly contribute to the dose equivalent for astronauts. The 15 degree beam line in the Weapons Neutron Research beam at Los Alamos Nuclear Science Center generates a neutron spectrum relatively similar to that seen in space. Human foreskin fibroblast (AG1522) samples were irradiated behind 0 to 20 cm of water equivalent shielding. The cells were exposed to either a 0.05 or 0.2 Gy entrance dose. Following irradiation, micronuclei were counted to see how the water shield affects the beam and its damage to cell nuclei. Micronuclei induction was then compared with dose equivalent data provided from a tissue equivalent proportional counter.

Induction of mitochondrial-dependent apoptosis in T24 cells by a selenium (Se)-containing polysaccharide from Ginkgo biloba L. leaves.

PubMed

Chen, Dong; Sun, Shaopeng; Cai, Dawei; Kong, Guangqi

2017-08-01

In the present study, a selenium (Se)-containing polysaccharide (Se-GBLP) was isolated and purified from the leaves of Ginkgo biloba L. Se-GBLP was further evaluated for its antitumor activity against human bladder cancer T24 cells together with the possible mechanism of action. Our results showed that treatment of T24 cells with Se-GBLP (50, 100 and 200μg/ml) for 48h significantly inhibited cell viability and induced apoptosis in a dose- dependent manner. This Se-GBLP-induced apoptosis is associated with an increased protein expression of pro-apoptotic Bax, decreased expression of anti-apoptotic Bcl-2, loss of mitochondrial membrane potential, and cleavage of caspase-9, caspase-3 and PARP, suggesting that Se-GBLP-induced apoptosis occurs through the mitochondria-dependent pathway. Se-GBLP therefore merits further investigation as a promising preventive and/or therapeutic agent against human bladder cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Induction of p53-mediated apoptosis in splenocytes and thymocytes of C57BL/6 mice exposed to perfluorooctane sulfonate (PFOS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong, Guang-Hui, E-mail: ghdong@mail.cmu.edu.cn; Wang, Jing; Zhang, Ying-Hua

2012-10-15

Perfluorooctane sulfonate (PFOS) is a persistent environmental contaminant found in human and wildlife tissues. It has been reported that PFOS can cause atrophy of the immune organs and apoptosis of immunocytes in rodents. However, the mechanism behind such cause is still unclear. To understand the model of cell death and its mechanism on lymphoid cells in vivo, we conducted a dose/response experiment in which 4 groups of male adult C57BL/6 mice (12 mice per group) were dosed daily by oral gavage with PFOS at 0, 0.0167, 0.0833, or 0.8333 mg/kg/day, yielding targeted Total Administered Dose (TAD) of 0, 1, 5,more » or 50 mg PFOS/kg, respectively, over 60 days. The results showed that spleen and thymus weight were significantly reduced in the highest PFOS-dose-group (TAD 50 mg PFOS/kg) compared to the control group, whereas liver weight was significantly increased. We analyzed the cell death via apoptosis with an annexin-V/propidium iodide assay by flow cytometry, and observed that both the percentage of apoptosis and the expression of the pro-apoptotic proteins p53 in splenocytes and thymocytes increased in a dose-related manner after PFOS treatment. We also observed that PFOS induced p53-dependent apoptosis through the cooperation between the Bcl-xl down regulation without changing the Bcl-2 and Bax expression. The down regulation of Bcl-xl was strongly indicating mitochondrial involvement in apoptosis. It is confirmed by the release of cytochrome c and activation of caspase-3. All of these findings establish an important role of p53 and mitochondrial function in PFOS induced toxic environment in the host. -- Highlights: ► PFOS immunotoxicity is caused by induction of apoptosis via the p53 activation. ► PFOS exposure can induce down regulation of Bcl-xl. ► Mitochondria are involved in PFOS-induced apoptosis. ► PFOS exposure can cause the release of cytochrome c and activation of caspase-3.« less

Effects of very low fluences of high-energy protons or iron ions on irradiated and bystander cells.

PubMed

Yang, H; Magpayo, N; Rusek, A; Chiang, I-H; Sivertz, M; Held, K D

2011-12-01

In space, astronauts are exposed to radiation fields consisting of energetic protons and high atomic number, high-energy (HZE) particles at very low dose rates or fluences. Under these conditions, it is likely that, in addition to cells in an astronaut's body being traversed by ionizing radiation particles, unirradiated cells can also receive intercellular bystander signals from irradiated cells. Thus this study was designed to determine the dependence of DNA damage induction on dose at very low fluences of charged particles. Novel techniques to quantify particle fluence have been developed at the NASA Space Radiation Biology Laboratory (NSRL) at Brookhaven National Laboratory (BNL). The approach uses a large ionization chamber to visualize the radiation beam coupled with a scintillation counter to measure fluence. This development has allowed us to irradiate cells with 1 GeV/nucleon protons and iron ions at particle fluences as low as 200 particles/cm(2) and quantify biological responses. Our results show an increased fraction of cells with DNA damage in both the irradiated population and bystander cells sharing medium with irradiated cells after low fluences. The fraction of cells with damage, manifest as micronucleus formation and 53BP1 focus induction, is about 2-fold higher than background at doses as low as ∼0.47 mGy iron ions (∼0.02 iron ions/cell) or ∼70 μGy protons (∼2 protons/cell). In the irradiated population, irrespective of radiation type, the fraction of damaged cells is constant from the lowest damaging fluence to about 1 cGy, above which the fraction of damaged cells increases with dose. In the bystander population, the level of damage is the same as in the irradiated population up to 1 cGy, but it does not increase above that plateau level with increasing dose. The data suggest that at fluences of high-energy protons or iron ions less than about 5 cGy, the response in irradiated cell populations may be dominated by the bystander response.

Cellular determinants involving mitochondrial dysfunction, oxidative stress and apoptosis correlate with the synergic cytotoxicity of epigallocatechin-3-gallate and menadione in human leukemia Jurkat T cells.

PubMed

Tofolean, Ioana Teodora; Ganea, Constanta; Ionescu, Diana; Filippi, Alexandru; Garaiman, Alexandru; Goicea, Alexandru; Gaman, Mihnea-Alexandru; Dimancea, Alexandru; Baran, Irina

2016-01-01

We have investigated the growth-suppressive action of epigallocatechin-3-gallate (EGCG) on human leukemia Jurkat T cells. Results show a strong correlation between the dose-dependent reduction of clonogenic survival following acute EGCG treatments and the EGCG-induced decline of the mitochondrial level of Ca(2+). The cell killing ability of EGCG was synergistically enhanced by menadione. In addition, the cytotoxic effect of EGCG applied alone or in combination with menadione was accompanied by apoptosis induction. We also observed that in acute treatments EGCG displays strong antioxidant properties in the intracellular milieu, but concurrently triggers some oxidative stress generating mechanisms that can fully develop on a longer timescale. In parallel, EGCG dose-dependently induced mitochondrial depolarization during exposure, but this condition was subsequently reversed to a persistent hyperpolarized mitochondrial state that was dependent on the activity of respiratory Complex I. Fluorimetric measurements suggest that EGCG is a mitochondrial Complex III inhibitor and indicate that EGCG evokes a specific cellular fluorescence with emission at 400nm and two main excitation bands (at 330nm and 350nm) that may originate from a mitochondrial supercomplex containing dimeric Complex III and dimeric ATP-synthase, and therefore could provide a valuable means to characterize the functional properties of the respiratory chain. Copyright © 2015 Elsevier Ltd. All rights reserved.

Involvement of Endoplasmic Reticulum Stress, Autophagy, and Apoptosis in Advanced Glycation End Products-Induced Glomerular Mesangial Cell Injury

PubMed Central

Chiang, Chih-Kang; Wang, Ching-Chia; Lu, Tien-Fong; Huang, Kuo-How; Sheu, Meei-Ling; Liu, Shing-Hwa; Hung, Kuan-Yu

2016-01-01

Advanced glycation end-products (AGEs)-induced mesangial cell death is one of major causes of glomerulus dysfunction in diabetic nephropathy. Both endoplasmic reticulum (ER) stress and autophagy are adaptive responses in cells under environmental stress and participate in the renal diseases. The role of ER stress and autophagy in AGEs-induced mesangial cell death is still unclear. Here, we investigated the effect and mechanism of AGEs on glomerular mesangial cells. AGEs dose-dependently decreased mesangial cell viability and induced cell apoptosis. AGEs also induced ER stress signals in a time- and dose-dependent manner. Inhibition of ER stress with 4-phenylbutyric acid effectively inhibited the activation of eIF2α and CHOP signals and reversed AGEs-induced cell apoptosis. AGEs also activated LC-3 cleavage, increased Atg5 expression, and decreased p62 expression, which indicated the autophagy induction in mesangial cells. Inhibition of autophagy by Atg5 siRNAs transfection aggravated AGEs-induced mesangial cell apoptosis. Moreover, ER stress inhibition by 4-phenylbutyric acid significantly reversed AGEs-induced autophagy, but autophagy inhibition did not influence the AGEs-induced ER stress-related signals activation. These results suggest that AGEs induce mesangial cell apoptosis via an ER stress-triggered signaling pathway. Atg5-dependent autophagy plays a protective role. These findings may offer a new strategy against AGEs toxicity in the kidney. PMID:27665710

Enhanced thyroid hormone breakdown in hepatocytes by mutual induction of the constitutive androstane receptor (CAR, NR1I3) and arylhydrocarbon receptor by benzo[a]pyrene and phenobarbital.

PubMed

Schraplau, Anne; Schewe, Bettina; Neuschäfer-Rube, Frank; Ringel, Sebastian; Neuber, Corinna; Kleuser, Burkhard; Püschel, Gerhard P

2015-02-03

Xenobiotics may interfere with the hypothalamic-pituitary-thyroid endocrine axis by inducing enzymes that inactivate thyroid hormones and thereby reduce the metabolic rate. This induction results from an activation of xeno-sensing nuclear receptors. The current study shows that benzo[a]pyrene, a frequent contaminant of processed food and activator of the arylhydrocarbon receptor (AhR) activated the promoter and induced the transcription of the nuclear receptor constitutive androstane receptor (CAR, NR1I3) in rat hepatocytes. Likewise, phenobarbital induced the AhR transcription. This mutual induction of the nuclear receptors enhanced the phenobarbital-dependent induction of the prototypic CAR target gene Cyp2b1 as well as the AhR-dependent induction of UDP-glucuronosyltransferases. In both cases, the induction by the combination of both xenobiotics was more than the sum of the induction by either substance alone. By inducing the AhR, phenobarbital enhanced the benzo[a]pyrene-dependent reduction of thyroid hormone half-life and the benzo[a]pyrene-dependent increase in the rate of thyroid hormone glucuronide formation in hepatocyte cultures. CAR ligands might thus augment the endocrine disrupting potential of AhR activators by an induction of the AhR. Copyright © 2014. Published by Elsevier Ireland Ltd.

Urotensin II modulates hepatic fibrosis and portal hemodynamic alterations in rats.

PubMed

Kemp, William; Kompa, Andrew; Phrommintikul, Arintaya; Herath, Chandana; Zhiyuan, Jia; Angus, Peter; McLean, Catriona; Roberts, Stuart; Krum, Henry

2009-10-01

The influence of circulating urotensin II (UII) on liver disease and portal hypertension is unknown. We aimed to evaluate whether UII executes a pathogenetic role in the development of hepatic fibrosis and portal hypertension. UII was administered by continuous infusion over 4 wk in 20 healthy rats divided into three treatment groups, controls (saline, n = 7), low dose (UII, 1 nmol x kg(-1) x h(-1), n = 8), and high dose (UII, 3 nmol x kg(-1) x h(-1), n = 5). Hemodynamic parameters and morphometric quantification of fibrosis were assessed, and profibrotic cytokines and fibrosis markers were assayed in hepatic tissue. UII induced a significant dose-dependent increase in portal venous pressure (5.8 +/- 0.4, 6.4 +/- 0.3, and 7.6 +/- 0.7, respectively, P = 0.03). High-dose UII infusion was associated with an increase in hepatic transcript for transforming growth factor-beta (P < 0.05) and platelet-derived growth factor-beta (P = 0.06). Liver tissue hydroxyproline was elevated in the high-dose group (P < 0.05). No systemic hemodynamic alterations were noted. We concluded that UII infusion elevates portal pressure and induces hepatic fibrosis in normal rats. This response may be mediated via induction of fibrogenic cytokines. These findings have pathophysiological implications in human liver disease where increased plasma UII levels have been observed.

Dose-dependent difference of nuclear receptors involved in murine liver hypertrophy by piperonyl butoxide.

PubMed

Sakamoto, Yohei; Yoshida, Midori; Tamura, Kei; Takahashi, Miwa; Kodama, Yukio; Inoue, Kaoru

2015-12-01

Nuclear receptors play important roles in chemically induced liver hypertrophy in rodents. To clarify the involvement of constitutive androstane receptor (CAR) and other nuclear receptors in mouse liver hypertrophy induced by different doses of piperonyl butoxide (PBO), wild-type and CAR-knockout mice were administered PBO (200, 1,000, or 5,000 ppm) in the basal diet for 1 week. Increased liver weight and diffuse hepatocellular hypertrophy were observed at 5,000 ppm for both genotypes, accompanied by increased Cyp3a11 mRNA and CYP3A protein expression, suggesting that CAR-independent pathway, possibly pregnane X receptor (PXR), plays a major role in the induction of hypertrophy. Moreover, wild-type mice at 5,000 ppm showed enhanced hepatocellular hypertrophy and strong positive staining for CYP2B in the centrilobular area, suggesting the localized contribution of CAR. At 1,000 ppm, only wild-type mice showed liver weight increase and centrilobular hepatocellular hypertrophy concurrent with elevated Cyp2b10 mRNA expression and strong CYP2B staining, indicating that CAR was essential at 1,000 ppm. We concluded that high-dose PBO induced hypertrophy via CAR and another pathway, while lower dose of PBO induced a pathway mediated predominantly by CAR. The dose-responsiveness on liver hypertrophy is important for understanding the involvement of nuclear receptors.

Toxicity of Urban PM10 and Relation with Tracers of Biomass Burning.

PubMed

Van Den Heuvel, Rosette; Staelens, Jeroen; Koppen, Gudrun; Schoeters, Greet

2018-02-12

The chemical composition of particles varies with space and time and depends on emission sources, atmospheric chemistry and weather conditions. Evidence suggesting that particles differ in toxicity depending on their chemical composition is growing. This in vitro study investigated the biological effects of PM 10 in relation to PM-associated chemicals. PM 10 was sampled in ambient air at an urban traffic site (Borgerhout) and a rural background location (Houtem) in Flanders (Belgium). To characterize the toxic potential of PM 10 , airway epithelial cells (Beas-2B cells) were exposed to particles in vitro. Different endpoints were studied including cell damage and death (cell viability) and the induction of interleukin-8 (IL-8). The mutagenic capacity was assessed using the Ames II Mutagenicity Test. The endotoxin levels in the collected samples were analyzed and the oxidative potential (OP) of PM 10 particles was evaluated by electron paramagnetic resonance (EPR) spectroscopy. Chemical characteristics of PM 10 included tracers for biomass burning (levoglucosan, mannosan and galactosan), elemental and organic carbon (EC/OC) and polycyclic aromatic hydrocarbons (PAHs). Most samples displayed dose-dependent cytotoxicity and IL-8 induction. Spatial and temporal differences in PM 10 toxicity were seen. PM 10 collected at the urban site was characterized by increased pro-inflammatory and mutagenic activity as well as higher OP and elevated endotoxin levels compared to the background area. Reduced cell viability (-0.46 < r s < -0.35, p < 0.01) and IL-8 induction (-0.62 < r s < -0.67, p < 0.01) were associated with all markers for biomass burning, levoglucosan, mannosan and galactosan. Furthermore, direct and indirect mutagenicity were associated with tracers for biomass burning, OC, EC and PAHs. Multiple regression analyses showed levoglucosan to explain 16% and 28% of the variance in direct and indirect mutagenicity, respectively. Markers for biomass burning were associated with altered cellular responses and increased mutagenic activity. These findings may indicate a role of biomass burning in the observed adverse health effect of particulate matter.

Cytochrome P4501A induction, benzo[a]pyrene metabolism, and nucleotide adduct formation in fish hepatoma cells: Effect of preexposure to 3,3',4,4',5-pentachlorobiphenyl

USGS Publications Warehouse

Smeets, J.M.W.; Voormolen, A.; Tillitt, D.E.; Everaarts, J.M.; Seinen, W.; Vanden Berg, M.D.

1999-01-01

In PLHC-1 hepatoma cells, benzo[a]pyrene (B[a]P) caused a maximum induction of cytochrome P4501A (CYP1A) activity, measured as ethoxyresorufin O-deethylation (EROD), after 4 to 8 h of exposure, depending on the B[a]P concentration. The decline of EROD activity at longer exposure times was probably caused by the rapid metabolism of B[a]P in this system (57% metabolism within 4 h incubation). In subsequent experiments, PLHC-1 cells were preinduced with PCB 126 for 24 h and then received a dose of 10, 100, or 1,000 nM 3H-B[a]P. A 1-nM concentration of PCB 126 caused an 80-fold induction of CYP1A activity, resulting in an increase in B[a]P metabolism of less than 10%, except at the highest concentration of B[a]P (1,000 nM), where a 50% increase was observed. In another experiment, an 80-fold induction of CYP1A activity caused a 20% increase in the metabolism of B[a]P (100 nM), and RNA adduct formation was increased approximately twofold. These results indicate that, at exposure concentrations up to 100 nM B[a]P, CYP1A activity is not rate limiting for B[a]P metabolism. Furthermore, CYP1A seems to also he specifically involved in B[a]P activation in PLHC-1 cells. However, CYP1A induction causes only a relatively small increase in activation, probably because of the action of other enzymes involved in B[a]P activation and deactivation.

Intrathecal injection of carbenoxolone, a gap junction decoupler, attenuates the induction of below-level neuropathic pain after spinal cord injury in rats.

PubMed

Roh, Dae-Hyun; Yoon, Seo-Yeon; Seo, Hyoung-Sig; Kang, Suk-Yun; Han, Ho-Jae; Beitz, Alvin J; Lee, Jang-Hern

2010-07-01

The most common type of chronic pain following spinal cord injury (SCI) is central neuropathic pain and SCI patients typically experience mechanical allodynia and thermal hyperalgesia. The present study was designed to examine the potential role of astrocyte gap junction connectivity in the induction and maintenance of "below-level" neuropathic pain in SCI rats. We examined the effect of intrathecal treatment with carbenoxolone (CARB), a gap junction decoupler, on SCI-induced bilateral thermal hyperalgesia and mechanical allodynia during the induction phase (postoperative days 0 to 5) and the maintenance phase (days 15 to 20) following T13 spinal cord hemisection. Immunohistochemistry was performed to determine potential SCI-induced changes in spinal astrocyte activation and phosphorylation of the NMDA receptor NR1 subunit (pNR1). CARB administered during the induction period dose-dependently attenuated the development of bilateral thermal hyperalgesia and mechanical allodynia. Intrathecal CARB also significantly reduced the bilateral SCI-induced increase in GFAP-immunoreactive (ir) staining and the number of pNR1-ir cell profiles in the spinal cord dorsal horn compared to vehicle-treated rats. In contrast, CARB treatment during the maintenance phase had no effect on the established thermal hyperalgesia and mechanical allodynia nor on spinal GFAP expression or the number of pNR1-ir cell profiles. These results indicate that gap junctions play a critical role in the activation of astrocytes distant from the site of SCI and in the subsequent phosphorylation of NMDA receptors in the lumbar spinal cord. Both of these processes appear to contribute to the induction of bilateral below-level pain in SCI rats. Copyright 2010 Elsevier Inc. All rights reserved.

Post-electroconvulsive therapy recovery and reorientation time with methohexital and ketamine: a randomized, longitudinal cross-over design trial

PubMed Central

Yen, Tony; Khafaja, Mohamad; Lam, Nicholas; Crumbacher, James; Schrader, Ronald; Rask, John; Billstrand, Mary; Rothfork, Jacob; Abbott, Christopher C.

2014-01-01

Objectives Methohexital, a barbiturate anesthetic commonly used for electroconvulsive therapy (ECT), possesses dose-dependent anticonvulsant properties, and its use can interfere with effective seizure therapy in patients with high seizure thresholds. Ketamine, a NMDA-antagonist with epileptogenic properties not broadly used for ECT inductions, is a commonly used induction agent for general anesthesia. Recent studies suggest that the use of ketamine is effective in allowing successful ECT treatment in patients with high seizure thresholds without an increase in side-effects. In this preliminary study, we directly compared the recovery and re-orientation times of subjects receiving ketamine and methohexital for ECTs. Methods Twenty patients were randomized in a cross-over design to receive methohexital and ketamine for ECT inductions in alternating fashion for six trials. Primary outcome measures were recovery time (voluntary movement, respiratory effort, blood pressure, consciousness, and O2 saturation) and re-orientation time. Secondary outcome measures were individual recovery variables, side-effect occurrence, and seizure duration. Results: Overall recovery time was not significantly different between the two treatment arms (F(1,17) = 0.72, P = 0.41). Re-orientation time was faster in the methohexital arm (F(1,17) = 9.23, P = 0.007). Conclusion Ketamine inductions resulted in higher number of side-effects, higher subject dropout rates, and a longer reorientation time with respect to methohexital inductions. No significant difference in post-anesthesia recovery time was found between the ketamine and methohexital arms. Intolerability to ketamine affected a significant proportion of subjects, and suggests that ketamine should remain as an alternative or adjunctive agent for patients with high seizure thresholds. PMID:24755722

Spinal sigma-1 receptors activate NADPH oxidase 2 leading to the induction of pain hypersensitivity in mice and mechanical allodynia in neuropathic rats.

PubMed

Choi, Sheu-Ran; Roh, Dae-Hyun; Yoon, Seo-Yeon; Kang, Suk-Yun; Moon, Ji-Young; Kwon, Soon-Gu; Choi, Hoon-Seong; Han, Ho-Jae; Beitz, Alvin J; Oh, Seog-Bae; Lee, Jang-Hern

2013-08-01

We have recently demonstrated that spinal sigma-1 receptors (Sig-1Rs) mediate pain hypersensitivity in mice and neuropathic pain in rats. In this study, we examine the role of NADPH oxidase 2 (Nox2)-induced reactive oxygen species (ROS) on Sig-1R-induced pain hypersensitivity and the induction of chronic neuropathic pain. Neuropathic pain was produced by chronic constriction injury (CCI) of the right sciatic nerve in rats. Mechanical allodynia and thermal hyperalgesia were evaluated in mice and CCI-rats. Western blotting and dihydroethidium (DHE) staining were performed to assess the changes in Nox2 activation and ROS production in spinal cord, respectively. Direct activation of spinal Sig-1Rs with the Sig-1R agonist, PRE084 induced mechanical allodynia and thermal hyperalgesia, which were dose-dependently attenuated by pretreatment with the ROS scavenger, NAC or the Nox inhibitor, apocynin. PRE084 also induced an increase in Nox2 activation and ROS production, which were attenuated by pretreatment with the Sig-1R antagonist, BD1047 or apocynin. CCI-induced nerve injury produced an increase in Nox2 activation and ROS production in the spinal cord, all of which were attenuated by intrathecal administration with BD1047 during the induction phase of neuropathic pain. Furthermore, administration with BD1047 or apocynin reversed CCI-induced mechanical allodynia during the induction phase, but not the maintenance phase. These findings demonstrate that spinal Sig-1Rs modulate Nox2 activation and ROS production in the spinal cord, and ultimately contribute to the Sig-1R-induced pain hypersensitivity and the peripheral nerve injury-induced induction of chronic neuropathic pain. Copyright © 2013 Elsevier Ltd. All rights reserved.

Dose of Phenobarbital and Age of Treatment at Early Life are Two Key Factors for the Persistent Induction of Cytochrome P450 Enzymes in Adult Mouse Liver.

PubMed

Tien, Yun-Chen; Liu, Ke; Pope, Chad; Wang, Pengcheng; Ma, Xiaochao; Zhong, Xiao-bo

2015-12-01

Drug treatment of neonates and infants and its long-term consequences on drug responses have emerged in recent years as a major challenge for health care professionals. In the current study, we use phenobarbital as a model drug and mouse as an in vivo model to demonstrate that the dose of phenobarbital and age of treatment are two key factors for the persistent induction of gene expression and consequential increases of enzyme activities of Cyp2b, Cyp2c, and Cyp3a in adult livers. We show that phenobarbital treatment at early life of day 5 after birth with a low dose (<100 mg/kg) does not change expression and enzyme activities of Cyp2b, Cyp2c, and Cyp3a in adult mouse liver, whereas phenobarbital treatment with a high dose (>200 mg/kg) significantly increases expression and enzyme activities of these P450s in adult liver. We also demonstrate that phenobarbital treatment before day 10 after birth, but not at later ages, significantly increases mRNAs, proteins, and enzyme activities of the tested P450s. Such persistent induction of P450 gene expression and enzyme activities in adult livers by phenobarbital treatment only occurs within a sensitive age window early in life. The persistent induction in gene expression and enzyme activities is higher in female mice than in male mice for Cyp2b10 but not for Cyp2c29 and Cyp3a11. These results will stimulate studies to evaluate the long-term impacts of drug treatment with different doses at neonatal and infant ages on drug metabolism, therapeutic efficacy, and drug-induced toxicity throughout the rest of life. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Induction chemotherapy in metastatic neuroblastoma--does dose influence response? A critical review of published data standards, options and recommendations (SOR) project of the National Federation of French Cancer Centres (FNCLCC).

PubMed

Pinkerton, C R; Blanc Vincent, M P; Bergeron, C; Fervers, B; Philip, T

2000-09-01

The purpose of this study was to determine, from a review of published data, whether in stage 4 neuroblastoma in children over 1 year of age, the dose or scheduling of induction chemotherapy influenced the response rate in distant metastases. Publications relating to induction chemotherapy since the introduction of cisplatin/epipodophyllotoxin combinations were identified using Medline, Current Contents and personal reference lists. Thirteen publications were identified which described 17 regimens involving 948 children. The doses and the scheduling of the various regimens were compared with a standard regimen OPEC (vincristine, cisplatin, teniposide, cyclophosphamide). These were correlated with the reported response rates in the bone marrow. Due to a lack of standardisation in the nature of restaging investigations, timing of restaging and definitions of response it was difficult to compare all studies. The complete response rate at distant metastases ranged from less than 40% to over 90%. For individual drugs; the comparative doses given in each course ranged up to 4.2 g/m(2) for cyclophosphamide, 280 mg/m(2) for cisplatin, 600 mg/m(2) for etoposide and 4.5 mg/m(2) for vincristine. There was no evidence of any positive correlation between response rate in the marrow and either the dose of any individual drug or the schedule used. In contrast to a previous study which included a number of older studies where disease assessment was even more variable, this analysis has failed to show any justification for the routine use of very intensive induction regimens in this disease. Such an approach should only be taken in the context of randomised trials in which timing and methods of reassessment can be standardised. Until such studies demonstrate superiority either in terms of response rate or progression-free survival lower morbidity regimens should remain the standard therapy.

Randomized study of intensified anthracycline doses for induction and recombinant interleukin-2 for maintenance in patients with acute myeloid leukemia age 50 to 70 years: results of the ALFA-9801 study.

PubMed

Pautas, Cecile; Merabet, Fatiha; Thomas, Xavier; Raffoux, Emmanuel; Gardin, Claude; Corm, Selim; Bourhis, Jean-Henri; Reman, Oumedaly; Turlure, Pascal; Contentin, Nathalie; de Revel, Thierry; Rousselot, Philippe; Preudhomme, Claude; Bordessoule, Dominique; Fenaux, Pierre; Terré, Christine; Michallet, Mauricette; Dombret, Hervé; Chevret, Sylvie; Castaigne, Sylvie

2010-02-10

PURPOSE In patients with acute myeloid leukemia (AML), induction chemotherapy is based on standard doses of anthracyclines and cytarabine. High doses of cytarabine have been reported as being too toxic for patients older than age 50 years, but few studies have evaluated intensified doses of anthracyclines. PATIENTS AND METHODS In this randomized Acute Leukemia French Association 9801 (ALFA-9801) study, high doses of daunorubicin (DNR; 80 mg/m(2)/d x 3 days) or idarubicin (IDA4; 12 mg/m(2)/d x 4 days) were compared with standard doses of idarubicin (IDA3; 12 mg/m(2)/d x 3 days) for remission induction in patients age 50 to 70 years, with an event-free survival (EFS) end point. After two consolidation courses based on intermediate doses of cytarabine, patients in continuous remission were randomly assigned to receive or not receive maintenance therapy with recombinant interleukin-2 (rIL-2; 5 x 10(6) U/m(2) x 5 days each month) for a total duration of 12 months. A total of 468 patients entered the study (median age, 60 years). Results Overall complete remission rate was 77% with significant differences among the three randomization arms (83%, 78%, and 70% in the IDA3, IDA4, and DNR arms, respectively; P = .04). However, no significant differences were observed in relapse incidence, EFS, or overall survival among the three arms. In the 161 patients randomly assigned for maintenance therapy, no difference in outcome was observed between the rIL-2 and the no further treatment arms. CONCLUSION Neither intensification of anthracycline doses nor maintenance with rIL-2 showed a significant impact on AML course, at least as scheduled in this trial.

Combined effects of starvation and butyrate on autophagy-dependent gingival epithelial cell death.

PubMed

Evans, M; Murofushi, T; Tsuda, H; Mikami, Y; Zhao, N; Ochiai, K; Kurita-Ochiai, T; Yamamoto, M; Otsuka, K; Suzuki, N

2017-06-01

Bacteria in the dental biofilm surrounding marginal gingival grooves cause periodontal diseases. Numerous bacteria within the biofilm consume nutrients from the gingival crevicular fluid. Furthermore, some gram-negative bacteria in mature dental biofilms produce butyrate. Thus, gingival epithelial cells in close proximity to mature dental biofilms are at risk of both starvation and exposure to butyrate. In the present study, we determined the combined effects of starvation and butyrate exposure on gingival epithelial cell death and the underlying mechanisms. The Ca9-22 cell line was used as an in vitro counterpart of gingival epithelial cells. Cell death was measured as the amount of total DNA in the dead cells using SYTOX Green dye, which penetrates through membranes of dead cells and emits fluorescence when it intercalates into double-stranded DNA. AMP-activated protein kinase (AMPK) activity, the amount of autophagy, and acetylation of histone H3 were determined using western blot. Gene expression levels of microtubule-associated protein 1 light chain 3b (lc3b) were determined using quantitative reverse transcription-polymerase chain reaction. Butyrate-induced cell death occurred in a dose-dependent manner whether cells were starved or fed. However, the induction of cell death was two to four times higher when cells were placed under starvation conditions compared to when they were fed. Moreover, both starvation and butyrate exposure induced AMPK activity and autophagy. While AMPK inactivation resulted in decreased autophagy and butyrate-induced cell death under conditions of starvation, AMPK activation resulted in butyrate-induced cell death when cells were fed. Combined with the results of our previous report, which demonstrated butyrate-induced autophagy-dependent cell death, the results of this study suggest that the combination of starvation and butyrate exposure activates AMPK inducing autophagy and subsequent cell death. Notably, this combination markedly induced LC3B production and the induction was attenuated by AMPK inhibition. LC3B knockdown, in turn, significantly decreased butyrate-induced cell death. Therefore, AMPK-dependent LC3B induction apparently plays an important role in butyrate-induced cell death. There was a lack of correspondence between the levels of AMPK activation and LC3B induction; this may reflect the histone deacetylase-inhibitory capacity of butyrate on histone proteins. Taken together, starvation and butyrate exposure promote autophagy via AMPK signaling, while the histone deacetylase-inhibitory effects of butyrate alter chromatin to transcriptionally active state, resulting in strong LC3B induction and subsequent cell death. These findings may help improve the understanding of the cellular processes underlying periodontal disease initiation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Tyrosinase overexpression promotes ATM-dependent p53 phosphorylation by quercetin and sensitizes melanoma cells to dacarbazine.

PubMed

Thangasamy, Thilakavathy; Sittadjody, Sivanandane; Limesand, Kirsten H; Burd, Randy

2008-01-01

Dacarbazine (DTIC) has been used for the treatment of melanoma for decades. However, monotherapy with this chemotherapeutic agent results only in moderate response rates. To improve tumor response to DTIC current clinical trials in melanoma focus on combining a novel targeted agent with chemotherapy. Here, we demonstrate that tyrosinase which is commonly overexpressed in melanoma activates the bioflavonoid quercetin (Qct) and promotes an ataxia telangiectasia mutated (ATM)-dependent DNA damage response. This response sensitizes melanoma cells that overexpress tyrosinase to DTIC. In DB-1 melanoma cells that overexpress tyrosinase (Tyr(+) cells), the threshold for phosphorylation of ATM and p53 at serine 15 was observed at a low dose of Qct (25 microM) when compared to the mock transfected pcDNA3 cells, which required a higher dose (75 microM). Both pcDNA3 and Tyr(+) DB-1 cells demonstrated similar increases in phosphorylation of p53 at other serine sites, but in the Tyr(+) cells, DNApk expression was found to be reduced compared to control cells, indicating a shift towards an ATM-mediated response. The DB-1 control cells were resistant to DTIC, but were sensitized to apoptosis with high dose Qct, while Tyr(+) cells were sensitized to DTIC with low or high dose Qct. Qct also sensitized SK Mel 5 (p53 wildtype) and 28 (p53 mutant) cells to DTIC. However, when SK Mel 5 cells were transiently transfected with tyrosinase and treated with Qct plus DTIC, SK Mel 5 cells demonstrated a more than additive induction of apoptosis. Therefore, this study demonstrates that tyrosinase overexpression promotes an ATM-dependent p53 phosphorylation by Qct treatment and sensitizes melanoma cells to dacarbazine. In conclusion, these results suggest that Qct or Qct analogues may significantly improve DTIC response rates in tumors that express tyrosinase.

Tyrosinase Overexpression Promotes ATM-Dependent p53 Phosphorylation by Quercetin and Sensitizes Melanoma Cells to Dacarbazine

PubMed Central

Thangasamy, Thilakavathy; Sittadjody, Sivanandane; H. Limesand, Kirsten; Burd, Randy

2008-01-01

Dacarbazine (DTIC) has been used for the treatment of melanoma for decades. However, monotherapy with this chemotherapeutic agent results only in moderate response rates. To improve tumor response to DTIC current clinical trials in melanoma focus on combining a novel targeted agent with chemotherapy. Here, we demonstrate that tyrosinase which is commonly overexpressed in melanoma activates the bioflavonoid quercetin (Qct) and promotes an ataxia telangiectasia mutated (ATM)-dependent DNA damage response. This response sensitizes melanoma cells that overexpress tyrosinase to DTIC. In DB-1 melanoma cells that overexpress tyrosinase (Tyr cells), the threshold for phosphorylation of ATM and p53 at serine 15 was observed at a low dose of Qct (25 μM) when compared to the mock transfected pcDNA3 cells, which required a higher dose (75 μM). Both pcDNA3 and Tyr DB-1 cells demonstrated similar increases in phosphorylation of p53 at other serine sites, but in the Tyr cells, DNApk expression was found to be reduced compared to control cells, indicating a shift towards an ATM-mediated response. The DB-1 control cells were resistant to DTIC, but were sensitized to apoptosis with high dose Qct, while Tyr cells were sensitized to DTIC with low or high dose Qct. Qct also sensitized SK Mel 5 (p53 wildtype) and 28 (p53 mutant) cells to DTIC. However, when SK Mel 5 cells were transiently transfected with tyrosinase and treated with Qct plus DTIC, SK Mel 5 cells demonstrated a more than additive induction of apoptosis. Therefore, this study demonstrates that tyrosinase overexpression promotes an ATM-dependent p53 phosphorylation by Qct treatment and sensitizes melanoma cells to dacarbazine. In conclusion, these results suggest that Qct or Qct analogues may significantly improve DTIC response rates in tumors that express tyrosinase. PMID:18791269

[Apoptosis of multiple myeloid cells induced by polysaccharides extracts from Hedyotis diffusa and its mechanism].

PubMed

Lin, Sheng-yun; Shen, Chu-yun; Jiang, Jian-ping; Wu, Li-qiang; Dai, Tie-ying; Qian, Wen-bing; Meng, Hai-tao

2013-04-01

To explore the proliferation inhibition and apoptosis effects of polysaccharides extracts from Hedyotis diffusa (PEHD) on multiple myeloma (MM) cell line RPMI 8226 cells in vitro, so as to provide experimental theory for the clinical application in the treatment of MM. MTT assay was used to examine the effects of PEHD on cell growth. The apoptotic cells were analyzed by flow cytometry with AnnexinⅤ/PI staining. Hoechst staining was used to observe the morphological changes of RPMI 8226 cell apoptosis. The expression levels of caspase-3,-8,-9, PARP, nucleoprotein NF-κB protein and other channel protein were assayed by Western blotting method. The growth of RPMI 8226 cells were suppressed after treatment with PEHD, the highest inhibition rate reached to 92.3%, the results in the doses from 1 to 4 mg/ml showed a dose-and-time-dependent manner. The proportion of apoptotic cells in 1, 2 and 3 mg/ml PEHD treatment groups for 24 h were 22.52%, 62.31% and 69.94%, respectively, and significantly higher than that of control 8.93%. After treated with PEHD, apoptotic body appeared in RPMI 8226 cells nucleus and the number of apoptotic body increased in a dose-dependent manner. With the increasing of PEHD concentration, the expression of caspase-8,-9,-3 and PARP protein increased. The expression of Mcl-1, Bcl-xl, Bid and Bim protein decreased gradually, but the expression of Bax, Bak and Bad protein increased, and the expression of p-AKT protein (60 kDa) and NF-κB obviously decreased. PEHD could inhibited the growth of RPMI 8226 cells and displayed a dose-and-time-dependent manner, its mechanism may involve cell apoptosis induction, which was associated with the activation of caspase-8, caspase-9, and caspase-3 protein and the down-regulation of p-AKT and NF-κB protein expression.

The use of nutritional supplements to induce ketosis and reduce symptoms associated with keto-induction: a narrative review.

PubMed

Harvey, Cliff J D C; Schofield, Grant M; Williden, Micalla

2018-01-01

Adaptation to a ketogenic diet (keto-induction) can cause unpleasant symptoms, and this can reduce tolerability of the diet. Several methods have been suggested as useful for encouraging entry into nutritional ketosis (NK) and reducing symptoms of keto-induction. This paper reviews the scientific literature on the effects of these methods on time-to-NK and on symptoms during the keto-induction phase. PubMed, Science Direct, CINAHL, MEDLINE, Alt Health Watch, Food Science Source and EBSCO Psychology and Behavioural Sciences Collection electronic databases were searched online. Various purported ketogenic supplements were searched along with the terms "ketogenic diet", "ketogenic", "ketosis" and ketonaemia (/ ketonemia). Additionally, author names and reference lists were used for further search of the selected papers for related references. Evidence, from one mouse study, suggests that leucine doesn't significantly increase beta-hydroxybutyrate (BOHB) but the addition of leucine to a ketogenic diet in humans, while increasing the protein-to-fat ratio of the diet, doesn't reduce ketosis. Animal studies indicate that the short chain fatty acids acetic acid and butyric acid, increase ketone body concentrations. However, only one study has been performed in humans. This demonstrated that butyric acid is more ketogenic than either leucine or an 8-chain monoglyceride. Medium-chain triglycerides (MCTs) increase BOHB in a linear, dose-dependent manner, and promote both ketonaemia and ketogenesis. Exogenous ketones promote ketonaemia but may inhibit ketogenesis. There is a clear ketogenic effect of supplemental MCTs; however, it is unclear whether they independently improve time to NK and reduce symptoms of keto-induction. There is limited research on the potential for other supplements to improve time to NK and reduce symptoms of keto-induction. Few studies have specifically evaluated symptoms and adverse effects of a ketogenic diet during the induction phase. Those that have typically were not designed to evaluate these variables as primary outcomes, and thus, more research is required to elucidate the role that supplementation might play in encouraging ketogenesis, improve time to NK, and reduce symptoms associated with keto-induction.

The use of nutritional supplements to induce ketosis and reduce symptoms associated with keto-induction: a narrative review

PubMed Central

Schofield, Grant M.; Williden, Micalla

2018-01-01

Background Adaptation to a ketogenic diet (keto-induction) can cause unpleasant symptoms, and this can reduce tolerability of the diet. Several methods have been suggested as useful for encouraging entry into nutritional ketosis (NK) and reducing symptoms of keto-induction. This paper reviews the scientific literature on the effects of these methods on time-to-NK and on symptoms during the keto-induction phase. Methods PubMed, Science Direct, CINAHL, MEDLINE, Alt Health Watch, Food Science Source and EBSCO Psychology and Behavioural Sciences Collection electronic databases were searched online. Various purported ketogenic supplements were searched along with the terms “ketogenic diet”, “ketogenic”, “ketosis” and ketonaemia (/ ketonemia). Additionally, author names and reference lists were used for further search of the selected papers for related references. Results Evidence, from one mouse study, suggests that leucine doesn’t significantly increase beta-hydroxybutyrate (BOHB) but the addition of leucine to a ketogenic diet in humans, while increasing the protein-to-fat ratio of the diet, doesn’t reduce ketosis. Animal studies indicate that the short chain fatty acids acetic acid and butyric acid, increase ketone body concentrations. However, only one study has been performed in humans. This demonstrated that butyric acid is more ketogenic than either leucine or an 8-chain monoglyceride. Medium-chain triglycerides (MCTs) increase BOHB in a linear, dose-dependent manner, and promote both ketonaemia and ketogenesis. Exogenous ketones promote ketonaemia but may inhibit ketogenesis. Conclusions There is a clear ketogenic effect of supplemental MCTs; however, it is unclear whether they independently improve time to NK and reduce symptoms of keto-induction. There is limited research on the potential for other supplements to improve time to NK and reduce symptoms of keto-induction. Few studies have specifically evaluated symptoms and adverse effects of a ketogenic diet during the induction phase. Those that have typically were not designed to evaluate these variables as primary outcomes, and thus, more research is required to elucidate the role that supplementation might play in encouraging ketogenesis, improve time to NK, and reduce symptoms associated with keto-induction. PMID:29576959

The induction of hyperthermia in rabbit liver by means of duplex stainless steel thermoseeds.

PubMed

Park, Byeong Ho; Koo, Bong Sig; Kim, Young Kon; Kim, Moon Kon

2002-01-01

To determine the heating characteristics of needle-shaped duplex stainless steel thermoseeds, and to evaluate their effectiveness in the induction of hyperthermia in rabbit liver. Thermoseeds of the two different shapes, L-shaped for single doses of hyperthermia and I-shaped for in-vitro study and repeated hyperthermic induction, were prepared. For the in-vitro study, an I-shaped thermoseed 0.23 mm in diameter and 25 mm long was placed inside a plastic tube filled with water. Heat was applied for 30 minutes within an induction magnetic field, and during this time changes in temperature were recorded using three thermocouples. For the in-vivo study, fifteen New Zealand white rabbits were divided into five equal groups. An I-shaped or L-shaped thermoseed was inserted in each rabbit's liver, and then placed within the center of the magnetic induction coil during a 30-minute period of hyperthermia. The rabbits in the first group were sacrificed immediately after hyperthermia was induced once, while those in the other groups were sacrificed at 1, 3, and 7 days, respectively, also after one induction. The remaining three rabbits were sacrificed 4 days after three consecutive daily treatment sessions. The resected segments of liver were subsequently evaluated histopathologically for the extent of coagulation necrosis caused by heating of the thermoseed. The in-vitro study demonstrated that the temperature in the thermoseed, which was 25.9 degrees C before heating and 54.8 degrees C after heating, rose rapidly at first but progressively less rapidly as time elapsed. Light microscopic examination of the rabbits' livers revealed coagulation necrosis and infiltration by inflammatory cells around the insertion site of the thermoseed. The maximum diameter of coagulation necrosis was 2.81+/-1.68 mm, and this occurred in the rabbits that were sacrificed 7 days after heat induction. Needle-shaped duplex stainless steel thermoseeds show temperature-dependent-type heating characteristics, and in rabbit liver, induced coagulation necrosis of surrounding tissues after heat is applied for 30 minutes. These thermoseeds may thus be useful for the induction of interstitial hyperthermia.

The Induction of Hyperthermia in Rabbit Liver by means of Duplex Stainless Steel Thermoseeds

PubMed Central

Koo, Bong Sig; Kim, Young Kon; Kim, Moon Kon

2002-01-01

Objective To determine the heating characteristics of needle-shaped duplex stainless steel thermoseeds, and to evaluate their effectiveness in the induction of hyperthermia in rabbit liver. Materials and Methods Thermoseeds of the two different shapes, L-shaped for single doses of hyperthermia and I-shaped for in-vitro study and repeated hyperthermic induction, were prepared. For the in-vitro study, an I-shaped thermoseed 0.23 mm in diameter and 25 mm long was placed inside a plastic tube filled with water. Heat was applied for 30 minutes within an induction magnetic field, and during this time changes in temperature were recorded using three thermocouples. For the in-vivo study, fifteen New Zealand white rabbits were divided into five equal groups. An I-shaped or L-shaped thermoseed was inserted in each rabbit's liver, and then placed within the center of the magnetic induction coil during a 30-minute period of hyperthermia. The rabbits in the first group were sacrificed immediately after hyperthermia was induced once, while those in the other groups were sacrificed at 1, 3, and 7 days, respectively, also after one induction. The remaining three rabbits were sacrificed 4 days after three consecutive daily treatment sessions. The resected segments of liver were subsequently evaluated histopathologically for the extent of coagulation necrosis caused by heating of the thermoseed. Results The in-vitro study demonstrated that the temperature in the thermoseed, which was 25.9℃ before heating and 54.8℃ after heating, rose rapidly at first but progressively less rapidly as time elapsed. Light microscopic examination of the rabbits' livers revealed coagulation necrosis and infiltration by inflammatory cells around the insertion site of the thermoseed. The maximum diameter of coagulation necrosis was 2.81 ± 1.68 mm, and this occurred in the rabbits that were sacrificed 7 days after heat induction. Conclusion Needle-shaped duplex stainless steel thermoseeds show temperature-dependent-type heating characteristics, and in rabbit liver, induced coagulation necrosis of surrounding tissues after heat is applied for 30 minutes. These thermoseeds may thus be useful for the induction of interstitial hyperthermia. PMID:12087199

Clinical Impact of Additional Cytogenetic Aberrations, cKIT and RAS Mutations, and Treatment Elements in Pediatric t(8;21)-AML: Results From an International Retrospective Study by the International Berlin-Frankfurt-Münster Study Group

PubMed Central

Klein, Kim; Kaspers, Gertjan; Harrison, Christine J.; Beverloo, H. Berna; Reedijk, Ardine; Bongers, Mathilda; Cloos, Jacqueline; Pession, Andrea; Reinhardt, Dirk; Zimmerman, Martin; Creutzig, Ursula; Dworzak, Michael; Alonzo, Todd; Johnston, Donna; Hirsch, Betsy; Zapotocky, Michal; De Moerloose, Barbara; Fynn, Alcira; Lee, Vincent; Taga, Takashi; Tawa, Akio; Auvrignon, Anne; Zeller, Bernward; Forestier, Erik; Salgado, Carmen; Balwierz, Walentyna; Popa, Alexander; Rubnitz, Jeffrey; Raimondi, Susana; Gibson, Brenda

2015-01-01

Purpose This retrospective cohort study aimed to determine the predictive relevance of clinical characteristics, additional cytogenetic aberrations, and cKIT and RAS mutations, as well as to evaluate whether specific treatment elements were associated with outcomes in pediatric t(8;21)-positive patients with acute myeloid leukemia (AML). Patients and Methods Karyotypes of 916 pediatric patients with t(8;21)-AML were reviewed for the presence of additional cytogenetic aberrations, and 228 samples were screened for presence of cKIT and RAS mutations. Multivariable regression models were used to assess the relevance of anthracyclines, cytarabine, and etoposide during induction and overall treatment. End points were the probability of achieving complete remission, cumulative incidence of relapse (CIR), probability of event-free survival, and probability of overall survival. Results Of 838 patients included in final analyses, 92% achieved complete remission. The 5-year overall survival, event-free survival, and CIR were 74%, 58%, and 26%, respectively. cKIT mutations and RAS mutations were not significantly associated with outcome. Patients with deletions of chromosome arm 9q [del(9q); n = 104] had a lower probability of complete remission (P = .01). Gain of chromosome 4 (+4; n = 21) was associated with inferior CIR and survival (P < .01). Anthracycline doses greater than 150 mg/m2 and etoposide doses greater than 500 mg/m2 in the first induction course and high-dose cytarabine 3 g/m2 during induction were associated with better outcomes on various end points. Cumulative doses of cytarabine greater than 30 g/m2 and etoposide greater than 1,500 mg/m2 were associated with lower CIR rates and better probability of event-free survival. Conclusion Pediatric patients with t(8;21)-AML and additional del(9q) or additional +4 might not be considered at good risk. Patients with t(8;21)-AML likely benefit from protocols that have high doses of anthracyclines, etoposide, and cytarabine during induction, as well as from protocols comprising cumulative high doses of cytarabine and etoposide. PMID:26573082

A randomized 2×2 factorial trial, part 1: single-dose rabbit antithymocyte globulin induction may improve renal transplantation outcomes.

PubMed

Stevens, R Brian; Foster, Kirk W; Miles, Clifford D; Lane, James T; Kalil, Andre C; Florescu, Diana F; Sandoz, John P; Rigley, Theodore H; Nielsen, Kathleen J; Skorupa, Jill Y; Kellogg, Anna M; Malik, Tamer; Wrenshall, Lucile E

2015-01-01

We conducted a randomized and unblinded 2 × 2 sequential-factorial trial, composed of an induction arm (part 1) comparing single-dose (SD) versus divided-dose rabbit antithymocyte globulin (rATG), and a maintenance arm (part 2) comparing tacrolimus minimization versus withdrawal. We report the long-term safety and efficacy of SD-rATG induction in the context of early steroid withdrawal and tacrolimus minimization or withdrawal. Patients (n=180) received 6 mg/kg rATG, SD or four alternate-day doses (1.5 mg/kg/dose), with early steroid withdrawal and tacrolimus or sirolimus maintenance. After 6 months targeted maintenance levels were tacrolimus, 2 to 4 ng/mL and sirolimus, 4 to 6 ng/mL or, if calcineurin inhibitor-withdrawn, sirolimus 8 to 12 ng/mL with mycophenolate mofetil 2 g two times per day. Primary endpoints were renal function (abbreviated modification of diet in renal disease) and chronic graft histopathology (Banff). Secondary endpoints included patient survival, graft survival, biopsy-proven rejection, and infectious or noninfectious complications. Follow-up averaged longer than 4 years. Tacrolimus or sirolimus and mycophenolate mofetil exposure was identical between groups. The SD-rATG associated with improved renal function (2-36 months; P<0.001) in deceased donor recipients. The SD-rATG associated with quicker lymphocyte, CD4 T cell, and CD4-CD8 recovery and fewer infections. Cox multivariate hazard modeling showed divided-dose-rATG (P=0.019), deceased donor (P=0.003), serious infection (P=0.0.018), and lower lymphocyte count (P=0.001) associated with increased mortality. Patients with all four covariates showed a 27-fold increased likelihood of death (P=0.00002). Chronic graft histopathology, rejection rates, and death-censored graft survival were not significantly different between groups. The SD-rATG induction improves the 3-year renal function in recipients of deceased donor kidneys. This benefit, along with possibly improved patient survival and fewer infections suggest that how rATG is administered may impact its efficacy and safety.

Induction therapy with carboplatin/paclitaxel followed by concurrent carboplatin/paclitaxel and dose-escalating conformal radiotherapy in the treatment of locally advanced, unresectable non-small cell lung cancer: preliminary report of a phase I trial.

PubMed

Socinski, M A; Clark, J A; Halle, J; Steagall, A; Kaluzny, B; Rosenman, J G

1997-08-01

Locally advanced non-small cell lung cancer is optimally managed with chemotherapy and thoracic irradiation, although the most appropriate strategy is not yet defined. In this phase I trial, we use two 21-day cycles of induction chemotherapy with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) (225 mg/m2 over 3 hours) and carboplatin (area under the concentration-time curve = 6) followed by concurrent weekly paclitaxel (45 mg/m2/wk x 6) and carboplatin (area under the concentration-time curve = 2/wk x 6) and thoracic irradiation. Patients undergo three-dimensional treatment planning (conformal radiotherapy) to define the cancer target volume precisely. The phase I question being addressed in this study is the maximum tolerated radiation dose given concurrently with low-dose paclitaxel and carboplatin. The initial radiation dose is 60 Gy, with dose escalations to 66 Gy, 70 Gy, and 74 Gy being planned. Ten patients have been entered thus far (eight men and two women). Their median age is 67 years (range, 59 to 78 years), and none of the patients has had greater than 5% pretreatment weight loss. Seven of 10 are evaluable for response to induction carboplatin and paclitaxel, with a response rate of 57% (three partial responses and one minor response). Three patients had stable disease and none of the patients had evidence of progressive disease during induction chemotherapy. Three patients have completed all treatment at 60 Gy and one has completed all treatment at 66 Gy. Three of the four patients have had partial responses (75%), with the remaining patient having stable disease. Toxicity in the concurrent chemoradiotherapy portion of the trial thus far has consisted of grade 3 neutropenia in one patient and grade 4 lymphocytopenia in all four patients. No grade 3 or 4 nonhematologic toxicity has been seen. The trial data are not yet mature enough to report on survival. Accrual and treatment is continuing at the 66 Gy radiation dose level.

Prevention of propofol-induced pain in children: pretreatment with small doses of ketamine.

PubMed

Zhao, Guang-yi; Guo, Yao; Bao, Shu-min; Meng, Ling-xin; Zhang, Li-hong

2012-06-01

To evaluate the efficacy of ketamine in preventing propofol injection pain in children. Prospective, randomized, double-blinded, placebo-controlled study. University-affiliated hospital. 192 ASA physical status 1 and 2 pediatric patients. Patients were randomly assigned to 4 groups. Group S (control) received normal saline as a placebo; Group K1, Group K3, and Group K5 received 0.1 mg/kg, 0.3 mg/kg, and 0.5 mg/kg of ketamine, respectively. Fifteen seconds after the ketamine injection, patients were injected with propofol at a rate of 12 mL/min until loss-of-eyelash reflex. Pain was evaluated blindly at the time of induction using a 4-point scale: 0 = no pain, 1 = mild pain, 2 = moderate pain, and 3 = severe pain. Adverse effects were recorded. Characteristics of induction of anesthesia, such as dose of propofol and time from propofol injection to loss of consciousness (induction duration), were noted. 39 (84.8%) Group S (control) patients had pain. Pretreatment with ketamine reduced the frequency of pain significantly to 56.5%, 17.0%, and 14.9% in Groups K1, K3, and K5, respectively. Furthermore, the frequency of moderate and severe pain in Group K1 (21.8%), Group K3 (6.4%), and Group K5 (4.3%) was significantly (P < 0.001, respectively) reduced compared with Group S (76.1%). Moreover, the dose of propofol for induction in Group K5 was smaller than in Group S, Group K1, and Group K3 (P < 0.05). One patient in Group K5 had emergence agitation. Pretreatment with a small dose of ketamine (0.3 mg/kg) reduced the frequency and intensity of propofol injection pain without severe adverse effects. Copyright © 2012 Elsevier Inc. All rights reserved.

Systematic review with network meta-analysis: comparative efficacy and safety of budesonide and mesalazine (mesalamine) for Crohn's disease.

PubMed

Moja, L; Danese, S; Fiorino, G; Del Giovane, C; Bonovas, S

2015-06-01

Budesonide and mesalazine (mesalamine) are commonly used in the medical management of patients with mild to moderate Crohn's disease. To assess their comparative efficacy and harm using the methodology of network meta-analysis. A comprehensive search of Medline, Embase, the Cochrane Library and ClinicalTrials.gov, through October 2014, was performed to identify randomised controlled trials (RCTs) that recruited adult patients with active or quiescent Crohn's disease, and compared budesonide or mesalazine with placebo, or against each other, or different dosing strategies of one drug. Twenty-five RCTs were combined using Bayesian network meta-analysis. Budesonide 9 mg/day, or at higher doses (15 or 18 mg/day), was shown superior to placebo for induction of remission [odds ratio (OR), 2.93; 95% credible interval (CrI), 1.52-5.39, and OR, 3.28; CrI, 1.46-7.55 respectively] and ranks at the top of the hierarchy of the competing treatments. For maintenance of remission, budesonide 6 mg/day demonstrated superiority over placebo (OR, 1.69; CrI, 1.05-2.75), being also at the best ranking position among all compared treatment strategies. No other comparisons (i.e. different doses of mesalazine vs. placebo or budesonide, for induction or maintenance of remission) reached significance. The occurrence of withdrawals due to adverse events was not shown different between budesonide, mesalazine and placebo, in both the induction and maintenance phases. Budesonide, at the doses of 9 mg/day, or higher, for induction of remission in active mild or moderate Crohn's disease, and at 6 mg/day for maintenance of remission, appears to be the best treatment choice. © 2015 John Wiley & Sons Ltd.

INDUCTION OF CYTOCHROME P450 ISOFORMS IN RAT LIVER BY TWO CONAZOLES, TRIADIMEFON AND MYCLOBUTANIL

EPA Science Inventory

1. This study was undertaken to examine the inductive effects of two triazole antifungal agents, myclobutanil and triadimefon on the expression of hepatic cytochrome P450 (CYP) genes and on the activities of CYP enzymes in male Sprague-Dawley rats. Rats were dosed by gavage for 1...

Lack of photoprotection against UVB-induced erythema by immediate pigmentation induced by 382 nm radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Black, G.; Matzinger, E.; Gange, R.W.

Immediate pigment darkening (IPD) was induced on the backs of 11 human volunteers of skin types III and IV by exposing the skin to UVA radiation (382 nm). The minimum erythema dose (MED) of UVB radiation was also determined by exposing sites to graduated doses of 304 nm radiation. The order of exposure of distinct anatomic areas was as follow: UVB followed by IPD induction; IPD induction followed by UVB; IPD induction followed 3 h later by UVB; and UVB only. Erythema responses induced by UVB were graded by inspection 24 h later and the MEDs in the 4 areasmore » were compared. The induction of IPD before UVB exposure caused no significant change in the MED compared to sites receiving UVB only, or receiving UVA radiation after UVB, confirming that the IPD reaction does not protect against UVB-induced erythema. There was also no evidence of photorecovery, i.e., an increase in the MED of UVB resulting from exposure to longer wavelength, UV or visible radiation following UVB exposure.« less

ENMD-1068, a protease-activated receptor 2 antagonist, inhibits the development of endometriosis in a mouse model.

PubMed

Wang, Yifeng; Lin, Min; Weng, Huinan; Wang, Xuefeng; Yang, Li; Liu, Fenghua

2014-06-01

Protease-activated receptor 2 plays an important role in the pathogenesis of endometriosis. We studied the effect of ENMD-1068, a protease-activated receptor 2 antagonist, on the development of endometriosis in a noninvasive fluorescent mouse model. A red fluorescent protein-expressing xenograft model of human endometriosis was created in nude mice. After endometriosis induction, the mice were injected intraperitoneally with either 25 mg/kg or 50 mg/kg ENMD-1068 or with 200 μL of the vehicle control daily for 5 days. The endometriotic lesions that developed in the mice were then counted, measured, and collected. The lesions were assessed for the production of interleukin 6 and monocyte chemotactic protein-1 by enzyme-linked immunosorbent assays and evaluated for the activation of nuclear factor-κB and the expression of vascular endothelial growth factor by immunohistochemical analyses. Cell proliferation and apoptosis were assessed by immunohistochemistry for Ki-67 and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling, respectively. ENMD-1068 dose-dependently inhibited the development of endometriotic lesions (P < .05) without apparent toxicity to various organs of the treated mice. Consistently, ENMD-1068 dose-dependently inhibited the expression of interleukin 6 and nuclear factor-κB (P < .05) and cell proliferation (P < .05) in the lesions, as well as increased the percentage of apoptotic cells (P < .05). ENMD-1068 reduced the levels of monocyte chemotactic protein-1 and vascular endothelial growth factor in the lesions (P < .05), but not in a dose-dependent manner. Our study suggests that ENMD-1068 is effective in suppressing the growth of endometriosis, which might be attributed to the drug's antiangiogenic and antiinflammatory activities. Copyright © 2014 Mosby, Inc. All rights reserved.

N-acetylcysteine inhibits induction of nitric oxide synthase in 3T3-L1 adipocytes.

PubMed

Araki, Shunsuke; Dobashi, Kazushige; Kubo, Kazuyasu; Kawagoe, Rinko; Yamamoto, Yukiyo; Shirahata, Akira

2007-12-01

The present study was designed to determine whether N-acetylcysteine (NAC), a potent antioxidant, modulates nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF-alpha) in adipocytes. Stimulation by the combination of 5 microg/ml of LPS and 100 ng/ml of TNF-alpha (LT) significantly enhanced NO production in 3T3-L1 adipocytes. Preincubation of the cells with NAC (5-20 mM) for 24 h suppressed the increased NO production in a dose-dependent manner. The production of NO was decreased by 49% at the concentration of 20 mM of NAC. The decrease in NO production by NAC was accompanied by a decrease in inducible nitric oxide synthase (iNOS) protein, detected by immunoblot analysis, and iNOS mRNA, determined by real-time reverse-transcriptase coupled polymerase chain reaction analysis. Nuclear factor-kappa B (NF-kappa B) was significantly activated by LT-treatment, while the pretreatment with 20 mM of NAC prevented the activity by 42%. Pyrrolidine dithiocarbamate (PDTC), a NF-kappaB inhibitor, also inhibited the LT-mediated NO production dose-dependently. One hundred microM of PDTC inhibited the NO production by 46%. We also investigated the effect of NAC and PDTC on the production of interleukein-6 (IL-6), which is regulated transcriptionally by NF-kappa B in 3T3-L1 adipocytes. IL-6 production was markedly increased by LT stimulus, and the enhanced secretion of IL-6 was suppressed in a dose-dependent manner by pretreatment with NAC or PDTC. These results suggest that NAC regulates iNOS expression and NO production in adipocytes through the modulating activation of NF-kappa B.

Naringin ameliorates acetic acid induced colitis through modulation of endogenous oxido-nitrosative balance and DNA damage in rats

PubMed Central

Kumar, Venkatashivam Shiva; Rajmane, Anuchandra Ramchandra; Adil, Mohammad; Kandhare, Amit Dattatraya; Ghosh, Pinaki; Bodhankar, Subhash Laxman

2014-01-01

The aim of this study was to evaluate the effect of naringin on experimentally induced inflammatory bowel disease in rats. Naringin (20, 40 and 80 mg/kg) was given orally for 7 days to Wistar rats before induction of colitis by intrarectal instillation of 2 mL of 4% (v/v) acetic acid solution. The degree of colonic mucosal damage was analyzed by examining mucosal damage, ulcer area, ulcer index and stool consistency. Intrarectal administration of 4% acetic acid resulted in significant modulation of serum alkaline phosphatase, lactate dehydrogenase, superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and myeloperoxidase (MPO) content along with colonic nitric oxide (NO), xanthine oxidase (XO) level and protein carbonyl content in the colonic tissue as well as in blood. Naringin (40 and 80 mg/kg) exerted a dose dependent (P < 0.05) ameliorative effect, as it significantly increased hematological parameter as well as colonic SOD and GSH. There was a significant (P < 0.05) and dose dependant inhibition of macroscopical score, ulcer area along with colonic MDA, MPO activity by the 7 days of pretreatment of naringin (40 and 80 mg/kg). Biochemical studies revealed a significant (P < 0.05) dose dependant inhibition in serum alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) levels by pretreatment of naringin. Increased levels of colonic NO, XO, protein carbonyl content and DNA damage were also significantly decreased by naringin pretreatment. The findings of the present investigation propose that naringin has an anti-inflammatory, anti-oxidant and anti-apoptotic potential effect at colorectal sites as it modulates the production and expression of oxidative mediators such as MDA, MPO, NO and XO, thus reducing DNA damage. PMID:24683411

Unexpected T cell regulatory activity of anti-histone H1 autoantibody: Its mode of action in regulatory T cell-dependent and -independent manners

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takaoka, Yuki; Kawamoto, Seiji, E-mail: skawa@hiroshima-u.ac.jp; Katayama, Akiko

2013-02-08

Highlights: ► Anti-histone H1 autoantibody (anti-H1) acts on T cells to inhibit their activation. ► Anti-H1 suppresses T cell activation in Treg cell-dependent and -independent manners. ► Suboptimal dose of anti-H1 enhances suppressor function of Treg cells. ► High dose of anti-H1 directly inhibits T cell receptor signaling. -- Abstract: Induction of anti-nuclear antibodies against DNA or histones is a hallmark of autoimmune disorders, but their actual contribution to disease predisposition remains to be clarified. We have previously reported that autoantibodies against histone H1 work as a critical graft survival factor in a rat model of tolerogeneic liver transplantation. Heremore » we show that an immunosuppressive anti-histone H1 monoclonal antibody (anti-H1 mAb) acts directly on T cells to inhibit their activation in response to T cell receptor (TCR) ligation. Intriguingly, the T cell activation inhibitory activity of anti-H1 mAb under suboptimal dosages required regulatory T (Treg) cells, while high dose stimulation with anti-H1 mAb triggered a Treg cell-independent, direct negative regulation of T cell activation upon TCR cross-linking. In the Treg cell-dependent mode of immunosuppressive action, anti-H1 mAb did not induce the expansion of CD4{sup +}Foxp3{sup +} Treg cells, but rather potentiated their regulatory capacity. These results reveal a previously unappreciated T cell regulatory role of anti-H1 autoantibody, whose overproduction is generally thought to be pathogenic in the autoimmune settings.« less

Assessment of phosphamidon-induced apoptosis in human peripheral blood mononuclear cells: protective effects of N-acetylcysteine and curcumin.

PubMed

Ahmed, Tanzeel; Tripathi, Ashok K; Ahmed, Rafat S; Banerjee, Basu Dev

2010-01-01

The molecular mechanism for noncholinergic toxicity of phosphamidon, an extensively used organophosphate pesticide, is still not clear. The aim of the present study is to find the possible molecular mechanism of this pesticide to induce apoptosis and the role of different drugs for attenuation of such effects. Human peripheral blood mononuclear cells (PBMC) were incubated with increasing concentrations of phosphamidon (0-20 μM) for 6-24 h. The MTT assay reveals that phosphamidon induces cytotoxicity in a dose-dependent manner. Cellular glutathione (GSH) is depleted in a dose-dependent manner from 55% to 70% at concentrations between 10 and 20 μM. The percentage of cells that bind to Annexin-V, which is a representative of cells either undergoing apoptosis or necrosis during 24 h incubation, increases in a dose-dependent manner. Above 5 μM, significant necrosis of cells was observed. DNA fragmentation assay revealed that at low concentration of phosphamidon (1 μM), no appreciable change in DNA fragmentation was seen; however, distinct fragmentation was observed beyond 2.5 μM. Phosphamidon was found to cause significant depletion of GSH, which correlates well with the percentage of cells undergoing apoptosis. An increasing trend in levels of cytochrome c was observed with increasing concentration of phosphamidon, indicating that the apoptotic effect of phosphamidon is mediated through cytochrome c release. Coadministration of the antioxidants N-acetylcysteine and curcumin attenuated phosphamidon-induced apoptosis. This further supports our hypothesis that oxidative stress, as indicated by GSH depletion, results in the induction of apoptosis by release of cytochrome c. Copyright 2010 Wiley Periodicals, Inc.